Study on Domestic Sewage Treatment by Biological Aerated Filter

[Objective] To study the treatment effect of domestic sewage in small towns by Biological Aerated Filter(BAF).[Method] The domestic sewage was sampled from small towns,and then treated by BAF,the contents of NH3-N,TN,TP and COD were monitored.[Result] The BAF had good effect for treating domestic sewage,especially COD,The contents of NH3-N,TN,TP and COD in influent were 9.7-68.9 mg/L,18.1-73.2 mg/L,1.79-8.78 mg/L and 170-336 mg/L,respectively,their average removal efficiency was 85.9%,61.4%,76.7% and 89.2%,respectively,and the effluent COD met the first class A criteria(GB 18918-2002),the effluent NH3-N,TN and TP met the first class B criteria.Meanwhile,the study revealed that the daily treatment amount showed a positive effect on effluent especially on TN and TP,but too high influent concentration was not good for the improvement of effluent quality.[Conclusion] The biological aerated filter can be used for the treatment of domestic sewage in small towns with high economic benefits,and the treated sewage can be up to or above the discharge standards.