两级自养反硝化实现垃圾渗滤液的深度脱氮

针对目前生物工艺难以解决垃圾渗滤液深度脱氮的问题,探究了短程硝化反硝化-厌氧氨氧化-硫自养反硝化(两级自养)工艺处理高氨氮、低C/N比垃圾渗滤液的脱氮效果。结果表明, 当进水垃圾渗滤液中氨氮平均浓度为2 560 mg·L⁻¹,COD值为4 000~5 000 mg·L⁻¹时,经过短程硝化反硝化-厌氧氨氧化处理后,总氮去除负荷可达1.19 kg·(m³·d)⁻¹、总氮去除率可达93.1%(出水TN=176.3 mg·L⁻¹)、COD去除率可达52.2%。但是,厌氧氨氧化反应器出水中${rm{NO}}_x^{-} $-N浓度为154.5 mg·L⁻¹,仍未达到我国生活垃圾填埋场垃圾渗滤液处理排放标准(TN≤40 mg·L⁻¹)。在厌氧氨氧化反应器之后串联硫自养反硝化,整体工艺最终出水${rm{NH}}_4^{+} $-N、${rm{NO}}_2^{-} $-N、${rm{NO}}_3^{-} $-N平均浓度分别为1.9、0.6、9.7 mg·L⁻¹,TN≤15 mg·L⁻¹,进水总氮去除率为99.5%。在短程硝化反硝化-厌氧氨氧化-硫自养反硝化两级自养深度脱氮反应系统中实现了垃圾渗滤液深度脱氮。

Deep denitrification of landfill leachate by two-stage autotrophic denitrification process

In view of the difficulty of deep denitrification in the treatment of landfill leachate by biological process at present, a new process coupling partial nitrification-denitrification-anaerobic ammonia oxidation (ANAMMOX) and sulfur-driven autotrophic denitrification (SAD) was applied to treat the landfill leachate with high ammonia nitrogen and low C/N ratio. The results showed that at the ammonia concentrations of 2 560 mg·L−1 and COD of 4 000~5 000 mg·L−1 in the influent landfill leachate, the total nitrogen removal load, nitrogen removal efficiency and COD removal efficiency were 1.19 kg·(m3·d)−1, 93.1% (the total nitrogen concentration in effluent was 176.3 mg·L−1), and 52.2% after partial nitrification-denitrification-ANAMMOX treatment, respectively. However, ${rm{NO}}_x^{-} $-N concentration in the effluent of the ANAMMOX reactor was 154.5 mg·L−1, which could not meet the effluent quality standard of TN≤40 mg·L−1 in domestic solid waste landfill. When the SAD was coupled with partial nitrification-denitrification-ANAMMOX process in a series connection mode, the average concentrations of ${rm{NH}}_4^{+} $-N, ${rm{NO}}_2^{-} $-N, ${rm{NO}}_3^{-} $-N in the effluent of the whole process were 1.9, 0.6 and 9.7 mg·L−1, respectively, the total nitrogen concentration was below 15 mg·L−1, the nitrogen removal efficiency reached 99.5%. Deep denitrification of landfill leachate was achieved by two-stage autotrophic deep denitrification process of partial nitrification-denitrification-ANAMMOX-SAD.