METHOD OF SEWAGE TREATMENT FROM HEAVY METALS Russian patent published in 1995 - IPC

FIELD: sewage treatment. SUBSTANCE: method involves the use of supernatant after microbial coal processing as a sorbent. Sorbent oxidized coal contains active carboxy-groups 4 mg-equiv./g (not less), capacity of cationic exchange is 103-148 mg-equiv./100 g and content of immobilized microorganisms is 5.5-10.4 billion/g. Use of sorbent at concentration 100-250 g/1 g metal ensures to decrease the residual concentration of heavy metal in sewage up to permissible concentrations. The source of microorganisms: a mixture of microbe cultures Acinetobacter coaleoacetficus, Pseudomonas denitrificans, P. louda at the weight ratio 1:1:1. In the immobilization process phosphate fertilizer is added firstly to coal (1 g per 50 g coal), and after stirring slaked lime is added up to pH 7. EFFECT: improved method of sewage treatment. 2 cl, 3 tbl