doe contract #de-ac22-88pc88881/67531/metadc... · quarterly technical progress report no. 26 for...

QUARTERLY TECHNICAL PROGRESS REPORT NO. 26

FOR PERIOD

JANUARY 1, 1995 THROUGH MARCH 31, 1995

DOE CONTRACT #DE-AC22-88PC88881

I C F KAISER ENGINEERS JOB NO. 88107

"This report was prepared as an account o f work performed by I C F Kaiser Engineers under sponsorship o f the United States Goverrment. Neither the United States nor the United States Department of Energy, ICF Kaiser Engineers, i t s subcontractors, nor any o f t h e i r employees, makes any warranty, express or implied, o r assumes any legal l i a b i l i t y or respons ib i l i t y f o r the accuracy, completeness, or usefulness o f any information, apparatus, product, or process disclosed, or represents that i t s use would not i n f r i nge privately-owned r ights . Reference herein t o any spec i f i c comnercial product, process, or service by trade name, mark, manufacturer, or otherwise, does not necessar i ly const i tu te or imply i t s endorsement, recomrnwlation, or favor ing by the Un i ted States Govertnnent or any agency thereof. The views and opinions of authors expressed herein do not necessar i ly s ta te or r e f l e c t those of the United States Government or any agency thereof."

T C

DISCLAIMER

Portions of this document may be illegible in electronic image products. Images are produced from the best available original document.

TABLE OF CONTENTS

1.0 INTRODUCTION

1.1 Scope o f t h i s Document 1.2 Overa l l P r o j e c t Scope 1.3 Work Executed a t D i f f e r e n t Locat ions

2.0 TASK 2 PRELIMINARY CONCEPTUAL DESIGN

2.1 Overview and Scope 2.2 Review . o f Work Completed Th is Quar te r

3.0 TASK 3 CRITICAL AREA DETERMINATION

3.1 Overview and Scope 3.2 Review o f Work Completed Th is Q u a r t e r

4.0 TASK 4 TEST PLAN FORMULATION

4.1 Overview and Scope 4.2 Review o f Work Completed Th is Quar te r

5.0 TASK 5 BENCH-SCALE PROCESS TESTING

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5.1 Overview and Scope 5.2 Review o f Work Completed Th is Quar te r

6.0 COMPONENT AND UNIT OPERATIONS DEVELOPMENT

6.1 Overview and Scope 6.2 Review o f Work Completed t h i s Quar te r

7.0 EVALUATION OF BENCH-SCALE AND COMPONENT TEST RESULTS

7.1 Overview and Scope 7.2 Work Complete t h i s Quar te r

8.0 REVISED CONCEPTUAL DESIGN OF SEMI-WORKS PLANT


9.0 POC MODULE DESIGN


10.0 POC MODULE FABRICATION

10.1 Overview and Scope 10.2 Review o f Work Completed t h i s Q u a r t e r

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TABLE OF CONTENTS (cont inued)

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11.0 POC INSTALLATION AND START-UP


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12.0 POC TEST PLAN FORMULATION 15


15 15

13.0 POC OPERATION 16


16 16

14.0 POC OPERATIONS ANALYSIS 17


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15.0 FINAL SEMI-WORKS CONCEPTUAL DESIGN 18

15.1 Overview and Scope 15.2 Review o f Work Completed Th is Q u a r t e r

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16.0 POC MODULE REMOVAL 35

16.1 Overview and Scope 16.2 Review o f Work Complete Th is Q u a r t e r

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L I S T OF FIGURES

FIGURE TITLE

1.1 Pro jec t Organization Chart

1.01 S impl i f ied Block Diagram of t h

1.02

POC Process

P i t t sburgh No. 8 Seam Coal, Box-Behnken Matrix Results

1.03 Upper Freeport Seam Coal, Box-Behnken Matrix Results

1.04 I l l i n o i s No. 6 Seam Coal, Box Behnken Matrix Results

1.05 Pi t t sburgh No. 8 Seam Coal Average Performance During 24-Hour Demonstration Run

1.06 Upper Freeport Seam Coal Average Performance During 24-Hour Demonstration Run

1.07 I l l i n o i s No. 6 Seam Coal Average Performance During 24-Hour Demonstration Run

168/DOE/Qt r 1 yRep/Jan-Mar .95 Page iii

TABLE

1.1

1.01

1.02

1.03

1.04

LIST OF TABLES

TITLE

Task and t h e Responsible Team Member

Head Ana lys i s f o r Washabi l i ty Samples

C o n t r i b u t i n s t o Energy Loss and P y r i t i c S u l f u r Removal Dur ing 24-Hour Demonstrat ion Runs

Cap i ta l Requirements and F i r s t Year Operat ing and Maintenance Costs for a 200 TPH Advanced F r o t h F l o t a t i o n P lan t (7560 Hours)

Advanced F r o t h F l o t a t i o n Economics (Annual ized Basis)

168/DOE/PtrlyRep/Jan-Mar.95 Page i v

1 .o INTRODUCTION

A study conducted by Pi t t sburgh Energy Technology Center of sulfur emissions from about 1,300 United S t a t e s coa l - f i r ed u t i l i t y b o i l e r s ind ica ted t h a t ha l f of the emissions were the result of burning coa l s having g r e a t e r t h a n 1.2 pounds of SO, per mi l l i on BTU. T h i s was mainly a t t r i b u t e d t o the high p y r i t i c sulfur content of the b o i l e r fuel. A s i g n i f i c a n t reduct ion i n SO, emissions could be accomplished by removing the p y r i t e from the c o a l s by advanced physical f ine coal c leaning .

An engineering development p r o j e c t was prepared t o bui ld upon the b a s i c research effort conducted under a s o l i c i t a t i o n f o r research i n t o Fine Coal Surface Control. The engineering development p r o j e c t i s intended t o use general p l a n t design knowledge and conceptua l ize a p l a n t t o u t i l i z e advanced f r o t h f l o t a t i o n technology t o process coal and produce a product having maximum p r a c t i c a l p y r i t i c sulfur reduction c o n s i s t e n t with maximum p r a c t i c a l BTU recovery.

1.1 Scope of t h i s Document

The Department of Energy (DOE) awarded a c o n t r a c t e n t i t l e d "Engineering Development of Advanced Physical Fine Coal C1 eani ng Technology - Froth F lo ta t ion" , t o ICF Kaiser Engineers w i t h the following team members, Ohio Coal Development Office, Babcock and Wilcox, Consol i d a t i o n Coal Company, Eimco Process Equipment Company, I11 i n o i s S t a t e Geological Survey, Vi rg in ia Polytechnic I n s t i t u t e and S t a t e Univers i ty , Process Technology, Inc. The organiza t iona l chart f o r this p r o j e c t i s presented i n Figure 1.1.

T h i s document a q u a r t e r l y r epor t prepared i n accordance w i t h the p r o j e c t r epor t ing requirements covering the period from January 1, 1995 t o March 31, 1995. This r e p o r t provides a summary of the technical work undertaken dur ing this period, high1 igh t ing the major results. A b r i e f d e s c r i p t i o n of the work done p r i o r t o this q u a r t e r i s provided i n this r e p o r t under the t a s k headings.

1.2 Overall P ro jec t Scope

The ove ra l l p r o j e c t scope o f the engineering development p r o j e c t i s t o conceptually develop a commerci a1 fl owsheet t o maximize p y r i t i c sul fur reduction a t p r a c t i c a l energy recovery Val ues. Thi s i s being accomplished by u t i l i z i n g the bas i c research d a t a on the surface p r o p e r t i e s of c o a l , mineral matter and p y r i t e obtained from the Coal Surface Control for Advanced Fine Coal F lo t a t ion Project, t o develop this conceptual f lowsheet. The conceptual flowsheet must be examined t o i d e n t i f y c r i t i c a l a r eas t h a t need add i t iona l design d a t a . This d a t a wi l l then be developed using batch and semi- continuous bench s c a l e t e s t i n g . In add i t ion t o ac tua l bench s c a l e t e s t i n g , o t h e r u n i t ope ra t ions from o t h e r i n d u s t r i e s processing f ine materi a1 w i 11 be reviewed f o r po ten t i a1 appl i cat i on and incorporated i n t o the design i f appropr ia te .

The conceptual flowsheet will be rev ised based on the results of the bench s c a l e t e s t i n g and areas will be i d e n t i f i e d t h a t need further l a r g e r s c a l e design d a t a v e r i f i c a t i o n , t o prove out the design. The

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Project Organization Chart

Process Technology Babcock b( Wilcor Ptocerr Dtw&n Procesr &sign

Evaluation €valuation L

Department of Energy

N

I ICF Kaiser Engineers (ICF KE)

Projecf Manager

- ~- -~

ICF KE Project Design

Engineering Project Procurernen# Consfnrcfion Mnmf.

Column Cell Qtimizatirn

I Pmcess Developers Advanced FIofation

Machine

proof-of-concept w i l l be accomplished by designing, cons t ruc t ing , opera t ing and t e s t i n g a 2-3 t o n per hour proof-of-concept p l a n t . Th i s p l a n t w i l l be designed f o r continuous opera t ion and w i l l i nc lude two consecut ive 5 days, 24 hour per day runs on each o f t h e th ree t e s t coa ls t o demonstrate process performance on a commercial bas is .

The da ta from the bas ic research on coal surfaces, bench sca le t e s t i n g and proof-of-concept sca le t e s t i n g w i l l be u t i l i z e d t o des ign a f i n a l conceptual f lowsheet.

The economics o f t h e f lowsheet w i l l be determined t o enable i n d u s t r y t o assess the f e a s i b i l i t y o f i nco rpo ra t i ng t h e advanced f i n e coal c lean ing technology i n t o t h e produc t ion o f c lean coal f o r generat ing e l e c t r i c i t y . Th is concept should p rov ide an a b i l i t y t o reduce s u l f u r ox ide emissions more economical ly than FGD systems when compared on a d o l l a r per t o n o f s u l f u r removed bas is .

1.3 Work Executed a t D i f f e r e n t Locat ions

The p r o j e c t team cons is t s o f research and engineer ing groups a t I C F Ka iser Engineers, Babcock and Wilcox, Consol i d a t i o n Coal Company, Eimco Process Equipment Company, I l l i n o i s S ta te Geological Survey, V i r g i n i a Poly technic I n s t i t u t e and S ta te Un ive rs i t y , Process Technology, Inc. and Michigan Technological U n i v e r s i t y I n s t i t u t e o f M a t e r i a l s Processing w i t h ICF Ka iser Engineers as t h e pr ime con t rac to r w i th DOE. The work be ing conducted by d i f f e r e n t o rgan iza t ions i s based upon t h e i r area o f e x p e r t i s e and t h i s has been incorpora ted i n t o the p r o j e c t Work Plan. The work undertaken by t h e d i f f e r e n t o rgan iza t ions i s i d e n t i f i e d i n Table 1.1. Th is r e p o r t i s prepared i n an i n teg ra ted manner combining work done by each o rgan iza t i on by task. This i s considered t o be a more e f f e c t i v e way o f p resent ing t h e techn ica l da ta developed by each organ iza t ion .

Table 1.1 Task and the Responsible Team Member

Task 1 Task 2 Task 3 Task 4 Task 5 Task 6 Task 7 Task 8 Task 9 Task 10 Task 11 Task 12 Task 13 Task 14 Task 15 Task 16

P r o j e c t P1 anni ng P re l im inary Conceptual Design Determinat ion o f C r i t i c a l Areas Test P1 an Formul a t i on Bench Scale Tes t ing Component Development Ana lys is o f Test Resul ts Revised Conceptual Design POC Module Design POC Procurement and Fabr i ca t i on POC I n s t a l l a t i o n and Star tup POC Test Plan Formulat ion POC Tes t i ng and Operat ion Ana lys is o f POC Test Resul ts F i n a l Conceptual Design POC Module Removal

I C F KE I C F KEY B&W, EIMCO, TSG, TAG I C F KEY B&W, EIMCO, TSG, TAC I C F KEY B&W, EIMCO, TSG I C F KE, B&W, EIMCO, PTI, TSG, TAC V P I , TSG I C F KEY B&W, EIMCO, VPI, TSG I C F KE I C F KEY B&W, EIMCO, TSG, TAC I C F KE I C F KEY B&W, EIMCO, TSG I C F KEY B&W, EIMCO, TSG, TAC ICF KEY B&W, EIMCO, TSG I C F KEY B&W, EIMCO, TSG I C F KEY B&W, EIMCO, TSG I C F KE

168/DOE/PtrlyRep/Jan-Mar.95 Page 3

2.0 TASK 2 PRELIMINARY CONCEPTUAL DESIGN

2.1 Overview and Scope

The previous completion of this task resulted in the preliminary conceptual design of a 20TPH semi-works advanced froth flotation facility. The non-site-specific plant was designed using the best available information and technology to achieve continuous, steady-state process operation with 90% availabil i ty. The process plant is a fully instrumented, integrated, stand-alone facility. A greenfield site was assumed for the plant.

Throughout the project, the work was organized along a tasklsub-task basis with each sub-task 1 ogical ly assigned to provide necessary information for the next sub-task, ultimately resulting in completion of the conceptual design. For Task 2 , the first sub-task determined the design criteria needed to meet or exceed the advanced froth flotation process specifications. At completion, work under this sub-task provided information to design the flowsheet of the process, and provided an energy and material balance of all process streams. A list of all major process equipment was prepared and used as a basis for a factored estimate for the capital, operating and maintenance costs of the semi-works process and plant.

ICF Kaiser Engineers, assisted by the project sub-contractors and Technical Support Group, was responsible for the performance and completion of this task. This conceptual design is the basis for Tasks 3, 4, 5, and 6 and will be revised in Task 8 for use as a basis for the 2-3TPH POC module design in Task 9.

2.2 Review of Work Completed This Quarter

On August 15, 1989, DOE approved Task 1.2 as submitted. With this as a basis, ICF KE and the team members proceeded with the remainder o f the project. No additional work was planned nor completed during this quarter.

168/DOE/Qt r 1 yRep/ Jan-Mar .95 Page 4

3.0 TASK 3 CRITICAL AREA DETERMINATION

3 . 1 Overview and Scope

3.2

Work performed during the concep-ual design of Task 2 identified areas where uncertainties exist in the design o f the unit operations for the advanced froth flotation process. Some of these problem areas could not be solved based on currently available information or technology. The objective of this task was to determine those critical areas where more information would be necessary and out1 ine the work needed to obtain the design information.

A design deficiency list was generated, and the project team determined the parameters needed for final design of the unit operation - either by further engineering analysis or by experimental data obtained from bench-scale tests. Other sol ids processing industries, such as phosphate and clay beneficiation, were examined to assess the means by which they effectively process ultra fine particles.

Each identified design deficiency was then ranked according to its relative importance to the successful continuous operation of the advanced froth flotation process. Both a technical and economic analyses of the consequences of not being able to gather the required design information for each deficiency was evaluated.

ICF Kaiser Engineers, Consolidation Coal and the other members of the Technical Support Team (B&W, VPI and EIMCO) have contributed to this task. The process deficiencies identified in this task will be addressed in Tasks 4, 5, and 6 through additional engineering computation and analysis and experimental techniques.

Review o f Work Completed This Quarter

The final report of this task has been submitted to DOE. No additional work was planned nor completed during this quarter.

168/DOE/Q t r 1 )'Rep/ Jan-Mar -95 Page 5

4.0 TASK 4 TEST PLAN FORMULATION

4 . 1 Overview and Scope

Work completed in this task produced the criteria for additional engineering analysis, computation and detailed experimental bench- scale testing for areas of uncertainty identified in Task 3 . The engineering analysis, computation, bench-scale testing and component development was formulated to produce necessary design information to define a commercially operating system.

In order to produce the required information by means of bench-scale testing and component development, a uniform coal sample was procured. After agreement with DOE, a selected sample of coal from those previously listed was secured.

The test plan was developed in two parts. The first part listed procedures for engineering and computational analyses of those deficiencies previously identified that could be solved without bench scale testing. Likewise, the second part prepared procedures for bench-scale testing and component development for those deficiencies previously identified in Task 3 .

The first part, engineering analysis and computation, provided for means of employing presently know theory from other industries to address deficiencies. This included examinations o f 1 iterature and contacting proven experts and operating personnel in fields related t o this deficiency. From the information gathered, engineering calculations will be utilized to resolve this type of deficiency.

The second part, bench-scal e testing and component devel opment, became necessary when the part one information was unavailable or when the theory had never been commercially applied. Justification for the test work was provided to show that technical data and process needs could only be obtained by test work and that the test work results would produce necessary information to define a commercially operating system.

The test work planned was based upon non-continuous and/or semi- continuous bench-scale units of general 1 aboratory design and would include only those unit operations identified as deficiencies in Task 3 .

The detailed, quantified tests addressed obtaining data necessary for solving problems uncovered in the deficiency review. Each identified deficiency had a plan developed to address the reason for the testing, the means for the test matrix to obtain results and the expected results. Each test plan established procedures, adhering as much as possible, to known and industry-acceptable procedures for sampling and data collection. Raw data collection would be reduced to minimize expenses and to better be able to compare results and obtain meaningful information, especially scale-up factors.

168/DOE/Ptr lyRep/Jan-Mar .95 Page 6

The Development Test Plan for both p a r t s one and two contained schedules, manpower requirements, and resources necessary t o obtain information t o def ine a commercially ava i lab le system.

The plan f o r use of t he team members was developed t o comply with the results of the DOE uniform coal sample procurement and s torage procedures. The quant i ty of coal necessary f o r each t e s t i n g program was ca lcu la ted . A sample of a l l t h ree of t h e referenced coa ls was t o be obtained, preferably from t h e same source a s the Surface Control cont rac tor . This coal would be stored and handled as out l ined in the coal procurement and s torage plan. These procedures, when properly followed, should minimize physical and chemical changes t o the raw coal .

4 . 2 Review of Work Completed This Quar t e r

The Task 4 Report was submitted t o DOE as a f i n a l repor t . No addi t ional work was planned nor completed during t h i s quar te r .

168/DOE/Pt r 1 yRep/ Jan-Mar .95 Page 7

5.0 TASK 5 BENCH-SCALE PROCESS TESTING


The overa l l goal of Task 5, "Bench-Scale Process Testing" i s t o develop the necessary u n i t opera t ion design and process performance d a t a requi red t o 1) reduce o r eliminate the technica l and engi neeri ng uncer ta i n t i es of the pre l imi nary 20TPH advanced 1 oca t i on semi-works p l a n t and 2) design, bu i ld and opera te a 2-3 TPH advanced f l o t a t i o n POC module.

The u n i t opera t ion performance and process design information requi red t o support development of the advanced f l o t a t i o n process is being examined i n a m u l t i - t i e r program a t B&W and Process Technology, Inc. Laboratory s c a l e s t u d i e s a r e being conducted i n severa l key process a reas - conventional precleaning of the raw coa l , m i c rogr i ndi ng of the pre-cl eaned coa l , advanced f r o t h f l o t a t i o n of the f ine coal and dewatering of the product streams. The results of these s t u d i e s are then being used t o guide small , semi-continuous and continuous t e s t i n g of the key u n i t opera t ions a t approximately 100 1 b/hr.

The bench-scale and semi-continuous process design eva lua t ion test programs will provide d e t a i l e d information f o r developing process mater ia l and energy balances. The mater ia l balance da t a wi l l be used t o c o r r e c t l y design and s i z e the equipment f o r the POC module. The energy balance information will allow f o r es t imat ion the c o s t effectiveness of the design.

The bench-scale tes t programs will a l s o i d e n t i f y the optimum condi t ions f o r microgrinding the coal f o r maximum p y r i t i c sulfur r e j e c t i o n i n advanced f l o t a t i o n and the most promising advanced f l o t a t i o n technique which will then be in t eg ra t ed i n t o the overa l l processing scheme. The 100 l b / h r t es t program wi l l provide v e r i f i c a t i o n of the l abora to ry tests results and demonstration t h a t these results can be scaled-up f o r app l i ca t ion i n the 20TPH semi- works p l an t design.

Both the bench-scale, semi-continuous and continuous process design eva lua t ion tes ts will se rve a s c r i t i c a l reviews of the preliminary process flowsheet. Process d e f i c i e n c i e s and l i m i t a t i o n s discovered i n these programs wi l l r equ i r e modification of the o r ig ina l conceptual f lowsheet. This information will a i d i n i den t i fy ing s o l u t i o n s t o the successful implementation of advanced f l o t a t i o n technology.

The bench-scale and process t e s t i n g c o n s i s t s o f eleven major subtasks performed over a period of 12 months.

5.2 Review of Work Completed T h i s Q u a r t e r

T h i s t a s k has been completed and the results o f t h repor ted i n the Task 7 r epor t . No addi t iona l work was completed during this qua r t e r .

s t a s k a r e planned nor

168/DOE/Qt r 1 yRep/Jan-Mar .95 Page 8

6.0 COMPONENT AND UNIT OPERATIONS DEVELOPMENT


The Task 6 effort involves three main elements including column cell development, flotation circuit testing and flotation cell modeling. The work outlined is to research column designs and operation parameters in developing an optimized column flotation cell (OCFC) to meet the overall program objectives. The test results obtained through this effort will be evaluated against the results obtained from the round-robin test program in Task 5. Any design parameters or operating conditions that are unique with the round-robin test winner that were not evaluated as part of the optimized column development work will be reviewed and tested so as to incorporate all possible scenarios in presenting DOE with the best available flotation process for use in the 2 to 3 ton per hour POC.

Following development of the OCFC, various flotation circuit configurations will be evaluated determine the "best" circuit design for the 2 to 3 ton per hour POC. Single and multiple stage flotation, grab and run, rougher/scavenger/cleaner, etc., test circuits will be tested as part of this effort. Upon completion of this test work, the "best" possible flotation cell will have been tested in a number of possible flotation circuit designs to possibly provide the "best" flotation approach in meeting the design cri teri a.

In conjunction with the flotation test effort, model development work will be conducted to provide a tool in evaluating the various flotation circuit configurations and in predicting flotation performance. The model will be useful in selecting operating conditions in the POC and in evaluating the performance of the POC.

6.2 Review of Work Completed this Quarter

This task has been completed and the results of this task are reported in the Task 7 Report. No additional work was planned or completed during this quarter.

168/DOE/Pt r 1 yRep/Jan-Mar .95 Page 9

7.0 EVALUATION OF BENCH-SCALE AND COMPONENT TEST RESULTS


A bench-scale and component testing report was prepared and submitted to DOE after completing Task 5 and Task 6.

The report included the preparation, presentation and analysis of all the experimental data obtained in the bench-scale and component unit operations, development and testing. A comparison of the results obtained with the expected limitations and deficiencies that occurred from bench-scale testing was compiled.

Following the evaluation of the bench-scale and component testing results, a residual needs analysis was prepared. This was prepared after comparing results learned in Tasks 5 and 6 with the original residual needs analysis.

Finally, a bench-scale testing summary was prepared. It specifically addressed the results of the bench-scale component testing in respect to the information necessary to define a commercially operating system. This included equipment selection, sizing, evaluation and operation to achieve both coal cleaning as well as the cost of system operation.


This task has been completed and the Task 7 Report submitted to DOE in its final version. No additional work was planned or completed during this quarter.

168/DOE/Qtr lyRep/Jan-Mar -95 Page 10

8.0 REVISED CONCEPTUAL DESIGN OF SEMI-WORKS PLANT


Following DOE authorization to proceed with this task, the preliminary conceptual design of a 20TPH semi-works plant (Task 2) was redesigned from all information available at this point in the project. This update of the conceptual design incorporated information derived about fine grinding, advanced froth flotation, and dewatering in Tasks 5 and 6. The summary report produced in Task 7 describing bench-scal e test results and component development was used as a basis.

This task complied with all of the design requirements discussed in Task 2. The process flowsheet was updated with complete energy and material balances for all process flowstreams. The equipment list was updated and supplied the base for a recalculation of the factored estimate of the capital, operating and maintenance costs. In addition, differences between the designs in Task 8 and Task 2 was highlighted and their effects on process and plant design credibility, efficiency, maintenance, operation, complexity, control , performance, and economics were discussed. ICF Kaiser Engineers, with assistance from its sub-contractors and the Technical Support Group, were responsible for the completion of this task. This design will serve as a basis for the POC design in Task 9 and the final semi-works design in Task 15.


This task has been completed and a final report submitted to DOE. No additional work was planned or completed during this quarter.

168/DOE/Q t r 1 yRep/ J an-Mar .95 Page 11

9.0 POC MODULE DESIGN

9.1

9.2

Overview and Scope

In order to develop additional confidence in the conceptual design of the advanced froth flotation circuit, a 2-3 TPH Proof-of-Concept (POC) facility was necessary. During operation of this facility, the ICF KE team will demonstrate the ability of the conceptual flowsheets to meet the program goals of maximum pyritic sulfur reduction coupled with maximum energy recovery on three DOE specified coals. The POC circuit was designed to be integrated into the Ohio Coal Development’s facility near Beverly, Ohio.

OCDO’s facility will provide the precleaning unit operations and ICF KE will add the advanced froth flotation circuitry. The work in this task will include the POC conceptual design, flowsheet development, equipment list, fabrication and construction drawings, procurement specifications and bid packages and a facilities estimate at the completion of design. After DOE approval, the design was finalized for the next task.

Review of Work Completed this Quarter

This task has been completed and the Task 9 report submitted to DOE. No additional work was planned or completed during this quarter.

1 W D O E / P t r 1 yRep/Jan-Mar -95 Page 12

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10.0 POC MODULE FABRICATION


The overall objective of this task is to obtain the equipment, materials and shop labor to fabricate and assemble each of the individual modules which constitute the POC Module. The ICF KE procurement team will solicit bids, place orders, and expedite all vendors, materialmen and fabricators. Procurement will uti1 ize the drawings and specifications produced in Task 1.9 as the basis for these activities. At the completion o f the assembly procedure, a ICF KE representative will inspect and perform a functional check o f each module before it leaves the shop.

Several sub-tasks have been identified for their importance in the successful completion of this task. Work will include placing purchase orders, procurement o f the equipment and materials, fabrication of the modules, functionally checking the modules, shipping the modules to the jobsite and preparing the installation and maintenance manual s.

10.2 Review o f Work Completed this Quarter

This task has been completed. No additional work was planned or compl eted during this quarter.

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11 . O POC INSTALLATION AND START-UP


This task covers the functions necessary to install and successfully start-up the POC module at the jobsite. The installation was carried out by an installation subcontractor with construction management provided by ICF KE. The start-up was supervised by ICF KE and conducted using process engineers from the entire team and craft labor supplied by the installation subcontractor.

This task includes several major subtasks which was carried out to assure a successful , on-schedule installation and start-up. ICF KE will conduct work on installation and interconnection of the modules, preparation of start-up plans and procedures, the start-up functions and the finalization of the operations manual.

DOE’S TPO was kept informed o f construction progress and has access to the site for inspection of the work. ICF KE’s construction manager was assigned prior to the start of construction activities and maintained the job progress through on-site assessment o f the work and was using the construction schedule produced in Task 9 for control.


All construction has been completed. No additional work was planned or completed during this quarter.

168/DOE/QtrlyRep/Jan-Mar.95 Page 14

I

12.0 POC TEST PLAN FORMULATION


The project team will coordinate its expertise and develop a testing plan that will provide performance data, quality data, scale-up data and operating data. The plan was submitted to DOE for approval after completion of Tasks 9 and 10.

This plan, after approval/revisions, will become the final test plan. The test plan will include long term testing, steady-state operation and effects of recycle operation. The testing program wi 11 demonstrate 90% onstream capabi 1 i ty, eval uate process control instrumentation, develop information for scale-up, demonstrate compl i ance with regul atory requirements, eval uate materi a1 s o f construction , and determi ne process economics . Anci 11 ary information such as qual i ty of waste stream materi a1 s was gathered.

The finalized plan will include a budget and schedule t o complete all required tests and to produce batches of material for testing of beneficiated coal .


This Task has been completed. No additional work was planned or completed during thi s quarter.

1 68/DOE/Q t r 1 yR ep/ J an- Ma r .95 Page 15

13.0 POC OPERATION


This task i s the actual demonstration of the advanced froth f lotat ion technology. All previous work has led t o t h i s t a sk . ICF KE technicians and process engineers from the team will operate the p l a n t over a 10 month period t o demonstrate the capabili ty of the technology t o remove 85% of the pyr i t ic sulfur from three different t e s t coals while covering a t l eas t 85% of the as-mined coal ' s energy content.

S i x major subtasks have been included t o bet ter define the overall work scope for t h i s task. The ICF KE team will t e s t the Pittsburgh #8 seam, the I l l i no i s #6 seam and the Upper Freeport seam; the team will operate the c i r cu i t in a continuous r u n ; the team will analyze a l l samples generated i n those runs and will develop a plan t o store and dispose of the coal and refuse products.

A1 1 1 aboratory data generated wi 11 be accessible t o a1 1 team members and the DOE. The TPO will be notified of a l l r u n days in advance for the purpose of planning his trips t o the s i t e . Sufficient time will be allowed in the t e s t plan, developed in Task 12, t o permit quick analysis of data generated from a completed t e s t before continuing t o the next t e s t .


This Task has been completed. No additional work was planned o r compl eted during t h i s quarter.

168/DOE/Qt r 1 yRep/ Jan-Mar .95 Page 16

14.0 TASK 14 POC OPERATIONS ANALYSIS


The completion of this task will result i n a complete ana lys i s of the results from a l l t h e test runs on a l l o f the c o a l s cleaned i n the POC module. The work wi l l include, i n an organized and r e a d i l y accessi bl e manner , a1 1 avai 1 ab1 e 1 aboratory d a t a and opera t ing results from the Advanced F lo ta t ion technology. The information will be u t i l i z e d t o genera te results t h a t will be compared t o the batch and semi-continuous results with respect t o q u a l i t y and equipment design parameters. T h i s information will then be used f o r the Final Conceptual Design of the 20 TPH semi-works f a c i l i t y . The results will be contained i n a formal POC Tes t ing Summary Report.

14.2 Review of Work Completed T h i s Quarter

This Task has been completed. No addi t iona l work was planned o r completed during this q u a r t e r .

168/DOE/Qtr lyRep/ Jan-Mar .95 Page 17

15.0 TASK 15 FINAL SEMI-WORKS CONCEPTUAL DESIGN


A t the completion of t h i s task, a conceptual design for a 20 TPH semi-works f a c i l i t y will be available. The design will based on a l l knowledge gained previously in Tasks 5, 6 , and 13. The work in t h i s task will be primarily concerned with updating the conceptual design tha t was available in Task 8 with resu l t s of the POC scale-up operations from Task 13. Further, the team will project the design t o a 200 TPH commercial f a c i l i t y and provide a conceptual estimate of the capital and operating costs for t h a t f a c i l i t y .

The task will include several deliverables - the final report , design drawings for the semi-works plant, a detailed capital cost estimate of the semi-works plant and a preliminary conceptual estimate for the commerci a1 plant.


The following i s the executive summary of the Final Report. For additional information, please see the Final Report.

Bench-Scal e Test Results

Bench-scale tes t ing was conducted in order t o reduce the technical and engineering re1 ated design deficiencies of the proposed advanced froth f lotat ion process. For bench-scale tes t ing , the coarse fraction (1/4 in. x 48 mesh) of the Pittsburgh No. 8 seam coal was precleaned in a water-only cyclone while the Upper Freeport and I l l i no i s No. 6 coals were precleaned in a heavy-media cyclone. The heavy-media cyclone achieved energy recoveries of 95 percent or greater while the water-only cyclone performance was poor, with an energy recovery of only 85 percent.

The clean coal from the coarse gravity-based cleaning c i rcu i t was then crushed to 48 mesh x zero and, in the case of heavy-media cyclone cleaning, combined with the natural 48 mesh x zero s ize f ract ions of the raw coal. The coarse water-only cyclone clean coal already contained the 48 mesh x zero material. The result ing 48 mesh x zero streams fo r a l l three coals were then cleaned in a water-only cyclone. For each coal , water-only cyclone energy recoveries were greater than 95 percent. Pyrite rejections were 28 percent and 31 percent for the Pittsburgh No. 8 and Upper Freeport coal seams, b u t only 13 percent for the I l l i no i s No. 6 coal seam.

The clean coal from the water-only cyclone operation was classif ied into 48 mesh x 200 mesh and 200 mesh x zero size fractions for conventional froth f lotat ion tes t ing. Investigators evaluated "grab-and-run" f lotat ion in an e f fo r t t o produce a clean coal from the f lotat ion "grab" stage of s ix percent ash or l e s s for a l l three coals. The Upper Freeport "grab'l product met the clean coal ash target while the I l l i no i s No. 6 seam coal "grab" product c lear ly did not meet the s ix percent ash c r i t e r i a . No firm conclusions were

168/DOE/Qt r t yRep/ J an- Ma r -95 Page 18

reached regarding the "grab" product for the Pittsburgh No. 8 seam coal a s the "grab" product ash s l igh t ly exceeded s ix percent.

Grinding c i r cu i t evaluations conducted for t h i s project included the comparison of the cleaning performance potential a t two different coal grinds, 200 mesh and 325 mesh, using the Pittsburgh No. 8 seam coal. Each of these samples were then cleaned in a 2-inch diameter column f lotat ion cell in order t o compare the separation character is t ics of the two coal grinds. The resul ts from the column t e s t s indicated t h a t the 325 mesh x zero s ize fraction l ibera tes significantly more pyrite than the 200 mesh x zero grind. A t roughly identical energy recoveries of nearly 96 percent, 36 percent of the pyrite was rejected with the 325 mesh grind while only 25 percent was rejected with the 200 mesh grind.

Column f lotat ion tes t ing a t the bench-scale level included extensive tes t ing in a labora tory s ize column f lotat ion unit followed by 100 pounds-per-hour tes t ing in larger units. A t the labora tory level, investigators evaluated whether multiple-stage column f lotat ion could significantly outperform single-stage column f lotat ion. In addition, a 54-point t e s t matrix was developed using a composite Box-Behnken design and conducted on single-stage column f lotat ion. All da t a obtained during the single versus multiple-stage f lotat ion tes t ing form a re1 at ively narrow band of potential grade-versus- recovery resul ts . Therefore, investigators ruled ou t a mu1 t ip le - stage approach for POC operations. The da ta from the 54 point t e s t matrix indicate t h a t the best resu l t s between energy recovery and pyrite rejection occurred between 55 and 63 percent pyrite rejection with energy recoveries of up t o 92 percent.

Using the best resul ts from the 100 pounds-per-hour tes t ing of each u n i t operati on and B i lmat , a computer-based materi a1 bal ance program, investigators next devel oped overall cleaning c i r cu i t performance projections in order t o assess the potential for meeting the major coal cleaning performance goals. For the Pittsburgh No. 8 seam coal, neither the energy recovery nor the pyritic-sulfur- rejection target of 85 percent was achieved, primarily due t o the poor coarse water-only cyclone performance. The I l l i no i s No. 6 seam coal projection indicated a 91 percent pyr i t ic sulfur rejection with a nearly 81 percent energy recovery. For the Upper Freeport seam coal, the projections indicated 78 percent pyrite rejection and 91 percent energy recovery were possible.

Clean coal and refuse s lu r r i e s were subjected t o dewatering t e s t s using pressure f i l t r a t i o n , vacuum f i l t r a t i o n , and belt f i l t e r press techniques. The target moisture for the clean coal was 30 percent while the refuse moisture target was 35 percent. The bench-scale dewatering t e s t resu l t s indicated that the clean-coal-moisture goal could be achieved with the Pittsburgh No. 8 and Upper Freeport seam coals using pressure f i l t r a t i o n techniques. The I l l i no i s No. 6 seam coal could only be dewatered t o 38 percent moisture. Neither the vacuum f i l t r a t i o n techniques nor the belt f i l t e r press could produce 30 percent clean coal moistures for any o f the three coals.

168/DOE/Qt r LyRep/ Jan-Mar .95 Page 19

Tests on the refuse samples of each coal indicated tha t the fine Upper Freeport seam refuse could be dewatered t o less than 35 percent moisture using vacuum f i l t r a t i o n , pressure f i l t r a t i o n , or the bel t f i l t e r press. Only vacuum f i l t r a t i o n could meet the 35 percent target on the I l l i no i s No. 6 refuse, and only pressure f i l t r a t i o n was successful on the Pittsburgh No. 8 seam refuse. Despite the lack of success of the bel t f i l t e r press on these two coals, the bel t f i l t e r press was recommended for dewatering the refuse stream for a l l three coals, primarily due t o the superior handleability of the bel t press refuse cake.

Based on the bench-scale and 100 pounds-per-hour test resu l t s , the following conclusions were drawn for the Semi-works flowsheet:

e The coarse water-only cyclone (1/4 inch x 48 mesh) continued t o be included in the plant design. However, a heavy-media cyclone would be used in the POC and, i f successful, be considered for the final Semi-Works plant design.

0 The f ine (48 mesh x zero) water-only cyclone c i rcu i t was maintained in the Semi-works plant design.

the 48 mesh by 200 mesh and the 200 mesh x zero size fractions.

e Conventional froth f lotat ion should be applied separately on

0 The raw coal crusher, the precleaned o r middlings coal crusher, and ball-mill were t o be sized by the equipment manufacturers based on the maximum par t ic le size, the Hardgrove grindabili ty of the feed, the t o p s ize requirements for the crushed products, and the throughput tonnage.

e A multiple-stage column f lotat ion c i r cu i t was n o t warranted due t o the relat ively s l igh t improvement in grade-versus- recovery resul ts when compared t o sing1 e-stage column f lotat ion resul ts .

0 A clean-coal thickener would need t o be included in the design t o concentrate the advanced froth f lotat ion concentrate.

e A batch-type recessed plate pressure f i l t e r would achieve the lowest clean-coal-product moisture. However, a final decision regarding the dewatering of clean coal for the Semi-works plant design will occur a f t e r POC testing i s completed on a hyperbaric disk f i l t e r .

0 Dewatering of the refuse thickener underflow will be accompl i shed using a bel t - f i 1 t e r press.

Proof-Of-Concept (POC) Scale Test Results

Figure 1.01 presents a simplified block diagram of the POC f l owsheet.

168lDOElQtr lyRep/Jan-Mar .95 Page 20

114" x 48 mesh

114" x 48 mesh Refuse

48 me #h x 0

I

114" x 0 Refuse

114" x 48 mesh Clean Coal

200 mesh x 0 Refuse

-

114" x 48 mesh Clean Coal

Cagepactor Crusher

48 mesh x 0 i Hydrocycl one

I

48 mesh x 0 Ref use

48 mesh x 0 Clean Coal

Col umn F lo ta t i on

200 mesh x 0 Clean Coal I

Figure 1.01 Simplified Block Diagram of the POC Process


As can be seen from Figure 1.01, the 1/4 inch x 48 mesh was cleaned using a heavy-media cyclone with the objectives of recovering 97 percent of the feed coal ' s energy. The heavy-medi a-cycl one cl ean coal was crushed to 48 mesh by zero using a cagepactor crusher, combined with the raw 48 mesh by zero and fed to a water-only cyclone. The water-only cyclone was maximized to recover 97 percent of its feed energy. The water-only cyclone clean coal reported to the ball-mill where it was crushed to 200 mesh by zero and fed to the column flotation cell for final cleaning. Primary performance goals of the POC flowsheet were to achieve 85 percent energy recovery with 85 percent pyritic sulfur removal when compared to the raw coal feed of the plant.

The Pittsburgh No. 8 seam coal from Brooke County, West Virginia; the Upper Freeport seam coal from Somerset County, Pennsylvania; and the Illinois No. 6 seam coal from Salone County, Illinois were the three coals tested. Table 1.01 contains the washability head analyses on a dry basis for the three coals.

i ~

Coal Seam

Pi t tsburgh No. 8

Upper Freeport

I l l i n o i s No. 6

% Ash % Sulfur % P y r i t i c Sulfur Btu/l b

40.38 3.14 2.16 8,292

18.12 3.99 2.81 11,975

36.23 4.11 2.75 8.866

Once the heavy-media cyclone, water-only cyclone, and grinding circuits were maximized, testing began to determine the best conditions at which to operate the advanced column flotation cell. The critical operating variables that were evaluated for the column cell included feed rate, aeration rate, frother rate, wash-water rate, frother type, and collector rate. A 16 point, resolution IV fractional factorial experiment was conducted on the Pittsburgh No. 8 seam coal to determine the best conditions for aeration rate, wash-water rate and frother type for the column cell. Results from the fractional matrix testing concluded that the following parameters should remain constant for the column cell throughout the remai nder of the POC operat i ons . 0 MIBC reagent should be used as the frothing agent.

e An aeration rate of 140 SCFM should be maintained.

e A wash-water rate of 100 gallons per minute should be maintained.

With the heavy-media cyclone and water-only cyclone maximized, and with the best conditions for aeration rate, wash-water rate, and frother type determined for the column flotation cell, investigators conducted a Box-Behnken test matrix on each of the three coals. Figures 1.02, 1.03, and 1.04 show the energy recoveries as a

Page 22 168/DOE/P t r 1 yRep/ Jan-Mar -95

funct ion of ash r e j e c t i o n , p y r i t i c s u l f u r r e j e c t i o n , and t o t a l s u l f u r r e j ec t ion for the overal l POC c i r c u i t while conducting the Box-Behnken t e s t matrices f o r t h e Pi t tsburgh No. 8, Upper Freeport , and I l l i n o i s No. 6 coal seams.

PITTSBURGH NO. 8 COAL COLUMN FLOTATION PERFOMNCE

t s

After completing the Box-Behnken matrix for each of t h e th ree coa l s , a l l equipment was configured and a l l va r i ab le s were set a t the maximum values t o conduct t he 24-hour demonstration t e s t s . The Pi t tsburgh No. 8 seam was processed for four days during the f i r s t and second week o f t he demonstration r u n . Both the Upper Freeport and I l l i n o i s No. 6 seams were processed f o r f i v e days during both t h e f i r s t and second week of t h e demonstration runs. During the 24- hour demonstration runs, a complete s e t o f samples were co l lec ted every e igh t hours f o r a l l the pe r t inen t c i r c u i t s in operat ion. Figure 1.05, 1.06, and 1.07 present the Bilmat-adjusted da ta for the average of a l l eight-hour sampl ing periods f o r the Pi t tsburgh No. 8, Upper Freeport , and I l l i n o i s No. 6 coal seams.

For t h e Pi t tsburgh No. 8 Seam, t h e POC recovered 89.5 percent of t he raw coa l ’ s energy while removing 73.6 percent of the coa l ’s p y r i t i c s u l f u r . Performance evaluat ions for t h e Upper Freeport Seam indicated an overal l energy recovery of 87.5 percent , while 76.2 percent of t he raw coa l ’s p y r i t i c s u l f u r was removed. For the Upper Freeport Seam, the POC recovered 85.8 percent of t he energy and removed 79.4 percent of t h e p y r i t i c s u l f u r in t h e raw coa l .

Table 1.02 presents t h e cont r ibu t ions of each coal-cleaning c i r c u i t t o t o t a l energy loss and py r i t i c - su l fu r removal for each of the

168/DOE/Pt r 1 yRep/Jan-Mar .95 Page 23

UPPER FREEWRT COAL COLUMN FLOTATION PERFORMANCE

30 40 sa 70 80 00 100 110

ENERGY RECOVERY Cm m ASH 0 SULFUR x PYRITIC SULFUR

Figure 1.03 Upper Freeport Seam Coal, Box-Behnken Matrix Results

t h r e e coa ls . These values a re based on the average results obtained during t h e 24-hour demonstration runs. The heavy-media cyclone c i r c u i t f o r each coal removed the bulk of t h e p y r i t i c s u l f u r while los ing r e l a t i v e l y l o w amounts of energy. Depending on the coa l , the heavy-media cyclone c i r c u i t removed 60 t o 70 percent o f t he t o t a l amount of p y r i t e t h a t was removed. Meanwhile, t he energy content in t h e heavy-media cyclone c i r c u i t re fuse was only 32 t o 36 percent o f t h e t o t a l energy lo s ses .

Since l a rge amounts of p y r i t e have been removed p r i o r t o the water- only cyclone and the advanced f r o t h f l o t a t i o n c i r c u i t , t he r a t i o of p y r i t e r e j ec t ion t o energy loss i s s i g n i f i c a n t l y lower for these c i r c u i t s . For t h e Upper Freeport Seam, f o r example, the advanced f r o t h f l o t a t i o n removed 25 percent of t he t o t a l amount of p y r i t e t h a t was r e j ec t ed , and t h e energy content in t h e f l o t a t i o n t a i l i n g s accounted for 71 percent of t h e t o t a l energy lo s ses . Contributing t o t h e lower r a t i o s i s the more-difficult-to-clean nature of f ine- and ul t r a f i ne-parti c l e streams.


I L L I N O I S NO. 6 COAL COLUMN F L O T A T I O N PERFORMANCE 90

eo

70

60

50

40

20

O ooo"o 3

10

Pit tsburgh No. 8 Coal Upper Freeport Coal

C1 eaned) Energy Pyr i t e Energy P y r i t e Loss R emo va 1 Loss Removal

C i rcu i t (Size

Heavy-Medi a 3.8 44.3 2.7 49.4 Cyclone

C i rcu i t (+48 mesh)

Water-On1 y Cyclone 4.0 16.6 0.9 7.9 Circu i t (48 mesh x 0)

Advanced Froth 2 .7 12.7 8.9 18.9 F1 o t a t i on Ci rcui t (200 mesh x 0)

73 80 85 90 3s 1 D D

ENERGY RECOVERY C%] m ASH 0 SULFUR x PYRIT IC SULFUR

Figure 1.04 Illinois No. 6 Seam Coal, Box-Behnken Test Matrix Results

I l l i n o i s No. 6 Coal

Energy Pyr i t e Loss Removal

4.5 55.. 4

2 . 2 10.4

7.5 13.6

Cumulative plant availability during 24-hour demonstration runs for the three coals was 94.9 percent. Indi vi dual 1 y , pl ant availabilities for the Pittsburgh No. 8, the Upper Freeport and the Illinois No. 6 coals were 98.0, 97.4, and 89.9 percent, respectively. No downtime encountered during the demonstration runs was attributed to the advanced process equipment.


Figure 1.05 Pittsburgh No. 8 Seam Coal

Average Performance During 24-Hour Demonstration Run Plant Feed I Ash % 46.05

Totalsulfur % 2.90 Pyritic Sulfur % 2.04 BTU Per Pound 7,329 L Coarse circuit perfomnce

96.2% Energy Recovery ' 44.3% Pyrite Rejection I \

Fine Circuit Performance 95.9% Energy Recovery 29.8% Pyrite Rejection

1 Pyrite I

Mill Product 85.4% Passing 200M Mesh 38.4 Micron Average Particle Size 23.4 Micron 050

Plant Clean Coal % of Raw Coal Ash % Weight 48.2 Total Sulfur % 2.50

Pyrite 26.4 BTU Per Pound 13,618 Energy 89.5 PyriticSulfur % 1.12

Plant Refuse Ash % % of Raw Coal

Weight 51.8 Total Sulfur % 3.27 Energy 10.5 PyriticSuffur % 2.90 Pyrite 73.6 BTU Per Pound 1,479

Plant Feed Ash % Total Sulfur %

BTU Per Pound 11,048 Pyritic Suifur %

Advanc

f

Figure 1.06 Upper Freeport Seam Coal

Average Performance During 24- Hour Demonstration

Coarse Circuit Performance 97.3% Energy Recovery 49.4% Pyrite Rejection

1/4" x 48M

r Coarse Refuse i

I

Run

Plant Clean Coal Ash % % of Raw Coal

Weight 71.9 Total Sulfur % 2.30 Energy 87.5 Pyritic Sulfur % 1.06 Pyrite 23.8 BTU Per Pound 13,456

PlantRefuse % of Raw Coal Ash % 59.63 Weight 28.1 Total Suffur % 9.80 Energy 12.5 PyriticSulfur % 8.66 Pyrite 76.2 BTU Per Pound 4,902

eunsg615rl

Figure 7.07 lllinois No. 6 Seam Coal Average Performance

r Plant Feed During 24-ff our Demonstration Run Ash % Total Sulfur % Pyritic Sultirr % BTU Per Pound L Coarse Circuit Performance

7 95.5% Enetgy Recovery 55.4% Pyrite Rejection

Fine Circuit Performance 97.7% Energy Recovery 23.3% Pyrite Rejection

LL

f Advanced Flotation Performance

92% Energy Recovery 39.6% Pyrite Rejection

28.3 Micron 050

r ~ CoarseRefuse i % of Raw Coal

Weight Energy

rite

4 8 M x O

2.2 I 10.4 r

Mill Product % Passing 200M 83.9% Passing Mesh 42.3 Micron Average Particle Size

Ultra fine Refuse % of Raw Coal

Weight

13.6

Energy 85.8 pVriticSulfur % 0.86 20.6 BTU Per Pound 13,574

72.08

Energy 14.2 Pyritic Sulfur % 4.55 79.4 BTU Per Pound 3,084

Conceptual Design for 20 TPH Semi-works Plant

The bench-scale and POC-scale test plans were designed to provide investigators with the information necessary to design and engineer a 20 tons-per-hour Semi-works Facility that incorporates the proposed advanced froth flotation technology and achieves the objectives established for the process. The coal cleaning philosophy that was applied to the project was twofold: first, to remove sulfur and mineral matter at the coarsest size consistent with low subsequent energy losses; and to utilize multiple coal communition stages to liberate mineral matter and impurities from the desirable coal portion of the raw coal feed stream.

To accomplish this and to meet project goals, the Semi-works facility includes three stages of coal crushing and grinding operations each followed by a cleaning operation designed to remove the liberated impurities generated by the communition efforts. Raw coal received at the facility will be crushed to 1 / 2 inch by zero. The crushed product is separated into two sizes and the 1 /2 inch by 48 mesh size fraction i s efficiently cleaned in a heavy-media cycl one ci rcui t . The heavy-medi a cyclone wi 11 be configured to effect a high (1.85 to 1.90 S.G.) specific gravity of separation on the coal feed so that little energy is lost.

The heavy-media cyclone clean coal is crushed, in closed circuit, to 48 mesh by zero, combined with the raw 48 mesh by zero size fraction and cleaned in a water-only cyclone circuit to remove impurities liberated by the crushing stage or present in the raw fraction. Again, the water-only cyclone circuit is configured to minimize energy losses, yet remove both pyritic sulfur and mineral matter prior to fine grinding.

The heavy-media- and water-only-cyclone circuits represent commerci a1 ly proven and avai 1 ab1 e technol ogi es that are practical and effective for their intended use in the process. Significant pyritic sulfur rejections at low energy loss can be expected at this point in the process. The material removed from these operations would be, for many coals, the hardest materials and the most expensive to grind on a per-pound basis.

The water-only cyclone clean coal is introduced into a closed, wet- grinding circuit utilizing classification ahead o f a horizontal ball mill to prepare a proper ball-mill feed and improve circuit effectiveness. The mill circuit will produce a product of approximately 83 to 85 percent passing 200 mesh that will finally be cleaned in the advanced froth flotation circuit. Thickening, dewatering, and recovery techniques for all circuit products will use commerci a1 ly avai 1 ab1 e technol ogi es.

The Semi-works facility will be a fully automated continuous process. State-of-the-art instrumentations and control technologies are included in the proposed design. Five samplers will be provided in order to monitor the plant products as well as internal process streams.

168/DOE/Qt r i yRep/ Jan-Mar -95 Page 29

The Semi-works capital cost estimate of the plant proper is approximately $10,915,000. Another $750,000 will be required for the purchase of land, start-up modifications, and working capital.

Construction Capital Requirement

Working Capital Requi rernent

Fixed Operating and Maintenance Costs

Variable Operating and Maintenance Costs

200 TPH Commerci a1 P1 ant Economic Analysis

$59,624,735 $59,547,893 $59,669,206

$467,723 $449,603 $478,500

$5,892,451 $5,892,451 $5,892,451

12,080,238 $11,158,134 $12,613,895

Based on the capital cost of the Semi-Works plant, the cost for 200 and 500 tons-per-hour facilities were extrapolated. In addition, fixed and variable, first-year operating-and-maintenance costs were estimated for these commercial plants. Table 1.03 presents a summary o f these costs for a 200 tons-per-hour (TPH) facility operating 7560 hours per year.

168/DOE/PtrlyRep/Jan-Mar .95 Page 30

Table 1.04 Advanced Froth Flotation Economics (Annualized Basis)

Cost Item

Clean Coal Price ($/MMBtu)

Clean Coal Price ($/Ton)

Annualized Desulfurization Cost*

II 200 TPH Commercial Plant Ooeratina 7.560 Hours Der Year II Pittsburgh No. 8 Upper Freeport Illinois No 6

1 49 1 50 1 55

40.65 40 27 41 96

$326.82 $305.42 $304 60

Cost Item



Annual Desul fur1 zati on Cost*

3456 ton.

Conc

Pittsburgh No. 8 Upper Freeport Illinois No. 6

1.81 1.81 1 87

49 32 48.68 50 63

$477.08 $442 49 $435 09

Due t o the l a rge cap i t a l requirements for these advanced p lan ts , operat ing schedule a f f e c t s cos t s t o a g r e a t e r ex ten t than plant s i z e . A typ ica l coal preparat ion f a c i l i t y opera tes f i v e days per week, two s h i f t s per day. Maintenance i s conducted on t he t h i r d s h i f t . This operat ing schedule r e s u l t s in 3456 hours o f operation per year and, a s t he cos t es t imates r evea l , a gross under u t i l i z a t i o n of f a c i l i t i e s . For t h e I l l i n o i s No. 6 coa l , a 200 TPH p lan t operat ing 7560 hours per year can remove sulfur for about $305 per t o n of SO, equivalent . When the same s i z e p l an t opera tes , only

hours per year , t he desu l fur iza t ion cos t climbs t o $435 per

Cost Item



Annualized Desulfurization Cost

us i ons

Pittsburgh NO. 8 Upper Freeport Illinols No 6

1.38 1.39 1 44

37.68 37.30 38.99

$275.27 $256.95 $259,84


Based on the f indings of t h i s p ro jec t , t he following conclusions may be drawn.

0

0

0

The proposed process technology i s ready for commercialization. However, t h e product from the process may requi re r econs t i t u t ion in order t o be marketable.

The proposed technology can recover 85 percent o f t h e energy in each of t he raw coa ls while removing 75 t o 80 percent of t he raw coa ls ' p y r i t i c s u l f u r .

Clean coal ash values of 7.2 t o 10.3 percent , on a dry bas i s , were achieved with the proposed technology.

0

0

0

Grinding t o l e v e l s f i n e r than 85 percent passing 200 mesh wi l l be required t o remove 85 percent of t h e raw coa l ' s p y r i t e while maintaining 85 percent energy recovery.

Based on raw coal c o s t s of $0.80 per mi l l ion B t u , c lean coal p r i ces of $1.50 per mil l ion B t u wil l be required for investments in the proposed technology t o earn a 10 percent a f t e r - t ax r a t e of r e tu rn .

Desulfur izat ion cos t s , on a d o l l a r s per t o n of SO, equiva len t , o f $255 t o $275 a re estimated for a 500 tons-per-hour commercial f a c i l i t y incorporat ing the proposed advanced f ro th f l o t a t i o n process.

The overal l ob jec t ive of the Kelsey cent r i fuga l j i g and Carpco MGS t e s t program was t o ve r i fy t h e amount of addi t ional p y r i t i c s u l f u r t h a t could be r e j ec t ed by subjec t ing the column f l o t a t i o n concentrate t o g rav i ty separat ion processes. Additional p y r i t i c s u l f u r r e j e c t i o n s of approximately 30% a re achievable with a B t u l o s s of only a few percent.

A review of the washabi l i ty analyses of the column f l o t a t i o n products i nd ica t e s t h a t a f a i r amount of s ink 2.0 mater ia l of very- h igh-pyr i t ic -su l fur content was in the column c e l l concentrate . This i s due t o the f a c t t h a t f l o t a t i o n i s dependent on sur face chemical p rope r t i e s and i s not a g rav i ty separat ion process. Since p y r i t e i s hydrophobic, i t tends t o f l o a t w i t h t he coal product . The microcel" column f l o t a t i o n c e l l was an improvement over conventional f l o t a t i o n c e l l s s ince i t used a deep f ro th bed and wash water which helped t o r e j e c t p y r i t i c mater ia l . Addi t ional ly , much of t h e p y r i t i c material t h a t f l oa t ed was due t o t h e f a c t t h a t t h e grinding process did not achieve t o t a l l i b e r a t i o n , and a l o t of t he py r i t e was s t i l l locked within the coal matrix. Review o f the da ta ind ica t e s t h a t t he column product contains about 3% s ink 2.0 a t approximately 20% p y r i t i c s u l f u r . A t best, based on t h e t es t results, g rav i ty separat ion o f t he column f l o t a t i o n product using devices such a s t h e Kelsey j i g o r Carpco MGS r e j ec t ed around 50% of t h i s mater ia l .

The f a c t t h a t so much high-pyri te containing s ink material was recovered by the Kelsey J i g and MGS was due t o the very f i n e

168/DOE/Qtr lyRep/Jan-Mar.95 Page 32

p a r t i c l e s i z e cons is t be ing t rea ted . However, t h i s was n o t t he on ly f a c t o r . The percent s o l i d s i n the g r a v i t y separat ion dev ice feed was a l s o impor tant , and i n t h e case o f t he Carpco MGS played a major r o l e . Apparent ly, t he percent s o l i d s i n Carpco MGS feed was t o o d i l u t e and caused a f l u s h i n g e f f e c t w i t h most o f t h e s o l i d s , i n c l u d i n g t h e h igh d e n s i t y so l i ds , f l o w i n g w i t h the water and r e p o r t i n g t o product . Actual Carpco MGS t e s t r e s u l t s had inadequate p y r i t i c s u l f u r r e j e c t i o n and e x c e p t i o n a l l y h igh Btu recover ies due t o t h i s f a c t .

The Kelsey j i g performance was n o t as s i g n i f i c a n t l y impacted by t h e d i l u t e na ture o f t h e feed ma te r ia l , b u t i t s performance cou ld be improved w i t h b e t t e r c o n t r o l o f feed s o l i d s content . The feed percent s o l i d s i n the g r a v i t y separat ion dev ice ranged from 7 t o 14%. I n re t rospec t , t he feed percent s o l i d s should have been inc luded as a t e s t parameter.

Since so l i t t l e r e j e c t ma te r ia l was produced by both g r a v i t y separators, t he re was i n s u f f i c i e n t r e j e c t ma te r ia l t o submit f o r w a s h a b i l i t y ana lys i s . I n one case t h e r e was a c t u a l l y i n s u f f i c i e n t ma te r ia l t o do a p y r i t i c - s u l f u r determinat ion. As such, samples o f t he g r a v i t y dev ice feed and product were submit ted f o r washab i l i t y . Th is i s t h e major f a c t o r why a "shotgun" s c a t t e r i n g o f performance Val ues was produced.

Based on the da ta co l l ec ted , an at tempt was made t o determine t h e probable e r r o r d i s t r i b u t i o n f a c t o r s f o r bo th o f t he g r a v i t y devices. The probable e r r o r values were then app l ied t o t h e washab i l i t y ana lys is f o r t h e column f l o t a t i o n concentrate and the q u a l i t y o f the Kelsey j i g and MGS were then ca l cu la ted based on t h e ash r e j e c t i o n , t o t a l s u l f u r r e j e c t i o n , p y r i t e s u l f u r r e j e c t i o n , and Btu recovery.

The f o l l o w i n g i s a summary o f t he c a l c u l a t i o n s . One must recognize t h a t these are ca l cu la ted values and are o n l y rep resen ta t i ve o f t h e r e s u l t s poss ib le i n combining column f l o t a t i o n and gravi ty-based separa t ion u n i t operat ions.

By combining separat ion operat ions, p y r i t i c s u l f u r r e j e c t i o n can be increased 7 t o 9% f o r t h e Kelsey j i g w h i l e sus ta in ing a 2 t o 3% a d d i t i o n a l Btu l o s s . Likewise, p y r i t i c s u l f u r r e j e c t i o n can be increased 6 t o 8% f o r t h e MGS w h i l e sus ta in ing an a d d i t i o n a l Btu l o s s o f on l y 0.5 t o 1.5%.

The goal o f t he advanced f l o t a t i o n p r o j e c t was t o achieve 85% p y r i t i c s u l f u r r e j e c t i o n and 85% Btu recovery. The da ta i n d i c a t e s t h a t t h i s goal was a t t a i n a b l e f o r t he I l l i n o i s No. 6 coal and poss ib le f o r t h e P i t t sbu rgh No. 8 and Upper Freeport . I f t h e g r a v i t y separat ing dev ices cou ld operate a t a lower separat ing g r a v i t y reducing t h e Btu recovery and inc reas ing t h e p y r i t i c s u l f u r r e j e c t i o n . Thus, t h e r e s u l t s poss ib le w i t h the combined advanced f l o t a t i o n / g r a v i t y separa t ion machine were very c lose t o t h e s ta ted p r o j e c t goal s .

168/DOE/Glt r 1 yRep/Jan-Mar .95 Page 33

Important findings resulted from the testing of the Kelsey Jig and Carpco MGS. Following are the conclusions derived from the test work and eval uat i on.

0 No exact quantitative concl usi ons can be determined because of the scatter in the performance curve data.

Substantial high pyritic sulfur remains in the microcel” column flotation concentrate product.

Although the microcel” flotation column is effective in rejecting well-1 i berated mineral matter such as ul trafine clay sl imes, other novel gravity separation-based devices are more efficient in removing composite particles containing a high specific gravity component such as pyrite.

Combining synergistically surface-based and gravity-based separation technology can substantially improve rejection of ash and pyritic sulfur contaminates than either separation device can alone.

The improved rejection of ash and sulfur contaminates can be accomplished with acceptable Btu losses.

Since the combined microcelTY flotation column/gravity separation circuit is effective in removing composite particles still containing unliberated pyrite, very fine grinding may be unnecessary.

The feed sol ids concentration to advanced fine particle gravity-based separation equipment must be regulated to obtain optimum performance. At too low feed solids concentrations, hydraul i c probl ems precl ude making a good gravity separation.

Commercial sizes of the Kelsey jig can process in excess of 10 TPH for the size material in the test program

Commercial sizes of the Multi-Gravity separator can process in excess of 5 TPH for the size material in this program.


16.0 TASK 16 POC MODULE REMOVAL


Th is t a s k i nvo l ves removing t h e POC module from t h e hos t f a c i l i t y , r e s t o r i n g t h e s i t e , and p r o t e c t i n g and sh ipp ing a l l Contractor- procured government p r o p e r t y t o PETC.

In decommissioning the process equipment, s t r i c t adherence t o removing process reagents and contaminants and t o capping and b lank ing a l l openings on t h e POC module and OCDO hos t f a c i l i t y i n t e r f a c e s . A1 1 government p r o p e r t y w i 11 be p r o t e c t e d from environmental damage p r i o r t o and d u r i n g shipment t o PETC. A l l DOE and OCDO host f a c i l i t y p roper t y w i l l be r e s t o r e d t o i t s c o n d i t i o n p r i o r t o t h e s t a r t o f Task 11.

16.2 Review o f Work Completed Th is Q u a r t e r

The DOE/PETC and OCDO reached a Personal Proper ty Loan Agreement concerning t h e DOE equipment. Th i s equipment w i l l be used by OCDO i n conduct ing f u t u r e a d d i t i o n a l coal p r e p a r a t i o n research a t t h e t e s t s i t e .

No a d d i t i o n a l work was p l anned o r completed d u r i ng t h i s qua r te r .


doe contract #de-ac22-88pc88881/67531/metadc... · quarterly technical progress report no. 26 for...

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