Sewage treatment method capable of sludge quantitative reduction

Abstract

The invention discloses a sewage treatment method capable of sludge quantitative reduction. According to the invention, raw water enters into a physicochemical section at first, treated raw water is discharged into a biochemical tank for biochemical treatment, treated waste water enters into a secondary sedimentation tank, is settled and then is discharged after the waste water reaches the standard, one part of sludge is extracted from the secondary sedimentation tank and is allowed to reflow into the biochemical tank, the other part of sludge is sent to an intermediate microbial cultivation tank for culture of indigenous microorganism, one part of the cultivated sludge is sent to the front of the biochemical tank, and the other part of the cultivated sludge is sent to the physicochemical section for spray deodorization of the raw water in the physicochemical section; effluent of the secondary sedimentation tank enters into a dephosphorization tank for post chemical dephosphorization, and effluent after dephosphorization is discharged after reaching the standard; all sludge in the secondary sedimentation tank is discharged into a sludge dehydration center after a certain period, supernatant obtained after dehydration reflows to the front of the biochemical tank, and dried sludge is delivered out for landfilling or brickmaking. The method enables sludge quantitative reduction of a system to be realized in the treating process of sewage, an average annual sludge output of the system being 15 to 20% of that of an original system. Deodorization is carried out in the phase of pretreatment, thereby improving surrounding environments.

Description

[0001] technical field [0002] The invention relates to a sewage treatment method, in particular to a sewage treatment method with a sludge reduction function, which can reduce the amount of excess sludge in the sewage treatment process. Background technique [0003] Most of the sewage treatment in our country adopts the activated sludge method, which has the advantages of low capital investment and good treatment effect, but it has always had one of the biggest drawbacks, that is, a large amount of excess sludge will be generated during the operation process. Excess sludge usually contains a considerable amount of toxic and harmful substances and unstabilized organic matter. If not properly treated and disposed of, it will cause direct or potential pollution to the environment. In the traditional activated sludge method, every 1kgBOD degraded 5 (biochemical Oxygen Demand, five-day biochemical oxygen demand) will produce about 15-100 L of excess sludge, and the cost of tre...

AI Technical Summary

Problems solved by technology

However, the above-mentioned technologies generally have disadvantages such as immature technology, high operating costs, and large investment.

The technology of ultrasonic treatment of sludge is currently in the stage of laboratory research in China, and has not been applied to engineering.

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