Глубокая очистка сточных вод трикотажного производства методом напорной флотации

Abstract

The article proposes a consistent technological scheme for deep wastewater treatment of knitted production both separately for the general runoff and according to the principle of combined flows, when wastewater from two or more production processes is sent to one stream. This approach allowed us, already at the stage of averaging wastewater from selected technological processes, to obtain minimum concentrations of major pollutants in the average (mixed) flow of this stream and thereby ensure their effective treatment in the proposed facilities. This approach allowed us, already at the stage of averaging wastewater from selected technological processes, to obtain minimum concentrations of major pollutants in the average (mixed) flow of this stream and thereby ensure their effective treatment in the proposed facilities. Bleaching (up to 85%) of pre-averaged industrial effluents and removal of the main part of suspended solids from them (up to 84%) was initially carried out in thin-layer sedimentation tanks with the use of aluminum sulfate or iron coagulants in combination with polyacrylamide flocculant (PAF). After reagent sedimentation, wastewater had fairly high residual concentrations for the main pollutants (in terms of color intensity – 1:42, -1:47, for suspended solids 43…46 mg/l, for BOD_full –132…135 mg O₂/l, for COD-355…363 mg/l and especially for surfactants – 44…45 mg/l) and needed deep cleaning, which was carried out by pressure flotation. After pressure flotation, the mixed effluents of the proposed two streams and the total effluent were purified to the extent that they could be discharged into the city sewer. It follows from the above that in the proposed scheme, pressure flotation can be used in the final stage of wastewater treatment of knitted production. After pressure flotation, the mixed effluents of the proposed two streams and the total effluent were purified to the extent that they could be discharged into the city sewer. It follows from the above that in the proposed scheme, pressure flotation can be used in the final stage of wastewater treatment of knitted production.