| In light oil water injection blocks of Liaohe oil field, 65.95 % of recoverable reserve has been produced, and composite water cut is 78.35%. In major producing blocks, 85.0 % of recoverable reserve has been produced, and its composite water cut is 85.56 %. Xinglongtai reservoir of Liaohe oil field, which is a more completed water injection reservoir, has produced 84.29 % of recoverable reserves, and its composite water cut is 92.1 %. This reservoir has entered a stage of high water cut and high recovery percent of reserves("two-high stage"). Vertically, most oil formations were water flooded; and laterally, the residual oil was sporadicly distributed. Oil and water distribution is complicated in this reservoir, and the urgent problem to be solved is how to improve the development efficiency and ultimate recovery factor of high water cut oil field by changing injection agent. Molecular deposition film drive is a new nanometer film drive technology. The mechanism of nanometer film drive is different from traditional chemical drive (polymer drive, surfactant drive, alkaline drive and combined drive, etc.). It makes use of water solution as transmission media. The molecules in film agent interact and form into film-forming force by static electricity. The effective molecules of film agent deposit on the rock surface of electro negativity, and form a super thin film of nanometer level, thus changing the characteristics of reservoir surface and its interaction with crude oil. Therefore, when injected fluid is flushing pores, the crude oil is prone to move and replaced out by displacement agent, and reach the purpose of improving recovery factor.In 1998, Xinglongtai oil production plant conducted a Molecular film drive field test in well group Xing 53 in block Xing 42 which was a highly heterogeneous reservoir and in the "two-high stage". In this test, part of the observation wells had obviously increased daily oil production. Considering the Molecular film drive has succeeded to certain extent in well group 53 in 1998, it was decided to extend Molecular film drive in block Xing 212 in 1999. By the end of December 2000, oil increment in the whole block was 3235.6 t, cumulative gas increment was 32.5 + 104 m3. We can see that this technology is effective.In order to further testify the feasibility of Molecular film drive technology and to obtain experience for extensive spreading of this technology, we selected block Xing 209 from Xinglongtai oil field to further enlarge film drive test and to complete the matching technology of film drive and to provide reliable technical support and field experience for improving development result and recovery factor in "two-high" oil field and to provide basis for future study and spreading of molecule film drive technology. The unitized molecular film drive matching technology has been formed, including study of geologic characteristic, oil reservoir engineering. Mechanism of membrane drive, and optimization of injection parameters, and plan for field test designing, implementing, tracing and adjusting.Through comparison of displacement efficiency, it is determined that constant injection mode has an advantage of slug mode. The density of films agent injection between 300mg/L-500mg/L isfavorable for field test. Through analysis of affecting element of membrane drive , it is derived that films agent is compatible with salt water, and the oil displacement result of membrane drive with different water salinity is almost the same ,but the level of incremental oil production will become relatively small when the films agent drive system is solved by distilled water. The higher of residual displacement result, the more favorable of membrane drive displacement result. The study of mechanism of membrane drive shows that oil displacement by membrane agent on the one hand , depends on the super thin nanometer membrane deposited on rock surface due to electrostatic interact thus changing the relation between oil and rock surface ; on the other hand , depends on changing of wet...
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