DETAILED ACTION
Notice of Pre-AIA or AIA Status
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
2. A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 1/23/2026 has been entered.
Status of the Claims
3. The status of the claims as filed in the reply dated 1/23/2026 are as follows:
Claims 1, 10, 11, 14, and 19 are amended,
Claims 1-20 are currently pending.
Claim Rejections - 35 USC § 112
4. The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
5. Claims 12 and 14-18 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 12 recites “a distance of at least 1 m” in line 2, which is indefinite as it is not clear what that distance is between. For examples, is the distance between particles? For examining purposes the distance will in interpreted as from the mouth of the wellborn.
Claim 14 recites “target location” in lines 4 and 4-5, which is unclear as to whether this location is being positively recited. For examining purposes the location will be interpreted as being positively recited.
Claims 15-18 are rejected as they depend on claim 14.
Claim Rejections - 35 USC § 102
6. The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
7. Claim(s) 1-4 and 6-10 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Amerman et al (U.S. Patent No. 6,672,371, “Amerman”, previously cited).
Regarding claim 1, Amerman discloses a pumpable suspension for placement of a consolidated particle sheath (fig 18C), comprising:
a mixture (356) comprising a suspended thermal reach enhancement (TRE) solid and a high apparent viscosity carrier fluid (col 3, line 63-col 4, line 5);
wherein the TRE solid is in the form of a plurality of TRE particles and the high apparent viscosity carrier fluid suspends the particles throughout the fluid (col 3, line 63-col 4, line 5);
wherein the high apparent viscosity carrier fluid has a composition that allows a change in pH or temperature change to change physical properties of the mixture in situ to thereby reduce viscosity and thereby allow the particles to settle via gravity at a target location to form a settled particle sheath within an annular space of a wellbore (col 12, lines 23-25, as a temperature change would affect pH); and
wherein the carrier fluid and the TRE particles have a composition that allows, upon the change of the physical property of the mixture, consolidation of the settled particle sheath to form a high-thermal conductivity compacted sheath within the annular space of a wellbore (fig 18C).
Regarding claim 2, Amerman further discloses wherein consolidation comprises hydraulic consolidation the TRE particles (fig 18C).
Regarding claim 3, Amerman further discloses wherein the plurality of TRE particles comprise zinc (col 3, line 63-col 4, line 5).
Regarding claim 4, Amerman further discloses wherein the compacted sheath has a thermal conductivity of greater than 1.5 W/mK (col 12, lines 41-51).
Regarding claim 6, Amerman further discloses wherein plurality of the TRE particles make up between 10 vol% and 75 vol% of the total suspension (50% to 80%, col 12, line 15).
Regarding claim 7, Amerman further discloses wherein he high apparent viscosity carrier fluid comprises a quantity of water (col 3, line 63-col 4, line 5).
Regarding claim 8, Amerman further discloses wherein the high apparent viscosity carrier fluid further comprises a viscosity agent of a guar gum (col 4, lines 6-8).
Regarding claim 9, Amerman further discloses wherein the high apparent viscosity carrier fluid has a composition that allows reducing the viscosity with a shear force (via by mixing, see col 12, lines 23-25).
Regarding claim 10, Amerman further discloses wherein the change in pH changes the physical properties (temperature) of the mixture (as a change in pH would coincide with a change in temperature).
Claim Rejections - 35 USC § 103
8. The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
9. Claim(s) 11-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Amerman as applied to claim 1 above, and further in view of Kumar et al. (U.S. Patent Publication No. 2014/0158354, “Kumar”, previously cited).
Regarding claim 11, Amerman discloses all previous claim limitations. However, Amerman does not explicitly disclose wherein the high apparent viscosity carrier fluid has a dynamic viscosity, before the addition of temperature, of at least 5,000 centipoise (cP), and a dynamic viscosity, after the addition of temperature, of no more than 1,000 cP. Kumar, however, discloses a suspension wherein a high apparent viscosity carrier fluid has a dynamic viscosity, before the addition of temperature, of at least 5,000 centipoise (cP), and a dynamic viscosity, after the addition of temperature, of no more than 1,000 cP (¶0122). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Amerman It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Amerman to provide the viscosities of Kumar in order to ensure optimal viscosity before and after settling thus ensuring the optimal structure for heat transfer.
Regarding claim 12, Amerman discloses all previous claim limitations. However, Amerman does not explicitly disclose wherein the plurality of TRE particles have a size that allows settling of the TRE particles a distance of at least 1m within 24 hours after reducing the viscosity. Kumar, however, discloses a suspension wherein the plurality of TRE particles have a size that allows settling of the TRE particles a distance of at least 1m within 24 hours after reducing the viscosity (¶0150). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Amerman to provide the particle size of Kumar in order to ensure the optimal thermal conductivity after settling.
Regarding claim 13, Amerman discloses all previous claim limitations. However, Amerman does not explicitly disclose wherein the settled particle sheath has a final porosity of equal or less than 80% and/or is consolidated to have a permeability of equal or less than 0.01 Darcy. Kumar, however, discloses a suspension wherein the settled particle sheath is consolidated to have a permeability of equal or less than 0.01 Darcy (¶0215). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Amerman to provide the porosity of Kumar in order to provide the optimal thermal conductivity after settling.
10. Claim(s) 14-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Amerman et al (U.S. Patent No. 6,672,371, “Amerman”, previously cited) in view of Wildig et al. (U.S. Patent No. 9,310,103, “Wildig”).
Regarding claim 14, Amerman discloses a system configured to transfer heat from a geological formation to a heat harvester casing (fig 18C), comprising:
a heat harvester casing (358) disposed in a wellbore that descends substantially vertically from a topside location to a target location in a geological formation (fig 18C);
a thermal reach enhancement (TRE) structure (350) at the target location extending from the wellborn distally into the geological formation (fig 18C) and comprising a first high thermal k material (“solid”, col 3, line 53-col 4, line 5);
wherein the TRE structure is a man-made and/or naturally occurring fissure containing the first high thermal k material (as the TRE structure would have to be either man-made or natural);
wherein the TRE structure has a proximal mouth portion at the wellbore (see annotated fig 18C below);
a high-thermal conductivity compacted sheath (356) comprising multiple sheath segments (see annotated fig 18C below) along a vertical length of the high-thermal conductivity compacted sheath, that is thermally coupled to (a) an outer surface of the casing and substantially vertically extends along some of the length of the target location in an annular space of the wellbore, and (b) the mouth portion of the TRE structure to thereby form a continuous heat transfer path from the geological formation at the target location through the TRE structure and compacted sheath to the casing (fig 18C); and
wherein the compacted sheath has a thermal conductivity of between about 1.5 w/mK and 50 W/mK (col 12, lines 41-51).
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However, Amerman does not explicitly disclose wherein the target location is at a depth of between 150 m to 20,000 m. Wildig, however, discloses a geothermal system (fig 2) wherein a heat harvester casing (23) has a target location at a depth of 250 m (col 3, lines 26-30). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Amerman to have the target location be 250 m such as taught by Wildig in order to optimize the depth of the geothermal heat transfer of the system.
Regarding claim 15, the combination of Amerman and Wildig discloses all previous claim limitations. Amerman further discloses wherein the geological formation at the target location is capable of having has a geostatic temperature of between 120 °C and 600 °C. A recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus satisfying the structural limitations of the claims, as is the case here.
Regarding claim 16, the combination of Amerman and Wildig discloses all previous claim limitations. Amerman further discloses wherein the first high thermal k (“solid”, col 3, line 53-col 4, line 5) material of the proximal mouth portion of the TRE structure (see annotated fig 18C above) is flush to the annular space of the wellbore.
Regarding claim 17, the combination of Amerman and Wildig discloses all previous claim limitations. Amerman further discloses wherein the compacted sheath extends substantially vertically along between 10% and 70% of the target location (as it extends the length of the target location).
Regarding claim 18, the combination of Amerman and Wildig discloses all previous claim limitations. Amerman further discloses wherein the compacted sheath has a thermal conductivity that is equal of the thermal conductivity of the TRE structure (as they comprise the same structure).
11. Claim(s) 19-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Amerman et al (U.S. Patent No. 6,672,371, “Amerman”, previously cited) in view of Kumar et al. (U.S. Patent Publication No. 2014/0158354, “Kumar”, previously cited).
Regarding claim 19, Amerman discloses a system configured to transfer heat from a geological formation to a heat harvester casing (fig 18C), comprising:
a heat harvester casing (358) disposed in a wellbore that descends substantially vertically from a topside location to a target location in a geological formation (fig 18C);
a high-thermal conductivity (356) compacted sheath comprising multiple sheath segments along a vertical length of the high-thermal conductivity compacted sheath (see annotated fig 18C), that is thermally coupled to (a) an outer surface of the casing and substantially vertically extends along some of the length of the target location in an annular space of the wellbore, and (b) the target location in the geological formation to thereby form a continuous heat transfer path from the target location via the high-thermal conductivity compacted sheath to the casing; and
wherein the compacted sheath has a thermal conductivity of between about 1.5 w/mK and 50 W/mK ((col 12, lines 41-51).
However, Amerman does not explicitly disclose wherein the high-thermal conductivity compacted sheath has a permeability of equal or less than 0.01 Darcy. Kumar, however, discloses a suspension wherein a high-thermal conductivity compacted sheath has a permeability of equal or less than 0.01 Darcy (¶0215). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Amerman to provide the porosity of Kumar in order to provide the optimal thermal conductivity after settling.
Regarding claim 20, the combination of Amerman and Kumar discloses all previous claim limitations. Amerman further discloses wherein the geological formation at the target location is capable of having has a geostatic temperature of between 120 °C and 600 °C. A recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus satisfying the structural limitations of the claims, as is the case here.
Allowable Subject Matter
12. Claim 5 objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Response to Arguments
13. Applicant's arguments filed 1/23/2026 have been fully considered but they are not persuasive.
Applicant argues (page 8) that Amerman does not teach the limitation of amended claim 1. The Examiner respectfully disagrees; the limitations of claim 1 are met by Amerman as outlined in the rejection above.
Applicant argues (page 8) that Amerman does not teach the limitations of amended claim 14. However, the limitations of claims are met by Amerman and newly cited Wildig as outlined in the rejection above.
Applicant argues (pages 8-9) that Amerman does not teach the limitations of amended claim 19. However, as outlined above in the rejection the combination of Amerman and Kumar do teach the limitations of claim 19.
Applicant argues (page 9) that Kumar, specifically in paragraph [0122], does not teach a suspension wherein a high apparent viscosity carrier fluid has a dynamic viscosity, before the addition of temperature, of at least 5,000 centipoise (cP), and a dynamic viscosity, after the addition of temperature, of no more than 1,000 cP. However, Kumar, in paragraph [0122], teaches a suspension that has a dynamic viscosity before the addition of temperature of less than 30,000 centipoise (cP), and a dynamic viscosity after the addition of temperature of 20-50 cP (see ¶0102 and ¶0185), thus meeting the required limitations.
Applicant argues (page 9) that there is no technical explanation provided as to how Kumar's viscosities could possibly ensure optimal thermal conductivity after settling. In addition, and as already noted earlier, Amerman is concerned with permanently maintaining particles suspended to avoid issues with settling of a conventional suspension. Any reduction in viscosity would render Amerman' s system inoperable. However, as now explained in the rejection above, it would be obvious to one of ordinary skill in the art for Amerman to provide the viscosities of Kumar in order to ensure optimal viscosity before and after settling thus ensuring the optimal structure for heat transfer. Further, there is nothing in either reference to suggest that the viscosities of Kumar would render the system of Amerman inoperable as the sheath needs to be initially viscous enough to be pumped and then solid enough to allow the particles to be set in place.
Applicant argues (page 10) that rejection recites " ... Kumar, however, discloses a suspension wherein the plurality of TRE particles have a size that allows settling of the TRE particles a distance of at least 1 m within 24 hours after reducing the viscosity (¶0l50)... " Such argument is a mis-reading of the reference as Kumar's fluid is a shear-thinning fluid that increases viscosity. The Examiner respectfully disagrees; firstly it is unclear as to what the distance of 1 m is in relation too, see the 35 USC § 112 above. Secondly, Kumar teaches the fluid being solid within two hours and thus teaches settling of TRE particles.
Applicant argues (page 10) that Kumar's particles are not TRE particles but inorganic settling materials such as cements. See Kumar [0154]. On a finer note, Kumar is concerned with lost circulation materials, that are entirely inconsistent with TRE particles. However, the particles of Kumar must absorb and release heat and thus are considered TRE particles.
Applicant argues (page 10) that the rejection states " ... Kumar, however, discloses a suspension wherein the settled particle sheath is consolidated to have a permeability of equal or less than 0.0I Darcy (¶02 l 5)... " Such statement is entirely incorrect. Instead, Kumar teaches that " ... Silica sols with particle sizes ranging between about 4 nanometers and about I00 nanometers have been found to have an excellent injectivity in formations with permeabilities as low as 1 mD to 50 mD... " Formation permeability is completely different from permeability of a consolidated sheath. The Examiner respectfully disagrees; substances decrease in permeability when consolidated and thus the consolidated sheath would still be less than 0.01 Darcy.
Applicant argues (pages 10-11) that the multiple sheath segments of Amerman pointed out in the Office Action are arbitrarily selected and do not correspond to any process or structure found in Amerman. More significantly, the Examiner's identification of the topside end of the wellbore as allegedly being the 'proximal mouth portion/mouth portion' is entirely inconsistent with that term as used in the claims and the specification: The proximal mouth portion is the terminal portion of a TRE structure that extends from the wellbore into the geological formation. The Examiner respectfully disagrees; there is nothing in the claim language that inhibits the interpretation of the sections as outlined in the rejection above.
Applicant argues (page 11) that while Applicant agrees that Amerman teaches gel materials, there is no indication of any phase change material in Amerman, let alone a phase change material that would allow for a reduction of viscosity. However, there is no requirement for a phase change material within the claims.
Conclusion
14. Any inquiry concerning this communication or earlier communications from the examiner should be directed to HARRY E ARANT whose telephone number is (571)272-1105. The examiner can normally be reached Monday-Friday 10-6 ET.
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/HARRY E ARANT/Primary Examiner, Art Unit 3763