theemission ofmercuryfromgold-reduction worksinsouthafrica · 2009-08-27 · in metallurgical...

The emission of mercury from gold-reductionworks in South Africa

by H. H. E. SCHRODER*, Ph.D., M.Se.,A. VAN DER LlNDE*, B.Se. (Hons.), andN. B. STRYDOM*, Ph.D., M.Se., M.S.A.I.M.M.

SYNOPSISThis paper describes a study of the destination of the mercury that is present in the ore during the recovery of

gold.It was found that over 96 per cent of the mercury passse~ th~ough the proce~s unto~~hed. A small amoun~ ~nds

its way into cyanide solution, and is concentrated with gold m ZInCdust as Memll prec!plt~te.When the precipitateis calcined, the mercury is driven off and finds its way into the atmosphere. .I-!°wever, dilution of the stack ~as .m theatmosphere appears to be sufficient to prevent hazardous concentrations arisIng at ground level. No other significantconcentrations of mercury were found at any stage of the process.

The amount of mercury lost to the atmosphere by this mechanism appears to be less than 200 kg per year through-out the gold-mining industry in South Africa. . . . ...Virtually no mercury vapour could be detected m the air m the smelt-hc;>use. Slight mc~eases I~ mercury concen-trations above background level were observed in soils 3.round the reduction plants and m the discharge or returnwaters, but no environmental stress is anticipated from these .increases.

SAMEVATTINGHierdie referaat beskryf 'n studie van die lot van die kwik wat in spoorhoeveelhede in die erts voorkom tydens die

ontginning van goud. .. . .Dit is gevind dat 96 persent van die kwik onveranderd deur die proses gaan. 'n Klem hoeveelheld vmd e~ter. syweg na die sianiedoplossing vanwaar dit as Merril! presipitaat saam met ~oud gek~nse~treer wor~. Trdens kalsmermgword dit dan afgedryf in skoorsteenuitlate na die atmosfeer. Verdunnmg van die ultlaatgasse.," die atmosfe.er wasegter voldoende om gevaarlike konsentrasies op grondvlak te vermy. Geen noemenswaardlge konsentrasles vankwik kon by enige fase van die proses gevind word nie. . . .. .Die totale hoeveelheid kwik wat moontlik per jaar oor die hele goudmynbedryf van Suld-Afraka op hlerdle manlervrygestel word, word geraam op minder as 200 kg. ... .Bykans geen kwik kon in die werksatmosfeer in die smelthuis nagespoor ~ord nle. Germge ve.rhoglngs m agter-grondkwikkonsentrasies is in die grond rondom die reduksiewerke en in die afvalwater aangedul maar geen omge-wingsbesoedelingsgevaar word voorsien nie.

IntroductionMany metalliferous ores contain small amounts of

mercury!. Its presence in gold ores has long been known,but it has been ignored because of the difficulty of ana-lysing mercury in the presence of gold.

During the course of a research programme being con-ducted by the Research Organization of the Chamberof Mines of South Africa into the geochemical composi-tion of minerals occurring in the Witwatersrand reefs,it was found that gold particles contained on average1,38 per cent mercury, with some particles containingas much as 2,23 per cent. The measurements were madeby the Activation Analysis Research Group of theCouncil for Mineral Technology (Mintek) using nuclear-activation techniques. The question then arose as to whathappens to this mercury during the gold-refining process.

A first clue was offered by earlier studies of trace metalsin metallurgical plants2. Spark-source mass spectro-graphy, which is not a highly accurate technique, hadshown that the ore both before and after treatment, andall the solutions in the reduction works, contained lessthan about 0,1 p.p.m. of mercury. However, the goldprecipitate on zinc dust (Merrill precipitate) containedabout 50 p.p.m. of mercury, and the precipitate aftercalcining contained about 10 p.p.m. A loss of about40 p.p.m. thus appeared to occur at that stage.

It seemed desirable to confirm these findings and totrace the destination of the mercury. Consequently,samples were taken of solids and solutions at variouspoints in the reduction works on two mines. These mineswere chosen on the ground'! that neither now nor in the

* Industrial Hygiene Branch, Chamber of Mines ResearchOrganization, P.O. Box 809, Johannesburg 2000.

@ 1982.

past had they employed mercury for the amalgamationprocess, which is used on many mines. Thus, any mer-cury found would probably have come from the ore.

Experimental

Samples were taken of both solids and solutions at avariety of points in the plants. A flow diagram typical ofthe plants is shown in Fig. 1, in which the sampling pointsare identified by numerals. In addition, a survey wasmade of the atmosphere in and around the plant usingboth detector tubes and other instruments that gavemore quantitative results than the detector tubes.Analytical MetJwds - Solids and Liquids

The solids and slurries were digested overnight at50°C with an aqueous solution of hydrochloric and nitricacids, and were treated with ferric chloride in order toprevent mercury/gold amalgamation. This procedure wascarried out according to the method of Watling and DeVilliers3.

An aliquot portion (0,1 to 1 ml) of the digest or liquidwas introduced into a bubbler with a medium-porositysintered-glass bottom through which pure nitrogen gaswas bubbled. Stannous chloride (2 ml of 20 per centm/v aqueous) was added, and the mercury vapourreleased was collected as an amalgam on gold granulesfor subsequent analysis by atomic absorption.

Samples of Merrill precipitate and calcined precipitatewere analysed by a heating procedure. It was impossibleto analyse digests of these by the addition of stannouschloride since the large amount of zinc and gold presentmerely precipitated the stannous chloride. The samplesof Merrill precipitate were ball-milled overnight with fourtimes their mass of kieselguhr to give a fine sample fromwhich a sub-sample could be accurately weighed.

JOURNAL OF THE SOUTH AFRICAN INSTITUTE OF MINING AND METALLURGY JULY 1982 193

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The sub-samples were introduced into quartz tubesand were heated to about 700°C to release mercuryvapour, which was collected on gold granules for sub-sequent analysis.Analytical Methods for Mercury Vapour

Preliminary measurements were done using detectortu bes or commercial instruments based on the absorptionof ultraviolet radiation at 254 nm by mercury vapour.However, high concentrations of water vapour interferedwith this measurement. A commercial instrument basedon the conductivity of gold foil in the presence of mercurygave a quantitative check on the results of the detectortubes at low concentrations, but could not be used inatmospheres containing more than 0,5 mg/m3 of mercury.

At higher concentrations, an attempt was made ini-tially to use silver wool to absorb the mercury as anamalgam but, because of 'spill-over' and 'tailing' of thepeak, gold granules were eventually used. In this tech-nique, 2 g of 0,42 to 0,25 mm gold granules were held ina quartz tube of 6 mm internal diameter by glass-woolplugs. The air to be sampled was drawn through the tubeat a rate of O,ll/min until about 100 ng of mercury hadbeen absorbed on the gold. The tube was then heated toabout 700°C, and the mercury was carried off undernitrogen flowing at 0,25 l/min. It was re-absorbed on goldgranules contained in a similar quartz tube, which waspermanently connected to the analytical apparatus.Analysis of Mercury Collected on Gold Granules

The gold granules containing the mercury wereheated rapidly in a microfurnace to above 700°C, and themercury carried off was passed through a second quartz

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Fig. 2-Experimental set-up for the analysis of mercury inair, gold ore, and mill products

Atomic-absorption spectrophotometerRecorderAbsorption tubeHeating tapeMicrofurnace with standardized amalgamated tubepacked with gold granules

6. Microfurnace for release of mercury from gold-packed tubes used for air analysis

7. Sintered-glas bubbler8. Flow meter set at 0,25 I/min9. Flow meter set at 0,6 I/min

10, High-purity nitrogen supply11. Three-way taps

I.2.3.4.5.

tube in the optical path of an atomic-absorption spectro-photometer (AAS). The experimental set-up is shown inFig. 2.

The microfurnace was heated to 700°C in 2 seconds bypassing a high current (15 A) through 150 mm of heatingwire wound round the tube. The absorption tube washeated to 130°C to prevent condensation of water ormercury vapour. The concentration of mercury wasdetermined using a mercury hollow-cathode lamp withthe AAS set at 253,7 nm. Fig. 3 shows the recorder out-put during calibration with standard samples made upwith mercuric chloride. A near-symmetrical peak withvery little tailing was obtained.

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Fig. 4 shows the calibration chart, which is linear overthe range 20 to 100 ng of mercury.Emissions from the Calciner and Furnace Stack

The volume flowrates of air in the stack were deter-mined by use of a Pitot tube to measure the air velocitypressure and by calculation of the flowrate from the cross-sectional area of the stack, which was obtained by actualmeasurement of its dimensions. The temperature of theemissions was measured, as well as the ambient air pres-sure, so that the air density, and hence the air velocityand volume, could be calculated as described in TheVentilation of South African Gold Mines4.

Stack emissions were measured every hour, and thetotal mass emitted during one calcining cycle was calcu-lated by summing the amounts for each hour.

Results and DiscussionGeneral Mercury Survey

The results of the general survey of the two reductionworks are given in Tables I and n.


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TABLE ICONCENTRATIONS OF MERCURY FOUND IN SAMPLES TAKEN AT

VARIOUS POINTS IN REDUCTION WORKS R

I .MoIsturecontent

%

Concen-trationon drymassmg/kg

Sampling point

Concen-trationmg/kg

1. Tube-mill effluent

2. Brown tanks

3. Filter discharge to slimedams

4. Filter vats

5. Gold tank

6. BaITen liquor

7. Johnson press-MeITill

1stcycle2nd cycle

8. Calciner-dried MeITiIl

1stcycle2nd cycle

9. Soil at 100 m from stack

NW of stack

NE of stack

SE of stack

SW of stack

10. Water in dischargedam

I

11. Ambient air in smelt-house

0,4190,379

0,4720,080

33,858,8

0,6330,920

0,61122,8

0,034

71,926,6

45,542,1

0,1350,119

0,1350,119

0,991,211,260,32

0,011

0,009

Of particular importance is the fact that the mass ofmercury dropped only very little between the feed(tube-mill effluent) and the final discharge. For Plant R,the drop from 0,633 to 0,611 mg/kg was equivalent to aloss from the original ore of less than 3,5 per cent of themercury in the feed. For Plant S, the loss was less than3,8 per cent. Thus, in both cases the material was dump-ed very much as it was found.

The levels of mercury in the slimes were higher thanin many soils5, which typically contain 0,01 to 0,05mg/kg, but were at the same level as the maximum per-mitted level6 in fish used for food, namely 0,5 mg/kg.

Very little, if any, leaching of the mercury from slimesdams appeared to occur, as evidenced by a concentration

196 JULY 1982 JOURNAL OF THE SOUTH AFRICAN INSTITUTE OF MINING AND METALLURGY

TABLE IICONCENTRATIONS OF MERCURY FOUND IN SAMPLES TAKEN AT

VARIOUS POINTS IN REDUCTION WORKS S

Sampling pointConcen-trationon drymassmg/kg

Concen-trationmg/kg

Moisturecontent

%

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2. Brown tanks

3. Filter discharge toslime dams

Slime-dumps liquor

4. Filter vats5. Gold tank

6. Barren liquor

7. Johnson press--Merrill

1stcycle2nd cycle

8. Calciner-dried MeITill

1st cycle

2nd cycle9. Soil at 100 m from

stack:NW of stackNE of stackSE of stackSW of stack

10. Water in discharge dam

0,6020,369

0,7940,862

24,257,2

32,1 0,7640,5190,070

0,0190,061

30,039,9

44,359,9

3,730,407

31,036,0

3,730,407

3,592,100,071,49

13246

of a mere 0,070 mg/l in the slimes-dams liquor. Theconcentration in the discharge dam of one refinery wasalso low (0,011 mg/l). These values may be somewhathigher than some found for fresh water (0,00003 to 0,005mg/l)5, but are of the same order of magnitude as thoseproposed for drinking water6 (0,01 mg/l) by the WorldHealth Organization Congress in Helsinki.

The soil in the vicinity of the calcine stack showed highlevels of mercury (on average 0,945 and 1,813 mg/kg forthe two refineries). These are somewhat higher thanpublished values5 but water transport is unlikely, asevidenced by the low level of mercury in the water of thedischarge dam.

The flow of mercury once dissolved was not clear fromthis study. On Mine R the mercury level dropped betweenthe filter vats and the barren solution by an amount thatwas probably enough to account for the mercury in theMerrill slime. However, on Mine S the mercury levelactually increased between the gold tank and the barrensolution. This could possibly be attributed to the factthat water from the slimes dams was continuously re-turned to the circulating water.

A significant concentration of mercury was found in theMerrill precipitate on both plants. This level droppedduring calcining, which indicated that dissolved mercuryleft the plant at that stage. Table III shows the lossesas calculated (84,69 and 32,28 g for refinery Rand Srespectively). These are equivalent to 444 and 103 mg/kgof gold produced for refineries Rand S respectively. Fora total annual production of 706 t of gold for the entireSouth African gold industry 7, this would amount to193 kg of mercury per annum. This is still only 2 per centof the speculative amount of 9,7 t. It is very little com-pared with an estimated world-wide total of 3000 t ofmercury being emitted per year as a result of the burningof coals and fossil fuels8.

First cycle

Mass of feed, kg 480,0 395,5Mercury in feed, fig/kg 132,0 44,3Mercury in feed, g 63,36 17,52Mass of product, kg 436,0 387,0Mercury in product, fig/kg 0,135 3,73Mercury in product, g 0,059 1,44Loss in first cycle, g 63,30 16,08

Second cycle

Mass of feed, kg 466,1 272,3Mercury in feed, fig/kg 46,0 59,9Mercury in feed, g 21,44 16,31Mass of product, kg 453,0 272,0Mercury in product, fig/kg 0,119 0,407Mercury in product, g 0,054 0,111Loss in second cycle, g 21,39 16,20Tota11oss, g 84,69 32,28

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TABLE IIII,OSS OF :MERCURY DURING CALCINATION OF :MERRILL PRECIPI-

TATE

MineR Mine S

Emissions of metallic mercury vapour by way of thecalcine stack gas were less than the losses on calcining.They amounted to only 13,2 and 20,8 per cent of the losson calcining for the two refineries (see below). It thusappears that mercury may leave the calciner in a formother than metallic.

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Atmospheric SurveyWith the detector tubes, which had a minimum detect-

able limit of 0,05 mgfm3, no mercury could be found inthe working environment. ThiR was confirmed with thegold-foil meter, which measured a maximum concen-tration of less than 0,009 mgfm3 in the smelt-house. Thesevalues can be compared with normal air levels of 0,0006to 0,05 mgfm3 or levels over the ocean;8 of 0,0006 to0,0007 mgfm3.

No mercury could be detected in the air over any ofthe processes in the two mines, including the electric-arcfurnace, except in the stack gases from the calciner.There the detector tubes indicated over 2 mgfm3 and thegold-foil meter went off scale.

These results suggest that the mercury moved alongwith the gold in the refining process and that it wasdriven off at-the calcining stage. Here the Merrill precipi-tate was being heated to between 580 and 780 °C, atwhich temperature the mercury could be expected to beeasily released (boiling point: 357°0) Accordingly, thestack gases were the subject of careful study.Survey of Calcine Off-gases

The results of a survey using the amalgamation ofmercury from air onto gold granules are presented graph-ically in Figs. 5 and 6. A maximum concentration of7,41 mgfm3 for refinery R and of 1,49 mgfm3 for refineryS was found. These values are far in excess of the allow-able threshold limit value (TLV) of 0,05 mgfm3 as pro-

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posed by the American Conference of GovernmentalIndustrial Hygienists (ACGIH) for occupational atmos-pheres. However, as the volume flowrates off the stackwere low (0,1315 m3fs for mine Rand 0,1224 m3fs formine S), the dilution factor of 150, which would berequired to dilute the mercury concentration of the stackgas to below 0,05 mgfm3, should quickly be reached witheven the slightest breeze. Furthermore, mercury vapouris emitted at levels above the TLV for only short periodsof time (see Figs. 5 and 6). The average values wouldtherefore be well below the peak values.

An integration of the emission rates over the calciningperiod (two cycles each) gave a total of 1l,l50 g of mer-cury for refinery Rand 6,708g for refinery S. Theseamounted to only 13,2 and 20,8 per cent respectivelyofthe estimated amounts lost during calcining (Table Ill).The reasons for this appear to be that

(i) it was difficult to measure the air flow accuratelysince it was irregular and was entirely due tothermal convection currents;

(ii) very low pressure differences found on the mano-meter (5 mm 'silane' for 1 :10 incline) were alsodifficult to measure accurately; and

(iii) only mercury vapour was collected on theTgoldgranules, and mercury in another form could_haveescaped in the off-gases.

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This escape of mercury was evidenced by the presenceof a considerable amount of mercury (1,894 g) in waterthat had condensed in the sampling apparatus during theisokinetic sampling of the off-gas. Furthermore, duringthe latter part of the second calcining on mine S, whenthe temperatures were generally below 75°C, there wereseveral 'erratic' samples such as would be expected ifparticulate mercury werc present (see Fig. 6).

Conclusions

A survey of the destination of the mercury that occurI';in trace amounts in ore during the refining of gold showedthat

(1) most of the mercury in the feed (more than 96 percent) passes untouched through the process;

(2) the small amount of mercury that leaves the oreduring processing does not appear to concentrateanywhere in the process except in the Merrillprecipitate; when this precipitate is calcined,typically twice a week, between about 30 and 90 gof mercury is released;

(3) the release of mercury during calcining results inpotentially hazardous concentrations of mercuryvapour in the off-gas, and up to 80 per cent of themercury probably also condenses and is lost asparticulate matter;

1.490 1.024

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....

2 nd Calcining

10 14Time of day

18 22 2

198 JULY 1982

Fig. 6-Concentration of mercury vapour in stack-gas emissions from calciner. D1ine 5

JOURNAL OF THE SOUTH AFRICAN INSTITUTE OF MINING AND METALLURGY

(4) if the results on the loss during calcination areextrapolated to the whole industry, an annualloss of less than 200 kg can be expected from thissource;

(5) although relatively high peak concentrationswere measured in the off-gases during calcination,no hazardous concentrations of mercury could befound in the working environment; however, thesoils in the vicinity of the smelt-house seemed tocontain slightly larger amounts of mercury thanwere present naturally;

(6) there is reasonable confidence that the sole poten-tial hazard arising from mercury lies in the cal-ciner off-gases; the peak concentration of some7 mg/m3 that was observed in this stream wouldprobably be rapidly diluted to background levelsin the open air.

Acknowledgement

The authors thank the Chamber of Mines of South

Africa for permission to publish this paper, and Dr P. J.D. Lloyd for his contribution.

References

1. KNIGHT, A. L. Mercury and its compounds. Occupationalmedicine. principles and practical applications. Zenz, C.(editor). Chicago, Year Book Medical Publishers, 1975.p.675.STRASHEIM,A. Private communication.W ATLING,R. J., and DE VILLIERS, D. J. A slotted quartztube for increasing sensitivity in flame atomic absorption.Pretoria, C SIR, F.I.S. Report 108, 1977.THE MINE VENTILATION SOCIETY OF SOUTH AFRICA. Ventila-tion of South African gold mines. Johannesburg, the Society,1974. pp. 275 - 285.MACINTYRE,A. R. Toxicities of mercury and its compounds.J. alin. Pharm., Nov./Dec. 1971. pp. 397 . 401.VIRARAGHAN,T. Mercury pollution. Water waste treatment,vo!. 14, no. 8. 1971. pp. 8 . 9.CHAMBER OF MINES OF SOUTH AFRICA. 1979 year.end review,December Report, p. 6.DRONE, P. The primary air pollutants. gaseous. Air Pollu-tion. 3rd Edition. Stern, A. C. (editor). Academic Press 1976.cf GOLDSMITH, J. R. and FRiBERY, L. T., loco cit. 1976, p.545.

2.3.

4.

5.

6.

7.

8.

Wire Association InternationalAn international group of leading experts and innova-

tors in the wire industry will be on hand at the WireAssociation International's 51st Annual Convention toshare their knowledge and experience in a series oftechnical sessions, seminars, and workshops. The tech-nical conference is being held concurrently with theInterwire '81 exposition at the World Congress Center,Atlanta, Georgia, U.S.A., from 13th to 16th October,1981.

Last year, more than a thousand members of theindustry participated in the conference programme,studying developments that hlCluded controlled coolingprocesses in ferrous technology, multiple-strand wiredrawing, and computer control of wire machinery, aswell as discussing the environmental considerations inwire drawing, the handling of powdered chemicals, andthe reclaiming of lubricants.

This year's programme offers 40 technical papers tohelp all segments of the wire industry to keep abreast

of changing technology and design concepts. The techni-cal sessions are divided into eight theme programmes forthe ferrous, non-ferrous, and electrical segments of thewire industry. They include:

. Cleaning and Coating of Ferrous Wire

. From Cathode to Wire

. Concepts for Electrical Wire and Cable. Review of Wire Breaks: An Update. Process Control. New Directions: Management, Microprocessors, andFabrication

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Corrigenda: May 1982The following corrections should be made to page 137

of the May 1982 issue (vol. 82 no. 4) in the paper ofR. J. Mason entitled 'Prehistoric mining in South Africa,and Iron Age copper mines in the Dwarsberg, Transvaal.'

The first paragraph line thirteen should read: "Untilthis is done, the earliest acceptable date in South Africafor a mine is A.D. 770:1:80".


SPOTLIGHT onthe 12th CMMI Congress

The 12th Congress of the Council of Mining and Metal-lurgical Institutions was held in .Johannesburg from23rd April to 21st May, 1982, the technical sessionsrunning from 3rd to 7th May. The background to thi8Congress has already been described1, and this presentarticle highlights only the aspects that, in retrospect,seem to be of particular interest.

Registrations

A few statistics are given below.

Apart from South Africa, 28 different countries fromEurope, North and South America, the Middle and FarEast, and Australasia were represented, the biggestcontingents, predictably, coming from Australasia (80delegates, 49 affiliates), Canada (48 delegates, 33 affi-liates), and the United Kingdom (36 delegates, 21affiliates).

The numbers generally were considerably higher thanthose recorded at the 1961 Congress, and the 12thCongress was thus, in the words of the S.A. CongressBureau, 'one of the most successful truly internationalevents held in our country so far this year'.

Technical Programme

The Technical Programme Conunittee, under chair-man Henry James, faced a formidable task with some200 papers being offered, of which 83 were finally accep-ted for presentation2. There were also 11 plenary address-es and 38 poster presentations2. In order to fit all the

*Congress Manager, Chamber of Mines of South Africa, P.G.Box 61809, Marshalltown 2107, Transvaal.

(!J 1982.

by CHARLES MACPHAIL*

papers and plenary addresses, together with theopening and closing ceremonies, into the three daysallowed, four parallel sessions were run for the paperson two of the days and five on one day. This arrangementappeared to work satisfactorily, and the technical ses-sions were generally well attended and the papers wellreceived.

Delegates were particularly impressed by the calibreof the plenary speakers, who are listed later with the sub-jects oftheir addresses2.

Among other things, the technical sessions served tohighlight the inadequate facilities available in Johannes-burg for a conference of this size. In addition to the wholeof the functions and ballroom floors at the Carlton Hotel,three theatres of the Kine Complex had to be hired tohouse the plenary and three of the parallel technicalsessions. Situated on the north side of CommissionerStreet directly opposite the Carlton Hotel, the facilitiesprovided by the Complex were more than adequate.

Another feature of the technical sessions that shouldbe mentioned is the provision of preprints of the papers.Early on in the organization, it had been decided toprovide each delegate with a booklet of abstracts of thepapers rather than a full set of preprints, many of whichwould be of no interest to him. Shortly before the Con-gress opened, it became obvious that there would be ademand for preprints. Rapidly and efficiently put to-gether by Dave Viljoen and Henry James, a photocopy-ing organization was set up at Congress headquarterswhich, for a nominal fee, could provide delegates withcopies of any papers that they might require. This orga-nization proved to be extremely popular, and some 3500copies were produced during the Congress and for a short

Delegates Affiliates Total

Total registrations - South African

- Non South AfricanTotal

Absentees - South African


Actual participants - South African


743327

1070

1--1~

-

27

1022482

1504

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200 JULY 198Z JOURNAL OF THE SOUTH AFRICAN INSTITUTE OF MINING AND METALLURGY

Mr L. W. P. Van den BoschMr J. Ogilvie ThompsonMr J. H. SmithMr R. S. LawrenceMr R. A. PlumbridgeMr E. PavittMr G. H. WaddellMr P. E. StreicherDr T. F. MullerDr J. G. H. Loubser

Mr B. E. Hersov

List of Plenary Speakers

The changing face of the South Mrican mining industryThe international diamond industryEscom from the present to the twenty-first centuryThe Soutn African coal-mining industryThe gold marketThe nuclear-power industry -The platinum industryChromium and ferro-alloysA survey of the South African steel industryThe South African transport services take up the challenge

of mass transportThe South African labour scene: quo vadis ~

period after it. The provision of a full set of preprints forevery delegate would have required some 87 000 copies,and it is thus felt that an organization of this type, butset up in time to have a small stock available at the startof a congress, is the correct answer to this problem.

A major problem facing the organizers of any congressis the lack of opportunity for trial runs or rehearsals.Everything has to be right first time. As far as the tech-nical sessions were concerned, this problem was solved bysome of the bigger organizations such as Mintek, some ofthe mining Groups, and the Chamber of Mines ResearchOrganization, who held in-house practice sessions forthose members of their staff who were presenting papers.Allied to this was the provision of a desk at Congressheadquarters at which authors handed in the slides for

checking and placing in the correct cassettes. Theseprecautions contributed largely to the fact that practi-cally all the sessions finished on time and, as far as canbe ascertained, the correct slides were always availableat the right time and place and there were no embarrass-ing incidents of missing, out-of-sequence, back-to-front,or upside-down pictures on the screens.

Posters

The Posters Committee started out as a section of theTechnical Programme Committee but, as the volume ofwork built up, it became a separate organization, al-though its members all remained on the original commit-tee.

The official poster sessions at the Congress were from

A toast to the State PresidentFrom left: Professor M. G. Fleming (President of the Council of Mining and Metallurgical Institutions), Mrs M. de Klerk,the Honourable A. L. Schlebusch (Vice State President), the Honourable F. W de Klerk (Minister of Mineral and EnergyAffairs), and Mrs I. E. Schlebush

JOURNAL OF THE SOUTH AFRICAN INSTIHJTE OF MINING AND METALLURGY JULY 1982 201

12h30 to 14hOO and from 16h30 to 17h30 on Monday,3rd, and Wednesday, 5th May. However, the posterswere in position for the whole day on these days, anddelegates were free to visit them at any time.Attendances on the Monday, possibly due to delegates'unfamiliarity with this form of presentation, were ratherJow, but on the Wednesday things were much morelively and authors in general were very pleased with theresults.

Poster presentations are an innovation at CMMIcongresses, but there is no doubt that their potential fordetailed and extensive discussions on specialist subjectsmakes them a most useful addition to the usual technicalpapers. This first-time effort can be regarded as mostsuccessful. The standard of presentation was extremelyhigh, and some useful lessons were learnt for the future.

Tours

The tours programme was arranged with the twinobjectives of covering the full spectrum of miningactivity in South Africa while at the same time allowingdelegates to see as much of the country as possible. Ithad to be flexible enough to cater both for those whoseavailable time was short, and for those who were able tospend a full four weeks in South Africa.

With these objectives in mind, a programme of sevenshort pre-congress tours was arranged, most of whichwere repeated in the course of the longer post-congresstours. Abbreviated itineraries of the various tours aregiven below.

The tour itineraries were designed by the CongressManager, but the detailed planning and implementationwere almost entirely in the hands of the tour managersand the S.A.R. Travel Bureau. The tour managers wereall senior officials on loan from the mining Groups, andthe undoubted success of the tours was due in no smallmeasure to the tremendous effort that they and theS.A.R. personnel put into them. All would, of course,have been in vain without the willing co-operation of themanagements and personnel of the mines and industrieRvisited. Their enthusiasm and hospitality made a tremen-dous impression on all. The faet that every delegate andaffiliate who participated in the tours returned toJohannesburg eompletely convinced that his or her tourhad undoubtedly been the best is perhaps the hesttribute to all those who were involved.

Local Visits

On Tuesday, 4th May, Congress members were theguests of the gold-mining industry at local gold mines,while on Thursday, 6th May, a wide variety of visits wasarranged to local mines, industries, and areas of geologi-cal interest, including an archaeological trip to MelvilleKopjes and Sterkfontein caves.

On both these days, the Congress Manager was facedwith considerable transport problems in that participantshad to be collected from four hotels and transportedduring the morning rush hour to the Carlton Hotel,where they were joined by a large number of local dele-gates and redistributed, on Tuesday among 14 buses and

Pre-Congress Tours

Al De Beers, Kimberley, Gong-Gong alluvial diamond diggings, Ulco lime quarry, Sishen iron oremine, and the manganese and asbestos mines of the Kuruman area.

A2 Chromore and Chrome Chemicals mines, Impala and Rustenburg platinum mines, Thabazimbiiron, and Rooiberg tin.

A3 The West Wits., Klerksdorp, and Welkom goldfields.A4 Rietspruit and Kriel collieries. Evander goldfield, Sasol Il and Ill, Middelburg Steel and Alloy

Company.A5 Palabora, Foskor, Kruger Park, Lavino Chrome, Tubatse Ferrichrome, and Consolidated Mur-

chison.A6 Botswana including Selibi-Phikwe, Orapa, and the Okavango swamps.SI South West Africa/Namibia including Consolidated Diamond Mines, Langer Heinrich and Rossing

uranium, Tsumeb, and Etosha game park.

Post-Congress Tours

Tour Al plus Black Mountain, O'Kiep, De Beers Kleinzee, and Cape TownCape Town, Saldanha Bay, O'Kiep, Black Mountain, De Beers Kleinzee, Sishen, Finsch diamondmine, and Northern Lime quarry and cement works.Tour A2 plus Palabora, Foskor, Kruger Park, and Duvha colliery and power station.Tour A3 plus Cape Town including Saldanha Bay, Koeberg nuclear power station, the Steenbrasscheme, and return to Johannesburg by Blue Train.S.A. Coal Estates, Evander goldfield, Sasol Il and Ill, Highveld Steel and Vanadium, KrugerPark, Richards Bay Minerals, Alusaf, Richards Bay Coal Terminal, and Durban.Royal Natal National Park, Drakensberg pumped storage scheme, Iscor Newcastle, HighveldSteel and Vanadium, Kruger Park, Pilgrims Rest, Winterveld Chrome, Penge Asbestos, andBuffalo Fluorspar.Durban, Richards Bay as for Tour D4, Havelock Asbestos, Eastern Transvaal Cons., KrugerPark, Sa sol Il and Ill, Matla eolliery, and Middelburg Steel and Alloy Company.Same as A6.Same as SI but with two extra days at Etosha.

DlDIA

D2D3

D4

D4A

D5

D6S2


on Thursday among 17. The potential for chaos wasfrightening but, with advice and assistance from the,Johannesburg Traffic Department and under the ablei>upervision of Dennis Malan and Wally van der Meulen,together with Ivan Botha of the S.A.R. Travel Bureau,things went remarkably smoothly.

As with the main tours, the host organizations wentto great lengths to ensure the success of these visits, andmany enthusiastic reports were received from thedelegates who participated in them.

A disappointing feature that applied particularly tothe gold-mine visits was the number of delegates andaffiliates who booked for a trip and failed to put in anappearance. This was most frustrating for the hosts andembarrassing for the organizers, especially as delegateshad had to be turned away from tours that had beenfully booked.

No description of local visits would be complete with-out mention of the excellent programme that theWomen's Planning Committee put together for affiliateson technical session days. On the Monday, immediatelyafter the opening ceremony, they were taken to RandAfrikaans University to visit the Living Arts BiennialExhibition, followed by lunch and a performance by awomen's choir from Soweto.

On Wednesday, they were able to visit the magnificenthome and garden of l\lrs Bridget Oppenheimer and alsogo on a sightseeing tour of Johannesburg, while on Fridaythey had a choice of sightseeing in Pretoria, a visit toSowcto and Lenasia, or an archaeological tour similarto that organized on the previous day.

These tours were all highly successful and much appre-ciated by the participants. This seems an appropriateplace to mention, however, that they were only part ofthe activities of the Women's Planning Committee, whoput in a tremendous amount of work in assembling andpacking the contents of the brief-bags for all delegatesand affiliates, in manning the registration desks, assistingwith transport, organizing private hospitality, and manyother duties. Congress was fortunate in having such anenthusiastic and efficient band of workers.

The Social Side

It might be alleged that the main tours were one longsocial function but this would not be strictly true; infact, one of the features of the Congress was the abilityof delegates and their wives to enjoy to the full the oftenlavish parties in the evenings and still get up early thenext morning, not always without mild protest, to par-ticipate in the technical tours.

Be that as it may, the three official functions during

Congress week were the welcoming reception, the StateBanquet, and the farewell function. The welcomingreception, given by the Chamber of Mines and hosted bythe President, l\Ir L. W. P. van den Bosch, took the formof a cocktail party and buffet supper, while a cheese andwine party was organized as the farewell function. Boththese functions were held at the Carlton Hotel, and werewell attended and most enjoyable with many favourablecomments on the standard of food and drink provided.

Highlight of the week, however, was undoubtedly theState Banquet, at which the Minister of Mineral andEnergy Affairs, Mr F. W. de Klerk, was the host and theHonourable l\Ir A. L. Schlebusch, Vice State-President,the guest of honour. Held at the Alberton Civic Centrein the absence of any suitable venue in Johannesburg,it was attended by some 1400 Congress members andother guests; including several Cabinet Ministers, andwas a most successful and impressive function. This isperhaps not the place to go into details of the elaborateorganization that was required. They will be reportedelsewhere3, as will the speech by l\Ir Schlebusch2 and thereply by Professor Fleming2. Suffice it to say that thebanquet was the result of a most harmonious co-opera-tion between the Congress management, the Chamber ofMines' Public Relations Department, and severalGovernment departments, including the South AfricanTransport Services, who were responsible for the excel-lent catering.

Omissions

It must be mentioned again that this account doesnot claim to be a complete record of the 12th CMMICongress. Much more could be written, and many moreindividuals who deserve mention could be named.

A major omission is the computer programme on whichJohn Austin and his colleagues spent so many long hoursand which covered every facet of the Congress. It is feltthat it merits a Spotlight on its own.

No mention, either, has been made of two features thatmany overseas delegates pin-pointed as highlights of theCongress: the arrangements for meeting them at theairport, and for their entertainment in private homes atthe weekends. These will be reported elsewhere2.

1.References

VILJOEN, D. A. Spotlight on the Council of Mining andMetallurgical Institutions and the 1982 Congress. J. S. Afr.Inst. Min. Metall., vol. 81, no. 2. Feb. 1981. pp. 51 - 53.GLEN, H. W. (Editor). Proceeding8 of the 12th OMMIOongre88, Johanne8burg, 3rd to 7th May, 1982. (To bepublished in 2 vols.).MACPHAIL,C. S. To be published.

2.

3.


THE SOUTH AFRICAN INSTITUTE OF MINING AND METALLURGY

Information on Membership

Tbe Institute was founded in 1891 asthe Chemical and Metallurgica] Society ofSouth Africa. In 1904 it was reconstitutedas the Chemical, Metallurgical and MiningSociety of South Africa, and in 1956 itbecame the South African Institute ofMining and Metallurgy.

The objects of the Institute are toadvance the science and practice of miningand metallurgy, to afford opportunities forthe interchange and recording of know-ledge about mining and metallurgy, andto ensure high standards of professionalconduct and competence.

Membership benefits include monthlyissues of the Journal of the Institute;m,*tings and discussion groups; colloquiaand symposia at which papers are read;excursions to mining and industrial con-cerns; va('-ation schools usually prosen tedby overseas 'course ]eaders'; annualmonograph publications; and the use ofclub facilities at Ke]vin House. Technicaljournals received on an exchange basisare available to members at the Johannes-burg Public Library. The current member-ship of the Institute is 2146.

The Institute consists of corporate andnon-corporate members, all of whom areentitled to attend and speak at meetingsof the Institute, but only corporate mem-bers are able to vote. The grades ofHonorary Life Fellow, Fellow, andMember constitute corporate membership.

Membership applications are acceptedfrom suitably qualified persons, and therequirements for entrance to the variousgrades of membership are summarizedbelow.

Honorary Life Fellows shall bepersons whom the Institute speciallydesires to honour in consideration ofservices rendered to the Institute, science,or industry. The eleetion is by ballot andrequires the unanimouQ vote of the Couneilmembers present.Honorary Fellows shaH be persons of

distinction in publie service, s('i,~nce, orthe arts; they are elected for th9 cnrrentyear, and enjoy all the privile.ges andrights of members, except those of holdingoffice and voting.

Fellows shall be not ]E>SSthan 30 yearsof age, and shall be university graduates inpure or applied science or shall produceevidence to the satisfaction of Councilthat they have successfully completed aco-ordinated course of study in pure orapplied science of at least four years'duration at an approved university orinstitution deemed by Co unci] to be ofequivalent status. Fellows shall have been

employed in senior technical positions inimportant mining or metallurgical under-takings, or in government, educational,

,or.research organizations concerned withthose industries, for at least five years orthey shall have practised as mining ormetallurgical consultants for at least fiveyears. They shall be practising theirprofession at the time of application.Council shall be satisfied that the trainingand technical experience of any candidatepractising as a consultant justify suchprofessional status.

Entrance fee RIO,OO, Annual subscrip-tion R35,00.

Letters of designation: F.S.A.I.l\I.M.Members shall be not less than 25

years of age and shall be universitygraduates in pure or applied science, orshall have successfully completed co-ordinated courses of study in pure orapplied science of at least four years'duration, or an honours degree at anapproved university or institution ofequivalent status. They shall have beenengaged in work of an approved technicalcharacter in the mining or metallurgicalindustries, or in government, educational,or research organizations connected withthose industries, of which not less thantwo years shall have been in positions ofresponsibility. A candidate shall bepractising his profession at the time of hisapplication.

Entrance fee RI0,00, Annual subscrip-tion R30,00.

Letters of designation: M.S.A.I.M.l\I.Associate Members shall be not less

than 30 years of age, and shall have beenengaged in a position of responsibility in,or associated with, the mining or metal-lurgica] industries or allied professions fornot less than ten years, of which fivevears shall have been in a senior technicalposition in major mining or metallurgicalundertakings, or in government, educa-tional, or research organizations Con-cerned with those industries.

Entrance fee, RIO,OO, Annual snbscrip-tion R30,00.

Associates shall be not less than 25years of age, and shall have been engagedin positions of responsibility in, or associ-ated with, the mining or metallurgicalindustries for periods of not less than threeyears. If, however, the candidate foradmission to the higher grade of Associateis at the time of his application already aStudent, he need satisfy the Council onlythat he is, at the time of his application,engaged in a position of responsibility inor associated with the mining or meta]-

lurgical industries. In all cases the appli-cants shall satisfy the Council that tbeyare fit and proper persons to becomeAssociates.

Entrance fee RIO,OO, Annual subscrip-tion R30,00.Graduate Members shall be not less

than 21 years ofB,ge and shall be universitygraduates in pure or applied science, orhave completed co-ordinated courses ofstudy in pure or applied science of atleast four years' duration, or an honoursdegree at an approved university orinstitution of equivalent status, and shallbe engaged in approved mining or metal-]urgical undertakings or in government,educational, or research organizationsconcerned with those industries. Theyshall not remain Graduate Members afterattaining the age of 30 years without thepermission of Council, or after obtainingthe requisite qualification for transfer.

Entrance fee R2,50, Annual subscrip-tion R20,OO.

Student Members shall be persons notless than 18 years of age who are beingeducated or trained in a manner approvedby Council to occupy a technical positionin or associated with the mining or metal-lurgical industries and who, furthermore,shaH not have attained the qualificationrequired for a higher grade of membership.They may remain Student Members untilthey have obtained the necessary qualifi-cations for transfer to a higher grade ofmembership, but not after the end of theInstitute's financial year in which theythey attain the age of 28 years. They shallthen transfer to a higher grade to retainmembership of the Institute. The Councilmay relax the provisions of this clause insuch cases as it considers appropriate.

Entrance fee nil, Annuli.] subscriptionR5,00. (Payab]e on application.)

Company Affiliates shall be com-panies involved in, or associated with, themining and metallurgical industries.

Entrance fee nil, Annuli.] subscriptionR250,00. (Payable on 1st July each year.)

Other. The Council has the power toelect to the grade of Fellow or Membercandidates who may not fulfil all therequirements for entrance to these gradesbut whose status, professional achieve-ments, and practical experience in miningor metallurgy justify such election.

Applications. Requests for member-ship application forms should be addressedto the Secretaries, South African Instituteof Mining and Metallurgy, p.a. Box 61019,Marshalltown,2107.


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