Research On The Remaining Oil And Tapping Potential Methods For Polymer Flooding At The Late Development Period In Xing 12 Block Of Daqing Oil Field

The research of remaining oil distribution law and tapping potential is an important part in the development of oil and gas fields. It is also a powerful guarantee for the highly efficient oil recovery. With the widely application of polymer flooding in Daqing oilfield, there is more and more attention on macro direction adjustment in the whole process of tracking adjustment with the oil development. However, it is not deep enough to describe the remaining oil which has been polymer flooded in quantification. In order to further develop the techonology of tapping potential for polymer flooding, this thesis chose Xing 12 block of Daqing oil field to study the remaining oid and tapping potential methods for polymer flooding at the late development period. The following methods are used as research method: numerical simulation, injection production well logging data, sealed coring data, and fine geologic research results. With the aboved results to analysis of polymer flooding development later in the plane and vertical macro remaining oil distribution and sedimentary unit internal residual oil distribution law. It is proposed different types of remaining oil potential in technology and method in the thesis, which has important significance on how to further improve the ultimate recovery of polymer flooding. These methods are also useful to slow down the speed of water picking up in the late polymer flooding, and which are helpful to increase stage of oil production and the sustainable development of oilfield. At the same time, it will indicate the approach and direction for other polymer injection block, and provide technical support and experience. According to the study, the research results are sumerized as follow:Firstly, in the stage of water flooding and polymer flooding stage history matching, the moisture content of fitting the absolute error of 0.12% and 0.25% respectively, recovery degree absolute error of 0.18% and 0.08% respectively.Secondly, the characteristics of remaining oil distribution after polymer injection has been studid, the mainstream line average residual oil saturation is 0.2947, the shunt online 0.3146 average residual oil saturation. For polymer injection residual oil is mainly distributed in polymer flooding well pattern distribution line, cycle polymer injection way of remaining shunt line of remaining oil can be used.Thirdly, it is forecasted the development effect with injection-production method of combination cyclosymmetric function and linear cycle in 4 months, 6 months, 8 months and 10 months. The results show that the combination of injection-production method cyclosymmetric function and linear periodic injection-production cycle in six months will get the best economic benefit. The two aboved types of development stage of polymer flooding recovery degree of 11.20% and 11.49% respectively, the net income of 17.074 million yuan and 12.66 million yuan respectively, so the combined earnings cyclosymmetric function is better.Last, after the combination rotation for six months, the polymer concentration of 1800 mg/L development effect is the best, the stage of polymer flooding recovery degree is 11.31% at the moment.