Predicting the Effect of Well Trajectory and Production Rates on Concurrent Oil and Gas Recovery from Thin Oil Rims

Abstract

Thin oil rim reservoirs are those with less than a 100 ft. of oil thickness underlain and overlain by an aquifer and gas cap respectively. Irrespective of the sizes of the aquifer or gas cap, oil rims productivity is usually low due to excessive coning of water and gas. Production optimizations are usually carried out before recovery schemes are initiated. One of such is a concurrent oil and gas production which is used in comparison with sequential production in this study in conjunction with production rates and well geometry to ascertain the extent of recovery and to improve the overall field development plan. Production of gas is slightly restricted to meet gas demands and also to prevent an adverse effect on oil production. A case study of an oil rim from the Niger delta was studied by running reservoir simulation using Eclipse software to check the effect of production schemes, well type and production rates on oil recovery. From the studies, concurrent production using a horizontal well and a production rate of 1000 stb/day is desired for an appreciable incremental oil recovery Further studies on limiting oil rim movements and thusly increasing oil recovery can be done by initiating secondary and enhanced oil recovery schemes.