广东工业大学环境工程专业毕业设计 摘要
摘 要
我国水体污染主要来自两方面，一是工业发展超标排放工业废水，二是城市化中由于城市污水排放和集中处理设施严重缺乏，大量生活污水未经处理直接进入水体造成环境污染。工业废水近年来经过治理虽有所减少，但城市生活污水有增无减，占水质污染的51%以上。目前，东莞市道滘镇全镇面积54.41平方公里，常住人口54252人，外来人口86933人。由于经济迅速发展，特别是工业的不断投入，使得水体受到严重污染，为了改善人民的生活环境，政府大力投入资金，改变现今水体的水质。
本设计要求处理水量为30000m3/d的城市生活污水，设计方案通过比较已运行稳定有效的多种城市生活污水处理工艺的成功经验结合自身区域特点，采取了最为有效的处理工艺——A/A/O活性污泥法工艺（即厌氧－缺氧－好氧活性污泥法），是在A2/O除磷工艺基础上增设了一个缺氧池，并将好氧池出流部分混合液回流至缺氧池，A2O工艺由于不同环境条件，不同功能的微生物群落的有机配合，加之厌氧、缺氧条件下，部分不可生物降解的有机物（CODNB）能被开环或断链，使得N、P、有机碳被同时去除，并提高对CODNB的去除效果。它可以同时完成有机物的去除，硝化脱氮、磷的过量摄取而被去除等功能，脱氮的前提是NH3－N应完全硝化，好氧池能完成这一功能，缺氧池则完成脱氮功能。厌氧池和好氧池联合完成除磷功能。且从整体方面看来，整个工艺流程布局合理，废水治理成本低，虽有占地面积大这一不足，但通过对道滘镇的实际情况进行分析，本工艺设计还是比较理想。
本工艺的技术关键之一是合理确定进水分配系数a和b，而a和b是根据进水水质和出水水质确定的，如果a过少，则C/N过低，影响反硝化效果；如果a过大，则b过少，使C/P过低，影响除磷效果。因此，可根据实际进水水质调节a和b，以实现除磷的最佳效果。当污水处理要求不高时，可以实现减少混合液内循环量，减低能耗，使出水水质达到《广东省地方标准—水污染物排放限值》（DB44/26-2001）标准的要求。
关键词：城市生活污水，活性污泥，A2O
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广东工业大学环境工程专业毕业设计 摘要
Abstract
Water pollution mostly came from both sides in China. It is over proof effluent water from industry to one. It is urbanize course measure domestic sewage for by getting direct entry water substance done up to the second one. In recent years, industrial effluence has got be reduced by, none the less municipal sewage has got increased without subtract, and the 51% upwards of the occupy water pollution. Now, Daojiao town has got a locally domiciliary register population of 54252, an emigrate population of 86933, Daojiao government pump into vigorously, in order to ameliorate demotic living environment and transfer now that water substance water quality.
This design request processing water volume was the 30000m3/d city life sewage, the
design proposal moved the stable effective many kinds of city life sewage treatment craft success experience through the comparison to unify own region characteristic, has adopted the most effective processing craft - - A/A/O active sludge law craft ( aerobic - depleted oxygen -good oxygen). Was additionally built an oxygen deficit pond in A2/O except the phosphorus craft foundation in, and left the good oxygen pond flows the partial intermixture backflow to the oxygen deficit pond, the A2O craft because the different environmental condition, the different function microflora's organic coordination, added it to tire of the oxygen, under the oxygen deficit condition, the part might not biodegradation organic matter (CODNB) be able by the split-ring or the stopped chain, causes N, P, the organic carbon also to remove, and enhanced to CODNB? elimination effect. It may simultaneously complete the organic matter the elimination, the nitration denitrogenation, the phosphorus excessive ingestion is removed and so on the functions, the denitrogenation premise is NH3--N should the complete nitration, the good oxygen pond can complete this function, the oxygen deficit pond completes the denitrogenation function.Tires of the oxygen pond to become reconciled the oxygen pond to complete jointly eliminates the phosphorus function. Look like from the overall aspect, the technical process layout is reasonable. The waste water government cost is low, although it the area big this shortcoming. Through carries on the analysis to Daojiao town’s actual situation, this technological design quite is ideal.
One of this craft technical key is determined reasonably. The moisture content
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广东工业大学环境工程专业毕业设计 摘要
disposition system counts a and b, but a and b are according to enter the water quality and the water leakage water quality determination; If an oversized, then b too few, causes C/P excessively is low, the influence eliminates the phosphorus effect. Therefore, may enter the water quality according to the reality to adjust a and b, realizes eliminates the phosphorus the desired effect. When sewage treatment request not high, may realize the reduced intermixture internal recycling quantity, decreases the energy consumption. Selects improvement inverts A/A/O active sludge law, enables the water leakage water quality to achieve “Guangdong Province Place Standard - Water pollution Emissions Limiting value” (DB44/26-2001) standard request.
Keywords: municipal sewage, activated sludge, Anaerobic-Anoxic-Oxic
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