Piggery waste water treatment method based on strong-thin shunt

Abstract

The invention provides a scale piggery waste water treatment method, which is characterized by separating the piggery waste water into supernatant (thin waste water) and bottom precipitates (strong waste water) through precipitation, carrying out anaerobic digestion on the strong waste water by adopting the intermediate-temperature or near-intermediate-temperature biogas fermentation process and producing biogas, using the biogas for generating power, using the waste heat generated during generating power or heat generated by combusting the biogas for raising or preserving temperature during strong waste water fermentation, ensuring the fermentation temperature to be the intermediate temperature or near-intermediate temperature, carrying out aerobic treatment on the thin waste water by adopting a sequencing batch reactor (SBR) or carrying out anaerobic digestion on the thin waste water by adopting the normal-temperature biogas fermentation process and producing the biogas, then carrying out aftertreatment on the effluent generated after anaerobic digestion of the thin waste water by adopting the natural treatment methods such as constructed wetland, oxidation ponds and the like, discharging the treated effluent up to the standard, using the effluent generated after anaerobic digestion of the strong waste water as the fertilizer or allowing the strong waste water to enter into a thin waste water treatment system to be treated together with the thin waste water. The method can improve the piggery waste water treatment efficiency and the biogas production efficiency.

Description

technical field [0001] The invention belongs to the field of environmental engineering wastewater treatment and is mainly used for the treatment of large-scale pig farm feces and sewage. Background technique [0002] For pig farm feces and sewage, the biogas fermentation process is generally used directly for anaerobic digestion treatment to remove most of the organic pollutants and at the same time recover energy—biogas. The effluent from anaerobic digestion of concentrated sewage is used as farmland fertilizer, or discharged up to standard after post-treatment. [0003] On the one hand, due to the large amount of flushing water in large-scale pig farms, the average flushing water for each pig reaches 15-25L, so that the concentration of fecal sewage in pig farms is not very high, TS is about 1%, and the total nitrogen (TN) content is about 0.1%. . Due to the large amount of water and the difficulty of heating and heat preservation, the normal temperature biogas fermentat...

AI Technical Summary

Problems solved by technology

Although direct aerobic treatment can achieve better organic pollutants and NH4+-N removal effect, due to the high concentration of pollutants in pig farm fecal sewage, it is generally necessary to dilute or Using a longer hydraulic retention time (HRT), both will increase the reactor volume and oxygen energy consumption

Dilution of raw sewage will also increase the cost due to dilution water