【作者】 邓旭亮；

【导师】 欧阳峰； 王爱杰；

【作者基本信息】 哈尔滨工业大学 ， 环境科学与工程， 2006， 硕士

【摘要】 本研究基于具有反硝化功能的自养硫氧化细菌可在厌氧条件下利用硫化物为电子供体、硝酸盐为电子受体进行代谢活动同时胞外生成单质硫的生理特性,利用定向驯化的活性污泥启动厌氧固定床生物膜——同步脱硫反硝化反应器,从而创造一个自养硫氧化/反硝化菌和异养反硝化菌共存的混养生态系统,通过二者的协同作用,实现对硫化物、硝酸盐和乙酸盐的同时去除以及单质硫的积累。通过在不同条件下的连续流运行,考察了混养条件下同步脱硫反硝化工艺的可行性,探讨了工艺运行的关键影响因素如pH值和硫氮比,并在此基础上确定了本工艺系统的最大处理负荷。结果表明:①混养条件下可获得了良好的硫化物、硝酸盐和乙酸盐的同步去除以及单质硫生成的效果,硫化物的毒性对系统中微生物没有明显的抑制作用;②混养条件下自养反硝化菌和异养反硝化菌是共生的关系。异养反硝化菌通过利用自养反硝化菌的代谢中间产物亚硝酸根,促进自养反硝化活动的进行,同时保证了工艺过程中单质硫的大量积累;③较低的偏碱性pH值条件有利于同步脱硫反硝化过程的进行,在较高的pH值条件下,单质硫产率较低;④硫氮比对工艺的运行效能影响显著,硫氮比为5/6时可获得最佳的硫化物去除和单质硫生成的效果;⑤工艺的最大处理负荷为2.4 kgS2-/m3d,该负荷条件下可获得100%的硫化物去除率和略高于2.4 kgS/m3d的理论单质硫产率。更高的负荷条件下,工艺的运行效能大幅度降低。结合试验结果,对同步脱硫反硝化过程的机理进行了探讨,并推导了该过程的反应计量式。混养同步脱硫反硝化工艺比单独自养时具有更佳的去除硝酸根的能力,是废水处理中一项经济高效的厌氧生物新技术。更多还原

【Abstract】 In this study, a laboratory-scale anaerobic fixed-bed bio-reactor was used to investigate the treatment performance and key factors of simultaneous de-sulfurization and de-nitrification process. Activated sludge was domesticated directionally to cultivate autotrophic sulfur-oxidizing/denitrifying bacterium, which are capable to oxidize sulfide to elemental sulfur when nitrate was adopted as electron acceptor under anaerobic or anoxic conditions and accumulate elemental sulfur extracellularly. Acetate was also added to incubate heterotrophic denitrificans. Thus, autotrophs and heterotrophs coexisted in the ecosystem, and cooperated to remove sulfide, nitrate and acetate simultaneously with elemental sulfur accumulation.The feasibility of simultaneous desulfurization and denitrification under mixotrophic condition was investigated via continuous-flow tests. Then key factors of the process, including pH value and sulfide/nitrate (S/N) ratio, were discussed. Under the optimum pH value and S/N ratio conditions, the volume loading rates were elevated until the treatment performance declined. The experimental results suggest:①The simultaneous removal of sulfide, nitrate and acetate as well as elemental sulfur accumulation could be achieved under mixotrophic condition. It was shown that the toxicity of sulfide had little inhibition on the functional microorganisms in this system.②The relation between autotrophic sulfur-oxidizing/denitrifying bacteria and heterotrophic denitrifiers was symbiotic. The heterotrophs could accelerate the autotrophic denitrification by utilizing its intermediate products, namely nitrite, which also ensured the accumulation of elemental sulfur.③Lower alkalescent pH condition was favorable to the SDD process. The theoretical S0 production rate was much lower under higher pH conditions.④S/N ratio had a remarkable influence on the treatment performance. The optimum S/N ratio to acquire the best efficiencies of both sulfide removal and elemental sulfur accumulation was supposed to be 5/6.⑤Complete sulfide removal and a theoretical elemental sulfur production rate of 2.4 kgS/m3d were achieved at a volume loading rate of 2.4 kgS2-/m3d. At higher loading rates, the efficiency deteriorated sharply. Based on these results, the更多还原