Research On EOR By Polymer Flooding In The East Of Nansi Area Of Sanan Oilfiled

The paper carried out the researches on fine geologic dissection and sedimentary units identification, optimized the polymer flooding method of EOR in the Eastern Nansi Area, and studied in detail in the well-collocation and exploration of the polymer flooding, based on the theory of fluvial-deltaic depositing pattern, and aiming at the problems of the relatively poor growth, the difficulty in the polymer flooding exploration, and the uncertain effect of the exploration of the oil layers of group PI in the eastern of Nansi area in Sanan oilfield in Daqing.The oil layers of group PI in the east of Nansi area mainly consist of deltaic distributary channel sands, and have the characteristic of counter-gyration deltaic deposit. The author identified two groups of sandstone and twelve sedimentary units. In order to solve the problems of small effective thickness, low permeability and high watered-out degree of the oil layers, the author optimized the injection parameters, designed an exploration plan of 200m*200m five points area well net for PI1-4 oil layers and a special injection system for fault block region, and forcasted the effect of polymer flooding. For some strata that are unsuitable for polymer flooding, the author carried out the research on polymer flooding method of EOR, by carrying out sedimental situation research on wells that are hand to inject polymer, proposed measures of adding holes, pressing cracks, adjusting profiles et al to the wells where oil-layer are debeloped in PI5-7, oil-layer pollution are serious and with different characteristics, which improved the reservior exploration degree and the integral effect of polymer flooding exploratoin.