Abstract: Impurity streams generated during the metallurgy of copper are hydrometallurgically processed at ambient pressure for recovery of primary values in an energy-efficient manner and with the capture and conversion of metallic impurities to states that are acceptable for disposal into the environment. Hallmark features of the various embodiments of this invention include the water leach of flue dust, a controlled acid leach stage in which metal species are solubilized, the extraction of copper as a sulfide, and the ability to operate the various process stages at essentially ambient pressure.

Abstract: Impurity streams generated during the pyrometallurgy of copper are hydrometallurgically processed at ambient pressure for recovery of primary values in an energy-efficient manner and with the capture and conversion of metallic impurities to states that are acceptable for disposal into the environment. Hallmark features of the various embodiments of this invention include the water leach of flue dust, the extraction of water-soluble copper as a separate product, a controlled acid leach stage in which bismuth is solubilized, the return of copper to the smelting process as a sulfide, the ability to operate the various process stages at essentially ambient pressure, and the gradual reduction in temperature over the course of the process without the use of indirect heating or cooling operations.