FIELD: waste water treatment.
SUBSTANCE: invention relates to utilizing effluents formed at pig-breeding complexes and farms and can be used in agriculture to treat liquid waste from pig-breeding complexes and farms to be used as fertilizers and for irrigation agricultural areas. In particular, alkaline coagulator is first added to calcium carbide slurry to pH 10-11.5, after which acidification reagent is added to pH 6.5-8.5 followed by separation of precipitate, said acidification reagent being phosphoric acid production waste: calcium sulfate dihydrate suspension. Doses of reagents are the following: calcium sulfate dihydrate suspension (calculated as P2O5) 8.0-20.0 g/dm3 and calcium carbide slurry (as CaO) 1.0-3.0 g/dm3. Method allows reagent preparation procedure to be simplified and expenses on treatment of raw material before its use in agriculture to be reduced. Moreover, soil-conservation value of produced fractions is improved while settling time is shortened. Implementation of the method not only allows solving problem of utilizing phosphoric acid and acetylene waste but also obtaining fertilizer of higher chemical value as compared to methods earlier proposed.
EFFECT: enhanced organic fertilizer manufacture efficiency and improved its value.
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