RU2351753C1 - Method of operating two-head well - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention refers to development of hydrocarbon deposits with two-head horizontal wells and can be implemented for extraction of high viscous oil and bitumen. The essence of the invention is like follows: the method consists in exposing payout reservoir with a horizontal borehole and in casing it with a production string preliminary equipped with a filter in the interval of the exposed payout reservoir, then in equipping the heads, in installing a blind packer through one head in the interval of the payout reservoir of the well corresponding to water flooded boundary, in operating the well via the second head with implementation of a pump. According to the invention the blind packer is installed beyond the water-flooded boundary from the side of the pump and the water flooded section of the exposed payout reservoir is cut off. Further the pass-through packer is installed on the water-flooded boundary. After installation of the packers the pump is shut down, and isolating compound is pumped into the water flooded section of the exposed payout reservoir. When isolating compound has hardened or coagulated, the pump is turned on.

EFFECT: simplification of packer assembly in well, also facilitating, by means of packer, isolation of water flooded section of exposed payout reservoir of two-head well without lifting intra-well equipment.

1 dwg

Description

The invention relates to the field of development of hydrocarbon deposits by double-well horizontal wells and can be used for the simultaneous production of high-viscosity oils and bitumen and repair double-well wells.

A known method of developing deposits of viscous oils and bitumen (RF patent for the invention No. 2246001, IPC 8 ЕВВ 43/24; published in Bulletin No. 5 of 02/10/2005), including drilling a two-well horizontal well, fixing it with a production string, dragged from one wellhead along its wellbore to another wellhead together with packers for installing the latter in the roof of a productive formation, raising and supplying oil to a flow line at one of the wellheads, and the wellhead sections of the production string are interconnected by a ground section in the form of arcs a similar pipeline with an identical inner diameter to form a closed channel, the above-ground portion of which is fixed on the support frame of the drive unit, after which an additional string is installed in the production string, which acts as a tubing in the underground part and has perforation channels for communication with the productive layer, in the cavity of the additional column at equidistant distances from each other establish a system of cylindrical elements interconnected by means of power rods with the formation of a closed traction system, while sections of the underground part of the tubing from the wellhead to the boundaries of the perforation section of the production string together with the aforementioned cylindrical elements form piston pump pairs, and during operation, the system of cylindrical elements is forcedly moved using a drive unit with continuous successive displacement of oil from the tubing by means of the piston pump pairs mentioned above.

The disadvantage of this method is the metal consumption of the structure on the surface, associated with the presence of a land section in the form of an arcuate pipeline, which is fixed on the supporting frame of the drive unit, and this leads to an increase in the cost of the structure as a whole.

The closest in technical essence and the achieved result to the proposed one is “The method of construction and method of operating a horizontal well” (RF patent No. 2159317, IPC ЕВВ 7/04, ЕВВ 43/20, published in bulletin No. 32 of 11/20/2000 ), including drilling and fastening of the vertical direction, drilling and fastening of an inclined directional shaft and a horizontal section of the wellbore, characterized in that a second vertical direction is drilled and fastened at the design distance from the wellbore, and when drilling under the conductor, a set of zenith angle in the direction of the first mouth, after reaching the horizontal, the trunk is cased with a technical column whose diameter is equal to or greater than the diameter of the technical column, lowered from the first mouth, drill the shoe of the technical column with the outlet and extension of the barrel from under the shoe to the length of the bit with a connecting device and a layout including a telemetry system and a docking device, and lower this layout, not reaching the bottom face at a distance of not less than the length of the bit with a docking device, and provide pointing a horizontal section of the trunk, which is drilled from the first wellhead with a telemetry system providing control of the trajectory of the trunk and pointing the bit with the connecting device to the connecting device, insert the bit with the connecting device into the connecting device, attach the casing of the production string to the drill pipe string on the first mouth , at the second mouth create a tensile force to the bottom of the production casing, which frees the casing from wave-like pressing walls of the well, and pulls it to the second mouth, mounted on the production tubing at least one in-casing packer interval corresponding to the contour planned waterflood.

The disadvantages of this method are:

firstly, the complexity of installing an annular packer in the well, since it is installed as part of the production string during the construction of a horizontal well;

secondly, it is impossible to isolate (colmatate) the flooded area of the uncovered reservoir using a casing packer.

An object of the invention is to simplify the installation of the packer in the well, as well as the possibility of using the packer to conduct isolation (mudding) of the flooded section of the uncovered productive formation of the double-well well.

The technical problem is solved by the proposed method of operating a two-well well, including opening a reservoir with a horizontal wellbore and attaching it with a casing string pre-equipped with a filter in the interval of the opened reservoir, equipment of the mouths, installation of a blind packer through one well in the interval of the reservoir, corresponding to the waterflood circuit, well operation through the second wellhead using a pump.

What is new is that a blank packer is installed behind the water supply circuit on the pump side with the waterlogged section of the exposed reservoir turned off, then a feed packer is installed on the waterlogged circuit, after the packers are installed, the pump is stopped, the insulating composition is pumped into the watered section of the opened reservoir, and after hardening or coagulation of the insulating composition of the pump include.

The proposed method is as follows.

First, the productive formation 1 is opened by a horizontal shaft 2, which is then fixed by the casing production string 3. Next, the mouths 4 and 5 are respectively equipped with a two-well well, and before the production string 3 is lowered into the horizontal well 2, it is pre-equipped with a filter 6, which is placed in the interval of the opened production reservoir 1.

Then through the second mouth, that is, mouth 5, lower the tubing string 7 with the pump 8 at the end. The pump 8 may be of any known design, for example, electric centrifugal (ESP), designed for pumping highly viscous oil or bitumen.

Next, at the second wellhead 5 of the double-well well, the tubing string 7 is sealed with a sealing device 9 and the double-well well is started to operate. In the process of operating a two-well well, the opened producing formation 1 begins to be watered, as evidenced by an increase in the water content of the products produced from the well (high viscosity oil or bitumen).

In order to reduce the water cut of the produced products into the double-well well from the first wellhead, i.e., from wellhead 4, on the tubing string or flexible pipe (not shown), the deaf packer 10 of any known design (for example, mechanical, with the possibility of subsequent reinstallation in production casing 3) is lowered .

The deaf packer 10 is installed in the production casing 3 behind the watering circuit (not shown) on the pump 8 side with the water-cut section 11 of the uncovered reservoir 1 turned off, then the deaf packer 10 is planted in the production casing 3, and the tubing string or flexible pipe is removed to the surface .

Further, in order to isolate (clog) the irrigated section 11 of the opened producing formation 1 with a horizontal wellbore 3 into the double-wellbore from the first wellhead, that is, from the wellhead 4, the tubing string 12 is lowered, for example, with a through packer 13 at the end.

Next, the passage packer 13 is planted in the production casing 3, on the irrigated area 11 of the opened reservoir 1.

Stop the pump 8. Then, from the first mouth 4, along the tubing string 12 through the section 14 of the horizontal shaft 2 of the production string 3 and part of the filter 6 of the production string 3, an insulating composition, for example, a water-swelling polymer, is pumped into the flooded section 11 of the opened reservoir 1. Then, the passage is unpacked the packer 13 in the production casing 3 and remove the tubing string 12 with the feedthrough packer 13 from the side of the second mouth 4, after which the second mouth 4 is sealed on the surface.

After the hardening or coagulation of the insulating composition, the pump 8 is turned on.

Thus, the operation of a double-well well (production of highly viscous oil or bitumen to the surface) is carried out continuously through the second wellhead 5 of the double-well well, including during repair of the double-well well from the side of the first wellhead 4.

The proposed method simplifies the installation of the packer in the well, since the packer is deaf and installed directly in the production casing with the possibility of isolation (colmatation) of the flooded section of the uncovered productive formation from the first mouth of a two-well well, and operation (production of high-viscosity oil or bitumen to the surface) is carried out without stopping during repair (isolation) through the second mouth of a two-well well, which allows efficient operation of a two-well well.

Claims (1)

A method of operating a two-well well, including opening a producing formation with a horizontal wellbore and securing it with a casing production string, previously equipped with a filter in the interval of the opened producing formation, installing wellheads, installing a blind packer through one wellhead in the interval of the producing well formation corresponding to the flooding circuit, operating the well through the second wellhead using a pump, characterized in that the blank packer is installed behind the water circuit on the pump side with By shutting off the flooded section of the opened reservoir, the feed packer is installed on the flooding circuit, after the packers are installed, the pump is stopped, the insulating composition is pumped into the flooded section of the opened reservoir, and after the hardening or coagulation of the insulating composition, the pump is turned on.