Domestic sewage is the wastewater discharged from the daily life of residents, mainly from residential buildings and public buildings, such as residences, institutions, schools, hospitals, shops, public places and toilets of industrial enterprises. The pollutants contained in domestic sewage are mainly organic matter (such as protein, carbohydrates, fat, urea, ammonia nitrogen, etc.) and a large number of pathogenic microorganisms (such as parasite eggs and intestinal infectious viruses). The organic matter in domestic sewage is extremely unstable and easy to decay and produce foul odors. Bacteria and pathogens multiply in large numbers by feeding on organic matter in domestic sewage, which can lead to the spread of infectious diseases.

Membrane bioreactor (MBR) is a new and efficient wastewater treatment and reuse process that combines biodegradation with efficient membrane separation technology. It is the use of membrane separation equipment to intercept the activated sludge and macromolecular substances in the biochemical reaction tank, save the secondary sedimentation tank, mechanical filtration, and improve the separation efficiency of slurry and water; Through the efficient interception effect of the membrane, the suspended solids are completely trapped in the biological reaction tank, the effluent quality is improved, and the concentration of activated sludge is greatly increased, and the hydraulic retention time (HRT) and sludge retention time (SRT) can be controlled separately, which greatly improves the biochemical treatment efficiency and reduces the ratio of F/M. In this case, the refractory substances continue to react and degrade in the reactor, which helps to reduce the output of residual sludge (and even achieve zero sludge discharge) and reduce sludge treatment costs.

The core of domestic sewage treatment is the biochemical part, and the main process includes biological contact oxidation method and MBR membrane method.

The biological contact oxidation method is a kind of aerobic biofilm method, which is improved and evolved from the contact aeration method on the basis of the biological filter, so it is also called "immersion filter method", "contact aeration method" and "submerged biofilm method".

The process flow is as follows:

Domestic sewage treatment, sewage treatment, wastewater treatment, integrated sewage treatment equipment, industrial wastewater treatment, reclaimed water reuse