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The current situation of rural domestic sewage discharge domestic sewage is an important part of rural pollution. Untreated domestic sewage is directly discharged, bringing various pollutants into the river, seriously polluting various water sources, causing eutrophication of water bodies and rapid reproduction of other plankton. The deterioration of water quality has caused a large number of fish and other organisms to die.

As far as a relatively perfect collection and disposal system of urban sewage is concerned, it is not feasible to centrally dispose domestic sewage in a large range in rural areas at this stage because of imperfect drainage network and weak economic foundation. Considering the dispersion and small quantity of rural domestic sewage, the application of small-scale integrated sewage treatment equipment is a more suitable treatment plan for China's national conditions.

The source of rural domestic sewage is mainly composed of the following parts: daily washing water; kitchen water; bathing and toilet sewage. In addition, it also involves other sewage discharge of water, such as aquaculture, animal husbandry, small workshops, etc. The high content of organic matter in rural domestic sewage mainly refers to the sewage produced in the life of rural residents. The main pollutants are nitrogen and phosphorus, bacteria and suspended solids. The concentration of ammonia nitrogen, total nitrogen, total phosphorus and other pollutants is generally higher.

In recent years, China has accelerated the establishment of new villages with a large total amount and increasing from time to time. Correspondingly, the consumption of rural areas and the discharge of domestic sewage are also increasing. Sewage is discharged without treatment, which aggravates the deterioration of open water and river network quality in rural areas and has a great adverse impact on the environment.