Abstract
It is complex and obviously different for the production characteristics of CO2 water- alternating-gas flooding in tight reservoir and influenced by many factors. Therefore, the production prediction is a key matter of efficient development of CO2 water- alternating-gas to be solved in tight reservoirs. In order to solve this problem, in this paper, the production characteristics of CO2 water- alternating-gas flooding production well are analyzed and classified in tight oil reservoir of Block A as an example. On this basis, geological, fracturing operation and development factors are considered and the sensitivity of the influencing factors was carried out. The grey relation analysis(GRA) was used to screen the main influencing factors of poduction and establish the poduction evaluation model to realize the rapid prediction production. The results show that the wells of CO2 water- alternating-gas flooding in tight reservoirs can be divided into four types. The production is affected by permeability, reservoir thickness, amount of sand entering the ground, amount of liquid entering the ground, gas/water ratio, injection rate and injection pressure, and the main influencing factors of production are amount of sand entering the ground, reservoir thickness and amount of liquid entering the ground. The production of oil can be predicted quickly based on the relation between production and comprehensive evaluation factor of production. The average relative error between the predicted results and the actual predicted production is 8%, which proves the reliability and accuracy of this method.
Fine Geological Modeling of the Tight Oil Reservoir
