Short-cut nitrification method for denitrification of corn starch wastewater by staged inflow a/o process

Abstract

The invention discloses a method for denitrification of cornstarch wastewater by a short-range nitrification segmented water inflow A / O process, which is suitable for denitrification treatment of cornstarch wastewater and similar industrial wastewater. The segmented water inflow A / O process has A / O pools connected in series, and an appropriate amount of high COD concentration water is introduced to increase the influent C / N, and water is continuously fed to the head of the A pool of each section of the A / O pool. in A 1 The head end of the pool enters low C / N water, at A 2 ~A n‑1 The head of the pool enters mixed water with suitable C / N, at A n Only appropriate amount of high COD concentration water is fed into the head end of the pool. The strategy of high ammonia, high temperature, high pH and low DO is used to start the short-cut nitrification, and then the long-term stable operation of the short-cut nitrification system is maintained by reasonable control of DO with the help of the temperature of the wastewater itself and the concentration of ammonia nitrogen. The invention can improve the water quality of the effluent water, simplify the operation control conditions, and achieve the goals of raising standards, saving energy and reducing consumption while giving full play to the advantages of the segmented water inlet A / O process.

Description

technical field [0001] The invention belongs to the technical field of sewage and wastewater treatment, and in particular relates to a method for denitrification of cornstarch wastewater by a short-range nitrification segmented influent anoxic / aerobic (A / O) process. Background technique [0002] my country is a big agricultural country with developed corn deep processing industry. Corn starch wastewater is a general term for the wastewater generated in each process in the process of producing starch from corn or starch sugar from starch. The production of corn starch and its products not only consumes a lot of water, but also has a large amount of sewage. The average effluent volume of producing 1 ton of corn starch is about 4 to 5 tons, and its wastewater has the characteristics of "4 high and 1 low", that is, chemical High oxygen demand (COD), high suspended solids, high total nitrogen, high total phosphorus, and low pH make terminal treatment very difficult. [0003] Si...

AI Technical Summary

Problems solved by technology

However, since the influent in the last stage of the staged influent A / O process usually only undergoes nitrification reaction without denitrification conditions, for the treatment of corn starch wastewater with high ammonia nitrogen, the effluent must contain a high concentration of nitrate nitrogen, which will affect the quality of the effluent water; If an anoxic stirring tank is added after the last A / O pool, good denitrification effect must also be obtained by adding carbon source

The method of adjusting the flow distribution ratio is used to optimize the water intake of each section. Although the denitrification effect of the system can be improved to a certain extent, for a reactor with a fixed structure, the water intake of each section is often adjusted according to the change of the C / N ratio of the feed water. The flow distribution ratio not only makes the operation process control very complicated, but also sometimes causes a large waste of nitrification and denitrification capacity, or affects the quality of effluent water due to insufficient nitrification and denitrification capacity.

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