Parameter Research And Engineering Design Of ABR Treating Dye Intermediate Wastewater

Dye intermediate wastewater has the characteristics of high salinity,high content of organic pollutants,refractory degradation,poor biodegradability and high chroma,and the treatment of it has always been a difficult and painful point in the environmental protection field.In this paper,the effluent from the hydrolyzed acidification tank of the wastewater treatment station of a dye intermediate production plant in Hebei Province was studied.The ABR reactor was constructed by the addition of the filler,and the activated sludge was inoculated into it.The reactor was started by the step-by-step growth load method.After the start-up,the influences of influent COD concentration,filler addition and hydraulic retention time on the treatment effect of ABR were studied.The treatment effect of ABR was monitored by pH,chroma,COD removal rate,B/C,NH4+-N,TN,sludge activity and other indicators.And,the abundance and diversity of microorganisms in sludge were studied,and the functional bacteria and dominant bacteria were analyzed.Finally,the engineering design of ABR was carried out based on the parameters of the small test.The start-up phase of ABR was divided into sludge adaptation stage and step-by-step increase load start-up stage,which totally lasted 73 days.In the sludge adaptation stage,COD of influent was controlled at 500.0 mg/L,and COD removal rate was nearly 53%after 33 days of adaptation.After that,the ABR was started by step-by-step increasing load method until the plan sewage concentration is reached,and the COD removal rate in the reactor reaches 70%.After the start of the experiment,the HRT was optimization and the HRT was controlled at 144 h,120 h,96 h,72 h,48 h and 24 h,respectively.When HRT was 48 h,the COD removal effect was the best,the removal rate was 65%.Then,the characteristics of ABR were studied under the optimal HRT conditions.The removal efficiency of the whole process was analysed through the continuous monitoring of COD,NH4+-N and TN.Under the condition of HRT at 48 h,the pH of ABR effluent was stable at 7.5-7.7,and the COD removal rate was finally stable at 70%.MLVSS/MLSS was maintained at around 0.5.Since the organic N in the influent was converted to NH4+-N by the action of microorganisms,the effluent NH4+-N was 39.0 mg/L and the effluent TN was 35.0 mg/L.High-throughput sequencing indicated that the total number of species increased slowly in each compartment of the ABR,and each index indicated that the richness of the microbial community in the react gradually increased.The species richness of the methanogenic stage of the ABR three and four compartments is the largest,which is larger than rhat of the first and second compartments.The dominant bacteria in the reactor were Thermotogae and Proteobacteria,and the microorganisms with denitrification function were Proteobacteria and Fusarium,and the Thermovirga,which can strengthen the degradation of industrial toxic wastewater.Studying the microbial community structure in biological processing and correlating it with the environment of the treatment process helps to explore the role of different microbial populations in the treatment processFrom the test results,the addition of filler to the ABR can speed up the start-up speed of the reactor,and the sludge attached to the filler can increase the amount of sludge and enhance the pollutants removal effect of the reactor on the pollutants.Finally,the removal rate of COD in the target wastewater by ABR is stable at 70%,which can strengthen the effluent of the hydrolysis acidification tank and reduce the final effluent pollution index of the plant wastewater station.The test process composite ABR is suitable for treating the effluent after hydrolyzed acidification tank oxidation of the sewage treatment station of a dye intermediate production plant.