WO2011159190A1 - Method for extracting gasified formation fluid - Google Patents

Abstract

The method for extracting gasified formation fluid can be used for extracting gasified formation fluid from deep wells. A continuous stream of fluid is generated by alternating the intake and output cycles of displacement pumps which are connected by pipe lines for the extracted fluid and for removing exhaust and casing-head gases, as well as by an electric power supply cable. A lower stage displacement pump is placed in the well 5-25 m below the static fluid level. The pressure is increased in the hermetically sealed well-casing annulus, in which the static fluid level is reduced to a level lower than the level at which the lower stage of the downhole displacement pump is situated. Fluid is taken in as a result of the difference in the increased and reduced pressures in the pipe line for removing exhaust and casing-head gases and in one of the working chambers of the pump in the lower stage of the assembly. The output from another chamber of the pump in the lower stage and the pumps in the remaining stages along the extracted fluid pipe line to pumps in higher stages is created by passing compressed gas into said pumps from the well-casing annulus. The intake of fluid by the working chambers of the higher pumps is provided for by the output of fluid from the working chambers of the lower pumps.

Description

^' METHOD FOR PRODUCING PLASTIC CARBONATED LIQUID

A method of producing a carbonated formation fluid relates to the field of oil production, and can be used for the production of carbonated formation fluid from deep wells.

 There is a method of producing liquid by sucker rod pumps (SHG) (Oil production reference. Authors: V.V. Andreev, K.R. Urazakov, V.U. Dalimov et al .; Edited by K.R. Urazakov, M. Nedra Business Center LLC, 2000, chapter 5)

 SHGN is expensive in manufacturing due to the use of high alloy steels and high-precision machining in manufacturing. Rather stringent requirements for tubing and tubing used in the extraction of sucker rod pumps, which makes their production and operation expensive.

 SHGN has rather stringent requirements for the content of mechanical impurities in the produced fluid (up to 3.5 g / l), as well as for the content of free gas (up to 25%).

 The strength of the rods and their deformation limit the depth of application of the SHGN with depths of up to 3200 m.

 During the production of liquids containing mechanical impurities in the SHGN, increased wear of the parts of the deep pump, as well as a breakage of the rods, is observed, which leads to unplanned stops and repairs.

 There is also a known method of fluid production by submersible electric multistage centrifugal pumps (ESP) (Oil production reference book. Authors: V.V. Andreev, K.R. Urazakov, V.U. Dalimov et al .; Edited by K.R. Urazakov M. LLC Nedra-Business Center, 2000, Chapter 6).

 During oil production with a high gas content in this way, gas plugs are formed in the working chambers of the pump, which leads to unplanned shutdowns in the production process. The requirements for the content of solids in oil are quite stringent - not more than 0.5 g / l. The use of ESP in wells with a flow rate of less than 40 cubic meters per day is impractical. The content of mechanical impurities leads to increased wear of the pump parts, because of which it is necessary to make fairly frequent repairs. When mining with ESP, there is a danger of electric shock to personnel, since a high voltage current is used to operate the submersible pump.

The closest in technical essence is the method according to patent RU 2325553 "Method and device for lifting fluids from wells", from 07.1 1.2006, published. 05/27/2008, IPC F04B47 / 00, including raising the liquid in the lower stage with a submersible electric pump, and raising the liquid in the upper stage with a deep rod pump (GSN), separating the liquid from the gas, and directing the gas into the annulus.

 The rise of the liquid in the lower stage is carried out to a height exceeding the level of the entrance to the main shaft, while part of the liquid is directed into the annulus through the holes made in the tubing string at a height exceeding the level of the entrance to the main shaft.

 The supply of liquid to the surface occurs intermittently, due to the alternation in the GHSN of the processes of absorption and pushing to the surface, which affects the performance of the method. The performance of the submersible electric pump is higher than the performance of the main gearbox, this leads to increased wear of the first. The pressure in the tubing pipes remains high enough, which requires their increased strength, this affects the weight of the entire structure. The pump is poorly suited for fluid production with a high content of solids. To supply a submersible electric pump, an electrical voltage is required, which is dangerous for people and animals, which imposes increased electrical safety requirements for this device.

 The objective of the proposed technical solution is the creation of easily integrated into the existing oil production system, an electrically safe, easy to operate and maintain method, which allows production from large and shallow depths of carbonated liquid with a high content of mechanical impurities and associated gas, and from wells with low debit, including .

The problem is solved by the method of producing reservoir carbonated fluid, including raising the fluid by pumps, while a continuous fluid flow is created by alternating the cycles of receiving and displacing the working chambers of interchangeable two-chamber borehole displacement pumps connected by pipelines of the produced fluid, exhaust and associated gases and a power cable ; for this, the downhole substitution pump for the lower stage of the installation is located in the well, below the static liquid level by 5 - 25 m .; then increase the pressure in the sealed annulus, in where the static liquid level is lowered to a level below the placement of the lower stage of the downhole displacement pump, and due to the difference between the increased pressure and the reduced pressure created by the vacuum compressor unit in the exhaust and associated gas discharge pipe, and in one of the working chambers of the lower stage pump, make fluid intake; and the displacement of the lower stage pump and the pumps of the other stages from the other chamber through the pipeline of the produced fluid to the upper stage pumps is created by the supply of compressed gas from the annulus of the well, while the reception of liquid by the working chambers of the pumps located above is ensured by the displacement of liquid from working chambers below the located pumps.

 Placement of a downhole substitution pump for the lower stage of the installation in the well, below the static liquid level by 5 - 25 m .; and lowering the static liquid level to a level below the placement of the lower stage of the downhole displacement pump, increasing the pressure in the sealed annulus, allows fluid intake due to the difference in the increased pressure and the reduced pressure created by the vacuum compressor unit in the exhaust and associated gas discharge pipe, and in one of the working chambers of the pump lower stage installation;

 The arrival of compressed gas into one chamber from the annulus of the well allows fluid to be displaced from other chambers of the lower stage pump and the pumps of the other stages through the produced fluid pipeline to the upper stage pumps, to use the casing space as a pipeline and compressed gas reservoir at the same time, and to use increased pressure energy , for lifting liquids by substitution pumps connected by a pipeline of produced fluid and a supporting pipeline, which simultaneously serves to drain, working and associated gases to the vacuum compressor unit, for further supply to the annulus of the well, for re-use as a working gas of high pressure.

Placing the replacement pump in the medium of high pressure gas allows it to receive liquid without creating a vacuum, and by combining the flows of exhaust and associated gases, we achieve a significant reduction in the weight of the structure by reducing the number of pipelines. At the same time, the amount of ground equipment used is reduced to one vacuum compressor unit. Due to the repeated use of the exhaust gas by constantly injecting it into the annulus to maintain operating pressure and the absence of associated gas leaks, as well as using a low-voltage 24 V electric current to control the downhole pumps and substitution, the method meets environmental safety requirements

 A method of producing a formation carbonated liquid is as follows.

 When the depth of the formation is up to 50 meters, a single-stage fluid rise is carried out, and at. occurrence over 50 meters, up to 5000 meters - a multi-stage fluid lifting installation based on borehole replacement pumps, shown in the drawings, where Fig.1 is a diagram of a single-stage lifting fluid based on a borehole replacement pump, Fig.2 is a diagram of a multi-stage lifting fluid based on borehole pumps substitutions, FIG. 3 is a schematic diagram of a well pump for substitution; FIG. 4 is a diagram of a bearing flange of a well pump; FIG. 5, 6 and 7 - the operating procedure of well pump replacement.

In FIG. 1, 2, 3, 4, 5, 6, and 7 are shown: casing pipe 1, perforations 2 of the casing pipe, produced fluid 3, downhole displacement pump 4, supporting pipe 5, pipe 6 for raising the produced fluid, receiving pipe 7, cable 8 electrical intermediate, plug 9 of the lower power connector of the lower stage pump, casing flange 10, bearing flange 1 1 of the downhole pump, gasket 12, bearing pipe 13, produced fluid pipe 14, compressed gas pipe 15, vacuum compressor unit 16 for supplying compressed gas , electrical cabinet 17, compressor outlet pipe 18, compressed gas pipe 19, electrical connector 20, electrical connector 21, main pipe 22, central pipe 23, electric air distributor 24, suction pipe 25, discharge pipe 26, lower electrical connector 27, upper electrical connector 28, filter nozzle 29, downhole pump power cable 30, compressor power cable 31, power line 32, compressor inlet 33, connecting pipe 34, excess pipe 35 pressure, overpressure valve 36, associated gas pipe 37, breather 38, pump control section 39, pump main section 40, pump valve section 41, first working chamber 42, second working chamber 43, the float chamber 44 of the first working chamber, the float chamber 45 of the second working chamber, the first double-acting magnetic float valve 46, the second double-acting magnetic float valve 47, the seat 48 of the first working chamber, the seat 49 of the second working chamber, the upper seat 50 of the first working chamber, the upper a saddle 51 of the second working chamber, a reed switch of the level sensor 52 of the first chamber, a reed switch of the level sensor 53 of the second chamber, a suction valve 54 of the first working chamber, a suction valve 55 of the second working chamber, a discharge valve 56 of the first working chamber, pressure valve 57 of the second working chamber, suction channel 58, pressure channel 59, through-wire 60 of the power circuit, power supply wire 61 of the control unit, wire 62 of the control valve, valve 63 control valve, wire 64 reed sensor of the first working chamber, wire 65 reed switch of the second working chamber, hole 66 for exhaust gas, channel 67 for exhaust gas, channel 68 for supplying and discharging working gas to the first working chamber, channel 69 for supplying and discharging the working gas to the second working chamber, the control electronic unit 70, the compressed gas channel 71, the coupling 72, the suspension rod 73 of the receiving pipe, the intermediate wire 74, the compressed gas supply valve 75, the compressed gas filling valve 76, the control gauge valve 77, pressure gauge 78 control, mounting holes 79, branch 80.

 When installing the installation on the basis of well substitution pumps for multi-stage production of carbonated liquid (Fig. 2), all connections are made in the same sequence as when installing a single-stage installation, with the only difference being that after installing the well pump to replace the lower stage, after a certain distance (5 - 50 m.), borehole pumps are installed to replace additional stages, the amount of which depends on the height by which the liquid must be raised, and is determined by the formula:

 n = H / h where n is the number of installation steps

 N - the height by which it is necessary to raise the liquid

h is the step with which borehole replacement pumps are mounted (5 - 50 m.). Consider the implementation of the method with single-stage production of carbonated liquid (figure 1)

 a downhole displacement pump 4 is suspended in a casing 1 of a well by means of a support pipe 5;

 - the receiving pipe 7 with the filter nozzle 29 is connected to a support rod with a sleeve 36 with the lower end of the central pipe 23 of the well pump 4, the sleeve 36 hermetically closes the lower end of the Central pipe 23;

 - the suction pipe 25 is hermetically connected to the receiving pipe 7, while the length of the receiving pipe can be any, and depends only on how deep the liquid must be lifted;

 - a plug 9 is hermetically installed on the lower connector 27;

 - the upper end of the Central pipe 23 is hermetically connected to the carrier pipe 5, and the pipeline of the produced fluid 6 with the discharge pipe 26;

 - to the upper connector 28 connect the cable 8.

When implementing the method, the downhole substitution pump for the lower stage of the installation is located in the well below the static fluid level by 5 - 25 m., While the carrier pipe 5 is hermetically connected to the carrier pipe 13, hermetically assembled on the carrier flange 1 1. The pipe of the produced fluid 6 is connected to the nozzle of the produced fluid 14, which is also hermetically assembled on the carrier flange 1 1. The power cable 8 is connected to the connector 20 located on the carrier flange 1 1. The carrier flange 11 is mounted on the flange of the casing 10, and for echeniya tightness between the gasket 12 is installed and tightened by bolts (not shown). The bearing pipe 13 is connected to the inlet pipe 33 of the compressor 16 by means of a connecting pipe 34. The compressed gas pipe 15 is connected to a valve 75 mounted on the output pipe 18 of the compressor 16 by a pipe 19, and the pipe of the produced fluid 14 is connected to the main pipe 22. The overpressure pipe 35 with an overpressure valve 36 are connected to the associated gas pipeline 37. The power cable of the downhole pump 30, connected at one end to an electrical cabinet 17, is connected to a connector 21 located on the existing flange 1 1 and connected to the connector 20 by means of an intermediate wire 34, hermetically sealed into it. Via cable 31 the compressor 16 is connected to an electrical cabinet 17, which in turn is connected to a power line 32.

 The bearing flange of the installation on the basis of borehole replacement pumps for single-stage or multi-stage lifting of carbonated liquid is structurally no different (Fig. 4) and is an assembly unit consisting of flange 1 1 and nozzles hermetically assembled on it: carrier 13, produced fluid 14, compressed gas 15 with an outlet 80 on it with valve 76, for filling the well with compressed working gas, a control pressure gauge 78, its valve 77 and an overpressure pipe 35 with an overpressure valve 36. On the flange there is a ozheny same electrical connectors 20 and 21 which are interconnected by an intermediate conductor 74.

 The carrier pipe 13 is connected hermetically to the carrier pipe of the well pump and is designed to hold it, at the same time it serves to divert the exhaust and associated gases to the vacuum compressor unit. The nozzle of the produced fluid 14 is connected to the pipeline of the produced fluid of the downhole pump, and serves to pump fluid into the main pipeline. The compressed gas pipe 15 is connected to the outlet pipe of the vacuum compressor unit and is designed to supply compressed gas to the annulus of the well. Branch 80 with valve 76 are designed to fill the well with compressed gas from an external source before starting work, and a control pressure gauge 78 to control the pressure in the well. Overpressure pipe 35 with overpressure valve 36 are designed to remove excess associated gas from the annulus of the well into the associated gas pipeline. The electrical connectors 20 and 21 are interconnected by a hermetically sealed intermediate wire 34 and are designed to transmit power to the downhole pump.

Before turning on the mounted installation in the annulus of the well create an increased pressure of the working (associated) gas to 1, 0 MPa, (Fig. 1 and 2). To do this, from an external source of compressed gas through the valve 76 serves compressed gas into the annulus of the well. Pressure is monitored by a control gauge 78. Valve 75 must be closed when filling the well. Due to the creation in the annulus of increased pressure of the working gas, under the action of which the static liquid level in the well goes down, the downhole substitution pump for the lower stage 4 is above the liquid level. Accordingly, the working gas entering one of the working chambers of the module (Fig. 3) through the breather 38, the compressed gas channel 71, the air distributor 24 and the channels 68 or 69, depending on the position of the air distributor 24, displaces the liquid from the working chamber 42 or 43 Thus, the float valve 46 or 47 is lowered and closes the seats 48 or 49, thereby preventing leakage of compressed gas into the pipeline of the produced fluid 6. The second working chamber at this time remains filled with fluid. The liquid in the pipeline 6 remains at the static level, since the pressure in it does not change and remains low.

 In a multi-stage installation (Fig. 2), compressed gas will also fill one of the working chambers of borehole replacement pumps of all stages. After filling the annulus with compressed gas, valve 75 is opened and the downhole pumping unit is ready for operation.

 Turn on the vacuum compressor unit 16, apply electric current through cable 8 to the borehole displacement pumps 4, and the installation starts to work.

 With a single-stage liquid lifting, the installation for producing carbonated liquid works as follows:

At the time of supplying electric power to control the well pump for substitution in the annulus of the well, there is a working gas under high pressure (Fig. 5). Gas is also located in one of the working chambers, the working chamber 42, and the other working chamber 43 is filled with liquid. The float valve 47, in the upper position, closes the seat 51 and thereby prevents the ingress of liquid into the exhaust gas pipe 5, and the magnet built into it includes a reed switch 53. The pressure in the exhaust gas pipe 5 is low, since the gas is constantly aspirated by vacuum -compressor unit 16. When electric power is supplied via cable 8, the reed switch 53 gives a signal via wire 65 to control unit 70, which generates a command and transmits it via wire 63 to switch the air distributor 24 _.. After switching the pneumatic distributor 24 (Fig. 6), compressed gas begins to enter the chamber 43 from the annulus through the breather 38 through the channels 71 and 69 and displace the liquid into the pipe 6 through the seat 49, the discharge valve 57 and through the channel 59. At the same time, from chamber 42, the compressed gas is removed into the exhaust gas pipe 5 through channels 68 and 67 through the pneumatic distributor 24, as a result of a decrease in pressure, pressure fluid enters the chamber through the seat 48, valve 54 and through the intake channel 58 from the intake pipe 7. When the process of displacing the liquid from the chamber 43 is completed, the float valve 47 closes the seat 49, preventing leakage of compressed gas. At this time, when filling the chamber 42, the float valve 46, floating up, closes the seat 50, at the same time closing the reed switch 52, as a result of which the air distributor 24 switches. After switching the air distributor 24 (Fig. 7), compressed gas enters the chamber 42 and displaces the liquid through the seat 48 and valve 56 into the discharge channel 59 and then into the pipe 6. At this time, compressed gas is removed from the chamber 43 into the exhaust gas pipe 5, and liquid enters the chamber through the seat 49, valve 55 and through the channel 58 from the receiving pipe 7. Prey the liquid being pumped through pipeline 6 rises to the surface, and the exhaust gas through the exhaust gas pipe 5 to the inlet of the vacuum compressor unit 16, which pumps it back into the annulus of the well, thereby maintaining pressure in the annulus. Thus, by continuously alternating between the pium and displacement cycles in the working chambers 42 and 43, the downhole displacement pump creates a continuous flow of fluid in the pipe 6 until the power is turned off.

 In the process of producing soda liquid, associated gas is released into the working gas, and this, in turn, leads to an increase in pressure in the annulus of the well above the working one so that this does not happen, excess associated gas is removed through pipe 35 and an overpressure valve 36 into the associated gas pipeline gas 37.

 With multi-stage lifting of carbonated liquid, the installation on the basis of borehole displacement pumps (Fig. 2) works similarly, with the only difference being that, at certain distances, additional borehole replacement pumps are mounted in it in an amount sufficient to raise the liquid to the surface. Borehole displacement pumps of all stages are identical and interchangeable.

Well substitution pumps of any stage in multi-stage production are designed to receive fluid from the neighboring lower and rise to the neighboring upper and begin to work only when it fills one of the workers 201

 10 cameras, and until that moment they are in standby mode. The principle of operation of all borehole pumps is equivalent to the installation.

 The technical effect is the creation of a method that is easily integrated into the existing oil production system and is electrically safe, easy to operate and maintain, that allows producing carbonated liquids with a high content of mechanical impurities and associated gas from large and shallow depths, and from wells with low debit, including an account of a method for producing formation carbonated liquid, including raising the liquid with pumps, wherein a continuous flow of liquid is created by alternating the cycles of receiving and displacing workers Amer interchangeable dual chamber substitution downhole pump connected by pipelines produced fluid, and removing the exhaust gases and the associated power supply cable; for this, the downhole substitution pump for the lower stage of the installation is located in the well, below the static liquid level by 5 - 25 m .; then increase the pressure in the sealed annulus, in which the static liquid level is lowered to a level lower than the placement of the lower stage of the downhole displacement pump, and due to the difference in the increased pressure and the reduced pressure created by the vacuum compressor unit in the exhaust and associated gas exhaust pipes, and in one of the working chambers of the pump of the lower stage of the installation, liquid is received; and the displacement of the lower stage pump and the pumps of the other stages from the other chamber through the pipeline of the produced fluid to the upper stage pumps is created by the supply of compressed gas from the annulus of the well, while the reception of liquid by the working chambers of the pumps located above is ensured by the displacement of liquid from working chambers below the located pumps.

Claims

FORMULA  A method of producing reservoir carbonated fluid, including raising the fluid with pumps, characterized in that a continuous fluid flow is created by alternating the cycles of receiving and displacing the working chambers of interchangeable two-chamber borehole displacement pumps connected by pipelines of the produced fluid, exhaust and associated gases and a power cable; for this, the downhole substitution pump for the lower stage of the installation is located in the well below the static liquid level by 5 - 25 m .; then increase the pressure in the sealed annulus, in which the static liquid level is lowered to a level lower than the placement of the lower stage of the downhole displacement pump, and due to the difference in the increased pressure and the reduced pressure created by the vacuum compressor unit in the exhaust and associated gas exhaust pipes, and in one of the working chambers of the pump of the lower stage of the installation, liquid is received, and the displacement from the other chamber of the pump of the lower stage and the pumps of the other stages through the pipeline An ode to the produced fluid to the pumps of the upper stages is created due to the arrival of compressed gas from the annulus of the well, while the reception of liquid by the working chambers of the pumps located above is ensured by the displacement of liquid from the working chambers below the pumps.