Cotreatment of sewage and steelworks wastes

摘要

Steelworks dusts or sludge is mixed into sewage preferably in the presence of a flocculating agent to provide a rapid separation of a clear effluent and a sludge which is dewatered and dried to form a solid material adapted to entrap harmful materials in the sewage such as heavy metals, pathogens and organic chemicals. The solid material is supplied to a smelt reduction furnace from which molten iron is recovered and a hot gas discharge is provided from which recovery of zinc and other materials may be achieved, other waste material being removed as a slag.