Impact of the well placement density of water flooding process control by injection of carbon dioxide

Abstract

Using a 3D-model of a gas condensate field, the influence of the density of the grid of injection wells on the regulation of the process of flooding of the field when injecting carbon dioxide into productive reservoirs on the boundary of the initial gas-water contact is investigated. According to the simulation results, it was found that the water production cumulative decreases with an increase in the density of the grid of injection wells. In the case of using 4 injection wells to inject carbon dioxide into productive reservoirs, the water production cumulative is 169,71 th. m3. With an increase in the density of the grid of injection wells to 16, the water production cumulative is reduced to 0,066 m3. This result is achieved due to a more complete coverage of the perimeter of gas content with carbon dioxide and the creation of a reliable artificial barrier between water and natural gas, due to which an effective blocking of the advancement of marginal waters into gas-saturated intervals of productive horizons is ensured. A decrease in the activity of the water drive system determines the stable operation of production wells for a long period of additional development of the reservoir. Based on the results of the calculations, the maximum value of the number of injection wells is 6,41 (6) wells. The predicted of natural gas reco­very factor for the given maximum value of the number of injection wells is 64,05 %, and for depletion development it is 51,72 %. The results of the studies carried out indicate the technological efficiency of injecting carbon dioxide into productive reservoirs on the boundary of the initial gas-water contact in order to reduce the activity of the water-pressure system and increase of natural gas recovery factor for the conditions of a particular field.

Keywords

• 3d-model of the field
• gas condensate reservoir
• water drive
• trapped gas
• injection of carbon dioxide