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ENFOR PROJECT NO. P-360.5.5. CONTRACT NO. 07S8.KlOI7·9·1430

SERIAL OSB79.(l()()().l

CANADIAN FORESTRY SERVICEPACIFIC FOREST RESEARCH CENTRE

VICTORIA CAJ"IlADA

3

TABLE OF CONTENTS

ABSTRACT ..FOREWORD .LEITER OF TRANSMIITAL .

SUMMARY .1. INTRODUCTION .

2 OBJECTIVES AND SCOPE .

3. STUDY METHODS AND PROCEDURES3.1 Selection and Demarcation alTest Sites ...3.2lnvenloryofLoggingResidues ....3.3 Collection and Assembly of L..cqpng Residues3.4 Processing of Logging Residues3.5 Transportation and Disposal of Processed Material3.6 Laboralory Analysts of Processed Material

4. EQUIPMENT UTILIZED4.1 Inventory EqUipment .4.2 Collection and Assembly Equipmem ...4.3 Chipper Access Road Construction Equipment ...4.4 Processing Equipment ...

a. Available Equiprnem Typesb. Processing Equipment Selectionc. Processing Equipment Used at Sooke Sited. Processing EqUipment Used at Cowichan Site ., ......•.

4.5 Transportation Equipment .

5. OBSERVATIONS5. 1Inventory Results ... . ..5.2 Collection and Assembly

a. Sooke Sileb. COVJichan Silec. Re-inventory ..

5.3 Processing .a. Soake Siteb. Cowichan Sitec. Summary of Processing Efficiencyd. RecoveIY Factors

5.4 Transportationa. Sooke Siteb. Cowichan Sile ,.................................. . .

5.5 Laboratory Analyses .5.6 Energy Consumed versus EneJg,l Produced ..

6. CONCLUSIONS AND RECOMMENDATIONS6.1 Assessment of Methods Used ..

a. Inventoryb. Collection . . . . . . . . . . .c. Processing _. . .. .. .. . . . .. . .

6.2 Summary of Production Costs and Revenues . . . . .. .. . . . . . .. . .a. Costs ...... .... . ...•.........b. Revenues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _ .c. Value 01 Processed Malena! in Tenns of Ahemative Fuels . , .

6.3 Future Research and Development Requirements . . . . . . . . . .. . .a. Biomass Invenlory .. , .b.SourceAreas .. __ "" , .c. Materials Handling Systems _ .d. Processing and Product Technology . .e. Marketing Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . "", .. ,.f. Foresl Policy and Wood Residue Utilization . . . . . . . . . . .

6.4 Concep!for Commercial Application . . . . . . _..•..............

REFERENCES .

Page567

89

9

1010ISIS1919

212121212123262631

313S3S3S3636363941434444444S48

soSOSOSO515151515252525254545555

57

4

APPENDICES1. Terminology and Conversion Factors2. Logging Residue Inventory __ .3. Illustrations and Analyses of Processed Material

UST OF TABLES

585960

Table

I2345

6

7

89

10

I I

1213

14

1516

17181920212223242526272829

30

Basic Descriptive Information on Test SitesInventory Plot Interval and Grid line SpacingList of Samples Submined lor AnalysisList of Properties Analyzed ..List 01 Modifications Carried Out on the Bartle"Chipper During the ENFOR PrO)ec1Summary of Inventory Results:Quantity of Logging Residues by Diameter Class andCondition Before Collection " ", ..................••.Summary of Inventory Results:Approximate Species Distribution of Logging Residues ' .Summary of Collection Productivity and COSl .. " ,., .Summary of Inventory Results Before and After Collection "" .......•.Sooke Processing Trials· Machine Time Summary- Bartlett Splitter .Sooke Processing Trials - Machine TIme Summary- Bartlett Chipper .Sooke Processing Trials· Summary of Production and COStsCowkhan Processing Tlials· rv'.achine Time Summary- JD 450 Log Loader . .....................•.•..................COUIichan Processing Tlials - Machine Time Summary- Nicholson Chipper . . . .. . .Cowichan Processing Trials - Summary of Production and COSIEstimated Portion of Collecred Material ""tlich could beProcessed Efficiently . _ .Collection and Processing Efficiency FactorsSummary of Laboratory Analysis ResultsRelationship of Calorific Value to Condition of WoodRelationship of Calorific Value to Moisture Contenl ..Relationship of Calorific Value 10 Species . ..........•..Relationship of Calorifi<: Value fO Tree Componem ..............•....Nicholson Chipper - Approximate Chip Size Distribution .Bartlell Chipper - Approximate Chip Size Distribution. .Energy Consumed by Operational Phase .Energy Value of Material Produced ... , ... , ...Summary of Unit Values of Energy Consumed and Produced .........•.Summary of Production Costs . _ .Cost Estimates for an Operational Forest Residue Collection.Processing and Transportation SystemCost Estimates for an Operational Forest Residue Colleclion.Prebaling. Processing and Transportation SYSlem

UST OF ILLUSTRATIONS

Poge

12121921

27

32

323536

38

3839

4()

4()

42

42434646464747484848494951

56

56

Figure

123456789

10111213141516

Key Map of Test Site Locations ,Inventory P10f Location Plan - Sooke Site .Inwntory P10f Location Plan - Cowichan Site. . ............•Logging Residue Collection Plan - Sooke Site . . . . .. .. •Logging Residue Collection Plan - Cowichan Site .Operalionall.ayout of Processing Equipment. Sooke SileOperational Layoul of Processing Equipment - Cowicnan SiteJohn Deere JD 450 with Brush Blade .Bartlett Stump Splitter Mounted on a Cr<tu.:!er l..oader .Schemalk: Diagram of the Bantett Chipper . . . . . . .Modifications 10 the BanJett Chipper .John Deere JD 450C with Log Loader .......•.Schematic Diagram of the Nicholson Chipper .Loading Position of BartJe" Chipper and Chip Truck .Loading Position of Nicholson Chipper and Chip Van , .Relationship of Oeliwred Cost and Equivalent Value ofLogging Residues 10 Changes in Diesel and Fuel Oil Prices . , . . . . . . . . . . . . . . . . . . . . • . . ..•..•.

Poge

1113141617182Q

2224252829303334

53

ABSTRACTFull utilization of the forest resource has long been

the goal of resource planners, The aim of this prOjectwas to identify and test methods of reaching thisgoal.

Forest residues on two recently logged sites repre­senting a range of residue concenlration and typewere invemoried and classified. Residues were col­lected into piles and were processed using two diffe­rent types of mobile chippers. Samples of the pro­cessed material were analyzed 10 determine theirphysical and energy properties, A portion 01 thechipped material was transported to a hog fuel boilerfor burning.

Each phase of the work was monitored to de­termine productivity. cost and fuel consumption.Results show the cost per tonne for each phase of theoperation and the ratio of energy consumed to en­ergy produced.

5

RESUME

L" utilisation complete de la ressource forestiere aete depuis Jonglemps Ie but vise par les planificateursdes ressources. Ce protet visait a identifier et experi­menter des melhodes pour arteindre un tel objeCtif

Des residus forestiers sur deux stations explollees.representant une gamme de concentrations et detypes de residus Ont e"~ inventories et classifies. Lesresidus onl ete amasses en lots et traites a raide dedeux types de dechiqueteuSes mobiles. Desechantillons du materiel traile om ete analyses pouren delerminer les proprietes physiques et energeti­ques_ Vne partie des copeaux furem transponesjusqu"a une chaudiere a dechets de bois pour lesbruler.

Chaque etape des travaux etail surveillee de presafin de determiner la productivite. les coulS et laconsommation de combustible. Les resultats indi­quem Ie cOuf par tonne pour chaque etape du travailetle rappon entre I"energie consommee el renergieproduite.

6

FOREWORD

E FOR is the bilingual acronym lor the CanadianForestry Service's ENergy Irom the FORest (ENer­gie de la FORet) program of research and develop­ment aimed al securing the knowledge and technicalcomperence to facilitate. in the medium 10 long term.a greatly increased contribution from forest biomass[0 our nation's primary energy production. Thisprogram is pan of a much larger Federal Govern­ment iniliative (0 promote the development and useof renewable energy as a means of redUCing ourdependence on petroleum and other non­renewahle energy sources.

ENFOR projects are selected from among propos­als suhmined by private and public research organi­zations according 10 scientifIC and technical merit. inthe light of program obJectives and priorities. Re­gardless of proposal source. prOjeCts are carried OUIprimarily by contract. For further information on theENFOR program. contact ...

ENFOR SecretariatCanadian Forestry 5elViceDepartment of the EnvironmentOnawa. OntarioKIAOE7

or the director of the establishment issuing thereport.

This proJect originated as an unsolicited proposalsubmined by Forestal to the ENFOR Secrelariate ofthe Canadian Forestry Service in December 1978.In February 1979. the prOjeCl (P-36) was recom­mended for suppon under the ENFOR programduring the fiscal year 1979-80. The conclusions ofthis repon are the sole responsibility of the author.and may not correspond 10 the policies or views ofthe Government of Canada. its departments oragencies. Mention of brand names does not consti­tute an endorsement by lhe Government ofCanada. its depanments or agencies. in particularbUI not restricted to the Canadian Forestry Service.

Contract preparalion was camed OUI in March1979 and project work commenced in April 1979with the selection of lesl sites. equipment. and sub·contractors for the various phases of projeCt work.

Slash on test sites was invemorie<:! and assembledinto piles during May and June. Processing of theassembled material commenced in July but had tobe postponed until late AUgUSl due to an extendedperiod of high fire hazard. Processing continued dur­ing September and all field work was completed by IOctober 1979. Data compilation and analysis werecarried out dUring October and the draft report wascompleted in November 1979.

Forestal thanks Dr. Glenn Manning of Ihe PacificForest Research Centre in Victoria. B.C. for his ex­cellem cooperation and guidance in his capacity asScientific AuthOrity for the project.

Forestal also acknowledges the cooperalion ofPacific logging Company for providing a test site altheir Soake Logging Division. The assistance ex­tended by Mr. Ray Pimloll (Division Manager) andMr. Norm Barnett (Forestry Supervisor) at theSooke Logging Division is very much appreciated.The assistance and cooperation of B.C.F.S. RangerSyd Sykes and his assistant Harold Bell in grantingpermission to use a portion of the Cowichan De­monstration Forest as a test site is also gratefullyacknowledged.

In addition. Forestal acknowledges the assistanceof Mr. W. H. Trigg of Canada Customs. of Messrs. R.Leech and G. Elliol of Canada Manpov.<er and Im­migration. of Mr. R. Collard of the B. C. MotorVehicle Branch and of Mr. M. Smith of B. C. ForeslProducls. Crofton Pulp Mill. on various phases of IheproJect.

The use of trade names for various machines inthe report does not imply any recommendation orendorsement by Forestal. The manufaclurersshould be contacted directly for currentspecifications.

A number of field measurements were made inimperial units of measure. These measurementswere convened to S. I. unilS. using appropriate con­version factors. To provide a standard basis for com­parison. all measuremenls presented in Ihis reponare in S. I. units.

FORESTAL INTERNATIONAL LIMITEDFOREST RESOURCE CONSULTANTS

1550 ALBERN. STREET

Dr. G. H. NanningCanadian Forestry ServicePacific Research Centre506 West Burnside RoadVictoria, B.C.vaz IH5

CABLE: ,,"ORESTA!..

VANCOUVER. B.C .• CANAOA

V6G lA5

13 March 1980

Reference: ENFOR Project No. P-36DSS Contract No. 075B.KL017-9-1430

Forestal Project No. F941

Dear Dr. ~~nning.

Enclosed herewith is an original typescript of our final project reportentitled: Development and Testing of a Field Treatment System for Logging Residues.Twenty-four bound copies of this report are being sent to you under separate cover.We hope that you will find the work undertaken during this study and described inthis report satisfactory and in compliance with the requirements outlined in ourcontract.

Yours truly,

FORESTAL INTERNATIONAL LIMITED

I

K.~lakeneyProject Hanager

KJB/rm

Enclosure

A MEM8ER OF THE SAN OW ELL GROUP

8

SUMMARY

1. Collection and processing of logging residuesinto a more concentrated form can be accomp­lished using land clearing equipment andmobile chippers. However. low productivityand relatively high costs make the commercialapplication of the methods developed andtested on this project uneconomical at the pre­sent time.

2, The cost of assembling residues at pointsaccessi­ble to mobile chippers ranged from $6 per tonneon nat sites with light concentrations of secondgrowth residues to $9 peT tonne for heavy con­centrations of old-growth residues on moderateslopes.

3. Processing costs averaged $70 per tonne. Thisincluded the cost of a mobile chipper and acrawler loader with a splitter or log fork attach­ment to assist the chipper.

4. Funher development is required to overcomemany problems associated with processing log­ging residues. These problems are associatedwith handling small diameter residues. damageto chipper knives by rocks and other foreignmaterial. and a general under·utilization ofequipment capacity.

5. Collection and processing recovery were af­fected by the size of residue material. The por­tion of original residue recovered in the fonn ofprocessed material was substantially lower forsmall diameter material. This was particularlynoticeable in material less than 8 centimetres indiameter.

6. Of the two mobile chippers tested. the Nicholsonchipper showed the most promise. The averageproduclivity of the Nicholson unit was doublethat of the Bartlett chipper. However. the 56­centimetre maximum size limitation would limitilS use in old-growth residues. where a largeportion of the residues is concentrated in thelarger diameter pieces.

7. The Bartlett stump splitter can be used to reducelarge stumps to smaller sized pieces prior to chip·ping. The splitting action releases most of theimbedded rocks and dirt from the root systems.

8. The Bartlett chipper. although capable of handl­ing large diameter pieces. has a very limitedproductivity due to a number of design factors.The infeed system is slow and awkward. Majormodifications would be required to overcome

Ihis problem and it is doubtful whether the chip­ping and chip outfeed mechanisms could ac­commodate any substantial increase in quantityof material. The modifications carried QUt on thisproject dealt with some of the Iimitalions of thismachine. However. much more work would berequired to develop a commercial model.

9. [f the methods developed and tested on thisproject were modified to achieve full utilizationof all equipment through simultaneous collec­tion and processing of residues. a combinedcollection and processing cost of $60 per tonnecould be achieved. Further mcx:l.ifications toovercome the problems of low productivity inprocessing small diameter material could re­duce costs 10 about $45 per tonne.

10. The average heating value of processed residueswas 10 times that of fuels consumed in the col­lection and processing operations.

II. Substantial differences in heating value wereobtained from samples of processed residues ofvarying moisture content and condition. Onlyslight differences in heating value were obtainedfrom samples of different tree species and diffe­rent tree components.

12. One tonne of logging residues has a potentialheating value equivalent to about $35 worth ofoil at current prices. HOVJever. the market valueof these residues is only 3 to $5 per tonne due toa surplus supply of wood residues from sawmillsand other "rood processing plants.

13. Increases in the price of oil will likely force manyindustrial plants to convert to wood residues fortheir energy requirements. Increased consump­tion of wood residues is expected to put suppliesof hog fuel in southwestern B. C. under severepressure by the mid·l980s. This is expected tofocus anenlion of industry on the use of loggingresidues as a source of additional fuel.

14. In preparation for the anticipated increase indemand for wood reSidues. research and de­velopment should be directed toward the fol­lowing aspects of logging residue utilization:- Logging Residue Inventory- Source Areas-Materials Handling Systems- Processing and Product Technology- Marketing Procedures- Forest Policy and Wood Residue Utilization

9

1. INTRODUCTION

Recent developments in petroleum supply andprice have focussed attention on alternative energysources. Canada' s forest resources offer a vast po­tential supply of renewable fueL One of the primeobjectives of the ENFOR program of the CanadianForestry SelVice (C.F.S.) is to study the measure­ment. haJvesting and transportation of tolal forestbiomass in order to fully exploit this energy op­portunity. [n 1978. the Pacific Forest ResearchCentre commissioned a study by Paul H. Jones andAssociates to examine the potential supply andeconomic feasibility of using logging residues forgeneration of electrical energy on Vancouver Island.This study concluded thaI by utilizing a combinationof logging residues and red alder. electrical energycould be generated at a cost approaching that of coal(20 mills per kilowatt hour).

A key step in the development of a workableforest residue utilization technology is the collectionand transportation of logging residues to a conver-

sian plant. The aim of the present project was todevelop and test a practical system for collecting andprocessing logging residues on typical west coastlogging sites. Sites were chosen to reflect a range oflogging residue accumulation and topographic con­ditions. Owing to budget limitations. equipmentselected was limited to that currently available.Some modifications were carned out to adapt exist­ing equipment to operating conditions encounteredduring the field testing phase of the project.

Field testing of the equipment and methods wascarried out on Vancouver Island during the summerof 1979. Local contractors were used for most ph­ases of the work. Forestal monitored all phases of theproject in order to determine productivity and costs.Conclusions reached were based on data collectedduring the field trials and on general impressionsgained frOm observing and working with the equip­ment on a day-to-day basis.

2. OBJECTIVES AND SCOPE

The major objectives of the project were:To identify suitable equipment, and to developmethods for collecting logglng residues from forestsites. and for processing them into a more con­centrated form which could be efficiently loaded,transported. unloaded and utilized at an energyconversion plant.

- To determine. through field testing, the technicaland economic feasibility of implementing the de­rived methods on a commercial scale.

- To collect information on the composition, physicalproperties and heat value of the matelial producedin order to assess its suitability and value as anenergy source for existing energy conversionplants.

Within the above broad ob}ectives, the follOwingspecific objectives were to be met:- To develop a system capable of handling a variety

of material representing a complete range ofspecies, piece size. concentration and condition ofresidues. Test sites selected for field mals were to berepresentative of post-harvesting conditions com­monly found on B. C. coastal logglng operations.

. To determine. by inventory methods. the quantityof forest residues on the test sites before and aftercollecting the material. This inventory also was toprovide data on the species. size. source and condi­tion of the residues.

- To collect as much of the loose forest residues asphysically possible and assemble these residues atlocations which would be accessible to transport­able timber processing equipment. The materialcollected was to be as dean and free of non­organic material as possible.

- To test different types of equipment for processingthe assembled forest residues and to monitor theproductivity of the equipment over a sufficientperiod of time to be able to assess its efficiency andsuitability for handling the material assembled.

- To carry out limited tlials of transporting the mate­rial produced in order to assess loading and un­loading methods and to obtain a measure of thevolume produced over a unit of time. In conjunc­tion with the transportation mals. weigh scales wereto be used to determine weight-volume relation­ships of the material produced.

- To determine productivily and unit cOSts for eachphase or function of the \A1Ork performed.

- To delennine the ratio of energy consumed duringall phases of the work to the equivalent energyproduced in the form of processed material.

- To Cilrry out limited modifications on the selectedequipment to make it more suitable for performing

10

the required project tasks. To identify further mod­ifications which. owing to time or budget limita­tions. could not be carried out during the proje<::t

To prepare a comprehensive technical reportdocumenting the activities of the project and pre­senting the results in a form suitable forpublication.

3. STUDY METHODS AND PROCEDURES

3.1 Selection and Demarkation ofTest Sites

To ensure that a broad range of logging residuesizes. types and concentrations would be rep­resented in the field trails. 1\'.10 test sites were selected(See key map. Fig. 1). Both sites were on areas thathad been logged within the past year. The slash wasin typical untreated post-logging condition.

One site was on Pacific Logging Company landabout 20 miles north of Sooke. B. C. on the southcoast of Vancouver Island. The olher was on Crownland in the Cowichan Demonstration Forest. 8 mileswest of Duncan. B. C. on the east coost of Van­couver Island. The sites \.ViII be referred to as theSooke and Cowichan sites in this report. They wereinitially surveyed and slash concentrations and typewere compared to the U. S. Forest Service publica­tion: Photo Series for Quantifying Forest Re­sidues (Maxwell and Ward 1976).

From this comparison. it was possible to make anapproximate preliminary estimate of the quantity oflogging slash present. This estimate was used. to­gether with an estimate of processing equipmentproductivily. to determine Ihe area of each test siterequired 10 provide sufficient slash matenal for 10 10

15 days of chipping trials.

The area required for the Soake mals was only 2hectares because of heavy residue concentrations.At the Co\.Vichan test site. where residues were light.an area of 10 hectares was selected for chippingtrials. This was subsequently reduced to about 8hectares in order to exclude root rot plots understudy by the Pacific Forest Research Centre's pro­tection group. The test site boundaries weresurveyed and delineated in the field. using a staffcompass and chain. These boundaries were used asbase lines for Ihe inventory plot grid. All points werereferenced to facilitate reestablishment at a later

See Appendix I 'or bo0rllc.al names.

date.

The Socke sire logging residues were typical ofover-mature (approximate stand age 250 - 300years) Hemlock-Balsam' forests logged by highleadcable systems in coastal B. C. The slash concentra·tion was very heavy. with many large broken logs.vJindfalls. snags and uprooted stumps. A high prop­ortion of this material was rolten. The average slopeat the teSI site was 15 to 25''6. The area wasscheduled for slash burning in the fall of 1979 andfor planting in the spring of 1980.

Logging residues on the Cowichan site were typi.cal of those found follovJing wheeled skidder loggingin young (approximate stand age: 60 years) second­growth Douglas-fir' forests. TIle slash concentrationwas relatively light and composed mainly of smallsaplings. tops and branches. The sife was relativelyflat. with a few small hummocks. No slash burningwas planned due to the light concentration of slashon the area. The area was to be planted follOWingdestumping. to arrest the spread of the root rot. Abrief summary of information on Ihe location. sizeand original foresl cover of the two test sites istabulaled in Table 1.

3.2 Inventory of Logging Residues[n early May. prior to the collection and assembly

of the logging residues. an inventory was conducledusing the planar intersect method as described in theHandbook for Inventorying Downed WoodyMaterial (Brown 1974).

All downed and woody material on or near theground wilh a diameter equal to or greater than 0.6cm was tallied in size classes from 0.6 t02.5 cm. from2.6 10 7.6 em. and then in 5-centimelTe diameterclasses from 7.710 53.3 cm. according to sound and

FORESTAL ----------,-~---__c------------------------..,

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Figure 1 - Key Map of Test Site LocationsSCALE - 1380,160

12

150m197928halOha

l. u.la )400 m~ h. I.u(a) 110m3 haC. u.lb) 270 m3 ha

R, 8% Fir 87%Ceda, 12% Ceda, 1%Hemlock 45% Deciduous 12%Balsam 34%Cypress 1m

•

Total 100°{, Total 100070

250 - 300 years 50 - 70 years75 - l00cm 30·50cm

Table 1 . Basic Descriptive Infonaation on Test Sites

Sooke Cowichan

Pacific Logging Company Cowichan Demonsrration ForestSooke Logging Division Ponion T. S. A. 10508Block No. 1271 B. C. Highway No. 18Setting No. P78-3Road No. J43-A600-700m1978-1979170 ha2 h.

ElevationDate of LoggingTotal Area LoggedArea of Test SiteOriginal Stand Data

Cruise Volume

Location andIdenlification

Siand AgeAverage Diameter (dbhl

(all. U. - Intermediate Utilization Standard(bl C. U. - Close Utilization Standard,s...... Appendix I for bolankal names

Species Distribution

Table 2 - Inventory Plot Interval and GridUneSpacing

(Metres)

ronen categories. Material that was easily kickedapan or had obviously deteriorated was classified asronen if the decayed material represented more Ihan50% of Ihe piece. Land-finn roots and stumps wereexcluded from the inventory.

A unifonn sampling grid was established on eachsite and plots were localed at fixed intervals alongthe grid lines. Grid line spacing and plot interval areshown in Table 2.

A total of 50 plots were established on each site.Transectline directions were chosen randomly usingthe second hand on a watch and 5-second intervalsto indicate one of 12 30" angles between 0" and330". Figures 2 and 3 show Ihe inventory plot loca­tion plans for Ihe Sooke and COIAIichan test sites.

Site

CowichanSooke

PlotInterval

3020

Grid LineSpacing

5020

On bolh sides. transecl lines of 1.83 metres wereused to tally intersected residual material within thediameter range of 0.6 to 7.6cm. On the Sooke sile. atransect line of 9.15 metres was used to tally in­tersecled residual material larger than 7.6 cm indiameter. The Cowichan site required a longertransect line (15.25 metres) to achieve the sameprecision level because of the lighter concentrationof material larger than 7.6 cm in diameter.

At each pial. the species composition of the re­sidual material was visually estimated. From thesepial eSlimales. a weighted average species composi­tion for each lest site was calculated. This was usedto determine the appropriate specific gravity for usein the calculation of tonnes.rheclare.

Both sides were reinventoried after the residualmaterial had been collected. On the Sooke site. thesame grid and syslem of plots were used but of theoriginal 50 plots. only 34 could be used. The remain­ing 16 plots were either in uncleared swampy areasor underneath the collected material. On the Cow­ichan site, a new unifonn grid and plot system wasused and 36 plots were established. The original gridsystem could not be used since many of the originalplots fell in areas not cleared because of swampyground conditions or because of the presence ofstudy plots of the c.F.S root rot survey.

Figure 2 - Inventory Plol Location Plan - Sooke Site 6•l>c

LEGEND

Piol Center • ~7-3

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lom.!'-zom.+20m.+zom.+ZOm.+20m.+20m.+20m.+20m,+zom.--i lom.~-!,~ ;...---.;----.;.--.-;...--~--~----.;.---.;...--...;...---.;..-----.;-.--;I

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r-- FORESTAL.

3.3 Collection and Assembly ofLogging Residues

The main ob]€Ctives in collecting logging residuesfrom Ihe projeCt test sites were:• To identify and test a method and equipment for

collecting loose logging residues.. To assess the suitability. productivity and cost of the

method and equipment tested.- To quantify the amount of material that can be

practicably salvaged from recently logged-oversites.

- To assemble a representative sample of loggingresidues al a location where they could be proces­sed using portable chipping equipment.Various types of equipment were considered for

use and the opinions of a number of persons ex­perienced in land clearing were solicited. The re­Sidue material had to be moved distances of up to100 metres. No uphill movement of material wasrequired. The amount of dirt and rock collected withthe residues was to be minimized in order to preventexcessive wear to chipper knives.

The final selection was based on equipment man­oeuvrability and cost. Small crawler tractors (40·50kwl with a lOIN hourly operating cost and the abilityto operate between slumps and on moderately steepslopes were selected. It was decided that a combina­tion of brush raking and forwarding would be used.The equipment used consisted of two J.D. 450crawler tractors. one with a brush rake attachmentfor collecting and piling the material over short dis­tances. and the other with log loading forks whichwere used to carry the piled material to a roadsideassembly point.

At the Sooke site. logging residues were collected(rom distances of up to 100 metres and piled in a 200metre long windrow adjacent to the existing loggingroad. The piled material ranged in depth from 3 to 6metres and extended up to 10 metres back from theedge of the rood.

At the Cowichan site. where tOJX)gfaphy was rela·tively flat. it was decided to collect a portion of thematerial into a windrow along the existing loggingroad and to assemble the remainder in piles locatedthroughout the site. Rough access roads were thenconstructed to these piles in order that processingequipment could travel to the assembled material.By using this method. the average distance overwhich malerial had to be moved was lessened. Thishelped to reduce collection costs and 10 reduce thequantity of dirt and rock collected along with thelogging residues. Ptgures 4 and 5 shO\Al the LoggingResidue Collection plans for the I\AJO test sites.

3.4 Processing of Logging ResidueA discussion of the equipment selection proce­

dure. along with details and specifications of equip-

15

ment used during the field trials. is included in Sec­tion 4 of this report.

At the Sooke site. a combination of equipmentwas used for processing A self-loading drum chip.per was used in conjunction with a hydraulic stumpspliner to process Ihe wide range of material sizesand rypes assembled along the logging rood thattraversed the teSI site.

The stump splitter. mounted on the front of aSO-kw crawler !ractor. split large sized and ocIdshaped cull logs. stumps and roots into pieces thatcould be more easily fed inlo the chipper opening.The splining operation was also done to removeencased rocks and dirt from stumps and roots.

The chipper was positioned at points along thepile of residues. Hydraulic stabilizer jacks were low­ered into posiiton to reduce movement of the chip­per during operatioll. Material was loaded into thechipper drum infeed hopper by a hydraulic grappleloader mounted on the rear of the chipper unit. Thisgrapple loader was also used to sort and si!; materialto remove rocks and dirt prior to feeding into thechipper. To facilitate processing. a hydraulically op­erated lid was used to force malerial down onlo thechipper drum. Material was fed vertically downwardonto a rotating chipper drum with sets of knivesmounted around its surface. The knives cut thematerial into chips and shreds which passed throughthe knife opening to the centre of Ihe drum. Here. alarge auger moved the chips along to one end of thedrum where they fell onlo a conveyer system whichcallied the processed material to a truck.

Figure 6 shows Ihe operational layout of proces­sing equipment at the Sooke site.

At the Cowichan site. logging residue piles werewidely scattered throughout the test site and roughaccess roads were constructed to those piles notlocated along the main logging road. The mobilechipper {a Nicholson. 22-inch. V-drum chipper) wastowed by a truck from one residue pile to another.

Residue material from the piles was fed by a logloader (mounted on the chipper unit) onto a hori­zontal in feed conveyor belt located at one end of thechipper unit. This belt. in conjunction with infeedrollers. moved the material into Ihe V-drum chipper.Chipped material was blO\.lJll out through a ductlocaled at the opposite end of the chipper from theinfeed belt. This duct was used 10 fill chip vans duringtransponation trials.

A small crawler loader with front-mounted logforks was used to cany material to the chipper. toassisl in moving the chipper. and to dear roads andlandings.

Figure 7 shows the operational layout of proces­sing equipment at the Cowichan site. A more de­tailed description of processing equipment and

Figure 4 - Logging Residue ColleCTion Plan - Sooke Sited•"•~•c

?~

o

i.

BLEGENQ

S.... omp

Areol NOI Cleored

CollecTed Residues

Areos Cleored

SPUR J43A

•),.k )~ \ :\~G::s:~lli\ill ~~~;o~--------- ----,----

\ LANDING

'---'-'~

.-.:i;.B:B:::S::fu~:::::::::::::-- ~----- ------SCALE 1:1,250

Figure 5 - Logging Residue Collection Plan - Cowichan ;:'ll€

I

~•:<>c

c::::::J

~'MON,

III,

/;//

'/+ ....~/<J:-O//

"",,&_~

:, '/7 " ~ '>. '', V

,\ ,:/7 ~ ·ikt~ ',,~;""~o ~_?:_~I';::::~~~.~",-"."",,..,._]1%~ ,_,_,_,_,\' 'W' \'81~ iM I '--'" -.__ -"'"<2&,,"'''' .-, '" ' ' '",, ~ ",oo.•'" 'i> " , ""'" ~ ~ _./\\\ ~ I I R'

2

500. ,.... '"'' , .<O~~, , Qr::::::

Dnl

~,' Roo! RN"O! Pdl:10red ~A. , • • • Areos-"G' \ .' -: R sidues

\ ..... .. 'I II cted e.. .. ", ,. -~- --, .. . ... .....TO " :.../'-_L· ---:::-:=---r--i-- ..... __ / ChippillgAccCROFTON "'::::='::17--1---'cCE55 LOG. ,CI",,,

LOG l...... -.J A'"'--.~

Figure 6 - Operational Layout of Processing Equipmem . Sooke Site

o•"••>;

---..--- --" ---=------::.:--- --_. -~I': "'" -- ~~_

----~ ?_--- - "';'::-- r ~..,...--- -~ - .:;-:::::-...- --=--~

_-=-_n ------....::-_=_""__.:::::-_ """"'=-"'1:

---- -----RESIDUES

---- ,~

LOGGINGPILED

~---

~,-

-A~~I~~~,,"__---

DRH

CHIP TRUCK

=KNIFEGRINDER

TRUCK

SPUR J43A

PILE OfPROCESSEDMATERIAL

LANDING

methods used at both leSI sites is contained in Sec­tion 4.4 of this report. As assessment of the results ofprocessing trtals carried out at Sooke and Cowichanis included in Section 5.3.

3.5 Transportation and Disposal ofProcessed Material

To assess loading methods. produclivity andweight-volume r31ios of the processed maleria\.rransportation lrials were carried out on a limitedbasis at both sites.

Due to truck availability and traffic density on theroads of the Sooke Logging Division. transportationtrials were carried out on only 2 days at the Sookesileo During this period. a total of six loads weremeasured and transported. Loads were transportedin a self-dumping truck with an approximate capac­ity of 20 cubic metres. Processed material was trans­ported about I kilometre and dumped at a landingnear the test site. Weighing was done with portablescales to determine individual wheel loads. whichwere then summed to give the total vehicle weightThe truck was weighed before and after loading 10

determine the nel weight of processed material.

At the Cowichan site. transportation trials werecarried OUI over a 3·day period using a 5O-cubic­metre capacity chip van. A total of six loads weretransported 10 Crofton pulp mill. where they wereweighed and unloaded. TlUcks were unloaded usinga special "tipper" type dump which was installed atCrofton to unload hog fuel into an undergroundconveyor bin which feeds the hog fuel boiler.

19

At both sites. the volume of each load was meas­ured and the loading time was carefully monitored todetermine processing productivity in terms of vol­ume produced per unit time. In addition. loads wereweighed to deterrmne the weight to volume ratio ofthe material produced. Fuel consumption and cycletime were recorded during the transportation trials.

3.6 Laboratory Analysis of Proces­sed Material

Samples of the processed material were collectedduring field trials and submitted to Beak ConsultantsLimited (Beak) for analysis. Samples were selectedto represent a typical range of types of materialfound on each test site. Two to 3 kilograms of aparticular processed material type were collectedfrom the chipper outfeed and placed in plastic bagsin order to prevent moisture loss during transport tothe laboratory. Bags were labelled in the field toidentify source area and type of material. Table 3shows the types of material sampled.

The field samples were prepared for testing at thelaboratory and analyzed to detennine a variety ofphysical properties as shown in Table 4.

[n addition to the laboratory analysis of processedmaterial eanied out by Beak. a chip analysis wascarried out on t\l,lO samples of processed materialfrom the Cowichan site by the chip testing depart­ment of a.c. Forest Products' Crofton pulp mill.This analysis shows the size dislribution of the pro­cessed material. Samples of the material processed

Table 3· List of Samples Submitted for Analysis

Sample Description

Cowiehan Test Site

Source Location

Sooke Test Site

Species

CedarCedarHem &1 (a)Hem &1Hem &1Hem &1Hem &1Hem &1Ald.,Ald.,fl,fl,fl,fl,Cedar

(a l Hemlock and Balsam mixed. See AplX'ndix 1 fOT botanical names

Type

StemwoodStemwoodStemwoodStemwoodBranchwoodStemwoodSlUmp RootsStump Roots

StemwoodSlemwoodStem RootsTops & BranchesStemwoodStemwoodStemwood

Condition

Partially rottenSoundPartially rottenRottenSoundSoundRottenSound

Green - SoundAir dry - SoundSoundSoundPartially rottenRottenSound

FOIIIE.TAL

21

Table 4 - List of Properties Analyzed

Property Basis Units

Moisture Content wet(a)

""Ash Content oven dried(b) ~

0

Calorific Value wei BTU Ib

Calorific Value oven dried BTUlb

Organic Inorganic wet ratio

Description

weight of waler as a percentage of total (wet) weight of sample

weight of non-combustible ash as a percentage of ovendried weighl

net heal released in burning a knovJn quantity of the undriedsample

net heat released in burning a knoulIl quantity of the oven driedsample

a ratio of the percentage of organic material to the percentageof inorganic material based on undried sample weight

(a) "el sampk> lIlll>- OfIgInaI Cond'll()l13S coIIo?cted in lhe Field.(b) O\'en dned Silmple has~ dned to elinunale all rTIQI:5l1Jre

at the Cowichan site were burned on the movablegrate burner system of the Crofton hog fuel firedsteam boiler. The results of these analyses are pre­sented in section 5.5 of this reJX)n. A copy of Beak' slaboratory analysis reJX)n is contained in Appendix2.

4. EQUIPMENTUTILIZED

4.1 Inventory EquipmentStandard field surveying equipment was used in

carrying out the inventory phase of the proJeCt. Th­ese equipment items and their use are described inthe Handbook for Inventorying DownedWoody Material (Brown 1974).

4.2 Collection and AssemblyEquipment

A John Deere JD4SO crawler tractor with a 2­melre-wide brush collecting blade and hydraulicwinch was used to push and skid forest residues intopiles. A John Deere JD450 crawler loader with logloading forks {spaced 1.6 metres apart} andhydraulic winch was used to foward and skid mate­rial collected by the brush blade. The brush blademachine had slandard land dearing tracks \vith 2­centimetre deep growsers which provided sufficienttraction for operating on slopes encountered on Iheproject test siles. The traclor with log forks wasequipped wilh standard slreet pads (no growsers).The absence of growsers limited the effectiveness ofthis machine in negotiating the steeper slopes on theSooke site. Figure 8 shows the John Deere JD450crawler tractor with brush blade anachmenl.

4.3 Chipper Access Road Construc·tion Equipment

A Caterpillar DSK was used to construci accessroads to residue piles on Ihe Cowichan site. Thismachine was used because it happened 10 be de·stumping rOOI TOI areas on the site at the time theaccess roads were required. The reason for using thismachine was convenience rather than suitability. Asmaller crawler tractor could have been used for thiswork with equal results.

4.4 Processing Equipmenta. Available Equipment Types

Logging residue is characteristically composedof pieces of varying size. shape and condition anddoes not lend itself to efficient materials handlingmethods. [t is this variety of piece size and shapethat makes it difficult to develop one type ofequipment that will handle the complele range ofpiece types encountered

Prior to selecting processing equipment for useon this prOject. Ihe author reviewed available in­formation on a number of equipment types andmodels. Robin T. Hamilton. in his publication.SLASH . .. Equipment and Methods 'orTreatment and Utilization. has identifiedand evalualed 50 different pieces of equipmentthat have the JX)tentialto reduce forest residues toa more homogeneous particle size and arrange­ment. This equipment generally falls into the fol­lowing broad categories.

Slash Reduction Equipment

This equipment is generally designed to moveover relatively flat ground and crush. chop. cut orflail the logging residue malerial into a ground

FORISTAI. -------------------------------------

Figure 8 - John Deere JD450 with Brush Blade

SPECIFICATIONS

Overo II LengthHe ight

WeightNet Power at 2500 rpm

3.61 m.2.54m.

6455 kg.48.5kW.

mulch. There is no processed material retrievalsystem. The ultimate purpose of this equipment isto dispose of or reduce slash to a non­objectionable form. rather than to produce autilizable product that can be easily retrieved andtransported.

Transponable Timber Processors

This equipment is generally designed to pro­duce a utilizable end product and is equipped toretrieve the processed material and deposit it intoa truck or van for transportation. Processors canbe further classified according to the method usedto break down the original material.

Chippers

Most of this equipment was originally designedto produce high-quality pulp chips from sound,debarked material in the form of whole trees orlogs. Their main limitations for use in processinglogging residues is the ineffectiveness of their cut­ting knives in slash material which is mixed withdirt and rocks and their inability to handle pieceslarger than their design capacity.

Flails and Hammer Mills

This equipment uses blunt knives or flails thatbreak, tear and crush. rather than cut or chip.These machines are generally not as sensitive toknife damage as the knife chipper. This categoryof equipment requires more power to operatethan chippers.

All of the mobile flail machines available withretrieval systems have an infeed capacity which istoo small to handle the large diameter pieces ofslash.

Hammer mills designed to handle large diame­ter pieces require very powerful engines and con­sequently are too heavy. cumbersome and ex­pensive for use in a portable slash processingsystem.

Splitters

This equipment is designed to split stumps androot masses or break up large logs. Often thisequipment is required to split larger pieces ofwood waste into smaller pieces so they can be fedinto a chipper for further processing. In breakingup the roat systems of stumps. dirt and rocks areremoved. thus reducing the chance of knife dam­age during chipping.

Another source of information consulted dur­ing the equipment selection process was a com­pendium of mobile chipping equipment con­tained in the 1976 FAO publication WoodChips· Production. Handling and Trans­port. This publication provides information on44 different chippers manufactured in Europeand NoI1h America. For each chipper. the follow-

23

ing data are shown:- Manufacturer- Chipper type (drum. "v" drum. disc. etc.}- Weight- Power requirements- Maximum size of material handled- Productivity- Cost

b. Processing Equipment Selection

[n selecting equipment for use on this project.all equipment in the two publications mentionedand some prototype models for which nopublished material was available were evaluated.The evaluation was based on the followingcriteria:- Availability for use on the project.- Capability of travelling over logging roads and

working independently at remote sites.- Suitability for processing the type of material at

the two selected test sites.- Capability of producing and retrieving material

that can be easily transported and used as anenergy source.

Slash reduction equipment was not consideredsuitable because of its inability to work on roughtopography and the absence of a retrieval systemfor the processed material.

Of the transpoI1able timber processors. thechippers seemed to hold more promise than theflail and hammer mill machines. One nail typemachine. the Fling Demolisher. was well suited toprocessing logging residues. However. it was notcapable of handling a large portion of the materialon the test sites. due to a 3D-centimetre maximummaterial size capability. Discussions with the man­ufacturer indicated that the size limitation couldnot be easily overcome. Several manufacturers ofhammer mill equipment were contacted. They allindicated that a hammer mill with a capability ofhandling large material (50-75 centimetres)would require such a large horsepower motorand heavy drive train and support structure that itwould be impractical to mount on a mobilecarrier.

For the Soake site. it was obvious from theinventory data that equipment capable of han&ing large diameter (up to 90 centimetres) materialwould be required. There are very few mobilechippers capable of handling material up to 50centimetres in diameter. There is only one com­mercially available mobile chipper that can han­dle material up to 70 centimetres in diameter.

Originally it was planned to use a chipper with a50-centimetre maximum size capacity in combi­nation with a hydraulic splitter which could re­duce the oversize material to smaller pieces thatcould be handled by the chipper. Several man-

Figure 9 - Bartlett Stump Splitler Mounted on a Crawler Loader

lNO!IO:X,'k!1

,•••;•r

//

/

//'

/'/'

/'

<.<."'~t?<:l'>

<."~~":>

o

[ J~ .:;:::;

SPECIFICATIONS

INTERNATIONAL HARVESTER175A CRAWLER LOADER

BARTLETT STUMP SPLITTERMODEL F60 - C6B

Length

Width

We ightFlywheel Power at 2400 rpm

3.0 m.2.2 m.

13,900kg.82 kW.

Weight

Blade Length

Maximum Blade Opening

Hydraulic Cylinders

Cy Ii nder Clos ing Force

3068 kg.

61 em.1.52 m.

2112,273 kg.

Figure 10 ~ Schematic Diagram of the g.,rtJeu Chipper

(Not 10 SCille)

o>

"•;•,

9

,

7

(\\

7. Chipper Drum

8. Horizontal Outteed Conveyor

9. Hydraulics Systems Motor10. Hydraulic Log Grapple

II. Hydraulic Stablizer12. Auger

~

I

LEGEND

4

12

I. Generator

2. Fuel a Water Tonks

3. Air Compressor4. Chipper Drive Motor5. V- Belts6. Infeed Hopper with Hydraulic Door

DETAIL OF

CHIPPER

DRUM

ufacturers of splitting equipment were contacted.Mr. R. Bartlett. inventor and manufacturer of aunique type of stump splitter had also developeda working prototype of a top loading chippercapable of handling materiill up to 125centimetres in diameter. Since no other availableequipment could approach this capability. thedecision was made to use this chipper for theSooke tests. To assess this machine's capabilityfor processing all residue types including stumps.the stump spliner was used in conjunction withthe prototype chipper at Sooke. The chipper andstump splitter were obtained through the man­ufacturer in Vancouver. Washinglon. U.S.A.

As previously stated. the average size of mate­rial at Cowichan was considerably smaller thanthat at Sooke. Only 3''f, of the lotal quantity ofresidues at Cowichan was greater than 53centimetres. compared to 36"'0 althe Sooke site.A chipper with a 55-centimetre infeed openingwas used for the Cowichan processing tests. Amachine of this type was found to be availableIhrough a company in Seattle. Washington.USA

c. Processing Equipment Used at theSooke Site

The stump splitter used at the Sooke sile op­erates on the principle of a tree shear. Thehydraulically powered splitter device is mountedon the front of a crawler loader and consists oltwolarge cylinders thaI drive steel splitting bladesthrough any woody material. The blades can beopened to accommodate up to ISO-centimetrediameter pieces. The carriage can rotate 85 de­grees to either side of centre so that only oneapproach by the crawler loader is necessary 10

pick up and split or cut stumps. roots or largerollen logs from a pile of residues. By breaking upthe root systems of stumps. dirt and rocks areremoved. thus reducing the chance of knife dam­age during chipping.

The hydraulic grapple loader on the chipperunit extracted oversized and odd-shaped logs.stumps and root masses from the residue pilesand put them to one side of the road for splittingby the stump splitter unit. Figure 9 shows theBartlett stump splitter mounted on a crawlerloader.

The Bartlett chipper unit was positoned atpoints along the road and material was loadedfrom residue piles adjacent to the road into thechipper drum hopper by the hydraulic grappleloader mounted on the rear of the chipper unit.The chipper operates on a top loading principle.the material being fed vertically downward onto a

26

rotating chipper drum. A hydraulically operatedlid is used to force material onto the drum. Thedrum is mounted horizontally and is driven atabout 200 revolutions per minute by a 450 kwdiesel engine. There are 14 sets of knivesmounted around the surface of the drum. Theseknives cut the material inlo chips and shredswhich pass through the knife opening and enterinto the drum. Inside the drum. a large rotatingauger moves the chips along to one end of thedrum. where they fall onto a horizontal conveyor.This conveyor moves the processed materiallat­erally to an angled conveyor which carries thematerial upward to a height of about 4 metres,from where the chips drop into a truck or van.

A separate diesel motor drives the hydraulicpumps which operate the grapple log looder. con­veyor systems, in feed hopper lid and stabilizerjacks. Figure lOis a schematic diagram of theBartlett Chipper. illustrating the location of vari­ous components of this equipment.

Several modifications were carried out on theBartlett Chipper in order to adapt and improvethe original equipment. The most important ofthese modifications was the installation of anelectric generator. which served as a powersource for a number of additional modificationsdesigned to improve the chipper unit. A briefdescription of each modification and its purposeare listed in Table 5. The approximate location ofthese modifications is shown on a schematicdiagram of the Bartlett Chipper in Figure 11.

d. Processing Equipment Used atCowichan Site

At Cowichan. a John Deere JD450 crawler loaderwilh log loading forks was used in conjunctionwith a Nicholson 22-inch Complete Tree Utilizermobile chipper. The crawler loader was used toassist in feeding material to the chipper and inmoving the chipper. This was the same loaderused to forward and pile material during the col­lection phase of the project (see section 4.2 fordescription). A diagram of the John DeereJD450C with the log loader attachment is shownin Figure 12.

The Nicholson Complete Tree Utilizer (CTUlas shown in Figure 13. is designed 10 producewoodchips from whole trees. including bark.limbs and small branches. It can handle logs andtrees up to 50-55 centimetres in diameter. Theinfeed opening on the chipper is 56 centimetres.The Complete Tree Utilizer is powered bya Cum­mins VT-1710-C635 turbo-charged diesel en­gine with a perfonnance rating of 474 kw. Thisengine drives a V-drum chipper and a series of

27

Table 5 . List of Modifications Carried Out on the Bartlett Chipper During the ENFORProject

Purpose of Modification

An auxiliary electrical system was necessary to drive a variety of back­up equipment required to make the chipper more capable of opera­ting independently al remote sites. This back-up eqUipment was re­quired primarily for knife changes and maintenance.

ReqUired for cooling chipper knives during grinding: for clean-up andfor fire protection.

ReqUired for air-impacltools used during knife changes. Air was alsoused for daily cleaning of radiator screen and air filters and to removedust and wood shaVings from critical areas of the equipment.

Required to tum drum at low speed during inspections and knifechanges. Drum was preViously turned by hand during knife changesas chipper motor is turned OJf for safety reasons.

ReqUired to assist feeding long pieces of slash into chipper drum.

Fabrication of a Portable KnifeGrinding Bench.

Modifications to Chipper DrumDrive Mechanism.

Description of Modification

1. Installation of Generator andElectrical Outlets

7. Modifications to Outfeed AugerDrive Mechanism.

S. Installation of Safety Guards andInspection Plates,

2. Installation of Water Tank Pumpand Hoses.

3. Installation of Air Compressor.Tank and Hoses.

4. Installation of an Auxiliary ElectricDrum Drive Mechanism andRemote Controls.

S. Fabrication and Installation of anAngled Chute on the Side of theInfeed Hopper.

6. Installation and SubsequentAdjustment of Chip Breakers andHolders

12.

11.

To reduce the average piece size of processed material. a set of t\vochip breakers was installed at each knife. This was done to produce asize of chip which would comply with the piece size specifications ofhogfuel boiler systems and to reduce the chance of blockage of thechipper outfeed. Several adjustments were made to these chip break­ers dUring field trials in an attempt to identify their optimum position inrelation to the chipper knives.

The turning speed of the outfeed auger in relation to th€ drum speedwas altered to reduce blockages.

A metal housing was fabricated and installed to enclose the drum drivemechanism. This was done to exclude foreign material and for safetyreasons. Inspection plates were installed in this housing to enablelubrication and adjustment of key parts_ An inspection plate was alsoinstalled in the chipper drum to assist in locating the position of drumblockages.

9, Fabrication and Installation of a This guard was required to reduce spillage of chips at the overlap ofChip Spillage Prevention Guard. the horizontal and angled outfeed conveyors.

10, Installation of an Operator-Ground This system was installed to overcome the effect of engine noise andCrew Communications System. thus enable the chipper operator to communicate with the ground

crew without dismounting from the cab.

These modifications were carried out to increase chipper efficiency.Gear ratios were altered to make allowances for extra drag caused bythe addition of chip breakers and to reduce drum blockage problems.

This eqUipment was reqUired to enable on-site sharpening of knivesand chip breakers.

The majority of these modifications were identified and carried out inVancouver. Washington prior to commencement of field trials. Someminor modifications were done at the project site during the opera­tional testing of the equipment. Comments on the effectiveness of themodifications are contained in Section 5 - Observations and Results_Suggestions for further refinements are contained in Section 6Conclusions and Recommendations.

Figure 11 - Modifications 10 the Bartlett Chipper

L.H. SIDE

12

2 3

5

6,7,8

LEGEND

10

1()<:)<'lIJ.--1I

10

I. Generator I'l Electrical Outlets2. Water Tank 8 Pump

3. Air Compress

4. Electrical Drum Dri ..... e for KnifeChanges

5. Ang led Infeed Chute

6 Chip Breakers (2 per knife) aHolders

7. Outfeed Auger Modifications8. Safety Guards 8 Inspection Plates

9. Chip Spillage Prevention Guard10. Operator - Groundcrew Communication

System

II. Drum Dri ..... e Mechanism

12. Knife Grinding Equipment Bench(not shown)

I'"OR[IT"'L. ---------------------------------------------------

Figure 12 - John Deere JD450 with Log Loader

"

'., ., ., ., .. ., .

, .".,, .!; ~~---

"

SPECIFICATIONS

Overall Length

Height

Weight

Net Power at 2500 rpm

Lifti ng Capacity

4.71 m.2.43 m.8913 kg.48.5 kW2908 kg.

Figure 13 - Schematic Diagram of the Nicholson Chipper

(NOI to scale)6•"•;>c

3

~

4

5

i_6

LEGEND

PLAN VIEW

OF CHIPPER

DRUM

7

8----

-t~M

-

I. Hydraulic Log Grapple 5. Chipper Drum 8 Drive Belt Housing2. Horizontal Infeed Conveyor 6. Hydraulic Stabilizer

3. Horizontal Infeed Roller 7. Engine4. Vertical Side Roller 8. Outfeed Chute

M. MODIFICATION - Chip Deflector

hydraulic pumps which power the conveyor.horizontal crush roller. venical side rollers. chipdischarge spout. hydraulic jacks. chipper housinglift and grapple log loader. The hydraulic systemis designed to synchronize all feed works compo­nents and is controlled by engine speed. Max~

imum governed engine speed is 2100 RPM.

The infeed conveyor is equipped with a feedchain and bars which pull incoming wood towardthe chipper drum. Maximum feed speed is 30metres per minute. A horizontal crush roller andtwo venical side rollers crush and align the incom­ing wood for optimum chipping.

The ''V'' drum chipperconlains3 sets (2 knivesper set) of large main knives. each with a 30centimetre wide cutting edge. These knives aremounted around the surface of the' 'V" shapeddrum. Mounted at the outside edge of the "V"drum are three sets (2 knives per set) of smallauxiliary knives. These small knives have an 8.5­centimetre-wide cutting edge and are spacedmid~way between the main knives (see inset. Fig.t3).

Attached to the sides of the drum are four largevanes that scoop and blow the chips into a dis­charge ducl. The end of the discharge duct can beadjusted vertically and horizontally by hydrauliccylinders so that chip discharge can be aimed asrequired for loading chip vans or trailers. A chipdeflector was fabricated and installed on the dis­charge duct during the field trials. This deflectordiverted chip flow downward into the van andcould be raised or lowered to direct chips into thefronl or rear ponion of the van.

The total weight of the CTU is approximately32 tonnes, Approximate travel dimensions are: 3metres wide. 4 metres high and 11 metres long(16.5 metres. including tractor unit). When pulledby a standard (5th wheel type) tractor unit. thechipper constitutes a legal load and does not re­quire pilot cars or special pennits. Standard con­nections are provided for air brakes and clearancelights.

Fuel tank capacity is 1200 Htres. The hydraulictank contains approximately 1200 litres ofhydraulic fluid. The basic electrical system usestwo 12 volt batteries connected in a series toprovide 24 volts. The hydraulic and air valves thatcontrol the feedworks are solenoid operated.

Controls for nonnal operation are located inthe loader cab. A cab mounted tachometer allowsthe operator to adjust feeding to match enginespeed for maximum production and smooth op­eration. Loader capacity is 3000 kilograms at fullreach of about 7 metres.

31

4.5 Transportation EquipmentThe selection of transportation equipment for use

on the field trials was governed mainly by availabilityand convenience. The main aim in carrying Ollttransportation trials was to assess the loadingmechanisms of the processing equipment and toobtain some accurate information on the weight andvolume produced over a unit of time.

At the Sooke site. a self-dumping gravel truck witha 9-cubic metre load capacity was modified byerec­tion of plywood sides above the box to increase itsload capacity to 20 cubic metres. Chips were loadedby positioning the truck under the outfeed conveyorof the Bartlett Chipper. as shown in Figure 14.

At the Cowichan site. a standard chip van wasused for transporting the processed material. Thisvan had a load capacity of approximately SO cubicrnetres. The truck was loaded from the rear with thechipper discharge duct placed over the top of thevan and the chip deflector diverting the chips into thetruck box. A net was placed over the top of the van 10prevent chip spillage during loading and transporta­tion. The loading position of the Nicholson chipperand chip van is shown in Figure 15.

Sample loads were weighed at Sooke. using port­able wheel scales. and at Cowichan. using the truckscale at the Crofton Pulp Mill.

5.0 OBSERVATIONS

5.1 Inventory ResultsAt both sites. the inventory included all logging

residue material greater than 0.6 centimetres indiameter. The average quantity of logging residueon the Cowichan site was 54.96 tonnes per hectare.At the Sooke site. there were 184.69 tonnes oflogging residue per hectare. A statistical analysis ofthese inventory results showed the precision of theseestimates to be within the attainable levels of accu­racy described in Brown (1974)'. To put these re­sidue estimates in perspective. a comparison wasmade with Jones' (1979) estimates of the amount ofsound and rotten logging residues on 42 VancouverIsland sites. The average quantity of residues onthese siles ranged from a low of 40 tonnes perhectare to a high of 400 tonnes per hectare. Theaverage for all sites surveyed was 160 tonnes perhectare.

On the Cowichan site. pieces ranged in diameterfrom 0.6 to 56 cm. on the Sooke site. from 0,6 to 86

, The standard errors of the estimates for the tv..'O test site in­vemories were - I- 19.3"1, at Cowichan and - .... 18,5% at Sooke.both at the 95"'0 confidence level TIleS<? .esults are within the311llinllble limits of - .,.20"6 as described in Brov.'ll11974),

32

Table 6· Summary of Inventory Results:Quantity of Logging Residuei!li by Diameter Class and Condition(a)

(Before Collection)

Sooke Site Cowichan Site

Diameter TORnes Percent Tonnes PercentClass (em) per Hectare alTota) per Hectare 01 Tota)

0.6 - 2.5 482 2.6 5.63 10.22.6 - 7.6 2544 138 18.02 32.87.7-27.9(sound) 42.53 230 1634 29.77.7-27.9(rotten) 6.61 36 5.40 9.8

28.0 -53.3(sound) 1840 10.0 5.63 103

280 -533(fonen) 2015 10.9 2.15 3.9

53.3 +(sound) 1.3.70 7.4 0 0

53.3 +{rotten) 53.04 28.7 1. 79 33

Total 184.69 100.0 54.96 1000

(a) loggmg residue inventory cillculillions ilrc described In Appendix 2

Table 7 . Summary of Inventory Results:Approximate Specie5 Distribution of Logging Residues (a)

Sooke Site

Species

HemlockBalsamCedar

Percent

47.532.020.5

100.0

Cowichan Site

PercentSpecies

Douglas FirAlder (and other deciduous)

87.0130

1000(a) These ligures are averages arrived ill by estimilting the percentilge of species distribution by volume on each inventory plot.

FORESTAL --------------------------------------,

Figure 14 - Loading Position of Banlen Chipper and Chip Truck

FO"ESTAL ------------------------------------------,

"W~~

Ct----'''T->I;?--1

3:w>

cm. Pieces larger than 28 cm in diameter comprised57"0 of the residue weight on the Sooke site and lessthan 18°~ on the Cowichan sileo A detailedbreakdown of residue quantities and theirpercentages by diameter classes is given in Table 6.A rough tabulation of the species distribution ofresidues on both sites is shown in Table 7.

In summary. the logging residue inventoryshowed a total of approximately 55 tonnes perhectare at the Cowichan site and approximately 185tonnes per hectare at the Sooke site. The averagepiece diameter was about 50 centimetres at Sooke.whereas.at Cowichan. the average piece diameterwas about 20 centimetres.

Following collection of the logging residues intopiles. a reinventory was callied out to determine thequantity remaining on the site. The results of thisreinventory was described in Section 5.2 (cl.

5.2 Collection and Assemblya. Sooke Site

Collection of residue material from the Sookesite began in the latter part of May. The groundconditions at the time of clearing were not favor­able. due to heavy rains prior to and during dear­ing operations. The crawler loader equipmentwith the log loading forks was stuck and unavail­able for 3.4% of the total time. This lost time couldhave been avoided if the tractor had been equip­ped with growsers. The wet weather conditionsalso greatly increased the amount of soil andother inorganic material present in the collectedmaterial.

A large number of pieces were too big to han­dle with the brush blade or log forks. These pieceshad to be skidded. using the winch line and chok­ers. Approximately 20% of the total machine timeincurred was spent on skidding material to theroadside.

The total project area covered 2.02 hectares.Of this, residual matenal was collected from 1.90hectares. The uncleared area of 0.12 hectaresconsisted of inaccessible swampy areas. A total of102 machine-hours were spent in dearing the1.90 hectares for a total collection cost of $2.995.

35

The average area cleared per machine-day was0.15 hectares. The average cost was $9.10 pertonne collected at roadside.

b. Cowichan Site

The collection of logging residues began on theCowichan site in early June under very favorableweather conditions. The site was dry at start-upand no rain occurred during the collection period.These conditions resulted in good equipment av­ailability and productivity.

Dry conditions also helped to reduce theamount of dirt and other inorganic material pre­sent in the collected residues. On the Cowichansite. it was not necessary to use the winch line asthe small material could be handled by the brushblade and log forks.

The total project area covered 10.48 hectares.Of this. residue matenal was collected from 8. 1hectares. The uncleared 2.38 hectares consistedof 0.38 hectares of inaccessible swampy areasand 2.0 hectares of root rot sample plots whichwere not disturbed.

A total of 87.5 machine-hours were spentclearing the 8. 1 hectares for a total collection costof $2,225.

The average area cleared per machine-day was0.74 hectares. This varied with slope, collectiondistance and soil conditions. The average costwas $5.89 per tonne collected. Productivity andcost per collected tonne for both sites are sum­marized in Table 8.

Collection costs at the Sooke site were 50%higher than at the Cowichan site. Reasons for thisdifference were:

- Steep topography. high stumps and deep. wetsoils limited equipment mobility at Sooke. thusreducing productivity and increasing costs.

- A number of large pieces were encountered atSooke. These pieces had to be skidded to theroad side. using the tractor winch. The extratime required to set and unhook chokers and torepair broken winch Jines reduced productivity.At Sooke some additional material (mainlystumps not included in the original inventory)

Table 8 . Summary of Collection Productivity and Cost

Item

Average area cleared per machine-dayAverage quantity collected per machine-dayCost per collected tonne

Average Daily ProductionSooke Cowichan

0.15 hectare 0.74 hectare25.9 tonnes 34.5 tonnes

$9.10 $5.89

was collected inadvenenl1y with Ihe logging re~

sidue material. The time spent on this materialcould not be identified and was excluded fromthe cost calculations.

c. Rein\le.ntory

Both tesl sites were reinventoried following thecollection of logging residues to assess the degreeof recovery achieved. Total logging residueweight of all material greater than 0.6 cm indiameter remaining on the Cowichan site was8.33 tannes per hectare. The equivalent loggingresidue weight remaining on the Sooke site was11.51 tonnes per hectare. The standard errors ofthese estimates were higher than those calculatedfor the original inventory. This was due to Ihe highdiversity in amount and distribution of dO'W'Tledmaterial after clearing. An increase in samplingintensity to improve the precision of these esti­mates was nOI possible. due to the limited area ofthe test siles. Plots spacing had to be at leastdouble Ihe length of Ihe transeCI lines in order toavoid overlaps in sampling.

On the Cowichan site. the amount of materialremaining was less than at Sooke. This was be­cause the smaller stumps and relatively nat to­pography at Cowichan resulted in increasedequipment maneuverability. making it possible toretrieve more of the logging residue material.

At Sooke. the ponion of original material col­lected was higher than at CO'JJichan. Based on theoriginal inventory. 94% of Ihe material was col­lected at Sooke: compared to 85% al Cowichan.This was due to the fact that the portion of male­rial recovered was grealer in large diameter male­rial than in small malerial. This is illustrated in thesummary of inventory results shown in Table 9.

36

The quantity of malerial actually collected maybe slightly greater than indicated in Table 9. dueto the factlhat some land finn stumps and buriedmaterial not tallied in the original inventory wereinadvertently collected along with the logging re­sidues. On the other hand. some of the collectedmaterial was losl to \vood cUITers and salvageloggers during Ihe time interval between collec­tion and processing. It was not possible to de­termine the net effeCI of these additions andlosses.

On the Cowichan site. \vhere 8. I hectares werecleared. the maximum attainable volume wouldhave been 445 lonnes. The actual volume col­lected according to the reinventory was 378 ton­nes. On the Sooke sile. where 1.9 hectares werecleared. the ma:t\imum attainable volume \vouldhave been 351 tOnnes. The actual volume col­lected according to the reinventory was 329tannes.

5.3 Processing

a. Sooke SiteProcessing trials were carried out over a 12 day

period al Sooke. using the Bartlett stump splilTerand chipper. The system was able to handle themajority of piece sizes and types encountered.with the exception of small branch and top male­rial ~vhich lended to pass through the chipperdrum without being completelychipped. Ponionsof branches deposited onto the outfeed conveyorbecame tangled in the drive sprockets and chains.resulting in frequent blockage of the oUlfeedmechanism. This inability to chip small diametermalerial was one of the main limitations of theBartleu chipper.

Table 9· Summary of Inventory Results Before and After Collection

Diameter Quantity of Logging Residues by Diameter ClassClass and Cowic:han Site SookeSiteCondition Before After Quantity Before After Quantity

Collection Collection Collected Collection Collection Collected(cml (tonnes hal (tonnes hal (tonnes hal (0;,)' (lonnes hal (tonnes hal (tonnes hal (%)'

0.6·2.5(soundl 5.63 1.86 3.77 67 4.82 1.35 3.47 722.6·7.6(sound) 18.02 4.04 13.98 78 25.44 5.07 20.37 80over 7.6(sound) 21.97 135 20.62 94 74.63 4.17 70.46 94over 7.6(rotten) 9.34 1.08 8.26 88 79.80 0.92 78.88 99Total 54.96 8.33 46.63 85 184.69 11.51 173.18 94

, Percent of original malenal on the ~te before coOecrion.

Another major factor limiting the effectivenessof the chipper was the lack of a self-feedingmechanism for long material. An infeed chutewas fabricated and installed on the side of thehopper to support longer pieces during feeding.However. they frequently had to be pushed intothe drum. using the grapple loader. This occupieda large portion of the operator's time. A self­feeding mechanism would enable the grapple tospend more time sorting and preparing materialfor feeding.

The installation of chip breakers in the chipperknives resulted in substantially reduced chip size(see photographs in Appendix 3). Some adjust­ments were required to achieve the optimum pos­itioning of the chip breakers in relation to the mainchipper knives. It was found that when the chipbreaker cutting edges were mounted flush withthe knife edges. material would not feed readilyinto the chipper drum. This situation was im­proved by recessing the chip breakers about acentimetre lower than the chipper knives so thatthe chipper knife made contact with the woodprior to the chip breaker. The knife then tended topull the material into the drum. resulting in a fasterfeed rate.

The outfeed conveyor system performedreasonably well. although its position at the sideof the chipper required an extra wide road width(9 metres) for loading a truck. A chip spillageproblem on the outfeed system was overcome byinstalling a flap at the intersection of the 1\'10

conveyors.

A number of rocks were accidentally fed intothe chipper. causing excessive knife wear. Thisproblem was reduced by making more use of thestump splitter and by using the chipper' s logloader to shake and drop the material prior tofeeding it into the chipper.

Productivity dropped substantially when thechipper knives became dull. Dull knives oftenresulted in long fibrous chips. which tended tofoul the drum. auger and conveyor works. Bestresults were obtained by changing the chipperknives daily. Attempts to resharpen the kniveswhile on the drum. using a portable disc grinder.proved ineffective. Excessive heat generated bythis type of sharpening actually resulted in in­creased knife wear. due to loss of temper.

The addition of an electric generator. air com­pressor and water system proved very useful inspeeding up the knife changing operation. Theelectric drum drive enabled the knife changingcrew to position the drum quickly and accurately.Dull knives were replaced. using air impact tools.The knife grinding bench was used for on-sitesharpening of knives and chip breakers. During

37

grinding operations. knives were cooled with afine water spray to prevent over-heating. Thewater system also proved useful for fire protectionduring cutting and welding operations and duringperiods of high fire hazard

The stump splitter proved a useful tool for re­ducing stumps to small sized pieces and for re­moving dirt and rock entrapped in the rootsystems. However. it was not as effective as anti­cipated in cutting long bole sections into smallerlengths. This was mainly due to the fact that theguides were so worn that the sphlter blades didnot mesh correctly. Stumps and rotten windfallswere cut with little problem but sound stem sec­tions were difficult to cut with the stump splitter.Eventually a chainsaw was used to cut long stemsinto shorter lengths.

Originally it was planned to exchange thestump splitter attachment periodically for a brushgrapple attachment for carrying material to thechipper. However. this was not done becausethere was sufficient material within the reach ofthe chipper unit's grapple loader to keep the chip­per supplied. From time to time the splitler unitwas used to extract large material from the pilesand simultaneously split and cany this material tothe chipper.

The stump splitter could split material muchfaster than it could be processed by the chipper.As a result. the stump splitter unit was vastlyunderutilized. It was only productive 21 % of thetotal time spent on processing trials.

Many mechanical problems were experiencedwith the Bartlett chipper. some of which were dueto a general lack of planning and organization onthe part of the operating crew. Others were due tothe experimental nature of the equipment. Thechipper was non-productive during almost half ofthe elapsed time. because of maintenance andrepairs. The majority of this non-productive timewas spent in rectifying a variety of problems in thehydraulic. electrical and drive train systems.

A complete brea kdown of stump splitter andchipper machine time utilization is shown inTables Wand 11.

During the field trials. the quantity of processedmaterial produced was measured. In 12 days offield trials. a total of 102 tonnes of processedmaterial were produced. Total production wasrelated 10 the productive machine time shown inTable 11. Average production per productivemachine hour was 3.2 tonnes. Average daily pro­duction was 8.5 tonnes. If part days are excluded,including the first and last day when setup anddemobilization were involved. the average dailyproduction would be 10.76 tonnes. This rangedfrom a low of 4 tonnes per day to a high of 19

38

Table 10 . Sooke Processing TrialsMachine Time Summarv (a)

Bartlett Splitter

SuhlOlalTotal

(itl Based on approxtm,)tdl,;~ hool'$ sperll on the pro}li'Cl SIli'OIJer il 12-day period.lb. Wamng lor allOtheT pM>olof lhi' operaoonleI 1'l1I'"I<i! nol requITed

Time ElementClassification

Productive Time

Subtotal

Non-productiveTime ­Mechanical

Subtotal

Non-productiveTime·Non-mechanical

Function

SplittingForwardingSplitting FOlWarding(simultaneous)SortingRoad and Landing Maintenance

Service and Warm-upRepairsOther

ConsultationPersonalLunch CoffeeWailing (Enging Runningl(b)Idle (e)Travel

Percent ofTime ElementClassificilt10n

17.847.2

15.00.4

19.6100 (17 hours)

73.915.510.6

100 (3 hours)

1.50.17.2

15.873.42.0

tOO (62 hours)

Percent ofTotal

Elapsed Time

3.79.7

3.10.14.1

20.7

24050.43.3

1.10.155

12.055.8

1.576.0

100 (82 hours)

Table 11 . Sooke Processing TrialsMachine Time Summary (a)

Bartlett Chipper

Percent of Percent ofTime Element Time Element TotalClassification Function Classification Elapsed Time

Productive Time Chipping 93.0 34.8Sorting 0.6 03Other 6.4 2.4

Sublolal 100 (32 hours) 37.5Non-productive Service and Wann-up 24.3 ILlTime- Repairs 42.5 19.3Mechanical Jams (drum or conveyor) 9.7 4.4

Knife Changes (b) 23.5 10.7SublOlal 100 (39 hours) 45.5

Non-productive Consultation 4.3 0.8Time- Personal 2.4 0.4Non-mechanical Lunch Coffee 31.3 5.3

Waiting 16.6 2.8Travel and Setup 40.7 6.9Miscellaneous 4.7 0.8

Subtotal 100 (15 hours) 17.0Total 100 (86 hours)

(a) Based on ilpprO)(lffi1l1ely 86 hours spent on the prol'!Ct Sill.' over a 12·day period.lb) Includes sharpening kmves in place on drum.

tonnes per day.

Average unit costs for the processing operationwere calculated. using the actual contract rate(per operating hour) and the number of operatinghours incurred. Operating hours include produc­tive machine time plus a portion of the non­produclive machine time. Repairs. maintenance.knife changes and personal breaks are not inc­luded in operaling time_ A summary of cost andproduction for the Sooke processing operalion isshown in Table 12.

The above table indicates a unit processing costof $70.10 per tonne. These costs do not includethe cost of modifications to equipment. transpor­tation of equipment to and from the pro;ecc site.and accommodalion provided for the operatorsand crew. The contractor's hourly rate did notinclude fuel. This item was provided at extra costand is shown as a separate item in the table.

The aforementioned costs are based onoperating hours only. The very high non­produclive time associated with the Sooke pro­cessing trials is not reflected in these costs. If theequipment has been leased or rented on a full·lime basis and labor hired to operate this equip'ment. the unit costs of processing would havebeen much higher.

b. Cowichan Site

Processing trials at the Cowichan Site werecarried out over a period 0113 days. Material wasprocessed using a Nicholson (22-inch) mobilechipper. A small crawler loader (J.D. 450) as­sisted the chipper by forwarding material whichwas outside the reach capacity of the chipper' slogloader. The crawler loader operator acted asground man for the chipper. carrying out suchfunctions as:- CUlling off roots and oversized stems with a

chainsaw• assisting during knife changes

39

- freeing Jammed material in the infeed and out­feed works

• assisting during chipper moves.

Additional equipment used during the proces­sing trial included a crawler tractor to build accessroads to residue piles located away from the exist­ing logging road and a 50-cubic·metre chip van tohaul processed material during transponationtrials. The system operated very well. particularlyconsidering that the operating crew had no previ­ous experience in this type of work.

The crawler loader proved very useful for car­rying material to Ihe chipper. This subslantiallyreduced the number of chipper moves required.The crawler loader also assisted during chippermoves on rough terrain and kept the roads andlandings around the chipper free of debris.

The icholson Chipper perfonned well. wilhvinually no mechanical breakdowns except forbroken hydraulic lines on the grapple loader. Thesystem was able to handle the majOrity of piecesizes and types encountered. Several large. over­sized pieces were split. using the log loader forksof the J. D. 450. Root systems were bucked offwith a chain saw. This was done to eliminate rockswhich were often imbedded in the roots. Looserocks. mixed in with the piled material. were re­moved by lifting and shaking the material with theJ.D. 450 and then lifting and dropping with thehydraulic grapple prior to feeding onto the chip­per infeed conveyor. In spite of these precautions.the occasional rock did gel into the conveyor.When this happened. the operator reversed theconveyor to reject the rock from the system. Sev­eral small rocks and one choker went through thechipper during the trials. causing excessive dam­age to the chipper knives. However. it was possi­ble to resharpen the knives and continue to usethem. One knife was broken and could not bereused.

Table 12· Sooke Processing Trials:Summary of Production and Costs

Hourly Operating Cost Production Unit Cost Portion ofItem Rate Hours Incurred (Tonnes) (Srronnes) Total ('Yo)

Bartle" Spli"erwith Operator $ 50 42 $2. 100 102 $20.59 29.4

Bartle"Chipper wilhOperator andGround Crew $100 46 $4.600 102 545.10 64.3

Cost of Fuel $ 450 $ 4.41 6.3

Total $7.150 $70.10 100.0

40

Table 13· Cowichan ProcessinaTrialsMachine TIme Summarv(a)

J.D. 450 Log Loader

Percent ofTime Element Time ElementClassification Function Classification

Productive Time Fowarding 70.7Sorting 3.1Reject Material Removal 4.4Road and Landing Maintenance 15.3Assisting Chipper Move 5.9Splitting Oversized Logs 0.6

Subtotal 100 (33 hrs.l

Non-productive Service and Warm-up 30.6Time- Repairs 68.9Mechanical Other 0.5

Subtotal 100 (4hrs.)

Non-productive Consultation 1.0Time· Personal 0.1Non-mechanical Lunch Coffee 18.7

Travel 23Waiting(b) 15.8ldle(c) 62.1

Sublotal 100 (70 hrs.)

TOlal

(al Ba5ed on apprO:<lIlliU~107 hours spent on rhe proJeCt SIte over a 13.ddy period(b) Walhng lor iUlOlne,.phaoeof 1m:- operaoon(o::} t-t.xhll1e 001 requIred. opefilllX"'orkmg M groundman.

Yable 14 . CowichaD ProcessinaTrialsMachine Time Sum.milry(iI)

Nicholson Chipper

Percent ofTotal

Elapsed Time

22.00.91.44.71.80.2

31.0

1.02.30.03.3

0.70.0

12.31.5

10.440.865.7

lDO (107 hrs.)

Percent of Percent ofTime Element Time Element TotalClassification Function Classification Elapsed Time

Productive Time Chipping 26.9 12.0Sorting and Feeding 73.1 32.6

Sublotal 100 148 h'S. J 44.6

on-productive Service and Wann-up 21.7 49Time - Repairs 18.3 4.1Mechanical Jams 30.2 6.7

Knife Change 29.8 6.7Sublotal 100 (24 hrs.) 22.4

Non-productive Consultation 12.8 4.2Time - Personal 0.8 0.3Non-mechanical Lunch/Coffee 31.3 10.3

Waiting 19.8 6.6Travel 28.9 9.5Setup 4.2 1.4Knife Inspections 2.2 0.7

Sublotal 100 (36 hrs.) 33.0Total 100 (lOB h'S. J

lal Based on apprOXllTlately 108 hours spmt on the proji.'Ct 5Iteover a 13-day penod.

As with the Bartlen Chipper. small branchesand tops \IJere difficult to process. A steady feed­ing of small pieces generally resulled in a blockedinfeed roll. due to broken pieces )amming bel­ween the roll and the chipper drum. The infeedrolls rejected a considerable amount of this shan.broken material. which collected in piles at theside of the machine. The infeed roll blockageproblem was eventually overcome by alternatingthe type of material being fed onto the infeedconveyor. From lime to time. large pieces (wind­falls or large saplings) were fed in to clear out thesmall chunks which tended to collect in the spacebetween the infeed roll and the chipper drum.

During the field trials. the operator found thatwhen engine speed dropped below 1500 RPM.there was insufficient blO\.ving pov.'er to canychips up through the discharge spout_ This oftenoccurred when chipping large \vindfalls and whenchipper knives were excessively dull. The result ofthis loss of blowing power was a blockage of chipsin the discharge duct when the operator con­tinued to feed material into The chipper. IT wasfound that by stopping the infeed works and al­lowing engine RPM to recover. the blockageproblem could be avoided. A blocked outfeedduct required from 1 to 2 hours to clear.

Due to the fact that the crawler loader was notrequired full-time and the operator worked pan ofthe time as a groundman. the loader was engagedonly in productive functions about one-third ofthe time. The remainder of the time it was idle orwaiting while the operator perfonned otherduties.

The Nicholson Chipper was productively en­gaged for about half the available time on theproject. The remainder of the time was spent on avariety of maintenance and repair items and mov­ing between logging residue piles. Only 4% of thetotal time was spent on repairing mechanicalbreakdowns. Knife maintenance and clearing ofjammed infeed or outfeed works each accountedfor about 7'''0 of the total time. A completebreakdown of chipper and crawler loader timeutilization is shown in Tables 13and 14.

The machine time summary for the Nicholsonchipper shows that it ~vas productive lor abouthalf the total elapsed time on the project. Only27"6 of this productive time was spent on chip­ping. This percentage was derived by measuringand recording the total time during which chipswere actually flowing from the OUlfeed ducl. Theremainder of the productive time was composedof soning. loading and feeding functions.

Attempts were made to measure quantities ofprocessed material produced in relation 10 chip­ping time. The Nicholson chipper outfeed blower

41

spread the processed material over a wide area.making accurate measurement of the quantityproduced very difficult.. Chip piles were measuredon selected sites where topography resulted in amore concenlrated accumulation of chips. In ad·dition to these measurements. an accuraTe mea­sure of quantities proouced were obtained duringthe loading of six chip vans over a 3-day period. Acalculation of quamities produced over unit time.using both pile measurements and chip van mea­surements. indicates an average production of76.5 cubic metres per chipping hour'. Chip vanswere weighed to determine Ihe average density ofthis processed material. The average density.based on weighing vans al Crohon. was 228.3kilograms per cubic metre (14"(, greater than thedensity of material processed by the Bartlen chip­per. mainly due to compaction caused by theblower). Based on this density. the average pro­ductivity was 17.5 tonnes per chipping hour' (4.7lennes per proouctive machine hour).

The tolal quantity processed during the 13days of field trials was 994.5 cubic metres of 227Tonnes. Average daily production was about 17.5tonnes. ranging from a low of 12 tonnes per dayto a high of 26 tonnes per day.

Average unit costs for Ihe processing opera­tions were calculated by using the rental rates forthe equipment used and the actual operatingcosts incurred for labor. fuel and other items. Asummary of cost and proouction for the Cow­!chan processing operation is shown in Table 15.

Table 15 indicates a total collection and proces­sing cost of about .~ 70 per tonne. Costs of modifi·cations to equipment. transportation of equip­ment to and from the project site and costs as­sociated with selling up the project are not inc­luded in these COSTs.

c. Summary of Processing Efficiency

Following processing trials. unprocessed mate­Iial remaining in chipper landings was examinedto determine the type and quantity of this mate­rial. The material remaining was composed of:

At Sooke site - Small diameter branchesand tops- Short broken pieces 01 alldiameters

At Cowichan site - Small diameter branches andlOp'

- Short broken pieces of alldiameters- Large and misshapen piecesover 55 em in diameter

I ChLpping hoor ~fer.; to lIw orne function· Chjpping" in lheMachIne TIfTIe Summary

42

Table 15· Cowichan Processing Trials:Summary of Production and Cost

Daily Operating eost Production Uniteo.t Portion ofItem. Rate Days (neDlTed (ToRnes) (Srronne) Total ('rot)

Chipping

Nicholson Chipper$530(0)Remal 13 $ 6.890

Operator 125 13 1.625Knife Maintenance 710Fuel and Lubricants 709Maintenance and Repairs 243

Subtotal $10.177 227(0) $44.83 64

Kenworth Truck (for moving chipper)Rental $60 13 $ 780 227 3.44 5

Other EquipmentChain Saw $ 25 13 325Pick-up/fuel tank $ 25 13 325

Subtotal $ 650 227 2.86 4Subtotal - Chipping $11.607 227 $51.13 73

Forwarding

J.D. 450 LoaderRental $200 13 $ 2.600Operator(b) 80 13 1.040

Sub!otal - Forwarding $ 3.640 227 $16.04 23

Access ROilds

Cat D8 TractorRenlal $600 $ 600 227 $ 2.64 4

Total $15.847 227 $69.81 100

(a) 8.lsed on monthly lease rilte of $9.920 (U.S.) (511.656 Can. I and a stand<!rd 22-day working month.

(bl Loader <>peTillor worked aboul4O% of his rime as groundman for chIpper.

(e) Of Ihe 227 lonnes produced. only2lOtonneswere processed from maleTi<dcoilecled during tne project The remaining 17tonneswereprocessed from material that had been collected during logging operations and left in landings.

Table 16· Estimated Portion of Collected MaterialThat Could be Processed Efficiendy

Diameter Clilss(centimetres)

0.6 - 2.52.6 - 7.67.7-27.9

28.0 - 53.353.3 +

Weighted Average fa)

Portion of Collected Material ProcessedSooke Site Cowicban Site

'l:. 'l:.

20 2070 7080 8090 9095 5085 70

(a) Weighted by quantity of residue material in each diameter class

43

Table 17 . Collection and Processing Efficiency Factors

Diameter- Sooke Site Cowichan SiteClass Collection Processing Combined Collection Processing Combined

Efficiency Efficiency Recovery Efficiency Efficiency Recovery(em) Factor Factor Factor Factor Factor Factor

0.6- 25 0.72 020 0.14 0.67 0.20 0.1326- 76 0.80 070 0.56 0.78 0.70 0557.7 -279 0.97 080 0.78 0.91 080 073

280 - 53.3 0.97 0.90 0.87 0.91 0.90 0.82533 + 0.97 0.95 0.92 0.91 0.50 046

Weighted Average 0.94 085 0.80 0.85 0.70 060

- Stumps and root systems con­taining imbedded rocks

As with the collection phase. the portion of theavailable material that could nOl be handled in­creased as the piece size decreased. [n general.the Bartlett chipper was more capable of handlingshort pieces than the Nicholson chipper. Neithermachine could efficiently handle large quantitiesof branch materiaL Many branches simply wentthrough the chipper and came out in their originalform. Estimates of the ponion of material thatcould be handled efficiently by the processingsystems. are presented in Table 16. These esti­mates are based on observations made duringprocessing trials and on examination of unproces­sed residues.

The remainder of the collected material couldnot be processed effiCiently. due to the inability ofthe system to handle certain types of material.The extra feeding time and non-productive time.due to blockages incurred in processing this mate­rial. were out of proportion to the amount ofmaterial produced. Although the Nicholson chip­per used at the Cowichan site could not handlematerial greater than 55 centimetres. a portion ofthis material (50%) could be processed by beingsplit into small pieces using the crawler loaderforks. and fed into the chipper.

d. Recovery Factors

A combined recovery factor was developed torelate the original quantity of logging residues onthe test sites to the quantity of processed materialthat could be expected to be recovered. The basicequation used is shown below.

As the collection and processing efficiencyfactors varied with the size of material. this equa­tion would be applied separately to the quantityof material in each diameter class.

Table 17 lists factors for predicting the quantityof processed material that could be producedfrom a known quantity of logging residues. Thesefactors were combined to give a weighted aver­age recovery factor based on the quantities ofmaterial measured during the trials at Sooke andCowichan.

In cleanly logged typical second growthDouglas-fir stands on flat sites. one can expect 10salvage and process about 60% of the totalamount of loose forest residues. using themethods described in this repon. In decadentold-growth Hemlock. Balsam and Cedar standson moderate slopes, one can expect 10 salvageand process about 80% of the total amount ofloose forest residues using the methods describedin this repon.

To check these factors againSI actual operatingexperience. a rationalization of source materialversus processed material for the Cowichan pro­cessing trials was made. using the factors in Table17.

Example of Combined Recovery Factor ap­plied to the Cowichan Site:

Forest residue loading according toinventory (Before Collection) 55tonnes/ha

Area from which residues were collected 8.1 ha

ProcessedMaterial

(tonnes)

Logging Residuesas Inventoried x

(tonnes)

CollectionEfficiency x

Factor

ProcessingEfficiency

Factor

44

Deductions for residues not processed I 1.0 ha

Net area from which processed residueswere collecfed 7. 1ha

Total material available for collection andprocessing 390 tonnes

estimated Processed Material recoveryaccording to Factors in Table 17 234tonnes

Actual Processed material produced frommateria! collected 210 tonnes

Difference (Estimated minus Actual) 24 tonnes

Using the conversion factors from Table 17 topredict the quantity o{ processed residues thatwould be obtained from the Cowichan site re­sulted in a 24 tonne {1O'''''o) overestimate whencompared to the quantity of processed materialactually produced from collected material. Thiserror in estimate is primarily due to collected re­sidues that were cut from the piles by fuel woodcullers over the time period between collectionand processing. An additional source of errorcould be in the processing efficiency factors.which ~vere based on estimates rather thanmeasurements.

A rationalization of the quantity of processedmaterial in relation to the quantity of logging re­sidues collected was not possible at the Sookesite. This was due to the fact that only a smallportion of the total material collected was actuallyprocessed. It was not possible to relate the re­sidues processed to the area from which theywere collected.

5.4 Transportationa. Sooke Site

During the transportation trials carried out atSooke. the angled conveyor outfeed system ofthe Bartlett chipper was used to load trucksparked alongside the chipper. A road width ofabout 9 metres was required. This limited the useof the truck-loading system to landings and roadjunctions where sufficient road width wasavailable.

The outfeed end of the conveyor can be raisedto a maximum height of about 4 metres. Toachieve an even load distribution during the fillingoperation. the end of the conveyor should beplaced over the mid·point of the van. This limitsthe system to loading trucks with a maximum sideheight of about 3.5 metres.

During 2 days of transportation trials. six loads

I Includes residue pil.ts burned in an accidental fire thatoccurred durill9 the processing trials_

of processed material were transported over adistance of 1 kilometre to a dumping point. usinga modified gravel truck. By the addition ofplywood sides extending above the standard 9­cubic-metre box. the load capacity was increasedto about 20 cubic metres. The average load car­ried during the transport trials was 18.5 cubicmetres. Weights taken during the transport trialsindicated an average payload of 3.7 tonnes. Theaverage density of the processed material wascalculated to be 200 kilograms per cubic metre.

As the transportation distance was very short (1km) and the truck was not designed for haulinglogging residue material. costs incurred during theSooke transportation trials were not representa­tive of costs under operational conditions.

Some difficulty was experienced in dumpingthe processed materiaL This was due to the"stringy" nature of the chipped material. whichtended to cling together and resist the tendency toslide easily from the truck box. However. it waspossible to dump the loads by using themomentum of the truck travelling in reverse com­bined with a sudden application of the brakes.

b. Cowichan Site

During the 3 days of transportation trials atCowichan. a total of six chip van loads of proces­sed material were transported to Crofton PulpMilL The average round trip time per load was 3.6hours. of which 2.3 hours was loading time and0.8 hours was round trip travel time for the 24kilometre distance between the processing siteand the mill. The remainder of the time was di­vided between positioning the van under thechipper and dumping and weighing at Crofton.

Vans loaded during the transportation trials av­eraged a net payload weight of 8.9 tonnes. A totalof 53 tonnes of chips were transported during the3-day period.

Chip vans were loaded by positioning the vanbehind the chipper and placing the outfeed ductover the back of the van. The force of the blowerresulted in an initial concentration of chips towardthe front of the van. followed by a spillage of chipswhen the front portion of the van was full. At­tempts were made to overcome this problem byplacing a net over the top of the van to preventspillage and by attaching a deflector to the end ofthe outfeed duct to deflect chips into the centreand rear of the van. These measures were onlypartially successful. Spillage was reduced to anacceptable level but the van continued to be une­venly loaded. resulting in under-utilization of theavailable capacity. The van. which had a nominalcapacity of 50 cubic metres. could only be filled toabout 80% of capacity due to uneven load dis-

45

trihution. Because the van was rented on a short­term basis. it was not possible 10 carry out anymajor modifications. However. it appeared thatan opening cut in the back of the van to accom­modate the chipper outfeed duct would havebeen useful. A closed topped van with an openingacross the top of the rear door for the chip outfeedduct tlJould have been the ideal vehicle for usewith the Nicholson chipper.

The in-line loading system of the Nicholsonchipper enables loading to be carried out on virtu­ally any road with a width of 3 to 4 metres. If thetruck which pulls the chipper is to be left under thechipper's fifth-wheel during loading. it must be"cocked" to an angle to permit the van to backunder the outfeed ducl. This requires an addi­tional road width of 2 to 3 metres. An alternativeto "cocking" the truck would be to use a detach­able outfeed duct extension to blow chips overthe chipper-truck and into the van. A3-to-5 metrelong extension would be required. depending onthe type of truck being used. According to themanufacturer. there would be sufficient blowerforce to prevent blockages in this extension duet.However. this was not attempted during the fieldtrials. Experience gained during the trials indi­cates that the extension duct should be horizontalor downward sloping to minimize the possiblity ofblockages.

During the field trials. the chipper either blewchips onto the site or remained idle during thetime when the van was travelling to and fromCrofton. Obviously this would not be practicalunder operational conditions. where the objec­tive would be to operate continuously and re­cover all of the processed material. [n this case. asecond van or trailer would be required to comp­lete the system. One unit would be travellingwhile the other was being loaded. resulting inmaximum utilization of all equipment.

Processed material was unloaded on the hogfuel dump at the Croft Pulp Mill. Some difficultywas experienced in dumping. The dump had tobe raised and lowered several times before thematerial finally slid out through the hinged backdoor. This difficulty was due to compaction of theprocessed material by the blower outfeed systemof the Nicholson chipper.

5.5 Laboratory AnalysesAs previously mentioned. representative samples

of the processed material were analyzed to de­termine their physical and energy properties. Theoriginal Report of Analysis from Beak Con­sultants Limited is presented in Appendix 3. A sum­mary of the results is shown in Table 18.

Moisture content of the material analyzed fromthe Sooke site was higher than that of the Cowichansite. This was due to a higher proportion of rottenmaterial and a larger average piece size on theSooke site. Moisture retention in large. rOllen piecesis greater than in small. sound pieces. It should benoted that 43% of the material processed at Sookewas rOllen. compared to only 17% at Cowichan.Furthermore. 57'};, of the material processed atSooke was greater than 28 centimetres in diameter.compared to only 17% at Cowichan.

The higher moisture content resulted in signific­antly lower calorific values for the material processedat the Sooke site.

Another reason for the lower calorific value of theSooke material could be the presence of a higherproportion of non~combustible inorganic material.This is indicated in the higher ash content of theSooke material. The higher inorganic content re­sulted from quantities of dirt collected with the re­sidues during the collection phase. Dirt tended toadhere to the residue material in greater quantitieswhen the material was wet. At Cowichan the mate·rial was generally drier. as were weather conditionsat the time of collection. From the results of thelaboratory analysis of processed material samples. itis possible to make several general conclusions.These conclusions are somewhat tentative. due tothe limited number of samples collected. Tables 19through 22 illustrate the relationship of calorificvalue to a number of factors.

There is significant loss in calorific value as wooddeteriorates. Table 19 shows the average calorificvalue of air dry samples in varying degrees ofdeterioration.

Moisture content has a large effect on calorificvalue of the processed material. Table 20 shows therange of calorific values that were obtained for sam­ples of sound and rotten wood of varying moisturecontents.

There appeared to be lillie variation in calorificvalue between samples of different tree species. Forair dried samples of sound material with similarmoisture content. the range of calorific values ob­tained is shown in Table 21. The range of calorificvalues for oven dried samples also showed littlevariation among species. The range for all speciessampled was 20.400 to 20.700 KJ/kg for oven driedwood.

There appeared to be little variation in calorificvalue between samples taken from different compo­nents of the tree. Table 22 shows the range ofcalorific values obtained for air dried samples ofsound material with similar moisture content.

The ratio of organic to inorganic material washigher in sound wood than in rotten wood. This is

46

Table 18 . Summary of Laboratory Analysis Results

Moisture Content

(";, of lolal weight)

Ash Content

(";, of oven dried weigh!)

Organic/Inorganic Ratio

(";, organic) based"~ inorganicon air dried sample weigh!

Calorific Value - Air Dry(net heat released inbuming air dried samplel

Calorific Value - Oven Dry

(net heat released inburning oven dried sample)

SookeSite Cowichan Site~ %~

Average (a) 60.9 56.5Low 53.7 39.4High 71.0 69.2

% %Average (a) 0.8 06Low 0.3 05High 2.0 08

Ratio Ratio

Average (a) 0.639 0798Low 0.369 0428High 0.833 1.495

Kd/kg (b) KJ/kgAverage (a) 7.000 8.100Low 3.000 4.600High 9.500 12.300

K.J/kg Kd/kgAverage (al 17.200 19.500Low 10400 16.200High 20.700 20.900

(a) Nunwocal A~'erq of sampiescoDe<:ted(b) KlIoJOUI~pel luIogrilm

Table 19 . Relationship of CalorificValue to Condition of Wood

Condition of Sample

Rotten WoodPartially RoHen Wood

Sound Wood

A\lerage Calorific ValueKd/kg

4.0005.8009.000

Table 20· Relationship of Calorific Value to Moisture Content

Sound WoodMoisture Content Calorific Value

~o Kd/kgo(aJ 20.50039 12.35055 9.00059 8.300

(alOvendry

Rotten WoodMoisture Content Calorific Value

% Kd/kgo(a) 14.70065 5.80068 4.10071 3.000

47

Table 21 . Relationship of Calorific: Value to TreeSpecies At Appro:ll.imately 55% Moisture Content

Species

Hemlock - BalsamFir

Ceda,Alder (3)

Average Calorific ValueK.J/kg

9.0508.8008.9009.050

(3) C~lorifk v~lue for r ~t 55'';, Moisture Contem ....as I!>;rrapolato?d from Iilbofalo~' af\o)~~ ddta

8.850

8.925

Table 22 . Relationship of Calorific Value to Tree ComponentPortion of Tree Moisture Content Calorific Value

% KJ/kg

56.2 9.05055.1

54.553.9

54.853.7

Stem Wood (Cedar)Stem Wood (Hem-Ball

Branch Wood (Hem-BallBranch Wood (Ar)

Slump and Roots (Fir)Slump and Roots (Hem-Ball

again due to a high moiSfure content in [he rottenwood.

Ash content was higher in ronen material than insound material. This was due to din that adhered tothe wetter rotten wood during the collection phaseand to a higher proportion of non-combustibles inthe rotten wood.

Samples of the processed material from theNicholson chipper were analyzed at Crofton PulpMill to determine the distribution of chip sizes. Virtu­ally all the material sampled was well within theacceptable size limits for the Crofton pulp mill hogfuel boiler (0 to 200 millimetres). This boiler uses amoving grate burner 10 produce process steam forIhe pulp and paper mill. Indications were thai theCowichan site malerial was compatible with theburner feed mechanism and burned well. with linleor no residue.

Ahhough no lonnal size dismbution analysis wascarried out on the processed material from the Bart­len chipper. the average chip size was considerablylarger than at Cowichan. HOVJever. as with theNicholson chipper. most of the chips were within theacceptable size limits for the hog fuel burner.

Chips from the Nicholson and Bartlen chippersvaried considerably in size. depending on the condi­tion of the chipper knives. Generally. as the knife

edges became dull. the chip size increased. Whenknives were sharp. Ihe chip size from the icholsonmachine was uniform. the maJOrity 01 chips (60 to70";, by weight) falling in the ID-to-SO-millimetresize range. Dull knives frequently produced large"card" chips up to 200 millimetres in length. Theapproximate piece size distribution of the processedmaterial from the Nicholson chipper with sharpknives. is shown in Table 23.

The Bartle" chipper produced a much more vari­able size of chip. Prior to the installation of chipbreakers. piece size frequently ranged up to 200millimetres. The number of large pieces was sub­stantially reduced through the use of chip breakers.With sharp knives and chip breakers installed. thedistribution of chip size was as shOVJr1 in Table 24.Photographs of the processed material from bothtypes of chipper are included in Appendix 3.

The density of the material produced was de­(ermined from weights and volume measurementscarried out during the transportation mats. The aver­age density of the material produced by the Bartlettchipper was 200 kilograms per cubic metre. Theaverage density of the material produced by theNicholson chipper was 228 kilograms per cubicmetre. The higher density of the Nicholson materialwas due to compaction caused by the blower and tosmaller chip size.

48

Table 23· Nicholson Chipper - Approximate Chip Size Distribution

Size Class(Millimetres)

0- 55 - 10

10-3030T

ProportionalDistribution

20%15%50%15%

Table 24 . Bartlett Chipper - Approximate Chip Size Distribution

Size Clalis(Millimetres)

0- 5050 - 100

100 - 150150 +

ProportionalDistribution

300/050%15%5'"'"

Table 25· Energy Consumed by Operational Phase

Operational Phase

Residue CollectionResidue ProcessingSubtotal - Collection and Processing

Transportation of Processed Material (3)

Total (Collection Processing and Transport)

Sooke Site(MJ/Tonne)(b)

74782856296

1.152

Cowic::han Site(MJ/Tonne)

54759813

99

912

(3) Estimilwd energy consumption. based on transportiHion of millen,,1 from both sites to the hog fuel boikr ill Crofton using a chip Vdn

with a 10 tOllne lXlylo<ld. 500ke Site to Crofton 75 km: C<)V.lichan site to Crofton 25 km.

(b) Meg3]'Ouies per tonlle,

5.6 Energy Consumed versus En­ergy Produced

During the course of the field tests. records werekept of fuel consumed by all equipment used incollecting, processing and transporting the materialproduced. These fuel consumption data were con­vened to equivalent energy consumption, using theappropriate energy value for the fuel used. The en­ergy consumed in each phase of the project wasrelated to the quantity of logging residue handled inthat particular phase. The energy consumed pertonne of material produced is summarized for bothtest sites in Table 25.

Representative samples of the material producedwere analyzed to determine the potential energy

value available. As expected. the results of thisanalysis indicated a significant difference in energypotential between rotten and sound wood. as well asbetween woods of varying moisture content. Energyvalues were applied to the proportion of materialproduced in each category to determine the weigh­ted average energy value per tonne, The unit energyvalue per tonne of material produced at the Sookeand Cowichan sites is summarized in Table 26.

The energy value of fuels consumed in collecting.processing and transporting the logging residuesfrom both sites was compared with the energy po­tential of the material produced during the tests. Theunit value of energy output to energy input for bothsites is summarized in Table 27.

49

Table 26 . Energy Value Potentially Available from Material Produced

Material Type SookeSite Cowichan Site

Species Condition Average Average(a) Averilge Average(a)Moisture Proportional Energy Moisture Proportional EnergyContent Distribution Value Content Distribution Value

('ra) (%) (MJ/ (~) (%) (MJ/Tonne) Tonne)

Conifer Rotten 70 11A 3.840 69 4A 4.750Conifer Panially Ronen 64 34.1 5.630 65 133 5.930Conifer Sound 55 54.5 9.300 55 69.3 8.700Deciduous(bl Sound 39 130 12.350Weighted Average 60 1000 7A25 55 100,0 8.630

(a) &S<!d on laboratory <lnillysl5 of repreS<!ot<llive ,;amples collected and t€'Swd in ilir dry condition

(b) Prilllilnly Alder

Table 27· Summary of Unit Values of Energy Consumed Versus Energy Produced(Megiljoules(fonne)

SookeSite Cowichan SiteOperational Phase In(a) OutCb) Ratio In(a) Out(h) Ratio

(Out/In) (Outlln)

Residue Collection 74 7A25 100.3 54 8.630 159.8Residue Processing 782 9.5 759 11.4

Collection ~nd

Processing 856 7.425 8.7 813 8.630 10.6

(~lln Energy Value of Fuel Consumed

(b) Out'" Weighted Average Potential Energy V<llue of Processed ResKlues.

The reasons for the consistently higher energyOUlput to input ratio for the Cowiehan site are:

• M~terial on the Cowichan site had a subslanti~lly

higher average energy potential than !hat on theSooke Site. This is primarily due 10 1oo.ver moisturecontent of the Cowichan material.

- Residues ~I Cou.richan consisted of smaller. lighlerm~teri~1 than those at Sooke. In addition. the col·lection of m~terialon Ihe Cowich~n site was carriedout on relatively flat. dry ground. requiring lessenergy consumption 10 collect the logging residuesthan on the steeper Sooke site. The Cowichan sitealso had lower stumps ~nd lighter debris concent·ration. which resulted in higher productivity in the

collection operation.- AI Cowichan. Ihe relatively flat 10(X)gfaphy enab·

led the construction of access roods to loggingresidue assembly points located throughout Ihesite. Thus. the average distance over which mate·rial w~s rransported to these assembly points wasless than at the Sooke site. This resulted in lessenergy consumption per lonne collected.

• Organization and operating efficiency of the con­tractor at Cowiehan was superior to that of thecontractor who carried oul the Sooke tests.

- Average processing productivity at the Cowiehansite was 17.5 tonnes per day, compared to 8 to 10lonnes per day at Sooke.

50

6. CONCLUSIONS ANDRECOMMENDATIONS

6.1 Assessment of Methods Used

a. Inventory

A quick. approximate estimate of the quantityof residues present on the site was obtainedthrough the use 0/ the U.S.D,A Photo Series forQuantifying Forest Residues (Maxwell and Ward.1976).

The line-intersect method of samplingdowned. woody material (Brown. 1974) gave agood estimate of the quantity of residue by size.species and condition. The method is simple. fastand easy to apply. Itenab[es advance estimates tobe prepared for planning of residue collection andprocessing operations.

The line-intersect sampling inventory carriedout on ENFOR project test sites showed an aver­age residue quantity of 185 lannes per hectare atSooke and 5S lannes per hectare at Cowichan.

b. Collection

The use of small crawler tractors to collect log­ging residues into piles prior to processing re·suited in a good percentage recovery with aminimum of ground disturbance. The materialcollected by this method was relatively free of din.

At Sooke. gound conditions were moderatelysteep and chipper access was confined to theexisting logging road. All residue material wascollected into a windrow along the existing log­ging road. Average collection distance was 50metres. At Cowichan. where topographic condi­tions permitted the construction of chipper accessroads into the area. the average collection dist­ance was reduced by collecting residues into anumber of piles scattered throughout the testarea.

An inventory carried out following residue col­lection showed that the percentage recovery var­ied with piece size. The average recovery of mate­rial included in the original inventory ranged from70% in 0.6-2.S-centimetre diameter material to8001

0 in 2.6 to 7.6-centimetre diameter material to940/0 in material greater than 7.6 centimetres indiameter. The overall average recovery was 85%at Col.-llichan and 94% at Sooke.

Costs of collection ranged from .::5.89 pertonne at Cowichan. where the topography wasrelatively flat and piece size was small, to .::9.10per tonne at Sooke. where the ground was mod­erately steep and many large pieces wereencountered.

c. Processing

It is difficult to compare the two chippers owingto the completely different nature of the loggingresidue material on the two test sites. In tenns oftheir ability to process all of the available materialthe Bartlett chipper was able to handle 85% of thematerial. compared to 70°;" for the Nicholsonchipper. In terms of productivity. the Nicholsonchipper produced an average of 17.5 tonnes perday. compared to the Bartlett chipper's averageof 8.5 tonnes per day. Based on productivemachine hours. the productivity for the Nicholsonchipper was 4.7 tonnes per productive machinehour. compared to 3.2 tonnes per productivemachine hour for the Bartlett chipper.

Costs for the Sooke operation averaged about$48 per tonne for chipping and $22 per tonne forsplitting and fon.varding. for a total processingcost of $70 per tonne. At Cowichan, chippingcosts. including construction of access roads. av­eraged $54 per tonne and forwarding costs were$16 per tonne. for a total processing cost of $70per tonne.

The trials at Sooke proved the usefulness of thestump splitter to cut large stumps into smaller sizepieces and to release dirt and rocks in the rootsystems. However. the value of the stump splitterfor cutting large logs and saplings into shorterlengths was very limited. In most cases. a chainsaw would have perfonned this function moreeffectively at a much lower cost. If stumps are notto be recovered in logging residue halVesting op­erations. no stump splitter will be required.

The Bartlett chipper proved to be capable ofhandling all sizes of material. but its productivitysuffered due to frequent and lime consumingbreakdowns. Obviously many refinements are re­quired before this machine can be considered asan operational. rather than a prototype. model.Chipper modifications carried out on this projectdealt with a number of the originallimilations ofthe machine. but there are many more problemsto be overcome. The infeed mechanism shouldundergo major modifications to enable materialto be fed independently without the constant at­tention of the operator. The outfeed mechanismshould also be changed to overcome blockageproblems associated with branch material and toenable loading of vans positioned end to end withthe chipper rather than alongside. The side load­ing feature of the present machine limits its use tovery wide. flat areas. which are not frequentlyfound on forest operating sites.

On both sites. experience showed that a smallcrawler loader equipped with a brush grapple orlog forks should be used to assist the chipper. Theloader proved very useful for fowarding. sorting

51

Table 28 . Summary of Production Costs

Production CostsItem

Residue CollectionResidue Processing

Total

Sooke Site($/tonne)

9.1070.10

79.20

Cowichan Site($/tonne)

S896981

75.70

and bunching material for the chipper. Withoutthis equipment. the chipper grapple would havedifficulty in assembling sufficient residue materialto fully utilize the chipper' 5 productive capacity.

6.2 Summary of Production Costsand Revenuesa. Costs

The costs of collecting and processing forestresidues. based on information gathered duringfield trials at Sooke and Cowichan. are sum­marized in Table 28.

Collection and processing costs are based onactual costs incurred on the project. excludingthose costs associated with project mobilizationand demobilization. As the sites were chosen tobe representative of moderate slope logged-overareas on Vancouver Island. similar costs could beexpected under similar operating conditions. us­ing the methods described.

Transportation costs were estimated. based onfield experience and on the followingassumptions:

Processed material from both sites would betransported to B.C. Forest Products' CroftonPulp Mill in 10 tonne capacity trailers.

- A spare trailer would be used to eliminate theneed for the truck and driver to wait during theloading phase.

~ One-way distance to Crofton from: Cowichansite - 25 km: from Sooke site - 75 km.

Based on the above assumptions. the cost ofprocessed material transportation is estimated tobe $ 13.26/tonne from the Sooke site and $5.63/tonne from the Cowichan site.

b. Reyenues

To determine the possible revenues from thesale of processed logging residues. the currenthog fuel selling price was examined. The currentselling/purchase price of hog fuel utilized on Van­couver Island is little or nothing. The purchasergenerally acquires hog fuel for the cost of deliv­ery. Hog fuel used for the production of steam

and power is costing the user $2.50 to $6.75 perunit. delivered to conversion plants on the SouthCoast of B. C. Net income to the selling mll! rangesbetween a loss of $2 per unit to a profit of $2 perunit. depending on proximity to the conversionplant (Appelby 1978). These low revenues to theproducer reflect a surplus of mill residues andrepresent an attractive alternative to disposalcosts which currently range from $2 to $7 perunit.

Crofton Pulp and Paper Division pays $3 perunit (about $2.75 per tonne) for hog fuel deliveryto their boiler facility. This hog fuel comes fromsawmills located within about a 50 kilometreradius and is produced as a waste product ofsawmilling operations. The difference betweenpresent forest residue production and deliverycosts ($80-$90 per tonne) and the deliveredvalue of this material ($2. 75/tonne) is such that itwould not be economically feasible to use loggingresidues as an energy source at this time. Thissituation may change if the present hog fuel surp­lus diminishes and comes into balance with us­age. This has been predicted for the south coastregion of B.c. by the early 1980s (B.c. Wood­Waste Energy Coordinating Committee 1978),when present and planned construction of woodfired boilers at several pulp mills on the southcoast is completed.

c. Value of Processed Material in Terms ofAlternatiye Fuels

One measure of the value of wood residues asa fuel source is in terms of the equivalent value offuel oil. A rough comparison was made to de­termine the quantity and value of fuel oil whichwould provide an amount of potential energyequivalent to one tonne of forest residues. Thebasic assumptions of this comparison are listedbelow.

- One tonne of sound. processed forest residuewith a 55% moisture content would have apotential energy value of9.000 megajoules.

- One litre of #2 fuel oil would have an approxi­mate energy value of 40 megajoules (Hensel19781.

- Therefore. one tonne of sound processed forestresidues would have a potential energy valueequivalent 10 abaut 225 litres of fuel oil.

- Bulk price of #2 fuel oil in Vancouver. RC.January 1980. was 15.4 cents per litre.

- Therefore, in tenns of equivalent potential en­ergy value. wood residue has a present value ofabout $35 per tonne.

This comparison does not take into considera­tion the following factors:

- Burning EfficiencyOil fired boilers commonly achieve net boilerefficiencies of 80 to 85"'0. while wood fired boil­ers commonly have net boiler efficiencies in therange of 65 to 75"iJ depending on the moisturecontent of the fuel (Curtis 1978).

- Capital Cost of BoilersBecause of the bulky nature and high moisturecontent of wood fuels. steam plants using woodfuels cost considerably more than plants usingoiL Costs of wood fuel boilers are two to fourlimes more than oil fired boilers (S,H. Leveltonand Associates 1975).

- Operating CostThe cost of operating wood fired boilers is higherthan oil fired boilers. due to the extra personnelrequired to maintain and operate the feedingand ash recovery mechanisms.

[n summary, wood residues have an apparentpresent value of $35 per tonne in terms of poten­tial energy. However, due to the high cost ofbuilding and operating wood fired boilers and alow net boiler efficiency. this value in terms ofequivalent net energy produced in comparisonwith oil would be considerably lower.

Present surplus hog fuel supplies from existingwood using conversion plants have resulted in amarket price of about $3 per tonne. This barelycovers production and transportation costs but isacceptable to the producers, who look upon thisrevenue as an offset to their disposal costs. Whilethis situation exists there is little hope for aneconomically viable system for utilizing loggingresidues as a source of energy.

Based on a calorific value of9000 MJ/tonne forprocessed forest residues and a calorific value of40 MJ/litre for oil, a graph (see Fig. 16) wasconstructed relating the monetary value of re­sidues to oil price. Line A on the graph shows therelationship between residue value per tonne andoil price per litre over a range of oil prices. Ontothis graph was superimposed the relationship ofresidue production and delivery costs to oil costbased on fuel consumption information collectedduring field trials. This second relationship is il­lustrated by Line B on Figure 16.

52

The point at which delivered processed mate­rial cost is equal to the monetary value of thematerial produced is at a point where oil costs are$0.40 per litre. This means thai until oil costsreach a point in excess of $0.40 per litre. it will notbe economically feasible to utilize logging re­sidues as replacement fuel for oil. Actually. due tothe higher cost of building and operating woodfired boilers and their lower combustion effi­ciency. the cost of oil would have to be consider­ably higher than $0.40 per litre before loggingresidues could be economically salvaged andutilized to replace fuel oil.

Line C on Figure 16 illustrates the same rela­tionship between delivered cost and equivalentvalue of logging residues for a modified opera­tional processing system. This system is discussedin section 6.4 and cost estimates are illustrated inTable 30. Line C shows that if delivered cost canbe reduced to $50 to $55 per tonne, the point ofequal cost and value will be at an oil cost of $0.24per litre.

6.3 Future Research and Develop­ment Requirementsa. Logging Residue Inventory

To identify and evaluate potential source areaswhere the utilization of logging residues may befeasible. more information is required on the na­ture. volume and location of logging residues. Asystem is required to predict the quantity and typeof residues that can be expected to remain follow­ing logging. This system should take into consid­eration the nature of the forest. topography andmethod of logging to be used.

b. Source Areas

Studies such as that carried out by Paul H.Jones and Associates (1979) to assess the vol­ume. location and availability of wood biomassfrom the forest areas of Vancouver Island shouldbe done for other geographic areas. Comparativestudies of logging residue availability and costwith power and process steam requirementsshould be done on a regional basis. This wouldenable the indentification of areas where loggingresidues could be used to satisfy specific localenergy requirements.

c. Materials Handling Systems

More efficienl methods of harvesting and trans­porting logging residues should be investigated.In particular. research efforts should be directedtoward the development of harvesting methodsfor steeper slopes and a one-pass system to re­trieve logging residues and merchantable logs in asingle. joint operation. This research should inc­lude the development of systems for separating

~

:;J<:

~

Figure 16 - Relationship of Delivered COSI and Equivalent Valueof Logging Residues to Changes in Diesel and Fuel Oil Prices.

6•"•<•c

100

j

9080RESIDUES

60 70OF PROCESSED tOGGING

($/TONNE)

"?~..:~..c:~..0\'\"

i0l""\l \,-\.o\)£. -

..."",-<;J\l"'vcf,C,,-'i<C

i;j--i!I

E!J~t!>-;

"''"'"

50COST/VALUE

40

'v,-'i<" '

0.10 1 • , I I I I I I

30

0.5

~ 0.4....0:o.

r;]i:~

"'~:Ji ~O.J"' ­.... ~"'~-"'....o

"'"'i: 0.20

LINE A. VALUE OF LOGGING RESIDUES IN TER!'lS OF EQUIVALENT VALUE or rUEL OIL

LINE B. AVERAGE DELIVERED LOGGING RESIDUE COST - PROJECT TEST SITES TO CROFTON PULPHILL

LINE C. ESTUlATED DELIVERED LOGGING RESIDUE COST - !'IODIFlED OPERATIONAL PROCESSING $YSTEH

and handling of these two types of material onsteep forest sites under the limitations imposed bythe narrow roads.

On flatter sites. a self-propelled chipper couldbe used to process logging residues piled at pointsdistributed throughout the logged-over area. Thissystem would eliminate the need for chipper ac­cess roads. as well as reduce residue collectioncosts by shortening the distance over which re­sidues must be camed to a concentrating point. Aself-propelled chipper would have the advantageof improved manoeuverability and lower systemcost than a chipper that depends on a separatetruck for its mobility.

The system of feeding residue material into thechipper requires refinement. A major limitation ofexisting equipment is the slow. cumbersomefeeding of small branch and top material. usingthe hydraulic log grapple. This equipment wasdesigned to handle large diameter. long lengthpieces. Because of the time involved to handlethe many small volume pieces. the grapple can­not supply a sufficient quantity of material to fullyutilize chipper capacity. This results in a very lowsystem productivity.

A system of bulk loading piled slash into thechipper is reqUired in order to more fully utilizethe productive capacity of the chipper. A slopedvibrating screen placed ahead of the chipper in­feed mechanism would remove most rocks anddirt from the residue material while ensuring asteady feed of large quantities of material to thechipper. Another pOSSibility for improving pro­ductivity would be to compress the branch andtop material into bales prior to chipping. Thecapacity of the chipper could be more fullyutilized in chipping bales and there would be noprotruding pieces 10 cause infeed blockages,

Processed material loading and transportationmethods and equipment could also be improved.The optimum transportation system may involvethe use of trucks with detachable. interchange­able chip containers. These box type containerscould be of/-loaded and left with the chipper forloading. The truck could pick up loaded chipcontainers and return to the conversion plant.thus eliminating unproductive truck waiting time.Single chip containers could be hauled on smallmanoeuverable trucks on the forest road portionof the route and then transferred to tandem trail­ers capable of hauling several containers on thehighway portion of the route.

Chip containers or other fonns of load camershould be designed to be compatible with theparticular chip discharge system of the chipperand with the unloading system to be employed atthe conversion plant.

54

For off-road chipping systems. a fOlWardervehicle would be required to move loaded chipcontainers to road-side. Possibly a combined re­sidue collection and container forwarder vehiclecould be developed.

d. Processing and Product Technology

From experience gained during the field trials.it is clear that further development work is re­qUired on processing equipment in order to over­come problems associated with:

Chipping of small diameter and short lengthmaterial.

- Sensitivity of knives to damage and excessivewear caused by rocks and dirt,- Productive time losses due to knife changing

and maintenance.- Productive lime losses due to blockages of in­

feed and outfeed mechanisms.

Further research and development is requiredto determine the optimum shape and size of fuelchip. Present equipment. such as that employedon project field trials. was not designed to pro­duce a specific product for a particular energyconversion process. Different types of burningsystems (fluidized bed. moving grate. suspension.etc.) would likely require fuel chips of varying sizeand shape. Similarly. if the processed forest re­sidues are to be pelletized. the fuel chips pro­duced should be compatible with the pelletizingequipment to be used.

Further research to determine the optimumpractical moisture content of fuel chips is alsorequired. Perhaps the use of pre-driers or bailingequipment to squeeze moisture out of the chipswould be justified in order to achieve higher com­bustion efficiencies.

Further information is required on the burningcharacteristics of decayed wood, Since a largeportion of logging residue material is not presentlyutilized. due to decay. more information on thissubject is required. Perhaps through the additionof other substances during the combustion pro­cess the burning characteristics of rotten woodcould be enhanced.

e. Marketing Procedures

Forest residue utilization technology will beginto evolve when the value of wood residues incomparison with other competing fuels becomessuffiCiently high to cover the cost of collecting.processing and transporting this material to anenergy conversion facility. [n preparation for thispoint of value-cost equilibrium. studies should beundertaken to detennine methods of marketingprocessed forest residue material to bothdomestic and industrial users. The direction ofmaterials handling and product technology will.

55

to a large extent. be governed by the marketswhere the processed material will be utilized.

f. Forest Policy and Wood ResidueUtilization

As more energy users convert from traditionalfossil fuels to \.V()()(j residues it is probable that millresidue supplies may not be sufficient to meetdemand. AI that time. the focus of anention mayshift to logging residues as a supplement to millresidues. In order thai the removal and use oflogging residues from crown land be regulatedand allocated to the optimum end use. new forestpolicy regarding wood residues must be pre­pared. This may involve new legislation coveringsalvage rights. stumpage payments and a policyof fuel chip direction and allocation similar to thatnow in effect for pulp chips.

6.4 Concept for CommercialApplication

Production costs could be reduced by alteringcertain organizational aspects of the systems de­veloped and tested on this proJeCl The systemtested used a two-phase concept for collection andprocessing. By carrying out both operationssimultaneously. the amount of equipment requiredcould be reduced.

One chipper could work together with one to twosmall crawler tractors as a production unit. The landdearing machines would be used to collect sufficientmaterial for the chipper. assist the chipper duringmoves. position chip containers and carry Oul roodand landing maintenance as required. A landing­man with a power saw would be required to buckover-sized pieces and roots suspected of conlainingrocks. He would also assist the chipper operalor indearing blockages and changing knives_

Transponation could be handled by chip contain·ers (10 tonne capacity). which could be dropped offin the landing and picked up by a truck when full. II isestimated that Ihree to four of these containerswould be required. depending on the distance fromthe operating area to the energy conversion plant.As the truck would likely not be required on a full­time basis. the use of contract trucks on an "asrequired" basis is recommended. Containers couldbe loaded onto the truck. using the crawler trador ora winch system mounted on the truck.

Larger capacity trucks or truck-trailer units cap­able of handling two or more 10 tonne chip contain­ers l.IJOuld result in a loI.ver transportation cost. How­ever. the use of larger trucks would likely be im­practical because of lack of space in landings. IoI.vstandard roads and traffic congestion in active log­ging areas.

Equipment and labor requirements and estimated

costs for the system outlined above are listed inTable 29. The cost of collection and processing isestimated to be $57.50 per tonne. Transportationcosts would vary with distance and would rangefrom 7 to S12 per tonne for a total delivery cost of 65to $70 per tonne.

A key factor in improving system costs is to speedup the handling of small diameter. short-length re­sidue material. Studies carried out in Sweden (Dan­nielsson 1977) investigated the use of bundling de·vices for compressing and tying residues prior tochipping. Field trials showed a marked increase inproduction through more complete utilization of thechipper infeed mechanism and reduce infeedblockages. By increasing the volume of material fedinto the chipper per unit of time. daily productionwas jncreased by up to five times over that whenfeeding loose material. A production increase of thismagnitude would reduce collection and processingsystem costs from the estimated $57.50 per tonne asshown in Table 29 to about $30 per tonne.

More realistically. it is likely that prebaling of smallresidues l.IJOuld double chipper output. thus reduc­ing the processing portion of the system cost byabout 50%. However. the additional cost of prebal­ing must also be considered. It is estimaled that thetotal collection and processing cost. using a prebal­ing concept would be $42.50 per tonne. as shown inTable 30. Total delivered cost using this systemwould be 50 to $55 per tonne.

The previous discussion indicates thai prebalingof residues in order to increase processing productiv­ity would result in a reduction of about $IS pertonne in the total delivered cost of processedresidues.

The author investigated the cost of collecting re­sidue material along with merchantable logs in oneoperation. Residue collection costs for single passyarding were estimated by Jones (1979) to be 10 to$12 per tonne. based on highlead yarding of re­sidues in conjunction VJith primary logging. This costreflects the steep. rough terrain typical of highleadyarding sites on Vancouver Island. On flat or gentlysloping land. wholetree skidding to recover residuesalong with merchantable logs is expected to cost 8 to510 per tonne.

Possibly costs could be reduced by collecting andprocessing only the larger diameter logging residues.These larger pieces would result in higher systemproductivity and thus lower costs. HOlAIeVer. thelarger diameter logging residues would likely bethose with the least energy value. due to a higherproportion of ronen wood. [I is also possible thatmany of these larger pieces could be transportedalong with merchantable sawlogs and processed in amill waste-wood chipper more economically than byfield chipping.

56

Table 29 . Cost Esomates for an Operational Forest Residue CoUection. Processingand Transportation System

Collection and Processing

Equipment1 Crawler Tractor (SO kw) With Brush Blade1 Nicholson Complete TTee Utilizer1 Power Saw

Estimated Owning and Operating Cost:

LabmI Chipper Operator1 Crawler Tractor Operator1 Power Saw Operator/Landing Man

T01031 Equipment and LaborEstimated Collection and Processing Productivity

Collection and Processing - System Cost

Transportation

Equipment and Labor1 Contract Truck (with operator)3 Chip Containers (10 tonne capaciry)

Total Equipment and Labor

Transportation Cost O· 50 kmSO-loo kmlOO-I50km

Talai Delivered COSI (rounded)

S 750/day

$ 400/day

$ 1.150 Iday20lcnnes/day

$57.50 !Ionne

S 200/dayS 75/dayS 275/day$ 7/lonne$ 9 tonne$ 12/tonne$65-70/tonne

Table 30· Cost Estimates for an Operational Forest Residue Collection, Prebaling, Proces­sing and Transportation System

Collection, Prebaling and Processing

Equipment2 Crawler Tractors (50 kw) with Brush BladesI PrebalerI Nicholson Complete Tree Utilizer

Estimated Owning and Operating Cost:

Labm2 Crawler Traclor Operators1 Chipper OperatorI Landing Man (to operate ?rebaler and PO\lJer Sawl

Estimated Labor CostTotal Equipment and Labor

Estimated System Productivity

Estimated System Cost

Transportation (as in Table 29)

Total Delivered Cost

SI.250/day

$ 550 day

$I.800/day40-45 lonnes/day

$42.50/tonne

S 7-12/tonne

S50-55/tonne

In spite of possible cost reductions through modifi­cations in the residue processing system. the collec­tion and utilization of logging residues would not becommercially feasible at Ihe presemlime. due 10 thelarge unfavorable difference bet\veen revenue andcost. Revenues wtll continue to be low for sometime, owing to a surplus of wood residues availablefrom wood processing plants. Mill residues are pre­sently treated as waste products and therefore carryno share of the logging and transpon costs incurredin delivering them to the mill. The value of these millresidues is presently considered to be only the cost ofprocessing (in most cases hogging) and transpona-

57

tion. which currently varies from 2.50 to $5.00 perunit (approximately 2.30 to S4.60 pergreen tonne).

In summary. il would appear that although fieldprocessing of forest residues is technically feasible.the commercial application of methods developedand tested on this projecl would nol be economicallyfeasible at this time. This may change as more ccstefficient methods of retrieving and processing log·ging residues are developed. as the surplus of millresidues comes into balance with demand and as theprice of alternative fuels increases.

REFERENCES

Appleby. P.W. 1978. Hog Fuel Availability Study· SouthCoastal Region of B.C B.C Wood Waste EnergyCoordinating Comminee, Vancouver. B.C. 38 p.

Brown, J. K. 1974. HaflClbook for Invenlorying DownedWoody Material Intermountain Forest aflCl Range Ex­periment Station. Ogden. Utah, USDA. Forest SetvkeGeneral Technical Repon INT· 16. 24 p.

Cunis. A.B. 1978. Fuel Value ukulator. USDA. ForestService. Southeastern Area Infonnation Centre. At·lanta. Ga.

Danielssorl. B.C 1977. Compressing Small Trees andTree COtlllX:ments. Swedish University of AgriculturalSciences. College of Forestry. Depanment of Opera­donal Efficiency Garpenburg. Sweden. Repon No.119 1977.

FAO. Rome, 1976. Wood Chips Production. Handlingand Transpon (Second edition). oIWl?gian Funds inTrusI.FOI:TF-INT55A( ORI.I36p.

Harrison. R.T. 1975 SLASH ... Equipmenl andMethods for Treatment and Url1lzation USDA. ForestService. Equipment Development Centre. San Dimas.California. Equipment Development and Tesl Report7120-7. 47p.

Hensel. J.S 1978. Wood as a Fuel. American Pulpo.A.·oodAssociation. Washington. D.C. Technical Release No.78-R-16 5 p.

Jones. P.H. 1979 Erwrgy from Fores! Biomass on Van­couver IslaflCl_ Pacific Forest Research Centre. VICtoria.B.C. Report BC-X-197 67 p.

Levellon. B.H. 1975. An Evalualion of WOlXi-Wasle En­ergy Conversion Systems. Western Forest ProductsLab.. Vancouver. B.C. 185 p.

Levelton. a.H. 1975. Combustion Technology for theDisposal and Utilization of Wood Residue. Environ­ment Canada. Environmental Protection Service.Economic and Technical Review Report EPS 3-AP-75­4. 92p.

Maxwell. G.M. and F. Ward. 1976. Photo Series forQuantifying Foresl Residues. PacifIC Nonh\l:esl Fores!and Range Experiment Station. Porlland. Oregon.USDA, Fares! Service. General Technical ReponPNW-SII03p.

Wenon. EA.F. 1976. Logging Residues in British Colum­bia. Special Siudies Division. B.C Forest Service. VIC­toria. B.C. 94 p.

58

APPENDIX 1 • TERMlNOLOGY AND CONVERSION FACTORS

TERMINOLOGV

Logging Residues - For the purposes of this study logging residues refers to all loose woodymaterial remaining on the ground following logging operations. This malerial is commonlycalled slash.

Processed Material - This refers 10 the material produced by the chipping equipment used onthe project. Sometimes referred to as fuel chips 10 distinguish from pulp chips or hog fuel.

Hog Fuel- Refers 10 mill wood waste processed by hogging equipment which tears. crushes orbreaks wood rather than cutting.

Residue Loading - The term loading in conjunction with logging residues refers to the quantityof residue per unit area of logged over land. In this report the unit of measure for loggingresidue loading is lennes per hectare.

Chip Breaker - A knife set into the main chipper knife holding mechanism to further split thechip into smaller pieces.

Tonne - All logging residue measurements in this report are based on air dried metric lonnes.

BOTANICAL NAMES OF SPECIES REFERRED TO IN REPORT

Common Name

AlderBalsamCedarFirHemlock

Botanical Name

Alnus rubra (Bong.)Abies amabilis (Dougl.) ForbesThUja plicata (Donn)Pseudotsuga menziesii (Mirb.) FrancoTsuga heterophylJa (Raf.) Sarg.

Conversion Factors

The follOwing table lists the factors used 10 convert impenal units to metric units.

Multiply By To ObtainMeasure Imperial Unit Conversion Factor Metric Unit

Length inches 254 centimetresfeet 0.3048 metresmiles 1.609 kilometres

Area acres 0.405 hectares

Volume (solid) cubic feet 0.0283 cubic metresunits (200 n3) 5.663 cubic metres

Volume (liquid) gallons 4.546 litres

Weight pounds 0.4536 kilogramstonnes 0.907 tonnes

Energy horsepower 0.7457 kw (kilowatts)BTU 1.0544 KJ (kilo.lOules)

59

APPENDIX 2 . LOGGING RESIDUE INVENTORY

Calculations of Weight per HectareFrom Inventory Data

The basic formula used to obtain weight per hectare as derived by James K. Brown in his Handbook forInventory Downed Woody Material is as follows

al Inventory for material in the 0.6 - 2.5 and 2.6 - 7.6 em diameter classes,!annes/hectares == 11.64 (n) (02) (s) (a) (e) NL2.2417

b) for material 7.6 + em in diameter:tennes/hectare == 11.64 (d2 ) (s) (a) (c)

NL 2.2417

Where:nDdsa,NL11.642.2417

= Number of pieces= Average diameter for the appropriate diameter class== Diameter of residue at point of intersection in inches= Specific gravityx= Factor for correcting orientation bias 0/ residual material= Slope correctionx= Number of plotsx= Length of transect line in feel== A derived constant~ Conversion factor for tons/acre to tonnes/hectare

60

APPENDIX3-

PROCESSED MATERIAL-

ANALYSES AND ILLUSTRATIONS

1. Report of Analysis - Sooke Site2. Report of Analysis - Cowichan Site3. Illustrations

Beak Consultants limited

Laboratoryl3851 Shell RoadRichmond/British ColumbiaCanadalV6X 2w2Telephone l604) 273-1601Telex 04-508736

REPORT OF ANALYSIS

Chent Forestal International Limited1550 Alberni StreetVancouver, S.c.V6G lA5

Attention: J. Blakeney

Sooke Site

Project: K4404/38

Dale received: 19 July 1979

Number of samples: 6/8

Sample reference

4368 4369 4370 4371 4372 4373

Moisture Content, % 64.8 53.7 55.1 54.5 56.2 63.7Ash Content (oven

Oried), % 0.67 0.87 0.31 0.46 0.44 0.72Calorific Value

(Wet), BTU/lb 2430 4015 4105 3900 3970 2410Calorific Value

(Oven Dried), BTU/1b 6730 8685 8920 8790 8845 6810Organic/InorganicRatio, Wet Basis 0.527 0.833 0.805 0.820 0.766 0.552

Ref 4368 Sooke Cedar Slab Partially Rotten 14/7/794369 Sooke Stump and Root Wood Sound - 16/7/794370 Sooke HemBal Stemwood SOUnd4371 Sooke Branchwood Mixed Species4372 Sooke Cedar. StelTMood Sound4373 Sooke HemBal 5temwood Partially Rotten - 14/7/79

All results expressed as mgJI exceptpH (Units). coliform (organismsf100 ml). color (units)conductIvity (umnos/cm). sallnlly (./•• ). turbidity (NTU)

Beak Consultants Limited

Laboratory/3851 Shell RoadRichmond/British ColumbiaCanada/V6X 2W2Telephone (604) 273-1601Telex 04-508736

REPORT OF ANALYSIS

Client Forestal International Limited Project: K4404/38

Date received: 19 Ju1y 1979

Number of samples: 2/8

Sample reference

4374 4375

Moisture Content, % 68.4 71.0Ash Content (Oven

Di red), % 0.94 2.03Ca1ori fi c Value

(Wet), BTU/1b 1750 1280Calorific Value

(Oven Dried), BTU/1b 5415 4510Organic/Inorganic

Ratio. Wet Basis 0.442 0.369

ReI- 4374 - Sooke Stump and Root Wood Rotten4375 - Sooke Rotten Old Windfall Stemwood

All results expressed as mg/I exceptpH (units\, col ilorm (organisms/1 00 mil, color (un its)conductivity (umhoslcm), salinity (~/o.l,turbidity(NTU) _/("( C--Le~

v

Beak Consultants Limited

Laboratory/3851 Shell RoadRichmond/British ColumbiaCanadalV6X 2W2Telephone (604) 273·1601Tele.04·508736

REPORT OF ANALYSIS

Client Forestal International Limited1550 Alberni StreetVancouver, B. C.V6G lA5

Attention: J. Blakeney

Cowichan Site

Project: K4404/38

Date received: 1 October 1979

Numberof samples: 6/7

Sample reference4455 4456 4457 4458 4459 4460

Moisture Content, % 58.7 39.4 55.1 69.2 54.8 64.5Ash Content (Oven

Dried), % 0.71 0.68 0.52 0.84 0.47 0.65Calorific Value(I,et), BTUIl b 3580 5320 3830 2040 3600 2550

Calorific Value(Oven Dried), BTUllb 8940 9020 8870 7030 8550 7490

Organic/InorganicRatio, Wet Basis 0.683 1.495 0.798 0.428 0.809 0.535

Ref 445544564457445844594460

Green Alder - Stem and TopDry Alder - StemCedar Windfall - SoundRotten (Punky) Fir WindfallFir Saplings with Root WadPartially Rotten Fir

All results expressed as mg/l exceptpH (units). COliform (organismsllQQ ml), color (units)conductivity (umnos/cm). salinity (0/0')' turbidity (NTU)

Beak Consultants Limited

Laboratoryl385l Shell RoadRichmondlBritish ColumbiaCanadalV6X 2W2Telephone (604) 273·1601Telex 04·508736

REPORT OF ANALYSIS

Client Forestal International limited Project: K4404/38

Date received: 1 October 1979

Number of samples: 1/7

Sample reference

4461

Moisture Content. % 53.9Ash Content (OvenDried). % 0.49

Calorific Value(Wet), BTU/1b 3780

Ca 1ori fi c Value(Oven Dried). BTU/lb 87BO

Organic/InorganicRatio. Wet Basis 0.839

Ref- 4461 - Fi r Tops and Branches

All results expressed as mg/I exceptpH (units). coliform (organisms/l00 mil. color (unitslconductivity (umnoslcm). salinity ('/••l.turbidity (NTUl

65

o

b~ ..:.,~-=

--=

;

'"~

'.-~ ./>.

".-.Typical Processed Material from Bartlett Chipper

Prior to Installation of Chip Breakers

66

Typical Processed Material from Bartlett ChipperAfter Installation of Chip Breakers

67

Typical Processed Material from Nicholson Chipperwith Sharp Knives

68

Large "Card" Chip from Nichol$on Chipper with DuD Knives

69

.~=_o.o=;:

@

••

...:.:., ... .-

©

Comparison of Chip Sizes:

3. Nicholson Chipperb. Bartlett Chipper (Chip Breakers)

c. Bartlett Chipper (No Chip Breakers)

70

Typical Chips from Branch Material

d. Banlen Chipperb. Nicholson Chipper

'"-jJ--:;;

--">I~

'"- ·00';

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,~

·N~

N·W --

"~ -•~

Canadian Forwry ServicePacific Forw Research ~nlfe

506 Ww Bumstdt ROlIdVictoria. B.C. VSZ IM5

BC-X-212. SqMembtr, 1980