新型缓释碳源滤料的制备及其应用研究

发布时间：2017-12-31 07:22

本文关键词：新型缓释碳源滤料的制备及其应用研究　出处：《北京工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：城镇污水厂尾水中硝酸盐氮的浓度较高,污水回用前未经有效脱氮,会对城市景观绿化、道路洒水、河湖补给等再生水回用带来安全隐患。因此,污水深度脱氮成为目前再生水回用的关键问题。由于尾水中的C/N较低,再生水深度脱氮往往需外加碳源,传统液体碳源存在投加量不易控制,造成二次污染和脱氮不完全等问题,近年来制备性能优越、价格低廉的固相缓释碳源成为替代传统碳源的研究方向。本研究为了提高传统淀粉/聚乙烯醇(PVA)缓释碳源的反硝化速率,并有效控制碳源的释放速率、延长碳源使用周期,采用添加醋酸酯淀粉、疏水性乳化剂(SPAN80)以及内外部碳源相包裹、表层硼酸交联等方法,制备了新型缓释碳源,通过释碳和脱氮试验考察了缓释碳源的最佳材料配比、碳源释放规律以及脱氮工艺的运行特性,并通过高通量测序技术分析了脱氮工艺系统中的微生物群落结构。具体的研究结果如下:采用内、外部碳源相包裹,并辅以少量(5%)乳化剂(SPAN80)和硼酸交联等制备方法能有效地控制释碳速率,单位质量新型缓释碳源的释碳速率为0.034mg/(g·h);同时也提高了淀粉在缓释碳源中的比例(58.2%),有利于延长碳源使用周期;醋酸酯淀粉/PVA共混体系的反硝化速率比普通淀粉/PVA共混体系高5倍以上,新型缓释碳源的内部碳源制备采用醋酸酯淀粉/PVA共混体系,可提高整体缓释碳源的品质。在新型缓释碳源的外部碳源中添加一定比例的硫磺粉,能够制备出机械强度高和使用周期长的新型缓释碳源滤料,利用该缓释碳源滤料填充反硝化滤柱,对含硝酸盐的配水进行脱氮处理工艺研究,取得理想的脱氮效果,进水硝态氮在22~38mg/L时,其去除率可达100%;反硝化系统中碳源释放与利用基本平衡,出水COD稳定(平均21.54mg/L);系统对进水水量、水质的波动具有一定的适应能力,硝态氮去除负荷会自主响应进水水量、水质的波动,当停留时间为0.5h时,反应器的最高脱氮负荷达12.11mg/(L·h);该反硝化系统由于碳源水解酸化作用存在,能够中和反硝化所产生的碱度,出水p H稳定在中性范围(平均7.22);在反硝化系统碳源充足时,硫磺粉的自养反硝化作用不明显,进出水SO42-增量仅为0.05mg/L。新型缓释碳源滤料脱氮系统中主要微生物菌门为proteobacteria(变形菌门)、Bacteroidetes(拟杆菌门)和Firmicutes(厚壁菌门),三者相加所占微生物总量的比例大于90%;起反硝化作用的菌属均从属于proteobacteria(变形菌门),各菌属有:Dechloromonas、Zoogloea、Hydrogenophaga、Thauera、Sulfurospirillum、Pseudomonas、Sulfurimonas,以异养反硝化为主,同时存在硫自养反硝化和氢自养反硝化(氢自养反硝化的存在是因为碳源的水解酸化产生了CH4、H2等小分子物质)。而Bacteroidetes(拟杆菌门)和Firmicutes(厚壁菌门)主要起水解酸化缓释碳源的作用。本研究在缓释碳源材料选择、配比以及制备方法方面具有新颖性,制备出的新型缓释碳源滤料具有良好的脱氮性能和合理的脱氮成本;同时从微生物层面解析了新型缓释碳源滤料脱氮功能实现的内在规律。研究结果对于提高污水厂尾水深度脱氮技术水平具有一定的应用价值和指导作用。
[Abstract]:High concentration of municipal sewage plant effluent nitrate nitrogen in water and wastewater reuse before effective nitrogen removal, the city landscape greening, road watering, with hidden dangers to rivers and lakes supply of reclaimed water. Therefore, wastewater nitrogen removal has become a key issue of reclaimed water. From the tail water C/N low reclaimed water depth nitrogen often need additional carbon source of traditional liquid carbon source dosage is not easy to control, two pollution caused by nitrogen and incomplete, in recent years for superior performance, solid carbon source low price has become a research direction to replace the traditional carbon source. In this study, in order to to improve the traditional starch / polyvinyl alcohol (PVA) denitrification carbon source, and effectively control the release rate of the carbon source, prolong the service cycle of carbon source, by adding starch acetate, hydrophobic emulsifier (SPAN80) and the internal and external carbon source coating, surface to boric acid With the method, the new carbon source was prepared by carbon and nitrogen removal were investigated in the best material carbon source, carbon source and the operation characteristics of releasing regularity of nitrogen removal process, and through the high-throughput sequencing analysis and microbial community structure of nitrogen removal in the system. The results are as follows by using internal, external carbon source coating, supplemented with (5%) emulsifier (SPAN80) and boric acid crosslinking preparation method can effectively control the release rate of carbon, carbon release rate per unit mass of new carbon source for 0.034mg/ (g, H); at the same time also increased in carbon source in starch the proportion (58.2%), to extend the life cycle of carbon source; denitrification rate of acetate starch /PVA blends than ordinary starch blends of /PVA more than 5 times, the internal carbon source and new carbon source were prepared using acetate starch /PVA blends, can improve the overall Carbon source quality. Adding a certain proportion in the external carbon source of new carbon source in the sulfur powder can be prepared with high mechanical strength and long life cycle of the new carbon source material, filling denitrification filter column using the carbon source material, water containing nitrate nitrogen removal study on the nitrogen removal process, achieve the ideal, influent nitrate nitrogen at 22~38mg/L, the removal rate could reach 100%; carbon source denitrification system release and utilization of basic balance, stable effluent COD (average 21.54mg/L); system of water quantity, water quality fluctuation has a certain ability to adapt to the nitrate nitrogen removal load independent response to the fluctuation of water quality, water quantity, when the residence time is 0.5h, the highest nitrogen removal load of 12.11mg/ reactor (L - H); the denitrification system due to the presence of carbon source hydrolysis acidification, denitrification and alkalinity can produce water, P H Stable in neutral range (average 7.22); in the denitrification system abundant carbon source, sulfur autotrophic denitrification is not obvious, and out of the water SO42- growth of only 0.05mg/L. new carbon source material and main microbial nitrogen door system for Proteobacteria (Proteobacteria), Bacteroidetes (Bacteroidetes) and Firmicutes (Firmicutes), three sets of the total of microorganisms ratio greater than 90%; from denitrification bacteria from belonging to Proteobacteria (Proteobacteria), the genus: Dechloromonas, Zoogloea, Hydrogenophaga, Thauera, Sulfurospirillum, Pseudomonas, Sulfurimonas, with heterotrophic denitrification, and sulfur autotrophic denitrification and hydrogen autotrophic denitrification (hydrogen autotrophic denitrification exists because of hydrolysis and acidification of carbon source in the CH4, H2 and other small molecules). And Bacteroidetes (Bacteroidetes) and Firmicutes (Firmicutes) mainly Hydrolysis acidification release carbon source. This study on carbon source materials, novel formula and preparation method, preparation of a new type of carbon source nitrogen removal filter has good performance and reasonable cost at the same time from microbial denitrification; analyzes the inherent law of the new slow release carbon source material removal to realize the function of nitrogen. The results have certain application value for improving the level of nitrogen removal and guidance technology of tail water sewage factory.

【学位授予单位】：北京工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703

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