MBR-BAF处理采油废水研究

【作者】 田慧颖；

【导师】 杨凤林；

【作者基本信息】 大连理工大学 ， 环境工程， 2004， 硕士

【摘要】 辽河油田作为我国的第三大油田，原油产量为1500万吨／年，在我国的国民经济和能源战略上具有举足轻重的地位。但是，随着原油开采技术的发展和原油产量的提高，相应产生的废水水量也在逐年增加，不达标废水的任意排放对外界环境造成了严重的污染问题。 本课题的主要目的在于设计一套适合采油废水特点的污水处理工艺，实现采油废水的达标排放。研究以辽河油田兴一联合站的采油废水为试验对象，通过为期6个月的实验室小试和将近3个月的现场中试（处理规模为1m³／h），验证了“气浮（加药）—MBR—BAF—排放”工艺流程在采油废水处理中的有效性和适用性。 在实验室小试阶段，考察了污泥的培养驯化阶段（间歇进水）污泥的性状，并以反应器出水中的污染物指标合格作为污泥驯化成功的标志；还考察了试验稳定运行阶段（连续进水），不同的HRT（水力停留时间）下，各种污染物的去除效果和膜的连续出水情况。试验结果表明，HRT=10h是膜生物反应器的最佳运行参数，在原水水质COD-400mg／L，BOD-80～100mg／L，SS-100mg／L，油-50mg／L的条件下，COD去除率可达到80％，BOD、SS和石油类物质的去除率均在90％以上，出水可以直接排放。同时，该水力停留时间能够保证膜在较长时间内连续出水，反应器运行稳定。 在小试基础上，于现场进行了处理规模为1m³／h的中试研究，首先进行污泥的培养驯化，之后在HRT=10h的参数下运行，试验出水仍然保持较高的污染物去除率，系统出水COD基本保持在90mg／L左右，BOD为2～3mg／L，SS、NH₃-N和石油类等均在1mg／L以下，完全能够达到国家规定的污水排放标准。更多还原

【Abstract】 The amount of crude oil that is recovered in Liaohe Oil Field each year can reach 1.5 107 ton. However, with the development of the oil recovery technology and the exaltation of the crude oil yield, the amount of the accompanying wastewater (produced water) begin to increase year after year and the arbitrarily discharged wastewater has caused serious environmental problem.The main object of this paper is to design a set of rational technological process that is suitable for produced water to achieve environmentally acceptable disposal of this kind of water. On the basis of current produced water treatment methods, we took the technological flow - "air-floatation (adding chemical) - MBR - BAF -discharging" to treat produced water from Xingyilian (the name of an oil recovery site) and obtained satisfactory results.In laboratory experiment, we observed the properties of the sludge during cultivation (discontinuous influent mode) and took the concentration values of pollutants in the supernatant fluid which had been treated by microbes as the indication of domestic active sludge. And since the set of devices had began to run steadily (continuous influent mode), we reviewed the disposing effect of the pollutants and the state of the membrane. From the experiment, we concluded that when the COD of raw water was about 400 mg/L, BOD 80-100 mg/L, SS about 100 mg/L and oil content about 50 mg/L, the rate of COD removal could reach 80%, and removal of BOD, SS, oil content were all above 90%, effluent could be discharged to surfaces directly. And HRT = 10h was the best working parameter for the system, under which decent removal effect could be achieved and also the membrane kept fine state.On the basis of laboratory experiment, we carried on field pilot-plant-scale test (disposal quantity was 1 m3/h). After the sludge cultivation, the system was operated with the parameter of HRT =10h, achieving effluent with following characters -COD was about 90mg/L, BOD was about 2-3 mg/L, SS, NH3-N and oil content were all less than 1 mg/L. The quality of the system effluent could fully fit the national required discharged wastewater quality.更多还原