颗粒活性炭对膜生物反应器脱氮性能的影响

为了考察投加颗粒活性炭(GAC)对膜生物反应器(MBR)运行过程和处理效果的影响,研究了MBR和GAC-MBR透膜压差、膜通量的变化情况和脱氮性能,并采用ASM1模型对2个反应器进行数学模拟.结果表明,MBR和GAC-MBR的运行周期分别为75,150h,说明GAC的加入能够显著减缓MBR膜污染的速度,延长MBR的运行周期.MBR和GAC-MBR氨氮浓度分别为0.5,6mg/L;硝氮浓度分别为4.5,2mg/L;总氮浓度分别为5,10mg/L,出水COD均低于20mg/L,出水能符合《城镇污水处理厂污染物排放标准(GB 18918-2002)》中的一级A标准.采用ASM1进行工艺数学模拟,模拟出水与实际测量值基本吻合,2个反应器中主要微生物为异养菌和氨氧化菌,异养菌在MBR和GAC-MBR中的质量分数分别为95.5%和97.7%;好氧氨氧化菌分别为4.4%和2.3%,说明投加颗粒活性炭能有效的缓解膜污染,并对污染物具有良好的处理效果.

Effect of dosing GAC on the denitrification performance of membrane bioreactor

In order to study the effect of addition GAC on operation parameters and treatment efficiencies in the MBR,the denitrification performance,the permeable membrane pressure and the membrane flux of membrane bioreactor(MBR) and granules activated carbon-membrane bioreactor(GAC-MBR) were investigated.The two bioreactors were simulated by the activated sludge model No.1(ASM1).The operation period of MBR and GAC-MBR were 75,150h,respectively.The fouling rate of MBR was slowed,the opearation period was prolonged by addition GAC.The effluent ammonia nitrogen concentration of MBR and GAC-MBR was 0.5,6mg/L,respectively.The effluent COD concentrations of them were less than 20mg/L.The effluent nitrate concentration of MBR and GAC-MBR was 4.5,2mg/L.The effluent total nitrogen concentrations of MBR and GAC-MBR was 5,10mg/L.The outflow water quality was better than the first grade A required by the discharge standard of pollutants for municipal wastewater treatment plant.Using the activated sludge model No.1(ASM1) to simulate two bioreactors,the simulated value of water quality was similar to the experimental value;the most of microorganisms were ammonia oxidizing bacterias and heterotrophices.The mass faction of heterotrophices was 95.5%,97.7% in the MBR,GAC-MBR,respectively.The mass faction of ammonia oxidizing bacterias was 4.4% in the MBR and 2.3% in the GAC-MBR,respectively.Addition GAC could relieve the membrane fouling and have a good removal efficiency of the pollutants.