Study On Factors Affecting Oil Recovery Of Bottom Water Reservoir

Horizontal or anticline structures with oil underlain by bottom water and dipping reservoirs with attic oil and side water are the two most typical geological scenarios to form bottom-water and edge-water reserviors. During the process of development and prodution of the reservoirs, the bottom and edge water would provide natural energy for the displacemet of the crude oil, however, the natural bottom and edge water always tends to form a water cone or water tongue under the bottom of the well hole, because the pressure drops as the shape of the funnel nearby the wellbore, which makes the water breakthrough earlily at the well, the water cut rise fast, and the recovery degree decrease, result in a poor reservoir development effect. Besides, the reservoir physical property, fluid property and human development measures would also have significant impact on the reservoir development effect.In this paper, based on basic geologic and development characteristics of bottom and edge water reservoir, on the basis of Qinhuangdao32-6oil field data, with the reservoir engineering theory, seepage flow mechanics theory, reservoir numerical simulation method and mathematical statistics analysis, The research to influential factors of bottom and edge water reservoir recovery efficiency has been carried out. This paper has obtained the following results:(1) Based on the typical geological and developmental characterristics of th edge and bottom water reservoirs, and the percolation mechanism of bottom and edge water reservoir, this paper has got a rough claasification of this kind of reservoir and summarized the main development effect influential factors from the three aspects, the aspects of which would be reservoir physical and fluid property and development measures;(2) With the of method numerical simulation, this paper has built the single well numerical simulation model of the edge and bottom water reserviors, and then has carried out the relationship between the every influential factors and the oil recovery.;(3) The orthogonal experiment designing method has been carried out to study the rules and relationship between the oil recovery and the multi-ply influential factors,at last, the weighting index and infulential orders of the factors have been got;(4) With the matlab software, a multivariate non-linear regression has been carried out, and finally, the quantitative characterization models of the oil recovery with infulential factors of bottom and edge water reservoir have been got.