US20100006289A1 - Method and apparatus for sealing abandoned oil and gas wells - Google Patents
Method and apparatus for sealing abandoned oil and gas wells Download PDFInfo
- Publication number
- US20100006289A1 US20100006289A1 US12/465,605 US46560509A US2010006289A1 US 20100006289 A1 US20100006289 A1 US 20100006289A1 US 46560509 A US46560509 A US 46560509A US 2010006289 A1 US2010006289 A1 US 2010006289A1
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- United States
- Prior art keywords
- casing
- bismuth
- alloy material
- tin alloy
- plug
- 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.)
- Abandoned
Links
- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000007789 sealing Methods 0.000 title claims abstract description 12
- 239000000956 alloy Substances 0.000 claims abstract description 77
- 238000010438 heat treatment Methods 0.000 claims abstract description 41
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 37
- 239000000463 material Substances 0.000 claims abstract description 34
- 229910001128 Sn alloy Inorganic materials 0.000 claims abstract description 31
- 239000004568 cement Substances 0.000 claims abstract description 21
- JWVAUCBYEDDGAD-UHFFFAOYSA-N bismuth tin Chemical compound [Sn].[Bi] JWVAUCBYEDDGAD-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000007787 solid Substances 0.000 claims abstract description 15
- 239000002002 slurry Substances 0.000 claims abstract description 10
- 239000012530 fluid Substances 0.000 claims abstract description 6
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims description 15
- 229910001152 Bi alloy Inorganic materials 0.000 claims description 11
- 230000005496 eutectics Effects 0.000 claims description 3
- 239000012768 molten material Substances 0.000 claims description 2
- 230000004888 barrier function Effects 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 15
- 239000007788 liquid Substances 0.000 description 7
- 239000000203 mixture Substances 0.000 description 5
- 229910052797 bismuth Inorganic materials 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000005755 formation reaction Methods 0.000 description 3
- 239000004576 sand Substances 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000001965 increasing effect Effects 0.000 description 2
- 231100000252 nontoxic Toxicity 0.000 description 2
- 230000003000 nontoxic effect Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
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- 230000018109 developmental process Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000006023 eutectic alloy Substances 0.000 description 1
- 239000000374 eutectic mixture Substances 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- -1 gravel Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000003673 groundwater Substances 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
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Images
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
- E21B33/12—Packers; Plugs
- E21B33/1208—Packers; Plugs characterised by the construction of the sealing or packing means
-
- 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
- E21B36/00—Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones
- E21B36/04—Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones using electrical heaters
Definitions
- This invention relates to a method and apparatus for sealing abandoned oil and gas wells and, more particularly, to sealing abandoned oil and gas well utilising an eutectic alloy which expands upon passage from the liquid to solid state.
- a steel cap was sealingly welded to the top of the outermost casing.
- Such a cap forms a “last barrier” to the seepage of any gas through the cement within the casing.
- the steel cap is usually placed on the top of the casing beneath the ground surface a certain distance, usually six feet or so, to prevent the casing from being contacted by farm implements and other earth moving or working equipment when agricultural land is being worked following well abandonment.
- a method for sealing an oil or gas well comprising positioning a melted bismuth/tin alloy material within a casing to form a plug within said casing when said liquefied alloy material solidifies within said casing.
- apparatus to allow a molten bismuth-tin alloy material to be positioned as a plug within an oil or gas well, said apparatus comprising means to add molten eutectic material to said casing at a predetermined location within said casing so as to form a solid plug within said casing when said liquefied alloy material cools and means to add a force balancing material to said casing on the top of said molten material.
- a method of sealing an abandoned oil or gas well comprising removing the cap on the top of the outer casing of said well, lowering and positioning a melted bismuth/tin alloy material within said casing to form a plug within said casing when said liquefied alloy material solidifies within said casing, positioning a force balancing material on the top of said melted bismuth/tin alloy material and allowing said melted bismuth/tin alloy to cool.
- a method for sealing an oil or gas well comprising positioning a predetermined quantity of melted bismuth/tin alloy material within a casing to form a plug wholly within said casing when said liquified alloy material cools and solidifies within said casing.
- FIG. 1A is a diagrammatic side and cutaway view of the solidified alloy plug within the alloy heater which has been lowered into the casing of an oil or gas well and which is attached to the surface controlled wireline;
- FIG. 1B is a diagrammatic view similar to FIG. 1A but showing the alloy heater in operation with the alloy in a molten state;
- FIG. 1C is a diagrammatic view similar to FIGS. 1A and 1B but illustrating the alloy heater being withdrawn from the well and leaving the molten alloy within the well;
- FIG. 1D is a diagrammatic side view of the alloy plug left in place within the well in its cooled and solid state
- FIG. 2 is a diagrammatic view of the components utilised to form the alloy plug within the well casing.
- FIG. 3 is an enlarged side view of the heating tool used to melt the bismuth-tin alloy and to carry the cement slurry which is deposited on the alloy material.
- an oil or gas well is shown generally in enlarged form at 100 in FIG. 1 . It comprises production casing illustrated generally at 101 which is cemented in and surrounded with cement 102 . A solid cement plug 103 is illustrated in place at the position of interest within the production casing 101 . The setting and formation of the cement plug 103 is well known in the art.
- FIG. 2 The components generally used for setting and forming the bismuth-tin alloy plug are best illustrated in FIG. 2 .
- Such components comprise a power control unit 104 located on the surface 114 which also serves as the source of input power, generally 480 volt three-phase alternating current which is subsequently rectified to adjustable voltage DC current for transmission to a heating tool 111 .
- the required power connections 105 are connected to a wireline spool 110 and extend from the spool 110 downhole by way of wireline cables 113 to an attachment 115 of the heating tool 111 which is diagrammatically illustrated in position within the production casing 101 with the cement or bridge plug 103 illustrated as being in place.
- a lubricator 112 to maintain a pressure seal may also be required as the cables 113 and heating tool 111 move up and down within the well casing 101 .
- the longitudinal and circular heating tool 111 is illustrated in greater detail in FIG. 3 .
- the power carrying cables 113 extend through an attachment point 115 on the tool 111 and terminate at an instrument pod 120 .
- the instrument pod 120 contains the necessary electronics to monitor downhole performance of the heating tool 111 and also provides for power transfer from the cables 113 to the circumferential alloy heating heaters 121 to be described in greater detail hereafter.
- the heating tool 111 contains a first circular cavity 122 (see also FIG. 1A ) adapted to hold the bismuth-tin alloy in solid form and to allow the alloy to melt and run from the circular cavity 122 .
- the heating tool 111 further contains a second circular cavity 123 which is generally concentric to and of identical internal configuration to first circular cavity 122 although the length of second cavity 123 may be increased or decreased in order to hold a required amount of cement slurry 124 .
- a loading port 130 is also provided to allow the loading of alloy billets (not illustrated) or of liquid alloy material as 131 as well as a force balancing material such as a cement slurry 124 although other materials may be water, sand, gravel or other suitable and fluid materials.
- the pressure sealing material that is preferred in the present operation is a bismuth-tin alloy mixture having 58% by weight bismuth and 42% by weight tin alloy.
- Bismuth is the essential ingredient inasmuch as it is non-toxic and exhibits the valuable property that it expands volumetrically upon solidification from the liquid phase. This expansion causes an effective fluid seal when placed within a well casing in molten form. Tin is also non-toxic, hence the mixture can be tolerated in direct contact with fresh groundwater which is a desirable characteristic for a well plugging material.
- any composition of bismuth-tin alloy could be used, the most favorable is the aforementioned 58/42 composition because this mixture is a eutectic mixture melting and solidifying at 137 deg. C. This is the minimum temperature at which a bismuth-tin alloy can exist entirely as a liquid and, therefore, facilitates the process of in situ melting and placement of the alloy plug.
- bismuth material to form the sealing plug 132 illustrated in FIG. 1C is desirable for the principal reason that bismuth expands as it solidifies. This is advantageous since while the alloy is in liquid form, it will fill and run into interstices that might be used as eventual passageways for fugitive gas transmission and, as the alloy cools and solidifies, it expands to fill the constrained volume of the well casing and therefore forms a far better seal than that of a material that may contract or remain at the same volume upon cooling.
- the size of the plug 132 which is required will generally be known in order to utilise the correct quantity of alloy.
- a rule of thumb generally used in the art is that the plug 132 will be approximately three times in length as compared to the diameter of the casing 101 .
- this dimension will vary particularly if the wellhole is deep and pressures downhole are high in which event a plug of greater lengthwise dimension would be desirable.
- the plug 132 is wholly within the casing 101 , the magnitude of alloy required will be far more accurate than when the alloy material is being used to seal a geological formation outside the wellbore by way of perforations in the casing.
- a cap 133 ( FIG. 4 ) is attached to the bottom of heating tool 111 .
- Cylindrical bismuth-tin billets (not illustrated) may be added through the loading port 130 and positioned one on top of the other within the billet magazine 134 with the lowermost billet being in contact with the cap 133 .
- heat is applied to the heaters 121 which surround the circular billets in order to melt the billets within the cavity 122 .
- the heating is preferably of resistive or inductive nature but surface heating of the billets may conveniently be performed using other heating techniques.
- the heating is terminated following the melting of the billets and the bismuth-tin alloy solidifies with the cylindrical heating cavity 122 as also seen in FIG. 1A .
- the cap 133 is then removed and the tool 111 is ready for downhole operation.
- the tool 111 When it is desired to plug a well, the tool 111 is attached to the power and wireline cables 113 which lower and raise the heating tool 111 within the casing 101 .
- a predetermined quantity of force balancing material such as cement slurry 124 ( FIG. 3 ) is added to the tool 111 through the loading port 130 .
- the cement slurry is positioned on top of the solid alloy material 131 and is intended to remain in fluid form until it exits the heating tool 111 when the alloy plug is being formed.
- the quantity of cement slurry or other force balancing material is dependent upon the pressure which is acting on the plug but the quantity required need not be highly accurate since the cost of the force balancing material is not great.
- the heating tool 111 is lowered into the wellhole as best seen in FIGS. 1A and 2 until it contacts the bridge or cement plug 103 . Heat is then applied to the solid alloy material by the heaters 121 of the alloy heater 111 until its melting point is reached at which point gravity will tend to move the liquid alloy out of the cavity 122 ( FIG. 1A ) of the heating tool 111 as seen in FIG. 1B . The weight of the heating tool 111 is monitored and as the alloy 116 runs out of the heating tool 111 , the tool 111 is raised within the casing away from cement plug 103 and the liquid alloy forms a plug 132 within the casing 101 as best seen in FIG. 1C .
- the fluid force balancing material such as the liquid cement slurry will follow the liquefied alloy out of the heating tool 111 and forms a counterforce type layer on top of the alloy plug 132 . It will be observed that the action of the force balancing material on the molten alloy will have at least two interesting characteristics. First, since the alloy is at a temperature greater than the force balancing material, the contact between the force balancing material and the top of the liquefied alloy plug 132 will cool the top of the alloy faster than at the bottom. Thus, expansion of the alloy at the top of the plug 132 will occur before the alloy expands as it cools in the lower portions of the plug 132 .
- the heating tool 111 is withdrawn from the casing 101 by use of the wireline cables 113 and the heating operation is terminated as seen in FIG. 1C .
- a significantly improved plug 132 ( FIG. 1B ) is formed in the casing 101 which will reduce or eliminate the migration of gases to the surface though the well casing 101 .
- molten alloy material may be added through the loading port 130 rather than in solid billet form which liquefied alloy material will then run down within the heating cavities to the temporary cap 133 .
- the alloy material is then allowed to cool and the cap 133 is removed as described earlier.
- force balancing material has been described as being added to the heating tool and subsequently released by the tool upon the exit of the alloy plug material, it is also envisioned that the force balancing material could be added to the wellhole in other manners such as simply lowering an automatically or manually opening bucket or other container. Sand, for example, could simply be poured down the wellhole following the installation of the alloy plug.
- force balancing material described herein is preferably a cement slurry, other materials such as sand, gravel, water or other suitable materials could conveniently be used.
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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)
- Earth Drilling (AREA)
Abstract
Apparatus and method for forming a solid sealing plug of bismuth-tin alloy material within a well casing for sealing oil or gas wells. Solid alloy material is positioned within a heating tool and lowered to a position within the well casing where the seal is to be formed. The heating tool is heated to liquefy the alloy material and the alloy material then runs out of the heating tool and solidifies on top of a cement plug previously formed within the well casing. A cement slurry or other fluid material may subsequently be deposited on top of the liquefied alloy material to enhance the sealing of the alloy plug, to form a barrier to subsequent creep of the alloy plug when the alloy solidifies and to counteract any pressure acting vertically on the bottom of the plug.
Description
- This application claims the benefit of provisional patent application Ser. No. 61/052,999 filed May 13, 2008.
- This invention relates to a method and apparatus for sealing abandoned oil and gas wells and, more particularly, to sealing abandoned oil and gas well utilising an eutectic alloy which expands upon passage from the liquid to solid state.
- When oil and gas wells are shut in or abandoned, a regulatory framework exists which mandates the procedures and technology required to properly shut in or abandon the well. This is required to prevent so far as is possible the leakage of gas from the underground formations to the surface. Such leakage can have adverse consequences from unpleasant smells and site contamination to creating a possibly latent explosive condition or the release of a toxic gas such as hydrogen sulfide.
- Heretofore, following the addition of cement to the production and surface casings following abandonment, a steel cap was sealingly welded to the top of the outermost casing. Such a cap forms a “last barrier” to the seepage of any gas through the cement within the casing. The steel cap is usually placed on the top of the casing beneath the ground surface a certain distance, usually six feet or so, to prevent the casing from being contacted by farm implements and other earth moving or working equipment when agricultural land is being worked following well abandonment.
- Because of significant real estate developments caused by increasing population in urban areas, there may be a number of previously abandoned wells in proximity to areas being developed. Many operations may occur underground at depths considerably below the six feet level and the possibility of underground machinery being used which can contact and damage the casing and cap is much more likely now than years ago. It has also been found that in many abandoned wells, gas has migrated over time through the cement upwardly within the casing and a pressure head is formed directly below the welded steel cap. If the casing or cap is damaged, this trapped gas may escape giving rise to the aforementioned significant problems.
- According to one aspect of the invention, there is provided a method for sealing an oil or gas well comprising positioning a melted bismuth/tin alloy material within a casing to form a plug within said casing when said liquefied alloy material solidifies within said casing.
- According to a further aspect of the invention, there is provided apparatus to allow a molten bismuth-tin alloy material to be positioned as a plug within an oil or gas well, said apparatus comprising means to add molten eutectic material to said casing at a predetermined location within said casing so as to form a solid plug within said casing when said liquefied alloy material cools and means to add a force balancing material to said casing on the top of said molten material.
- According to yet a further aspect of the invention, there is provided a method of sealing an abandoned oil or gas well comprising removing the cap on the top of the outer casing of said well, lowering and positioning a melted bismuth/tin alloy material within said casing to form a plug within said casing when said liquefied alloy material solidifies within said casing, positioning a force balancing material on the top of said melted bismuth/tin alloy material and allowing said melted bismuth/tin alloy to cool. a method for sealing an oil or gas well comprising positioning a predetermined quantity of melted bismuth/tin alloy material within a casing to form a plug wholly within said casing when said liquified alloy material cools and solidifies within said casing.
- Specific embodiments of the invention will now be described, by way of example only, with the use of drawings in which:
-
FIG. 1A is a diagrammatic side and cutaway view of the solidified alloy plug within the alloy heater which has been lowered into the casing of an oil or gas well and which is attached to the surface controlled wireline; -
FIG. 1B is a diagrammatic view similar toFIG. 1A but showing the alloy heater in operation with the alloy in a molten state; -
FIG. 1C is a diagrammatic view similar toFIGS. 1A and 1B but illustrating the alloy heater being withdrawn from the well and leaving the molten alloy within the well; -
FIG. 1D is a diagrammatic side view of the alloy plug left in place within the well in its cooled and solid state; -
FIG. 2 is a diagrammatic view of the components utilised to form the alloy plug within the well casing; and -
FIG. 3 is an enlarged side view of the heating tool used to melt the bismuth-tin alloy and to carry the cement slurry which is deposited on the alloy material. - Referring now to the drawings, an oil or gas well is shown generally in enlarged form at 100 in
FIG. 1 . It comprises production casing illustrated generally at 101 which is cemented in and surrounded withcement 102. Asolid cement plug 103 is illustrated in place at the position of interest within theproduction casing 101. The setting and formation of thecement plug 103 is well known in the art. - The components generally used for setting and forming the bismuth-tin alloy plug are best illustrated in
FIG. 2 . Such components comprise apower control unit 104 located on thesurface 114 which also serves as the source of input power, generally 480 volt three-phase alternating current which is subsequently rectified to adjustable voltage DC current for transmission to a heating tool 111. The requiredpower connections 105 are connected to awireline spool 110 and extend from thespool 110 downhole by way ofwireline cables 113 to anattachment 115 of the heating tool 111 which is diagrammatically illustrated in position within theproduction casing 101 with the cement orbridge plug 103 illustrated as being in place. Alubricator 112 to maintain a pressure seal may also be required as thecables 113 and heating tool 111 move up and down within thewell casing 101. - The longitudinal and circular heating tool 111 is illustrated in greater detail in
FIG. 3 . Thepower carrying cables 113 extend through anattachment point 115 on the tool 111 and terminate at an instrument pod 120. Theinstrument pod 120 contains the necessary electronics to monitor downhole performance of the heating tool 111 and also provides for power transfer from thecables 113 to the circumferentialalloy heating heaters 121 to be described in greater detail hereafter. The heating tool 111 contains a first circular cavity 122 (see alsoFIG. 1A ) adapted to hold the bismuth-tin alloy in solid form and to allow the alloy to melt and run from thecircular cavity 122. The heating tool 111 further contains a secondcircular cavity 123 which is generally concentric to and of identical internal configuration to firstcircular cavity 122 although the length ofsecond cavity 123 may be increased or decreased in order to hold a required amount ofcement slurry 124. Aloading port 130 is also provided to allow the loading of alloy billets (not illustrated) or of liquid alloy material as 131 as well as a force balancing material such as acement slurry 124 although other materials may be water, sand, gravel or other suitable and fluid materials. - The pressure sealing material that is preferred in the present operation is a bismuth-tin alloy mixture having 58% by weight bismuth and 42% by weight tin alloy. Bismuth is the essential ingredient inasmuch as it is non-toxic and exhibits the valuable property that it expands volumetrically upon solidification from the liquid phase. This expansion causes an effective fluid seal when placed within a well casing in molten form. Tin is also non-toxic, hence the mixture can be tolerated in direct contact with fresh groundwater which is a desirable characteristic for a well plugging material. Whereas any composition of bismuth-tin alloy could be used, the most favorable is the aforementioned 58/42 composition because this mixture is a eutectic mixture melting and solidifying at 137 deg. C. This is the minimum temperature at which a bismuth-tin alloy can exist entirely as a liquid and, therefore, facilitates the process of in situ melting and placement of the alloy plug.
- The use of bismuth material to form the
sealing plug 132 illustrated inFIG. 1C is desirable for the principal reason that bismuth expands as it solidifies. This is advantageous since while the alloy is in liquid form, it will fill and run into interstices that might be used as eventual passageways for fugitive gas transmission and, as the alloy cools and solidifies, it expands to fill the constrained volume of the well casing and therefore forms a far better seal than that of a material that may contract or remain at the same volume upon cooling. - The size of the
plug 132 which is required will generally be known in order to utilise the correct quantity of alloy. A rule of thumb generally used in the art is that theplug 132 will be approximately three times in length as compared to the diameter of thecasing 101. Clearly, this dimension will vary particularly if the wellhole is deep and pressures downhole are high in which event a plug of greater lengthwise dimension would be desirable. But because theplug 132 is wholly within thecasing 101, the magnitude of alloy required will be far more accurate than when the alloy material is being used to seal a geological formation outside the wellbore by way of perforations in the casing. - In operation, there are several techniques that may be used to set up the heating tool 111 for downhole operation. Preferably, a cap 133 (
FIG. 4 ) is attached to the bottom of heating tool 111. Cylindrical bismuth-tin billets (not illustrated) may be added through theloading port 130 and positioned one on top of the other within thebillet magazine 134 with the lowermost billet being in contact with thecap 133. Thereafter, heat is applied to theheaters 121 which surround the circular billets in order to melt the billets within thecavity 122. The heating is preferably of resistive or inductive nature but surface heating of the billets may conveniently be performed using other heating techniques. The heating is terminated following the melting of the billets and the bismuth-tin alloy solidifies with thecylindrical heating cavity 122 as also seen inFIG. 1A . Thecap 133 is then removed and the tool 111 is ready for downhole operation. - When it is desired to plug a well, the tool 111 is attached to the power and
wireline cables 113 which lower and raise the heating tool 111 within thecasing 101. At this juncture, a predetermined quantity of force balancing material such as cement slurry 124 (FIG. 3 ) is added to the tool 111 through theloading port 130. The cement slurry is positioned on top of thesolid alloy material 131 and is intended to remain in fluid form until it exits the heating tool 111 when the alloy plug is being formed. The quantity of cement slurry or other force balancing material is dependent upon the pressure which is acting on the plug but the quantity required need not be highly accurate since the cost of the force balancing material is not great. - The heating tool 111 is lowered into the wellhole as best seen in
FIGS. 1A and 2 until it contacts the bridge orcement plug 103. Heat is then applied to the solid alloy material by theheaters 121 of the alloy heater 111 until its melting point is reached at which point gravity will tend to move the liquid alloy out of the cavity 122 (FIG. 1A ) of the heating tool 111 as seen inFIG. 1B . The weight of the heating tool 111 is monitored and as thealloy 116 runs out of the heating tool 111, the tool 111 is raised within the casing away fromcement plug 103 and the liquid alloy forms aplug 132 within thecasing 101 as best seen inFIG. 1C . The fluid force balancing material (not shown) such as the liquid cement slurry will follow the liquefied alloy out of the heating tool 111 and forms a counterforce type layer on top of thealloy plug 132. It will be observed that the action of the force balancing material on the molten alloy will have at least two interesting characteristics. First, since the alloy is at a temperature greater than the force balancing material, the contact between the force balancing material and the top of the liquefiedalloy plug 132 will cool the top of the alloy faster than at the bottom. Thus, expansion of the alloy at the top of theplug 132 will occur before the alloy expands as it cools in the lower portions of theplug 132. This enhances the seal at the top of thealloy plug 132 and forms resistance to any subsequent creep in theplug 132 caused by well pressure. Second, as the force balancing material solidifies on top of theplug 132, it also serves as a barrier to any subsequent creep of the alloy material in theplug 132 over time. - Following the release of the alloy material and the force balancing material, the heating tool 111 is withdrawn from the
casing 101 by use of thewireline cables 113 and the heating operation is terminated as seen inFIG. 1C . A significantly improved plug 132 (FIG. 1B ) is formed in thecasing 101 which will reduce or eliminate the migration of gases to the surface though thewell casing 101. - While the use of alloy billets has been described, it is envisioned that molten alloy material may be added through the
loading port 130 rather than in solid billet form which liquefied alloy material will then run down within the heating cavities to thetemporary cap 133. The alloy material is then allowed to cool and thecap 133 is removed as described earlier. - While the force balancing material has been described as being added to the heating tool and subsequently released by the tool upon the exit of the alloy plug material, it is also envisioned that the force balancing material could be added to the wellhole in other manners such as simply lowering an automatically or manually opening bucket or other container. Sand, for example, could simply be poured down the wellhole following the installation of the alloy plug.
- Although the force balancing material described herein is preferably a cement slurry, other materials such as sand, gravel, water or other suitable materials could conveniently be used.
- Many modifications will readily occur to those skilled in the art to which the invention relates and the particular embodiments described herein should be taken as illustrative of the invention only and not as limiting its scope as defined in accordance with the accompanying claims.
Claims (13)
1. A method for sealing an oil or gas well comprising positioning a melted bismuth/tin alloy material within a casing to form a plug within said casing when said liquefied alloy material solidifies within said casing.
2. A method as in claim 1 and further positioning a slurry cement material on the top of said melted bismuth/tin alloy material and allowing said melted bismuth/tin alloy to cool.
3. A method as in claim 2 wherein said bismuth-tin alloy material is melted by the application of heat with a heating tool downhole in said oil and/or gas well.
4. A method as in claim 3 wherein said bismuth-tin alloy material is positioned within said heating tool in a first solid form prior to being melted.
5. A method as in claim 4 wherein said heating tool is lowered within a well casing to an existing cement plug within said well casing with said bismuth-tin alloy in solid form and said force balancing material is positioned on top of said bismuth-tin alloy.
6. A method as in claim 5 wherein said bismuth-tin alloy is heated following the lowering of said heating tool within said well casing, said liquefied alloy material exiting said heating tool and said force balancing material exiting said heating tool following said alloy material.
7. A method as in claim 1 wherein a cap is initially removed from the top of the outer one of said casing to allow access to said casing.
8. Apparatus to allow a molten bismuth-tin alloy material to be positioned as a plug within an oil or gas well, said apparatus comprising means to add molten eutectic material to said casing at a predetermined location within said casing so as to form a solid plug within said casing when said liquefied alloy material cools and means to add a force balancing material to said casing on the top of said molten material.
8. Apparatus as in claim 7 wherein said molten eutectic material is a bismuth-tin alloy material.
9. Apparatus as in claim 8 wherein said means to add said bismuth-tin alloy material is an alloy heater with a first cylindrical cavity to hold said bismuth-tin alloy material in solid form and said means to add a force balancing material is a second cylindrical cavity to hold said force balancing material in a fluid form.
10. Apparatus as in claim 9 wherein said heating tool has a heating chamber which allows said bismuth-tin alloy in solid form to be liquefied within said heating tool.
11. Apparatus as in claim 10 wherein said means to add molten alloy material to said casing further includes power cables extending to said heating tool and a wireline to allow said heating tool to be raised and lowered within said well casing.
12. Method of sealing an abandoned oil or gas well comprising removing the cap on the top of the outer casing of said well, lowering and positioning a melted bismuth/tin alloy material within said casing to form a plug within said casing when said liquefied alloy material solidifies within said casing, positioning a force balancing material on the top of said melted bismuth/tin alloy material and allowing said melted bismuth/tin alloy to cool.
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US12/465,605 US20100006289A1 (en) | 2008-05-13 | 2009-05-13 | Method and apparatus for sealing abandoned oil and gas wells |
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US5299908P | 2008-05-13 | 2008-05-13 | |
US12/465,605 US20100006289A1 (en) | 2008-05-13 | 2009-05-13 | Method and apparatus for sealing abandoned oil and gas wells |
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US20100006289A1 true US20100006289A1 (en) | 2010-01-14 |
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US12/465,605 Abandoned US20100006289A1 (en) | 2008-05-13 | 2009-05-13 | Method and apparatus for sealing abandoned oil and gas wells |
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Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2480869A (en) * | 2010-06-04 | 2011-12-07 | Bisn Tec Ltd | A eutectic plug and heater for sealing well perforations |
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US10053950B2 (en) | 2012-12-20 | 2018-08-21 | Bisn Tec Ltd | Controlled heat source based down-hole plugging tools and applications |
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040104045A1 (en) * | 2002-11-06 | 2004-06-03 | Larovere Thomas A. | Cement heating tool for oil and gas well completion |
US6942032B2 (en) * | 2002-11-06 | 2005-09-13 | Thomas A. La Rovere | Resistive down hole heating tool |
US20060144591A1 (en) * | 2004-12-30 | 2006-07-06 | Chevron U.S.A. Inc. | Method and apparatus for repair of wells utilizing meltable repair materials and exothermic reactants as heating agents |
US7290609B2 (en) * | 2004-08-20 | 2007-11-06 | Cinaruco International S.A. Calle Aguilino De La Guardia | Subterranean well secondary plugging tool for repair of a first plug |
US7640965B2 (en) * | 2001-06-05 | 2010-01-05 | Shell Oil Company | Creating a well abandonment plug |
-
2009
- 2009-05-13 US US12/465,605 patent/US20100006289A1/en not_active Abandoned
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7640965B2 (en) * | 2001-06-05 | 2010-01-05 | Shell Oil Company | Creating a well abandonment plug |
US20040104045A1 (en) * | 2002-11-06 | 2004-06-03 | Larovere Thomas A. | Cement heating tool for oil and gas well completion |
US6942032B2 (en) * | 2002-11-06 | 2005-09-13 | Thomas A. La Rovere | Resistive down hole heating tool |
US7290609B2 (en) * | 2004-08-20 | 2007-11-06 | Cinaruco International S.A. Calle Aguilino De La Guardia | Subterranean well secondary plugging tool for repair of a first plug |
US20060144591A1 (en) * | 2004-12-30 | 2006-07-06 | Chevron U.S.A. Inc. | Method and apparatus for repair of wells utilizing meltable repair materials and exothermic reactants as heating agents |
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