DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This is in response to Applicant’s arguments and amendments filed on 04/15/2026 amending Claims 1 – 3, 5, 8, 10 – 12, 14, and 17. Claims 1 - 18 are examined.
Claim Objections
Claims 5 and 14 are objected to because of the following informalities:
Claim 5, ll. 1 – 2 “a turbine section” is believed to be in error for --[[a]] the turbine section-- because Claim 1, l. 2 previously recited ‘a turbine section’.
Claim 14, ll. 1 – 2 “a turbine section” is believed to be in error for --[[a]] the turbine section-- because Claim 1, l. 2 previously recited ‘a turbine section’.
Appropriate correction is required.
Claim Rejections - 35 USC § 103
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1 – 9 are rejected under 35 U.S.C. 103 as being unpatentable over Callas (8,220,268) in view of Cunha et al. (5,634,766).
Regarding Claim 1, Callas teaches, in the sole figure, the invention as claimed, including a method of operating a turbomachine (10 – gas turbine engine – Col. 2, ll. 55 - 65), the method comprising: directing a flow of ammonia vapor (in line 48, Col. 5, ll. 10 - 20) to one or more hot gas path components (46 - Col. 5, ll. 40 – 45 “high temperature exhaust”) of the turbomachine, whereby heat is transferred to the ammonia vapor from the one or more hot gas path components (Col. 5, ll. 40 – 45 “the fuel may then be directed through heat exchanger 46 to absorb additional heat from the high temperature exhaust exiting turbine section 16.”); cracking the ammonia vapor by the heat from the one or more hot gas path components (Col. 5, ll. 45 – 50 “After exiting heat exchanger 46, the fuel may be directed through catalytic cracker 50 for further conditioning before entering combustion chamber 26”), whereby a hydrogen gas and a nitrogen gas are produced (cracking ammonia inherently produced hydrogen gas and a nitrogen gas per the chemical equation 2 NH3 [Wingdings font/0xE0] N2 + 3 H2); flowing the ammonia vapor across a catalyst (inside 50, i.e., Col. 5, ll. 45 – 50 “… catalytic cracker 50”), and flowing (Col. 5, ll. 45 – 50) the hydrogen gas (H2) produced by cracking the ammonia vapor to a combustor (26) of the turbomachine (10).
Callas is silent on said one or more hot gas path components being located in a turbine section of said turbomachine and silent on said catalyst positioned downstream of the turbine section with respect to the flow of ammonia vapor. Callas further teaches, in Col. 4, ll. 45 – 50, that the one or more hot gas path components, i.e., heat exchanger (46), could have a different location such as between the low pressure turbine (16a) and the recuperator (34).
Cunha teaches, in Figs. 1 – 26, a similar turbomachine (10) having one or more hot gas path components, in this case a plurality of first stage nozzle heat exchangers (54 - Col. 7, ll. 55 – 60, Col. 8, ll. 5 – 10, and Col. 9, ll. 30 – 40), located in a turbine section (20) of the turbomachine (10). As shown in Fig. 4 and discussed in Col. 10, ll. 15 – 35, a cooling gas flowed into inlet (82) then through a plurality of cooling channels inside the first stage nozzle before the now heated cooling gas flowed out through outlet (84).
It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify Callas with the one or more hot gas path components, in this case a plurality of first stage nozzle heat exchangers, located in the turbine section, taught by Cunha, because all the claimed elements, i.e., the turbomachine/gas turbine including one or more hot gas path components, a combustor, a catalytic cracker for ammonia, and a hot gas path component being a heat exchanger inside a first stage nozzle in the turbine section, were known in the art, and one skilled in the art could have substituted the hot gas path component being a first stage nozzle heat exchanger in a turbine section, taught by Cunha, for the hot gas path component (heat exchanger 46), taught by Callas, with no change in their respective functions, to yield predictable results, i.e., the ammonia vapor flowing into, through, and out of the first stage nozzle would have facilitated increasing the operational life of the first stage nozzle by cooling, i.e., absorbing heat, said first stage nozzle during operation of the turbomachine/gas turbine. Absorbing heat from the first stage nozzle would have facilitated cracking the ammonia vapor into hydrogen gas and nitrogen gas per the chemical equation 2 NH3 [Wingdings font/0xE0] N2 + 3 H2, because ammonic cracking was an endothermic process, i.e., energy usually in the form of heat was required to drive the process. KSR, 550 U.S. 398 (2007), 82 USPQ2d at 1395; MPEP 2143(B). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, that in the combination of Callas, i.v., Cunha, said catalyst would have been positioned downstream of the turbine section with respect to the flow of ammonia vapor because heated ammonia vapor would have flowed out of said one or more hot gas path components, i.e., plurality of first stage nozzle heat exchangers, located in said turbine section, through an ammonia line to the catalyst (inside 50, i.e., Callas Col. 5, ll. 45 – 50 “… catalytic cracker 50”) where the heated ammonia vapor would have been cracked into hydrogen gas that flowed out of the catalytic cracker (50) and into said combustor (26) of said turbomachine (10).
Re Claim 2, Callas, i.v., Cunha, teaches the invention as claimed and as discussed above, including wherein [The following is the designed and intended use of an ammonia catalytic cracker.] the ammonia vapor is cracked by interaction with the catalyst and by the heat from the one or more hot gas path components.
Re Claim 3, Callas, i.v., Cunha, teaches the invention as claimed and as discussed above, including wherein the ammonia vapor is heated by the one or more hot gas path components in said turbine section before flowing the ammonia vapor across the catalyst, refer to the Claim 1 rejection above.
Re Claim 4, Callas, i.v., Cunha, teaches the invention as claimed and as discussed above, and Callas further teaches, in sole figure, providing a flow of liquid ammonia to a cooling air system (38) of the turbomachine (10) and generating the flow of ammonia vapor from the liquid ammonia in the cooling air system (38) of the turbomachine.
Re Claim 5, Callas, i.v., Cunha, teaches the invention as claimed and as discussed above, including, wherein the cooling air system (38 - Callas), a turbine section, i.e., plurality of first stage nozzle heat exchangers, of the turbomachine (10 - Callas), and the combustor (26 - Callas) of the turbomachine form an ammonia vapor circuit, refer to the Claim 1 rejection above.
Re Claim 6, Callas, i.v., Cunha, teaches the invention as claimed and as discussed above, and Callas further teaches, in sole figure, further comprising flowing the nitrogen gas produced by cracking the ammonia vapor (inside 50) to the combustor (26) of the turbomachine. As discussed in Claim 1 above, cracking ammonia inherently produced hydrogen gas and a nitrogen gas per the chemical equation 2 NH3 [Wingdings font/0xE0] N2 + 3 H2 and both the hydrogen gas and the nitrogen gas flowed into the combustor (26) of the turbomachine.
Re Claim 7, Callas, i.v., Cunha, teaches the invention as claimed and as discussed above, including wherein directing the flow of ammonia vapor to the one or more hot gas path components (i.e., plurality of first stage nozzle heat exchangers) of the turbomachine (10) comprises flowing the ammonia vapor through a cooling circuit (ammonia vapor flow path inside the plurality of first stage nozzle heat exchangers) within at least one of the one or more hot gas path components of the turbomachine (10). As discussed in Claim 1 above, Cunha taught, in Col. 10, ll. 15 – 35, a cooling gas flowed into inlet (82) then through a plurality of cooling channels inside the first stage nozzle before the now heated cooling gas flowed out through outlet (84).
Re Claims 8 and 9, Callas, i.v., Cunha, teaches the invention as claimed and as discussed above, including wherein (Claim 8) the one or more hot gas path components of the turbomachine comprises a nozzle in the turbine section of the turbomachine and (Claim 9) wherein the nozzle is a first stage nozzle (Cunha - Col. 9, ll. 30 – 40), refer to the Claim 1 rejection above.
Claims 10 – 18 are rejected under 35 U.S.C. 103 as being unpatentable over Callas (8,220,268) in view of Ito et al. (2024/0011435A1) in view of Cunha et al. (5,634,766).
Regarding Claim 10, Callas teaches, in the sole figure, the invention as claimed, including a turbomachine (10 – gas turbine engine – Col. 2, ll. 55 - 65), comprising: one or more hot gas path components (46 - Col. 5, ll. 40 – 45 “high temperature exhaust”); a combustor (26); directing a flow of ammonia vapor (in line 48, Col. 5, ll. 10 - 20) to one or more hot gas path components (46 - Col. 5, ll. 40 – 45 “high temperature exhaust”) of the turbomachine, whereby heat is transferred to the ammonia vapor from the one or more hot gas path components (Col. 5, ll. 40 – 45 “the fuel may then be directed through heat exchanger 46 to absorb additional heat from the high temperature exhaust exiting turbine section 16.”); cracking the ammonia vapor by the heat from the one or more hot gas path components (Col. 5, ll. 45 – 50 “After exiting heat exchanger 46, the fuel may be directed through catalytic cracker 50 for further conditioning before entering combustion chamber 26”), whereby a hydrogen gas and a nitrogen gas are produced (cracking ammonia inherently produced hydrogen gas and a nitrogen gas per the chemical equation 2 NH3 [Wingdings font/0xE0] N2 + 3 H2); flowing the ammonia vapor across a catalyst (inside 50, i.e., Col. 5, ll. 45 – 50 “… catalytic cracker 50”), and flowing (Col. 5, ll. 45 – 50) the hydrogen gas (H2) produced by cracking the ammonia vapor to a combustor (26) of the turbomachine (10).
Callas is silent on a controller, the controller configured for: directing a flow…; cracking the ammonia; and flowing the hydrogen gas.
Ito teaches, in Figs. 1 – 6, a similar turbomachine (1) having a controller (31) configured for: directing a flow of ammonia (14-44-46) to a catalytic cracker (16) where the ammonia was cracked into hydrogen gas and a nitrogen gas that flowed to a combustor (13) of the turbomachine (1). Ito teaches, in Para. [0010], “…the gas turbine system may include a controller configured to control the first flow rate control valve so that ammonia is supplied from the ammonia tank to the ammonia cracking catalyst during an operation of the gas turbine system”. Ito teaches, in Para. [0042], “The controller 31 controls the whole gas turbine system 1”. Ito teaches, in Para. [0035], “The ammonia cracking catalyst 16 cracks ammonia into hydrogen and nitrogen. Specifically, the cracked gas contains hydrogen and nitrogen”.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify Callas with the controller, taught by Ito, because all the claimed elements, i.e., the turbomachine/gas turbine including one or more hot gas path components, a combustor, a catalytic cracker for ammonia, and the controller that controls the whole turbomachine/gas turbine system, were known in the art, in combination each one of the components would perform the same function as it did separately, and one skilled in the art could have combined the elements as claimed by known methods, with no change in their respective functions, to yield predictable results, i.e., integrating the controller would have facilitated controlling the whole turbomachine/gas turbine system. KSR, 550 U.S. 398 (2007), 82 USPQ2d at 1395; MPEP 2143(A).
Callas, i.v., Ito, is silent on said one or more hot gas path components being located in a turbine section and silent on said catalyst being positioned downstream of the turbine section with respect to the flow of ammonia vapor. Callas further teaches, in Col. 4, ll. 45 – 50, that the one or more hot gas path components, i.e., heat exchanger (46), could have a different location such as between the low pressure turbine (16a) and the recuperator (34).
Cunha teaches, in Figs. 1 – 26, a similar turbomachine (10) having one or more hot gas path components, in this case a plurality of first stage nozzle heat exchangers (54 - Col. 7, ll. 55 – 60, Col. 8, ll. 5 – 10, and Col. 9, ll. 30 – 40), located in a turbine section (20) of the turbomachine (10). As shown in Fig. 4 and discussed in Col. 10, ll. 15 – 35, a cooling gas flowed into inlet (82) then through a plurality of cooling channels inside the first stage nozzle before the now heated cooling gas flowed out through outlet (84).
It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify Callas, i.v., Ito, with the one or more hot gas path components, in this case a plurality of first stage nozzle heat exchangers, located in the turbine section, taught by Cunha, because all the claimed elements, i.e., the turbomachine/gas turbine including one or more hot gas path components, a combustor, a catalytic cracker for ammonia, and a hot gas path component being a heat exchanger inside a first stage nozzle in the turbine section, were known in the art, and one skilled in the art could have substituted the hot gas path component being a first stage nozzle heat exchanger in a turbine section, taught by Cunha, for the hot gas path component (heat exchanger 46), taught by Callas, i.v., Ito, with no change in their respective functions, to yield predictable results, i.e., the ammonia vapor flowing into, through, and out of the first stage nozzle would have facilitated increasing the operational life of the first stage nozzle by cooling, i.e., absorbing heat, said first stage nozzle during operation of the turbomachine/gas turbine. Absorbing heat from the first stage nozzle would have facilitated cracking the ammonia vapor into hydrogen gas and nitrogen gas per the chemical equation 2 NH3 [Wingdings font/0xE0] N2 + 3 H2, because ammonic cracking was an endothermic process, i.e., energy usually in the form of heat was required to drive the process. KSR, 550 U.S. 398 (2007), 82 USPQ2d at 1395; MPEP 2143(B). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, that in the combination of Callas, i.v., Ito and Cunha, said catalyst would have been positioned downstream of the turbine section with respect to the flow of ammonia vapor because heated ammonia vapor would have flowed out of said one or more hot gas path components, i.e., plurality of first stage nozzle heat exchangers, located in said turbine section, through an ammonia line to the catalyst (inside 50, i.e., Callas Col. 5, ll. 45 – 50 “… catalytic cracker 50”) where the heated ammonia vapor would have been cracked into hydrogen gas that flowed out of the catalytic cracker (50) and into said combustor (26) of said turbomachine (10).
Re Claim 11, Callas, i.v., Ito and Cunha, teaches the invention as claimed and as discussed above, including wherein [The following is the designed and intended use of an ammonia catalytic cracker.] the ammonia vapor is cracked by interaction with the catalyst and by the heat from the one or more hot gas path components.
Re Claim 12, Callas, i.v., Ito and Cunha, teaches the invention as claimed and as discussed above, including wherein the ammonia vapor is heated by the one or more hot gas path components in said turbine section before flowing the ammonia vapor across the catalyst, refer to the Claim 10 rejection above.
Re Claim 13, Callas, i.v., Ito and Cunha, teaches the invention as claimed and as discussed above, and Callas further teaches, in sole figure, further comprising a cooling air system (38) of the turbomachine (10) for providing a flow of liquid ammonia (Col. 5, ll. 10 - 20) to the cooling air system (38) of the turbomachine and generating the flow of ammonia vapor (42) from the liquid ammonia in the cooling air system (38) of the turbomachine
Callas, i.v., Ito and Cunha, as discussed above, is silent on said controller is further configured for said providing a flow of liquid ammonia to the cooling air system.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, that the controller of Callas, i.v., Ito and Cunha, could have been configured for said providing a flow of liquid ammonia to the cooling air system because all the claimed elements, i.e., the turbomachine/gas turbine including one or more hot gas path components, a combustor, a catalytic cracker for ammonia, and the controller that controls the whole turbomachine/gas turbine system, were known in the art, in combination each one of the components would perform the same function as it did separately, and one skilled in the art could have combined the elements as claimed by known methods, with no change in their respective functions, to yield predictable results, i.e., integrating the controller would have facilitated controlling the whole turbomachine/gas turbine system which would have included providing a flow of liquid ammonia to the cooling air system, e.g., opening a valve to allow liquid ammonia to flow into and through said cooling air system. KSR, 550 U.S. 398 (2007), 82 USPQ2d at 1395; MPEP 2143(A).
Re Claim 14, Callas, i.v., Ito and Cunha, teaches the invention as claimed and as discussed above, including, wherein the cooling air system (38 - Callas), a turbine section, i.e., plurality of first stage nozzle heat exchangers, of the turbomachine (10 - Callas), and the combustor (26 - Callas) of the turbomachine form an ammonia vapor circuit, refer to the Claim 10 rejection above.
Re Claim 15, Callas, i.v., Ito and Cunha, teaches the invention as claimed and as discussed above, and Callas further teaches, in sole figure, further comprising flowing the nitrogen gas produced by cracking the ammonia vapor (inside 50) to the combustor (26) of the turbomachine. As discussed in Claim 10 above, cracking ammonia inherently produced hydrogen gas and a nitrogen gas per the chemical equation 2 NH3 [Wingdings font/0xE0] N2 + 3 H2 and both the hydrogen gas and the nitrogen gas flowed into the combustor (26) of the turbomachine. Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, that the controller of Callas, i.v., Ito and Cunha, would have been further configured for flowing the nitrogen gas produced by cracking the ammonia vapor to the combustor of the turbomachine for the reason discussed above.
Re Claim 16, Callas, i.v., Ito and Cunha, teaches the invention as claimed and as discussed above, including wherein directing the flow of ammonia vapor to the one or more hot gas path components (i.e., plurality of first stage nozzle heat exchangers) of the turbomachine (10) comprises flowing the ammonia vapor through a cooling circuit (ammonia vapor flow path inside the plurality of first stage nozzle heat exchangers) within at least one of the one or more hot gas path components of the turbomachine (10). As discussed in Claim 10 above, Cunha taught, in Col. 10, ll. 15 – 35, a cooling gas flowed into inlet (82) then through a plurality of cooling channels inside the first stage nozzle before the now heated cooling gas flowed out through outlet (84).
Re Claims 17 and 18, Callas, i.v., Ito and Cunha, teaches the invention as claimed and as discussed above, including wherein (Claim 17) the one or more hot gas path components of the turbomachine comprises a nozzle in the turbine section of the turbomachine and (Claim 18) wherein the nozzle is a first stage nozzle (Cunha - Col. 9, ll. 30 – 40), refer to the Claim 10 rejection above.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Response to Arguments
Applicant's arguments filed 04/15/2026 have been fully considered and to the extent possible have been addressed in the rejections above, at the appropriate locations.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LORNE E MEADE whose telephone number is (571)270-7570. The examiner can normally be reached Monday - Friday 8-5 EST.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Phutthiwat Wongwian can be reached at 571-270-5426. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/LORNE E MEADE/Primary Examiner, Art Unit 3741
Prosecution Insights