MABR Study Of Operation Efficiency And Kinetic Model Of Pollutant Degradation With Simulated Domestic Wastewater

The new membrane aerated biofilm reactor(MABR) has great application prospect in the sewage treatment because of its high oxygen utilization, decarburization and denitrogenation at the same time.Based on the simulated sewage, firstly, this paper tracked the influence of aeration pressure, circulating velocity and influent COD concentration on decarburization and denitrogenation in MABR system. Secondly, the influence of hydraulic retention time(HRT), aeration pressure and C/N ratio on MABR long continuously operation efficiency were examined and the process parameters was optimized. Finally, combined with engineering common emergency, a series of shock and recovery experiments were designed consisting of high organic load, high ammonia nitrogen load, strong alkali and strong acid. The experimental results show that the MABR system has the characteristic of fast startup and COD degradation efficiency is together controlled by hydrotechnics conditions, differential concentration and activity of biofilm. In MABR system, biological denitrification process is affected by the change of the circulation flow rate and aeration pressure significantly. The process of nitrification and denitrification could be completed at the same time at high circulation velocity and appropriate aeration pressure. When the HRT is 8 h, aeration pressure is 0.15 MPa, C/N ratio is 4, effluent water quality is best. COD, NH4+-N, TN removal rates are higher than 95%. In addition, the system has a certain impact resistance and the ability to repair itself, TN removal efficiency changes significantly and sensitively compared to COD when faced to impact.In addition, this article firstly combined the kinetic model of substrate degradation with material balance equations of the pollutants in MABR system. It shows that the maximum degradation rate and saturation rate constant of COD are 1.16 d-1 and 29.9 mg/L. The maximum degradation rate and saturation rate constant of NH4+-N are 0.051 d-1 and 0.358 mg/L respectively. According to verification and error analysis, the results show that the degradation kinetic models are appropriate for MABR and the error range is 4-10%. The above experimental results will help people to deepen cognition about pollution degradation and removal process in MABR system, also provide a certain practical and theoretical support for the application and development of the new sewage treatment technology.