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Currently Daqing Oilfield has entered the high water stages of development, since 1995, has become a polymer flooding in Daqing Oilfield Oilfield high water cut period widely used EOR technologies. With the main reservoir of polymer flooding area expansion, increase reserves and production oilfield development faces a potential class main reservoir remaining reserves decreasing the grim situation, we must dig two categories polymer injection reservoir production potential in order to achieve a successor. Which is different from the main oil reservoir is characterized by longitudinal multi-layered, flat photogenic larger, serious heterogeneity, the greater difference in the nature of non-homogeneous reservoirs generally classified together, combined into a strata development, showed significant suited, seriously affected the development effect. To solve this problem, we must further subdivided reservoir type, reservoir type uniform criteria to determine a reasonable injector spacing, layer-based methods and combinations of injection parameters, to facilitate EOR oil field development and design stage fine. Thesis has been developed by two from three oil field tests fine geological findings and existing research results starting on the two categories reservoir sedimentary characteristics, reservoir heterogeneity, sand body connectivity between wells such a detailed manner research, find out the characteristics of the physical properties of reservoir distribution, reconstructed from a development perspective EOR oil type, dividing the specific criteria to adapt to two preliminary studies have identified three types of thin and poor reservoir reasonable injector spacing, layer-based combination methods and injection parameters. The results show that: From the Zone classification reservoir thickness and reserves distribution, a class of oil from north to south gradually worse, reserves decreased from Ⅰ A transition to Ⅰ B oil reservoir, to apricot South Zone evolved into sub-layers; two , three types of reservoir reasonable injector spacing respectively 150m-175m and 100m-125m has a higher degree of control; II oil combination should sandstone layers based group strata units combined to ensure the two segments spacer layer relatively stable, the same level segment reservoir geological conditions should be as close as possible to ensure the onrush coefficient is less than 3.0, so that 70% or more layers suitable for injection into the same kind of small molecular weight polymer, and not too long segment extraction wells in 40-60m more appropriate, up and down layer boundary is 6 ~ 8m. In addition, the paper also three types of oil from two layers of large differences exist between the physical properties, the pressure difference between large and multi-layer thin and poor geological conditions and issues such as starting, supporting the study identified three categories of oil returning to adapt two layers of polymer injection in High Quality partial pressure implantation, thin barrier fracturing and polymer flooding by injection and many other technology, thin and poor solves the problem of poor results injection layer, forming a more complete supporting the development of thin and poor layer technology for two categories reservoir EOR comprehensive application play a strong theoretical and technical support. Field test results show that two, three reservoirs polymer injection is feasible, cost-effective than the industry standard.
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