Porous Carbonate Rock With High Permeability Layer Improves Water Injection Development Efficiency

The Ahdeb oilfield is a typical porous carbonate reservoir.The Kh2 layer is the main oil layer of the oilfield.It is developed by water injection with horizontal wells.Affected by the high permeability zone and fracture zone,the water cut in the oilfield is rising rapidly.The contradiction of high water content is becoming increasingly apparent.In order to deeply explore the factors that affect water injection development,establish a water injection development diagnosis model,combine geological data and production data,and classify and study the production wells affected by high permeability zones,fractures and bottom water to obtain a plate for diagnosing water flooding.Carry out the numerical simulation analysis of the horizontal well pattern with two injections and one production,study the influence of high permeability layer,fracture development degree,injection and production well position and injection and production ratio on water cut rule,establish the numerical simulation model of AD-1 area,The analysis of the water drive law of the wells showed that the flow channel of the high permeability layer is the main reason for the rapid rise of water content.The wells produced in the fracture area are produced by the injection of water and natural bottom water at the bottom of the fracture.Establish a typical well group to study the development measures for adjusting the scale of injection-production,periodic injection and plugging of high-efficiency injection.The results show that the enhanced injection-production method is adopted for AD1-7-2H,and it is predicted that the water content will not change much,the oil will be doubled,and the pressure will remain relatively stable.AD1-9-2H is adopted to reduce the injection-production ratio,and it is predicted that the water cut will decrease by 2%and the daily oil production will increase by 10m3.The periodic water injection mine experiment has achieved good application in the crack control area of AD-2 area.It is obvious to block high permeability layers in water injection wells.At the same time,block the second and third layers of AD1-6-2H and AD1-8-2H.AD1-7-2H has the best precipitation effect.The research results of this paper further perfect the water injection development research of porous carbonate rock with high permeability layer,which is of great significance to guide the efficient water injection development of porous carbonate reservoir.