Study On The Process Performance Of The Wastewater Denitrifying Phosphorus Removal Electrogenesis

The system of denitrification phosphorus removal electrogenesis is a new water treatm ent process which can generate the power at the same time,simulated water as the resear ch object.Feasibility analysis of coupling process,starting of the device and influence fact ors of the system of denitrification phosphorus removal electrogenesis are studied in thispaper which achieve coupled of continuous flow two sludge denitrifying phosphorus remo val process and MFC.It can produce electricity at the same time as the sewage treatment and has its advantage that realizes energy conservation,emission reduction and environ mental protection in its own system.We analyzed production of microorganisms,device structure and reaction substrates in this paper,which provided the theoretical basis of the successful coupling of the process of denitrification phosphorus removal with MFC.On the basis of the summary of the operating principle and the mechanism of electricity production of system of the denitrification phosphorus removal.The influence factors and operating parameters of the system are discussed from the electrode material,electrode position,membrane structure,carbon source,redox potential,hydraulic retention time,MLSS,temperature,carbon source,pH value and so on.And then give the prospects for potential applications of the system of denitrification phosphorus removal electrogenesis.Sludge in the system of denitrification phosphorus removal electrogenesis is gotten Simultaneous domestication and cultivation with the way of continuous flow two sludge.during the operation of the device,the dissolved oxygen concentration in the anaerobic tank is controlled by 0.2mg/L,the nitrification tank is 1.0-2.0mg/L,the anoxic tank is about 0.5mg/L,and the reactor is operated at room temperature,and the water temperature of the oxygen tank,the cathode chamber and the anoxic tank is controlled at 25℃.After the device was successfully launched,the removal rate of COD was between 65%-75%,and the removal rate of ammonia nitrogen was between 60%-70%,the removal rate of phosphorus was about 60%,and the highest removal rate of COD,ammonia nitrogen and phosphorus was 74.03%,70.46%and 63.02%respectively.Efficiency of electricity production is stable and efficient,generates a voltage value generally around respectively,the strength of the current is about 6.31mA,the highest voltage and current intensity has reached the 0.65v and 7.69mA,maximum output power 44mW/m2 and resistance about to 900 ohms.The oxidation reduction potential,hydraulic retention time and external resistance are the most important factors in the process of denitrification phosphorus removal electrogenesis.When the ORP value of the anaerobic pool is set at-400mv,it is conducive to the full release of phosphorus,the instantaneous output voltage value is higher,the power production effect is good,and the ORP value of the anoxic tank is in favor of simultaneous removal of nitrogen and phosphorus.By adjusting the number of revolutions of the peristaltic pump to change the reaction device of hydraulic retention time,when the external resistors set in 900 ohms,the HRT of the anaerobic tank were set at 1.5h,2.5h,3.5H.At this time corresponding to the anoxic tank hydraulic residence time averaged 2.3 h,3.8 h and 6 h,respectively.When HRT is set up in 2.5h,the phosphorus release rate of denitrification and phosphorus,and the phosphorus release effect are the best.When HRT is 1.5h,the organic content is more abundant,the output power is the best,the average voltage of the output is the largest.When HRT was set up in 2.3h to 3.8h,the removal efficiency of nitrogen and phosphorus was satisfactory,and the removal efficiency was small,and the removal efficiency was relatively stable.The load resistance of the device is set at 100,500,900 and 1200,respectively.And then,give the analysis of the production and wastewater treatment of the system.When the external resistance is closest to the internal resistance of electricity generation device of 900 ohms and denitrifying phosphorus removal with generation of electric energy.At this time the MFC maximum output power density.When the external resistor for 900 ohms,the sewage in the COD removal rate is the highest,as well as electricity production performance is the best,when the external resistor for 500 ohms,system of nitrogen and phosphorus removal rate of the highest external resistor for 900 ohms,organic carbon content decreased,nitrogen and phosphorus removal effect is poor.To sum up,After the process of denitrification phosphorus removal and MFC are coupling successfully.TN,TP and COD in the wastewater are reduced,at the same time,the renewable green energy is generated and the output voltage is stable.