Method for treating high-concentration organic wastewater by anaerobic-aerobic deep coupling

Abstract

The invention relates to a method for treating high-concentration organic wastewater by anaerobic-aerobic deep coupling. The method comprises the following steps: introducing organic wastewater into an anaerobic reaction unit, and sufficiently mixing the organic wastewater with anaerobic granular sludge added into the anaerobic reaction unit in advance to perform anaerobic reaction; enabling anaerobic effluent obtained after anaerobic reaction to enter an aerobic reaction unit, and removing nitrogen through a synchronous nitrification and denitrification process; flowing part of effluent of the aerobic reaction unit back to the anaerobic reaction unit and fully diluting and mixing the part of effluent with the raw organic wastewater and granular sludge to carry out anaerobic reaction, andenabling the other part of effluent to enter a next treatment process or discharging the other part of effluent after reaching the standard. According to the invention, the anaerobic and aerobic reaction units are coupled to treat wastewater; anaerobic effluent enters the aerobic unit, the DO value in the water body of the aerobic unit is controlled, denitrification is effectively completed, thereflux ratio of the aerobic effluent is controlled, and the aerobic effluent returns to the anaerobic unit again, so that the ammonia nitrogen concentration in the anaerobic reactor is reduced, the activated sludge amount in the anaerobic reactor is ensured, and the anaerobic reaction efficiency is effectively improved.

Description

technical field [0001] The invention relates to a method for anaerobic-aerobic deep coupling treatment of high-concentration organic wastewater, which belongs to the technical field of sewage treatment. Background technique [0002] The treatment of high-concentration organic wastewater (such as printing and dyeing wastewater, food wastewater, beer production wastewater, etc.) is generally degraded by anaerobic reactors. The main factor affecting the efficiency of anaerobic reactions is the sludge properties in the anaerobic reactor, and the sludge properties are good The performance of the sludge is floc and granulation. When the sludge properties are good, the ability to adsorb pollutants is stronger, and the anaerobic reaction efficiency is also improved; body, unable to form granular sludge, and the reaction efficiency is relatively low. In addition, because organic wastewater often contains a large amount of nitrogen-containing substances, during the anaerobic degradat...

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Problems solved by technology

[0005] DO (dissolved oxygen in water) problem: the aerobic process generally requires a large amount of oxygen. For example, the dissolved oxygen in the aerobic section of the A / O process is controlled above 2.0mg / L, while in the anaerobic reaction, especially the methanogenic stage, due to Methanogens lack superoxide dismutase and are sensitive to O 2 very sensitive

If the effluent of the traditional aerobic biochemical process is directly recycled to the anaerobic unit, a large amount of O 2 It will interact with some active groups in the cells of methanogens, leading to the disintegration of important enzyme systems; at the same time, O 2 The superoxide anion free radicals produced will also cause lethal damage to cells, which will eventually lead to the failure of anaerobic reactions;

[0006] Nitrate nitrogen problem: It is generally believed that the anaerobic environment is a water body environment where there is no nitrate nitrogen or a very small amount, but most aerobic processes can only do a good job in the conversion process of ammonia nitrogen to nitrate nitrogen, but cannot complete the conversion process of nitrate nitrogen to nitrogen conversion

That is to say, once the aerobic effluent returns to the anaerobic unit, it will carry a large amount of nitrate nitrogen, directly destroying the anaerobic environment, so that the heterotrophic bacteria in the reactor become the dominant species, seriously affecting the anaerobic reaction process, and even failure of anaerobic reaction

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