Method for starting A2N two-stage SBR denitrifying phosphorus removal

Abstract

The invention discloses a method for starting A2N two-stage SBR denitrifying phosphorus removal, and belongs to the field of municipal sewage treatment. The invention aims to solve the problems that in the starting process of denitrifying phosphorus removal in the prior art, the growth rate of denitrifying phosphorus removal bacteria is low, and has poor competitive power as compared with aerobic phosphorus-accumulating bacteria, so that nitrate nitrogen is required to be added for enrichment, the starting is difficult, and the cost is increased; and that direct starting of denitrifying phosphorus removal using domestic wastewater requires long acclimation time, and the sludge concentration is greatly reduced due to elutriation. According to the invention, aerobic phosphorus-accumulating bacteria and nitrifying bacteria are respectively cultivated and mixed uniformly according to the mass ratio of 2: 1; the aerobic running strengthens the nitrification-denitrification effect until the oxidation rate of ammonia nitrogen reaches more than 90%, the removal ratio of COD reaches more than 75%, 1 / 3 of the volume of the sludge is separated to enter into another reactor. The original reactor can be used as a denitrifying phosphorus removal reactor, and the two SBR reactors are operated in an A2N mode. By using the method provided by the invention, the starting speed of denitrifying phosphorus removal using actual domestic wastewater is fast, the sludge concentration after starting is high, and nitrate nitrogen is not required to be added during the starting period.

Description

technical field [0001] The invention relates to a method for starting A2N double-stage SBR denitrification and dephosphorization, which belongs to the field of urban sewage treatment and resource utilization. Background technique [0002] Nitrogen and phosphorus are the main factors causing lake eutrophication. At present, the main goal of sewage treatment in my country is still COD. The removal of nitrogen and phosphorus is not enough attention. The concentration of ammonia nitrogen in the actual domestic sewage of the community is 50~70mg / L, and the concentration of phosphorus is 6 ~7mg / L, due to the different sludge ages of nitrifying bacteria and aerobic phosphorus accumulating bacteria, limited COD in sewage, etc., the removal of nitrogen and phosphorus cannot be taken into account. Sewage plants usually operate in the way of biological denitrification and chemical phosphorus removal, which increases the cost of sewage treatment, and the chemical agents added will have a...

AI Technical Summary

Problems solved by technology

Use actual domestic sewage to directly start denitrification and phosphorus removal, with long start-up period and low sludge concentration after start-up

This is not conducive to engineering applications

Moreover, the conventional A2N two-stage SBR process can only screen denitrifying phosphorus accumulating bacteria, and is not easy to enrich denitrifying phosphorus accumulating bacteria: in the early stage, mature aerobic phosphorus removal sludge was obtained in the first SBR reactor, and the second SBR reaction After the mature nitrifying sludge is obtained in the first SBR reactor, it is necessary to add nitrate nitrogen to the first SBR reactor to induce the transformation of aerobic phosphorus accumulating bacteria into denitrifying phosphorus accumulating bacteria. Only by connecting the second SBR reactor and running it in A2N mode can the startup be successful quickly

This increases the complexity and cost of the process

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