WO2014186823A1 - Appareil d'injection d'oxydant et d'eau - Google Patents

Appareil d'injection d'oxydant et d'eau Download PDF

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Publication number
WO2014186823A1
WO2014186823A1 PCT/AU2014/000526 AU2014000526W WO2014186823A1 WO 2014186823 A1 WO2014186823 A1 WO 2014186823A1 AU 2014000526 W AU2014000526 W AU 2014000526W WO 2014186823 A1 WO2014186823 A1 WO 2014186823A1
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WO
WIPO (PCT)
Prior art keywords
oxidant
casing
conduit
water
oxidant conduit
Prior art date
Application number
PCT/AU2014/000526
Other languages
English (en)
Inventor
Ernest DU TOIT
Original Assignee
Linc Energy Ltd
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
Priority claimed from AU2013901848A external-priority patent/AU2013901848A0/en
Application filed by Linc Energy Ltd filed Critical Linc Energy Ltd
Publication of WO2014186823A1 publication Critical patent/WO2014186823A1/fr
Priority to AU2015101707A priority Critical patent/AU2015101707A4/en

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP 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
    • E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
    • E21B43/24—Enhanced recovery methods for obtaining hydrocarbons using heat, e.g. steam injection
    • E21B43/243—Combustion in situ
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP 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
    • E21B43/295—Gasification of minerals, e.g. for producing mixtures of combustible gases

Definitions

  • This invention relates to underground coal gasification (UCG).
  • UCG underground coal gasification
  • a device and method for injecting an oxidant and water into a coal seam are disclosed.
  • Underground coal gasification is a process by which product gas is produced from a coal seam by combusting and gasifying the coal in situ in the presence of an oxidant.
  • the product gas is typically referred to as synthesis gas or syngas and can be used as a feedstock for various applications, including clean fuels production, chemical production and electricity generation.
  • Wells are drilled into the coal seam to allow for oxidant injection and product gas extraction.
  • the wells are linked or extended to form a substantially horizontal wellbore (also referred to as an in-seam well channel) to facilitate oxidant injection, cavity development and product gas flow.
  • the well allowing the injection of oxidant is called an injection well.
  • the well from which product gas emerges is called a production well.
  • Both horizontal and vertical well regions can be used for injection and production.
  • Underground coal gasification may also utilise one or more vertical wells (service wells) located between the injection and production wells.
  • a coal seam having injection and production wells with a substantially horizontal wellbore linking the two is typically referred to as an underground coal gasifier.
  • the gasifier will have a combustion zone within which coal is combusted in the presence of an oxidant, a gasification zone located downstream of the combustion zone in which coal is gasified and partially oxidized to produce product gas, and a downstream pyrolysis zone in which pyrolysis of coal occurs.
  • Hot product gas flows downstream from the gasification zone and exits the ground from a well head of the production well.
  • a gasifier (gasification) cavity within the coal seam develops and grows in size.
  • the product gas (raw syngas) generated by UCG typically includes syngas as well as other components, and the constituency will depend on various factors including the type of oxidant used for UCG (air or other oxidant, such as oxygen or oxygen-enriched air), water presence (both ground water and exogenous water), coal quality, and UCG operating temperature and pressure.
  • the invention provides a device for supplying an oxidant and water to an underground coal gasifier, including: a) an oxidant conduit, the oxidant conduit having at least one opening at a downhole end for injecting oxidant into the underground coal gasifier and an uphole end adapted for fluidly connecting the conduit to coiled tubing and b) a casing seal adapted for sealing a casing annulus between the oxidant conduit and a casing of a cased wellbore, the casing seal having one or more channels for injecting water into the underground coal gasifier.
  • the casing seal includes a plurality of channels for injecting water into the underground coal gasifier and the plurality of channels are adapted to direct the flow of the injected water toward the downhole end of the oxidant conduit and/or toward the casing of the cased wellbore.
  • the one or more channels for injecting water into the underground coal gasifier terminate in a water injection nozzle.
  • the device further includes an oxidant injection nozzle connected to the downhole end of the oxidant conduit.
  • the device further includes one or more sensors for sensing and reporting conditions in the oxidant conduit, adjacent the oxidant conduit, and/or the wellbore.
  • the device further includes a positioning system having coiled tubing connected to the uphole end of the oxidant conduit and extendible within the cased wellbore to position the device at a desired location within the wellbore.
  • the invention provides a device for supplying an oxidant and water to an underground coal gasifier accessed by a cased wellbore, including: a) an oxidant conduit, the oxidant conduit having at least one opening at a downhole end for injecting oxidant into the underground coal gasifier, an oxidant injection nozzle connected to the downhole end of the oxidant conduit, and an uphole end adapted for fluidly connecting the conduit to coiled tubing, and b) a casing seal adapted for sealing a casing annulus between the oxidant conduit and a casing of the cased wellbore, the casing seal having a plurality of channels for injecting water into the underground coal gasifier, wherein the plurality of channels for injecting water into the underground coal gasifier are adapted to direct the flow of the injected water toward the downhole end of the oxidant conduit and/or toward the casing of the cased wellbore.
  • the device further includes a positioning system having coiled tubing connected to the uphole end of the oxidant conduit and extendible within the cased wellbore to position the device at a desired location within the wellbore.
  • the invention provides a method of underground coal gasification in a coal seam provided with an injection well, an ignition well, a production well, and a substantially horizontal wellbore linking the injection well and the production well, including the steps of: a) inserting a casing into the wellbore, b) inserting a device for supplying an oxidant and water to an underground coal gasifier as set forth herein through the injection well, wherein the device extends within the cased wellbore linking the injection well and the production well, c) igniting the coal seam using an ignition tool located within the ignition well, d) providing oxidant and water to the device for injection into the coal seam, and e) withdrawing product gas from the production well.
  • Figure 1 a perspective view of a device for supplying an oxidant and water to an underground coal gasifier according to an embodiment of the present invention.
  • Figure 2 is an end view of the device illustrated in Figure 1.
  • Figure 3 is a cutaway view of a section of a cased wellbore of an underground coal gasifier including the device illustrated in Figure 1.
  • the present invention relates to a device and method for injecting an oxidant and water into a coal seam of an underground coal gasifier.
  • the invention includes a device for supplying an oxidant and water to an underground coal gasifier (also referred to as an "oxidant/water injection tool"), including: a) an oxidant conduit, the oxidant conduit having at least one opening at a downhole end for injecting oxidant into the underground coal gasifier and an uphole end adapted for fluidly connecting the conduit to coiled tubing and b) a casing seal adapted for sealing a casing annulus between the oxidant conduit and a casing of a cased wellbore, the casing seal having one or more channels for injecting water into the underground coal gasifier.
  • the oxidant conduit can be of any suitable size, shape and construction, and can be made of any suitable material or materials.
  • the oxidant conduit can be manufactured in shapes and sizes to suit the specific application.
  • the oxidant conduit has a round cross-section to provide an annular passage, although other cross-section shapes are possible, as will be understood by one of ordinary skill in the art.
  • the oxidant conduit can be of unitary construction or can include two or more connectable segments/pieces. Where the oxidant conduit includes multiple connectable segments/pieces, these segments/pieces can be screwed and/or welded together to form a complete conduit. For example, the ends of each conduit segment can be threaded, and the full-length oxidant conduit can include one or more threaded collars for connecting the ends of adjacent segments together.
  • adjacent conduit segments can be welded together to form a full-length oxidant conduit.
  • the oxidant conduit can have any suitable outside diameter and length.
  • the oxidant conduit can have an outside diameter of about two to four inches, including, for example, 2.25 inches, 2.50 inches, 2.75 inches, 3.00 inches, 3.25 inches, 3.50 inches, and 3.75 inches.
  • the oxidant conduit has an outside diameter of about 2.00 inches.
  • the outside diameter of the oxidant conduit will not exceed the inside diameter of a cased wellbore into which the oxidant/water injection tool is to be inserted.
  • the oxidant conduit (including segments and threaded collars) can be made of material that is resistant to high temperatures and corrosion, and/or undergoes controlled expansion at elevated temperatures, such as those found in an active underground coal gasifier (e.g., in the range of 400 to 1 ,200 °C).
  • Exemplary metal, metal alloys, and ceramics suitable for the oxidant conduit include, but are not limited to, stainless steel (and alloys thereof), chromium-nickel alloys (including those containing silicon, cobalt, tungsten, molybdenum, and microalloying elements such as nitrogen, and rare earth metals such as cesium),the Inconel ® (predominantly nickel-chromium alloys), Monel ® (predominantly nickel-copper alloys), and Hastelloy ® (predominantly nickel-containing alloys) families of high-performance alloys, zirconia toughened alumina, yttrium stabilised zirconia, zirconia di-oxide, and silicon carbide.
  • stainless steel and alloys thereof
  • chromium-nickel alloys including those containing silicon, cobalt, tungsten, molybdenum, and microalloying elements such as nitrogen, and rare earth metals such as cesium
  • the Inconel ® predomin
  • the oxidant conduit can be coated (e.g., via plasma coating) with a protective coating, including, for example, ceramic coatings, zirconia (zirconium oxide) coatings, alumina-zirconia coatings, and carbon composite coatings.
  • a protective coating including, for example, ceramic coatings, zirconia (zirconium oxide) coatings, alumina-zirconia coatings, and carbon composite coatings.
  • the oxidant conduit includes a downhole end having at least one opening for injecting oxidant into an underground coal gasifier and an opposing, uphole end configured to receive oxidant from above ground.
  • the downhole end of the oxidant conduit can be tapered or otherwise shaped so as to reduce resistance when moving the oxidant/water injection tool to its intended location within a cased wellbore within a coal seam.
  • the uphole end of the oxidant conduit can be of any suitable size and shape, and is preferably adapted for fluidly connecting the conduit to coiled tubing.
  • An oxidant is fed through the uphole end of the oxidant conduit, exiting through the downhole end having at least one opening for injecting oxidant into an underground coal gasifier. Additionally, an electrical cable, sensor or other component can extend through the uphole end of the oxidant conduit.
  • the oxidant/water injection tool is positionable and retractable. Positioning and retracting of the tool can be achieved utilising coiled tubing connected to the oxidant conduit and extendible within a cased wellbore to position the tool at a desired location within the wellbore/retract the tool within the wellbore. Accordingly, in some embodiments, the oxidant/water injection tool includes a coiled tubing adapter connected to the uphole end of the oxidant conduit.
  • the at least one opening for injecting oxidant into an underground coal gasifier at the downhole end of the oxidant conduit can be of any suitable size and shape for distributing oxidant into the cased wellbore of the underground coal gasifier.
  • an oxidant injection nozzle is connected to the downhole end of the oxidant conduit.
  • the injection nozzle connected to the downhole end of the oxidant conduit can be straight, bent, or side-ported (including spaced side apertures).
  • the oxidant injection nozzle can be made of material that is resistant to high temperatures and corrosion, and/or is coated with a protective coating, as discussed herein.
  • Selection of the orientation of the oxidant injection nozzle connected to the downhole end of the oxidant conduit and the oxidant exit velocity can be used to direct underground gasifier cavity growth in either horizontal or vertical directions. That is, gasifier cavity growth in a coal seam can be tailored by adjusting the axial and/or radial distribution of the injection nozzle (including spaced side apertures), as well as the oxidant exit velocity. This can be used to promote lateral growth of the cavity to increase resource recovery, particularly in thin coal seams.
  • the oxidant conduit further includes a nonreturn/check valve (e.g., ball and spring, spring loaded flapper valve, or the like) fitted within the conduit.
  • a check valve can prevent oxidant and/or product gas reverse flow in the oxidant conduit.
  • More than one check valve can be included.
  • dual check valves can be included in the oxidant conduit.
  • the casing seal (or sleeve/collar) adapted for sealing a casing annulus between the oxidant conduit and a casing of a cased wellbore can be of any suitable size, shape and construction, and can be made of any suitable material or materials.
  • underground coal gasifier limit the use of traditional rubber-based elastomeric sealing materials in the construction of the casing seal.
  • sealing and/or engagement means employing a flexible metal seal rather than an elastomer as their sealing element to contact the oxidant conduit/casing and form a tight, durable seal that is retractable and withstands the HP/HT and/or corrosive-conditions in an underground coal gasifier are preferred.
  • Such flexible metal seals are configured to seal, grip or otherwise secure the annular space between the oxidant conduit and the casing of the cased wellbore.
  • Metal-to metal seals and sealing systems are available from a variety of suppliers, including, for example, Baker Oil Tools (Houston, Texas, USA) and Caledyne Ltd (Aberdeen, Scotland).
  • any friction fit sealing device/system (including a collar or a sleeve) can be used in the
  • the sealing device/system is capable of maintaining a sealed casing annulus between the oxidant conduit and the casing of a cased wellbore, is retractable, and withstands the HP/HT and/or corrosive-conditions in the gasifier.
  • the one or more channels in the casing seal for injecting water into an underground coal gasifier can include a plurality of channels for injecting water into the underground coal gasifier. Additionally, the channels can be adapted to direct the flow of the injected water toward the downhole end of the oxidant conduit and/or toward the casing of the cased wellbore.
  • the one or more channels for injecting water into the underground coal gasifier terminate in a water injection nozzle.
  • the water injection nozzle can be straight, bent, or side-ported (including spaced side apertures), and can be made of material that is resistant to high temperatures and corrosion, and/or is coated with a protective coating, as discussed herein.
  • the water source can include a fluid delivery system to deliver the water, and this can be of any suitable size, shape, and construction.
  • the fluid delivery system includes an existing cased well (e.g., an injection well or service well) for conveying the water to the casing seal of the oxidant/water injection tool.
  • the delivery system can further include a circulation pump and fluid reservoir connected to a well head/above-ground portion of the well for pumping the water into the well.
  • the oxidant/water injection tool and/or the fluid delivery system can include at least one thermocouple electrically connected to a computer-operable valve for regulating the injection rate and quantity of water according to the temperature reading.
  • the downhole end of the oxidant conduit can extend a variable length beyond the casing seal, or can be substantially flush with the casing seal.
  • the distance that the downhole end of the oxidant conduit extends beyond the casing seal is a design variable based on, inter alia, the composition/thickness of casing inserted into a wellbore and thus how far forward burn back of the casing needs to be controlled.
  • the casing will naturally burn back as a gasifier cavity develops within a coal seam in the vicinity of oxidant injection.
  • the oxidant/water injection tool can include a detachable cap or plug (e.g., blow-out plug) covering the downhole end of the oxidant conduit, which can be detached from the conduit prior to oxidant injection.
  • the cap or plug can be bull nose, long nose, or conical in shape. Detachment can be achieved in any suitable way. For example, an increase in gas pressure due to oxidant flow through the oxidant conduit can be used to detach the cap or plug.
  • the cap or plug can friction fit to the downhole end of the oxidant conduit. If in the form of a plug, a stem of the plug can friction fit to the conduit using an O-ring that extends around the stem of the plug.
  • the oxidant/water injection tool further includes one or more sensors for sensing and reporting conditions in the oxidant conduit, adjacent the oxidant conduit, the wellbore, and/or the coal seam.
  • Any suitable type of sensor can be used.
  • the sensor can be a thermocouple for sensing the temperature, a gas sensor for sensing the nature of the product gas, a pressure sensor for sensing pressure, an optical sensor for viewing the wellbore, or a position sensor for reporting the location of the oxidant/water injection tool within the wellbore.
  • the oxidant/water injection tool can include one or more
  • thermocouples so that temperature information/data can be collected from the tool. This temperature information/data can be used to control the operating parameters of the oxidant/water injection tool, including oxidant injection rate and quantity, and water injection rate and quantity.
  • the one or more sensors can be located within the oxidant/water injection tool (e.g., within the oxidant conduit) and/or attached to an external surface of the tool, including the oxidant conduit.
  • An electrical cable of the one or more sensors can extend within the coiled tubing and internally or externally of the oxidant conduit of the oxidant/water injection tool.
  • the oxidant/water injection tool can include a controller operable to control the release/injection of oxidant/water.
  • the controller can include a pipe manifold in fluid communication with the coiled tubing and oxidant and water sources.
  • the controller can be operable remotely from the oxidant/water injection tool.
  • the controller can include trim, non-return, and isolation valves, flow measuring devices, and pressure relief devices. Such operating devices allow for injection rate
  • Oxidant/water injection rate and quantity can be adjusted using flow controlling devices, such devices being either pneumatically actuated, manually choked, quarter-turn types, or electrically actuated.
  • the controller can include pressure safety devices, filtration devices, and flow metering devices, in addition to isolation valves. Control logic can allow the oxidant/water to flow as per the required settings.
  • the source of oxidant and water can be connected to a pipe manifold of the controller and further to the coiled tubing and a well head of an injection well.
  • a power supply e.g., generator
  • a power supply can be electrically connected to the controller and further to an electrical cable and sensor cable extending through the coiled tubing.
  • the invention includes a device for supplying an oxidant and water to an underground coal gasifier accessed by a cased wellbore, including: a) an oxidant conduit, the oxidant conduit having at least one opening at a downhole end for injecting oxidant into the underground coal gasifier, an oxidant injection nozzle connected to the downhole end of the oxidant conduit, and an uphole end adapted for fluidly connecting the conduit to coiled tubing, and b) a casing seal adapted for sealing a casing annulus between the oxidant conduit and a casing of the cased wellbore, the casing seal having a plurality of channels for injecting water into the underground coal gasifier, wherein the plurality of channels for injecting water into the underground coal gasifier are adapted to direct the flow of the injected water toward the downhole end of the oxidant conduit and/or toward the casing of the cased wellbore.
  • the invention includes a method of underground coal gasification in a coal seam provided with an injection well, an ignition well, a production well, and a substantially horizontal wellbore linking the injection well and the production well, including the steps of: a) inserting a casing into the wellbore, b) inserting a device for supplying an oxidant and water to an underground coal gasifier as set forth herein through the injection well, wherein the device extends within the cased wellbore linking the injection well and the production well, c) igniting the coal seam using an ignition tool located within the ignition well, d) providing oxidant and water to the device for injection into the coal seam, and e) withdrawing product gas from the production well.
  • the casing extends from adjacent a heel of the injection well to adjacent a heel of the production well.
  • the size, shape and construction of the casing is selected to ensure that it can be installed into a wellbore of an underground coal gasifier and remains intact during service (i.e., it keeps the wellbore open).
  • the casing is strong enough to be inserted into the wellbore using traditional drilling service equipment, as will be known to one of ordinary skill in the art.
  • the casing can be of any suitable size, shape and construction and can be made of any suitable material or materials.
  • Exemplary materials suitable for the casing include, but are not limited to, metal (such as carbon steel, stainless steel, copper, or aluminium), fibreglass, carbon fibre, plastic, and combinations thereof.
  • the casing can be of any suitable diameter and length. Typically, the casing will have an outside diameter of anywhere between about 5 to 10 inches, more preferably about 5 to 8 inches, and even more preferably about 5.5 to 7 inches.
  • the casing can be of unitary construction or can include a plurality of connectable units (i.e., segments).
  • the casing or segments can be of any suitable length, including, metres, tens of metres, hundreds of metres, and kilometres.
  • casing segments can be connected together to form a full-length casing being tens of metres long, hundreds of metres long, or even several kilometres in length, depending on the length of the wellbore.
  • Each casing segment can be, for example, about 1 to 10 metres in length, including about 3, 5, 6, 7, or 9 metres in length.
  • the casing segments can be connected together in any suitable way.
  • the ends of each segment can be threaded, and the full-length casing can include one or more threaded collars for connecting the ends of adjacent casing segments together.
  • the casing (including segments thereof) can be manufactured in shapes and sizes to suit the specific application.
  • the casing has a round cross- section to provide an annular passage, although other cross-section shapes are possible, as will be understood by one of ordinary skill in the art.
  • Inserting (and positioning) the oxidant/water injection tool within the cased wellbore can be achieved utilising coiled tubing as discussed herein.
  • the oxidant conduit of the oxidant/water injection tool can be connected to the coiled tubing in any suitable way.
  • the oxidant conduit is connected to the coiled tubing in a fluid-tight manner.
  • the oxidant conduit can be releasably connected or
  • the oxidant conduit is connected to an end of the coiled tubing by way of a quick connector (such as grapple, torque thru, dimple, etc.), screw thread, or weld.
  • a quick connector such as grapple, torque thru, dimple, etc.
  • the coiled tubing can be of any suitable size, shape and construction and can be made of any suitable material or materials. More particularly, the coiled tubing can be of any suitable length and diameter. Preferably, the coiled tubing is made of metal, such as stainless steel, carbon steel, or copper. The coiled tubing can be of unitary construction or can include two or more connectable tube pieces. A preferred outside diameter for the coiled tubing is 1.75 to 3.5 inches. The coiled tubing can be maintained on a spool from which the coiled tubing is unspooled.
  • the step of igniting the coal seam preferably includes using an ignition tool, whereby an ignition tool that includes ignition means is inserted into the coal seam via an ignition well. Once introduced into the coal seam, the ignition tool is used to ignite the coal seam and establish a combustion zone.
  • Positioning of the ignition tool can be achieved utilising coiled tubing connected to the tool and extendible within the ignition well to position the tool at a desired location within the coal seam.
  • the ignition tool can ignite the coal seam in any suitable way.
  • the ignition tool can directly ignite the coal seam or ignite a combustible fuel (i.e., an ignition fuel) supplied to the ignition well (e.g., supplied as a gas, liquid, or solid).
  • a combustible fuel i.e., an ignition fuel
  • Suitable ignition fuels include, but are not limited to, hydrocarbon gases, for example, methane, propane, butane, and mixtures thereof.
  • ignition means includes an electrical spark generator (e.g., a spark plug) or an electrical heat resistor (e.g., a glow plug) and a power supply for generating the spark/electrifying the resistor.
  • Ignition means further include at least one type of ignition chemical.
  • the ignition chemical can be a pyrophoric substance (e.g., a liquid, such as triethylboron (TEB), a gas, such as silane, a solid, such as phosphorus or an alkali metal), a pyrophoric substance and a hydrocarbon mixture, such as TEB vaporised in methane, or a pyrophoric substance and an inert gas, such as TEB and nitrogen.
  • a pyrophoric substance e.g., a liquid, such as triethylboron (TEB), a gas, such as silane, a solid, such as phosphorus or an alkali metal
  • a pyrophoric substance and a hydrocarbon mixture such as TEB vaporised in methane
  • an inert gas such as TEB and nitrogen.
  • the hydrocarbon or inert gas flow can help transport/vaporise the pyrophoric substance to the ignition tool.
  • oxidant is injected into the substantially horizontal wellbore via the oxidant/water injection tool to fuel/maintain combustion of the coal seam. Additionally, water is injected as needed to regulate downhole well/wellbore temperatures in the vicinity of the oxidant/water injection tool and other downhole tools, control casing burn-back, and optimise resource recovery in the coal seam.
  • the oxidant is preferably a gas such as air (approximately 20% oxygen), oxygen-enriched air (greater than 20% oxygen), or a gas/gas mixture (e.g., CO2 and/or nitrogen in any desired ratio) enriched with oxygen (greater than 20% oxygen), or, most preferably, substantially pure oxygen.
  • the oxidant source can include an air compressor, a tank/cylinder of compressed air or oxygen, an air separation unit, or a tank/cylinder of liquid oxygen, for example.
  • the source of the oxidant can be connected directly or indirectly to coiled tubing associated with the oxidant conduit in a fluid-tight manner, for introduction of the oxidant into the cased wellbore via the oxidant conduit of the oxidant/water injection tool.
  • oxidant can be injected at any suitable injection rate and quantity.
  • the injection rate can be chosen with respect to various design criteria, including ensuring that the rate of casing burn- back and/or the quality and/or composition of the product gas (e.g., the calorific value and/or the H 2 to CO ratio) emerging from the production well are as desired.
  • the product gas e.g., the calorific value and/or the H 2 to CO ratio
  • One of ordinary skill in the art will be able to formulate the rate and quantity of oxidant injection necessary to achieve desired outcomes.
  • water injection assists in maintaining downhole well/wellbore temperatures in the vicinity of the oxidant/water injection tool within a desired range, to improve mechanical integrity and/or reliability of the tool (and other downhole tools), and controlling casing burn- back.
  • water injection can be used to lower the temperature in a region of an underground coal gasifier such that less damage is caused to mechanical components used in UCG. Additionally, water injection can be used to alter the chemical composition of the product gas stream prior to it reaching or leaving the production well.
  • Water for injection can be obtained from a naturally occurring water source, such as surface water or ground water.
  • the water can be either fresh water or brine.
  • the water can be treated water, such as demineralised water or raw water separated from UCG product gas.
  • water can be injected at any suitable injection rate and quantity.
  • the injection rate can be chosen with respect to various design criteria, including ensuring that injection of water via the oxidant/water injection tool is sufficient to maintain downhole well/wellbore temperatures within a desired range.
  • One of ordinary skill in the art will be able to formulate the rate and quantity of water injection necessary to achieve desired outcomes.
  • the oxidant/water injection tool is positionable and retractable. In order to continue the UCG process through a coal seam, it will be necessary to reposition the oxidant/water injection tool periodically to progress the combustion zone along the coal seam and provide optimum resource recovery of the underground coal resource.
  • the coiled tubing and oxidant/water injection tool can be drawn along the cased wellbore that extends through the coal seam.
  • a preferred method is utilising the controlled retracting injection point (CRIP) concept, as will be understood by one of ordinary skill in the art.
  • FIG. 1 there is generally depicted a device 10 for supplying an oxidant and water to an underground coal gasifier according to an embodiment of the present invention.
  • the oxidant/water injection tool 10 has a 2.00" outside diameter oxidant conduit 12 that includes a downhole end having an opening 15 and an uphole end 17 adapted for fluidly connecting the oxidant conduit 12 to coiled tubing, and a casing seal 20 adapted for sealing a casing annulus between the oxidant conduit 12 and a casing of a cased wellbore.
  • One or more circumferential stop shoulders (not shown) at the downhole end of the oxidant conduit 12 in combination with a compression ring (not shown) can be used to secure the casing seal 20 to the oxidant conduit 12 and facilitate quick adjustments of the relative position of the casing seal 20 along the length of the oxidant conduit 12.
  • the casing seal 20 has a plurality of channels 22 for injecting water into the underground coal gasifier. As illustrated, the channels 22 can be adapted to direct the flow of the injected water toward the downhole end of the oxidant conduit 12 and/or toward the casing of the cased wellbore (not shown).
  • FIG. 1 An end view of the of the oxidant/water injection tool 10 is shown in Figure 2.
  • FIG. 3 A cutaway view of a section of a cased wellbore of an underground coal gasifier including the oxidant/water injection tool 10 is shown in Figure 3.
  • oxidantVwater injection tool 10 is inserted downhole into the cased wellbore of the gasifier through an injection well 23.
  • Casing seal 20 is configured to secure the annular space 25 between the oxidant conduit 12 and the casing 27 of the cased wellbore that extends between an injection well and a production well of the gasifier.
  • Coiled tubing 30 is fluidly connected to the oxidant conduit 12 at an uphole end 17 of the conduit, and supplies downhole oxidant to the oxidant/water injection tool 10.
  • the annular space 25 between the oxidant conduit 12 and the casing 27 of the cased wellbore is filled with water via a well head 32 of the injection well 23.
  • Oxidant and water are provided to the underground coal gasifier by way of the oxidant/water injection tool 10, with oxidant (e.g., substantially pure oxygen) injected via the opening 15 of the oxidant conduit 12, and water via the plurality of channels 22 in the casing seal 20.
  • oxidant e.g., substantially pure oxygen

Abstract

L'invention concerne un dispositif et un procédé pour fournir un oxydant et de l'eau dans une veine de charbon à des fins de gazéification souterraine de charbon.
PCT/AU2014/000526 2013-05-23 2014-05-20 Appareil d'injection d'oxydant et d'eau WO2014186823A1 (fr)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108518211A (zh) * 2018-03-29 2018-09-11 中为(上海)能源技术有限公司 用于煤炭地下气化工艺的氧化剂混合注入系统及操作方法
RU2706498C1 (ru) * 2016-08-24 2019-11-19 Чжунвей (Шанхай) Энерджи Текнолоджи Ко. Лтд Оборудование для нагнетания окислителя в процессе подземной газификации угля и его применение
CN112431582A (zh) * 2020-12-10 2021-03-02 上海飞舟博源石油装备股份有限公司 能够实现多种介质并输的煤炭地下气化系统及气化方法
US11066916B2 (en) 2017-01-12 2021-07-20 Zhongwei (Shanghai) Energy Technology Co. Ltd Nozzle and injection device for use in underground coal gasification process and method for operating injection device
CN113339044A (zh) * 2021-07-09 2021-09-03 山东科技大学 煤层注水孔内工况参数实时监测快速连接装置及方法
CN115247552A (zh) * 2021-04-27 2022-10-28 中国石油天然气集团有限公司 煤炭地下气化井筒的密封方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3240270A (en) * 1958-05-02 1966-03-15 Phillips Petroleum Co Recovery of hydrocarbons by in situ combustion
US4479540A (en) * 1981-06-05 1984-10-30 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Gasification of coal
US4512403A (en) * 1980-08-01 1985-04-23 Air Products And Chemicals, Inc. In situ coal gasification
WO2012109711A1 (fr) * 2011-02-18 2012-08-23 Linc Energy Ltd Allumage d'une veine de charbon souterraine dans un processus de gazéification de charbon souterrain (ucg)

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3240270A (en) * 1958-05-02 1966-03-15 Phillips Petroleum Co Recovery of hydrocarbons by in situ combustion
US4512403A (en) * 1980-08-01 1985-04-23 Air Products And Chemicals, Inc. In situ coal gasification
US4479540A (en) * 1981-06-05 1984-10-30 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Gasification of coal
WO2012109711A1 (fr) * 2011-02-18 2012-08-23 Linc Energy Ltd Allumage d'une veine de charbon souterraine dans un processus de gazéification de charbon souterrain (ucg)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2706498C1 (ru) * 2016-08-24 2019-11-19 Чжунвей (Шанхай) Энерджи Текнолоджи Ко. Лтд Оборудование для нагнетания окислителя в процессе подземной газификации угля и его применение
US10711587B2 (en) 2016-08-24 2020-07-14 Zhongwei (Shanghai) Energy Technology Co. Ltd Oxidizing agent injection equipment for underground coal gasification process and application thereof
US11066916B2 (en) 2017-01-12 2021-07-20 Zhongwei (Shanghai) Energy Technology Co. Ltd Nozzle and injection device for use in underground coal gasification process and method for operating injection device
CN108518211A (zh) * 2018-03-29 2018-09-11 中为(上海)能源技术有限公司 用于煤炭地下气化工艺的氧化剂混合注入系统及操作方法
CN108518211B (zh) * 2018-03-29 2024-01-30 中为(上海)能源技术有限公司 用于煤炭地下气化工艺的氧化剂混合注入系统及操作方法
CN112431582A (zh) * 2020-12-10 2021-03-02 上海飞舟博源石油装备股份有限公司 能够实现多种介质并输的煤炭地下气化系统及气化方法
CN112431582B (zh) * 2020-12-10 2022-06-21 上海飞舟博源石油装备股份有限公司 能够实现多种介质并输的煤炭地下气化系统及气化方法
CN115247552A (zh) * 2021-04-27 2022-10-28 中国石油天然气集团有限公司 煤炭地下气化井筒的密封方法
CN113339044A (zh) * 2021-07-09 2021-09-03 山东科技大学 煤层注水孔内工况参数实时监测快速连接装置及方法
CN113339044B (zh) * 2021-07-09 2023-08-25 山东科技大学 煤层注水孔内工况参数实时监测快速连接装置及方法

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