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According to statistics, currently the world's remaining oil resources of approximately 100,000 barrels, 70% of which is heavy oil, and a huge amount of resources determines the heavy oil is bound to be the major source of energy of the 21st century. Heavy oil development and production of steam injection thermal recovery steam stimulation. As the proportion of heavy oil development and production growing sewage problems facing more and more serious. Heavy oil sewage is complex because of its water quality ingredients, poor biodegradability, high salinity, oil-water density difference processing difficulty is relatively large, the processing of heavy oil sewage problem is an urgent need to solve the problem faced by the various oilfields. Heavy Oil Sewage treatment methods include physical treatment, chemical treatment, physical chemical treatment, and biochemical processing method. Physical, chemical processing is not complete, the high cost of the biochemical approach has low cost, high effect, no secondary pollution by sewage treatment the attention of researchers and workers. In this thesis, the use of the national \- membrane bioreactor (MBR) process to replace the existing biological contact oxidation - settlement - dual media filtration process. Hydrolysis acidification reaction of heavy oil sewage experiment found that the hydraulic retention time greater than 16h, pool acid hydrolysis stable operation at 15 ~ 35 ℃ can be little effect of temperature on the hydrolysis acidification effects. Hydrolysis acidification effluent COD Cr values ??between 220 ~ 240mg / L, the removal rate of between 25% to 33%, the oil content of the effluent of hydrolysis acidification of about 2.00 ~ 5.00mg / L, The removal rate is higher than 75%. Hydrolysis acidification influent BOD5 between 54 ~ 75mg / L, BOD5/COD Cr 0.17 to 0.23, poor biodegradability; the effluent BOD5 between 95 ~ 112mg / L, BOD5 / COD Cr between 0.45 to 0.49. Hydrolysis acidification improve sewage biodegradability plays an important role. Due to the effluent biodegradability improve, will have to help shorten the follow-up process of hydraulic retention time, and to follow-up the organic matter in sewage treatment processing biodegradable method more thorough. Domestication, with the of hydrolysis acidification of water on the activated sludge pool MBR easy to observe due to aerobic activated sludge protozoa can take advantage of protozoa detection performance of activated sludge. The results showed that rich bacteria in aerobic activated sludge, and domesticated the early paramecium, bean-shaped insect, turned to other insects, poor water transparency the general COD Cr gt; 150mg / L,; amoeba, dastardly pipe leaf miners when paramecium disappear, reduce the number of bean-shaped insect, turned to insects, improved water quality, better transparency, general COD Cr lt; 150mg / L amoeba disappear, reducing the number of the dastardly tube leaf miners, better water transparency; When the bell insects, rotifers, Euplotes Dun fiber and other insects when General the COD Cr lt; 120mg / L; When Case insects when the transparency of the water is poor, general water the COD Cr lt; 120 mg / L, the sludge load is low, the hydraulic retention time is too long. When the sludge acclimation, the supernatant effluent COD Cr between 117 ~ 130mg / L, the removal rate of between 40% to 47%, the oil content of the effluent is less than 1.00mg / L removal rate is higher than 90%, less than 10mg / L, the effluent BOD5 start MBR membrane. Hydrolysis acidification-MBR system stable operation the effluent COD Cr between 69 ~ 90mg / L, the system on the removal efficiency of COD Cr 70%; MBR membrane water oil content of 0.09 ~ 0.30mg / L between the removal rate of the entire system for crude oil is more than 99%; of the MBR film effluent suspended solids content of less than 1.0 mg / L, suspended solids removal rate at 95%. Hydrolysis acidification-MBR system water compared with the existing technology in dual media water COD Cr reduced by 32%, the oil content of 93%, a 88% reduction in suspended solids.
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