基于侧流FNA处理的颗粒-絮体污泥CANON启动

为探究游离亚硝酸(FNA)侧流处理絮体污泥抑制亚硝酸盐氧化菌(NOB)活性启动全程自养脱氮(CANON)工艺的可行性,考察了FNA处理对氨氧化菌(AOB)和NOB活性的影响,探究在颗粒-絮体污泥SBR反应器中水力筛分的絮状污泥经侧流FNA处理的运行效果. 结果表明:0.6mg/L FNA处理后的R1经过30d运行,NH₄⁺-N去除率恢复到处理前的水平,并且短程硝化稳定,系统平均出水总氮为13.84mg/L,且△NO₃^--N/△NH₄⁺-N比值接近CANON反应方程式理论比值0.11,成功启动CANON工艺. 而0mg/L FNA处理的R2由于NOB大量增殖导致启动失败. 批次试验结果证实,经过0.6mg/L FNA处理后,6h内NOB活性仅为对照组(FNA=0mg/L)的16.39%,并且在随后的运行中并未发现NOB活性的恢复,NOB得到了有效的抑制. 但与此同时,AOB的活性也受到了影响,反应器中NH₄⁺-N去除率仅为处理前的69.69%,AOB活性6h仅恢复68.06%.

Start - up of granular - flocculate sludge CANON process based on side - flow FNA treatment

In order to evaluate the feasibility of the free nitrite (FNA) lateral flow treatment of flocculent sludge by initializing the autotrophic nitrogen removal (CANON) processing, this study was conducted to investigate effects of the FNA treatment on ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) activities and the operation efficiency of hydraulically screened flocculent sludge treatment in the granular-flocculation sludge SBR reactor. The results show that after 0.6mg/L FNA treatment of R1 for 30days, the removal rate of NH₄⁺-N returned to the level before the treatment and the short-range nitrification was stable. The average total effluent nitrogen of the system was 13.84mg/L; and the △NO₃^--N/△NH₄⁺-N ratio was close to the theoretical one of the CANON reaction equation of 0.11, indicating successful start of the CANON process. However, R2, treated with 0mg/LFNA failed to start due to the massive proliferation of NOB. The batch test results confirm that after the treatment of 0.6mg/L FNA, the NOB activity was only 16.39% of the control group (FNA=0mg/L), and the recovery of NOB activity was not found in subsequent operation thus NOB was effectively inhibited. Additionally, the activity of AOB was affected because the removal rate of NH₄⁺-N in the reactor was only 69.69% of that of before treatment and the activity of AOB recovered by only 68.06% after 6h.