method for purifying wet gas containing sulphur, halogens and arsenic obtained from treatment pirometallurgico materials sulfurici

摘要

The invention comprises a method of wet-cleaning gases containing sulfur dioxide, halogens together with arsenic and/or arsenic compounds obtained in a pyrometallurgical treatment of sulfidic materials. The gases are washed in a diluted sulfuric acid circulating in a closed circuit, from which arsenic is recovered. The gases are then cooled to water condensation whereby the halogens are substantially completely taken up in said condensate and separated. The separated condensate is then discharged to a recipient after precipitation of residual arsenic and neutralization.