Abstract: In sandstone bottom-water reservoir, accompanying with oil production, nearly-vertical pressure gradient will be generated at the lower position of oil-bearing formation and results in the bottom water moving upward. The author developed a new method of "producing water and eliminating conning",to restrain bottom-water movement and increase oil recovery. Using reservoir simulation technique studied its applicable conditions, applicable range, opportune moment and economic risk, etc., in terms of its mechanism. Through the analysis of a certain block of Tarim basin, it is recognized this method is more adaptable to middle-late period sandstone bottom-water reservoir development, and it will obtain good economic benefit for improved increase of crude oil recovery. It has bright future to be widely applied.

Key words: recovery factor, bottom water drive, reservoir, numerical simulation, pressure gradient