RU2789535C1 - Method for removing condensate or well killing fluid from a plugged gas well, a method for operating a gas well and preventing its “self-plugging” and a downhole device for their implementation - Google Patents

Abstract

FIELD: mining industry.

SUBSTANCE: invention relates to the development of gas and gas condensate fields. In particular, a method for removing liquid from a killed gas well with the equipment of a tubing string is claimed, including pumping compressed gas from the surface into the well, while the compressed gas is charged into the annular space through the wellhead fittings or the sub-packer area of the annular space through the tubing string in the case of supplying the tubing string with a packer and a check valve, which is installed below the diffuser and the confuser nozzle inside the tubing string, for its subsequent supply to the tubing string when the tubing string is open through the communication channel of the annular space with the confuser nozzle, located under the diffuser, and the annular space is charged with the displacement of the liquid being removed into the bottom-hole zone of the formation. The method for operation of a gas well with tubing string equipment and prevention of its “self-plugging” and a downhole device for the implementation of these methods are also disclosed.

EFFECT: increase in the efficiency of removing liquid from a gas well due to the organization of an ejection effect in the well, in which mixing of two media occurs under conditions when one of them, being under pressure, affects the other and carries it in the desired direction.

5 cl, 5 dwg

Description

The invention relates to the development of gas and gas condensate fields, namely: to a method for removing unwanted fluid that accumulates in a gas well during operation, for example, gas condensate, leading to a decrease in gas flow rates and even "self-killing" of the well, to a method for operating a gas well and preventing it "self-killing", to the method of developing a gas well after killing, as well as to a downhole device for implementing these methods.

An analogue of the proposed method for removing fluid from a gas well prone to "self-silencing" and the proposed method for operating a gas well and preventing its "self-silencing" is a method for operating flooded gas wells (RF patent No. 2484239, op. 10.06.2013 [1]), including perforation production string below the level of the current gas-water contact; lowering an additional tubing string (tubing string) of small diameter into the well with a downhole equipment assembly lowered below the operating interval, consisting of a packer that serves to separate the internal space of the production string filled with gas and filled with water, a working chamber designed to accumulate condensed on downhole fluid; implementation of high-pressure gas supply to the tubing string of small diameter from a compressor installed on the day surface or a donor well with a wellhead pressure higher than the hydrostatic pressure at an absolute hypsometric mark corresponding to the location of the technological holes of the receiving well by more than 10 atm; squeezing with excess pressure gas the liquid condensing at the bottomhole and accumulating in the working chamber into the water-saturated interval located below the operational productive interval. The principle of operation consists in periodically displacing into the water-saturated interval of the reservoir (under-packer space) the liquid accumulating in the working chamber by excess gas pressure, which is created by the compressor unit and transferred to the working chamber through the inner space of the small-diameter tubing.

The method [1] is not technologically advanced enough, since changing the well design - perforating the production string below the level of the current gas-water-oil contact into the water-saturated interval of the reservoir will further complicate the transition to the underlying productive horizon and exclude alternative methods of operating the facility without repairing the string. The operation of the well in this way will most likely soon lead to contamination of the perforation channels and the porous medium of the bottomhole formation zone (BFZ) of the receiving water-saturated horizon, which will require very complex work to dismantle the system and decolmatize. At the wellhead, it is necessary to have a separator and a compressor on a permanent basis for servicing the well, and the compressor requires a constant source of electricity to drive it, while most gas wells are not equipped with a transformer and power supply line.

Also, the disadvantage of the method [1] lies in its complexity, due, among other things, to the use of complex downhole equipment, including an additional string of tubing of small diameter. The installation of a coaxial layout leads to an increase in the cost of the structure, as well as wellhead fittings.

The prototype of the proposed method for removing liquid from a gas well prone to "self-silencing" and the proposed method for operating a gas well and preventing its "self-silencing" is a method for operating wells at the final stage of development of gas deposits (RF patent No. 2733585, op. 05.10.2020 [2 ]), which includes the supply of gas from the surface using a mobile compressor unit (MCU) under the shoe of the tubing column with the accumulated liquid, and inside the tubing string, dispersing devices are installed in the form of rings with a cone-shaped surface every 200-300 m from the shoe, while the height of the ring of the dispersant is 3-9 mm, the width is 11-41 mm, the confuser taper angle is 70-90°, the cone angle of the diffuser is 30-60°, the outer diameter of the dispersant ring is equal to the inner diameter of the tubing string, and the ratio of the inner diameter of the tubing string to the height dispersant is 8.8-11.6.

The disadvantages of the prototype [2] include the lack of efficiency in relation to gas wells that are at the final stage of field development, when a significant part of the fund can have gas flow rates from 10 to 30 thousand m ³ /day. and reservoir pressure from 2.8 MPa to 8.0 MPa ("Instruction for the integrated study of gas and gas condensate reservoirs and wells" edited by G.A. Zotov, Z.S. Aliyev. -Moscow, Nedra. 1980. Chapter 9, section 9.2 Technological mode of operation of wells in the presence of a sand plug or liquid column at the bottomhole, pp. 277-279), while the method [2], according to the description, is used in wells with a gas flow rate of 55 thousand m ³ / day Despite the improvement of liquid and gas removal processes by said devices in the form of rings shown in the description [2], in general, the method [2], according to the applicant, is reduced to blowing the accumulated liquid from the bottomhole through the lift pipes with gas injected downhole by a compressor. The well operation method [2] is periodic in nature, since MCU, by definition, is supplied to the wellhead only as needed, namely: for the period of removal of the accumulated fluid. Then the operation of the gas well continues until the next period of removal of the accumulated fluid. At the same time, devices in the form of rings installed in the well every 200-300 meters make it difficult to operate, increasing the hydraulic resistance of the lift.

The problem to be solved and the expected technical result are to create an effective method for removing fluid from a gas well prone to "self-killing", a field that is at the final stage of development, when a significant part of the well stock has gas flow rates from 10 to 30 thousand m ³ /day and reservoir pressure from 2.8 MPa to 8.0 MPa, due to the organization of the ejection effect in the well, in which the mixing of two media occurs under conditions when one of them, being under pressure, affects the other and entrains it in the required direction; according to the applicant, it is as a result of the ejection effect that the liquid accumulated in the well rises to the surface in the form of a fog - aerosols - a dispersed system consisting of liquid droplets suspended in a gaseous medium.

At the same time, the proposed method for removing liquid from a plugged gas well is easily transformed into a technology for operating a gas well and preventing its “self-killing”, using downhole equipment already in the well.

The problem is solved by the fact that a method is proposed for removing liquid from a plugged gas well with special tubing equipment, including injection of compressed gas from the surface into the well, characterized in that the annular space is charged with compressed gas through the wellhead fittings for its subsequent supply to the tubing with open tubing along a communication channel of the annular space with a confuser nozzle located under the diffuser, and the annular space is charged with the displacement of the removed liquid into the bottomhole formation zone.

When removing fluid from a well equipped with a tubing with a packer and a check valve, the under-packer area of the annular space is charged with compressed gas by injecting compressed gas into the tubing with the check valve closed, which opens as the liquid rises to the surface when compressed gas is supplied to the tubing from the under-packer area of the annulus .

Additionally, for the prevention of “self-killing” of a well equipped with tubing with a packer and a check valve, during further operation, as liquid appears in the well, the produced gas that has charged the under-packer area of the annular space is fed into the tubing with the tubing open through the communication channel of the under-packer area of the annular space with a confuser nozzle located under the diffuser, with the check valve closed, which opens as the liquid rises to the surface when the produced gas is supplied to the tubing from the under-packer area of the annular space, after which the well is operated in the normal mode.

Also, the problem to be solved and the expected technical result are to create an efficient and technologically advanced method for operating a gas well and preventing its “self-killing” by connecting the formation energy, which is carried by the formation gas. At the same time, the proposed method can be implemented as a simple continuation of the technology for removing fluid from a dead well, using downhole equipment already present in the well.

Also, the problem is solved by the fact that a method is proposed for operating a gas well with tubing equipment and preventing its “self-killing”, characterized in that in order to remove liquid from a plugged gas well, by injection from the surface through the wellhead, the annular space is charged with compressed gas for its subsequent supply to the tubing when the tubing is open through the communication channel of the annular space with a confuser nozzle located under the diffuser, the annular space is charged with the displacement of the removed fluid into the bottomhole formation zone; and during further operation, as liquid appears in the well, the produced gas that charges the annular space during the operation of the well is supplied to the tubing with the tubing open through the communication channel of the annulus with a confuser nozzle located under the diffuser to lift the liquid from the tubing to the surface, after which operation continues wells in normal operation.

An analogue of the proposed downhole device for implementing a method for removing fluid from a plugged gas well, a method for operating a gas well and preventing its "self-killing" and a method for developing a gas well after killing is a device for removing fluid from the bottom of the well (RF patent No. 2484239, op. 10.06.2013 [1]), containing the production string, perforated below the level of the current gas-water contact; lowered into the well the main tubing string and an additional string of small diameter tubing with downhole equipment lowered below the operating interval, consisting of a packer to isolate the internal space of the production string filled with gas and water; a working chamber designed for the accumulation of liquid condensing on the bottom; borehole filter to prevent mechanical impurities from entering the working chamber; bypass valve for separating the internal space of the working chamber and the annulus; check valve for separating the inner space of the working chamber and the space under the packer; an inlet valve for separating the internal space of the working chamber and the internal space of tubing of small diameter; a high-pressure gas supply source to a string of small-diameter tubing for pushing excess pressure gas of the liquid accumulated in the working chamber into a water-saturated interval located below the production production interval; a separator for gas drying installed on the day surface, pressure gauges for monitoring the wellhead pressure of the main and small tubing strings, shut-off and control devices for regulating gas flow through the main and small tubing strings, a control unit for monitoring and controlling the process according to a given algorithm.

The device [1] is complex, in particular, due to the use of a coaxial layout with appropriate wellhead fittings. The reliability of the device [1] in the downhole structure is significantly reduced by the presence of a packer and a large number of valves (bypass valve, check valve, shut-off valve, circulation valve), since in the event of even a slight leak between the string and the sealing element of the packer or failure of any of the valves, the work device will be broken.

To operate the device [1] on a permanent basis, it is necessary to have a separator and a compressor at the wellhead, and the compressor for its drive requires a constant source of electricity, while most gas wells are not equipped with a transformer and a power supply line.

The prototype of the proposed downhole device for implementing a method for removing liquid from a dead gas well, a method for operating a gas well and preventing its "self-killing" and a method for developing a gas well after killing is a device for removing liquid from the bottom of the well by supplying compressed gas from the surface under the shoe of the lifting string (RF patent No. 2733585, op. 05.10.2020 [2]), including dispersant devices installed inside the lifting column in the form of rings with a cone-shaped surface every 200-300 m from the shoe, while the height of the dispersant ring is 3-9 mm, the width - 11-41 mm, confuser taper angle - 70-90°, diffuser taper angle - 30-60°, the outer diameter of the dispersant ring is equal to the inner diameter of the lifting column, and the ratio of the inner diameter of the lifting column to the height of the disperser is 8.8-11, 6.

The disadvantages of the prototype device [2] include the lack of efficiency in relation to gas wells that are at the final stage of field development, when a significant part of the fund can have gas flow rates from 10 to 30 thousand m ³ /day. and reservoir pressure from 2.8 to 8.0 MPa, while the device [2], according to the description, is used in wells with a gas flow rate of 55 thousand m / day. Despite the improvement in the processes of removing liquid and gas by said devices in the form of rings, as shown in the description [2], in general, the process [2], according to the applicant, comes down to blowing the accumulated liquid from the bottomhole through the lift pipes with gas injected to the bottomhole by a compressor.

The problem to be solved and the expected technical result are to create an effective downhole device for implementing a method for removing liquid from a plugged gas well, a method for operating a gas well prone to "self-killing" and preventing its "self-killing", including at gas fields located at the final stage of development, and the method of developing a gas well after killing due to the organization of the ejection effect in the well (during the removal of liquid, well development) and by connecting the formation energy (during the operation of a gas well).

At the same time, the proposed device for removing fluid from a gas well, including for removing the killing fluid during well development, is transformed into a device for operating a gas well and preventing its “self-killing”, using downhole equipment already in the well.

The problem is solved by the fact that the proposed downhole device for implementing a method for removing liquid from a plugged gas well, a method for operating a gas well and preventing its “self-killing” is a confuser nozzle installed inside the tubing under a diffuser, having a communication channel with the annular space, and the device is made with the possibility of charging the annular space with gas both from the surface through the wellhead fittings with the removal of the removed liquid into the bottomhole formation zone, and with the gas coming from the formation during the operation of the well.

The tubing can additionally be equipped with a packer with a check valve, and the device is designed to charge the under-packer area of the annulus with gas both from the surface through the wellhead fittings with the removal of the removed liquid into the bottomhole formation zone, and with the gas coming from the formation during the operation of the well.

It is desirable to use the claimed methods and device in conjunction with cleaning the perforation channels and the bottomhole zone of the well according to the patents of the Russian Federation No. The inventive method for removing fluid and the inventive device can be used, for example, after killing a well according to RF patent No. 2545197.

The claimed methods and device are illustrated in figures 1-5.

Fig. 1 illustrates the proposed device and charging with compressed gas of the annulus of a gas well plugged with gas condensate or, for example, a killing liquid, in preparation for work;

Fig. 2 illustrates the proposed device in the presence of a packer with a check valve in the tubing and charging the annulus of such a gas well with compressed gas, plugged with gas condensate or, for example, killing fluid, in preparation for work;

Fig. 3 is an enlarged scale of the confuser nozzle under the diffuser during preparation for operation of the device according to FIG. 2;

Fig. 4 - scheme of operation of the device with a packer and a check valve;

Fig.5 is an enlarged scale of the scheme of operation of the confuser nozzle under the diffuser of the device according to Fig. 4.

In FIG. 1-3:

1 - tubing

2 - annulus

3 - confuser nozzle

4 - diffuser

Channel 5

6 - packer

7 - check valve.

White color and white arrows indicate gas: in Fig. 1, 2, 3 - compressed nitrogen, displacing liquid in the bottomhole zone when preparing the device for operation (tubing 1 is closed - Fig. 1; tubing 1 will be closed after charging is completed, illustrated in Figs. 2, 3); in fig. 4, 5 - compressed nitrogen or produced gas supplied from the under-packer area of the annulus 2 to tubing 1 (tubing 1 is open - Fig. 4, 5).

Light gray and light gray arrows indicate liquid.

White with a light gray speck (Fig. 4, 5) denotes an aerosol - a dispersion of liquid in gas, formed during gas ejection from the annular space into the tubing with accumulated liquid (gas condensate or killing liquid).

The proposed device operates as follows, to implement the proposed methods.

1. To remove fluid from a plugged (gas condensate or killing liquid) gas well (independent claim 1 of the formula):

- injection of compressed gas into the well from the surface to charge the annular space 2 through the wellhead fittings (injection of compressed gas directly into the annular space 2 - Fig. 1), with the removal of the removed liquid in the bottomhole zone (tubing 1 is closed - Fig. 1) with subsequent shutdown of the source compressed gas after charging the annulus 2;

- supply (ejection) of compressed gas from the annular space 2 to the tubing 1 with the removed liquid at an open tubing 1 through the channel 5 of the connection of the annular space 2 with the confuser nozzle 3 located under the diffuser 4;

- formation in the process of said ejection of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in the compressed gas;

- rise of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in compressed gas from tubing 1 to the surface.

Since the specific gravity of the generated aerosol does not exceed 0.05 g/ ^cm3 , the formation pressure of 40 atm - 60 atm (4 MPa - 6 MPa) is sufficient to lift the aerosol column from a depth of 3000 m to the surface into the collection system.

2. To remove fluid from a dead gas well equipped with tubing 1 with packer 6 and check valve 7 (depending on claim 2 of the formula) - FIG. 2, 3:

- injection of compressed gas from the surface to charge the under-packer area of the annular space 2 through the wellhead fittings (injection of compressed gas into the tubing 1 and further through the diffuser 4, confuser nozzle 3 and channel 5 into the under-packer area of the annulus 2 - Fig. 2, 3), with the displacement of the removed liquid in the PZP; with closed check valve 7;

- then tubing 1 close and turn off the source of compressed gas;

- supply (ejection) of compressed gas from the under-packer area of the annulus 2 - FIG. 4, 5 - in the tubing 1 with the liquid to be removed with the tubing 1 open through the channel 5 for connecting the under-packer area of the annular space 2 with the confuser nozzle 3 located under the diffuser 4;

- check valve 7 opens - fig. 4, 5 - as the liquid rises to the surface when compressed gas is supplied (ejected) into the tubing 1 from the under-packer area of the annular space 2, with the formation under the action of ejection of an aerosol - a dispersion of the removed liquid (gas condensate or killing liquid) in the compressed gas;

- rise of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in compressed gas from tubing 1 to the surface - fig. 4, 5.

3. To remove fluid from a plugged gas well equipped with tubing 1 with packer 6 and check valve 7, with the prevention of "self-killing" during further operation (dependent clause 3 of the formula):

- after performing the liquid removal operations according to the previous paragraph 2 - FIG. 2, 3, 4, 5 - additionally - for the prevention of "self-silencing" during further operation -

- as fluid appears in the well, the produced reservoir gas charges the under-packer area of the annulus 2 through the perforations in the production string (the annulus is closed, the tubing 1 is open);

- the produced gas, which has charged the under-packer area of the annulus 2, under the action of the energy of the formation, is supplied to the tubing 1 with the tubing 1 open through the channel 5 of the connection of the under-packer area of the annulus 2 with the confuser nozzle 3 located under the diffuser 4, with the check valve 7 closed;

- formation of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in the produced gas (Fig. 4, 5);

- the rise of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in the produced gas from tubing 1 to the surface (Fig. 4, 5);

- the check valve 7 opens as the liquid rises to the surface during the supply (ejection) into the tubing 1 of the produced gas from the under-packer area of the annular space 2 (Fig. 4, 5);

- after removing the fluid that appeared in the well from the tubing 1, the well is operated in the normal mode.

4. For the operation of a gas well with tubing equipment and the prevention of its “self-killing” (independent clause 4 of the formula):

- to remove liquid from a plugged gas well by injection from the surface through the wellhead, the annular space 2 is charged with compressed gas, and the annular space is charged with the displacement of the removed liquid into the bottomhole formation zone (figure 1);

- supply (ejection) of compressed gas, which charged the annulus 2, into the tubing 1 with the tubing 1 open through the channel 5 of the annular space 2 with the confuser nozzle 3 located under the diffuser 4;

- formation in the process of said ejection of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in the compressed gas;

- rise of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in compressed gas from tubing 1 to the surface;

- during further operation, as fluid appears in the well, the produced formation gas charges the annulus 2 through the perforations in the production string (the annulus is closed, the tubing 1 is open);

- the produced gas, which charged the annulus 2, under the action of the energy of the formation is fed into the tubing 1 with the tubing 1 open through the channel 5 of the annular space 2 with the confuser nozzle 3 located under the diffuser 4;

- formation of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in the produced gas;

- rise of aerosols - dispersions of the removed liquid (gas condensate or killing liquid) in the produced gas from tubing 1 to the surface;

- after removing the fluid that appeared in the well from the tubing 1, the well is operated in the normal mode.

We give examples of the implementation of the claimed methods by the claimed device. Example 1 concerns legally significant claims of a group of inventions, i.e. sold on a well not equipped with a packer (p.p. 1, 4.5). Example 2 concerns dependent claims of a group of inventions, i.e. implemented on a well equipped with a packer and, accordingly, a check valve (items 2, 3, 6).

EXAMPLE 1

(Hereinafter, the ejector is the combination of a confuser nozzle with a diffuser)

The process of arrangement, development and operation of a gas well after the descent of the ejector

The flow line tubing 1 was tied through a separator with a gas collection manifold. To carry out the development process with a closed flow line, the annulus of the well was charged with nitrogen, raising the pressure to 3.8 MPa, i.e. 1 MPa above the formation level, which is necessary to remove fluid and put the well into operation. After stabilization of the pressure in the annulus at this value, the central valve on tubing 1 was opened and the wellhead source of compressed gas (nitrogen plant) was turned off. Thus, the annulus (annulus) space 2 was charged with compressed gas through the wellhead fittings (open annulus) and the subsequent opening of the tubing 1 to supply compressed gas to the tubing 1 through the channel 5 of the annular space connection with the confusing nozzle 3 located under the diffuser 4 - independent Clause 1 and Clause 4 of the claims of the group of inventions.

After 47 minutes, the arrival of packs of liquid with gas was recorded in the separator, the process proceeded at intervals of 5-7 minutes. The pressure in the annulus decreased to 3.1 MPa.

After 3 hours 40 minutes, the process of carrying out liquid with gas stabilized and became more uniform. The pressure in the annulus remained the same, which indicates the completion of the development process. Thus, the process of removing the liquid according to the independent claim 1 of the claims of the group of inventions was basically completed.

After 7 hours of operation, the liquid production significantly decreased and the well was producing gas with insignificant liquid production in the form of an aerosol. The pressure in the annulus stabilized at 2.7 MPa, which indicates that formation gas entered the wellbore. Formation gas thus produced during operation charged the annulus 2 for further operation of the well with the prevention of its "self-killing" - an independent claim 4 of the claims of the group of inventions.

Since the beginning of the operation, 9.5 m ³ of liquid has accumulated in the storage tank of the separator. The liquid was disposed of.

The well operation was monitored for 30 days. After 16 days of operation (self-killing time), 8.2 m ³ of liquid accumulated in the separator storage tank, and the well operation remained stable. The pressure in the annular space continued to stay in the range of 2.5-2.9 MPa, which indicates the normal stable operation of the ejector on the reservoir energy of the produced gas. Thus, during further operation, as fluid appears in the well, the gas that has charged the annulus 2, produced during the operation of the well, is supplied to the tubing 1 with the tubing 1 open through the channel 5 of the annular space 2 with the confuser nozzle 3 located under the diffuser 4 to lift the liquid from tubing 1 to the surface, after which the operation of the well continued in normal mode - an independent claim 4 of the claims of the claimed group of inventions.

Further monitoring of the well for 90 days confirmed the stability of operating parameters, no radical deviations were observed in the work.

Over the past period of 120 days, according to measurements, 2580 thousand m ³ of gas were produced with formation fluid in the amount of 48 m ³ .

EXAMPLE 2

The process of well completion, start-up and operation after the descent of the lift with a check valve, ejector and packer

The flow line tubing 1 was tied through a tee with a source of compressed gas (nitrogen plant) on the one hand and with a separator with a gas collection manifold on the other with the possibility of shutting down each line.

To carry out the process of removing liquid and putting the well into operation, nitrogen was pumped into tubing 1 from a source of compressed gas (nitrogen plant), raising the pressure to 4.5 MPa. Nitrogen through the tubing 1 and the confuser nozzle 3 of the ejector, when the valve 7 was closed, charged the under-packer annular area, pushing the liquid into the bottomhole zone. Thus, the annular space (under-packer annulus 2) was charged with compressed gas by injecting compressed gas into the tubing 1 with the check valve 7 closed - dependent claim 2 of the formula.

After stabilization of the pressure in the tubing system - the under-packer annulus, the source of compressed gas was turned off through the ejector. After the control hour exposure, the well was put into operation through a separator.

After 42 minutes, the liquid in the separator was recorded in the form of an aerosol. After 72 minutes, the pressure dropped to 4.0 MPa. The volume of liquid accumulated in the separator was 3.5 m ³ . Thus, when the compressed gas is supplied (entered) into the tubing 1 from the annular space (under-packer annulus 2), the liquid rises to the surface, with the opening of the valve 7 - dependent claim 2 of the formula.

The further process of well development to the separator was accompanied by a gradual decrease in pressure and accumulation of fluid in the separator.

Pressure stabilization at 3.3 MPa was noted 4.5 hours after the start of the well. The volume of accumulated liquid in the separator was 7.4 m ³ . Judging by the stability of the well operation, the under-packer annulus is intensively charged with formation gas, which maintains the stable operation of the ejector. The accumulated liquid was disposed of.

Monitoring of work with fixation of operating parameters continued for 120 days.

After 12 days (self-killing time), the well operation remained stable, and 3.9 m ³ of liquid accumulated in the separator reservoir. The operating pressure at the outlet was kept in the range of 2.8-3.2 MPa.

Over the past period of 120 days, according to instrumental measurements, 1984 thousand ^{m 3} of gas was produced. There were no failures in the well operation. Thus, in addition to preventing the “self-killing” of the well during further operation, as liquid appears in the well, the produced (during well operation) gas that has charged the annular space is supplied to the tubing 1 with the tubing 1 open through the annulus communication channel 5 (under-packer annulus 2) with a confuser nozzle 3 located under the diffuser 4, with the check valve 7 closed, which opens as the liquid rises to the surface when the gas produced (during the operation of the well) is supplied to the tubing 1 from the annular space (under-packer annulus 2), after which operation continues wells in normal mode - dependent claim 3 of the formula.

Claims (5)

1. A method for removing liquid from a plugged gas well with tubing string (tubing) equipment, including injection of compressed gas from the surface into the well, characterized in that compressed gas is used to charge the annular space through the wellhead fittings or the under-packer area of the annular space through the tubing in case supplying the tubing with a packer and a check valve, which is installed below the diffuser and the confuser nozzle inside the tubing, for its subsequent supply to the tubing with the tubing open through the communication channel of the annular space with the confuser nozzle located under the diffuser, and the annular space is charged with the displacement of the removed fluid into the bottomhole zone formation. 2. A method for removing fluid from a plugged gas well according to claim 1, characterized in that when removing fluid from a well equipped with a tubing with a packer and a check valve, the under-packer area of the annular space is charged with compressed gas with the check valve closed, which opens as the liquid rises to the surface when compressed gas is supplied to the tubing from the under-packer area of the annulus. 3. A method for removing liquid from a plugged gas well according to claim 2, characterized in that, in addition, to prevent "self-killing" of the well during further operation, as liquid appears in the well, the produced gas that has charged the under-packer area of the annular space is fed into the tubing with the tubing open via a communication channel under-packer area of the annular space with a confuser nozzle located under the diffuser, with a closed check valve that opens as the liquid rises to the surface when the produced gas is supplied to the tubing from the under-packer area of the annular space, after which the well continues to operate in normal mode. 4. A method for operating a gas well with tubing equipment and preventing its “self-killing”, characterized in that in order to remove liquid from a plugged gas well, the annular space is charged from the surface of the compressed gas by injection from the surface of the compressed gas through the wellhead fittings or the under-packer area of the annular space through the tubing if the tubing is equipped with a packer and a check valve, which is installed below the diffuser and the confuser nozzle inside the tubing, for its subsequent supply to the tubing with the tubing open through the communication channel of the annular space with the confuser nozzle located under the diffuser, the annulus being charged with the removal of the removed fluid into the bottomhole formation zone; and during further operation, as fluid appears in the well, which charged the annulus during the operation of the well, the produced gas is fed into the tubing with the tubing open through the communication channel of the annular space with the confuser nozzle located under the diffuser to lift the liquid from the tubing to the surface, after which they continue well operation in normal mode. 5. A downhole device for implementing a method for removing liquid from a plugged gas well according to claim 1, and a method for operating a gas well according to claim 4, including a confuser nozzle installed inside the tubing under the diffuser, having a communication channel with the annular space or the sub-packer area of the annulus, if available a packer on the tubing and a check valve under the diffuser and confuser nozzle, and the device is configured to charge the annular space or the under-packer area of the annular space with compressed gas from the surface through the wellhead fittings or through the tubing with the removal of the removed liquid into the bottomhole formation zone, as well as the gas produced from the formation during well operation.

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