The extractive metallurgy of gold in South Africa, vol. 2

534 Pages·2016·3.53 MB·English

THE EXTRACTIVE METALLURGY
OF GOLD IN SOUTH AFRICA
VOLUME 2
SAIMM PUBLICATIONS
THE MONOGRAPH SERIES
Ml Lognormal-De Wijsian Geostatistics for Ore Evaluation
(2nd ed 1981)
D.G. Krige
M2 An Introduction to Geostatistical Methods of Mineral
Evaluation (2nd ed 1981)
J.-M.M. Rendu
M3 Principles of Flotation (1982)
Edited by R.P. King
M4 Increased Underground Extraction of Coal (1982)
Edited by C.J. Fauconnier and R.W.O. Kersten
MS Rock Mechanics in Mining Practice (1983) (3rd imp. 1986)
Edited by S. Budavari
M6 Assay and Analytical Practice in the South African Mining
Industry (1986)
W.C. Lenahan and R. de L. Murray-Smith
M7 The Extractive Metallurgy of Gold in South Africa,
2 volumes (1987)
Edited by G. G Stanley
THE SPECIAL PUBUCATIONS SERIES
SPl Proceedings, Underground Transport Symposium (1986)
Edited by R.C.R. Edgar
SAIMM PUBLICATIONS
THE SYMPOSIUM SERIES
S 1 Mathematical Statistics and Computer Applications in Ore
Valuation (1966)
S2 Planning Open Pit Mines (1970) (4th imp.)
Edited by P.W.J. van Rensburg
S3 Application of Computer Methods in the Mineral Industry
(APCOM 1973)
Edited by M.D.G. Salamon
S4 Infacon 1974
Edited by H. W. Glen
S5 Proceedings of the 12th CMMI Congress, 2 volumes (1982)
Edited by H. W. Glen
S6 Rockbursts and Seismicity in Mines (1984)
Edited by N.C. Gay and E.H. Wainwright
S7 The Planning and Operation of Open Pit and Strip Mines
(1986)
Edited by J.P. Deetlefs
SS GOLD 100: Proceedings of the International Conference on
Gold (1986)
Volume 1: Gold Mining Technology
Edited by H. Wagner and R.P. King
Volume 2: Extractive Metallurgy of Gold
Edited by C.E. Fivaz and R.P. King
Volume 3: Industrial Uses of Gold
Edited by G. Gafner and R.P. King
S9 APCOM 87: Proceedings of the Twentieth International
Symposium on the Application of Computers and
Mathematics in the Mineral Industries (1987)
Volume 1: Mining
Edited by L. Wade, R.W.O. Kersten and J.R. Cutland
Volume 2: Metallurgy
Edited by R.P. King and I.J. Barker
Volume 3: Geostatistics
Edited by I.C. Lemmer, H. Schaum and F.A.G.M. Cami
sani-Calzolari

The South African Institute of Mining and Metallurgy
Monograph Series M7
The Extractive
f 1 in S
Edited by
G. G. Stanley
VOLUME 2
This book was commissioned by the Sub-Committee of Consulting
Metallurgists of the Chamber of Mines of South Africa
Johannesburg
1987
Published by The South African Institute
of Mining and Metallurgy
Kelvin House, 2 Hollard Street, Johannesburg,
2001
©The Chamber of Mines of South Africa, 1987
P.O. Box 809, Johannesburg, 2000
ISBN 0 620 10944 0 Volume 2
0 620 10109 1 Volume 1
0 620 10945 9 The Set
Typeset by Scientific and Technical Typesetting
Kelvin House, 2 Hollard Street, Johannesburg 2001
Printed in the Republic of South Africa
by National Book Printers, Goodwood
Outline of Contents
VOLUME 1
page
Preface .......................................................................... . XXXl
Acknowledgements ........................................................... . xxxiii
Foreword by President, Chamber of Mines of South Africa ..... . xxxvii
Chapter 1 Geology and Mineralogy of the Principal Goldfields
in South Africa ............................................. . 1
Chapter 2 Sorting and Crushing ...................................... . 69
Chapter 3 Milling and Classification ................................ . 121
Chapter 4 Gravity Concentration .................................... . 219
Chapter 5 Flotation ...................................................... . 235
Chapter 6 Cyanidation ................................................... . 277
Chapter 7 Recovery of Gold from Solution by Cementation .. 331
Chapter 8 Pyrometallurgy of Gold .................................. . 345
Chapter 9 Application of Activated Carbon to Gold Recovery 379
VOLUME 2
Chapter 10 Refining of Gold at the Rand Refinery .............. . 615
Chapter 11 Disposal of Residues ...................................... . 655
Chapter 12 Retreatment of Residues and Waste Rock ......... .. 707
Chapter 13 Process Evaluation ......................................... . 745
Chapter 14 Process Control ............................................. . 793
Chapter 15 The Chemistry of the Extraction of Gold ........... . 831
Chapter 16 Plant Design and Commissioning ...................... . 907
Chapter 17 Loss Control and Safety Management ............... . 971
Chapter 18 Laboratories and Pilot Plants .......................... .. 1013
Tables and Formulae . .. .. .. .. . .. .. .. . .. .. . . . . .. .. .. .. .. . . .. .. . . . .. .. . . . .. .. .. 1053
Index.............................................................................. 1073
Vll
Contents
VOLUME 2
page
Chapter JO Refining of Gold at the Rand Refinery, by
K.G. Fisher . . . ........ ..... .. . ... . . .. . . . . . . .. . .. . . .. . .. . 615
10.l Introduction .......................................................... 615
10.2 Historical Development .. ..... ... .. .. . .. .... . . .. . .. . . .. .. .. .. .. .. . . 615
10.3 Function ............................................................... 616
10.4 Metallurgical Operations .. .. . . . . ......... .. .. . .. . .. . .. .. . . .. . . . .. . 618
10.4.1 Summary description .................................. 618
10.4.2 Gold Refining Branch .. . . ...... ... . . . . . . . .. . . .. . . . .. . . 618
10.4.2.1 Flow sheet 618; 10.4.2.2 Melting and
sampling 619; 10.4.2.3 Refining 621; 10.4.2.4
De-golding 626; 10.4.2.5 Electrolytic gold re-
fining 626; 10.4.2.6 Fume recovery and sweep
treatment 628
10.4.3 Silver Refining Branch ... . . ... . . ... . .. . . . ... ... . . . .. .. 630
10.4.3 .1 Flow sheet 630; 10.4.3 .2 Leaching and
reduction630; 10.4.3.3 Electrolytic silver refining
633
10.4.4 Coin blank production .. ........ .. . . . . .. .. . .. . .. . . . .. . 637
10.4.4.1 Historical 637; 10.4.4.2 Process de
scription 638
10.4.5 Smelter ...... ... . .. . ... . . . . . . .. .. . .. . . . . . . . . . . . .. . . ... . .. . . 641
10.4.5.l Flow sheet 641; 10.4.5.2 Sampling 641;
10.4.5.3 Blending and sintering 643; 10.4.5.4
Blast furnace smelting 644; 10.4.5 .5 Cupellation
648; 10.4.5.6 Panfurnacesmelting649; 10.4.5.7
Fume collection 651
10.4.6 Assaying and chemical analysis . .. . . . . . . .. . .. .. . .. . . 652
10.5 Future Developments . .... . .. . . .. . .. . . .. .. . . . . .. . . . .. . . . .. . . . . . . .. . . 652
10.6 References ............................................................. 653
Chapter II Disposal of Residues, by G.I. MacPhail and
J.C. Wagner ............................................ 655
11.1 Aim and Scope .. .. .. .. .. .. .. .. .. .. .. .. .. . .. . . . . .. .. .. .. .. . .. .. .. .. .. 655
11.2 Pianning . .. . . . . .... . .. .. . . .. . .. . .. . . .. . . . . . . . .. . . . .. . . . .. . . . .. . . .. . . .. . . 656
ix
CONTENTS
11.2.1 Components of a residue disposal system ...... . 656
11.2.2 Sizing ..................................................... . 657
11.2.2.1 Depositional area requirements 657;
11.2.2.2 Allowances for services 659; 11.2.2.3
Return water system660; 11.2.2.4 Total area660
11.2.3 Site selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 660
11.2 .4 Site exploration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 663
11.2.5 Pollution control considerations . . . . . . . . . . . . . . . . . . . . 665
11.3 Statutory Requirements .. . . .. . . .. . ... . .. . .. . ... ... . . ... . . . . . . . .. . . . 665
11.3 .1 Legal considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 665
11.3 .1.1 The Water Act 665; 11.3 .1.2 The Mines
and Works Act 666
11.3 .2 Licensing ................................................. . 666
11.3.3 Environmental impact assessment ................. . 666
11.3.3.1 Methods of assessment 667; 11.3.3.2
Remedial measures 667; 11.3 .3 .3 Monitoring 667
11.4 Design, Specification and Construction . . . . . . . . . . . . . . . . . . . . . . . 668
11.4 .1 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 668
11.4.1.1 General 668; 11.4.1.2 Method of for
mation of tailings dam 669
11.4.2 Tailings delivery ....................................... . 675
11.4.2.1 Pulp concentration 675; 11.4.2.2
Pumping and piping systems 676; 11.4.2.3 Pump
and pipeline design 678; 11.4.2.4 Tailings distri-
bution 678
11.4.3 Return water management .......................... . 678
11.4.4 Stormw ater management ............................ . 683
11.4.4.1 General 683; 11.4.4.2 Top surface of
dam 684; 11.4.4.3 Side slopes 684
11.4.5 Slope stability .......................................... . 685
11.4.5 .1 Influence of foundation soils 685;
11.4.5 .2 Influence of tailings product 685;
11.4.5.3 Influence of rate of rise 687; 11.4.5.4
Influence of phreatic surface 687; 11.4.5.5 In-
fluence of slope geometry 689; 11.4.5 .6 Stability
analysis 690
11.4.6 Repair and reinstatement of operational and aban-
doned impoundments .................................. 691
11.4.6.1 Common problems with old and aban-
doned dams 691; Remedial measures 693
11.5 Observation and Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 695
11.6 Closure Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 698
x