Treatment of base metal smelter slag

Abstract

A process for treating base metal smelter slag containing from about 20 to about 60 percent by weight iron and at least one further metal selected from the group consisting of nickel, copper and cobalt comprises mixing base metal smelter slag with calcium sulphate and carbon and melting the resultant mixture to produce a metallic sulphide matte containing substantially all the further metal or metals and a secondary slag substantially free of the further metal or metals suitable for use as a cement.

Description

Claims

1. A process for treating base metal smelter slag containing from about 20 to about 60 percent by weight iron and at least one further metal selected from the group consisting of nickel, copper and cobalt, the process comprising mixing base metal smelter slag with calcium sulphate and carbon and melting the resultant mixture to produce a metallic sulphide matte containing substantially all said further metal or metals and a secondary slag substantially free of said further metal or metals suitable for use as a cement.

2. A process according to claim 1 wherein the base metal smelter slag is mixed with from about 10 to about 60 percent by weight calcium sulphate and from about 2 to about 10 percent by weight carbon relative to the weight of the base metal smelter slag.