Device and method for semi-nitrification/partial denitrification/anammox treatment of urban sewage with low carbon-to-nitrogen ratio

Abstract

The invention discloses a device and method for treating low-carbon-nitrogen-ratio urban sewage by virtue of half nitrification / partial denitrification / anaerobic ammonium oxidation, belonging to the field of sewage treatment. The device comprises an urban domestic sewage tank, a half nitrification reactor, a first intermediate water tank, a partial denitrification reactor, an external carbon source storage tank, a partial denitrification online monitoring and control system, a second intermediate water tank and an anaerobic ammonium oxidation reactor. The method comprises the following steps: firstly introducing domestic sewage into the half nitrification reactor, oxidizing part of ammonia nitrogen in the domestic sewage into nitrate nitrogen by virtue of aeration, introducing effluent into the partial denitrification reactor, reducing nitrate into nitrite by using a small amount of an external carbon source, and introducing the effluent into the anaerobic ammonium oxidation reactor for denitrification. By adopting the device and the method disclosed by the invention, stable and efficient denitrification of the low-carbon-nitrogen-ratio urban sewage can be achieved, and the problems that the existing short-cut nitrification nitrite accumulation of the urban domestic sewage is unstable and an existing anaerobic ammonium oxidation process is low in denitrification efficiency can be solved.

Description

Technical field [0001] The invention relates to a method for stably and efficiently treating urban sewage with a low carbon to nitrogen ratio, belonging to the technical field of sewage biological treatment. Specifically, urban domestic sewage first enters a semi-nitrification reactor to convert 50% to 70% of ammonia nitrogen into nitrate, and effluent enters Part of the denitrification reactor uses an external carbon source to convert nitrate into nitrite, and the effluent containing ammonia nitrogen and nitrite is removed by anaerobic ammonia oxidation. The invention utilizes partial denitrification to realize higher and stable nitrite accumulation, saves operating costs and expenses, and provides a low energy consumption, high efficiency and stable urban sewage denitrification method. Background technique [0002] In recent years, the degree of eutrophication in water bodies in my country has become increasingly serious, which not only affects the quality of drinking water, bu...

AI Technical Summary

Problems solved by technology

The short-cut nitrification process is mainly realized by controlling dissolved oxygen, temperature, pH or the inhibition of free ammonia, but the biggest problem facing short-cut nitrification is to obtain sufficient and stable nitrite accumulation

For urban domestic sewage with a low carbon-to-nitrogen ratio, short-cut nitrification at room temperature is difficult to maintain stability, resulting in low efficiency of subsequent anammox denitrification and complicated control process, which also limits the application of short-cut nitrification-anammox technology in cities sewage bottleneck

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