RU2499133C2 - Electrically drive pump unit for oil extraction and fluid injection in bed - Google Patents

Abstract

FIELD: oil-and-gas industry.

SUBSTANCE: proposed unit comprises electrically driven rotary pump with extra section arranged under downhole motor at common shaft and having channel in the case for bottom bed fluid escape into well behind-the-packer space, hydraulic protection, intake pipe for bleeding of bottom bed fluid with packer arranged between top and bottom beds. In compliance with this invention, inlet pipe is arranged between fluid bleed pipe and extra pump section. Said inlet pipe terminates in flow plunger and had baffle above which channel for intake of broken associated water is located to feed said water to pump extra section intake. Channel communicated with extra channel outlet via flat tube is arranged under said baffle. Intake pipe has the cylinder to make with said plunger a pair of friction and terminating in separation funnel. Note here that said separation funnel is located above the channel receiving broken water in inlet pipe.

EFFECT: higher efficiency.

4 dwg

Description

The present invention relates to the oil industry and can be used for simultaneous and separate oil production and injection of the associated produced water separated in the wellbore into the lower aquifer, as well as for the production of flooded oil from the side wellbore and pumping the separated water into the absorbing horizon through main wellbore.

For simultaneous separate oil production and water injection (ORDiZ), a screw pump installation / 1 / is known, consisting of two successive screw pairs, the upper of which pumps the oil phase to the surface along the tubing string, and the lower pumps the stratified formation water in the well into the under-packer zone into the underlying water-absorbing horizon. The installation has a boom drive and does not allow for significant oil production and water injection volumes.

A well-known sucker rod pumping unit for ORDiZ with a double-acting pump / 2 /, which is an articulated 2 plungers of different diameters, the lower of which with the help of valves pumps out formation water, and the upper with the help of other valves pumps out the oil phase. The disadvantages of the installation are the presence of two plunger pairs that increase friction in the underground equipment, as well as the relatively small total supply of the installation.

Closest to the proposed invention is an installation for simultaneous-separate operation of two layers / 3 /. The electrocentrifugal installation includes a lower additional section of the stages of the impellers, pumping fluid from the lower reservoir into the above-packer space of the well. The liquid of the lower layer arrives at the reception of an additional section of the pumping unit through the inlet pipe with a packer. From the last stage of the additional section, the liquid of the lower layer through the channels in the body enters the well above the packer, where it is mixed with the liquid of the upper layer. A mixture of the products of the upper and lower layers enters the receiving module of the main pump and is pumped to the surface through the tubing string. The main pump and the additional section are located on the same shaft with a submersible electric motor (SEM) and are separated from it by hydraulic protections.

The described installation, selected as a prototype, cannot be used to pump the separated water of the upper layer into the underlying horizon.

The aim of the invention is the provision of injection separated in the well of produced water into the underlying absorbing horizon.

This goal is achieved by the fact that in the known device containing an electric centrifugal pump with an additional section located below the submersible electric motor on the same shaft with it and having a channel in the housing for the outlet of the lower formation fluid into the above-packer space of the well, hydroprotection, a receiving pipe for selecting the lower formation fluid with a packer installed between the upper and lower layers, between the inlet pipe for the selection of liquid of the lower layer and an additional section of the pump installed inlet pipe The first one ends with a passage plunger and having a partition above which there is a channel for the entry of stratified incidentally produced water into the receiving part of the additional section of the pump, and below the partition there is a channel connected to the channel at the output of the additional section by means of a flat pipe, and the receiving branch pipe of the installation has the upper part of the cylinder, forming a friction pair with the plunger of the pipe and ending with a separator funnel, the upper edge of the separator funnel being located above the stratified inlet channel ysya water into the inlet pipe.

In figures 1, 2, 3 and 4 shows a diagram of the proposed device. An electric centrifugal installation was lowered into the well on the tubing string 1, consisting of an upper (main) pump 2, a submersible motor 3, an additional section 4, a receiving module 5, hydraulic shields 6 and 7 located on both sides of the electric motor 3. To the submersible electric motor 3 suitable electric cable 8. At the entrance to the additional section 4 of the pump, a pipe 9 with a partition 10 is suitable from below, directly above and below which side channels 11 and 12 are made in the pipe 9. At the bottom of the pipe 9 ends a passage plunger By a meter 13. To the casing of the additional section 4 of the pump, at the level of the location of the upper impeller 14, a flat pipe 15 is connected, which lower end enters the channel 12 of the pipe 9.

The plunger 13 is sealed in the cylinder 16 of the receiving pipe 17, installed in the well with the help of a packer 18, separating the productive 19 and absorbing 20 layers. In the upper part of the pipe 17 ends with a funnel-separator 21. The pipe 15, fixed to the housing of section 4, is made flat to reduce the dimensions of the installation.

In figures 3 and 4 shows the installation options in the well with a drilled sidetrack 22.

The operation of the device is as follows. Initially, the intake pipe 17 with the cylinder 16 and the separator funnel 21 is lowered into the well. The pipe 17 is installed in the well with the help of a packer 18 located between the productive 19 and the absorbing 20 layers.

Next, an electric centrifugal pump with a pipe 9, a through-flow plunger 13 and a flat pipe 15 is lowered into the well. A pipe 9, with its through-flow plunger 13, enters the cylinder 16 of the nozzle 17. In this case, the separator funnel 21 acts as a centralizer, allowing the nozzle 17 to be aligned coaxially in the well and the input of the plunger 13 into the cylinder 16 of the pipe 17. The plunger 13 together with the cylinder 16 form a sealing pair of friction, which allows, on the one hand, to separate the receiving cavity of the lower section 4 of the pump from the over-packer space, and on the other, to eliminate l transmit vibration of the pump to the packer 18 and prevent the gradual depressurization of the latter.

The operation of the installation is as follows. In the above-packer space at the bottom of a watered well, there is always a column of produced water. In this regard, the oil phase from the reservoir 19 exits through the perforations in the wellbore in the form of droplets that float up in the upward continuous stream of the aqueous phase. The oil-water mixture of the reservoir 19, falling into the gap between the separator funnel 21 and the well wall, increases its speed and allows you to effectively separate water from oil beyond the upper edge of the separator funnel. In this case, the funnel 21 plays the role of a labyrinth type oil separator. The aqueous phase, freed from the pop-up oil phase, as a heavier medium, moves down to the channel 11 of the pipe 9 and is received by the lower section 4 of the pump. At the exit from the last stage of this section, the injected aqueous phase enters the flat pipe 15, enters the pipe 17 through the channel 12 and then is pumped into the under-packer space, that is, into the absorbing aquifer 20.

The oil phase from the wellbore due to lower density enters the receiving module 5 of the pump and is pumped to the surface by the upper section 2.

The installation provides hydraulic protection 6 and 7, protecting the submersible motor 3 from liquid from both sides.

Installation of a tight friction pair (plunger 13-cylinder 16) allows, firstly, to remove vibration loads on the packer 18 and its gradual depressurization, and secondly, to lift the pump 2 without the operation of breaking the packer and breaking the pump casing. In this case, the packer is broken by an additional descent of the fishing tool.

In those cases when a sidetrack 22 has been drilled to the well (Fig. 3), the separator funnel 21 is located above the sidetracking point. In this case, two options are available for pumping out the separated water. According to the first embodiment, water injection is carried out in the same way as shown in FIG. 1 to the underlying absorbing horizon 20. According to the second embodiment, water injection can be carried out in the reservoir 19 with the goal of displacing oil from the center to the bottom of the sidewall and increasing the oil recovery coefficient (Fig. 4).

The technical and economic advantage of the proposed installation is the ability to utilize associated produced water into an absorbing horizon without raising it to the surface, as well as increasing the final oil recovery from the reservoir by means of sidetracking.

Information sources

1. Patent No. 2284410 of the Russian Federation, MKP E21B 43/40. Well pumping unit for oil production and water injection into the reservoir. 2006. Bull. Number 27.

2. Patent No. 63864 of the Russian Federation, MKP E21B 43/38, E21B 43/40, 2006. Installation of a borehole sucker rod pump with a double-acting pump / Valovsky V.M., Basos G.Yu., Valovsky K.M. et al. 02/01/2007 Publ. 06/10/2007 Bull. No. 16.

3. Patent No. 69146 of the Russian Federation, IPC E21B 43/14, 2006. Installation for simultaneous and separate operation of two layers / Pavlov EG, Valeev MD, Sergienko VN et al. 04/13/2006. Publ. 12/10/2007. Bull. Number 34.

Claims (1)

Installation of an electric centrifugal pump for oil production and water injection into a formation, comprising an electric centrifugal pump with an additional section located below the submersible electric motor on the same shaft with it and having a channel in the housing for the outlet of the lower formation fluid into the above-packer space of the well, hydraulic protection, a receiving pipe for fluid withdrawal the lower reservoir with a packer installed between the upper and lower reservoirs, characterized in that, in order to ensure the possibility of oil production and injection separated in the well formation of inlet water to the underlying absorbing horizon, an inlet pipe is installed between the inlet pipe for the selection of liquid of the lower reservoir and the additional section of the pump, which ends with a passage plunger and has a partition above which there is a channel for the stratified passing-produced water to enter the receiving part of the additional section of the pump, and below the partition there is a channel in communication with the channel at the outlet of the additional section using a flat pipe, and the receiving pipe of the installation has a cylinder in the upper part, a friction pair connecting with the plunger of the pipe and ending with a separator funnel, the upper edge of the separator funnel being located above the channel for the stratified water to enter the inlet pipe.

Images