A2N/BAF组合工艺深度除磷脱氮研究

针对我国南方低碳氮比生活污水,开展以BAF为硝化单元的A2N工艺小试研究,针对超越污泥携带NH4+导致出水超标及二沉池出水SS偏高时TP超标问题,进一步研究增加二级BAF单元的处理效果,形成A2N/BAF工艺.结果表明:A2N段对COD、NH4+-N、TP平均去除率分别为82.0%、70.9%、90.0%;当进水NH4+-N超过40.0 mg/L时,二沉池出水NH4+-N超过10.0 mg/L;二级BAF单元能够硝化二沉池出水NH4+-N及截留SS,最终出水COD、TP、NH4+-N、NO3--N、SS平均质量浓度分别为35、0.35、1.06、8.01、7 mg/L,稳定达到一级A标准.

Study on combined A2N/BAF process for advanced nitrogen and phosphate removal

The A2N process with BAF as a nitrification unit was researched aiming at the low carbon and nitrogen ratio domestic wastewater in southern China.According to the problems that effluent ammonia exceeded the standard because of the ammonia carried in surpass sludge and total phosphate couldn’t reach the discharge standard when SS of secondary settling tank was high,a secondary BAF was set up,and the total treatment effect of A2N/BAF process was studied.Results showed that the average removal rates of COD,ammonia and TP of A2N stage were 82.0%,70.9% and 90.0%,respectively.Effluent ammonia concentration of secondary settling tank exceeded 10 mg/L when influent was more than 40 mg/L.Average concentration of COD,TP,ammonia,nitrate and SS in final effluent were 35,0.35,1.06,8.01 and 7 mg/L,respectively,which had satisfied the A-level of the national standards.