Composite profile control method for middle-high permeability oil reservoirs

Abstract

The invention discloses a composite profile control method for middle-high permeability oil reservoirs and belongs to the technical field of profile control of oil reservoirs. The composite profile control method for the middle-high permeability oil reservoirs is characterized in that the method comprises the following steps that 1, tracer agent detecting is conducted on a target block, and the waterline advance speed is determined; 2, polymeric microspheres are injected into a water injection well; 3, formation water is injected into the water injection well; 4, oil wells are selected according to the waterline advance speed of oil wells in the target block; 5, biopolymer solutions are injected into the selected oil wells; and 6, the oil wells injected with the biopolymer solutions are started up for production after being shut down for 10 d-20 d, and the rest of oil wells conduct normal production. The composite profile control method for the middle-high permeability oil reservoirs has the advantages of being wide in oil reservoir application range, good in plugging and adjusting effect and long in profile control validity period; the used profile control agents are small in using amount, low in cost and high in high-temperature resistance, salt resistance and stratum adaptability; thus, the composite profile control method can be widely applied to the technical field of water shut-off and profile control of the middle-high permeability oil reservoirs.

Description

technical field [0001] The invention relates to oil reservoir profile control technology, in particular to a compound profile control method for medium and high permeability oil reservoirs. Background technique [0002] During the long-term waterflooding of medium-high permeability reservoirs, the large amount of scour during waterflooding will cause the clay and cement in the oil layer to expand, dissolve, and migrate particles, resulting in more and more heterogeneous formations and the formation of large pores. Due to the heterogeneity of the reservoir and the unfavorable oil-water mobility ratio, the injected water advances unevenly along the high-permeability layer, and eventually the injected water breaks through in advance, leading to water flooding of the high-permeability layer and premature water breakthrough of the production well, which not only reduces The water sweep efficiency and water flooding effect are reduced, and the energy consumption increases, the tre...

AI Technical Summary

Problems solved by technology

In order to improve the water injection development effect and improve the water absorption profile, the commonly used profile control method is to inject profile control and water shutoff agent into the water injection well. This technology has the following disadvantages: 1. It can not only block the flow channel of water in the oil layer, but also It can also block the oil flow channel; 2. The leakage of the profile control agent in the oil layer fractures is very serious. Due to the increase of the fluid loss, the effective amount of plugging the oil layer fractures is correspondingly reduced, thus affecting the plugging effect; 3. , The amount of profile control agent is large, and the depth of profile control is limited, generally only the near wellbore area of ​​the well can be blocked