【作者】 李栋；

【导师】 曹国民；

【作者基本信息】 华东理工大学 ， 环境科学与工程， 2011， 硕士

【摘要】 山东省章丘市村镇地下水普遍存在硝酸盐浓度过高的现象,这对当地居民的饮用水安全构成了极大威胁,将地下水中硝酸盐浓度降到安全水平显得尤为重要。本课题结合固定化细胞技术与膜技术,构建新型膜生物反应器,脱除地下水中的硝酸盐。首先,以脱氮效果为主要指标,对固定化细胞膜的制备条件进行了探索；然后,构建新型膜生物反应器,采用两种不同模式,探索碳源种类、C/N、初始硝态氮浓度、温度、pH等条件对脱氮效果的影响；再者,考察了碳源投加方式的改变及碳源重复利用对反硝化的影响；最后,对反应器两种不同模式的脱氮性能进行了比较,并评估了固定化细胞膜的使用稳定性。研究结果表明：(1)固定化细胞膜适宜的制备条件为细菌接种量2%(w/v)、膜的厚度4mm、冷冻-解冻次数4次；(2)乙醇为较适宜的反硝化碳源,硝酸盐降解速率与C/N、初始硝态氮浓度及温度正相关,适宜的脱氮条件为C/N=8、T=30℃、pH=7-8；(3)采用分批投加碳源的方式可以有效降低亚硝酸盐与CODMn的积累,碳源重复利用可以节约外加碳源的消耗；(4)新型膜生物反应器的两种不同模式在脱氮效果方面各有优劣,固定化细胞膜具有较好的使用稳定性及较长的使用寿命。更多还原

【Abstract】 The nitrate concentration is generally high in the groundwater of Zhangqiu City, Shandong province. It poses a threat to drinking water safety of local residents. So it is especially important to reduce the nitrate concentration to the safe level.The immobilized-cell process and membrane filtration process was combined together in this research, and a new membrane bioreactor was developed for removing nitrate from groundwater. First, the making conditions of immobilized-cell membrane were explored. Second, two new membrane bioreactors were designed and constructed, and the effect of carbon source types, C/N, initial nitrate concentration, temperature and pH on denitrification process were investagted in these two bioreactors. Then, the effect of carbon source dosing manner and residual carbon source reusing on denitrification were studied. Finally, the denitrification performance of the two different operation modes was compared, and the stability of immobilized-cell membrane was evaluated.The results showed:(1)The suitable making conditions of immobilized cell membrane were 2%(w/v)of bacterial inoculum,4mm of membrane thickness,4 times of frozen-thawed cycle; (2) Ethanol is a suitable denitrification carbon source. The degradation rate of nitrate is proportional to C/N, initial nitrate concentration, temperature(10℃-30℃), and the suitable C/N ratio, temperature, pH value are 8,30℃and 7-8, respectively; (3) Relative to the single dose of external ethanol, the two-dose supplementation produced better treatment results as evidenced by the lower concentrations of NO2--N and ethanol (as measured by CODMn) of the effluent, and for saving carbon source the residual carbon source could be reused; (4)The two different modes of the new membrane bioreactor showed different advantages during denitrification processes, and the operational system remained stable for about 10 months.更多还原