EP0756065A1 - System zur Kontrolle der Produktion einer Ölbohrung mit Gas-Lift - Google Patents

System zur Kontrolle der Produktion einer Ölbohrung mit Gas-Lift Download PDF

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Publication number
EP0756065A1
EP0756065A1 EP95202038A EP95202038A EP0756065A1 EP 0756065 A1 EP0756065 A1 EP 0756065A1 EP 95202038 A EP95202038 A EP 95202038A EP 95202038 A EP95202038 A EP 95202038A EP 0756065 A1 EP0756065 A1 EP 0756065A1
Authority
EP
European Patent Office
Prior art keywords
production
gas
lift
choke
control module
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP95202038A
Other languages
English (en)
French (fr)
Inventor
Wilhelmus Johannus Godefridus Joseph Der Kinderen
Pieter Koornneef
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shell Internationale Research Maatschappij BV
Original Assignee
Shell Internationale Research Maatschappij BV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shell Internationale Research Maatschappij BV filed Critical Shell Internationale Research Maatschappij BV
Priority to EP95202038A priority Critical patent/EP0756065A1/de
Priority to MYPI96003001A priority patent/MY119607A/en
Priority to PCT/EP1996/003285 priority patent/WO1997004212A1/en
Priority to BR9609763A priority patent/BR9609763A/pt
Priority to CA002226289A priority patent/CA2226289C/en
Priority to EP96927604A priority patent/EP0840836B1/de
Priority to EA199800149A priority patent/EA000484B1/ru
Publication of EP0756065A1 publication Critical patent/EP0756065A1/de
Priority to OA9800009A priority patent/OA10655A/en
Priority to NO19980301A priority patent/NO311450B1/no
Withdrawn legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
    • E21B43/121—Lifting well fluids
    • E21B43/122—Gas lift

Definitions

  • the invention relates to a system for controlling production of crude oil through a production tubing which extends into a gas-lifted oil well whereby lift-gas is injected at a downhole location.
  • the choke is located at the earth surface near the wellhead of the gas-lifted well.
  • the gas injection conduit which is usually formed by the annular space between the production tubing and the well casing, may have a length of several kilometres and may have such a large volume that it is not possible to accurately control the amount of lift-gas which is injected downhole into the production tubing by adjusting the flow of lift-gas that enters the lift-gas injection conduit via the variable choke at the wellhead.
  • Such a variable downhole orifice enables an accurate control of the amount of lift-gas into the well such that always a steady flow of lift-gas is injected and a stable and optimum gas-lift is created.
  • the system according to the invention thereto comprises a variable choke for adjusting the flow of crude oil through said production tubing; and a control module for dynamically controlling the opening of the choke.
  • control module is set to dynamically control the opening of the choke in response to variations in the fluid pressure within the lift-gas conduit.
  • control module usually varies the opening of the choke such that a constant flow of lift-gas is injected into the production tubing and that no slug flow occurs.
  • control module comprises a PID controller which is set to dynamically control the opening of the choke in such a manner that the fluid pressure within said lift-gas injection conduit is minimized and stabilized and which uses the pressure measured by a pressure gauge in the lift-gas injection conduit as input signal and the choke position as output signal.
  • a PID controller is a controller which gives an output signal which is proportional to the input signal, but which also integrates and differentiates the input signal to adjust the characteristics of the output signal.
  • the control module may further comprise a master controller which incorporates a fuzzy logic algorithm to generate for the PID controller a setpoint for the pressure in the lift-gas injection conduit.
  • variable choke and control module are located at the earth surface at a location near the wellhead of the gas-lifted oil production well.
  • the location of the choke and control module at the earth surface allows installation and maintenance thereof outside the well and without interruption of oil production operations which saves significant cost and effort.
  • a gas-lifted crude oil production well comprising a variable choke 1 and a control module CM according to the invention.
  • the choke 1 is mounted in a production tubing 2 which extends from near the bottom of an oil production well 3 through the wellhead 4 towards processing facilities (not shown) at the earth surface 5.
  • Oil is produced via perforations 6 that have been shot into an oil bearing formation.
  • a packer 7 is mounted near the lower end of the production tubing 2 which provides a fluid barrier between the inflow zone 8 at the bottom of the well and the annular space 9 that is formed between the outer surface of the production tubing 2 and the inner surface of a well casing 10.
  • lift-gas is injected via the annulus 9 and a downhole orifice 11 into the production tubing 2.
  • the lift-gas is fed into the annulus via a gas injection conduit 12 and an annular chamber 13 at the wellhead 4.
  • the gas injection conduit 12 is equipped with a choke 14 which serves to adjust the flow of lift-gas.
  • the considerable volume and length of the annular space 9 result in a significant delay between the moment at which the position of the choke 14 is varied and the moment that this results in a variation of the flow of gas that passes through the downhole orifice 11.
  • variable choke 1 and the control module CM serve to avoid that swift variations in the fluid pressure in the production tubing 2 would result in an unstable lift-gas injection regime whereby the lift-gas is injected in slugs via the downhole orifice 11 into the production tubing 2 and the well would start to produce irregular slugs of crude oil and lift-gas.
  • the control module CM is continuously or intermittently fed with data concerning the casing head pressure CHP measured by a pressure gauge at the top of the annular space 9 and the tubing head pressure THP measured by a pressure gauge at the top of the tubing 2. Also data are fed to the control module CM concerning the temperature T of the produced fluid mixture and the flow of lift gas Q lg and of the produced fluid mixture Q prod measured by flowmeters that are mounted in the lift-gas injection conduit 12 and the production tubing 2, respectively. In the embodiment shown the control module CM does not only control the opening of the production choke 1, but also the opening of the lift-gas injection choke 14.
  • the principal operation of the control module CM is that it adjusts the opening of the production choke 1 such that the flow of lift-gas through the downhole orifice 11 remains approximately constant. This is achieved by maintaining a constant differential pressure across the downhole orifice.
  • the pressure downstream of the orifice can be influenced by varying the backpressure at the wellhead, i.e. the tubing head pressure THP. In this way the backpressure exerted by the tubing head pressure THP on the produced fluid mixture is varied such that the backpressure increases in response to a decrease in the measured casing head pressure CHP and vice versa.
  • This variation of the tubing head pressure THP is an adequate measure to accomplish a substantially constant rate of injection of lift-gas at the downhole orifice 11.
  • the control module CM aims to minimize the casing head pressure CHP by variation of the opening of the production choke 1.
  • control module CM is set to obey another rule which dictates that the lower the lift-gas injection rate Q lg is the wider the control margin Cm(t) on the production choke 1 needs to be. Setting this control margin Cm(t) requires some empirical judgement which is incorporated into a fuzzy control unit FCU which is described in more detail with reference to Fig. 2 and Fig. 3.
  • FIG. 2 there is shown a block-scheme which shows the operation of the control module CM.
  • the heart of the control module CM is formed by a conventional PID controller, in the block-scheme referred to as PID, which adjusts the position Cp(t) of the production choke 1 in response to variations of the measured casing head pressure CHP.
  • the flowscheme shows that the casing head pressure CHP is dependant of the tubing head pressure THP, the pressure P res of the fluid in the pores of the reservoir formation RES, and also on the lift-gas injection rate Q lg via the lift-gas choke 14 and the downhole orifice 11.
  • the fuzzy control unit FCU provides a casing head pressure setpoint CHP sp(t) for the PID controller and also adjusts the position of the lift-gas injection choke 14 on the basis of empirical data, represented by arrow 20, which identify classes of suitable positions of the chokes 1 and 11 for various production rates.
  • fuzzy control unit FCU acts as a master controller for the PID controller.
  • the first box at the top indicates that a control cycle starts with a measurement at a certain moment in time (t) of the lift-gas injection rate Q lg (t), the casing head pressure CHP(t) and the actual position Cp(t) of the production choke 1.
  • the next box indicates that on the basis of the measured gas flow rate Q lg (t) the fuzzy control unit calculates the choke margin Cm(t).
  • the fuzzy control unit FCU verifies whether the actual choke position Cp(t) is below the choke margin Cm(t).
  • fuzzy control unit FCU will decrease the setpoint for the casing head pressure CHPsp(t) for the PID controller, whereas if this is not the case said setpoint CHPsp(t) will be increased.
  • the PID controller subsequently verifies whether the measured casing head pressure CHP is lower than the setpoint CHPsp(t) supplied by the fuzzy control unit FCU.
  • the measurement and control cycle is then repeated after a selected interval of time and the same steps of the procedure set out in the flowscheme are taken again.
  • control module according to the invention was tested in a miniaturized well in which water was produced via an 18 metres high riser pipe and in which air was injected as lift-gas via an annulus surrounding the pipe to enhance the flow of water through the riser pipe.
  • the lift-gas injection rate Q lg was 15 m 3 per day and the productivity index PI, simulated with a variable restriction, was 10 m 3 per day per bar.
  • the graph shown in Fig. 4 shows the response of the casing head pressure CHP and fluid production rate Q prod to various settings of the production choke at the top of the riser pipe.
  • the horizontal axis of the graph represents elapsed time, in seconds.
  • the vertical axis contains a scale of 0-100 units which represent both the opening Cp of the production choke (in %), the measured casing head pressure CHP times a factor 50 (in bar) and the fluid production rate Q prod times a factor 10 (in m 3 per day).
  • the graph shows that at this choke setting the production rate Q prod was stable and averaged 1.9 m 3 /day.
  • power for actuating the production choke could be generated by a positive displacement motor or other rotary power generator which utilizes the elevated pressure of the lift-gas within the lift-gas injection conduit as a power source.
  • the inlet of the motor or generator is connected to the lift-gas conduit and the outlet thereof to the oil production tubing.
  • the control system according to the invention is also suitable for use on a well which comprises a plurality of crude oil production tubings which produce crude oil from various locations in a reservoir.
  • a well with multiple completions may produce crude oil either from various inflow regions along a single wellbore or from various inflow regions along different downhole branches.
  • various production tubings may be arranged concentrically within the upper part of the well and lift-gas may be injected at different depths into the production tubings via the annular space formed between the outermost tubing and the well casing.
  • each production tubing is provided with a control system according to the invention which adjusts the opening of a production choke near the top of the production tubing in question in the manner described with reference to the drawings then a stable gas injection and an optimum crude oil production is accomplished in each of the production tubings.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Flow Control (AREA)
  • Control Of Positive-Displacement Air Blowers (AREA)
  • Feeding And Controlling Fuel (AREA)
EP95202038A 1995-07-24 1995-07-24 System zur Kontrolle der Produktion einer Ölbohrung mit Gas-Lift Withdrawn EP0756065A1 (de)

Priority Applications (9)

Application Number Priority Date Filing Date Title
EP95202038A EP0756065A1 (de) 1995-07-24 1995-07-24 System zur Kontrolle der Produktion einer Ölbohrung mit Gas-Lift
MYPI96003001A MY119607A (en) 1995-07-24 1996-07-22 System for controlling production from a gas-lifted oil well
PCT/EP1996/003285 WO1997004212A1 (en) 1995-07-24 1996-07-23 System for controlling production from a gas-lifted oil well
BR9609763A BR9609763A (pt) 1995-07-24 1996-07-23 Sistema para controle de produção de óleo cru
CA002226289A CA2226289C (en) 1995-07-24 1996-07-23 System for controlling production from a gas-lifted oil well
EP96927604A EP0840836B1 (de) 1995-07-24 1996-07-23 System zur kontrolle der produktion einer ölbohrung mit gas-lift
EA199800149A EA000484B1 (ru) 1995-07-24 1996-07-23 Система управления газлифтной добычей нефти из нефтяной скважины
OA9800009A OA10655A (en) 1995-07-24 1998-01-23 System for controlling production from a gas-lifted oil well
NO19980301A NO311450B1 (no) 1995-07-24 1998-01-23 System for styring av produksjon av råolje fra en gasslöftet oljebrönn

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP95202038A EP0756065A1 (de) 1995-07-24 1995-07-24 System zur Kontrolle der Produktion einer Ölbohrung mit Gas-Lift

Publications (1)

Publication Number Publication Date
EP0756065A1 true EP0756065A1 (de) 1997-01-29

Family

ID=8220529

Family Applications (2)

Application Number Title Priority Date Filing Date
EP95202038A Withdrawn EP0756065A1 (de) 1995-07-24 1995-07-24 System zur Kontrolle der Produktion einer Ölbohrung mit Gas-Lift
EP96927604A Expired - Lifetime EP0840836B1 (de) 1995-07-24 1996-07-23 System zur kontrolle der produktion einer ölbohrung mit gas-lift

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP96927604A Expired - Lifetime EP0840836B1 (de) 1995-07-24 1996-07-23 System zur kontrolle der produktion einer ölbohrung mit gas-lift

Country Status (7)

Country Link
EP (2) EP0756065A1 (de)
CA (1) CA2226289C (de)
EA (1) EA000484B1 (de)
MY (1) MY119607A (de)
NO (1) NO311450B1 (de)
OA (1) OA10655A (de)
WO (1) WO1997004212A1 (de)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2783559A1 (fr) * 1998-09-21 2000-03-24 Elf Exploration Prod Methode de conduite d'un dispositif de transport d'hydrocarbures entre des moyens de production et une unite de traitement
FR2783557A1 (fr) 1998-09-21 2000-03-24 Elf Exploration Prod Methode de conduite d'un puits de production d'hydrocarbures active par injection de gaz
EP1028227A1 (de) * 1999-02-10 2000-08-16 Intevep SA Verfahren und Vorrichtung zur Optimierung der Produktion von Gasliftbohrungen
FR2822191A1 (fr) * 2001-03-19 2002-09-20 Inst Francais Du Petrole Methode et dispositif pour neutraliser par injection controlee de gaz, la formation de bouchons de liquide au pied d'un riser se raccordant a une conduite d'acheminement de fluides polyphasiques
US7278481B2 (en) 2001-10-01 2007-10-09 Shell Oil Company Method and system for producing an oil and gas mixture through a well
FR3011874A1 (fr) * 2013-10-14 2015-04-17 Total Sa Installation de production d’hydrocarbures, procede de production et procede de mise a niveau
US9234410B2 (en) 2009-02-13 2016-01-12 Total S.A. Method for controlling a hydrocarbons production installation
WO2016084058A1 (en) 2014-11-30 2016-06-02 Abb Technology Ltd. A method and a control system for optimizing production of a hydrocarbon well
FR3034232A1 (de) * 2015-03-25 2016-09-30 Landmark Graphics Corp
US11613972B2 (en) 2017-09-15 2023-03-28 IntelliGas CSM Services Limited System and method for low pressure gas lift artificial lift

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO982973D0 (no) * 1998-06-26 1998-06-26 Abb Research Ltd Anordning ved oljebr°nn
NO313677B1 (no) 2000-12-06 2005-10-24 Abb Research Ltd Slug kontrollering
BRPI0519164B1 (pt) * 2004-12-21 2016-11-22 Shell Int Research método para controlar o fluxo de um fluido multifásico a partir de um poço e poço estendendo-se para dentro de uma formação de sub-superfície
GB2429797B (en) * 2005-08-31 2010-09-08 Genesis Oil And Gas Consultant Pipeline control system
EP3055498B1 (de) * 2013-10-11 2019-05-01 Raise Production, Inc. Übergangsventilsystem und verfahren zur gaserzeugung

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2298834A (en) * 1940-05-24 1942-10-13 Standard Oil Dev Co Means for producing oil wells
WO1988000277A1 (en) * 1986-07-07 1988-01-14 B.W.N. Vortoil Pty. Ltd. Method for startup of production in an oil well
GB2252797A (en) * 1991-02-14 1992-08-19 Elf Aquitaine Controlling production flow of an oil well 36
US5172717A (en) * 1989-12-27 1992-12-22 Otis Engineering Corporation Well control system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2298834A (en) * 1940-05-24 1942-10-13 Standard Oil Dev Co Means for producing oil wells
WO1988000277A1 (en) * 1986-07-07 1988-01-14 B.W.N. Vortoil Pty. Ltd. Method for startup of production in an oil well
US5172717A (en) * 1989-12-27 1992-12-22 Otis Engineering Corporation Well control system
GB2252797A (en) * 1991-02-14 1992-08-19 Elf Aquitaine Controlling production flow of an oil well 36

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ADJUNTA ET AL.: "Wellhead monitors automate Lake Maracaibo gas lift", OIL & GAS JOURNAL, 28 November 1994 (1994-11-28), pages 64 - 67, XP002017975 *

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2783559A1 (fr) * 1998-09-21 2000-03-24 Elf Exploration Prod Methode de conduite d'un dispositif de transport d'hydrocarbures entre des moyens de production et une unite de traitement
FR2783557A1 (fr) 1998-09-21 2000-03-24 Elf Exploration Prod Methode de conduite d'un puits de production d'hydrocarbures active par injection de gaz
GB2342109A (en) * 1998-09-21 2000-04-05 Elf Exploration Prod Method for controlling a hydrocarbons production well activated by injection of gas
US6286602B1 (en) 1998-09-21 2001-09-11 Elf Exploration Production Method for controlling a device for transporting hydrocarbons between production means and a treatment plant
US6293341B1 (en) 1998-09-21 2001-09-25 Elf Exploration Production Method of controlling a hydrocarbons production well activated by injection of gas
GB2342109B (en) * 1998-09-21 2002-09-04 Elf Exploration Prod Method for controlling a hydrocarbons production well activated by injection of gas
EP1028227A1 (de) * 1999-02-10 2000-08-16 Intevep SA Verfahren und Vorrichtung zur Optimierung der Produktion von Gasliftbohrungen
US6182756B1 (en) 1999-02-10 2001-02-06 Intevep, S.A. Method and apparatus for optimizing production from a gas lift well
FR2822191A1 (fr) * 2001-03-19 2002-09-20 Inst Francais Du Petrole Methode et dispositif pour neutraliser par injection controlee de gaz, la formation de bouchons de liquide au pied d'un riser se raccordant a une conduite d'acheminement de fluides polyphasiques
US7103521B2 (en) 2001-03-19 2006-09-05 Institut Francais Du Petrole Method and device for neutralizing, by controlled gas injection, the formation of liquid slugs at the foot of a riser connected to a multiphase fluid transport pipe
US7278481B2 (en) 2001-10-01 2007-10-09 Shell Oil Company Method and system for producing an oil and gas mixture through a well
US9234410B2 (en) 2009-02-13 2016-01-12 Total S.A. Method for controlling a hydrocarbons production installation
FR3011874A1 (fr) * 2013-10-14 2015-04-17 Total Sa Installation de production d’hydrocarbures, procede de production et procede de mise a niveau
WO2015055645A1 (fr) 2013-10-14 2015-04-23 Total Sa Installation de production d'hydrocarbures, procede de production et procede de mise a niveau
US10030488B2 (en) 2013-10-14 2018-07-24 Total Sa Hydrocarbon production facility, production method and upgrade method
WO2016084058A1 (en) 2014-11-30 2016-06-02 Abb Technology Ltd. A method and a control system for optimizing production of a hydrocarbon well
US10494906B2 (en) 2014-11-30 2019-12-03 Abb Schweiz Ag Method and a control system for optimizing production of a hydrocarbon well
US10876383B2 (en) 2014-11-30 2020-12-29 Abb Schweiz Ag Method and system for maximizing production of a well with a gas assisted plunger lift
FR3034232A1 (de) * 2015-03-25 2016-09-30 Landmark Graphics Corp
US11613972B2 (en) 2017-09-15 2023-03-28 IntelliGas CSM Services Limited System and method for low pressure gas lift artificial lift

Also Published As

Publication number Publication date
NO980301L (no) 1998-03-24
EP0840836B1 (de) 2000-10-11
WO1997004212A1 (en) 1997-02-06
NO311450B1 (no) 2001-11-26
EA000484B1 (ru) 1999-08-26
NO980301D0 (no) 1998-01-23
MY119607A (en) 2005-06-30
CA2226289C (en) 2008-01-15
EA199800149A1 (ru) 1998-08-27
OA10655A (en) 2002-09-19
CA2226289A1 (en) 1997-02-06
EP0840836A1 (de) 1998-05-13

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