Study On The Synergistic Degradation Of Ammonia Nitrogen By Sodium Acetate Under Anaerobic Electrobiology

Ammonia nitrogen is a common environmental pollutants in water treatment,this paper based on the study of electric auxiliary anaerobic ammonia oxidation in the process of the system to improve the performance of ammonia nitrogen degradation found due to the rapid degradation of nitrate nitrogen,the actual electric auxiliary microbial system(also called biological systems,hereinafter referred to as the EAMS system)has ino anaerobic ammonia oxidation environment,at the same time fast to sludge domesticated adding sodium acetate EAMS system,found that ammonia nitrogen degradation,thus found a new denitrification approach.In this paper,the synergistic degradation performance and degradation mechanism of organic compounds on ammonia nitrogen in EAMS system were studied.Firstly,the degradation effect of ammonia nitrogen in the EAMS system with and without sodium acetate was studied,and it was found that sodium acetate could synergistic degrade ammonia nitrogen in the EAMS system when the substrate was only sodium acetate,thus a new way of nitrogen removal was discovered.The optimal voltage was determined for the wastewater containing 30 mg/L(low concentration)ammonia nitrogen,and the kinetic analysis of sodium acetate synergistic degradation of low concentration ammonia nitrogen in the EAMS system was carried out.The optimal temperature was studied and the activation energy of the reaction was calculated,which was 50.098 KJ/mol.At the same time,the degradation of ammonia nitrogen at 75 mg/L(relatively high concentration)was studied,and the optimal voltage was determined.Finally,in order to study the effect of different substrates in the electrobiological system on the degradation of ammonia nitrogen,the synergistic degradation of ammonia nitrogen when the substrates are glucose and bicarbonate was studied,and the synergistic degradation of ammonia nitrogen by sodium acetate,glucose and bicarbonate under the same conditions was compared.The research results show that:(1)In electric bioreactor,through comparative study with two situations without sodium acetate and sodium acetate in EAMS system effect on the degradation of ammonia nitrogen,found in the system without sodium acetate basically remain unchanged,ammonia nitrogen content of ammonia nitrogen in sodium acetate system after gradual degradation,namely when the substrate is only sodium acetate,sodium acetate to EAMS synergy to remove ammonia nitrogen in the system.(2)In the temperature range of 291 K-301 K,the degradation rate of ammonia nitrogen increases with the increase of temperature,and the activation energy of the degradation of ammonia nitrogen by the electro-assisted anammox microbial system is estimated by Arrhenius equation to be 50.098 KJ/mol.The optimal voltage of ammonia nitrogen at low concentration(30 mg/L)was studied,and the optimal voltage of ammonia nitrogen at low concentration was determined to be 0.4 V.In order to combine practical application,the collaborative removal of relatively high concentration(75 mg/L)ammonia nitrogen by sodium acetate in EAMS system was discussed,and the optimal voltage of 75 mg/L ammonia nitrogen was determined to be 0.6 V.By comparing the degradation of ammonia nitrogen with different concentrations at the voltages of 0.4 V and 0.6 V respectively,it is found that the degradation of high concentration ammonia nitrogen requires a higher voltage,while the degradation of low concentration ammonia nitrogen requires a lower voltage.In addition,when the initial concentration of ammonia nitrogen is 75 mg/L,ammonia nitrogen is degraded at a voltage of 0.6 V.When it is degraded to a low concentration,adjusting the voltage to its appropriate voltage,namely 0.4 V,can improve the degradation efficiency of ammonia nitrogen.(3)Simulated wastewater formula of substrate change into glucose for energy and bicarbonate,observe them respectively in the electrical coordination of ammonia nitrogen removal in biological system,found that when the substrate is sodium acetate best co-treating effect of ammonia nitrogen,bicarbonate second,glucose,and discusses the causes of this phenomenon:In this EAMS system,ammonia nitrogen degradation occurs at the positive electrode.When glucose is used as substrate,although the carbon source is provided,it needs to be converted and reused by denitrifying bacteria first.This process is relatively complex,and the reduction reaction of glucose in the electronegative electrode requires a large amount of energy,resulting in poor synergistic degradation effect of ammonia nitrogen.When ammonium bicarbonate is used as the substrate,although the bicarbonate can be reduced in the electronegative electrode to make the whole system complete cycle,the whole reactor cannot provide nutrients for microorganisms because there is no organic matter in the reactor,so the ammonia nitrogen will not be degraded to a certain extent.When sodium acetate as the substrate,acetic acid root can carry on the reduction reaction in the negative electrode makes the REDOX reaction of the whole system gather together into a full circle,and the reduction of acetic acid as the organic matter can provide electricity the microbes in biological systems with enough carbon sources,so compared with two other substrates for the degradation of ammonia nitrogen is thorough,degradation of performance is the highest and the effect is the best.