Experimental Study On Domestic Wastewater Treatment By Membrane Bioreactor Combined With Electrocoagulation

In today's society,the situation of water resource shortage in the whole world is very serious.China has a large amount of water,but there are still some problems such as uneven distribution,less water per capita and serious pollution.Therefore,it is one of the most important measures to solve the problem of water shortage and achieve the sustainable development of society.Membrane Bio-Reactor(MBR)is a highly efficient wastewater treatment technology,which combines the Membrane filtration technology and organic combination of sewage biological treatment technology,whose advantages are low cost,simple operation,good treatment effect,accounting for small area,easy to maintain,high removal rate of organic pollutants and so on.But the serious problem of Membrane fouling,the ability of denitrification and dephosphorization capability is not ideal.As a result,to mitigate the Membrane fouling of MBR process,strengthen its denitrification and phosphorus removal effect is always the key point of the research in this field.Electro-coagulation(EC)is a kind of wastewater treatment technology that flocculates contaminants in water without applying chemical coagulants through the addition of an electrode plate and applying current to it.It combines three kinds of technology,including electro-chemical,chemical coagulation and air-flotation with many types of pollutants removal,efficiency removal,less secondary pollution.In the same time,process and equipment is simple.It not only has good maneuverability,and many other advantages,but also in terms of deepening the sewage denitrification and phosphorus removal has a good effect.In recent years,it is widely used in the treatment of oily wastewater,heavy metal wastewater,dye wastewater and so on.However,it is not widely used in the treatment of domestic sewage due to the problems of power consumption and heavy metal consumption.Therefore,this research will be electric flocculation technology and the organic combination of MBR process.The domestic wastewater was treated by the electro-flocculation/membrane bioreactor(EC-MBR)to investigate its effect on membrane fouling and to enhance the effect of nitrogen and phosphorus removalusing electric flocculation/membrane bioreactor(EC-MBR)treatment of sewage,explore its influence on membrane fouling and strengthen the effect of nitrogen and phosphorus.The results show that when the reactor temperature is 19?23 ?,the pH value is 6.5?7.5,the HRT is 8h,the initial MLSS is 4000mg/L,the current density is 0.1481 mA/cm2,The average removal rate of COD,ammonia nitrogen and total phosphorus were 87.95%and 85.55%respectively with EC-MBR process being the best.The average removal rate of COD,And 83.10%respectively.After the stable operation,the effluent quality meets Grade A standard in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB18918-2002),which is 15.74%,16.07%and 22.32%higher than that of ordinary MBR process respectively.In addition,the electroflocculation part of the membrane pollution have a certain degree of inhibition.The above results show that EC-MBR process has the advantages of good effluent quality,stable effect,high mechanical strength and good retention capacity of the ceramic flat membrane,which can be recycled repeatedly.The experimental system has good application prospect.This article provides a certain theoretical basis for the in-depth study and practical application of the technology,which is of guiding significance and reference value.