A/O/A embranchment direct current biological denitrogenation method for treating coking waste water

Abstract

The invention provides a biological nitrogen removing method of A / O / A branched direct flow for treating coking wastewater, belonging to the technical field of environmental engineering. The biological nitrogen removing method mainly comprises: the pretreated coking wastewater entering a preposed anaerobic filter tank and proportionally distributing the water outlet by a water distributor, wherein a large amount of water enters an aeration tank for aerobic treatment and a little of water enters a carbon source supplementary dispenser for dispensing treatment, after filtering the water entering the aeration tank by a filter membrane assembly arranged in the aeration tank, pumping out the aerobic-treated water to enter an anoxybiotic filter tank, simultaneously receiving the little water from the water distributor by a carbon source dispenser and additionally dispensing and modifying depending on the carbon-nitrogen condition, wherein the little water is merged with the discharged water which is aerobic-treated in the aeration tank to enter the anoxybiotic filter tank for nitrogen removing treatment by denitrification. Compared with the prior art, the invention has the advantages of simplified operation, reduced cost and largely reduced floor space and energy consumption.

Description

technical field [0001] The invention belongs to the technical field of environmental engineering, and in particular relates to an A / O / A branch direct current biological denitrification method for treating coking wastewater. Background technique [0002] Coking wastewater is produced in the process of coking and gas production. The waste water discharge is large, the water quality composition is complex, there are many direct or indirect carcinogens, and it is difficult to biodegrade. In the process of biological treatment, the degradation of ammonia nitrogen often occurs after most of the organic pollutants are removed, so the biological denitrification of coking wastewater is a treatment technology for advanced treatment. At present, the biological denitrification of coking wastewater is mainly divided into two types according to the process flow: O / A (aerobic / anaerobic) and A / O (anaerobic / aerobic). Although the O / A process has local reflux, it is a direct-flow form from ...

AI Technical Summary

Problems solved by technology

Although the O / A process has local reflux, it is a straight-line form from the perspective of the whole system. The removal of most organic pollutants and the nitrification reaction of ammonia nitrogen into nitrate nitrogen are completed in the aerobic section. Therefore, the burden of the aerobic section Heavy, with high residual non-degradable COD (chemical oxygen demand); in the subsequent anaerobic stage, methanol needs to be added as a supplementary carbon source for denitrification and denitrification

The pre-anaerobic section of the A / O method improves the biochemical performance and does not require additional carbon sources. However, since the nitrification of biological denitrification must occur before denitrification, the whole system reflux process is adopted, and the reflux ratio is 2-4; This means that under the same residence time, the size of the structure must be enlarged by 3 to 5 times and the high energy consumption of the system

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