设计总说明: 本设计为15万m3/d污水处理厂的初步设计。每天的平均进水量为15×104m3/d,每天的最高进水流量为19.5×104m3/d。设计进水水质为:CODcr:≤370mg/L, BOD5:≤200mg/L,SS:≤360mg/L,NH3–N≤50 mg/L,TN:≤60 mg/L,TP:≤6 mg/L。设计出水水质:CODcr:≤100mg/L, BOD5:≤30mg/L, SS:≤30mg/L,NH3–N:≤25mg/L,TN:≤20mg/L,TP:≤2.0mg/L。34044
经过二级生物处理后,污水中的氮和磷难以达到排放要求的标准,需要进行脱氮除磷处理。所以,本设计运用的工艺是A2/O工艺,具有脱氮除磷效果。A2/O工艺处理系统里同时含有厌氧区、缺氧区、好氧区,能够做到同时降解有机物和脱氮除磷,该工艺简洁,方便,污泥沉降性能较好。原污水进入第一厌氧反应器,同时进入的还有从二沉池回流的活性污泥。该反应区将回流污泥中的磷释放;将部分含氮有机物进行氨化。在缺氧反应区,该反应区主要是进行脱氮。硝态氮经过混合液内循环从好氧反应区过来,循环的混合液较多,为原污水的2~4倍。在反硝化菌的作用下,部分有机物利用硝酸盐作为电子受体而被降解去除。混合液经过缺氧反应区处理,混合液进入好氧反应区,该反应区主要是进行硝化、磷吸收、去除BOD等。好氧区排放的污水,COD浓度已基本接近排放标准。在好氧反应区中的混合液硝态氮回流至缺氧反应区,污泥中过量的磷通过排出的剩余污泥排除。根据国内众多城市污水处理厂运行结果,A2/O工艺处理出水一般可达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的二级标准,能够确保城市周边水体的环境要求。
污水处理流程为:污水先是经过一级处理构筑物,通过中格栅后进入污水提升泵房,然后经过细格栅,曝气沉砂池,进入辐流式初沉池等;再通过二级处理构筑物,先是A2O生物反应池,然后经过辐流式二沉池,接触消毒池,在巴氏计量槽后,排入水体。污泥处理流程为:从反应池排出的剩余污泥通过污泥泵将集中输送到污泥浓缩池,再由剩余污泥泵送到污泥脱水房,然后外运处置。设计中,地面标高为0.00m,最高水位为12.058m。各类污染物的去除率为:CODcr为80%;BOD5为85%;SS为92%;NH3-N为84%;TN为67%;TP为83.3%。污水处理厂总投资费用为20928.78万元,处理成本为0.59元/吨。本设计对污水处理厂处理构筑物,处理流程,以及高程和平面布置进行了初步设计。
毕业论文关键词: 脱氮除磷;AAO工艺;工艺设计;污水处理
A certain activated sludge sewage treatment process design
Description:The method design for the 15×104 m3/d,wastewater treatment plant method
design.The average of daily water flow is 15×104m3/d, and the highest daily flow is 15×104
m3/d.The quality of influent water: CODCr is 370mg/L,BOD5is 200mg/L; SS is 360mg/L;
NH3-N is 50mg/L; TN is 60mg/L; TP is 6mg/L. Design out of water: CODCr is 100mg/L,
BOD5 is 30mg/L; SS is 30mg/L; NH3-N is 25mg/L; TN is 20mg/L; TP is 2mg/L.
Wastewater by way of the secondary biological treatment, N and P will hardly accomplish
standard, have to remove the N and P. Therefore, process the application process for the anaerobic anoxic oxic,has the effect of nitrogen and phosphorus removal. A2/O process in the treatment system has both the anaerobic, anoxic zone, aerobic zone, can simultaneously achieve degradation of organic matter and nitrogen and phosphorus removal, the process is simple, convenient and good sludge settling properties.Raw sewage into the first anaerobic reactor, while also entering returning from the secondary settling tank sludge. The reaction zone will return sludge phosphorus release; part of ammoniated nitrogen-containing organic compounds.In the anoxic reaction zone, the reaction zone is mainly for denitrification. After circulating within the mixture of nitrate from the aerobic reaction zone over mixture cycle more, 2 to 4 times the original wastewater. Some organic matter as an electron acceptor to obtain the removal of degradation under the action of denitrifying bacteria utilize nitrate.After the reaction mixture anoxic zone treatment mixture into the aerobic reaction zone, the reaction zone is mainly nitrification,absorb phosphorus removal and BOD.Aerobic sewage discharge area, COD concentration basically close emission standards. In the aerobic reaction zone a mixture of nitrate to anoxic reaction zone reflux, excess phosphorus sludge excess sludge discharged by the exclusion.According to the running effect of many inland urban wasterwater treatment plants, the exit water disposed by anaerobic anoxic oxic generally can reach the GB18918-2002"urban sewage treatment plant pollutant discharge standard" a second standard ,can guarantee the environment alrequire of the water body around. 每天15万立米活性污泥法处理生活污水的工艺设计+CAD图纸:http://www.youerw.com/huaxue/lunwen_31409.html