进水氨氮对厌氧同步脱氮除硫工艺的影响

通过比较含氨氮和不含氨氮两种进水水质条件下接种物不同的两个反应器的脱氮除硫特性,研究进水氨氮对厌氧同步脱氮除硫性能的影响。结果表明,进水未加氨氮的反应器对硫化物和硝态氮的去除率均高达95%,当加入氨氮后,仅有40%～50%的硝态氮被去除,消耗1 g硫化物所还原的硝态氮量减少,去除硝态氮的能力降低了近50%,然而对硫化物的去除率仍维持在90%左右,表明脱氮过程比脱硫过程受进水氨氮的影响大。扫描电镜观察结果证实,当进水中存在氨氮时硫化物的毒性增大,杀死了大量的脱氮硫杆菌,降低了硫化物转化为单质硫的能力,干扰了系统的反硝化脱氮过程,这是导致体系脱氮能力降低的主要原因。

Effect of Influent Ammonia Nitrogen on Simultaneous Desuifurization and Denitrification

The desulfurization and denitrification characteristics of two anaerobic reactors using different inocula and influents with and without ammonia nitrogen were compared to investigate the effect of influent ammonia nitrogen on simultaneous desulfurization and denitrification.The removal rates of sulfide and nitrate nitrogen were up to 95% in the reactor using influent without ammonia nitrogen.After addition of ammonia nitrogen,the removal rate of nitrate nitrogen was decreased to 40%-50%,the amount of nitrate nitrogen reduced by 1 g of sulfide was sharply decreased,and the removal capacity of nitrate nitrogen was lowered by 50%.However,the removal rate of sulfide was still maintained at 90%,showing that the influent with ammonia nitrogen had more influence on denitrification than desulfurization.The results of scanning electron microscope(SEM) indicated that the toxicity of sulfide was increased when ammonia nitrogen existed in influent,which killed a lot of Thiobacillus,reduced the conversion ability of sulfide into elemental sulfur,and interfered with the denitrification process.All these are major causes leading to decrease in denitrification ability of the system.