| The water-injection development is leading one of the current oil and gas explotation modes. In China,about 86.3% of the oil fields apply water- injection development. The water-injection development is the one of most important jobs in the production processes of the oil field explotation.It not only may effectively supplement and maintain reservoir pressure and oil field energy, but also improve the crude oil recovery ratio and guarantee oil field high and stable crude oil quatity. But at present the water-injection treatment technologies of the majority of oil fields have many urget and solved problems:manual operation, management inconvenience, the effluent water not reaching the standards of the water quality and high operating costing,and so on.In the view of the above existent questions,based on the amount of literature and references,and the analysis on related basic data, taking the elementary theory of ultrafiltration as the instruction, taking the scene deb- ugging, the experimental study and technology and economy comparison as the methods, taking the effluent water quality satisfying the A1 standard of the"Clastic rock oil deposit to pour water quality recommendation indexes and analysismethod" (SY/T5329-94) as the purpose, this paper conducts the experimental study of using the ultrafiltration(UF) technology treating rins- ing water-injection for low permeability oil field in the black 98 water- injection station affiliated the Jilin oil field. This study spends four months on the experimental study in the scene, and is divided into three stages to carry on, that is to say, the stage of the UF debugging and trying to operate, the stage of process operation analysis stage, the stage of removing disolved oxygen and the corrosion and scale inhibitation. In this experiment the used UF membrane is the hollow UF membrane,and its material is the new PVC alloy. Compared with the other materials, this membrane has the character- istics of it much more bearing pollution, the pH value scope being 2～13, it removing the fungus well, it operating in low pressure,it producing more efflucent water, and its design applying the intercrossing current, and so on.In the stage of the UF debugging and trying to operation, the apparatus realizes the manual control and the automatic control for the operating condition through the PLC system. This PLC system decreases the work load, and enhances the operation reliability, and prevents the membrane damage by the misoperation, carries on the wash by the different ways or the way of these uniting ways at random,and lengthen the membrane life, and so on. When the UF apparatus is debugging, this study analyzes the reasons for membrane flux reducing gradually under the manual control pattern by the theory, for the membrane undertaking the instantaneous bigger membrane pressuure under the automatic pattern, and for analyzing the pressure turnover of influent and effluent water, and proposes corresponding solutions.In the stage of process operation analysis, this paper carries on the study from the two aspects being the choice of the best process parameters and the comparison of the water quality of the two process. Based on the success in the debugging and trying to operate, and under the condition of ensuring the membrane modules have the reasonable energy consumption, the higher membrane flux, the better effluent quality, the longer service life, this paper is in order to definites the best operation parameters. Through the data analysis, the paper definites the best operation parameters: the best influent pressure is 0.06MPa; The best wash way is way four,namely back air-water→backwash→bottomb ackwash→bottom air-water backwash→bottom backwash→back air-water backwash→front air-water frontwash; the best wash time is 60s,and wash time of six stages in the fourth way is equally 10s; the best wash cycle is 90min. Then, the paper studies that how the water temperature influences the membrane flux, and it discoveres when the temperature rises, the membrane flux increases nearly with the linear relations; the two empirical relationship is J=0.5108t+31.74; the relativity is R2=0.9714. Finally, the comparison and the analysis of the effluent quality of the UF process and the fine filteration process at present is done. The results indicate: the UF process has good treatment performance effect under the condition of the best operation parameters, the effluent water indexes that include pH, SS, total Fe, bacteria satisfying A1 standard, but the following measurements are needed in order to remove the dissolved oxygen; the fine filteration process has poor processing effect, the water indexes which include pH, SS, DO, bacteria do not satisfy A1 standard, but total Fe index satisfies the standard.In the stage of removing disolved oxygen and corrosion and scale inhabitation, in order to make DO in the effluent water of the UF procsss satisfy the water-injection demand, the removing oxygen experiment are done,the used deoxidizer being the sodium sulfite in the water-injection station. Sodium sulfite represent the inorganic reducing agent.It has the characteristics of fast oxygen removal speed, high oxygen removal rate,still having oxygen removal ability in low temperature,stable performance, low investment, security, simple operation. The results indicate:when the sugge- stedly added sodium sulfite density is 17.5mg/L, the DO value in the water is lower than its standard value 0.5mg/L, and this desity is 17% smaller than the density of the fine filteration; before the deoxidizer is added in the UF effluent water, there is no need to adjust the acid or andalkali. For avoiding oil field equipment's corrosion and thescaling,and also in order to solve the higher corrosion and scale inhabitation desity(78mg/L)which is added in the present fine filtration process's effluent water in the black 98 water- injection station, the corrosion and scale inhabitation experiment about the UF effluent water is done, and the used corrosion and scale inhibitor is combination,and its type is IMC-50-H.The results indicate: the best corros- ion and scale inhabitation desity is 30mg/L, now corrosion rate being lower than the standard value 0.076mm/a, and this desity is 61.5% smaller than the density of the fine filteration.According to the economic level of our country and the current situation of the oil field development,UF process is one of the new processes which have competitive ability and are sutiable to our national conditions. This UF process has the very good economic efficiency, environmental benefit and the social efficiency, and will be able to have the broad promoted application in the future. This study might provide the reliable technical support for the UF development in the future.
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