Method for improving recovery ratio of sealed small fault-block oil reservoir through alternate coupling injection and production of oil-water well

Abstract

The invention provides a method for improving the recovery ratio of a sealed small fault-block oil reservoir through alternate coupling injection and production of an oil-water well. The method for improving the recovery ratio of the sealed small fault-block oil reservoir through alternate coupling injection and production of the oil-water well comprises the following steps of 1, selecting a complicated fault-block oil reservoir subjected to the alternate coupling injection and production; 2, analyzing the development condition of the oil reservoir, and determining the oil-water well capable of being subjected to the alternate coupling injection and production; and 3, the determining the technical policy for implementing the alternate coupling injection and production. The method for improving the recovery ratio of the sealed small fault-block oil reservoir through alternate coupling injection and production of the oil-water well has the advantages that a novel method is provided for improving the development effect of the complicated fault-block oil reservoir and improving the recovery ratio of the oil reservoir; the popularization and application prospects are wide; and obvious economic and social benefits can be obtained.

Description

Technical field [0001] The invention relates to the field of development methods of complex fault block oil reservoirs and enhanced oil recovery, in particular to a method for improving the recovery of closed small fault block oil reservoirs by alternately coupled injection-production of oil and water wells. Background technique [0002] The geological characteristics of complex fault block reservoirs are small area, diverse plane geometry, closed, many small layers in the vertical direction, and strong heterogeneity. The characteristics of the reservoir have caused the contradiction between injection and production in development. That is, the oil well will be flooded quickly when water is injected into the water well, and the oil well will be insufficiently supplied when the injection is stopped. When the water injection is stable, the injected water flows along the main flow line, with a small spread range, and the fault angle , The remaining oil in the broken edge zone is dif...

AI Technical Summary

Problems solved by technology

The characteristics of its reservoirs cause the contradiction between injection and production in development, that is, when water is injected into the well, the oil well will be flooded rapidly; , The remaining oil in the broken side zone is difficult to develop, and the recovery degree is low

Current studies have shown that the main line of the oil-water well and the main layer have large pressure gradients due to small well spacing and differences in vertical physical properties, while faulty side zones and layers with poor physical properties are less productive due to small pressure gradients. There is still no effective means to solve this contradiction between injection and production, and to further greatly increase the sweeping degree of water flooding in complex fault-block reservoirs.

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