A two-stage a/o enhanced biological denitrification process for coking wastewater by combining mbbr and activated sludge process

Abstract

The invention discloses a two-stage A / O enhanced biological denitrification process for coking wastewater combined with MBBR and activated sludge process. The process uses suspended fillers to be easily fluidized in the reaction tank to form MBBR, and then forms a composite system with activated sludge. The biofilm on the surface of the suspended packing has the functions of nitrification and simultaneous nitrification or denitrification, and the system has a stronger denitrification function and anti-shock load capacity; the fluidization of the suspended packing in the O tank can improve the oxygenation efficiency, and the aeration rate is reduced by about 20% , saving energy consumption; the Fenton reaction tank between the two-stage A / O can improve the biodegradability of the first-stage A / O effluent, reduce the amount of additional carbon source, and reduce the operating cost of the biochemical section. This process transforms the traditional activated sludge reaction tank. After adding suspended fillers, a composite system of MBBR and activated sludge process can be formed, which strengthens the system's denitrification function and impact load resistance, and is suitable for the existing coking wastewater treatment. Upgrading and renovation of facilities.

Description

technical field [0001] The invention belongs to the field of refractory wastewater treatment, and in particular relates to a two-stage A / O (anoxic / aerobic) enhanced biological denitrification process for coking wastewater combined with MBBR and activated sludge process. Background technique [0002] Coking waste water is waste water produced during the production of coke, gas, tar and coking products in coking plants of the iron and steel industry and city gas plants. It is composed of three parts: the wet water on the surface of the furnace coal, the combined water produced by the dry distillation of the furnace coal, and the oily process wastewater in the gas pipeline and gas collection pipeline circulation oxidation pump. The water volume of this part accounts for more than 50% of the total coking wastewater ; The second is the waste water produced in the process of gas purification, such as gas final cooling water, crude benzene separation water, etc.; the third is the w...

AI Technical Summary

Problems solved by technology

However, the two-stage A / O adopts the traditional activated sludge method. Due to the high content of toxic and harmful substances in the coking wastewater and the large fluctuations in the influent water quality, it will have a greater impact on the biochemical treatment section and affect the biochemical section. When the concentration of pollutants is high, the total nitrogen in the effluent of the biochemical section cannot meet the discharge standard

In addition, the biochemical COD of the secondary A pool is very low, and supplementary carbon sources need to be added. The cost of adding carbon sources is more than 5 yuan / ton of water, which greatly increases the operating cost of the biochemical section.

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