Development Strategy and Optimization of Strong Bottom Water Offshore Heavy Oil Reservoirs

The development of Bohai bottom water heavy oil reservoirs is facing the challenge of poor reserve quality. Taking C oilfield as an example, its longitudinal span is 700 m, crude oil viscosity is 30–452 mPa · s, and there is a multi oil-water system. The traditional development model is prone to problems such as bottom water breakthrough and soaring water content, resulting in poor economic viability of marginal oil fields. Innovatively adopting a combination of flat rolling well layout and vertical interlayer development mode, early high displacement liquid extraction maintains high yield, and system load is maintained through lateral drilling of old wells. Four key technologies are proposed for the high water cut period: intelligent production control, wellbore pressure cone wheel mode, strong bottom water injection, and mechanical water control for horizontal wells. On site application shows that 54 wells increase oil production by 20000 cubic meters per year, 3 lateral drilling wells increase oil production by 35 cubic meters per day, 56 wells increase mechanical water control by 15000 cubic meters per year, and 2 injection wells increase oil production by 42 cubic meters per day in the initial stage. This technology system effectively improves the utilization rate of reserves and provides a demonstration for the development of "edge low thickness" oil reservoirs.