METHOD OF RECYCLING WASTE WATER Russian patent published in 2011 - IPC C02F9/04 C02F1/66 C02F1/06 C08G75/14 C02F101/30 C02F103/38 

FIELD: chemistry.

SUBSTANCE: method of recycling waste water formed at different steps of synthesis of polysulphide polymers involves mixing alkaline waste water, acidic waste water and/or diluted sulphuric acid, settling the mixed aqueous solution until formation of a two-phase dispersion system with precipitation of a suspension residue of a low-molecular polymer, separation of the residue from the aqueous salt solution and taking the residue for recycling. The remaining aqueous salt solution is evaporated to 0.5-0.6 of the volume and divided into a mixture of salts and concentrated waste water, which is recirculated to the sodium tetrasulphide synthesis step. The mixture of salts is divided into sodium thiosulphate and chloride and recycled separately. In the preferred version of the method, the alkaline waste water, acidic waste water and/or diluted sulphuric acid are mixed until an aqueous salt solution with pH=9.7-10.0 is obtained.

EFFECT: method provides a cheap and low-waste process of recycling waste water while improving environmental safety of producing polysulphide polymers.

2 cl, 1 dwg, 2 ex