【作者】 邹贞；

【导师】 张永明；

【作者基本信息】 上海师范大学 ， 环境科学， 2009， 硕士

【摘要】 随着城市化的发展,许多城市的河道、湖泊等水体都受到了污染,不仅氮、磷超标引起富营养化,而且还受到了难降解有机物的污染,表现为复合污染与低碳氮比的特征。对于这类复合污染水体,采用单一物理、化学或生物等方法,都难以修复或控制。鉴于这种情况,我们研制一种集光催化与生物降解一体化的反应器,分别对模拟和实际的复合污染水体进行处理。实验首先研制了TiO₂光催化膜的制备方法,确定使用TiO₂溶胶-凝胶法制备的光催化板是具有催化氧化效果的,并确定载体为玻璃,镀膜8次,在500℃左右下煅烧时,所得的光催化薄膜具有最佳的催化氧化效果。其次,实验采用TiO₂光催化剂对受到复合污染的城市河道水进行处理,发现水中的COD出现大幅升高的现象。通过对吡啶进行光催化氧化,验证了其COD上升的原因,并结合紫外分光光谱分析,发现其结构发生变化,由最初不能被重铬酸钾氧化转变为可以被氧化,其COD先逐步升高后又下降,从而说明城市复合污染水体中存在类似的有机物。在采用光催化氧化和生物降解一体式反应器对该水体进行修复过程中,水中的总氮和COD呈现相对变化的关系,即当COD变化率为负值时,TN的变化率则基本为正值。反之COD变化率为正值时,TN的变化率则基本呈负值。结果表明在光催化氧化和生物降解的协同作用下,总氮和有机物得到同步去除。最后进一步的反硝化实验中又发现,水中这些有机物污染物在经过光催化氧化之后,可以转变为容易被微生物所利用的有机碳源,从而提高水中的碳氮比。实验证明,经过光催化氧化处理后的河道水,其总氮去除率比未经过光催化氧化的河道水提高30%以上。更多还原

【Abstract】 With the development of urbanization, many rivers and lakes are polluted simultaneously by nitrogen,phosphate and recalcitrant chemicals. For this kind of water, it is difficult to get repaired by complying single physical, chemical, or biological methods.In this case,we treat the simulated and actual water with complex pollution by using integrated photocatalytic-biological internal circulating reactor.At the beginning of the research, we study the method of TiO₂ sol-gel for making TiO₂ film, and the effect of photocatalytic film. The results show that the best film should be coated on groundglass,for eight times, in 500 degrees Celsius.In the study of groundwater（composite polluted） treatment by TiO₂ photocatalyst, we found that COD could be increasing greatly, and we get the same result in the photocatalytic treatment of water containing pyridine, which indicates that the urban river water contains the similar chemicals like pyridine. The structure of pyridine was changed after photocatalytic oxidation according to ultra violet spectrum analysis. Verified the rise of COD ,and original pyridine could not be oxidized by potassium dichromate, but it could be oxidized after photocatalytic oxidation. Experimental results suggested that there were some recalcitrant organics in urban river water with complex pollution.It can be indicated that the change of TN was relative to the change of COD. The removal rate of COD was opposite to the removal rate of TN, by using integrated photocatalytic-biological internal circulating reactor.TN and chemicals are removed at the same time by integrated photocatalytic-biological internal circulating reactor.After photocatalytic oxidation,the chemicals might be transferred into utilizable organic carbon source uses by microorganism and increase of carbon/nitrogen ratio. It is indicated that total nitrogen removal rate increased more than 30 percent by photocatalytic oxidation compared with the river treat that without photocatalysis.更多还原