WO2015116261A1 - Scellement hermétique de puits par réactions aluminothermiques - Google Patents

Scellement hermétique de puits par réactions aluminothermiques Download PDF

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Publication number
WO2015116261A1
WO2015116261A1 PCT/US2014/061289 US2014061289W WO2015116261A1 WO 2015116261 A1 WO2015116261 A1 WO 2015116261A1 US 2014061289 W US2014061289 W US 2014061289W WO 2015116261 A1 WO2015116261 A1 WO 2015116261A1
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WO
WIPO (PCT)
Prior art keywords
thermite
reaction
plug
well
charge
Prior art date
Application number
PCT/US2014/061289
Other languages
English (en)
Inventor
William Edward LOWRY
Sandra Dalvit Dunn
Original Assignee
Olympic Research, Inc.
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 US14/168,868 external-priority patent/US20150211328A1/en
Priority claimed from US14/168,863 external-priority patent/US9228412B2/en
Priority claimed from US14/168,877 external-priority patent/US9394757B2/en
Priority claimed from US14/168,867 external-priority patent/US20150211327A1/en
Application filed by Olympic Research, Inc. filed Critical Olympic Research, Inc.
Publication of WO2015116261A1 publication Critical patent/WO2015116261A1/fr

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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
    • E21B33/00—Sealing or packing boreholes or wells
    • E21B33/10—Sealing or packing boreholes or wells in the borehole
    • E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
    • 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
    • E21B33/00—Sealing or packing boreholes or wells
    • E21B33/10—Sealing or packing boreholes or wells in the borehole
    • E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
    • E21B33/134—Bridging plugs

Definitions

  • This invention relates to methods for sealing a well using a thermite reaction charge placed or lowered into the well.
  • the invention has remedial and sealing applications for wells used in oil and natural gas production, as well as in other applications including sealing of wells used for underground storage of nuclear waste, sequestration of C0 2 , and the like.
  • thermal reaction is intended to refer to a broad class of chemical reactions which can be defined as an exothermic reaction which involves a metal reacting with a metallic or a non-metallic oxide to form a more stable oxide and the corresponding metal or non-metal of the reactant oxide.
  • This is a form of oxidation- reduction reaction which can be written in a general form as:
  • M is a metal or an alloy (typically, but not necessarily Aluminum) and A is either a metal or a non-metal
  • MO and AO are their corresponding oxides
  • ⁇ is the heat generated by the reaction.
  • AO is one of the species of Iron Oxide, such as Fe 2 0 3 or Fe 3 0 4 .
  • a typical thermite reaction is of the form 2A1 + Fe 2 0 3 ⁇ 2 Fe + A1 2 0 3 . The reaction produces a great deal of heat per unit of mass, and can attain a reaction temperature of approximately 3,000°C.
  • Thermite reactions have many uses, including welding, pyrotechnics, synthesis and processing of materials, and military applications. Background information on thermite reactions is described in the review article of Wang et al., Thermite reactions: their utilization for synthesis and processing of materials, J. Materials Science 28 (1993) pp. 3693- 3708; and in Fisher et al., A survey of combustible metals, thermites and intermetallics for pyrotechnic applications, presented at the 32 nd AIAA/ASME/SE/ASEE Joint Propulsion Conference, Lake Buena Vista, FL, July 1-3 1996.
  • a well 100 (shown in cross-section) defined by the inner walls of a formation 1 has a platform 2 in the form of a backfill or bridge plug inserted into the well.
  • a thermite charge 4 typically a compressed block consisting of a mixture of a metal fuel material (such as aluminum powder) and a metal oxide (such as iron oxide powder) is lowered to a position in the well with some form of rigid platform 2 (such as a bridge plug) supporting it.
  • the platform 2 can be either granular backfill material, cement, or a mechanical plug (bridge plug) protected by an insulating material (not shown) on its upper surface.
  • the thermite charge 4 is then ignited by an electrical means, shown as igniter 3.
  • the igniter can be located on the bottom, in the interior, or on the top of the thermite charge.
  • the thermite charge 4 burns in place as a self-sustaining exothermic reaction. The burning occurs in a reaction zone 10 which propagates upward through the thermite charge 4.
  • thermite charge forms a rigid hot plug 12 of a metal and oxide, ceramic-like material.
  • the heat of the reaction may melt into the borehole wall material as shown at 14 in Figure 1C, or melt through the steel well casing if one is present, to form a platform or sealing component.
  • Improvements to the plug and emplacement design of Figure 1 are described which allow tailoring the well sealing method to achieve specific performance objectives and improve the sealing characteristics of the resulting plug. These include dilution of the thermite reactants to control reaction pressure, peak temperature, reaction rate, and expansion characteristics of the resulting thermite plug. The use of dilution of the thermite reactants to form a thermite charge with specific layers, including relatively high and low reaction temperature layers, is also described. We also describe including additives to the reactant mixture to alter the melt properties, such as eutectic materials or low melting point oxides which will alter the viscosity of the product liquid phase.
  • a method of sealing a well comprising the steps of: lowering a thermite reaction charge into the well at a location where the well is to be sealed, the thermite reaction charge having a bottom or lower end; providing a lower support for the thermite reaction charge at the location; applying a heavy mass load to the thermite reaction charge at the location; igniting the thermite reaction charge at the bottom of the charge and conducting a thermite reaction in the thermite reaction charge while the heavy mass load is applied to the thermite reaction charge, the thermite reaction forming a plug in the well sealing the well; and removing the heavy mass load from the location.
  • a well sealing apparatus including a thermite reaction charge having a cylindrical body sized to fit within a well, an igniter for the thermite reaction charge, a heavy mass applying a massive load by means of gravity to the thermite reaction charge, a separator separating the heavy mass from the thermite reaction charge; and a means for raising and lowering objects into the well, the means connected to the heavy mass and lowering the heavy mass into the well, the separator allowing the means for raising and lowering to remove the heavy mass from the well after ignition and burning of the thermite reaction charge within the well.
  • the heavy mass can take the form of a cylinder of steel or other dense material.
  • a method of sealing a well comprising the steps of: lowering a thermite reaction charge into the well at a location where the well is to be sealed, wherein the thermite reaction charge lowered into the well has been diluted by addition of one or more additives to moderate an exothermic reaction produced by the thermite reaction charge when ignited, the moderating comprising substantially lowering the reaction temperature and reaction velocity within the thermite reaction charge from what they would otherwise be without the one or more additives to meet a specific design objective for the sealing of the well; and igniting the thermite reaction charge, the thermite reaction charge burning so as to form a plug in the well.
  • a method of sealing a well comprising the steps of: lowering a thermite reaction charge into the well at a location where the well is to be sealed, the thermite reaction charge comprising at least two layers of thermite reaction charge including a first relatively lower reaction temperature layer and a second relatively higher reaction temperature layer, wherein the first layer comprises a thermite reaction material which has been diluted by addition of one or more additives to moderate an exothermic reaction produced by the thermite reaction material when ignited, the moderating comprising lowering the reaction temperature and reaction velocity within the thermite reaction material from what they would otherwise be without the one or more additives; and igniting the first and second layers of the thermite reaction charge.
  • a well sealing apparatus comprising: a thermite reaction charge having a cylindrical body sized to fit within a well, the thermite reaction charge comprising at least two layers of thermite reaction charge including a first relatively lower reaction temperature layer and a second relatively higher reaction temperature layer, and an igniter for the relatively lower reaction temperature layer.
  • a thermite plug for a well comprising a thermite reaction charge formed as a generally cylindrical body of length L and a central longitudinal axis a; and an igniter for the thermite material, wherein the igniter is positioned axially and extends substantially the length L of the general cylindrical body along the longitudinal axis a to trigger an exothermic reaction in the thermite reaction material propagating substantially from the center of the cylindrical body outwardly in a radial direction.
  • an apparatus for sealing a well comprising a first thermite plug having a igniter, a thermite reaction charge and an upper surface; an insulating block having upper and lower surfaces, the lower surface of the insulating block proximate to the upper surface of the first thermite plug; and a second thermite plug having an igniter, a thermite reaction charge and a lower surface, wherein the lower surface of the insulating block is positioned proximate to the upper surface of the insulating block.
  • an apparatus for sealing a well comprising: a first thermite plug having a igniter, a thermite reaction charge and an upper surface; an insulating block having upper and lower surfaces, the lower surface of the insulating block proximate to the upper surface of the first thermite plug; and a second thermite plug having an igniter, a thermite reaction charge and a lower surface, wherein the lower surface of the insulating block is positioned proximate to the upper surface of the insulating block.
  • An another embodiment is directed to a method for sealing a well, comprising the steps of: forming a platform in the well by means of ignition of a first thermite plug lowered into the well and causing the first thermite plug to expand to form the platform in the well; and subsequently igniting a second thermite plug above the location of the platform.
  • the first thermite plug is surrounded by an expandable metal package.
  • the first thermite plug can take the form of a thermite reaction material having a reaction temperature substantially less than a reaction temperature of the second thermite plug.
  • a method of sealing a well comprising the steps of: a) lowering a cylinder of thermite reaction charge into a well proximate to a target plug zone location where the well is to be plugged, b) igniting the thermite material, the ignited thermite material forming a reaction zone, and c) continuously supplying additional thermite reaction charge from the cylinder to the reaction zone after performing the ignition step.
  • a thermite plug for a well comprising a thermite reaction charge having a generally cylindrical body with length L, a longitudinal axis a and an upper end and a lower end; and an igniter for the thermite material, wherein the igniter is proximate to the lower end of the cylindrical body; wherein the well has a target plug zone having an axial extent substantially less than the length L of the cylinder and wherein ignition of the lower end of the cylindrical body in a reaction zone results in the continuous feed of thermite reaction material into the reaction zone.
  • FIGs. 1A-1C illustrate charge placement, ignition and cooling phases for a prior art thermite plug emplacement and reaction well sealing method.
  • Fig. 5 is a schematic illustration of a thermite cylinder showing an ignition source located on the centerline (axis) of the thermite cylinder and resulting radial direction of expansion.
  • the cylinder of Fig. 5 has pre-established cleavage planes formed in the thermite cylinder to foster the radial expansion.
  • FIGs. 6A-6D are an illustration of an embodiment with continuous feed of thermite into a reaction zone, with Fig. 6A showing an emplacement phase, Fig. 6B showing an ignition phase, Fig. 6C showing a progression of the reaction zone with continuous feed of the thermite charge into the reaction zone, and Fig. 6D showing the completion of the reaction phase and formation of a plug within the well.
  • Figs. 7A-7C are an illustration of an embodiment in which a relatively lower temperature expansive thermite charge is ignited and then a relatively higher temperature thermite charge is ignited above the lower temperature thermite charge.
  • Fig. 7A shows the emplacement phase
  • Fig. 7B shows the platform formation phase in which the lower temperature thermite charge is ignited
  • Fig. 7C shows the main (relatively higher temperature) charge ignition.
  • Figs. 8A-8C show a similar embodiment to Figs. 7A-7C, with an additional relatively lower temperature thermite charge located above the main higher temperature charge.
  • Fig. 8A shows the emplacement phase
  • Fig. 8B shows the two lower temperature thermite charges after ignition
  • Fig. 8C shows the main (relatively higher) charge after ignition. Both the lower and upper low temperature thermite charges are reacted and allowed to cool sufficiently to support and confine the higher temperature main charge as shown in the sequence Figs. 8 A to 8C.
  • the product e.g., plug 12 of Fig. 1C
  • the product is a porous matrix of metal oxide and metal.
  • the porosity results from entrained voids due to the charge preparation process, in which some porosity remains because the powders cannot be compacted to their maximum density, and other porosity is generated by entrained bubbles of the very small amount of gases generated in the reaction.
  • the porosity of the final plug material reduces its potential strength and causes it to be permeable to fluid flow.
  • the means 5, e.g., wireline, is connected to the heavy mass 22 and lowers the heavy mass 22, thermite reaction charge 4, separator (insulator) 20 and igniter 3 as a unit into the well.
  • the heavy mass can be lowered after the thermite reaction charge has been placed into the well at the desired location.
  • the igniter 3 may be of electrical in nature and a wire for the igniter is not shown, it being understood that any suitable chemical, electrical or pyrotechnic igniter could be used.
  • the details of the igniter are well known by persons skilled in the art, and are not particularly important.
  • the separator 20 allows the means 5 for raising and lowering to remove the heavy mass 22 from the well after ignition and burning of the thermite reaction charge within the well as shown in Figure 3.
  • Figure 2A the bore of the well 100 is plugged with a suitable bridge plug 2 which could be made of concrete, aggregate, or other material so that when the thermite reaction charge 4 is lowered into the well it rests on the plug 2 and the full weight of the heavy mass 22 is applied directly to the thermite reaction charge 4.
  • the method for sealing the well in Figures 2A-2C is as follows. First, a thermite reaction charge 4 is lowered into the well at a location where the well is to be sealed.
  • a lower support e.g., backfill or a bridge plug platform 2 for the thermite reaction charge is provided at the location, and the platform 2 can be lowered or otherwise formed in the well prior to lowering the thermite reaction charge; alternatively the bridge plug can be included as part of the thermite reaction charge assembly lowered into the well and formed in-situ, for example using the techniques of Figures 7A-7C and described subsequently.
  • the method continues with applying a heavy mass load to the thermite reaction charge at the location, as shown in Figures 2A and 2B by means of the massive cylinder 22 resting on the thermite reaction charge 4 while it is supported from below.
  • the method continues with a step of igniting the thermite reaction charge 4 and conducting a thermite reaction in the thermite reaction charge while the heavy mass load is applied to the thermite reaction charge, as shown in Fig. 2B.
  • the thermite reaction forms a plug which expands outwardly under load pressure from the heavy mass as the reaction occurs. This outward expansion is indicated by the arrows in Fig. 2B.
  • the reaction continues until all the fuel in the thermite charge is exhausted, all the while the load from the heavy mass is applied to the thermite reaction charge 4. As shown in Fig.
  • the resulting plug 12 is formed in the well, with the plug sufficiently hot that it melts portions of the surrounding formation 1 as indicated by 14, resulting in the plug 12 sealing the well.
  • the means for raising and lowering 5 is then activated to raise the heavy mass 22 (and any remnants of the separator 20) from the location where the plug 12 is formed.
  • a diluent to the thermite charge 4 such as metal oxides or eutectic materials, is optionally performed so as to lower the melting point of the plug 12 and prolong the time when the plug 12 is in a liquid or viscous state. This assists in insuring that the plug 12 is pressed firmly into the surrounding formation 1. Furthermore, the compressive load from the heavy mass 22 during burning of the thermite charge 4 reduces the porosity of the plug 12 and helps ensure against escape of gasses or other material from the well below the location of the plug 12. Second Embodiment.
  • the reaction For the purpose of sealing a well, however, the reaction must be controlled in order to contain the reaction products and form a monolithic plug material. Diluents and/or additives to the base mixture can be used to control the burn rate, peak temperature, and mechanical properties of the final plug. For instance, diluting the aluminum/iron oxide thermite formula with aluminum oxide (which is also a product of the reaction), moderates the reaction, and slows the reaction down to a rate that allows total containment of the thermite reaction with very little (gas) pressure generation.
  • thermite While stoichiometric aluminum/iron oxide thermite reaches a nominal peak temperature of 2965°C, by adding to the original mixture mass an additional 75% by mass aluminum oxide powder, the peak reaction temperature can be controlled to less than 1700°C and still sustain combustion. Dilutions greater than this percentage cannot sustain the thermite reaction, hence 75% by mass is considered an upper practical limit to the amount of dilution.
  • the diluted thermite reaction charge results in a slow, controlled reaction velocity, as low as 0.1 cm/sec, as compared to the raw/undiluted thermite mixture burn velocity of 10 to 100 cm/sec.
  • this dilution feature enables design of a thermite plug with a relatively cooler lower section that reacts first and heats up the well casing to a plastic but not molten state.
  • the lower, cooler plug can be designed such that it will expand radially and will swage the well casing outward to thereby fill the annular gap between the casing and the borehole/formation wall.
  • an upper, relatively hotter thermite reaction charge ignites and melts through the casing and into the rock/formation wall.
  • the cooler lower section prevents the molten material from the relatively hotter upper plug section from flowing or falling down into the annular void between the well casing and the formation wall, which would negate its sealing role.
  • FIG. 3 A shows a well 100 having a casing 30 separated from a borehole wall 31 in a formation 1, with an annular gap 33 separating the borehole wall 31 and the casing 30.
  • a plug or platform 2 is placed in the well at the location where the well is to be sealed.
  • a thermite reaction charge 4 is lowered into the well, e.g. by means of the wireline or drill pipe 5 and placed on the upper surface of the platform 2.
  • the thermite reaction charge 4 includes at least two layers of thermite reaction charge including a first relatively lower reaction temperature layer 40 and a second relatively higher reaction temperature layer 42.
  • the first layer 40 is in the form of a thermite reaction material, e.g., powdered mixture of aluminum and iron oxide, which has been diluted by addition of one or more additives, e.g., aluminum oxide, to moderate an exothermic reaction produced by the thermite reaction material 40 when it is ignited.
  • the moderating of the exothermic reaction is designed to lower the reaction temperature and reaction velocity within the thermite reaction material in the layer 40 from what they would otherwise be without the one or more additives.
  • the purpose of the moderation is to heat the well casing 30 to a plastic temperature such that radial expansion of the thermite charge during burning causes the casing 30 to expand radially and essentially swage against the rock formation 1 and close the annular gap 31.
  • Fig. 3B After ignition (by means of the igniter 3 at the lower end of the layer 40), the thermite reaction progresses upwardly within the layer 40 and the charge in the layer 40 expands radially outwardly to progressively swage the casing 30 against the rock wall in the formation 1, as shown at 32 in Fig. 3B.
  • thermite reaction has progressed to the top of the lower layer 40, the upper layer 42 of relatively higher reaction temperature thermite charge (for example undiluted aluminum and iron oxide powder) is ignited and the upper layer burns at a hotter temperature so as to melt the casing as indicated at 34 in Fig. 3B and the adjacent region of the rock formation 1.
  • thermite charge for example undiluted aluminum and iron oxide powder
  • a method of sealing a well comprising the steps of: lowering a thermite reaction charge 40 into the well at a location where the well is to be sealed, wherein the thermite reaction charge 40 lowered into the well has been diluted by addition of one or more additives to moderate an exothermic reaction produced by the thermite reaction charge when ignited, i.e., substantially lowering the reaction temperature and reaction velocity within the thermite reaction charge from what they would otherwise be without the one or more additives to meet a specific design objective for the sealing of the well; and igniting the thermite reaction charge (by means of igniter 3), the thermite reaction charge burning so as to form a plug in the well.
  • the one or more additives/diluents may take the form of a metal oxide.
  • Other additives could be used, for example as described in the article of Orru et al. cited in the Background section of this document.
  • the thermite reaction charge is preferably diluted by an amount of between 5 and 75 percent by mass.
  • the thermite reaction charge is diluted by addition of aluminum oxide by up to 75 percent and the reaction velocity of the thermite material is reduced to at or below 1 cm/second.
  • a method of sealing a well comprising the steps of: a) lowering a thermite reaction charge into the well at a location where the well is to be sealed (Fig. 3A), the thermite reaction charge comprising at least two layers of thermite reaction charge including a first relatively lower reaction temperature layer 40 and a second relatively higher reaction temperature layer 42, b) wherein the first layer 40 comprises a thermite reaction material which has been diluted by addition of one or more additives to moderate an exothermic reaction produced by the thermite reaction material when ignited, the moderating comprising lowering the reaction temperature and reaction velocity within the thermite reaction material from what they would otherwise be without the one or more additives; and c) igniting the first and second layers of the thermite reaction charge.
  • the first layer 40 is ignited by an igniter 3 installed in the thermite reaction charge specifically for this purpose, and the second layer 42 is ignited by the burning of the first layer reaching the lower edge of the second layer.
  • This method can include the step of placing a platform (2, Fig. 3A) into the well below or at the location where the well is to be sealed and placing the thermite reaction charge 40/42 onto the platform. As shown in Fig. 3A, the first layer 40 is positioned below the second layer 42, and the second layer 42 is ignited after the first layer 40 is ignited.
  • the well may further include a casing (30), and ignition of the first layer 40 causes the casing 30 to be swaged outwardly into contact with a formation 1 surrounding the casing 30.
  • a method of sealing a well comprising the steps of: a) forming a swage at a first location in the well by igniting a diluted thermite material (layer 40) lowered into the well proximate the first location so as cause the casing to heat to a plastic but not molten state and expand the plastic casing 30 against the borehole wall 31 and thereby close the annular gap 33 (see Fig. 3A), and b) igniting a second thermite material 42 above the first location to melt the casing and surrounding borehole wall and form a plug in the well, as shown in Fig. 3B.
  • a well sealing apparatus having been described in Fig. 3A including a) a thermite reaction charge 40/42 having a cylindrical body sized to fit within a well, the thermite reaction charge including a first relatively lower reaction temperature layer 40 and a second relatively higher reaction temperature layer 42; and b) an igniter 3 for the relatively lower reaction temperature layer.
  • the apparatus may further include a plug or platform 2 placed in the well below the thermite reaction charge.
  • the first relatively lower reaction temperature layer 40 is positioned below the second relatively higher reaction temperature layer 42.
  • FIG. 7A-7C A further example of this embodiment showing two thermite reaction charges with different reaction temperatures, separated by an insulating layer, is illustrated in Figs. 7A-7C and will be described subsequently.
  • FIG. 8A-8C A further example of this embodiment showing the main high temperature thermite charge confined by one low temperature expanding charge below, and another low temperature expanding charge above the main charge, is illustrated in Figs. 8A-8C and will be described subsequently.
  • a further example of this embodiment is to load the upper high temperature plug 42 with a heavy mass to compress the reacted charge, reduce its porosity, and press the reaction products into the borehole wall, in accordance with the teachings of Figs. 2A-2C.
  • the cylindrical plug of thermite 4 is ignited by a hot wire (or other suitable igniter 3) running essentially along the center axis a of the thermite plug 4 as shown in Fig. 5.
  • a hot wire or other suitable igniter 3
  • the reaction proceeds radially from the centerline of the thermite plug 4 and increases the diameter of the cylinder, not its length.
  • slippage/cleavage planes 60 are formed in the thermite material prior to combustion (i.e., at the time of manufacture or assembly of the thermite charge) to allow for radial expansion as indicated at 62, since the compacted thermite has sufficient tensile strength to counteract radial expansion without slippage/cleavage planes.
  • the cleavage/slippage planes are formed in any suitable manner in the thermite material, such as by means of a slitting saw, or preforming the thermite charge in pieces to produce the desired configuration.
  • An embodiment of this design could take the form of a modification of the thermite reaction charge of Fig. 3A in which the lower temperature layer 40 has an igniter positioned along the center axis of the layer 40 (in the manner shown in Fig. 5), such that when the lower temperature layer 40 is ignited the reaction proceeds in a radial direction so as to facilitate expansion of the thermite charge in the lower layer 40 against the casing 30 and swaging of the casing against the borehole wall 31 as shown in Fig. 3B at 32.
  • the reaction of the thermite charge in the upper region of the lower layer 40 causes ignition of the upper layer 42.
  • the thermite charge in the lower temperature layer 40 is fitted with slippage/cleavage planes 60 as shown in Fig. 5 so as to facilitate the radial expansion of the thermite in the lower layer against the well casing and the performance of the swaging operation.
  • a second example of this embodiment would be to configure the thermite reaction charge 4 of Fig. 2A with an igniter 3 positioned along the central or vertical axis of the thermite charge 4 and providing slippage/cleavage planes in the thermite charge as shown in Fig. 5.
  • a third example of this embodiment is to configure the thermite charge of Fig.
  • a fourth example of the design of Fig. 5 would be to incorporate the centrally located igniter in the thermite charge 80 of Fig. 7A.
  • the thermite plug includes a first portion which has the axially located igniter to trigger radial expansion of the thermite material (Fig. 5), and a second portion which has an igniter designed to trigger planar expansion (Fig. 4).
  • the thermite reaction charge which is ignited by the igniter may take the form of a thermite reaction charge diluted so as to reduce the exothermic reaction temperature and/or slow the reaction speed below what it would otherwise be without the addition of the diluents.
  • the thermite reaction charge could take the form of a thermite reaction charge diluted by between 5 and 75 % by mass with aluminum oxide, silica, calcium oxide, or other metal oxide.
  • a thermite plug for a well which includes a thermite reaction charge formed as a generally cylindrical body of length L and a longitudinal axis a (Fig. 5); and an igniter 3 (Fig. 5) for the thermite material, wherein the igniter 4 is positioned axially and extending substantially the length L of the general cylindrical body along the longitudinal axis a to trigger an exothermic reaction in the thermite reaction material propagating substantially from the center of the cylindrical body outwardly in a radial direction.
  • the thermite plug preferably includes two or more slippage/cleavage planes 60 formed in the thermite reaction charge designed to promoting radial expansion of the thermite reaction charge during combustion.
  • the thermite plug could include a first section 80 having the thermite reaction charge and igniter 3 as recited above, and a second section 84 in the form of a second thermite material and a second igniter 3 ' disposed to trigger an exothermic reaction propagating substantially in the axial direction.
  • FIGs. 7A-7D Another example, and perhaps a preferred example of this embodiment, is shown in Figs. 7A-7D. This example features a relatively low temperature expansive thermite plug is used to support relatively hotter thermite charge above.
  • a lower temperature expansive plug contained in an expandable metal cylinder (for example, a pleated thinwall metal cylinder) is first set off below the main charge, allowed to cool to form a platform with adequate strength, then the main thermite charge is ignited above the platform.
  • an expandable metal cylinder for example, a pleated thinwall metal cylinder
  • a plug for sealing a well includes a first thermite plug 80 having an igniter 3.
  • the plug 80 includes a thermite reaction charge such as a mixture of aluminum and iron oxide.
  • the plug 80 includes an upper surface 81.
  • An insulating block 82 is provided having upper and lower surfaces, the lower surface of the insulating block is proximate to the upper surface 81 of the first thermite plug 80 as shown in Fig. 7A.
  • a second thermite plug 84 is also provided having an igniter 3 '.
  • the second plug 84 includes a thermite reaction charge and a lower surface 85.
  • the lower surface of the second plug 84 is positioned proximate to the upper surface of the insulating block 82.
  • the thermite reaction charge in the first plug 80 may be diluted by between 5 and 75 % by mass with a metal oxide, alumina, silica or the like.
  • the insulating block 82 is provided so as to enable the first plug 80 to be ignited, expanding the first plug 82 to expand against the walls of the bore (see Fig. 7B) and then cooled, while preventing ignition of the second or upper plug 84.
  • FIGs. 8A-8C Another embodiment uses the expansive characteristics of the low temperature plug to confine, from above and below, the high temperature main thermite charge.
  • Figs. 8A-8C three thermite charges are used.
  • the lower plug 80 is a low temperature expanding plug and forms the structural platform for the assembly as previously described and shown in Figs. 7A-7B.
  • the upper low temperature expanding charge 86 is ignited.
  • the middle higher temperature plug 84 is ignited and its reaction temperature and pressure confined to the zone between the upper and lower plugs. See Fig. 8C.
  • the upper and lower plugs 86, 80 both have a centrally placed igniter 3 as in the embodiment of Fig. 5.
  • the upper plug 86 is separated from the middle plug 84 by means of an insulator 82.
  • a method for sealing a well comprising the steps of: a) lowering into the well a plug comprising a first thermite plug 80 having a igniter 3, a thermite reaction charge and an upper surface; an insulating block 82 having upper and lower surfaces, the lower surface of the insulating block proximate to the upper surface of the first thermite plug, and a second thermite plug 84 having an igniter 3', a thermite reaction charge and a lower surface, wherein the lower surface of the second plug is positioned proximate to the upper surface of the insulating block; b) igniting the first thermite plug 80 so as to cause a thermite reaction in the first thermite plug, the first thermite plug expanding so as to form a plug in the well (Fig. 7B); and c) subsequently to step b) igniting the second thermit
  • a method for sealing a well comprising the steps of: a) lowering into the well a plug comprising a first thermite plug 80 having an igniter 3, a thermite reaction charge and an upper surface; an insulating block 82 having upper and lower surfaces, the lower surface of the insulating block proximate to the upper surface of the first thermite plug, a second thermite plug 84 having an igniter 3', and thermite reaction charge and a lower surface, wherein the lower surface of the second plug is positioned proximate to the upper surface of the insulating block, and a third thermite plug 86 having an igniter 3, a thermite reaction charge and an upper surface; a second insulating block 82 having upper and lower surfaces, the upper surface of the second insulating block proximate to the lower surface of the third thermite plug 86; b) igniting the first thermite plug 80 having an igniter 3, a thermite reaction charge and an upper
  • the thermite reaction charge in the first thermite plug takes the form of a thermite reaction material which has been diluted by one or more additives to moderate an exothermic reaction produced by the thermite material when ignited, i.e., to lower the reaction temperature and reaction velocity within the thermite material from what they would otherwise be without the one or more additives.
  • the thermite reaction material in the first thermite plug has been diluted by an amount of between 5 and 75 percent by mass by addition of a metal oxide, silica, aluminum oxide, calcium oxide, etc. to the thermite reaction material.
  • the third thermite plug 86 may also be diluted in a similar fashion.
  • a method for sealing a well comprising the steps of: forming a platform in the well by means of ignition of a first thermite plug 80 lowered into the well (Figs. 7A, 7B); and subsequently igniting a second thermite plug 84 at a position above the location of the platform (Fig. 7C).
  • the first thermite plug 80 is surrounded by an expandable metal package 88 (Fig. 7A).
  • the first thermite plug 80 includes a thermite reaction material having a reaction temperature substantially less than the reaction temperature of the second thermite plug 84.
  • Another embodiment includes a third relatively low temperature expanding plug 86 on the top of the assembly, which is ignited simultaneously with the lowest plug 80 or shortly thereafter, forming a sealing plug to confine the subsequent reaction of the main high temperature plug 84.
  • a thermite charge package has to be smaller in diameter than the wellbore to allow insertion of the thermite charge to a desired depth.
  • the compacted charge package also has a finite gas filled porosity since it cannot be pressed to its theoretical maximum density.
  • the plug resulting from a thermite cylinder of a specific height will be shorter than its starting size by as much as 25% depending on the charge and product densities. This limits the amount of energy and material that can be placed in a defined or target plug zone within the well.
  • the thermite cylinder could be constructed in two or more layers, including a first relatively lower reaction temperature layer and a second relatively higher reaction temperature layer, in accordance with the design of Fig. 3A.
  • This design would be suitable for example in the situation where the well bore includes a casing as show in Fig. 3A and one wishes to design a swage for the casing as shown in Fig. 3B and explained above.
  • a thermite plug for a well is shown in the form of a thermite reaction charge 4 having a generally cylindrical body with length L, a longitudinal axis a (not shown, but see Fig. 5) and an upper end and a lower end 76, 78, respectively.
  • An igniter 3 for the thermite reaction charge 4 is positioned proximate to the lower end 78 of the cylindrical body.
  • the well has a target plug zone 70 having a longitudinal extent indicated by the bracket substantially less than the length L of the cylindrical thermite reaction charge 4, as shown in Fig. 6A.
  • Fig. 6A shows the placement of the thermite plug 4 into the well by means of a wireline 5 or other suitable means.
  • the well includes a plug or platform 2 below the target plug zone 70 on which the thermite reaction charge 4 rests.
  • Fig. 6B illustrates the ignition of the thermite reaction charge 4 by means of the igniter 3.
  • the ignition of the charge results in a reaction or combustion zone 10.
  • the cylindrical charge 4 continuously feeds a thermite reaction material into the reaction zone 10.
  • Fig. 6C shows the progression of the reaction zone 10 upwards into the cylinder, or, equivalently, the continuous feed of thermite reaction material into the reaction zone.
  • the expansion of the thermite charge melts the wall of the formation 1 as indicated at 14 and forms a plug in the well.
  • Fig. 6B illustrates the ignition of the thermite reaction charge 4 by means of the igniter 3.
  • the ignition of the charge results in a reaction or combustion zone 10.
  • the cylindrical charge 4 continuously feeds a thermite reaction material into the reaction zone 10.
  • the reaction has proceeded to completion by the burning of the thermite reaction charge at the upper surface of the cylinder 76.
  • the resulting plug 12 completely fills the well and melts the surrounding formation 1 as indicated at 14 along the entire length of the target plug zone 70, forming a seal for the well.
  • An additional example of this embodiment is to load the charge 4 with a mass 22 as shown in Figure 2A, providing additional downward force to the thermite charge 4 in the reaction zone 10 of Figure 6C.
  • a method of sealing a well comprising the steps of a) lowering a cylinder of thermite reaction charge (4) into a well proximate to a location where the well is to be plugged (Fig. 6A), b) igniting the thermite material, the ignited thermite material forming a reaction zone (Fig. 6B), and c) continuously supplying additional thermite reaction charge from the cylinder to the reaction zone after performing the ignition step (Figs. 6C and 6D).
  • the cylinder has an upper and a lower end, and wherein the igniting step b) comprises igniting the lower end of the cylinder.
  • thermite reaction charge 4 has been diluted by one or more additives to moderate an exothermic reaction produced by the thermite material when ignited, the moderating comprising lowering the reaction temperature and reaction velocity within the thermite material from what they would otherwise be without the one or more additives.
  • thermite reaction charge 4 could be formed as two or more layers including a first relatively lower reaction temperature layer and a second relatively higher reaction temperature layer in accordance with the teachings of the embodiment of Fig. 3 A and 3B.
  • Another variation is to use the continuous feed thermite plug 4 as the hot plug 42 as shown in Figure 3A, to increase the amount of energy and material deposited in the plug zone.

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  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
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Abstract

Selon l'invention, des puits sont hermétiquement scellés à l'aide de mélanges de réaction aluminothermique insérés dans les puits. Le mélange de réaction peut être dilué par ajout d'oxydes métalliques, de silice, ou autres, par la maîtrise d'une pression de réaction, d'un pic de température, d'un taux de réaction et des caractéristiques de dilatation du bouchon de thermite résultant. L'utilisation de la dilution des réactifs de thermite peut prendre la forme d'un mélange aluminothermique ayant des couches précises, comprenant des couches de température à réaction relativement élevée et faible. La source d'allumage peut être orientée de façon à obtenir une commande directionnelle sur la dilatation du produit, y compris la dilatation radiale ou axiale. Le mélange peut être chargé avec une grande masse afin de comprimer le bouchon de thermite résultant dans la paroi de trou de forage et de réduire sa porosité pendant le processus de réaction. Une autre variation entraîne la distribution continue des réactifs aluminothermiques à la zone de réaction. L'invention porte également sur différentes combinaisons et permutations des concepts inventifs susmentionnés.
PCT/US2014/061289 2014-01-30 2014-10-20 Scellement hermétique de puits par réactions aluminothermiques WO2015116261A1 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
US14/168,868 US20150211328A1 (en) 2014-01-30 2014-01-30 Well sealing via thermite reactions
US14/168,863 US9228412B2 (en) 2014-01-30 2014-01-30 Well sealing via thermite reactions
US14/168,877 2014-01-30
US14/168,868 2014-01-30
US14/168,867 2014-01-30
US14/168,877 US9394757B2 (en) 2014-01-30 2014-01-30 Well sealing via thermite reactions
US14/168,863 2014-01-30
US14/168,867 US20150211327A1 (en) 2014-01-30 2014-01-30 Well sealing via thermite reactions

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO20151689A1 (en) * 2015-12-09 2017-06-12 Interwell P&A As Ignitor, system and method of electrical ignition of exothermic mixture
WO2017137226A1 (fr) 2016-02-11 2017-08-17 Interwell P&A As Outil d'exploitation de puits et procédés de formation d'une barrière de puits permanente
CN107355197A (zh) * 2016-05-10 2017-11-17 中国石油天然气股份有限公司 封井装置和封井方法
GB2551693A (en) * 2016-05-24 2018-01-03 Bisn Tec Ltd Down-hole chemical heater and methods of operating such
DE102016015064A1 (de) 2016-12-19 2018-06-21 Elektro-Thermit Gmbh & Co. Kg Stoffgemisch zum Verschließen von Erdöl- oder Erdgasbohrungen
CN110067505A (zh) * 2019-04-24 2019-07-30 北京中矿新峰科技有限公司 一种适用于切顶沿空留巷的全液压切锚一体机
US10738567B2 (en) 2016-09-30 2020-08-11 Conocophillips Company Through tubing P and A with two-material plugs
WO2020169977A1 (fr) * 2019-02-20 2020-08-27 Panda-Seal International Ltd Procédé aluminothermique d'abandon d'un puits
US10871050B2 (en) 2016-09-30 2020-12-22 Conocophillips Company Nano-thermite well plug
IT201900014427A1 (it) 2019-08-08 2021-02-08 Eni Spa Metodo per sigillare un pozzo.
WO2021038254A1 (fr) * 2019-08-30 2021-03-04 Panda-Seal Limited Procédé de fermeture d'un puits
CN113027374A (zh) * 2021-04-14 2021-06-25 盘锦博程实业有限公司 双级温控自密封装置
NO20210354A1 (en) * 2021-03-19 2022-09-20 Interwell P&A As Sedimented thermite in well
US11905789B2 (en) 2017-03-11 2024-02-20 Conocophillips Company Helical coil annular access plug and abandonment

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3205947A (en) * 1962-02-26 1965-09-14 Phillips Petroleum Co Device and process for igniting an oil stratum
US4464989A (en) * 1983-05-13 1984-08-14 The United States Of America As Represented By The United States Department Of Energy Integral low-energy thermite igniter
US5833001A (en) * 1996-12-13 1998-11-10 Schlumberger Technology Corporation Sealing well casings
US20030145924A1 (en) * 2002-02-05 2003-08-07 Greg Carter Pyrotechnic thermite composition
US6805832B2 (en) * 2001-07-09 2004-10-19 Jonathan Mohler Thermite torch cutting nozzle
WO2006137920A2 (fr) * 2004-10-25 2006-12-28 Nanotechnologies, Inc. Systeme de declenchement photonique de materiaux nanoenergetiques
WO2013135583A2 (fr) * 2012-03-12 2013-09-19 Interwell Technology As Procédé d'opération dans un puits

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3205947A (en) * 1962-02-26 1965-09-14 Phillips Petroleum Co Device and process for igniting an oil stratum
US4464989A (en) * 1983-05-13 1984-08-14 The United States Of America As Represented By The United States Department Of Energy Integral low-energy thermite igniter
US5833001A (en) * 1996-12-13 1998-11-10 Schlumberger Technology Corporation Sealing well casings
US6805832B2 (en) * 2001-07-09 2004-10-19 Jonathan Mohler Thermite torch cutting nozzle
US20030145924A1 (en) * 2002-02-05 2003-08-07 Greg Carter Pyrotechnic thermite composition
WO2006137920A2 (fr) * 2004-10-25 2006-12-28 Nanotechnologies, Inc. Systeme de declenchement photonique de materiaux nanoenergetiques
WO2013135583A2 (fr) * 2012-03-12 2013-09-19 Interwell Technology As Procédé d'opération dans un puits

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10883329B2 (en) 2015-12-09 2021-01-05 Interwell P&A As Ignitor, system and method of electrical ignition of exothermic mixture
WO2017097663A1 (fr) * 2015-12-09 2017-06-15 Interwell P&A As Allumeur, système et procédé d'allumage électrique de mélange exothermique
NO20151689A1 (en) * 2015-12-09 2017-06-12 Interwell P&A As Ignitor, system and method of electrical ignition of exothermic mixture
WO2017137226A1 (fr) 2016-02-11 2017-08-17 Interwell P&A As Outil d'exploitation de puits et procédés de formation d'une barrière de puits permanente
CN107355197A (zh) * 2016-05-10 2017-11-17 中国石油天然气股份有限公司 封井装置和封井方法
GB2551693A (en) * 2016-05-24 2018-01-03 Bisn Tec Ltd Down-hole chemical heater and methods of operating such
EP3789582A1 (fr) 2016-05-24 2021-03-10 BiSN Tec Ltd Élément chauffant chimique de fond de trou et procédés de fonctionnement associés
GB2551693B (en) * 2016-05-24 2021-09-15 Bisn Tec Ltd Down-hole chemical heater and methods of operating such
US10871050B2 (en) 2016-09-30 2020-12-22 Conocophillips Company Nano-thermite well plug
US11480026B2 (en) 2016-09-30 2022-10-25 Conocophillis Company Nano-thermite well plug
US12010970B2 (en) 2016-09-30 2024-06-18 Conocophillips Company Nano-thermite well plug
US10738567B2 (en) 2016-09-30 2020-08-11 Conocophillips Company Through tubing P and A with two-material plugs
US11401777B2 (en) 2016-09-30 2022-08-02 Conocophillips Company Through tubing P and A with two-material plugs
DE102016015064A1 (de) 2016-12-19 2018-06-21 Elektro-Thermit Gmbh & Co. Kg Stoffgemisch zum Verschließen von Erdöl- oder Erdgasbohrungen
US11905789B2 (en) 2017-03-11 2024-02-20 Conocophillips Company Helical coil annular access plug and abandonment
WO2020169977A1 (fr) * 2019-02-20 2020-08-27 Panda-Seal International Ltd Procédé aluminothermique d'abandon d'un puits
CN110067505A (zh) * 2019-04-24 2019-07-30 北京中矿新峰科技有限公司 一种适用于切顶沿空留巷的全液压切锚一体机
CN110067505B (zh) * 2019-04-24 2024-04-19 北京中矿新峰科技有限公司 一种适用于切顶沿空留巷的全液压切锚一体机
IT201900014427A1 (it) 2019-08-08 2021-02-08 Eni Spa Metodo per sigillare un pozzo.
WO2021038254A1 (fr) * 2019-08-30 2021-03-04 Panda-Seal Limited Procédé de fermeture d'un puits
WO2022194655A1 (fr) 2021-03-19 2022-09-22 Interwell P&A As Procédé de formation d'une barrière permanente dans un puits
NO20210354A1 (en) * 2021-03-19 2022-09-20 Interwell P&A As Sedimented thermite in well
NO347929B1 (en) * 2021-03-19 2024-05-13 Interwell P&A As Sedimented thermite in well
US12129736B2 (en) 2021-03-19 2024-10-29 Interwell P&A As Method for providing a permanent barrier in a well
CN113027374A (zh) * 2021-04-14 2021-06-25 盘锦博程实业有限公司 双级温控自密封装置

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