碳源对反硝化脱硫工艺碳氮硫同步脱除效果的影响

Effect of carbon resource on the operational performance of denitrifying sulfide removal process

摘要:

针对碳源对反硝化脱硫工艺运行效能影响不明问题, 实验采用UASB反应器, 考查两种不同碳源(乙酸钠和苯酚)条件下反硝化脱硫工艺碳氮硫去除效果及单质硫累积率, 在此基础上, 通过批次试验进一步探究碳氮硫降解及转化规律.结果表明：乙酸钠为碳源, HRT为2.5~10 h, NO₃^--N、S^2-和Ac^--C去除率分别保持在93%、90%和99%以上, 单质硫积累率稳定在41%以上；而苯酚为碳源, HRT为10 h, NO₃^--N、S^2-和C₆H₅O^--C去除率分别达67%、85%和50%, 但硫化物均转化为硫酸盐, 无单质硫累积.批次试验表明, 乙酸钠为碳源时, S^2-氧化速率(q_S^2-) > 乙酸盐氧化速率(q_Acetate) > S⁰的氧化速率(q_S⁰)；而苯酚为碳源时, S^2-氧化速率(q_S^2-) > S⁰的氧化速率(q_S⁰) > 苯酚氧化速率(q_Phenol), 从而使得硫化物的氧化产物有所差异.

Abstract:

In order to study the effect of carbon resources on the operational performance of denitrifying sulfide removal process, the removal efficiency of sulfide, nitrate and organic carbon was investigated in UASB reactor, using sodium acetate and phenol as the carbon resources respectively. Meanwhile batch cultivation experiment was applied to study the degradation and conversion of carbon, nitrate and sulfide. The results showed that the removal efficiency of NO₃^--N, S^2-and Ac^--C would reach 93%, 90% and 99% under a 2.5-10 h HRT, respectively, using sodium acetate as carbon source. Under such condition the accumulation rate of elemental sulfur remained stable at about 41%. For a comparison, the removal efficiency of NO₃^--N, S^2- and C₆H₅O^--C was 67%, 85% and 50% respectively using phenol as carbon resource (10 h HRT), however the sulfide was converted to sulfate completely and no elemental sulfur accumulated. The results of batch cultivation experiment showed that the oxidation rates of S^2-, acetates and S⁰ displayed in such order: q_S^2- > q_Acetate > q_S⁰ when the sodium acetate was used as carbon resource; however, the oxidation rates of S^2-, phenol and S⁰ using the phenol as carbon resource distributed in the trend of q_S^2- > q_S⁰ > q_Phenol.