Treatment method and equipment for high-salt and alkali-weight-reduction waste water

Abstract

The invention relates to a treatment method and equipment for high-salt and alkali-weight-reduction waste water. The method comprises the following steps that the alkali-weight-reduction waste water is discharged to a regulating tank and enters an acidification tank after concentrated sulfuric acid is added; terephthalic acid is separated out as a white precipitate and settled at the bottom of the acidification tank; supernatant liquid of the acidification tank is mixed with solid slaked lime; effluent water enters a neutralization tank; the effluent water in the neutralization tank is diluted with dilution water, enters a distribution tank, and flows through an MBR (membrane bioreactor) aeration tank and an RO (reverse osmosis) system; fresh water from the RO system serves as the dilution water to enter the MBR aeration tank; and concentrated water meeting a discharge standard is discharged to a sewage treatment plant for centralized treatment. The treatment method and equipment for the high-salt and alkali-weight-reduction waste water integrates respective advantages of a membrane bioreator and reverse osmosis; sewage subjected to biochemical reaction treatment is filtered by a membrane; macromolecular substances such as suspended matters and colloids in the water are intercepted; the effluent water can meet the standards and be discharged directly or enter the next advanced treatment; and the treatment method and the device have the advantages that the floor area is small, the sludge amount is small, the operation is simple, and the control is easy.

Description

technical field [0001] The invention relates to a wastewater treatment method and device, in particular to a treatment method and equipment for high-salinity alkali reduction wastewater, belonging to the technical field of industrial wastewater treatment. Background technique [0002] Alkali reduction wastewater is produced during the alkali reduction process of polyester imitation silk. It mainly contains polyester hydrolyzate terephthalic acid, ethylene glycol, etc., and the content of terephthalic acid is as high as 75%. Alkali reduction wastewater not only has a high pH value (generally >12), but also has a high concentration of organic matter. In recent years, water-saving alkali weight reducers have been widely used. While reducing emissions, it also makes the COD of discharged wastewater Cr and higher conductivity. COD in wastewater discharged from alkali reduction process Cr It can be as high as 90,000 mg / L, and the conductivity is as high as 20,000-50,000 μS / c...

AI Technical Summary

Problems solved by technology

Due to the high content of refractory organic matter in this kind of wastewater, nanofiltration is performed directly after ultrafiltration, and the cost required for subsequent nanofiltration is relatively high

[0008] In addition, the above two methods are difficult to achieve the removal of salt

Images