S^(2-)/NO_3^--N对硫自养反硝化与厌氧氨氧化耦合脱氮除硫启动的影响

Effects of S^(2-)/NO_3^--N on Sulfur Autotrophic Denitrification and Anaerobic Ammonia Oxidation Combined Process for Nitrogen and Sulfur Removal

为寻求经济、有效的同步脱氮除硫工艺,采用HABR(复合式厌氧折流板反应器),接种厌氧氨氧化活性污泥,以人工模拟废水为研究对象,在进水p H为8.0、温度为(32±1)℃、HRT为6.5 h的条件下,调整进水S2-/NO3--N〔n(S2-)∶n(NO3--N)〕分别为2.0∶5、3.5∶5、5.0∶5、6.5∶5,研究其对硫自养反硝化和厌氧氨氧化耦合工艺启动的影响,试验连续进行了54 d.结果表明:当S2-/NO3--N<1时,S2-的供应量相对不足,导致硫自养反硝化生成的NO2--N量不足,进而影响后续厌氧氨氧化效果,NH4+-N去除率较低,平均值为53.5%,同时剩余NO3--N继续氧化硫自养反硝化生成的S0,致使出水中ρ(SO42-)增大;当S2-/NO3--N=1时,S2-供应量充足,硫自养反硝化生成NO2--N量最大,厌氧氨氧化效果最好,NH4+-N去除率最高,平均值为65.1%;当S2-/NO3--N>1时,S2-过量,S2-去除率下降.试验通过控制S2-/NO3--N,在HABR内成功实现了硫自养反硝化和厌氧氨氧化耦合工艺启动,NH4+-N、S2-、NO3--N最大去除率分别为74.3%、99.0%、99.5%,S2-/NO3--N=1为最佳比例.

The startup of sulfur autotrophic denitrification（ SAD） and anaerobic ammonia oxidation（ anammox） combined process and the effect of S2-/NO3--N on the system performance was investigated using a Hybrid Anaerobic Baffled Reactor（ HABR）. Anammox sludge was filled as the seeding sludge,and artificial simulated wastewater was used as the influent. The reactor was continuously operated for 54 days under the conditions p H 8. 0,temperature（ 32 ± 1） ℃ and HRT 6. 5 h. The results showed that S2-was inadequate for NO3--N reduction,and insufficient NO2--N product led to lower NH4＋-N removal rate by anammox when S2-/NO3--N 1. The residual NO3--N continuously oxidized from elemental sulfur to sulphate,which caused higher sulphate concentration in the effluent. When S2-/NO3--N =1,S2-was adequate for NO3--N reduction,and the maximum NO2--N was generated. The NH4＋-N average removal rate was 65. 1%,which was the highest by anammox. When S2-/NO3--N 1,the S2-removal rate declined for excessive concentrations. SAD and anammox were successfully coupled in HABR. The maximum removal rates of NH4＋-N,S2-,NO3--N were 74. 3%,99. 0% and99. 5%,respectively. The optimum ratio of S2-/NO3--N was 1 for SAD and anammox combined process.