RU2399756C1 - Development method of gas well without packer in conditions of abnormally low formation pressures - Google Patents

Abstract

FIELD: oil and gas industry. ^ SUBSTANCE: invention refers to development of gas wells in conditions of abnormally low formation pressures - ALFP, especially in conditions of decreased formation pressures. Development method of gas well without packer in ALFP conditions involves gas supply from operation wells to booster compression station - BCS, where gas is compressed to the pressure of 5.0-5.5 MPa. After BCS the gas is supplied to gas processing facility - GPF, where gas is cleaned from mechanical impurities and water, and gas is supplied under pressure of 3.0-4.0 MPa to cluster site of the developed well and then to booster station to which process water is pumped at the same time. The obtained liquid-gas mixture is compressed to the value of 7.0-10.0 MPa. After that gas-liquid mixture is supplied to separator where gas-liquid mixture is separated into high pressure gas and liquid. Liquid is supplied to pump station, and high pressure gas is supplied to ejector to which there also supplied is foam-forming liquid - FFL. Aerated foam-forming liquid - AFFL obtained on ejector is supplied to flexible pipe - FP of coil tubing unit which is lowered to tube space of the well with stops in every 50-100 m. At each FP burial step the supply of FFL to ejector is stopped, and high pressure gas is supplied to FP by passing the ejector, forcing away damping liquid and AFFL to day surface and by performing well ventilation till gas influx is obtained from productive formation. After FP is buried to the depth of 200-300 m together with supply of AFFL thereto there supplied to after-tube space of the developed well is gas from GPF with pressure of 3.0-4.0 MPa. After gas influx is obtained, the well is developed till it is brought to process mode; after that FP is removed from well, and well is brought into operation. ^ EFFECT: reducing the time required for well development and providing influx from formation of gas well without packer in ALFP conditions with abnormal coefficient lower than 0,2. ^ 1 dwg, 1 ex

Description

The invention relates to the oil and gas industry, in particular to the development of gas wells in conditions of abnormally low reservoir pressure - AAP, especially in conditions of low reservoir pressure with an anomaly coefficient below 0.2.

A known method of well development, including replacing the kill fluid with a lightweight fluid, calling up the inflow, running the well for a flare [RF Patent No. 2109934].

The disadvantage of this method is the low efficiency of the call inflow from the wells in the conditions of the API and the impossibility of calling it with an anomaly coefficient below 0.2.

A well-known method of well development, including replacing the kill fluid with lightweight fluid, supplying high pressure gas to a flexible pipe — GT of a coiled tubing installation, inflow challenge, drilling a well for a flare [RF Patent No. 2235868].

The disadvantage of this method is the low efficiency of the call inflow from the wells in the conditions of the API and the impossibility of calling it with an anomaly coefficient below 0.2.

The challenge facing the creation of the invention is to increase the reliability and efficiency of gas well development under the conditions of oil production with an anomaly coefficient below 0.2.

The achieved technical result, which is obtained as a result of the creation of the invention, consists in providing the possibility of inducing inflow from the formation of a gas well without a packer in the conditions of AAP with an anomaly coefficient below 0.2 and in reducing the time for its development.

The task and technical result are achieved by the fact that when developing a well under the conditions of oil production, gas from production wells is fed to a booster compressor station - DKS, where gas is compressed to a pressure of 5.0-5.5 MPa, after DKS gas is supplied to the complex gas treatment unit - UKPG, where the gas is cleaned of mechanical impurities and water, and under a pressure of 3.0-4.0 MPa, gas is supplied to the well pad of the well being developed and then to the booster installation, into which technical water, the obtained gas-liquid mixture, are simultaneously pumped imitate to a value of 7.0-10.0 MPa, after which the gas-liquid mixture is sent to a separator, where the gas-liquid mixture is separated into high-pressure gas and liquid, the liquid is sent to the pump unit, and the high-pressure gas is fed to the ejector, which is simultaneously fed foaming fluid - ALF, aerated foaming fluid obtained on an ejector - APOF is fed to the coiled tubing unit GT, which is lowered into the borehole space with stops every 50-100 m, at each stage of the GT deepening under Ignore the coolant to the ejector, and the high-pressure gas is supplied to the GT, bypassing the ejector, squeezing out the kill fluid and ALS onto the surface and purging the well until gas is received from the reservoir, after deepening the GT by 200-300 m at the same time as APOG supply gas to the annulus of the well being developed from the gas treatment unit at a pressure of 3.0-4.0 MPa, after receiving the gas inflow, the well is worked out until it is put into production mode, after which the hydraulic wells are removed from the well, and the well is introduced into pluatatsiyu.

The drawing shows a diagram for implementing this method.

The method is implemented as follows.

Low pressure gas of 0.8-1.0 MPa in value from production well 1 is fed through pipeline 2 to the booster compressor station, where it is compressed to a pressure value of 5.0-5.5 MPa, after the booster compressor gas is supplied to the gas treatment plant, where the gas is cleaned of mechanical impurities and dried from water, and under a pressure of 3.0-4.0 MPa, gas is supplied through pipeline 3 to the well pad of the well being developed and then to booster unit 4, at the same time process water is supplied from pumping unit 5 through pipeline 6 to winter time - methanol water or an aqueous solution of potassium, calcium or sodium chlorides. In the booster installation 4, gas and process water are mixed to form a gas-liquid mixture, the gas-liquid mixture is compressed to a pressure of 7.0-10.0 MPa, which exceeds the current reservoir pressure, the high-pressure gas-liquid mixture is fed via line 7 to the separator 8. Here, the gas-liquid mixture is separated on liquid and gas media. The liquid from the separator 8 through the pipeline 9 is again sent to the pump unit 5 for reuse, and the high pressure gas of 7.0-10.0 MPa is fed through the pipeline 10 to the ejector 11. At the same time, the ejector 11 from the pumping unit 12 is fed through the pipeline 13 Pozh, in winter - non-freezing foaming liquid - NPOZH. You can use process water with OP-10 or process water with sulfanol as a lifeguard agent. An aqueous solution of calcium chloride or another salt with OP-10 or with sulfanol can be used as an NPOS. Then obtained on the ejector 11 APOZ through pipeline 14 serves in GT 15 coiled tubing installation 16 and then into the annular gap 17 between GT 15 and the lift column 18 of the well being developed 19. GT 15 is lowered into the lift column 18 in steps with stops of 50-100 m each stage, with the simultaneous supply of AOF through it, which displaces the kill fluid located in the well being developed 19, through the annular gap 17 along the flow line 20 and the pipe 21 into the reservoir 22 for collecting the kill fluid. At each stage of the deepening of GT 15, the supply of coolant to the ejector 11 is stopped, and high-pressure gas is supplied to the GT 15 bypass 23, bypassing the ejector 11, squeezing the jamming fluid and ALS onto the surface and purging the well being developed 19. After deepening the GT 15 by 200 -300 m simultaneously with the supply to GT 15 APOZH supply gas from the gas treatment unit with a pressure of 3.0-4.0 MPa bypass pipe 24 into the annular space 25 of the well being developed 19, formed between the lift 18 and production 26 columns, facilitating the call of inflow from the productive P flipper 27.

After receiving a gas inflow, the well being developed 19 is worked out until it is put into production through the flow line 20 and flare line 28, after which the GT 15 is removed from the well being developed 19, and the well being developed 19 is put into operation.

The gas supply to the booster unit 4 from the booster compressor station, and not from the neighboring production well 1, is necessary to create the productivity of the booster unit 4 required when developing the well 19, which the neighboring production well 1 due to low reservoir pressure equal to 0.8-1.0 MPa, cannot provide.

The displacement of the kill fluid through the annular gap 17 is carried out due to the lack of communication of the annular space 25 of the well being developed 19 with the flow 20 and flare 28 lines.

By supplying gas to the annular space 25 of the well being developed 19, the suppression fluid is displaced from the annular space 25 into the lift string 18 without being forced into the producing formation 27, without being contaminated and the development conditions of this well 19 are worsened. In the case of gas supply to the lowering depth of GT 15 less 200-300 m high probability, as shown by the practice of causing inflow from gas wells of the Vyngapurovskoye field, forcing and absorbing the killing fluid by the reservoir 27.

The gas supply to the annular space 25 of the well being developed 19 from the gas treatment facility with a pressure lower than that of the separator 8 is explained by the need to supply gas to the annular space 25 of the well being developed 19 with a higher flow rate than booster unit 4 can provide and the separator 8 can pass through it.

If there is no removal of the kill fluid to the day surface, which is possible when the kill fluid is absorbed by the reservoir 27, GT 15 is lifted and high pressure gas continues to be supplied to it. Lift GT 15 is carried out until the recovery of the fluid killing from the well being developed 19 to the day surface is restored.

Due to the low reservoir pressures, it is not allowed to force the kill fluid into the reservoir 27.

Due to the presence of 19 perennially frozen rocks in the mouth zone of the well being developed and low ambient temperatures in the winter, when developing a well for heating process water and drilling fluids, as well as ground and wellhead equipment, a steam heating unit 29 is used.

An example of the implementation of the proposed method at well No. 127 of the Vyngapurovsky field.

Gas from a production well with a pressure of 0.8 MPa was supplied to the BCS, where it was compressed to a pressure of 5.0 MPa. After that, the gas was supplied to the gas treatment plant, where it was dried from the liquid and purified from mechanical impurities. After that, gas under a pressure of 3.5 MPa, the maximum allowable pressure of this pipeline, was supplied through the pipeline to the cluster site and then to the booster installation, while technical water was supplied through the pipeline from the pump installation to it. In the booster installation, gas and process water were mixed, a gas-liquid mixture was formed, the mixture was compressed to a pressure of 9.0 MPa, which exceeds the current reservoir pressure in the well being developed. The high-pressure gas-liquid mixture was fed to a separator. Here, the gas-liquid mixture was separated into liquid and gas media. The liquid from the separator was again sent through the tank to the pump unit, and high-pressure gas of 9.0 MPa was fed to the ejector. At the same time, coolant was applied to the ejector. Then, the APOA obtained by mixing high-pressure gas and POC was fed into the hydraulic core of the coiled tubing installation and then into the annular gap located between the hydraulic core and the lift column of the well being developed. Circulation through the hydraulic circuit and the annular gap was carried out to ensure a higher upward flow rate and to facilitate the displacement of the kill fluid, and then the ALS. At the same time, the annular space of the well being developed was specially blocked with the help of a valve and was not communicated with flow and flare lines. GTs were lowered into the inner cavity of the lift string, into the borehole space, in steps with stops every 100 m. During the descent, the GT supplied to the well of the ALS displaced the killing fluid in the well to the surface to collect the killing fluid. After every 100 m, the well was purged, stopping the supply of coolant to the ejector and supplying high-pressure gas to the well bypassing the ejector, squeezing the ALS onto the day surface. After deepening the GT by 300 m, simultaneously with the supply to the APOZ GT, gas was supplied from the gas treatment unit to the annular space of the well being developed through the bypass pipeline connecting the pipeline from the gas treatment station to the annular space of the well being developed.

After receiving the gas inflow, the well being developed was worked out until it was put into operation through the flow and flare lines. Then the GT was removed from the well being developed, after which the well being developed was put into operation.

The proposed method provides a reliable development of a gas well without a packer in the conditions of the API with an anomaly coefficient below 0.2. At the same time, the duration and cost of well development work is reduced and the fire and safety safety of the process is ensured.

Due to the stepwise displacement of the killing fluid from the well, it did not penetrate into the reservoir and did not pollute it, while maintaining the reservoir properties of the reservoir.

Due to the step-by-step purging of the well and additional gas supply to the annulus, a smoother, more “sparing” and easier gas flow from the reservoir is carried out.

Claims (1)

A method of developing a gas well without a packer under conditions of abnormally low reservoir pressure is an AAP, in which gas from production wells is fed to a booster compressor station - DCS, where gas is compressed to a pressure of 5.0-5.5 MPa, after DCS, gas is supplied to the installation complex gas treatment - gas treatment plant, where the gas is cleaned of mechanical impurities and water, and at a pressure of 3.0-4.0 MPa, gas is supplied to the well pad of the well being developed and then to the booster installation, into which technical water and the resulting gas-liquid mixture are simultaneously pumped they are compressed to a value of 7.0-10.0 MPa, after which the gas-liquid mixture is sent to a separator, where the gas-liquid mixture is divided into high-pressure gas and liquid, the liquid is sent to the pump unit, and the high-pressure gas is fed to the ejector, which is simultaneously fed foaming fluid - ALF, aerated foaming fluid obtained on an ejector - APOF is fed into a flexible pipe - HT of a coiled tubing installation, which is lowered into the borehole space with stops every 50-100 m, at each stupa and deepening the GT, the flow of coolant to the ejector is stopped, and high-pressure gas is supplied to the GT, bypassing the ejector, squeezing the kill fluid and ALS onto the surface and purging the well until gas is supplied from the reservoir, after deepening the GT by 200-300 m simultaneously by supplying it to the APOZ, gas is supplied to the annular space of the well being developed from the gas treatment unit at a pressure of 3.0-4.0 MPa, after receiving the gas inflow, the well is worked out until it is put into production mode, after which the GT is removed from the well, and kvazhinu commissioning.

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