Where did the gold and silver go? Answers to some of the problems of recovery and metallurgical accounting in gold and silver hydrometallurgical plants

CIM Bulletin, Vol. 75, No. 848, 1982

JOHN C. LORETTO, Metallurgical Consultant, H.A. Simons (Overseas) Ltd., Vancouver, B.C.

The paper identifies two of the main problems encountered in recent hydrometallurgical plants for the recovery of gold and silver: firstly, the plant recovery is lower than anticipated from the testwork; secondly, the metallurgical accounting figures cannot be reconciled. The principal reasons for the plant recovery being lower than the testwork are discussed, together with solutions that can minimize these problems both during the design stage and during the plant operation after the problems have manifest themselves. The reasons for the difficulties in metallurgical accounting are analyzed by reviewing the various components of the plant figures. Recommended solutions are given for minimizing this problem and the realities of obtaining accurate figures are discussed.

Mots Clés: Mineral processing, Gold, Silver, Hydrometallurgy, Metallurgical testwork, Grinding, Leaching, Plant losses.