Patent ID: 6395060
Filing Date: 2002-05-28
Classification: C22B,Y02P,Y10S

Abstract:
A method of processing flue dust that contains one or more compounds from a first group consisting of zinc, lead and cadmium compounds, and contains one or more compounds from a second group consisting of iron, silicon, calcium, magnesium and aluminum compounds, the method comprising mixing the flue dust with a carbonaceous material, introducing the mixture of flue dust and carbonaceous material into a heating vessel, heating the vessel from a primary heating source, combusting the carbonaceous material within the vessel to further heat the flue dust, wherein the heat from the primary source and the heat from the combustion of the carbonaceous material cause a substantial portion of the compounds from the first group to become gas-borne while retaining a substantial portion of the compounds of the second group in a non-gas-borne condition, wherein the iron content of the gas-borne compounds is less than 1 percent by weight, and separating the gas-borne compounds from the non-gas-borne compounds.