METHOD OF PROCESSING ALUMINUM-CONTAINING RAW MATERIAL Russian patent published in 2003 - IPC

FIELD: processing aluminum-containing raw materials by sintering; production of aluminum hydroxide of pseudoboehmite structure. SUBSTANCE: includes sintering with limestone and alkalicontaining material forming gaseous products and sinter, leaching sinter at obtaining aluminate solution, desiliconization of aluminate solution, dilution of desiliconized solution by aqueous solution, carbonization of diluted solution, separation of sediment formed during carbonization from carbonate solution and flushing the sediment obtaining pseudoboehmite and industrial water. Used as aqueous solution for dilution is carbonate solution; dilution is performed till molar ratio of carbonate alkali to common alkali is equal to 0.15 to 0.6; carbonization is performed with gaseous sintering products at temperature of 10 to 50 C and consumption of CO₂/Al₂O₃ equal to 1.5 cu dm/g; flushing the sediment is performed at temperature of 40 to 100 C; carbonates of alkaline metals are extracted from carbonate solution and industrial water. Soda is used as alkali- containing material at sintering. Aqueous solution for dilution is preliminarily saturated with gaseous sintering products. Molar fraction of potassium is sum of sodium and potassium in solution ranges from 0.2 to 0.8 before carbonization. Proposed method makes it possible to recover liquid waste. EFFECT: enhanced efficiency. 4 cl, 4 tbl, 6 ex