METHOD OF DEVELOPMENT OF FORMATION WITH DIFFICULT TO RECOVER OIL RESERVES Russian patent published in 2003 - IPC

FIELD: oil producing industry; applicable in development of formations with oil reserves difficult to recover, with use of vacuum-wave stimulation. SUBSTANCE: method includes well washing; filling of well producing formation interval with fluid for treatment of bottomhole; allowing to stand for process completion; vacuum-wave stimulation of formation with simultaneous pumping-out of reaction products. At initial period of vacuum-wave stimulation, reduced level of fluid column in well is compensated with fluid for treatment of bottomhole zone supplied to well through annular space. In this case, bottomhole pressure is maintained at level of formation pressure. Then, supply of fluid to annular space for treatment of bottomhole zone is discontinued. Supplied to annular space through wellhead is withdrawn formation product. After increase of well production rate, vacuum-wave stimulation is discontinued and formation fluid is withdrawn. In this case, maximum volume of vacuum cavity in vacuum-wave stimulation is selected with consideration of technical potentialities of pumping unit and safety margin of sucker-rod strings. EFFECT: higher efficiency of formation stimulation due to maintenance of bottomhole pressure at level of formation pressure in process of vacuum-wave stimulation. 2 cl, 1 dwg, 1 ex