BIOX~(~R) Process - The Sao Bento Experience

摘要

The oxidation capacity of the Sao Bento plant was successfully increased by minor modifications to the pressure oxidation circuit and by converting an existing tank into a third BIOX~(~R) reactor at a relatively small capital expenditure. The new BIOX~(~R) reactor had a pay back period of only four months. In June 1998 the BIOX~(~R) plant oxidized a record 300 tons of pyritic sulphur. This corresponds to 15% of the sulphide sulphur content of the total concentrate tonnage treated. The new BIOX~(~R) tank oxidized 69 tons of pyritic sulphur or 23% of the total BIOX~(~R) production. The optimization program in the plant has now been completed and throughput rates of 500 000 tons per year of sulphide ore are being achieved. This equates to an annual gold production of 4000 Kg. The mine produced its one-millionth ounces of gold in July 1998.