METHOD FOR REPROCESSING OF CLAYEY SALT MUD OF CHLORIDE PRODUCTION Russian patent published in 2003 - IPC

FIELD: nonferrous metallurgy. SUBSTANCE: method involves washing off mud with water for removal of chlorides and saline solutions; converting gold into chloride solution and providing gold sorption; washing off mud for removal of chlorides until residual chlorine content is 3-7%; providing saturation, drying, sintering and thermal processing of washed off mud while continuously heating to temperature of 1,000-1150 C at oxygen content in thermal processing gases within the range of 13-16% and keeping at said temperature until resultant processed material has chlorine content of no more than 0.3%; reprocessing thermal processing gaseous phase by providing cooling, condensing and absorptive washing with following separation of solid chloride condensate and absorptive washing pulp; performing gold sorption from said pulp. Washed off mud is saturated by settling and/or filtering and saturated washed off mud is dried until residual moisture content is within the range of 25-30%. Sintering of saturated and dried mud is provided by lumping and/or briquetting, and/or forming. When lumping process is performed, drying and lumping processes are effectuated in single unit. Before sorption process, absorbed pulp is subjected to filtering for separating silver- bearing cake. Method is used for extracting gold and silver from clayey salt separated upon reprocessing of alkaline and alkaline-earth metal chloride raw materials, in particular, sylvinite, carnallite, and hallite. Solid residue in the form of burnt lumped material is used in manufacture of construction materials. EFFECT: increased efficiency and improved quality of gold and silver extraction in gaseous phase. 6 cl, 3 tbl, 6 ex