Patent Application
20140251621
The present disclosure is directed to methods and apparatus to extract fluids from subterranean reservoirs, particularly hydrocarbons and water reservoirs. More specifically, this disclosure provides methods and apparatuses to increase the recovery to surface of subterranean fluids, such as oil, water, and gas, from subterranean reservoirs using novel drilling methods, fluids and apparatus taught by my invention disclosure herein.
Conventionally, the oil and gas industry deploys massive hydraulic fracture of subterranean reservoirs, commonly known as “fracking,” to enhance fluid production from wells when a subterranean reservoir may not have sufficient conductivity to flow fluid through the natural reservoir permeability and into a wellbore connected to the surface of the earth at flow rates that are timely and or commercial. This “fracking” method hydraulically cracks the subterranean reservoir using water pumped down wells from surface at high pressure with triplex pumps, injecting chemicals such as polyacrylamides, and other chemicals into the subterranean earth reservoir. The cracks that this “fracking” method creates are uncontrolled and propagate in a direction dictated by the in-situ stress of the reservoir and require vast amounts of water and chemicals to be injected into said reservoirs. Hence the current art of “fracking” cannot create or increase reservoir conductivity in all directions from a wellbore placed in a subterranean reservoir, but can only produce and propagate cracks from the wellbore in directions perpendicular to the least principal in-situ stress of the reservoir. This hydraulic fracture treatment often allows reservoir fluids to be recovered at commercial rates, but has significant environmental impact due to large water injection volumes, induced micro-seismic events and large surface location foot prints to accommodate hydraulic fracturing equipment and sand injection with hydraulic fracture fluids.
Another conventional method used in the oil and gas industry to enhance a reservoir's fluid conductivity is to drill a horizontal bore through the reservoir. This method of drilling a wellbore horizontal in a fluid productive subterranean reservoir is combined with the hydraulic fracture of said horizontal wellbore to further enhance a reservoir's flow of fluid into wellbores. However, once again using fracture or “fracking methods,” the direction of the crack and hence the direction of the enhanced reservoir permeability due to said hydraulic fracturing is limited to the predetermined direction driven by the in-situ rock stresses and earth's overburden and tectonic stresses. What is needed are methods and apparatuses to more homogenously stimulate and enhance the reservoir's fluid flow that are not limited to directions controlled by in-situ stress nor require large amounts of fracture waters and chemicals to be pumped underground in both vertical or horizontal wellbores.
When it is desirous to produce a subterranean fluid to surface without the use of hydraulic fracturing, so called “fracking” technology, an alternative method for stimulating subterranean reservoir fluid flow to the surface of the earth is disclosed below. In one embodiment, enhanced subterranean fluid extraction methods and apparatuses are disclosed that allow for the directionally controlled drilling of a plurality of boreholes from a principal or common wellbore. These methods and apparatuses may enhance the injection of fluids into subterranean reservoirs for the purposes of enhanced oil, water, brine, mineral, and gas recovery, both in primary fluid recovery phases of a well's life as well as the secondary recovery phase of a well's life, commonly known as Enhanced Oil Recovery (EOR). Further, the disclosed methods and apparatuses may enhance the disposal and sequestering of fluids in subterranean rocks.
In some embodiments, methods and apparatuses for drilling said horizontal bores off perpendicular to the common wellbore are disclosed, such as using novel directional apparatus, using novel drilling fluids like cryogenic fluids and supercritical fluids, and using hydraulic assist methods to propel a small drilling string into the reservoir through a tubing or drill pipe string disposed in the wellbore.
In one embodiment, a method provides for the placement of a plurality of bores substantially perpendicular to the common wellbore at a given depth or position in the said common wellbore.
In one embodiment, multiple common boreholes may be placed in a subterranean reservoir wherein at least one of the common boreholes has a plurality of additional boreholes substantially horizontal to this common borehole.
Prior art practitioners attempting to drill boreholes from a substantially perpendicular direction to the common wellbore taught away from using metal alloy tubes and shafts and instead taught the use of rubber hoses and other flexible non-metal substances. In some embodiments, the use of super elastic and pseudoelastic alloys for drilling strings is possible, as opposed to other alloys or elastomeric tubes. In some embodiments, cryogenic fluids are pumped through said drilling strings. Moreover in some embodiments, a method may include the translation of a drilling tube through down hole tubulars, and down hole directional guidance devices using hydraulic drag forces, reverse thrusting hydraulic jets, and use of a system of fluids being pumped to propel the drilling string away from the common wellbore out into the reservoir using hydraulic drag forces.
In some embodiments, a method of assisting the moving of a drilling string may include applying a dragging hydraulic force whereby the drilling tools and drilling string can be passed through curved hydraulic conduits of a through tubing guidance apparatus to direct the tight radius change of the new borehole constructed to be substantially perpendicular to the common borehole.
In some embodiments, a method of drilling the substantially perpendicular bores to the common borehole may include using a method of underbalanced drilling wherein the drilling fluid used has a fluid hydrostatic pressure less than the reservoir pressure thereby allowing the production of the drilling fluid and the produced reservoir fluid simultaneously to the surface during the construction of the substantially perpendicular bores.
In some embodiments, stimulating the substantially perpendicular borehole to the common wellbore may be performed by means of pumping stimulation fluids, such as acids, bases, explosives, cryogenic fluids, and/or by deploying shaped charges down the constructed substantially perpendicular boreholes and thereafter detonating the shaped charges, further enhancing the reservoir conductivity along the substantially perpendicular bores constructed off the common wellbore without using massive hydraulic fracture techniques. This greatly reduces the environmental concerns of pumping billions of gallons per year of water, tons of chemicals, and sand into reservoir using hydraulic fracture methods and then flowing back these waters and chemicals to surface of the wells where they have to be disposed.
To meet the needs of enhancing reservoir fluid conductivity and increasing the recovery of fluids from subterranean strata as discussed above and herein, and to address the disadvantages of conventional drilled bore completions that use hydraulic fracture methods, the present application discloses a simple low cost method, small surface foot print system, and down hole apparatus to construct from a common wellbore a plurality of directional boreholes substantially perpendicular to said common wellbore.
In one embodiment, the method includes drilling a common wellbore and thereafter deploying on or near the distal end of a drill pipe string or tubing string a directional guidance tool. The drill or tubing string is then oriented in the required direction at the required depth by deploying, for example, a wire line gyro-directional tool, and by rotating the drill or tubing string at the surface. The exit direction of the distal end guidance tool is selected and fixed per the wire line deployed gyro or other such directional sensing tool deployed on wire line or communicated to the surface via pressure pulses or other radio or electromagnetic means. Once this guidance tool is oriented in the selected direction, the wire line is pulled out of the drill or tubing string and a guidance tubing string is disposed down the drill or tubing string where said guidance string is landed on its distal end inside the distal guidance tool. A drilling string or continuous conduit is then deployed and lowered from the surface through the guidance string and assisted through the guidance tool with the pumping of fluid through the guidance string, thereby hydraulically dragging the drill string through the guidance string and guidance tool and out into the reservoir. The drilling string has a drilling fluid pumped from the surface that is used to carry drilling cuttings to surface. Further, the drilling fluids may have a hydrostatic fluid weight less than the reservoir pressure, thereby allowing the reservoir fluids and drilling cuttings and drilling fluid to flow to the surface. The drilling string can be equipped with any of the commonly known drilling assemblies having a suite of devices such as drill bits, drilling motors, stabilizers, hydraulic and electric pulsed data communication tools (such as Logging While Drilling (LWD) tools), fluid jets, jars and other well-known drilling devices. The drilling string comprises a super elastic alloy that further assists the drilling string in bending through the curved path of the down hole guidance tool and guidance string.
In yet another embodiment, the drilling string can be equipped with a core device on the distal end that cores out, through a guidance device, a plug of well casing and cement prior to drilling the substantially perpendicular borehole into the subterranean reservoir. This core is extracted to the surface and then the drilling string and assembly are deployed back out into the position where the core was extracted by means of keeping the distal guidance tool fixed during coring and construction of the substantially perpendicular borehole from the common borehole. This procedure can be repeated multiple times at the same well position or depth by simply rotating the distal guidance tool and cutting another core followed by another substantially perpendicular bore to the common bore. Once the desired number of substantially perpendicular bores are created off the common wellbore at a given depth or position along a horizontal common bore, the drill or tubing string having the distal directional guidance tool can be moved to a new position and the above procedure is repeated, thereby constructing a plurality of substantially perpendicular bores to the common borehole at many positions along the length of the common borehole. A further embodiment uses an explosive device deployed into the well and through the guidance device to create a passage through the previously-drilled common wellbore, casing, and cement.
In another embodiment, a plurality of common wellbores are constructed in a reservoir strata, for example a large shale strata such as the Eagle Ford Shale of South Texas, having hundreds of feet of thickness wherein a horizontal wellbore is placed along the top 20 feet of the strata and boreholes are drilled from the common horizontal borehole radially like spokes from a wagon wheel hub, and said spoke positions are radially drilled all along the length of the horizontal common bore so that the horizontal common bore has many hundreds or more boreholes drilled radially around it at many hundreds of points along the horizontal length, and this is repeated in further horizontal wellbores placed deeper and under the previously mentioned horizontal borehole.
According to one embodiment of the disclosure, a method of increasing the recovery of fluid from a subterranean strata by constructing boreholes from a previously drilled common borehole comprises attaching to a well tubular conduit a directional guidance device having at least one internal conduit passage; deploying said well tubular conduit and said directional guidance device from a surface into said previously-drilled common borehole, wherein said well tubular conduit has a proximal end at the surface of the earth, and wherein said attached directional guidance device is attached near a distal end of said well tubular conduit; constructing a drilling string comprising a pseudoelastic alloy; attaching a drilling device to a distal end of said drilling string; translating said drilling string and said drilling device from said surface into said well tubular conduit through said directional guidance device; pumping a drilling fluid through said drilling string and said drilling device; drilling new boreholes from inside said previously-drilled common borehole into subterranean substances with said drilling device and said drilling string; flowing subterranean fluids into said common well borehole from said new boreholes; and producing fluids to said surface.
In certain embodiments, said subterranean substance being drilled is a subterranean strata; said pseudoelastic alloy is NITINOL; said drilling string comprises at least one tube having a distal end attached to said drilling device and a proximal end attached on said surface to a fluid pumping system; drilling fluid being pumped is at least at surface a cryogenic fluid; said drilling fluid comprises a fluid that has a hydrostatic weight less than a reservoir pressure of said subterranean strata that is in said common wellbore; said drilling string is attached on a proximal end to a surface drilling or workover rig; said drilling string is attached on a proximal end to a coiled tubing injection device; said drilling string is passed through a blowout preventer device; said drilling string comprises a string of threaded and jointed pipe joints; said drilling string comprises a string of continuous tubing; said drilling string comprises a mixed string of jointed and continuous tubing; said drilling device comprises at least one jet nozzle; said translating comprises translation that is at least assisted by a reactionary force of fluid jets on said drilling device pulling said drilling string away from said common wellbore; said translation is at least assisted in moving said drilling string through said well tubular conduit and said directional guidance device by hydraulic fluid drag forces imposed on an outer diameter of said drilling string by pumping a fluid from said surface down a well tubular conduit while said drilling string and said drilling device are deployed inside said well tubular conduit; said produced fluid is a reservoir fluid; said drilling device comprises a drilling motor; said drilling device comprises a pulsed data transmission device; said directional guidance device is rotated at a given well depth or length by rotating said well tubular conduit from said surface and a new borehole is drilled in another direction from said common wellbore; said common wellbore has had casing previously disposed in it and the method further comprises drilling through said casing and out beyond said casing into said subterranean strata; said directional guidance device is translated to a new depth position after drilling said borehole in said common wellbore and the method further comprises repeating the step of constructing said boreholes from said common bore hole at said a new depth position in said common wellbore; said drilling string is pulled from a new well bores directional placed from said common wellbore; a core drilling device is first translated through said well tubular conduit and said directional guidance device, a core is cut of a subterranean substance of said common wellbore, said core and coring device are pulled from the common wellbore, and a drilling string with a drilling device is thereafter deployed through said well tubular conduit and directional guidance device and out through the void created by said core device where drilling of substances is commenced off said common wellbore; an explosive charge is first translated through said well tubular conduit and directional guidance device, said charge is detonated at or near said common wellbore to form a passage or cavity out into said common wellbore, the detonated explosive charge is pulled from said well tubular conduit and said directional guidance device, said drilling string with drilling device is thereafter deployed through said well tubular conduit and said directional guidance device and out through a void in said common wellbore created by the explosive charge detonation where drilling said subterranean substances is commenced off said common wellbore through said void created by said explosive charge; said common wellbore is a substantially horizontal wellbore; said common wellbore is substantially vertical; said new boreholes from said common wellbore are substantially perpendicular to said common wellbore; said drilling string comprises a solid member comprising a super elastic alloy; said drilling string comprises a pseudoelastic alloy; and/or the step of drilling boreholes comprises drilling a plurality of common horizontal or vertical wellbores from said surface into said subterranean strata.
In another embodiment, a directional guidance apparatus comprises a body comprising at least one proximal entry fluid passage starting at a proximal end, said fluid passage extending through the said body and forming a curvature radius that terminates at an exit port located on a longitudinal side of said body.
In certain embodiments, the apparatus further comprises pipe threads on said proximal end; at least one additional fluid port hydraulically connected to the fluid passage starting at the said proximal end of said entry fluid passage, said at least one additional fluid port terminating in a position different than said longitudinal exit port; and/or at least one drag tube to be disposed inside said directional guidance apparatus fluid passage.
In one embodiment, a method of enhancing the injection of fluid from a surface into at least one subterranean strata by constructing boreholes from a previously drilled common borehole intersecting said subterranean strata, comprises attaching to a well tubular conduit a directional guidance device having at least one internal conduit passage; deploying said well tubular conduit and said directional guidance device from said surface into said previously drilled common borehole, wherein said tubular conduit has a proximal end at said surface of the earth and said attached directional guidance device is attached near a distal end of said tubular conduit; constructing a drilling string comprising a pseudoelastic alloy; attaching a drilling device to a distal end of said drilling string; translating said drilling string from said surface into said well tubular conduit through said directional guidance device; drilling new boreholes into subterranean substances with said drilling device and drilling string; injecting surface fluids into said common wellbore and out into said constructed boreholes; and injecting said surface fluids into said subterranean strata.
In certain embodiments, fluids from said at least one subterranean strata are produced to said surface from at least one additional wellbore not drilled from said common wellbore; said injected fluids comprise at least one gas; said injected fluids comprise supercritical fluids; said injected fluids comprise a liquid; said injected fluids comprise at least one cryogenic fluid; said injected fluids are injected into said common wellbore and into said reservoir through said new boreholes off of said common wellbore for a period of time and then fluids are returned from said new boreholes and said common wellbore to said surface; at least one hydraulic jarring device is attached to said drilling string; and/or at least a portion of said drilling string comprises a super elastic form of NITINOL.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
As used herein, “a” or “an” means one or more. Unless otherwise indicated, the singular contains the plural and the plural contains the singular. Where the disclosure refers to “perforations” it should be understood to mean “one or more perforations”.
As used herein, “surface” may refer to locations at or above the surface of the earth.
As used herein, “super elastic alloy” may refer to alloys that have an elastic (reversible) response to an applied stress, caused by a phase transformation between the austenitic and martensitic phases of a crystal. It is exhibited in shape-memory alloys. Super elasticity sometimes referred to as pseudoelasticity is from the reversible motion of domain boundaries during the phase transformation of an alloy, rather than just bond stretching or the introduction of defects in the crystal lattice (thus it is not true superelasticity but rather pseudoelasticity). Even if the domain boundaries do become pinned, they may be reversed through heating. Thus, a pseudoelastic material may return to its previous shape (hence, shape memory) after the removal of even relatively high applied strains. These alloys include but are not limited to a family of alloys known as Nitinol (an alloy comprising nickel and titanium and/or other elements).
Pseudoelasticity, sometimes referred to as superelasticity, is an elastic (reversible) response to an applied stress, caused by a phase transformation between the austenitic and martensitic phases of a crystal. It is exhibited in shape-memory alloys. Pseudoelasticity is from the reversible motion of domain boundaries during the phase transformation, rather than just bond stretching or the introduction of defects in the crystal lattice (thus it is not true superelasticity but rather pseudoelasticity).
Superelastic alloys belong to the larger family of shape-memory alloys. When mechanically loaded, a superelastic alloy deforms reversibly to very high strains—up to 10%—by the creation of a stress-induced phase. When the load is removed, the new phase becomes unstable and the material regains its original shape. Unlike shape-memory alloys, no change in temperature is needed for the alloy to recover its initial shape.
The term drilling herein is intended to encompass the art of cutting holes in substances, and includes but is not limited to the use of high pressure fluid jets, abrasive cutting jets, cutting bits, milling bits, which can include rotational methods, as well as hammering methods.
A brief description of the method used to drill boreholes through a previously constructed common borehole largely perpendicular to said previously constructed common wellbore is disclosed herein. It should be noted that this method may be applied to all manners of recovery of subterranean substances, such as, but not limited to, oil, gas, bitumen, kerogen, tar, water, CO2, helium, methane, bromine, iodine, gold, silver, platinum, lithium, rare earths, etc.
Once the common borehole is constructed to the subterranean depth required, the well casing may or may not be grouted into the common wellbore. For casing is grouted into place, an additional step of this method includes first cutting or coring the casing. Once the common wellbore is drilled to the required depth, the drilling rig can be substituted with a work over rig, which may be a smaller, more economical surface rig. The work over rig can be used to deploy into the well a tubing or drill pipe string.
At a high level, the embodiment in
According to one embodiment of the present disclosure, the directional guidance device comprises a body with at least one proximal entry passage starting at a proximal end, said passage extending through the directional guidance device body said passage forms a curvature radius that terminates said passage through the directional guidance device body at an exit port located on a longitudinal side of said body representing an exit port substantially perpendicular to the proximal entry passage. In one embodiment, the directional guidance device has at least one additional port hydraulically connected to the main passage through the body wherein said additional port terminates in a position different than the longitudinal exit port. For example, said additional port in said passage through the directional guidance device terminates on the distal end of the directional guidance device.
Turning to
According to one embodiment, a second phase 120 of
According to one embodiment, during third phase 130, a drag tube 3 is lowered through well tubing 2 into the directional guidance device 1 from the surface using the workover rig draw works. This drag tube 3 can be attached to a drill string 10 as shown in phase 120 or other well tubular member well known to those familiar with the art of well construction. Examples of other drill strings include coiled tubing and jointed stick pipe. Once this drag tube 3 is lowered into place through the passage in the directional guidance device 1, it is held at the surface with slips, and a further jet drilling tube 4 having a drilling jetting bit assembly 5 on the distal end of said jet drilling tube 4 is lowered into said drag tube 3 from the surface, through the directional guidance device 1, and out into the cavity or bore created in phase 120 process by the previously discussed drilling device 20 of the second phase 120.
In one embodiment, the process of placing and passing the jet drilling tube 4 and jet drilling assembly 5 is assisted by pumping a drag fluid 6 from surface down drag tube 3 wherein said drag fluid assists in pulling said jet drilling tube 4 through said drag tube 3 which was previously disposed in the directional guidance device 1. A surface pump then is attached to the jet drilling tube 4 and fluid 21 is pumped down the jet drilling tube 4 and out the drilling jet bit assembly 5. Fluid 21 is returned to the common wellbore 12 and into casing 14 along with drilling substances and the combined fluid mix of fluid 6 and fluid 21 are flowed back to the surface. In one embodiment fluid 21 is cryogenic nitrogen. In another embodiment fluid 6 is a gas. In one embodiment, the jet drilling assembly 5 comprises reverse thrusting jet nozzles to assist in propelling the jet drilling tube 4 away from the common wellbore 12 and out into the subterranean strata 7 to form a new substantially perpendicular borehole 25 connected to the common borehole 12. In this embodiment, the method of surface lowering devices for, pushing, and translating the jet drilling tube 4 away from the common wellbore 12 can be accomplished with a surface coiled tubing injector head well known to those in the field of coiled tubing deployment in the oil and gas industry or a drilling rigs draw works. In one embodiment, jet drilling fluid 21 is nitrogen, in whole or in part, such that the high pressure nitrogen coming out of the jet nozzle 5 assists in lifting fluids from common wellbore 12, cuts the formation 7, and propels the jet drilling tube 4 with the reactionary force exerted on said jet drilling string 4 from the reactionary force of the nitrogen exiting the jets of jet drilling assembly 5.
Once the jet drilling bit of the third phase 130 extends a sufficient distance from common wellbore 12, jet drilling tube is extracted from the well to the surface and the drilling rig rotates the tubular string 2 to a new radial position at the same depth in common wellbore 12. The process of coring and creating a new borehole 25 at the new position in the common wellbore is repeated as depicted in phase 120. The step of coring can be eliminated in some cases where the casing and cement grout are cut with high pressure jetting fluids coming out of the jet bit drilling assembly 5. Or the core step can be replaced by an explosive perforating step wherein a wire line device having an explosive charge attached to a wireline truck is disposed down the drag tube 3 from the surface, and moved through the directional guidance device 1 and drag tube 3 by pumping a drag fluid 6 down the drag tube 3 whilst lowering the wireline. Once the explosive charge is fired, and the casing and cement grout is penetrated by the explosive charge, the wireline is retracted to the surface and a jet drilling string 4 is disposed down the drag tube, as discussed above in phase 130, to start drilling the formation 7 and creating a borehole 25. In embodiments involving open hole completions, the core or perforating step can be eliminated and the extraction of drag tube 3 is not required between the construction of each new radially drilled borehole 25. According to the present disclosure, different jet drilling fluids 21 are contemplated, including, for example, acids, nitrogen, gases, cryogenic liquids, bentonite gel fluids, guar gel liquid systems, polyacrylamide gel liquid systems, oil lubricants, salt waters, attipulgite clay salt water systems, and the like.
In one embodiment, borehole 25 is enlarged by jetting with high pressure fluid 21 and further enhancing the reservoir 7 fluid conductivity to the substantially perpendicular borehole 25 to the common wellbore 12. The enlargement by jetting of the borehole 25 can be done by pumping hydrochloric acid as fluid 6 down the jet drilling tube 4 while boring out away from the common wellbore 12 or jetting with acid while returning the jet drilling tube 4 to the common wellbore 12. In one embodiment, cold fluids, such as cryogenic nitrogen, are pumped down the jetting tube 4 to assist in cracking and jetting the formation 7 and casing 14. Furthermore, it is understood that the construction for at least a portion of the jet drilling tube 4 and drilling rod 11 may use alloys of pseudoelastic and or super elastic materials. These materials include the family of alloys known as NiTiNol.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, and composition of matter, means, methods and steps described in the specification. As one of ordinary skilled in the art will readily appreciate from the disclosure of the present invention, processes, devices, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, devices, manufacture, compositions of matter, means, methods, or steps.
This application claims the benefit of priority to U.S. Provisional Patent Application No. 61/772,798 to David Randolph Smith filed Mar. 5, 2013, and entitled “Through Tubing Perpendicular Boring Method and Apparatus,” which is hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61772798 | Mar 2013 | US |
