The Design And Optimization Of Pressure-Maintenance Technical Plan To Heavy Oil Reservoir With Water Sensitivity

Qiguzu Reservoir in Tai3 Area is an ordinary heavy oil reservoir with water sensitivity controlled by the fault. It's in the initial stage of development now, facing the problem of the decline of the well oil rate, the daily decrease of the formation energy and water-flooding damage to the formation, and so on.To maintain the pressure of these similar reservoirs, design both technical and economic optimal development plans, and provide the reference development thoughts and research methods for this type of reservoir, basing on a great deal of researched literatures, the article firstly builds the typical reservoir numerical simulation model according to the field geological conditions and experiment data, then makes the model conform to reality through history match. Secondly, on the base of this model, the article researches the remaining oil distribution rules and find where the remaining oil is and how to develop it. Thirdly, the article calculates oil recovery of the depletion development, analyses the impacting factors of the water flooding, designs the water flooding development plan and optimizes the parameters through the black oil model of numerical simulator. After getting the recommended water-flooding technical development plan, in order to investigate the feasibility of the gas injection plan, the article recombines the formation crude oil, builds the component model to research the effect of gas injection based on the indoor experiment and gas phase behavior match. Then the gas injection pattern, the engineering parameters, well pattern and well spacing of the nitrogen and hydrocarbon gas are researched and analysed. The optimal gas injection technical plan with the way of orthogonal experiment design method is got. Finally, all the recommended technical plans are economic evaluated, and the best plan is chosen according to the result of the technical and economic evaluation.Base on the typical field and numerical simulation method, the heavy oil reservoir with water sensitivity numerical model is built; the remaining oil distribution law is analysed; the water flooding and gas injection plans are designed and optimized; the development plans are economic evaluated; and the technical and economic index of the water flooding and gas injection plans for the heavy oil reservoir with water sensitivity are compared. The results show that the best development method is the hydrocarbon gas and water alternate injection, and this will give a strong instructing and reference meaning to the same type of reservoirs.