TECHNOLOGY OF CYCLIC USE OF ACID EFFLUENTS Russian patent published in 2025 - IPC C02F9/00 C02F1/46 C02F1/28 B01D53/14 

FIELD: waste water treatment.

SUBSTANCE: acid effluents discharged from the etching line enter the acid effluent control basin. Spent acid liquid discharged from the etching line is supplied to the acid regeneration reaction furnace for pyrohydrolysis reaction, and the formed flue gas containing acid components is supplied to the acid regeneration absorption device. Acid effluents from the acid effluent control basin after preliminary treatment enter intermediate basin 1. From intermediate basin 1 the effluents are supplied to the electric adsorption device of the first degree for treatment to obtain concentrated water of the first degree and produced water of the first degree. Concentrated water of the first degree as the absorbing liquid of the regenerated acid enters the absorption device for acid regeneration. Flue gas containing acid components is subjected to spray absorption with formation of regenerated acid, which enters the etching line for recirculation. Produced water of the first degree enters the electric adsorption device of the second degree for treatment to obtain concentrated water of the second degree and produced water of the second degree. Concentrated water of the second degree uses excess pressure to enter intermediate basin 1. Produced water of the second degree enters intermediate basin 2. Produced water of the second degree from intermediate basin 2 after treatment in the system of treatment of alkaline waste water is reused, and/or the produced water of the second degree is mixed with new acid and it enters the etching line as an additional acid.

EFFECT: reduced consumption of reagents and amount of sediment, avoiding increase in content of salts and providing better quality of water.

10 cl, 1 dwg