Patents Represented by Law Firm Andrus, Scealse, Starke & Sawall
  • Patent number: 5358544
    Abstract: Zinc is recovered from zinc sulphide material by introducing such material at a feed station into a molten copper sulphide matte which is circulated in a closed loop path through said feed station, a zinc recovery station and an oxidizing station. The matte is heated electrically directly by resistive heating. Oxygen in the absence of other gases is introduced at the oxidizing station. Sulphur dioxide is removed in a sulphuric acid plant. The method is operated to keep the activity of copper in the total matte at less than unit activity. Virtually zero gas emission is possible.
    Type: Grant
    Filed: May 10, 1993
    Date of Patent: October 25, 1994
    Assignee: The University of Birmingham
    Inventor: Noel A. Warner