Urban sewage treatment process suitable for quasi IV-class water standards

Abstract

The invention discloses an urban sewage treatment process suitable for quasi IV-class water standards. The urban sewage treatment process comprises a first-stage pretreatment system, a second-stage biochemical treatment system and a third-stage deep treatment system. High-precision hydraulic cyclone desanding is adopted in the first-stage pretreatment system. The second-stage biochemical system adopts a multi-stage multi-section A / O process; a biological tank is sequentially arranged into a first-stage anaerobic / aerobic zone and a multi-stage anoxic / aerobic zone, and internal reflux is avoided. Effluent of the biological tank enters a secondary sedimentation tank, part of sludge in the secondary sedimentation tank flows back to an anaerobic zone of the biological tank, and residual sludgeenters a sludge system for concentration and dehydration treatment. Effluent of the secondary sedimentation tank passes through a drum micro-filter, and finally effluent is disinfected, can be discharged outside after reaching the quasi IV-class water standards, and can also be used for reuse such as site washing, greening and the like. The sewage treatment process provided by the invention has good effects of removing organic matters and SS and removing nitrogen and phosphorus, and can stably realize the quasi IV-class effluent standards.

Description

technical field [0001] The invention relates to the field of sewage treatment, and specifically relates to a high-efficiency and energy-saving process method oriented to quasi-category IV discharge standards. Background technique [0002] With the increasingly stringent environmental management, although "Class A" is the highest requirement in the national standard, in actual projects, a wave of water projects with "quasi-IV water" as the discharge standard has emerged. Beijing, Tianjin, Guangdong China, Jiangsu, Zhejiang and other regions have successively released local standards, and have successively carried out related work to raise the standard of "quasi-IV water". [0003] Most of the existing sewage treatment processes are designed for the parameters of the first-level A. In order to meet the requirements of quasi-IV water, they are generally used after the second-level biological treatment, and then the third-level biological treatment. The biofilm method or denitri...

AI Technical Summary

Problems solved by technology

This new technology provides a high-efficiency and energy-saving urban sewage treatment process oriented to quasi-IV discharge standards to overcome the defects of low total nitrogen and total phosphorus removal rates and insufficient carbon sources in the existing sewage treatment process, making urban sewage treatment more efficient. Economical, efficient and stable

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