Study On The Mechanism Of Micro-electric Field Provided By MFC To Suppress MBR Membrane Fouling

Membrane bioreactor(MBR)is an efficient water treatment technology,which has high-quality recycled water and energy.However,membrane fouling is the main disadvantage of the MBR process,the main reason is that it will cause a decrease in permeability.Membrane flux or transmembrane pressure(TMP)increases with the increase of processing time,which results in an increase in membrane operating costs and ultimately shortens the life of the membrane.Therefore,membrane fouling is still a major issue limiting the development of MBR.When the microbial fuel cell treats sewage,it can convert chemical energy in organic matter into electrical energy and produce clean energy.In this experiment,MFC and MBR are combined to form an MFC-CMBR integrated system.The electric field generated by MFC is appended to the outside of the MBR to form a ring-shaped micro electric field.Using the MFC-EMBR as a control,the integrated system can reduce membrane pollution To improve the effect of sewage treatment,the research results show that:(1)Under the operating conditions of domestication for five cycles,external resistance of1000?,and p Henol as substrate,the maximum voltage of the MFC-CMBR integrated system is about 0.78V,the maximum current density is 462.15m A/m~2,and the maximum power density is 160.36m W/m~2,internal resistance is 100?.The COD degradation rate is about96%.(2)The additional electric field can effectively slow down membrane pollution.The TMP growth of the MFC-EMBR integrated system with an additional electric field is slower than that without an electric field,and the period is extended from 18 days to 24 days,and it can also be seen by scanning electron microscopy.Irreversible membrane contamination.From the analysis of the average growth rate of membrane pore resistance,the MFC-EMBR integrated system has a significant inhibitory effect on the growth rate of membrane pore pollution.(3)Through Fourier infrared spectroscopy(FTIR),it can be concluded that the main pollutants are polysaccharides and proteins,which are the main components of soluble microbial metabolites(SMP)and extracellular polymers(EPS).Under the action of the electric field,through the analysis of the characteristics of the mud cake layer,it is concluded that the content of polysaccharides and proteins will be suppressed,reducing their adhesion on the membrane surface;through the analysis of SMP and EPS around the MBR membrane module,it is found that an external electric field Under the action,SMP and loose extracellular polymer(LB-EPS)will be far away from the membrane module,and its concentration will increase with the increase of the distance from the membrane module;while TB-EPS is not affected by the electric field and is uniform Ly distributed.The results of this study show that SMP and LB-EPS can move away from the surface of the MBR membrane under the action of a micro electric field,which can effectively inhibit MBR membrane pollution.