【作者】 沈雨；

【导师】 黄勇；

【作者基本信息】 苏州科技学院 ， 环境工程， 2010， 硕士

【摘要】 目前较多的分散污水处理工艺尽管在很多地区得到了应用,但是很多弊端也日益显现出来,尤其存在占地面积大、设备复杂等缺点。而本研究课题主要针对分散污水处理工艺存在的一些问题,设计开发出了气升回流一体化反应装置,主要用于处理分散生活污水,旨在获得最佳运行工况和设计参数,实现污染物的达标排放,便于实际工程推广和应用。本研究采用总有效容积为95L的气升回流一体化反应器,对实际分散生活污水进行了初步研究。主要研究了混合液回流比和污泥负荷等对工艺整体运行性能的影响。研究结果如下:(1)在回流比为1.2左右,沉淀区无污泥回流到缺氧区,只有出水回流,COD污泥负荷为0.25 kgCOD/(kgMLSS·d),平均水温为13.9℃,系统出水COD、氨氮和硝氮浓度分别为52mg/L、2.5mg/L、17.2mg/L平均去除率分别为86.4%、89.8%和23.7%。出水浊度由3.1 NTU逐渐升高到22.8NTU左右,好氧区无污泥回流到缺氧区,反硝化效果较差。(2)混合液回流比增加到3左右,沉淀区的污泥顺利回流到缺氧区。系统水温在一段时间较为稳定,出水COD、NH3-N和TN平均浓度分别从49mg/L、2.5mg/L和19.0mg/L降为42mg/L、1.1mg/L和5.0mg/L,平均去除率分别从88.2%、90.3%和24.9%增加为89.5%、96.3%和83.7%,在水温降到4.5℃时,NH3-N和TN去除率明显降低。(3)在污泥负荷为0.30 kgCOD/(kgMLSS·d)左右,气水比为30:1,并稳定运行后,好氧区的污泥沉降性能较好,SVI值在110左右。出水COD、NH3-N和TN平均出水浓度分别为33.3mg/L、1.8mg/L和5.9mg/L,平均去除率分别为92.5%、95.5%和83.7%,出水可达GB18918-2002一级A标准。出水浊度平均为3.4NTU。COD污泥负荷增加到0.49 kgCOD/(kgMLSS·d)以上时,发生了污泥膨胀现象,SVI值从68增加到363,好氧区的污泥浓度较低,沉淀区污泥随出水流失。这也表明,污泥负荷为0.30 kgCOD/(kgMLSS·d)左右有利于系统的稳定运行。更多还原

【Abstract】 Nowdays,although more decentralized wastewater treatment processes have been applied in many areas,there were also many shortcomings such as larger area,complex equipment and so on.This thesis aimed at shortcomings above-mentioned,an airlifting-reflux combined reactor was developed mainly for treating decentralized wastewater in order to obtain optimum operating conditions,design parameters, meet the discharge standard and application of practical engineering.In this thesis , the reactor devices with 95L total effective volume,11.2h HRT, 200L/d handling capacity was carried out to conduct preliminary study.Major objectives were pollutant removal efficiency,reflux ratio,the volume ratio of reaction zones,sludge reduction and so on.The main results were presented as follows:(1) when reflux ratio was1.2,COD-sludge load was 0.27kgCOD/(kgMLSS·d)sludge in the aerobic zone was not return to the anoxic zone,only effluent after precipitation was returned,the average temperature was 13.9℃.The average effluent COD、ammonia and nitrate concentrations were 52mg/,2.5mg/L and 17.2mg/L respectively , average removal rates were 86.4% , 89.8% and23.7% respectively.Effluent turbidity was gradually increased to 22.8NTU from 5.3 NTU.(2) When reflux ratio increased to about 3,the sludge in settling zone was smoothly returned to the anoxic zone.water temperature was stable.The average effluent COD,NH3-N and TN concentrations were rfrom 49mg/L,2.5mg/L and 19.0mg/L reduced to 42mg/L,1.1mg/L and 5.0mg/L respectively,the average removal rate were from 88.2%,90.3%,and 24.9% increased to 89.5%,96.3% and 83.7% respectively.When the temperature dropped to 4.5℃,NH3-N and TN removal efficiency decreased obviously,but COD removal efficiency were less affected.(3) When COD-sludge load was about 0.30 kgCOD/(kgMLSS·d),air to water ratio was 30:1,the aerobic sludge settling performance was good,SVI value was about 110.Effluent COD, NH3-N and TN concentrations were 33.3mg/L,1.8mg/L and 5.9mg/L respectively, the average removal rates were 92.5%, 95.5% and 83.7% respectively,and the Effluent concentration was met to GB18918-2002 grade A standards. The average effluent turbidity was 3.4NTU.When COD-sludge load increased to above 0.49 kgCOD/(kgMLSS·d),the phenomenon of sludge bulking occurred,SVI value was increased to 363 from 68.Sludge concentration in settling zone was very low and some sludge was washed out.The result showed that COD-sludge load of 0.30 kgCOD/(kgMLSS·d) was conducive to the stable performance of the system.更多还原