| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for purifying slag, which reduces impurity elements such as zinc, lead and arsenic contained in slag in a smelting furnace for smelting copper. <P>SOLUTION: This purification method comprises the steps of: adding metallic copper to molten slag containing zinc, lead and arsenic, which has been obtained by separating a matte phase from the slag in the smelting furnace in a copper smelting process using a copper sulfide concentrate as a raw material; stirring the slag at 1,150 to 1,450°C, while controlling a partial pressure of oxygen in the slag into a range expressed by the following expression to vaporize and separate zinc and lead from the slag and simultaneously form a slag phase and a metallic copper phase containing arsenic; and then, separating the metallic copper phase from the slag. The expression is given by: 10<SP>-8.5</SP>>Po<SB>2</SB>>10<SP>-11.0</SP>, wherein Po<SB>2</SB>represents the partial pressure of oxygen in the slag by an atm unit in terms of 1,400°C. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
