Table Of ContentInternational Series on
MATERIALS SCIENCE AND TECHNOLOGY
Volume 41—Editor: D. W. HOPKINS, M.Sc.f
PERGAMON MATERIALS ADVISORY COMMITTEE
Sir Montague Finniston, Ph.D., D.S.c., F.R.S., Chairman
Professor J. W. Christian, M.A., D.Phil., F.R.S.
Professor R. W. Douglas, D.Sc.
Professor Mats Hillert, Sc.D.
D. W.Hopkins, M.Sc.t
Professor W. S. Owen, D.Eng., Ph.D.
Mr. A. Post, Secretary
Professor G. V. Raynor, M.A., D.Phil., D.Sc, F.R.S.
D. M. R. Taplin, D.Sc, D.Phil., F.I.M.
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ROBERT MAXWELL
Publisher at Pergamon Press
Mineral Processing
Technology
FOURTH EDITION
AN INTRODUCTION TO THE PRACTICAL ASPECTS OF
ORE TREATMENT AND MINERAL RECOVERY
by
B. A. WILLS, BSC, PHD, CENG, MIMM
Principal Lecturer
Camborne School of Mines, Cornwall, England
PERGAMON PRESS
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Copyright © 1988 B. A. Wills
All Rights Reserved. No part of this publication may be
reproduced, stored in a retrieval system or transmitted in any
form or by any means: electronic, electrostatic, magnetic
tape, mechanical, photocopying, recording or otherwise,
without permission in writing from the publishers.
First edition, 1979
Second edition, 1981
Reprinted 1982
Third edition, 1985
Fourth edition, 1988
Library of Congress Cataloging in Publication Data
Wills, B. A. (Barry Alan)
Mineral processing technology.
(International series on materials science and
technology; v. 41)
Includes index.
1. Ore-dressing. I. Title. II. Series.
TN500.W54 1988 622'.7 87-14244
British Library Cataloging in Publication Data
Wills, B. A.
Mineral processing technology: an
introduction to the practical aspects of
ore treatment and mineral recovery.—
4th ed.—(International series on
materials and technology, v. 41).
1. Ore-dressing
I. Title
622/7. TN500
ISBN 0-08-034937-4 Hardcover
ISBN 0-08-034936-6 Flexicover
Printed in Great Britain by A. Wheaton & Co. Ltd., Exeter
This book is dedicated to my wife
Barbara for her tolerance and patience
PREFACE TO THE FOURTH EDITION
SINCE the publication of the third edition of this book, the fortunes of
the world's minerals industry have not improved significantly,
particularly in the base metals sector, where falling or stagnant metal
prices have forced many mines to shut down or cut back on production.
In view of the low profit margins of many mining operations, and the
increasing mineralogical complexity of mined ores, it has been neces-
sary to seek improvements in existing processes, and to control them
more efficiently. For example, much recent research effort has been
directed towards improving the fundamental knowledge of the chem-
istry of froth flotation, the dominant method of mineral concentration,
with a view to controlling the chemical environment more efficiently.
Similarly, continuing efforts have been made to control flotation and
other processes by computer, with good results in many cases.
This edition has been revised to incorporate the latest developments
in mineral process engineering. Chapter 1 has been completely
rewritten and includes examples of mill economics, as well as worked
examples. The increasing use of computers is reflected in Chapter 3,
which has been expanded to include worked examples and computer
methods. Useful microcomputer programs are listed in an Appendix.
Chapter 12 has also been thoroughly revised to reflect the latest
developments in flotation.
Discussions with many minerals engineers have aided preparation of
this edition, but I would particularly like to thank the following, who
have provided valuable advice and assistance:
Dr. Alan Bromley, Dr. Julie Holl, and Prof. Ken Hosking of
Camborne School of Mines; Prof. John Ralston of The South
Australian Institute of Technology; Palabora Mining Co., South
Africa; Mount Isa Mining Co., Australia.
Denver, Colorado B. A. WILLS
26 February 1987
vii
PREFACE TO THE THIRD EDITION
DURING the recent recession, which has had a great impact on the
minerals industry, the priority of many mining companies has been on
reducing costs, particularly energy costs, rather than on innovative
new techniques. Of major impact during this period, however, has
been the very rapid decline in cost, and the increase in reliability of
microprocessors, which has led to the increasing use of automation in
some milling processes.
This edition has been expanded to include an introduction to
automatic control and descriptions of some of the control strategies
which have been adopted on various concentrators. The section on
mass balancing has also been extended to include an introduction to
statistical methods, which are suited to evaluation by microcomputer.
The bibliography has been updated to include the latest references,
and the section on froth flotation has been revised and expanded.
I would like to thank all those people who have provided valuable
information and assistance in the preparation of this edition.
Particularly, I would like to thank the following:
Gosta Diehl and Teppo Meriluoto of Outokumpu Oy, for arranging
visits to various concentrators in Finland, and to the metallurgical
staff of Pyhasalmi, Vihanti and Vuonos mines for invaluable dis-
cussions.
Prof. Peter Linkson, and Dennis Nobbs of the University of Sydney,
Australia.
The metallurgical staff of Mount Isa Mines Ltd, Queensland,
Australia.
Peter Lean and the metallurgical staff of the Broken Hill mines,
New South Wales, Australia.
Dr. Don McKee of the Julius Kruttschnitt Mineral Research
Centre, Brisbane, Australia.
viii
PREFACE TO THIRD EDITION ix
Derek Ottley, Vice-President of Mineral Systems Inc., Stamford,
USA.
Dr. Bob Barley of Camborne School of Mines.
Sydney, Australia B. A. WiLLS
26 September 1983
PREFACE TO THE SECOND EDITION
ALTHOUGH this edition is again basically intended to satisfy the needs
of students in the minerals industry, it is also intended to provide
practising engineers with a valuable source of reference. In this respect
the bibliography has been considerably expanded and updated to
include the latest published works. The text has been extended
considerably to cover important subject areas more fully, and, where
appropriate, worked examples have been added. Two appendices
have been added for reference purposes.
I would like to thank the many people who have provided useful
criticism regarding the first edition, which has been valuable in the
preparation of this edition. Particularly, thanks are due to Mr. R. H.
Parker, Vice-Principal of the Camborne School of Mines, Mr. F. B.
Mitchell, formerly Vice-Principal and Head of Mineral Processing at
the CSM, and Mr. R. S. Shoemaker, Metallurgical Manager of
Bechtel Inc., San Francisco. I would also like to thank Prof. R. P.
King, of the University of the Witwatersrand, Johannesburg, for many
useful discussions.
Camborne, Cornwall B. A. WILLS
18 September 1980
x
PREFACE TO THE FIRST EDITION
THE main objective of this book is to provide students of mineral
processing, metallurgy, and mining with a review of the common
physical ore-processing techniques utilised in today's mining industry.
The need for such a book was highlighted during the preparation of the
degree course in Mineral Processing Technology at the Camborne
School of Mines. Although there are many excellent texts covering the
unit processes, most of these are now out of date, and many of the
methods described have been superseded by more modern techniques.
Descriptions of the treatments of specific ores have been deliberate-
ly restricted, except where to illustrate the applications of a particular
process. Methods of processing differ in detail from mine to mine,
even with very similar ores, and students should be strongly
encouraged to peruse the mining periodicals, which regularly detail
the treatment routes used on particular plants.
As in any book which deals with a very wide field, certain subject
areas will undoubtedly be open to debate, and I would greatly
appreciate comments and suggestions for improvement, which could
be incorporated into later editions.
I am indebted to many organisations and individuals who have
proved invaluable during the preparation of this book. The organisa-
tions who have provided illustrations for the text have been
acknowledged separately. I would like to express sincere thanks to my
friend and ex-colleague Dr. D. G. Osborne, without whose initial
encouragement the book would not have been written. Thanks are
also due to Mr. J. F. Turner and Mr. R. H. Parker, the Head of
Mineral Processing Technology, and the Vice-Principal, respectively,
of the Camborne School of Mines, for advice and encouragement.
Acknowledgement and thanks are especially due to the Series Editor,
Mr. D. W. Hopkins, of Swansea University, for invaluable discussions
and criticism during the preparation of the text. Finally I would like to
xi
Xll PREFACE TO THE FIRST EDITION
thank Mr. W. J. Watton for providing photographic services for the
preparation of the illustrations, and Mrs. H. A. Taylor and Miss K. E.
Bennett for patiently typing the draft manuscript.
Falmouth, Cornwall BARRY ALAN WILLS
9 March 1978
