Cai Jing, Zheng Ping, Mahmood Qaisar
Department of Environmental Engineering, Zhejiang University, Hangzhou, China.
Bioresour Technol. 2008 Sep;99(13):5520-7. doi: 10.1016/j.biortech.2007.10.053. Epub 2007 Dec 18.
Present investigation deals with the effect of sulfide to nitrate (S/N) molar ratio on the simultaneous anaerobic sulfide and nitrate removal on capacity, stability and selectivity of the process. The volumetric sulfide-sulfur and nitrate-nitrogen removal rates at molar S/N ratio of 5:2 were 4.86 kg(m(3)d)(-1) and 0.99 kg(m(3)d)(-1), respectively, which were higher than those at S/N molar ratios of 5:5 and 5:8. Moreover, the fluctuations in the effluent at S/N ratio of 5:2 were less than those at the other two tested ratios. During the operation, the ratio of converted sulfide to converted nitrate tended to approach 5:2. The selectivity for elemental sulfur and dinitrogen was improved when the S/N molar ratio was set at 5:2 rather than 5:5 or 5:8. The process became unstable if the influent sulfide surpassed its critical concentration. The electron balance between reactants was also analyzed for different S/N molar ratios.
目前的研究涉及硫化物与硝酸盐（S/N）摩尔比对同步厌氧去除硫化物和硝酸盐过程的容量、稳定性和选择性的影响。在S/N摩尔比为5:2时，硫化物-硫和硝酸盐-氮的体积去除率分别为4.86 kg(m³d)⁻¹和0.99 kg(m³d)⁻¹，高于S/N摩尔比为5:5和5:8时的去除率。此外，S/N比为5:2时出水的波动小于其他两个测试比例时的波动。在运行过程中，转化的硫化物与转化的硝酸盐的比例趋于接近5:2。当S/N摩尔比设定为5:2而不是5:5或5:8时，对元素硫和氮气的选择性得到提高。如果进水硫化物超过其临界浓度，该过程会变得不稳定。还分析了不同S/N摩尔比下反应物之间的电子平衡。
