Method for constructing a wellbore in an earth formation - Patents.com

Abstract

A closed-loop borehole configuration is disclosed having an unlimited geometry to accommodate irregular or difficult thermal gradients within a heat-producing formation. A working fluid is utilized in the loop to extract thermal energy therefrom. The loop and unlimited geometry are achieved using magnetic ranging of independent drilling operations that intersect from inlet and outlet wells to form interconnected sections. Adjustment operations are incorporated in combination with directional drilling to adjust the rock face, cool the entire system, and activate the borehole, specifically for processing to optimize heat transfer. The considerable freedom of borehole configuration is further optimized by the absence of mechanical obstructions, such as casings or liners, in the heat transfer zone.

Description

[Technical field]

[0001] The present invention is a heat-producing strata More specifically, the present invention relates to constructing a well in a particular strata To facilitate well positioning that maximizes thermal energy recovery from the thermal gradient strata It concerns optimizing excavation in [Background technology]

[0002] strata With the advent of improved drilling techniques to drill to greater depths and tolerate higher temperatures in deep wells, the suitability of certain well configurations has improved. strata Many advances have been made to make this possible.

[0003] To improve the efficiency of well positioning, the unification of drilling techniques, the chemistry of working fluids, Drilling The regulation unit actions, particularly with flow rate and ranking, may be combined to provide a given strata Efficient heat recovery must be achieved in the most complex and diverse thermal gradients in the

[0004] The present invention facilitates the ability to recover thermal energy despite the anomalies and complexities of thermal gradients.

[0005] One of the earlier developments in the field was embodied in U.S. Patent No. 6,247,313 to Moe, issued June 19, 2001. The invention relates to a geothermal field comprising a plurality of heat absorbing pits. Drilling There is a disclosure regarding the configuration. The disclosure does not mention a casing or liner, but is limited to the use of a fracture zone, an angular arrangement of parallel heat absorbing holes, and further limitations. Specifically, the teachings state: "The magnitude of the inclination angle depends on several factors, e.g., the temperature gradient in the rock, the length of the heat absorption pore, and the amount of water flow. Calculation of the angle is within the capabilities of a person skilled in the art and therefore will not be detailed herein. The angle is usually between 20° and 50°, preferably about 40°." Moreover, in order to maximize the extraction of heat from a given volume of rock, at least a substantial portion of the heat absorbing holes run parallel to one another. More preferably, the heat absorbing holes are arranged in one layer, or in several vertically spaced layers if necessary. Subject to the arrangement of vertically spaced layers, each layer having several heat absorbing holes allows the capacity of the plant to be increased without spreading the holes over a large area. This is of considerable importance when the amount of land available for development is not large.

[0006] The supply holes 3 and the return holes 4 are interconnected by four heat absorption holes 5, each with a diameter of 10 cm and a length of about 2000 m. The spacing between these holes 5 may be 100-150 m. They are drilled starting from the supply holes 3 and end at or close to the return holes 4. As it is difficult to directly hit the return holes 4 when drilling the heat absorption holes 5, a fracture zone 6 has been established in this area to achieve flow communication between the holes 4 and 5."

[0007] The teachings also, as emphasized, teach difficulties with inlet and outlet connections. On the downside, Moe's arrangement, despite its unusual nature, does not provide sufficient teaching regarding unlimited access to the slope, and thus the disclosure is limited to certain scenarios.

[0008] Shulman issued U.S. Patent No. 5,515,679 on May 14, 1996. The document teaches a closed-loop thermal energy recovery arrangement in various high temperature rock types, one of which is solid rock as distinguished in Shulman's disclosure. "The present invention relates to a novel method and apparatus employing liquid circulation in a closed pipe loop system whereby thermal energy in hot rocks underground is extracted, i.e., extracted, and transported to the surface for utilization. The hot rocks may be solid, cracked, or fractured, dry or wet, but there is essentially no moving fluid. By this invention, thermal energy is transferred from the hot rocks to a relatively cool liquid which flows from a manifold at the surface down into the hot rocks and then through one or more of a plurality of remotely separated heat-conducting pipe loops which join together at the bottom of a riser through which the heated liquid returns to the surface."

[0009] Drilling The configuration is not discussed in detail with complex patterns or arrangements of heat recovery conduits. strata for transporting fluid through an arrangement for heat recovery from Drilling Another drawback is that Drilling This is seen in the positioning of manifolds above the surface rather than within a network of holes drilled into the ground.

[0010] In U.S. Patent No. 6,668,554, issued December 30, 2003, Brown teaches a fracturing process for forming fracture zones in hot, dry rock. Supercritical CO2 is used as the working fluid to generate geothermal strata There is no fluid communication in the closed loop, and in the closed loop, there is an interconnected section in the fluid communication between the inlet well and the outlet well, where the working fluid strata In the Brown configuration, strata itself indiscriminately communicates with the inlet and outlet wells. This is further demonstrated by Brown's teaching that: "Finally, the hot dry rock circulation system will be completed by drilling two or more production wells to intersect the reservoir near each end of the elongated reservoir region as defined by the 'cloud' of microseismic event locations that define the geometry of the fractured hot dry rock reservoir. All wells will be properly completed, again using gaseous carbon dioxide, with casing to the surface and then removal of drilling fluids and other water-based materials."

[0011] From this progression, the use of casing is identified as the intersection of wells, but not with each other as in a closed loop, but rather strata It is identified as the intersection with the artificial reservoir within the

[0012] U.S. Patent No. 10,260,778 to Sonju, issued April 16, 2019, discloses a geothermal plant. There are teachings in the patent regarding the specific requirements for the configuration of the production section in a specific alignment with respect to the concentric inlet / outlet well arrangement. The disclosure is based on the idea of ​​using the production section during or after drilling. Drilling The report does not provide any guidance on the possible directions for coordinating the use of thermal zones or for interconnecting zones to utilize thermal zones without restrictions.

[0013] U.S. Patent No. 10,527,026 to Muir et al., issued January 7, 2020, teaches a closed-loop heat recovery arrangement for transferring heat from a well casing into a fluid. The text states: "Embodiments disclosed herein relate to methods and apparatus for the production of power from impermeable geological resources through the use of a closed loop design, in which a fluid is pumped through a closed loop well. strata The heat is transferred through the well casing to the fluid.” "As described in the Background section above, typical hydrothermal systems as well as closed loop systems have focused on extracting heat from permeable geological resources where fractures or porosity arise naturally or through stimulation. In contrast, the embodiments disclosed herein are capable of efficiently and effectively extracting heat from low permeability rocks, such as rocks in the plastic zone. strata is used advantageously by passing a fluid through the resource without direct contact between the fluid and the rock, whereby heat is transferred directly from the rock, through the well casing and into the fluid.” "The closed-loop geothermal heat exchange system then strata Based on the determined temperature profile and the determined heat replenishment profile, strata The installation of the closed loop geothermal heat exchange system can include drilling, casing, perforating, bonding, expanding the uncased well wall with fractures, sealing the uncaseable well wall, and other steps associated with the drilling process and installing a well loop therein, as known to those skilled in the art. Installation can, in some embodiments, include: strata In some embodiments, the installation may include disposing a heat exchange zone of the closed loop well system within the plastic zone or the brittle-ductile transition zone of the well. strata "The method may include, or may additionally include, disposing a heat exchange zone of the closed loop well system within the brittle zone of the well, and stimulating the brittle zone adjacent the heat exchange zone."

[0014] The text provides general teachings on sealing, but: Drilling The text states: "According to some embodiments, the methods for generating geothermal energy described herein may include sections of a well that are not cased with metal pipe, but instead, such sections of the well are sealed with a hardened sealant." strataThe well walls in such sections may be defined by the boundaries of such hardened sealant, which in some embodiments may result in larger well diameters in such sections, in some cases much larger than in the metal cased sections of such wells."

[0015] This reference mirrors the teachings of Shulman above, but does not address well intersections, the absence of casing and / or liners, or any other design considerations to accommodate thermal gradient patterns. Drilling No guidance is given for geometric variations in the arrangement of the heat recovery sections of the layout. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] U.S. Patent No. 6,247,313 [Patent Document 2] U.S. Patent No. 5,515,679 [Patent Document 3] U.S. Patent No. 6,668,554 [Patent Document 4] U.S. Patent No. 10,260,778 [Patent Document 5] U.S. Patent No. 10,527,026 Summary of the Invention [Problem to be solved by the invention]

[0017] Specific measures adapted to the limitations of existing equipment and methods for recovering thermal energy Drilling Allows the user to adapt to anomalies in gradient patterns, as opposed to being constrained by design Drilling It would be desirable to have a method of forming the configuration.

[0018] The method of the invention disclosed herein below improves upon the limitations mentioned and provides a heat-producing strataIt offers previously unseen freedom to efficiently capture thermal energy from within. [Means for solving the problem]

[0019] One object of one embodiment of the present invention is to provide a heat-producing facility for recovering thermal energy therefrom for subsequent use. strata The present invention provides an improved method for configuring wells and well systems in a geological repository.

[0020] Another object of one embodiment of the present invention is to provide a heat-producing strata During Drilling The present invention provides a method for constructing a A well having an inlet well and an outlet well is strata and independently drilling into the communicating between the inlet well and the outlet well during drilling to intersect to form a continuous well having an interconnected section between the inlet well and the outlet well, the interconnected section being strata having a predefined angular configuration with respect to the inlet well and the outlet well within the conditioning at least the interconnected sections to facilitate heat recovery by working fluid flow therethrough without casing or liner material in the interconnected sections; Includes.

[0021] The adjusting step is accomplished by at least one of a sequenced combination of continuous drilling, discontinuous drilling, drilling periods, post-drilling, and drilling of at least one of the inlet wells and the outlet wells.

[0022] More specifically, the adjusting step includes: strata The method may include introducing at least one composition, unit operation, and combinations thereof that is not naturally present in the system.

[0023] To improve the effectiveness of the method, the adjustment operations may be dynamically changed in response to signaling data from at least one of the inlet well drilling operations and the outlet well drilling operations.

[0024] Depending on the specific situation, the unit operations include controlling the temperature of the drilling fluid and strata pre-cooling the rock face in the well and cooling the drilling rig; strata Formed from excavations in Drilling and modifying the pore space of the

[0025] The change in pore space is due to the strata Fluid ingress or strata The methods can include activating the pore space for subsequent processing to render the pore space impermeable to the flow of working fluid into the cavity, sealing the pore space during drilling in a continuous operation, sealing the pore space during drilling in a discontinuous operation, and combinations thereof.

[0026] Changes in operational adjustment steps may also be based on signaling data from signaling between the inlet and outlet wells.

[0027] Optionally, the further unit motion is relative to the longitudinal axis of the interconnected section. strata In order to improve heat recovery by the working fluid during strata and forming a conduit in fluid communication with the well. The conduit can have a termination and a location of the conduit in the interconnected section can be in thermal contact with an adjacent conduit in an adjacent interconnected section of another well. The conduit can include natural buoyancy-driven convection that expands the effective radius of the heat collecting interconnected section to increase the overall heat transfer from the rock volume.

[0028] The conduit may be a fracture, a single hole, a secondary section, or multiple radial holes extending radially from the interconnect section.

[0029] When arranged in a vertical configuration, the conduits act as convection cells where natural buoyancy-driven convection currents expand the effective radius of the heat collecting interconnect section. The conduits are typically 0.5 inches (12.7 mm) or larger in diameter and may be 8.5 inches (215.9 mm) or equal to the diameter of the interconnect section itself.

[0030] As another option, the conduits of an interconnect section may be connected in fluid communication with adjacent conduits of adjacent interconnect sections of different wells.

[0031] It is a further object of one embodiment of the present invention to provide a heat-producing device through the circulation of a fluid therethrough. strata To provide a well configuration suitable for recovering thermal energy from a well, the well configuration comprising: The entrance well, An exit well, in fluid communication with the inlet well and the outlet well; strata an interconnect section disposed within the heat productive area of ​​the a selectively operable auxiliary section in selective fluid circulation communication with the interconnect section for storing heated fluid; a debris section in fluid communication with at least one of the inlet well, the outlet well, and the interconnecting section for collecting debris from the well, a debris section, the outlet well being at least one of concentric with the inlet well and between 5° and 175° to the inlet well, and an interconnecting section being between 5° and 355° to the inlet well; a conversion device connected to the well to form a closed loop and collect the thermal energy recovered from the fluid for conversion; Equipped with.

[0032] In one embodiment, the auxiliary section includes a selectively operable valve for allowing the stored heated fluid circulation to access the interconnected section and may further include a selectively operable outlet in fluid communication with at least one of the conversion device and the adjacent well configuration.

[0033] The configuration may be a multiple well configuration in concentric and spaced apart relationship, a multiple well configuration in spaced apart laterally offset parallel planar relationship, and may further include at least one of a common inlet well and a common outlet well.

[0034] In collecting thermal energy, interconnected sections are utilized, and the configuration can provide a plurality of interconnected sections in fluid communication with the inlet and outlet wells having a plurality of spaced apart arrays of interconnected sections in a predefined pattern.

[0035] It is yet a further object of one embodiment of the present invention to provide a heat-producing device capable of generating heat through the circulation of a fluid therethrough. strata To provide a method for forming a well configuration suitable for recovering thermal energy from a thermal energy source, the method comprising: Inlet and outlet wells strata independently drilling at predefined locations within the Between the inlet and outlet wells strata In strata cross-drilling from an inlet well and an outlet well to form an interconnected section in a predefined thermally productive area of ​​a location, the outlet well being at least one of: concentric with the inlet well; at an angle between 5° and 175° relative to the inlet well; and the interconnected section being at an angle between 5° and 355° relative to the inlet well; forming a selectively operable auxiliary section in selective fluid circulation communication with said interconnected section for storing heated fluid; forming a debris section in fluid communication with at least one of the inlet well, the outlet well, and the interconnection section for collecting debris from a well; providing a conversion device in communication with the well to form a closed loop and collect thermal energy recovered from the fluid for conversion; Includes.

[0036] For intersection drilling, the step of drilling independently from the inlet and outlet wells to form an interconnected section between the inlet and outlet wells is performed by electromagnetic signal transmission.

[0037] Electromagnetic signal transmission devices are utilized for signal transmission and are selectively positioned at combinations of predefined locations of the inlet wells, outlet wells, debris sections, and interconnect sections.

[0038] The device can be operated in a predefined sequence.

[0039] Additionally, the method includes signaling the ongoing well with signaling from an adjacent previously formed well.

[0040] The method uses geothermal heat having a temperature of 40° C. or more. strata It is well suited for the recovery of thermal energy from

[0041] strata For efficiency and flexibility of deployment within the interconnected sections, circulation of fluid within the interconnected sections can be performed without casings and liners.

[0042] A plurality of interconnected sections in an embodiment can be in fluid communication with the inlet and outlet wells, the configuration having a plurality of spaced apart arrays of interconnected sections in a predefined pattern.

[0043] Optionally, there may be a step of selectively circulating fluid as a slipstream from one array to an inlet point of a remote second array before discharging from an outlet well common to all arrays, in which the slipstream preheats the fluid from the inlet well before circulating it into the remote second array.

[0044] Slipstreams can also be distributed to adjacent well configurations for thermal augmentation of adjacent wells.

[0045] Having thus generally described the invention, reference is now made to the accompanying drawings in which a preferred embodiment is illustrated. [Brief description of the drawings]

[0046] [Figure 1] FIG. 2 is a schematic diagram of a closed loop energy recovery arrangement. [Diagram 2] FIG. 2 is a coordinate system diagram illustrating possible locations of interconnected sections or groups of sections within the volume of the formation for recovering thermal energy therefrom. [Diagram 3] 1 is a flow chart depicting the steps involved in forming a wellbore configuration by drilling an intersection of at least two points. [Figure 4] FIG. 13 is a cross-sectional view of a variant of the borehole. [Diagram 5] FIG. 5 is a side view of FIG. [Figure 6] FIG. 6 is an alternative embodiment of FIG. 5. [Figure 7] FIG. 1 illustrates an embodiment of a wellbore configuration. [Figure 8] FIG. 13 is an alternative embodiment of a wellbore configuration. [Figure 9] FIG. 13 is a diagram of a further alternative embodiment of a wellbore configuration. [Figure 10] FIG. 13 is a diagram of a further alternative embodiment of a wellbore configuration. [Figure 11] FIG. 13 is a diagram of a further alternative embodiment of a wellbore configuration. [Figure 12] FIG. 13 is a diagram of a further alternative embodiment of a wellbore configuration. [Figure 13] 1 is a schematic diagram of a system of wellbore configurations within an earth formation; [Figure 14] FIG. 1 is a schematic diagram of a network of segmented wellbore configurations. [Figure 15] FIG. 1 is a schematic diagram of a well system illustrating a debris field. [Figure 16] FIG. 1 is a schematic diagram of modularly stacked wells. [Figure 16A] FIG. 17 is an alternative embodiment of FIG. 16. [Figure 17]FIG. 1 is a schematic diagram of a well system with interconnections between sub-sections. [Figure 18] FIG. 1 is a schematic diagram of a network of well systems integrated with an electric power grid. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0047] Like numbers used in the figures refer to like elements.

[0048] Referring to Figure 1, strata 1, a schematic diagram of a closed-loop well system 10 disposed within a reservoir 12 is shown. The system 10 includes an inlet well 14, an interconnected well section 16, and an outlet well 18 in closed-loop fluid communication with an energy processing device 20 positioned at the earth's surface S. The outlet well may be co-located with the inlet well at the device 20, or in an alternative connection may be located remotely as indicated by dashed line 22. strata A working fluid is circulated within the system 10 to absorb thermal energy from within 12 .

[0049] For efficiency, the interconnected well section 16 is not cased or lined and does not include other pipes or associated mechanical equipment. The outlet well 18 and the inlet well 16 may be cased or otherwise constructed to conform to accepted practices known to those skilled in the art. Any debris generated in the use of the equipment may be collected in section 19.

[0050] The energy processing device 20 can process the energy for other uses, indicated broadly by the numeral 24, store it at 26, or pass it on to a power grid 28, which can optionally include solar power generation devices 30 and / or wind power generation devices 32 in any suitable combination.

[0051] Heat-producing strataWith regard to the spatial orientation of the wells in the wells, reference can be made to Figure 2. In the figure, elements have been removed for clarity, but it should be understood that the figure is intended to convey that the arrangement of the interconnect sections 16 may be with respect to at least one of the planes of the inlet wells 14 and the outlet wells 18.

[0052] In the figures, the interconnected well sections 16 may be positioned at any angle in any of the planes (XY), (X-(-Y)), ((-X)-Y), ((-X)-(-Y)), (XZ), (X-(-Z)), (Z-(-X)), ((-X)-(-Z)), (ZY), (Z-(-Y)), ((-Z)-(-Y)), and ((-Z)-Y), and may be arranged to have X, Y, and Z coordinates with respect to an intersecting planar arrangement. For purposes of illustration, the positive x-axis will represent the inlet well 14. The wells may be arranged at any angle α or β without interfering with the operation of the well 14. This applies equally to the outlet well 18. The inlet well 14 and the outlet well 18 communicate with the surface S of the earth as referenced with respect to FIG. 1.

[0053] Any number of interconnect sections 16 may be disposed within the space illustrated. Other well configurations are illustrated in the previous figures. The quantities and spatial locations are strata The thermal gradient of the temperature gradient is dependent on the temperature gradient of the

[0054] Advantageously, observing that drilling an intersection between the inlet well 14 and the outlet well 16 by independent drilling operations to form the interconnected section 18 without liners, casings, etc., within the interconnected section with coordinated drilling operations, provides configuration freedom for maximum recovery of thermal energy.

[0055] FIG. 3 shows the crossover through the interconnect section formed. strata2 illustrates an example of steps involved in sensor ranging an inlet well and an outlet well in a well system. While the example refers to interconnect sections, it will be understood that the methodology relates to forming multiple interconnect sections in any pattern as discussed with respect to FIG. 2. Individual interconnect sections may have sensors in communication therebetween to communicate with subsequent interconnect sections or strata The present invention is fully applicable to guide the excavation of formations in adjacent systems within the geological record.

[0056] By providing interconnection between the well, inlet, outlet, and interconnection sections, trajectory drift is minimized to facilitate accurate intersecting of the well being drilled. Sensors may also be utilized in the debris capture section 19, but are not shown and will not be described in greater detail herein below.

[0057] Referring now to FIG. 4, a cross section of interconnect section 16 is strata Extending from section 16 are: strata 12. The conduits 34 may be in fluid communication with the interiors 36 of the sections 16 or may be sealed voids without fluid communication with the interiors 36. It has been found that the conduits 34 are useful in improving the heat recovery capabilities of the interconnected sections when working fluid is circulated therethrough and during periods of quiescence. The positioning and amount of radial extension to maximize heat recovery without structural / mechanical compromise of the sections 16 can be determined by: strata The characteristics of the conduit are dictated by the depth of the tunnel. Where appropriate, pre-existing cracks, fissures, fractures or permeable zones may be encountered and used to act as conduits. This may be done during excavation of section 16.

[0058] 5 shows an example where the conduits 34 are generally arranged in a spiral pattern, with the black dots representing those extending outward from the plane and the x dots representing extensions on the opposite surface extending away from the plane. This is by way of example only, and the pattern is confirmed from the gradient data, among other closely related parameters.

[0059] FIG. 6 shows a plurality of sections 16 strata 12. In this example, extensions 34 of adjacent sections can be positioned closely together to fill a given area 38 with the extensions to effectively increase the volume of the gradient from which thermal energy can be harvested. The conduits 34 act as convective cells for buoyancy-driven flow that directs thermal energy to the interior 34 of the section 16. The extensions can be positioned for adjacent positioning or can interdigitate with other conduits 34.

[0060] As a further embodiment, the individual sections 16 may be connected by conduits 34 , the connections being generally represented by the numeral 40 . In this way, the arrangement has a ladder-like appearance when viewed in perspective.

[0061] Now, turning to the possible well configurations, Fig. 7 shows that strata 12 and generally indicated by the numeral 42.

[0062] In this arrangement, the inlet well 14 is in fluid communication with a main inlet hub well 44, which is connected to each of the interconnected sections 16. Suitable valve devices (not shown, but generally designated by the numeral 46) may be incorporated into some or all of the loop sections 16 for redirection and other control of the fluid flow.

[0063] The arrangement 42 also includes a main outlet hub well 48 connected in a manner similar to that shown for the main inlet hub well 46 with similar valving features (not shown).

[0064] Within this structure, each loop section 16 can operate as a single unit to recover thermal energy.

[0065] As an operational alternative, the flow of working fluid within the arrangement 42 can be circulated in a generally spiral pattern throughout the entire arrangement with sequencing of periods of rest to allow for maximum heat recovery. Such flexibility allows for connection to, for example, the energy processing device 20. This facilitates on-demand power as energy is converted to power, overcoming limitations associated with baseload power peak dispatch issues.

[0066] 8 illustrates a further embodiment of a well configuration designated by the numeral 50. The overall shape is saddle-shaped, with the interconnecting loop sections being arched and adjacent to one another. The inlet wells 14 can be connected to each of the loop sections 16 in a hub or manifold arrangement 52, or valved at 54 for selective operation. Similarly, the outlets 18 can be connected in the same manner.

[0067] FIG. 9 illustrates yet another possible variation of the generally inverted parabolic shape.

[0068] 10 illustrates another well system configuration in which the inlets 14 may be separate from a distant point in the configuration or may be joined at 56. Similarly, the outlets 18 may be joined at 58. To be co-located, the outlets 58 and inlets 56 may be extended to be in geographic proximity.

[0069] 11 illustrates a generally conical configuration in which the exit well 18 may be at the bottom of the configuration or at the top as shown by the dotted line. The lower portions of the loop sections 16 may be connected together or may be separate.

[0070] 12 illustrates yet another configuration, generally in the shape of a whisk. In this embodiment, a loop of sections 16 may have concentric inlets 14 and outlets 18, with fluid from the inlet flowing in the direction of arrows 62 and the outlet flowing at 64. This arrangement allows for the outer strata Among the 12, and within the composition strata The heat in volume 66 is "harvested" strata A larger volume of the inlet and outlet flow is possible. One advantage with this configuration is that all crossings occur in a single drilled hole or "mother hole", simplifying electromagnetic signal transfer, which can even be accomplished passively or by placing an anchoring device in the mother hole. Another advantage is that only one vertical hole is required to accommodate both the inlet and outlet flow rates.

[0071] Turning now to Figure 13, generally designated by the numeral 68, Drilling Sectors of the system are depicted diagrammatically. Sector 68 is the heat-producing strata 12, and to maximize the coverage of the gradient, Drilling The positioning of the configuration is in a predefined zone. In this example, the sectors 68 provide for an overlapping and spaced apart arrangement of loop sections 16 sharing a common inlet well 14 and a common outlet well 18.

[0072] Depending on the parameters, the circulation of the fluid may follow the patterns shown at A through F. In this manner, at least a portion of the heated fluid from the top loop section 70 may preheat the fluid entering the bottom loop section 72. Alternatively, each of the loop sections 70 and 72 may operate independently.

[0073] As with the remaining configurations, the annular configuration 80 may receive heated fluid from the outlets 18 of the stacked arrangements 70, 72 as indicated by dotted line 74, or may simply have an independent inlet well 14 as indicated by dashed line 76.

[0074] The whisk configuration can have a separate inlet well 14 and outlet well 18 positioned at the bottom, or the inlet well can be common to that of the annular configuration as indicated by numeral 78.

[0075] Finally, the saddle configuration may include a common exit well with the annular configuration 80 .

[0076] It will be understood that all inlet wells 14 and outlet wells 18 extend to the surface or to the conversion device 20 (FIG. 1) for operation. In FIG. 13, the wells 14, 18 are cut away for clarity of illustration.

[0077] Sector 68 is Drilling The configurations, common and independent combinations, are merely exemplary. With interconnecting directional drilling, coordinated motion, and sensor-guided drilling, any pattern or configuration can be synchronized to utilize even the most irregular, heterogeneous, multi-zone gradient distributions. All of these features, when combined with the fact that the technology does not involve piping liners or other mechanical devices within the heat recovery interconnection sections, rapidly remove the geometric limitations for configurations and therefore allow drilling into any rock mass. strata This allows mining of any gradient within

[0078] Figure 14 shows strata 12 is another example of a well arrangement 82 for recovering thermal energy from a particular volume of the well 12. In this example, the debris section 19 can include a sensor 84 to transmit information regarding debris accretion. In this manner, the working fluid can be altered in composition to incorporate chemical additives to reduce / repair compromised areas of the well system. The arrangement of interconnected sections 16 may be arranged in a spaced apart array as shown to recover thermal energy.

[0079] Additionally, as illustrated in FIG. 15, the auxiliary section 86 may be in fluid communication with the respective section 16 to which it is attached and may incorporate a valve mechanism 88 to allow selective operation. The auxiliary section 88 may be used to store heated working fluid that may be selectively used as a thermal driver in the deployment for the well system in this example, or through a suitable interconnection to another well system (not shown in this figure). As illustrated, the auxiliary section 86 may be positioned in a coplanar arrangement with the section to which it is attached, or in an orthogonal plane as indicated by the dotted line in the figure. Suitable variations thereto are envisioned depending on the gradient characteristics.

[0080] FIG. 16 and FIG. 16A are strata 1 illustrates well systems 82 grouped together in different angular arrangements within a well borehole. In the grouped configuration, the systems 82 include: strata The system 82 is modularized within a particular volume of the system 82, thus allowing for convenient overall co-location of the inlet wells 14 and the outlet wells 18 in a small footprint. Within a module, the inlet wells 14 and the outlet wells may be common to individual well systems or may be common to all modules in the system 82.

[0081] FIG. 17 provides the possibility of interconnecting subsections 86 between adjacent wells at 90 or of supplementing heat from one outlet 18 to the inlet 14 of an adjacent well.

[0082] In FIG. 18, the network depicted is intended to convey the characteristic that energy generated within any well system 82 can be taken directly for use elsewhere through energy generating devices 20 associated with systems 82, linked from one system 82 to another 82, as indicated by numeral 96, or further grouped as indicated by numeral 98 for ultimate use on the power grid 28 to provide power on demand regardless of the quantity demand. [Industrial Applicability]

[0083] This technology is one of the Drilling Possible applications include formation, drilling, and energy recovery areas. [Explanation of symbols]

[0084] 3 Supply hole 4 Return Hole 5 Heat absorption holes 6 Fracture zones, interconnected sections 10. Closed Loop Well System 12 Heat-producing strata 14 Entrance well, entrance 16 Interconnecting well section, interconnecting section, loop section, loop of sections 18 Exit well, exit 19 Debris Capture Section 20 Energy processing devices, conversion devices, energy generating devices 22 Dotted Line 24 Other Uses 26 Storage 28 Power grid 30 Solar power generation devices 32 Wind power generation devices 34 Conduit, extension 36 Internal 38 areas 40 Connections 42 Circular well configuration 44 Main entrance hub well 46 Valve device, main inlet hub well 48 Main outlet hub well 50 Well configuration 52 Manifold arrangement 54 Valve Control 56 Entrance 58 Exit 62 Arrow 64 Arrow 66 strata volume 68 sectors 70 Loop Section, Placement 72 Loop section, arrangement 74 Dotted Line 76 Chain Line 78 Entrance Well 80 Circular Configuration 82 Well arrangement, well system 84 Sensors 86 Auxiliary Section 88 Valve mechanism, auxiliary section 90 possibilities 96 Consolidated 98 Grouping

Claims

1. 1. A method for constructing a wellbore in a thermally productive formation, comprising: drilling entry wells and exit wells into the formation; drilling between the entrance wells and the exit wells to form a continuous geothermal recovery well having a first interconnecting section and a second interconnecting section between the entrance wells and the exit wells, the first interconnecting section and the second interconnecting section having a predefined angular configuration within the formation relative to the entrance wells and the exit wells, the first interconnecting section including a first lateral drilling extending from a downhole end of the entrance well to a downhole junction, the second interconnecting section including a second lateral drilling extending from a downhole end of the exit well to the downhole junction, the second lateral drilling being disposed at a depth greater than a depth of the first lateral drilling; conditioning at least the first and second interconnect sections by sealing the first and second interconnect sections to facilitate heat recovery by working fluid flow therethrough, the first and second interconnect sections being at least partially open hole; A method comprising:

2. The method of claim 1 , wherein adjusting comprises introducing a composition or performing a unit operation that is not native to the formation.

3. The method of claim 1 , further comprising dynamically varying the adjusting step in response to signaling data obtained during drilling of the entry well and the exit well.

4. 3. The method of claim 2, wherein the unit operations include controlling a temperature of a drilling fluid, pre-cooling a rock face in the formation being drilled, and sealing pore space in the formation.

5. 5. The method of claim 4, wherein sealing the pore space includes at least one of: i) making the pore space impermeable to ingress of formation fluids into at least a portion of the first interconnected section and the second interconnected section or egress of the working fluid into the formation; ii) sealing the pore space during drilling in a continuous operation; or iii) sealing the pore space during drilling in a discontinuous operation.

6. The method of claim 4 , further comprising selecting a change based on signaling data from signaling between the entry well and the exit well.

7. 5. The method of claim 4, wherein the unit operations include forming a conduit in the formation relative to longitudinal axes of the first interconnected section and the second interconnected section, in fluid communication with the formation for enhancing heat recovery by the working fluid.

8. The method of claim 7 , wherein the conduit has a terminal end.

9. The method of claim 8 , wherein the conduit comprises at least one of a radial hole section, an induced fracture, an induced crack, or an induced fissure.

10. 9. The method of claim 8, further comprising: enhancing heat recovery by the conduit by flowing a portion of the working fluid into the conduit and allowing the portion of the working fluid in the conduit to heat a portion of the working fluid inside the first interconnected section and the second interconnected section.

11. 10. The method of claim 9, further comprising positioning a radial hole section of the second interconnect section in thermal contact with an adjacent radial hole section of the first interconnect section of another well.

12. 10. The method of claim 9, wherein the continuous geothermal recovery well includes a borehole that is U-shaped in side view, and further includes connecting radial hole sections of an interconnected section to fluidly communicate with adjacent radial hole sections of adjacent interconnected sections of another well.

13. 2. The method of claim 1, further comprising positioning the first interconnect section and the second interconnect section within the formation relative to a plane of the entrance borehole and a plane of the exit borehole, wherein the plane of the first phase interconnect section lies in a plane selected from the group including orthogonal, acute, obtuse, flush, and parallel to the plane of the entrance borehole, and the plane of the second phase interconnect section lies in a plane selected from the group including orthogonal, acute, obtuse, flush, and parallel to the plane of the exit borehole.

14. 2. The method of claim 1, comprising configuring the continuous geothermal recovery well to flow the working fluid from the entrance well to the downhole junction and from the downhole junction to the exit well, the second lateral well being downwardly inclined and the downhole junction being at a depth greater than a depth of the downhole end of the exit well.

15. 2. The method of claim 1, wherein at least one of the first interconnected section and the second interconnected section further comprises a debris section extending from the downhole junction to a download end and configured to accumulate debris of the geothermal recovery well.

16. 2. The method of claim 1 , wherein the first interconnection section and the second interconnection section include: i) a first group of lateral drillings extending from a downhole end of the entrance well to a plurality of downhole junctions; and ii) a second group of lateral drillings extending from a downhole end of the exit well to the plurality of downhole junctions, each of the first group of lateral drillings connected to each of the second group of lateral drillings at a respective junction of the plurality of downhole junctions, and the regulating step includes flowing the working fluid from the entrance well to the plurality of downhole junctions and from the plurality of downhole junctions to the exit well.

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