关键词：厌氧发酵；ASBR；SBR；高浓度有机废水；有机负荷；去除率
Study on the Efficiency of ASBR-SBR Process for the
Concentrated Wastewater Treatment
Abstract
With the development of stockbreeding industry, production of dung of animal waste as a reliable energy resource is a promising technology to deal with these problems. Anaerobic sequencing batch reactors (ASBR) can get shorter time (HRT) which means smaller reactor needed and better economic effect, and keep longer solid retention time (SRT). As other anaerobic treatment technology, ASBR can not remove nitrogen, so sequencing batch reactor (SBR) is added.
In this thesis four aspects are studied. The first one is the study on the treatment of the treatment of organic wastewater by ASBR at different temperature. The third one is the study on the treatment of organic wastewater with ASBR at room temperature. The last one is the study on the treatment of organic wastewater with ASBR-SBR at 35℃. The effect of factors on the index is analysed. The following conclusions are achieved.
1. Study on the different organic loading rate (OLR) with ASBR at 35℃. The results indicate that optimal effects are achieved when the OLR is 6gVS(L·d), the volume gas productivity is 2.09 L(L·d), VS gas productivity is 0.35LgVS, the removal of COD and SCOD are 33.74% and 70.43%, the removal of TS and VS are 31.16% and 34.46%, the content of CH4 in biogas is 82.10%.
2. Study on the three different influent concentrations with ASBR at 35℃. The results indicate that when the influent concentration is 46gVSL and 61.2gVSL, the biogas yield is almost the same. Compare the removal of COD and SCOD, the formal is better, but the latter one achieves the better removal of TS and VS.
3. Study on the three different churn up fashion with ASBR at the OLR of 6gVS(L·d) at 35℃. The results indicate that the removal of VS is lower when churn up fashion is 3min the other items. Because of the longevity of the gas pump, the fashion of 1.5min30min is choosed.
4. the effect of treatment of dairy wastewater with ASBR at 35℃、30℃、25℃ and 21℃ is studied. The removals of all items at 30℃ are adjacent to those at 35℃. The removals of all items at 21℃ are better than those at 25℃ except the SCOD. In view of low energy and better treatment effect, the optimal temperature is 30℃. And if just considering the lower energy cost, 21℃ is the optimal temperature.
5. Study on three different OLR with ASBR at 21℃, from 4 to 6gVS(L·d). The results indicate that when the OLR is 5gVS(L·d), the gas yield is best and the treatment effect is better. the gas productivity、VS gas productivity and volume gas productivity are all the best, they are28.12Ld、0.18gVS(L·d) and 1.08L(L·d). the PH is maintained at 7.02, the content of CH4 in biogas is the the three different churn up fashion with ASBR at the OLR of 6gVS(L·d) at 21℃. The results indicate that the removal of TS and VS is lower when churn up fashion is 3min the other items. Because of the longevity of the gas pump, the fashion of 1.5min30min is choosed.
7. The OLR of ASBR is 6gVS(L·d) and the SBR is supplied discontinuously. The treatment of dairy wastewater with ASBR-SBR technics studied. The results show that ASBR is quite suit to the removal of organic, and SBR can achieve obvious effect of biological denitrification. ASBR-SBR technics can get , the removal of COD and SCOD are 58.72% and 73.22%, respectively. The removal of NH3-N achieves 94.37%, the content of NO2-N and NO3-N in the effluent are perfect.
Key words: anaerobic fermentation; ASBR; SBR; organic wastewater; organic loading rate; removal rate
Candidate: ×××
Speciality: Transformation and Utilization of Biobass Engineering
Supervisor: Prof.×××
1 引言
1.1 研究的目的和意义
能源是人类生存和发展的重要物质基础，生产力的发展和能源有着极为密切的关系，因此能源问题是现实社会中一个具有战略意义的重要问题。
自从进入20世纪，世界能源消费增长很快，1900年全世界能源的总消费量相当于7.75亿吨标准煤，到1980年就达到了大约100亿吨标准煤。从能源结构来看，20世纪60年代以前大量应用的能源是煤、石油、天然气。由于石油的开发和利用，60年代石油用量急剧增加，在20世纪70年代末，石油和天然气的消耗量接近全世界能源消耗总量的70%左右。世界已探明的石油储量约为3000亿吨，按现在每年开采40亿吨的水平计算，现有储量只够开采70年。煤的可开采储量为6800亿吨，以目前每年消耗煤炭35亿吨计算，可供全世界使用200年。煤、石油、天然气等常规能源日趋枯竭，开发、研究新能源已是世界各国亟待解决的问题。
我国是能源资源严重短缺的国家。石油、天然气人均剩余可采储量仅有世界平均水平的7.7％和7.1％，储量比较丰富的煤炭也只有世界平均水平的58.6％。按目前探明储量和开采能力测算，我国煤炭、石油、天然气的可采年限分别只有80年、15年和30年，而世界平均水平分别是230年、45年和61年。一个国家的国民生产总值和能源消耗量大致成线性关系，按21世纪前50年内国民经济总产值翻两番的构想和专家的预测，到2050年我国能源的总需求量大约是50亿吨标准煤，而我国的能源资源和生产能力大致只能提供总需求量的80%左右。近年来能源消费急剧增长，供需矛盾日益突出，已经成为我国经济持续发展的最大制约，直接威胁国家经济安全。发展新能源和新能源转化技术对我国经济建设是一个非常重要的课题。
