摘要：

构建了硫/菱铁矿组合系统进行自养反硝化脱氮的实验，探究了水力停留时间（HRT）对系统的协同脱氮效率、氮的中间产物、出水SO₄ ^2-浓度、FeCO₃自养反硝化的脱氮贡献率及微生物群落结构变化的影响。研究结果表明，当HRT=12 h时，系统总无机氮（TIN）去除率为95.67%，出水SO₄ ^2-质量浓度为181.26 mg/L，并且FeCO₃自养反硝化脱氮对氮脱除的贡献率增加至20.49%，该HRT条件下积累的中间产物和生成的SO₄ ^2-最少，是硫/菱铁矿组合系统适宜的运行条件。硫杆菌属（Thiobacillus）是系统中丰度最高的自养反硝化细菌，其利用硫和Fe（Ⅱ）作为电子供体降解NO₃ ^--N。硫/菱铁矿自养反硝化脱氮技术具有经济高效及协同脱氮的特点，这将使其成为一种极具潜力的污水处理厂尾水深度脱氮的新方法。

关键词: 硫/菱铁矿, 自养反硝化, 脱氮, 水力停留时间, 群落结构

Abstract:

A combined sulfur/siderite system was constructed for autotrophic denitrification experiment. The effects of hydraulic retention time（HRT） on the synergistic denitrification efficiency，nitrogen intermediates，SO₄ ^2- concentration of effluent，autotrophic denitrification contribution proportion of FeCO₃ and changes of microbial community structure were explored. The results showed that when HRT was 12 h，the total inorganic nitrogen（TIN） removal rate of the system was 95.67%，the SO₄ ^2- mass concentration of effluent was 181.26 mg/L，and the proportion of FeCO₃ autotrophic denitrification increased to 20.49%. The accumulation of intermediate products and the formation of SO₄ ^2- were the least under this condition，which indicated that HRT=12 h was the suitable operating condition for the combined system. Thiobacillus，the most abundant autotrophic denitrifying bacteria in the system，utilized sulfur and Fe（Ⅱ） as electron donors to degrade NO₃ ^--N. Sulfur/siderite autotrophic denitrification technology had the characteristics of economical，efficient and synergistic denitrification，which would make it a promising new method for deep denitrification of tailwater of municipal wastewater treatment plants.

Key words: sulfur/siderite, autotrophic denitrification, denitrification, hydraulic retention time, community structure

中图分类号: 

• X703.1