Self-adaptive variable-mode sewage treatment method for combined sewage system

Abstract

The invention discloses a self-adaptive variable-mode sewage treatment method for a combined sewage system. The method sequentially comprises the following steps: sewage enters an anaerobic section ofa biochemical tank after having underonge pretreatment of a pretreatment grid, sand setting and primary settling pretreatment, and is then sufficiently mixed with returned sludge; the effluent of theanaerobic section enters an anoxic section; the effluent of the anoxic section enters an aerobic section; the effluent of the aerobic section enters a self-adaptive section and a special device for the self-adaptive section, and mixed liquid from the self-adaptive section flows back to the anoxic tank; the effluent of the self-adaptive section enters a secondary sedimentation tank; sludge at thebottom of the secondary sedimentation tank enters a bypass treatment sludge relay tank and then flows back to the anaerobic tank; and the supernatant of the bypass sludge relay tank enters a bypass phosphorus removal tank, the effluent of the phosphorus removal tank is merged into the inflow of a sewage plant, and sludge discharged from the phosphorus removal tank enters a sludge treatment system.With the method of the invention, the buffer capacity of a sewage plant is improved, and a combined sewage treatment plant can still stably operate under the condition that flow is suddenly increasedby 2-3 times in rainy days and can achieve up-to-standard discharge.

Description

technical field [0001] The invention relates to the technical fields of environmental protection and water treatment, in particular to an adaptive variable-mode sewage treatment method for a terminal sewage treatment plant of a combined sewage system in a city. Background technique [0002] The way of collecting and transporting sewage and rainwater is called drainage system, which is generally divided into two basic forms: confluence system and diversion system. The separate drainage system is a system that discharges domestic sewage, industrial wastewater and rainwater in two or more independent channels; the combined drainage system mixes domestic sewage, industrial wastewater and rainwater in the same channel exhausted system. The difference between the two is whether the rainwater adopts independent pipes. At present, in cities and towns at home and abroad, it is common to adopt the confluence system and the diversion system. In some large cities, such as New York in ...

AI Technical Summary

Problems solved by technology

[0011] In view of actual needs, the technical purpose of the present invention is to provide a sewage treatment system and treatment method suitable for new construction, reconstruction and expansion of the terminal sewage treatment plant of the combined system, without greatly increasing land occupation and construction funds, and can effectively cope with the combined system. The problem of flow fluctuation and water quality fluctuation of the sewage treatment plant at the end of the system increases the comprehensive buffer capacity of the sewage treatment plant by 2-3 times, and ensures that the sewage treatment plant carries the peak flow rate of rainy days by more than 2-3 times in sunny days

Images