摘要：

通过静态批次实验，探讨了硫自养反硝化、铁自养反硝化和硫铁协同脱氮系统的脱氮性能。实验结果表明，单质硫自养反硝化过程中pH由8.46降至5.46，反应前期NO₂ ^--N发生积累，最高达7.14 mg/L。TN和NO₃ ^--N随反硝化的进行呈不断降低趋势。反应5 d时TN去除率可达100%。零价铁粉的加入可以有效起到缓冲pH的作用。在硫铁协同脱氮系统中，硫铁体积比为2∶1、1∶1时，反应体系的pH可维持在6.54~7.12之间。硫铁体积比为2∶1时脱氮效果最佳，反应72 h时TN去除率可达98.5%，NO₃ ^--N去除率可达100%。在铁自养反硝化过程中，pH呈缓慢升高后逐渐稳定的趋势，由8.46增至10.02。与硫自养反硝化系统和硫铁协同脱氮系统相比，铁自养反硝化系统的脱氮性能最差，反应9 d时TN和NO₃ ^--N的去除率分别为40.52%、48.96%，且在该体系中NH₄ ⁺-N有所积累。硫铁协同脱氮系统中以硫自养反硝化为主，当硫铁体积比分别为1∶1、2∶1、1∶2时，硫自养反硝化对NO₃ ^--N去除量所占比例分别为96%、95%、88%。

关键词: 硫自养反硝化, 铁自养反硝化, 协同, 脱氮

Abstract:

The nitrogen removal performance of sulfur autotrophic denitrification， iron autotrophic denitrification and sulfur-iron synergistic denitrification systems were investigated by static batch experiments. The experimental results showed that pH decreased from 8.46 to 5.46 during sulfur autotrophic denitrification， and NO₂ ^--N accumulated up to 7.14 mg/L in the early stage of the reaction. TN and NO₃ ^--N showed a decreasing trend with denitrification. The TN removal rate was up to 100% after 5 days of reaction. The addition of zero-valent iron powder can effectively play a role in buffering pH. In the sulfur-iron synergistic denitrification system， pH of the system could be maintained between 6.54 and 7.12 when the sulfur iron volume ratio was 2∶1 and 1∶1. The best denitrification effect was achieved when the sulfur iron volume ratio was 2∶1， and the TN removal rate could reach 98.5% and NO₃ ^--N removal rate could reach 100% after 72 hours of reaction. In the process of iron autotrophic denitrification， the pH showed a trend of slow increase and then gradual stabilization， from 8.46 to 10.02. Compared with the sulfur autotrophic denitrification system and the sulfur-iron synergistic denitrification system， the iron autotrophic denitrification system had the worst denitrification performance， and the removal rates of TN and NO₃ ^--N were 40.52% and 48.96%， respectively， after 9 days of reaction. NH₄ ⁺-N was accumulated in the reaction system. The sulfur autotrophic denitrification was dominant in the sulfur-iron synergistic denitrification system， and the proportions of NO₃ ^--N removal by sulfur autotrophic denitrification were 96%， 95%， and 88% when the sulfur iron volume ratios were 1∶1， 2∶1， and 1∶2， respectively.

Key words: sulfur autotrophic denitrification, iron autotrophic denitrification, synergism, denitrification

中图分类号: 

• X703