METHOD TO DEVELOP DEPOSIT WITH FORCED PRODUCT OFFTAKE AND DEVICE FOR ITS REALISATION Russian patent published in 2012 - IPC E21B43/12 

FIELD: oil and gas industry.

SUBSTANCE: method includes production from a bed with a water-oil mixture in a forced mode, separation of the product into oil and water, and pumping of the released water into the bed for water intake. According to the invention, an overlying bed is opened in the well for water intake, a device is lowered into the well in the form of a lower pump and an upper pump, the inlet device of which is made as a pipe between a casing pipe and a pipe string, providing for total speed of flow during water and oil offtake that is lower than the speed of oil floating in water to separate the product in the well into oil and water. At the same time the released water is pumped with the lower pump into the bed for water intake. Pumps are selected with efficiency corresponding to watering of the bed produce, and total efficiency providing for forced offtake of the product with water and oil mixture. The device comprises pumps with drives made as capable of their serial arrangement on the pipe string in the well and having inlet and outlet devices, and a packer capable of arrangement between beds in the well, one of which is with a water-oil mixture, and the other one is intended for water intake. The inlet device of the upper pump is made as a cylindrical reservoir with an inlet side hole communicated with a bed holding a water-oil mixture, and the outlet device of this pump is made as a valve unit that lets oil through into a pipe string. The outlet device of the lower pump is made in the form of a channel with an injection valve to inject water into a bed intended for water intake, and the inlet device - in the form of a channel with a suction valve for pumping of settled water into the pump. According to the invention, the reservoir is made in the form of a pipe arranged between a casing pipe and a pipe string with the area of the inner circular section that provides for total speed of flow during water offtake with a lower pump and oil with an upper pump, which is lower than the speed of oil floating in water during intensive offtake in the reservoir. The side hole of the reservoir is arranged below the foot of the bed with water-oil mixture and the inlet of the upper pump by at least 1 m. At the same time above the upper bed designed to intake water, between the casing string and the reservoir, which is made as open at the bottom, there is an additional packet installed, and a channel of the outlet device of the lower pump is communicated with an internal packer space of the well, besides, the side hole of the reservoir is arranged above the inlet device of the lower pump at least by 1 m and below the dynamic level of the water and oil contact.

EFFECT: higher oil recovery of producing formations due to lower watering of the products, limitation of water offtake, higher gradient of pressure in borehole environment of the bed.

2 cl