Research On Advanced Treatment Technology For Industrial Wastewater Of Gansu Huineng Biological Engineering Co.,Ltd.

Gansu Esigma Biological Co.,Ltd.is a high-tech enterprise specializing in biological fermentation.The main production line includes seed culture,fermentation,pretreatment of fermentation broth,plate and frame filter pressing,flash drying,etc.Its products are mainly1300t/a nasitide premix and refined powder.While changing the production raw materials,the production line can also produce Maduramycin,Enramycin,Aureomycin,Oxytetracycline and other products.The company has set up a sewage treatment station.The treatment process is anaerobic-anoxic-aerobic activated sludge process coupled with BAF process.The treated wastewater is discharged into the sewage plant in the industrial park.The wastewater treated by the company's self-built sewage treatment station can meet the influent requirements of the sewage plant in Wuwei Industrial Park and the relevant specifications for production wastewater in fermentation industries.The two standards specify the treatment requirements of each index:CODcr?600 mg/l,BOD5?400 mg/l,SS?250 mg/l,NH3-N?35 mg/l.However,there is no clear stipulation on chromaticity in the two standards,which makes it more difficult to treat chromaticity in downstream sewage plants and cannot meet the environmental protection requirements of Wuwei City.The research of this topic is to adopt membrane bioreactor as the advanced treatment process of the company in the follow-up of the existing sewage treatment station of the company,determine the best treatment process parameters after studying the characteristics of nositide production wastewater,and analyze the treatment effect of MBR reactor on nositide wastewater.Each index concentration of effluent after treatment from the original sewage treatment station of the Company is:COD_Crr 260?340mg/L,BOD₅ 120?150mg/L,NH₃-N 10?20mg/L,SS 30?60mg/L,and the effluent enters MBR reactor for advanced treatment.The experiment passed but the method of single factor control was adopted.When the concentration of activated sludge was controlled to 5500mg/L and the concentration of DO was controlled to2mg/L,the optimal HRT time was determined to be 4h.Then the concentration of activated sludge is determined to be 5500mg/L,and the optimal concentration range of DO is determined to be 1.5 mg/L?2.5 mg/L when HRT is 4h.The optimum operating parameters are:sludge concentration 5500mg/L,DO concentration 1.5 mg/L?2.5 mg/L,HRT 4h,intermittent high-intensity aeration mode,peristaltic pump stop time ratio 10min/5min.Under the best operating conditions,the experimental device was started to monitor the pollutant indexes of the effluent quality after advanced treatment,and the treatment effect of wastewater chromaticity was studied.Combined with the local temperature change in Wuwei City,the problem of microbial activity reduction at low temperature was solved by temperature control device and measures to increase sludge concentration.In the operation stage of the reactor,when the water output decreases by 20%?30%of the normal water output,the membrane is cleaned.In the experiment,aeration cleaning and off-line chemical cleaning methods are combined to measure the recovery of membrane flux.After cleaning,the membrane flux can be recovered to 95%of the new membrane flux.After the small-scale experiment,the size of MBR membrane pool and the number of membrane modules to be established by the future company are designed and calculated,and the size of MBR membrane pool is 105m³ and the number of membrane modules is 5 groups.In the actual project,the parameters for cleaning the membrane tank are:0.1%NaClO concentration of cleaning agent,2h cleaning period,20min soaking time and 0.5min backwashing time.Experiments show that membrane bioreactor can be used as an advanced treatment process for nositide production wastewater.It is found that the MBR reactor has good impact load resistance,and the problem of periodicity of nositide wastewater can be solved.At low temperature,the reactor is heated and the concentration of activated sludge is increased to ensure the efficient denitrification capacity of the reactor.Finally,the effluent treated by the reactor meets the first-class A standard of pollutant discharge standard?GB18918-2002?for urban sewage treatment plants,and the color of the effluent quality is 24 degrees.