采用好氧-缺氧SBR污水生物处理系统,考察不同进水NH4+-N浓度冲击对同步硝化反硝化型颗粒污泥脱氮过中N2O的释放规律和脱氮效果的影响.结果表明,当进水NH4+-N浓度分别从稳定的30 mg·L-1突然提高到40、60和80 mg·L-1时,氨氮去除率从80.04%降至61.40%、39.65%和31.02%,但氨氮的去除量变化不大,都在25 mg·L-1左右;另外,N2O产生量受进水NH4+-N冲击较小,在4个不同的进水NH4+-N浓度下,典型周期N2O产生量分别为3.019、3.489、3.271和3.490 mg·m-3,而且N2O释放速率都在0.004 5 mg·(m3·min)-1左右.同步硝化反硝化型颗粒污泥系统的好氧阶段和缺氧阶段均有N2O产生.不同的NH4+-N浓度冲击下,同步硝化反硝化型颗粒污泥系统对NH4+-N的去除量没有变化,但由于进水NH4+-N浓度的提高引起系统脱氮率显著下降.
The aerobic-anoxic SBR biological wastewater treatment systems were used to examine the impact of different influent NH4+-N concentrations on the release of N2O and nitrogen removal in the simultaneous nitrification and denitrification of granular sludge. The results showed that when the influent NH4+-N concentration suddenly increased from the stable concentrations of 30 mg.L-1 to 40 mg·L-1 ,60 mg·L-1 and 80 mg·L-1, the ammonia removal rate decreased from 80.04% to 61.40% ,39.65% and 31.02% , respectively, however, the ammonia nitrogen removal amount underwent little change, being about 25 mg· L-1 in all cases; in addition, there was little influence of influent NH4+-N on the N2O production, under the four different influent NH4+-N concentrations, the N2O production in a typical cycle was 3.019 mg.m-3 3.489 mg·m-3 3.271 mg·m-3 and 3.490 mg.m-3 respectively, and the N2O emission rates were all around 0. 004 5 mg· (m3 -min) -1. N2O was produced in both the aerobic stage and anoxie stage of the granular sludge simultaneous nitrification and denitrification system. Under different influent NH4+ -N concentrations, the amount of NH4+-N removal by the granular sludge simultaneous nitrification and denitrification system was not changed, but significant decrease in nitrogen removal rate was observed with the increase in the influent NH4+ -N concentration.