改良SBR法同步硝化反硝化处理农村生活污水研究

发布时间：2018-06-06 00:53

本文选题：改良SBR法 + 同步硝化反硝化　；参考：《东北农业大学》2017年硕士论文

【摘要】：近年来,我国在城市污水治理方面取得长足进步,但在农村污水治理方面处于刚刚起步阶段。我国农村生活污水来源于日常生活用水、堆放垃圾产生的渗滤液、小规模养殖过程中产生的污水,具有污染物浓度较低变化大、污水量较小、配套污水处理设施发展相对迟缓等特点。由于缺少对农村生活污水的有效控制和管理,导致大量未经处理的农村生活污水随意排放,严重影响了农村居民的生产和生活。污水中氮磷排放是导致水体富营养化的重要原因,必须加以控制。农村具有污水产生量相对较小、经济基础薄弱及农村管理人员缺乏及技术水平相对较低等状况,研发适于农村生活污水处理的技术,高效低耗地去除农村生活污水中的污染物,对于改善农村生态环境、促进农村可持续健康发展具有重要意义。序批式活性污泥法(SBR)具有污泥活性强、耐冲击负荷强、运行费用低、污染物去除率高等优点。本研究通过自主设计新型SBR反应器,通过改变其曝气方式,考察了温度、污泥龄及溶解氧对COD和氨氮去除效果的影响,稳定实现了同步硝化反硝化(SND)过程,并通过高通量测序对系统内微生物多样性进行了分析。曝气时间、污泥龄(SRT)、温度和溶解氧(DO)对污染物的去除效果影响较大。随着曝气时间的延长,NH4+-N和COD浓度均呈现逐渐下降的趋势,在240min时基本稳定。随着污泥龄从10d延长到25 d,NH4+-N、COD及TN的去除效果逐渐增强,在污泥龄为20 d时去除效果最佳,NH4+-N、COD及TN的平均去除率分别为95.04%、98.24%、69.05%。胞外聚合物松散层中多糖和蛋白质的含量随污泥龄的延长均呈现先增大后减少的趋势。而胞外聚合物紧密层中多糖含量较稳定无明显变化,蛋白质含量变化趋势与松散层一致。温度影响污染物的去除效果及胞外聚合物的含量。当温度为25℃时,NH4+-N、COD及TN的平均去除率分别可达97.76%、91.27%、68.76%。温度从25℃降低至10℃时,NH4+-N、COD及TN的平均去除率分别降低了31.52%、10.74%、15%;低温导致胞外聚合物松散层中多糖含量增加了11.1 mg/g,蛋白质含量减少了6.15 mg/g。比较而言,温度的降低对松散层组分含量的影响大于总胞外聚合物及紧密层。溶解氧浓度对COD及NH4+-N去除效果影响不大,但对同步硝化反硝化效果影响较大。当主反应区溶解氧从1.0-1.5 mg/L降低至0.5-1.0 mg/L,COD平均去除率从86%降低至80%,NH4+-N平均去除率从98.89%降低至95.09%;而TN平均去除率由64.6%升高至72.58%,同步硝化反硝化率由65.94%升高至75.5%。胞外聚合物的含量及其中多糖和蛋白质含量均随着溶解氧浓度的降低而减小。通过对SBR系统内微生物多样性进行分析可知,群落结构多样性及物种丰富度均较高。系统内存在大量能降解有机污染物的异养菌群如Saccharibacteria和Zoogloea,还存在具有反硝化能力的菌群如陶厄氏菌(Thauera)及具有潜在硝化反硝化能力的菌群Cytophagaceae、黄杆菌(Flavobacterium),在微生物的作用下,污水中的污染物得以高效去除。
[Abstract]:In recent years, China has made great progress in the treatment of urban sewage, but it is in the beginning stage in the treatment of rural sewage. The rural domestic sewage is derived from the daily living water, the leachate produced by the waste of waste, the sewage produced in the small scale breeding process, with the low concentration of pollutants, the small amount of sewage and the matching of the sewage. The development of sewage treatment facilities is relatively slow. Due to the lack of effective control and management of rural domestic sewage, a large amount of untreated rural sewage is discharged at will, which seriously affects the production and life of rural residents. The nitrogen and phosphorus emission in the sewage is an important cause of the eutrophication in the water body and must be controlled in the countryside. It is of great significance to improve the rural ecological environment and promote the sustainable and healthy development of rural areas with the relatively small amount of sewage production, the weak economic base, the lack of rural management personnel and the relatively low technical level, and the research and development of the technology suitable for rural sewage treatment and the efficient and low consumption of the pollutants in rural domestic sewage. The sequencing batch activated sludge process (SBR) has the advantages of strong sludge activity, strong impact load, low operating cost and high removal rate of pollutants. This study investigated the effect of temperature, sludge age and dissolved oxygen on the removal of COD and ammonia by changing its aeration mode by independently designing a new type of SBR reactor, and stabilized the simultaneous nitrification and anti nitration. SND process, and through high throughput sequencing analysis of microbial diversity in the system. Aeration time, sludge age (SRT), temperature and dissolved oxygen (DO) have great influence on the removal of pollutants. With the prolongation of aeration time, the concentration of NH4+-N and COD decreases gradually, and is basically stable at 240Min. With sludge age from 10D The removal efficiency of 25 D, NH4+-N, COD and TN increased gradually, and the removal efficiency was best at the age of 20 d. The average removal rates of NH4+-N, COD and TN were 95.04%, 98.24% respectively. The content of polysaccharide and protein in the loose layer of extracellular polymers of 69.05%. increased first and then decreased with the age of sludge. There is no obvious change in the content of polysaccharide in the layer, and the change trend of protein content is the same as that in loose layer. Temperature affects the removal effect of pollutants and the content of extracellular polymers. When the temperature is 25, the average removal rate of NH4+-N, COD and TN can reach 97.76%, 91.27%, and 68.76%. temperature from 25 degrees to 10 degrees C, NH4+-N, COD and TN The removal rates were reduced by 31.52%, 10.74% and 15% respectively. At low temperature, the content of polysaccharide in the loose layer of extracellular polymer increased by 11.1 mg/g, and the decrease of protein content was 6.15 mg/g.. The effect of temperature reduction on the content of the loose layer was greater than that of the total extracellular polymer and the close layer. The dissolved oxygen concentration had little effect on the removal of COD and NH4+-N. When the dissolved oxygen was reduced from 1.0-1.5 mg/L to 0.5-1.0 mg/L in the main reaction zone, the average removal rate of COD decreased from 86% to 80%, the average removal rate of NH4+-N decreased from 98.89% to 95.09%, while the average removal rate of TN increased from 64.6% to 72.58%, and the rate of simultaneous nitrification and denitrification increased from 65.94% to the extracellular polymer of 75.5%.. The content and the content of polysaccharide and protein decreased with the decrease of the concentration of dissolved oxygen. Through the analysis of microbial diversity in the SBR system, the diversity of the community structure and species richness were higher. There were a large number of heterotrophic bacteria groups such as Saccharibacteria and Zoogloea that could degrade organic pollutants. Nitrifying bacteria such as Thauera, Cytophagaceae and Flavobacterium, which have potential nitrification and denitrification ability, are effectively removed from the wastewater under the action of microbes.
【学位授予单位】：东北农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X799.3

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