Efficient denitrification, dephosphorization, denitrification and phosphorus resource recycling process for urban sewage

Abstract

The invention discloses an efficient denitrification, dephosphorization, denitrification and phosphorus resource recycling process for urban sewage. The process comprises the following steps of: adding the sewage into an anaerobic pond; adding the sewage into a first sedimentation basin for sludge and water separation, adding sludge into an oxygen-poor pond across a nitrification pond, adding a part of supernatant into an induced crystallization reactor for dephosphorization, adding the part of dephosphorized supernatant into the nitrification pond, directly adding the other part of supernatant into the nitrification pond and converting ammonia nitrogen in the supernatant into nitrate; adding the sewage in the nitrification pond into a second sedimentation basin for sludge and water separation, adding the supernatant into the oxygen-poor pond for finishing phosphorus absorption and denitrification, making a part of sludge flow back into the nitrification pond and discharging the residual sludge; and adding the sewage into an aeration basin from the oxygen-poor pond and adding into a final clarifier from the aeration basin for sludge and water separation, discharging the supernatant, making a part of sludge flow back into the anaerobic pond and discharging the residual sludge. After being treated by the process, discharged water directly reach a first grade A standard of a pollutant discharge standard for municipal sewage treatment plants, and has extremely high dephosphorization and denitrification efficiencies.

Description

technical field [0001] The invention relates to a process for treating sewage, in particular to a process for denitrifying, dephosphorizing, denitrifying and highly efficient recovery of phosphorus resources in urban sewage. Background technique [0002] At present, my country's water pollution problem is becoming more and more serious, and the total nitrogen and total phosphorus of lakes are seriously exceeded, which leads to the prominent problem of eutrophication. Most of the existing sewage treatment plants adopt the traditional biological nitrogen and phosphorus removal process, and it is difficult to achieve simultaneous improvement of nitrogen and phosphorus removal efficiency. In view of the problem that the nitrogen and phosphorus removal efficiency cannot be further improved, foreign scholars have proposed a new type of biological treatment process, such as the double sludge denitrification process for phosphorus removal. This process solves the problems of carbon...

AI Technical Summary

Problems solved by technology

However, the dual-sludge denitrification phosphorus removal process is faced with the fact that the ratio of nitrogen and phosphorus in the influent water is difficult to meet the requirements of anoxic phosphorus uptake in practical applications.

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