Denitrification treatment method for industrial wastewater

Abstract

The invention discloses a denitrification treatment method for industrial wastewater. The process flow is sequentially provided with an adsorption unit, an anoxic unit, an anaerobic unit, an anoxic / aerobic unit, an aerobic unit and an MBR membrane tank from front to back. The denitrification treatment method comprises the following steps of: (1) sludge of the anaerobic unit flows back to the frontend and mixing with inlet water to enter the adsorption unit for pretreatment; (2) MBR membrane tank mixed liquid flows back to the anoxic unit for denitrification; (3) the anaerobic unit hydrolyzesand acidifies remain refractory organic matters and ammonifies organic nitrogen in wastewater at the same time; (4) the anoxic / aerobic unit carries out simultaneous nitrification and denitrification;and (5) the aerobic unit and the MBR membrane tank carry out oxidation decomposition and nitration reaction on residual organic matters in the wastewater. By adopting the process method, the problem that the COD and total nitrogen in effluent of the industrial wastewater treated by the traditional secondary biochemical process are difficult in reaching the standard can be solved, the organic matters in the raw water are fully utilized for denitrification, and the operation cost is saved.

Description

technical field [0001] The invention belongs to the field of wastewater treatment, and in particular relates to a denitrification treatment method for industrial wastewater. Background technique [0002] Industrial wastewater is wastewater and waste liquid produced in industrial production. It has various types and complex components. For example, coking wastewater and synthetic pharmaceutical wastewater not only contain high COD and total nitrogen, but also contain high levels of toxic substances and refractory organic matter in wastewater. The current denitrification treatment process of industrial wastewater is mainly based on AO, AAO, AOO, AOAO and other methods. The ammonia nitrogen in the wastewater is converted into nitrate nitrogen through nitrification reaction under aerobic conditions, and the generated nitrate nitrogen is under anoxic conditions. The easily degradable organic matter is reduced to nitrogen removal through denitrification reaction. In the case of or...

AI Technical Summary

Problems solved by technology

For the traditional one-stage AO denitrification treatment process (AO, AOO), because the industrial wastewater contains more toxic substances, it will have a certain inhibitory effect on the biological denitrification reaction and affect the denitrification effect, and because the industrial wastewater is biodegradable Insufficient available carbon source in the denitrification process will affect the denitrification effect

In addition, due to the high concentration of COD in industrial wastewater, the organic load of the aerobic unit in the primary AO process (AO, AAO) is high, and the nitrifying bacteria are inhibited, which affects the effect of nitrification reaction and makes it difficult for the effluent ammonia nitrogen and total nitrogen to meet the standards.

For the secondary AO denitrification process (AOAO), the organic carbon source in the wastewater is mainly removed in the front-stage aerobic process, resulting in waste of carbon source and high energy consumption in industrial operation, although sufficient nitrification can be carried out in the post-stage aerobic unit reaction, but the denitrification process lacks carbon sources, and additional carbon sources need to be added, resulting in increased operating costs

At the same time, AO, AOO, and AOAO processes cannot achieve a good removal effect on organic nitrogen in wastewater

Therefore, the traditional denitrification treatment process is difficult to meet the latest emission standards, especially in terms of total nitrogen

[0003] Therefore, the existing industrial wastewater denitrification treatment technology needs to be improved

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