| With the increasing shortage of water resources and the growing requirement of environmental quality, it is imperative to raise the reuse ratio of industrial wastewater and make an effort to realize its "zero emissions".The coal chemical industry wastewater is one kind of refractory industrial wastewaters due to its complicated components, large amounts of organic pollutants with stable configuration, high concentrations of phenol and ammonia and strong biological toxicity. At present, the effluent of coal chemical industry wastewater still cannot reach emission standards after treatment, so it is more difficult to have it recycled. Aimed to realize the recycle of coal chemical industry wastewater in this dissertation, ozonation-membrane bioreactor (O3-MBR) combined process and macroporous resin adsorption process were employed for advanced treatment of the effluent of coal gasification wastewater which had been treated by the multi-stage biological processes.The effluent of coal gasification wastewater after the multi-stage biological process was further treated by O3-MBR combined process. The experimental results showed that biodegradability of wastewater was significantly improved and the color was obviously removed by O3 as the pretreatment process. Initial pH was found to have a high influence on the COD removal and alkaline conditions were more favorable. The COD removal efficiency was improved with an increase in ozone concentration. MBR was applied after O3 process for further treatment, and COD was less than 50mg/L, NH4--N concentration was 1-6mg/L and its removal efficiency was more than 70% in the effluent after MBR. The experimental results proved that adding powder activated carbon into membrane bioreactor could reinforce the treatment effect of membrane bioreactor and effectively mitigate membrane pollution.Macroporous resin adsorption process for treating coal chemical industry wastewater was also suduied in this dissertation. The effluent of coal gasification wastewater after the multi-stage biological process was directly reused for the cooling water system of the gasification plant, and macroporous resin was used to treat the concentrated solution of condensed water after circulation. Static and dynamic adsorption experimental results showed that more and more pollutants in wastewater were adsorbed by resin with an increase of resin dosage, and a linear relationship existed between the adsorption amount of pollutants and the dosage of resin. Decreasing of pH and temperature were beneficial for the adsorption of the resin. The study on adsorption dynamics showed that the H-103 macroporous resin adsorption process fitted pseudo-second-order kinetic equation. The optimal parameters for the fixed bed adsorption process were the flow rate 3BV/h. temperature 25℃and pH 6.5, under which the removal efficiencies of COD and color were 84.12% and 96%, respectively. COD of the effluent was lower than 100mg/L, and the color was almost eliminated. Resin bed adsorption capacity was 20.39mg/g, and the penetration volume was 54BV.By comparing the feasibility of practical application of the two processes, "sand filter-O3 oxidation-MBR/PAC" combined process was selected as the further treatment, and the pilot test with a scale of 0.5m3/h was carried out. When the system in a continuous and stable operation, the quality of the effluent could be found in full compliance with emission standards and reuse requirements. The corrosion experimental results showed that compared with the recirculated cooling water currently used in the factory, the natural corrosion rates of the effluent after the combined process to carbon steel and stainless steel were a bit slower. So the effluent after "sand filter-O3 oxidation-MBR/PAC" combined process could meet the requirements of circulating water.
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