COD浓度对反硝化除磷及N2O释放影响

Effect of COD concentration on phosphorus removal by denitrification and nitrous oxide emission

接种普通活性污泥,在厌氧/缺氧SBR系统驯化51 d,反硝化脱氮除磷效率分别达到(96±2)%和(88±5)%。在此基础上,取厌氧末活性污泥,研究了COD浓度(0,26.25,87.5 mg/L)对亚硝酸型反硝化除磷性能及N_(2)O释放的影响。结果表明,随着COD浓度的增大,脱氮效率由55.44%升至63.50%和96.44%;同时,COD被合成PHB,并发生释磷的现象,导致除磷效率由33.54%降至26.87%和-0.016%;N_(2)O转化率(N_(2)O-N释放量/去除的TN量)由25.08%减少为22.96%和11.85%。高浓度COD有利于提升反硝化效率,并降低N_(2)O的释放,但会降低除磷效率。

Inoculated with normal activated sludge,denitrification and phosphorus removal were successfully achieved in anaerobic/anoxic SBR system after 51 d of domestication,and the denitrification and phosphorus removal efficiency reached(96±2)%and(88±5)%,respectively.On this basis,anaerobic end activated sludge was taken and the effects of COD concentrations(0,26.25,87.5 mg/L)on the performance of nitrite type denitrification and phosphorus removal and N_(2)Orelease were investigated using batch tests.The nitrogen removal efficiency increased from 55.44%to 63.50%and 96.44%with increasing COD concentration;meanwhile,COD was synthesized into PHB and phosphorus release occurred,resulting in a decrease of phosphorus removal efficiency from 33.54%to _(2)6.87%and-0.016%;N_(2)Oconversion(N_(2)O-N release/TN removed)decreased from 25.08%to _(2)2.96%and 11.85%.High COD concentration is beneficial to enhance denitrification efficiency and reduce N_(2)Orelease,but it will reduce phosphorus removal efficiency.