Septic tank and sewage treatment method using pretreatment and biological contact

Abstract

The invention discloses a septic tank and sewage treatment method using pretreatment and biological contact in the technical field of treatment of domestic sewage. The septic tank which adopts pretreatment and biological contact includes a pretreatment aeration pool, a pretreatment sedimentation pool, an anaerobic fermentation pool, a biological contact oxidation pool, a secondary sedimentation pool and a blower, wherein a water inlet pipe is arranged on the pretreatment aeration pool, a first overflow plate is arranged between the pretreatment sedimentation pool and the pretreatment aerationpool, and the anaerobic fermentation pool is a sealed cavity. Sewage is pretreated under the condition of aeration firstly, organic matter and suspended matter in the sewage are adsorbed by sludge, and therefore the obtained sewage has a low carbon-nitrogen ratio; sedimentation of the sludge is performed in the pretreatment sedimentation pool, only the liquid is discharged, and solid matter whichcarries parasite eggs is left, so that anaerobic sterilization and egg killing are achieved; denitrification and phosphorus removal are performed, so that organic matter is reduced, and the sewage ispurified effectively; finally resting sedimentation is performed so that excessive SS which is caused by biofilm falling off and aeration agitation can be avoided; therefore, the method has a good treatment effect on organic matter, nitrogen, phosphorus and other matter.

Description

technical field [0001] The invention relates to the technical field of domestic sewage treatment, in particular to a septic tank and sewage treatment method using pretreatment and biological contact. Background technique [0002] The septic tank is a local sewage treatment facility attached to the building, which belongs to the primary transitional domestic sewage treatment structure. The three-compartment septic tank is usually composed of three compartments sealed septic tanks connected by two sewage pipes. According to the main functions of the three pools, they can be named as interception sedimentation and fermentation tank, re-fermentation tank and dung storage tank. The traditional three-compartment septic tank achieves the purpose of removing pathogenic bacteria and degrading some organic matter through physical and biochemical processes such as interception, sedimentation, and oxidative decomposition. Under normal circumstances, after 12-24 hours of sedimentation ...

AI Technical Summary

Problems solved by technology

Under normal circumstances, after 12-24 hours of sedimentation in the septic tank, BOD5 can remove about 20%-30% of sewage with an original organic concentration of 100-400mg / L, and the removal effect on N and P is poor. , the content of organic matter, N, and P in the septic tank effluent is still high

In many rural areas, the three-compartment septic tank is the only treatment facility before domestic sewage is discharged directly. The treatment effect of the septic tank on domestic sewage is poor. Pollution, with the increasing requirements of environmental protection, it is necessary to transform the three-compartment septic tank

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