METHOD OF DRYING SEWAGE SLUDGE Russian patent published in 2013 - IPC C02F11/14 C02F1/56 B01D21/01 

FIELD: chemistry.

SUBSTANCE: invention relates to methods of drying household and industrial sewage sludge and can be used in treating wastes and drying sludge at biological treatment facilities. The method of drying sewage sludge involves clarifying wastes that are premixed with excess sludge via reagent treatment thereof and subsequent mechanical drying of the sludge while adding a flocculant. The reagent used to clarify wastes is amino epichlorohydrin resin, which is obtained by reacting 25-40% aqueous dimethylamine solution heated to 40-49°C with epichlorohydrin, or by reacting epichlorohydrin heated to 40-49°C with 25-40% dimethylamine solution, with molar ratio of dimethylamine to epichlorohydrin of 1.0-1.1:1.0. Further, ethylenediamine or polyethylene polyamine are added to the reaction mixture in amount of 0.1-2.0 wt % of the total amount of dimethylamine and epichlorohydrin, and the mixture is held at 71-85°C for 1.5-2.0 hours. The amino epichlorohydrin resin is fed for treating wastes in an amount which provides residual content thereof in clarified wastes of not more than 0.24 mg/dm³. During mechanical drying, flocculant Praestol 853 BS is added to the sludge in amount of 3.2-5.0 kg/t dry substance. Mechanical drying of the sewage sludge is carried out by centrifuging.

EFFECT: high solid phase separation efficiency of the drying equipment, low moisture content of the sludge and high degree of clarification of wastes after primary settling tanks, as well as smaller area need to store the sludge.

2 cl, 1 dwg, 4 tbl, 3 ex