Advanced treatment process for coking wastewater

Abstract

The invention relates to an advanced treatment process for coking wastewater. The advanced treatment process comprises the following steps of (1) filtration, (2) magnetic separation and purification,(3) sedimentation treatment through addition of a low-temperature coagulant aid, (4) electrocatalytic oxidation, (5) biological treatment and (6) filtration through a membrane filter. The advanced treatment process for the coking wastewater has the advantages that the low-temperature coagulant aid is adopted to improve the coagulation effect of the lower-temperature coking wastewater, thereby being conductive to the subsequent purification efficiency of the coking wastewater; then electrocatalytic oxidation is carried out, hydroxyl radicals with very high oxidation potentials are generated, organic matter in the wastewater is oxidized on a large area, and the aeration plays a stirring role and can also promote the discharge of dross in the process of electro-catalysis; the coking wastewater of which COD and ammonia nitrogen in effluent both meet the standards can be prepared by using the above process to treat the coking wastewater.

Description

technical field [0001] The invention relates to the technical field of wastewater treatment, in particular to a coking wastewater advanced treatment process. Background technique [0002] Coking wastewater is a recognized industrial wastewater that is difficult to biodegrade. The difficulty lies in the poor biodegradability of the wastewater. In addition to inorganic pollutants such as ammonia, cyanide, and thiocyanate, it also contains impurities such as phenols, naphthalene, pyridine, and quinoline. Cyclic and polycyclic aromatic compounds (PAHS) are difficult to biodegrade. These substances can have a long-term impact on the environment, and some of them have been confirmed as carcinogens by research. In addition, high concentrations of ammonia nitrogen have a strong inhibitory effect on microbial activity. Biodegradation Nitrogen does not work well. At present, the treatment of coking wastewater generally adopts biological treatment methods based on A / O or A / O / O, A / A / O,...

AI Technical Summary

Problems solved by technology

Due to the utilization of different degradation characteristics of anaerobic, facultative and aerobic bacteria, these processes have greatly improved the removal of COD and ammonia nitrogen compared with ordinary activated sludge methods, but because coking wastewater contains many types of refractory toxic organic substances The complex and changeable water quality and quantity make the anoxic-aerobic activated sludge process vulnerable to impact, especially the autotrophic nitrifying bacteria in the aerobic stage, due to the long generation time, the recovery is slow after being impacted, and the nitrification efficiency decreases, which makes the process It is difficult for the effluent COD and ammonia nitrogen of the process to reach the standard at the same time