Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This action in response to remarks and amendments filed 11/3/2025.
Claim Rejections - 35 USC § 112
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.
Claim 14 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 14 recites “power generated in step (e) comprises electrical power and step (f) comprises providing at least a portion of the electrical power to at least one of the hydrogen production system and the natural gas liquefaction system”; however, step (f) is explicitly about using mechanical coupling for the natural gas liquefaction system so it is unclear how this would relate to the electrical power production. For the purpose of examination, this limitation is understood that the steam turbine system produces electrical power which has to be used within the system.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are: natural gas liquefaction system in claims 1 and 24, understood to be any system which includes a compressor that liquefies natural gas;
power generating system in claims 1 and 24, understood to be a power generating system that includes at minimum a gas turbine,
hydrogen production system in claims 1 and 24, understood to be a system which uses a reformer or equivalent,
air separation unit in claim 9, understood to be a system that uses distillation to separate air.
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
Closed loop refrigeration system in claim 23 is not considered to invoke 35 USC 112(f), as it is a closed loop refrigeration system has a specific understood structure in the art.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claim(s) 1, 3-4, 12-17, 21-23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt et al (US PG Pub 20220065526), hereinafter referred to as Van der Walt and further in view of Minta (US PG Pub 20100107684), hereinafter referred to as Minta and Byfield (US PG Pub 20120067080), hereinafter referred to as Byfield.
With respect to claim 1, Van der Walt teaches a method (Figure 1) comprising:
(a) at least partially liquefying a natural gas feed stream in a natural gas liquefaction system to form an LNG stream (natural gas from pipeline 102 is liquefied in 110, paragraph 104), the natural gas liquefaction system including a first and a second refrigeration compressor to compress refrigerant (there can be multiple refrigerant compressors in the liquefaction system, paragraph 104);
(b) separating the LNG stream into a vapor stream and an LNG product stream (boil off gas is produced and separate from the LNG stream, paragraph 105);
(c) passing at least a portion of the vapor stream to a hydrogen production system (boil-off gas can be sent to hydrogen production, paragraph 105)
(d) reacting at least a portion of the vapor stream in the hydrogen production system to form a hydrogen containing stream and a first C02-enriched stream (in the hydrogen production, hydrogen and carbon dioxide are formed, paragraph 110, where hydrogen is passed to a gas turbine 122 and carbon dioxide is sent for capture 128, paragraph 111, 117);
(e) generating power in a power generating system using at least a portion of the hydrogen containing stream and at least a portion of a first steam stream from the hydrogen production system (power is generated in the gas turbine 122 using the hydrogen and in a steam system, where the gas turbine can be used to drive compressors, paragraph 104 and the steam can be used for a generator to produce electricity, paragraph 115),
(f) driving a refrigeration compressor by mechanically coupling first gas turbine of the power generated in step (e) to a refrigeration compressor) (the compressor of the liquefaction unit receives power either mechanically or electrically from the gas turbine, paragraph 104).
Van Der Walt does not teach that the compressors of the liquefaction system include a first refrigeration compressor to compress refrigerant and provide compressed refrigerant, a second refrigeration compressor to further compress the compressed refrigerant and provide further compressed refrigerant and a third refrigeration compressor to compress propane to be used to cool the further compressed refrigerant and driving the second refrigeration compressor and the third refrigeration compressor by mechanically coupling a first gas turbine to the second refrigeration compressor and the third refrigeration compressor of the natural gas liquefaction system, and driving the first refrigeration compressor by mechanically coupling a second gas turbine to the first refrigeration compressor.
Byfield teaches (Figure 2) teaches a refrigeration compression arrangement of a natural gas liquefaction system (paragraph 21) where there are two gas turbines (1st driver 60 and 2nd driver 68, paragraphs, 41, 59-60) where the first driver is used for providing energy to a propane compressor (44, paragraph 57) and a compressor which compresses a different refrigerant which has already been compressed (MPMR and/or HPMR, paragraph 57) and a second driver is used to compressor a the refrigerant upstream of the MPMR and HPRM (low pressure first stage of compressor 12, paragraph 60). The turbines are connected to the compressors by shafts (58, 66, paragraphs 59-60).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have provided as the liquefaction system of Van Der Walt a configuration as in Byfield where there are at least three compressors, one which compresses the first refrigerant and is powered by a gas turbine via a shaft (second turbine and mechanical coupling) and a second compressor which further compresses the refrigerant as well as a propane compressor for compressing propane refrigerant which are together driven by another gas turbine via a shaft since it has been shown that combining prior art elements to yield predictable results is obvious whereby providing a natural gas liquefaction system with a propane pre-cooling system as well as a refrigerant compression system with multiple drivers would provide what would be common knowledge in the art of the ability to provide the necessary refrigeration for liquefying the natural gas while also providing the ability to drive the refrigerant cycles using suitable methods.
Van der Walt does not teach that the vapor stream separated from the LNG stream is a flash gas stream.
Minta teaches that after liquefaction that the final LNG is flashed and separated into a flash vapor stream (16) which is used as fuel to power the compressor units of the refrigeration system and the LNG stream (15) (paragraph 24).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have prior to storage to have flashed the LNG stream of Van der Walt and used that stream for power generation as well (which in Van der Walt would mean using it as part of the hydrogen production, which is what Van der Walt does with all vapor natural gas containing streams) since it has been shown that combining prior art elements to yield predictable results is obvious whereby flashing the stream and separating the flash would increase the amount of fuel for use in energy generation while reducing the pressure and temperature of the LNG which would provide the predictable result of reducing boil off and flash in storage by bringing the pressure down prior to storage which would have the benefit that would be recognized in the art of providing further control to the power generation by producing controlling how much flash gas is sent for power generation.
Van der Walt does not teach the first gas turbine is the gas turbine that was from the power generated in step (e).
Van der Walt (as shown above) teaches that the gas turbine is mechanically coupled to the at least one compressor within the liquefaction unit (paragraph 132). As modified, there are two gas turbines used to provide mechanical coupling to the compression, and thus one of the gas turbines would be the one . Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have had the gas turbine that is used to provide power to second refrigeration compressor and the third refrigeration compressor of the natural gas liquefaction system of Van der Walt as modified since it has been shown that choosing from a finite number of identified predictable solutions with a reasonable expectation of success is obvious whereby as there are two gas turbines available and both gas turbines are needed for powering compressors having the one for the second refrigeration compressor and third refrigeration compressor be from the power generating system as one having ordinary skill in the art would recognize that as there are only two gas turbines, there would be a reasonable expectation of success in the one from the power generating system being suitable for powering the second and third refrigeration compressors.
With respect to claim 3, Van der Walt as modified teaches wherein the hydrogen containing stream is at least 80 mol % hydrogen (the hydrogen provided as fuel can be as high as 85 percent, paragraph 111).
With respect to claim 4, Van der Walt teaches as modified further comprising: (g) separating a second CO2-enriched stream from the natural gas feed stream before performing step (a) (carbon dioxide is removed at 104 and sent to sequestration 130, paragraph 98); and (h) combining the first C02-enriched stream and the second C02-enriched stream for form a combined CO2 stream (carbon dioxide from 104 is sent to 130 as is carbon dioxide from capture which comes from hydrogen production, paragraph 117, see Figure 1 arrows).
With respect to claim 12, Van der Walt as modified teaches wherein step (e) further comprises generating power in a power generating system using the hydrogen containing stream to drive at least one gas turbine (hydrogen is used for a gas turbine, and then waste heat is recovered which heats steam for a generator to produce electricity, paragraph 115).
Van der Walt does not explicitly teach that the energy generated by first steam is used in a steam turbine.
Examiner takes official notice that when driving a compressor with steam it would have been obvious to a person having ordinary skill in the art at the time the invention was filed for that power generating system to have been a steam turbine as it is a known and reliable way of producing energy using steam. This official notice has not been timely traversed and as such it is considered admitted prior art.
Van der Walt does not teach the using the hydrogen containing stream to generate power in the first and the second gas turbine; however, this is a mere duplication of parts. Van der Walt teaches the use of the hydrogen stream to power a gas turbine and as modified has two gas turbines present, but does not teach how the other gas turbine is operated. As there is already one present in the hydrogen production system, and as modified there are two overall, it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have when using two gas turbines in Van der Walt for both of them to have generated power using the hydrogen containing stream as using two gas turbines instead of one powered by hydrogen is a mere duplication of parts that has no patentable significance as it does not provide a new an unexpected result as all it does is provided the expected result of producing power from hydrogen.
With respect to claim 13, Van der Walt as modified teaches wherein the power generated in step e further comprises electrical power (the steam stream can be used to generate energy, paragraph 115).
With respect to claim 14, Van der Walt teaches wherein the power generated in step (e) comprises electrical power (the steam generates electricity) and step (f) comprises providing at least a portion of the electrical power to at least one of the hydrogen production system and the natural gas liquefaction system (the electricity can be used in other parts of the facility 100, paragraph 115, which parts comprise the hydrogen production system and the natural gas liquefaction system, and thus using electricity somewhere else within 100 would meet the limitation as claimed).
With respect to claim 15, Van der Walt as modified teaches wherein the power generated in step (e) comprises electrical power and the method further comprises: (k) exporting at least a portion of the electrical power to a process that is external to the natural gas liquefaction system, the hydrogen production system, and the power generating system (some of the electrical power generated in the system can be exported to the grid, paragraph 115).
With respect to claim 16, Van der Walt as modified teaches wherein step (e) further comprises generating power in the power generating system using the hydrogen containing stream, the first steam stream, and at least one methane-containing stream (the natural gas stream can be sent to at least one of the fuel gas condition skid and the hydrogen production, paragraph 103, which as modified would be the flash gas, which means that since it is at least one, then both conditions can exist such that the flash gas would pass to the fuel gas condition skid and the gas turbine would receive both the hydrogen and the hydrogen production, and the steam stream is also used in the power generating system per claim 1).
With respect to claim 17, Van der Walt as modified teaches wherein the at least one methane-containing stream comprises the flash vapor stream (the flash vapor stream is the stream sent form the natural gas as modified).
With respect to claim 21, Van der Walt as modified teaches: (n) using heat generated from at least one of the hydrogen production system and the power generating system to provide heat duty for drier unit (waste heat recovered from the gas turbine can be used to provide heat to the dehydration unit, paragraph 114), the drier until being adapted to separate moisture from a natural gas feed stream for the natural gas liquefaction system (the dehydration unit is for removing water from the natural gas feed stream, paragraph 100).
With respect to claim 22, Van der Walt as modified teaches: (o) dividing the natural gas feed stream into a first portion and a second portion (in the heavies removal unit 108, the natural gas is separated into a gas stream which is sent for liquefaction and a condensate stream, paragraphs 102, 104), performing step (a) on the first portion of the natural gas feed stream (the gas stream is sent for liquefaction), and combining the second portion of the natural gas feed stream with the flash vapor stream before performing step (d) (a portion of the second portion is sent as part of the flash gas stream to hydrogen production as boil off as seen in the figure, paragraph 102, where it would be mixed with the flash vapor stream as modified).
With respect to claim 23, Van der Walt as modified teaches wherein step (a) comprises at least partially liquefying the natural gas feed stream in the natural gas liquefaction system to form the LNG stream, the natural gas liquefaction system including a closed loop refrigeration system having the second compressor (as modified the second compressor is part of a closed loop refrigeration cycle of propane).
Claim(s) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Byfield and further in view of Walther (US PG Pub 20100175425), hereinafter referred to as Walther.
With respect to claim 2, Van der Walt as modified does not teach wherein the flash vapor stream is at least 50 mol % methane. It should be noted, that as the stream is an LNG stream it is likely and all but inherent that any flash gas stream would be over 90% methane, but this is not explicit in the teachings of Minta or Van der Walt.
Walther teaches that in an LGN process that the flash gas stream (212) from the flash vas vessel (236) (paragraph 73) is 91.8% methane (Table, page 10, stream 212).
It would therefore have been obvious to a person having ordinary skill in the art at the time the invention was filed to have based on the teaching of Walther to have when producing a flash gas stream in Van der Walt as modified for that stream to have been 91.8% methane as applicant appears to have placed no criticality on the claimed range (the stream has to be only at least 50% methane, paragraph 11) and since it has been held that “[i]n the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists.” In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). One having ordinary skill in the art would recognize from this teaching by Walther that it would be obvious that a flash gas stream formed of an LNG stream would be well over 50% methane.
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta and further in view of Pan et al. (US PG Pub 20110126451), hereinafter referred to as Pan.
With respect to claim 5, Van der Walt does not teach (i) using refrigeration duty from the natural gas liquefaction system and the combined C02-enriched stream.
Pan teaches that carbon dioxide separated from natural gas can be liquefied in the same refrigeration system used to cool the natural gas is also used to liquefy the carbon dioxide for transport to a market location as a product as an option differing from sequestration (paragraph 23).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have instead of sequestering the combined stream of carbon dioxide using the sequestration compression method to have based on the teaching of Pan to have used the liquefaction system of the liquefaction unit of Van der Walt to have combined and then liquefied the combined carbon dioxide stream (which were previously combined at sequestration) for transport to market as a product since it has been shown that a simple substitution of one known element for another to yield predictable results is obvious whereby providing the liquefaction instead of sequestration of carbon dioxide streams produced in Van der Walt would provide the predictable results of producing another useful product which can be transported for use and sold as opposed to sequestered.
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Byfield and further in view of Tamhankar et al. (US PG Pub 20180148330).
With respect to claim 6, Van der Walt as modified does not teach wherein step (d) further comprises reacting at least a portion of the flash vapor stream and an ambient air stream in the hydrogen production system to form the hydrogen containing stream and the first CO2-enriched stream.
Tamhankar teaches that in the typical combustion process in a methane former that ambient air is drawn into the methane reformer for combustion (paragraph 25). Further, steam is used in this reaction using waste heat from the process (paragraph 27).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have reacted the flash vapor stream of Van der Walt as modified in the stream reformer with an ambient air stream based on the teaching of Tamhankar which ultimately produces the hydrogen and the carbon dioxide and generated steam using waste heat from the process for use in the reforming since it has been shown that combining prior art elements to yield predictable results is obvious whereby using an ambient air stream would provide the predictable result of necessary oxygen to the system for combustion needed for the reforming process and the necessary steam for the process as well.
Claim(s) 7-8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Byfield and further in view of Tamhankar et al. (US PG Pub 20180148330), hereinafter referred to as Tamhankar and Qian et al. (US PG Pub 20220074655), hereinafter referred to as Qian.
With respect to claims 7-8, Van der Walt as modified does not teach wherein step (d) further comprises reacting at least a portion of the flash vapor stream and an oxygen containing stream in the hydrogen production system to form the hydrogen containing stream, the first C02-enriched stream, the first steam stream wherein the oxygen containing stream is ambient air. It should be noted that the reformer is a steam reformer (paragraph 7), which means that steam has to be generated in the process for use and some form of oxygen stream would be used as well.
Tamhankar teaches that in the typical combustion process in a methane former that ambient air is drawn into the methane reformer for combustion (paragraph 25). Further, steam is used in this reaction using waste heat from the process (paragraph 27).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have reacted the flash vapor stream of Van der Walt as modified in the stream reformer with an ambient air stream and generated steam using waste heat from the process for use in the reforming since it has been shown that combining prior art elements to yield predictable results is obvious whereby using an ambient air stream would provide the predictable result of necessary oxygen to the system for combustion needed for the reforming process and the necessary steam for the process as well.
Van der Walt as modified does not teach that the reaction results in a waste nitrogen stream.
Qian teaches that nitrogen is produced in reforming methods and that nitrogen removal can be done downstream of the reformer (paragraphs 1-3). Removal of nitrogen results in a waste nitrogen stream (paragraph 7).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have based on the teaching of Qian to have provided nitrogen removal downstream the reformer (which would produce a waste nitrogen stream) as part of the hydrogen production system of Van der Walt as modified since it has been shown that combining prior art elements to yield predictable results is obvious whereby separating any nitrogen produced in the reforming would provide the predictable results of removing any nitrogen impurities in the produced hydrogen stream.
Claim(s) 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Byfield/Tamhanker/Qian and further in view of Turney et al. (US PG Pub 20210331917), hereinafter referred to as Turney.
With respect to claim 9, Van der Walt as modified does not teach generating passing an ambient air stream through an air separation unit to produce the oxygen obtaining stream and a nitrogen stream.
Turney teaches that a feed air stream (418, which can be considered the ambient air stream, as it would ultimately come from an ambient air stream) is sent to a nitrogen generator (421, which as seen in Figure 3 is a distillation column, paragraph 16-17, and thus an air separation unit) and then the oxygen is mixed with the hydrogen generator process stream (which is methane) to produce hydrogen (Paragraph 145-146, Clm 11).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have based on the teaching of Turney to have when reforming the methane stream in Van der Walt to have provided an air separation unit from an ambient air stream which produces an oxygen stream and a nitrogen stream and then used the oxygen in the reforming process as a partial oxidation reformer as the first part of the reformer along with the flash gas since it has been shown that combining prior art elements to yield predictable results is obvious whereby using an air separation unit to produce oxygen and then combining that with the flash gas stream would provide the predictable result of utilizing a known reforming method for utilizing methane for hydrogen production that is known to be faster than steam reforming.
Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Byfield/Tamhanker/Qian/Turner and further in view of Davidian (US PG Pub 20150253075), hereinafter referred to as Davidian.
With respect to claim 10, Van der Walt teahces wherein step (e) further comprises generating power using the hydrogen containing stream and the first steam stream (the steam and hydrogen are used per claim 1).
Van Der Walt does not teach that at least a portion of the nitrogen enriched stream is used to produce power.
Davidian teaches that nitrogen rich gas produced by an air separation system (paragraph 13) can be used to dilute hydrogen gas sent to a gas turbine (paragraph 33).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have based on the teaching of Davidian to have taken a portion of the nitrogen generated in the air separation unit of Van der Walt as modified and used it to dilute the hydrogen sent to the gas turbine since it has been shown that combining prior art elements to yield predictable is obvious whereby diluting the hydrogen would provide the predictable result that would be common knowledge in the art of reducing the amount of nitrogen oxides produced.
Claim(s) 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Byfield and further in view of Turney.
With respect to claim 18, Van der Walt as modified does not teach (1) exporting at least a portion of the hydrogen containing stream produced in step (d) to a use that is external to the natural gas liquefaction system, the hydrogen production system, and the power generating system.
Turney teaches that a produced hydrogen sense (401) can be split for two uses (404/405) (paragraph 143), one of which is sent for ammonia synthesis (paragraph 147) or liquefaction (157).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have based on the teaching of Turney split the produced hydrogen stream of Van der Walt in two, one of which was used in the system for power production and other of which was used to produce a separate product stream either for liquefaction or ammonia synthesis since it has been shown that combining prior art elements to yield predictable results is obvious whereby providing the splitting of hydrogen stream would allow the predictable result for recovery as a useful product to be either used as ammonia synthesis or to be liquefied which would give it an additional use beyond power generation.
Claim(s) 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Byfield/Turner and further in view of Guillard et al. (US PG Pub 20180038638), hereinafter referred to as Guillard.
With respect to claim 20, Van der Walt does not teach rising: (m) cooling the hydrogen production system using refrigeration from the natural gas production system.
Guillard that the same stream heat exchanger (345) used to liquefy a natural gas stream (46) can be used to cool a first portion of a hydrogen stream (315) produced using a reformer in order to liquefy a first portion of the hydrogen (paragraphs 71-79).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have based on the teaching of Guillard to have taken a portion of the hydrogen stream in the hydrogen production system and have cooled it the natural gas refrigeration system (which would make that stream path part of the hydrogen production system) in Van der Walt since it has been shown that combining prior art elements to yield predictable results is obvious whereby providing cooling in this way would provide the predictable result of being able to utilize the natural gas liquefaction system to pre-cool a hydrogen stream which can then be liquefied to provide an additional product stream beyond just the LNG.
Claim(s) 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt and further in view of Minta and Teo (US PG Pub 20090255294), hereinafter referred to as Teo and Byfield.
While claims 24 refer to a “method of retrofitting”, this limitation is treated as a product by process limitation where if the combined system exists in the prior art it can be considered a method of retrofitting.
With respect to claim 24, Van der Walt (Figure 1) method of retrofitting a natural gas liquefaction system that at least partially liquefies natural gas feed stream at a feed temperature to form an LNG product at a product temperature comprising a heat exchanger and a compressor (natural gas from pipeline 102 is liquefied in 110 with a compressor, paragraph 104, which would be the existing natural gas liquefaction system), the method comprising:
(a) adding a hydrogen production system that reacts at least a portion of natural gas vapor stream produced by the natural gas liquefaction system to form a hydrogen-containing stream (a hydrogen production system is in the system alongside a LNG production system and thus the limitation is met, which hydrogen production uses boil-off gas paragraph 105);
(b) after performing step (a) at least partially liquefying the natural gas feed stream in the natural gas liquefaction system (102 is liquefied to form 110)
(c) generating power in a power generating system using the hydrogen containing stream and at least a portion of a first steam stream the hydrogen production steam (power is generated in the gas turbine 122 using the hydrogen and in a steam system, paragraph 114-115, and excess steam from the hydrogen production system is also used to drive compressors, paragraph 113 which would be generating power, and although they are separate components the gas turbine and the driver for the steam of the compressor together are an overall power generation system),
(d) providing power to a compressor with at least a portion of the power generated in step (b) (the compressor of the liquefaction unit receives power either mechanically or electrically from the gas turbine, paragraph 104).
Van Der Walt does not teach that the compressors of the liquefaction system include a first refrigeration compressor to compress refrigerant and provide compressed refrigerant, a second refrigeration compressor to further compress the compressed refrigerant and provide further compressed refrigerant and a third refrigeration compressor to compress propane to be used to cool the further compressed refrigerant and driving the second refrigeration compressor and the third refrigeration compressor by mechanically coupling a first gas turbine of the power generated in step (c) to the second refrigeration compressor and the third refrigeration compressor of the natural gas liquefaction system, and driving the first refrigeration compressor by mechanically coupling a second gas turbine to the first refrigeration compressor.
Byfield teaches (Figure 2) teaches a refrigeration compression arrangement of a natural gas liquefaction system (paragraph 21) where there are two gas turbines (1st driver 60 and 2nd driver 68, paragraphs, 41, 59-60) where the first driver is used for providing energy to a propane compressor (44, paragraph 57) and a compressor which compresses a different refrigerant which has already been compressed (MPMR and/or HPMR, paragraph 57) and a second driver is used to compressor a the refrigerant upstream of the MPMR and HPRM (low pressure first stage of compressor 12, paragraph 60). The turbines are connected to the compressors by shafts (58, 66, paragraphs 59-60).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have provided as the liquefaction system of Van Der Walt a configuration as in Byfield where there are at least three compressors, one which compresses the first refrigerant and is powered by a gas turbine via a shaft (second turbine and mechanical coupling) and a second compressor which further compresses the refrigerant as well as a propane compressor for compressing propane refrigerant which are together driven by another gas turbine via a shaft since it has been shown that combining prior art elements to yield predictable results is obvious whereby providing a natural gas liquefaction system with a propane pre-cooling system as well as a refrigerant compression system with multiple drivers would provide what would be common knowledge in the art of the ability to provide the necessary refrigeration for liquefying the natural gas while also providing the ability to drive the refrigerant cycles using suitable methods.
Van der Walt does not teach that the natural gas vapors produced by the natural gas liquefaction system are end flash.
Minta teaches that after liquefaction that the final LNG is flashed and separated into a flash vapor stream (16) which is used as fuel to power the compressor units of the refrigeration system and the LNG stream (15) (paragraph 24).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have prior to storage to have flashed the LNG stream of Van der Walt and used that stream for power generation as well (which in Van der Walt would mean using it as part of the hydrogen production, which is what Van der Walt does with all vapor natural gas containing streams) since it has been shown that combining prior art elements to yield predictable results is obvious whereby flashing the stream and separating the flash would increase the amount of fuel for use in energy generation while reducing the pressure and temperature of the LNG which would provide the predictable result of reducing boil off and flash in storage by bringing the pressure down prior to storage which would have the benefit that would be recognized in the art of providing further control to the power generation by producing controlling how much flash gas is sent for power generation.
Van der Walt does not teach in step b the LNG product has a second product temperature.
Teo teaches (Paragraphs 103-104) that raising the temperature of the liquefied stream of the system by a few degrees results in an increase in the amount of end gaseous flash gas produces which allows for shifting of the power requirements of the drivers of the compressors as desired.
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have based on the teaching of Teo in the retrofit of Van der Walt as modified to have increased the temperature of the liquefied product (which would in turn decrease the temperature different between the feed temperature and the product temperature) since it has been shown that combining prior art elements to yield predictable results is obvious whereby one having ordinary skill in the art would recognize the predictable result of increasing the liquefied temperature would allow for a reduction in compressor power required for the refrigeration system in one part as it is predictable to shift the power requirements for the compressors as desired.
Claim(s) 27 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Teo/Byfield and further in view of Gieskes.
With respect to claim 27, Van der Walt as modified does not teach wherein prior to performing step (a) the power generating system was adapted to provide power to the natural gas liquefaction and comprise the first gas turbine and the second gas turbine, the method further comprising: (f) modifying at least one first and the second gas turbine in the power generating system to be fueled by the hydrogen containing stream.
Gieskes teaches that in a non-integrated natural gas system that fuel gas turbines are fed by part of the natural gas feed (Column 2, lines 65-67) but in the integrated process that additional components including tail gas (40) are also fed to the turbines either together with or separate from part of the natural gas (Column 5, lines 1-5).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have had Van Der Walt as modified originally include the turbines as they are needed
when retrofitting had the gas turbines of Van der Walt as modified be considered a retrofit by using hydrogen to power them as in a system based on the teaching of Gieskes which shows that when integrating an existing natural gas system with gas turbines that the gas turbines of the system are powered by the retrofitted configuration and therefore it would have been obvious that when achieving the system of Van der Walt (which is considered a natural gas system combined with a hydrogen production system as modified) for the gas turbines that would previously have been powered by natural gas to have been powered by hydrogen as in Van der Walt since it has been shown that combining prior art elements to yield predictable results is obvious whereby providing using existing turbines would allow for the systems to be better integrated by not having to change out any existing systems when retrofitting.
Claim(s) 32 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt/Minta/Teo and further in view of Gieskes and Hinders et al. (US PG Pub 20190264582), hereinafter referred to as Hinders.
With respect to claim 32, Van der Walt as modified teaches wherein, prior to performing step (a), the power generating system was adapted to provide power to the natural gas liquefaction system and comprised the first gas turbine and the second gas turbine.
Gieskes teaches that in a non-integrated natural gas system that fuel gas turbines are fed by part of the natural gas feed (Column 2, lines 65-67) but in the integrated process that additional components including tail gas (40) are also fed to the turbines either together with or separate from part of the natural gas (Column 5, lines 1-5).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have when retrofitting had the gas turbines of Van der Walt as modified be considered a retrofit by using hydrogen to power them as in a system based on the teaching of Gieskes which shows that when integrating an existing natural gas system with gas turbines that the gas turbines of the system are powered by the retrofitted configuration and therefore it would have been obvious that when achieving the system of Van der Walt (which is considered a natural gas system combined with a hydrogen production system as modified) for the gas turbines that would previously have been powered by natural gas to have been powered by hydrogen as in Van der Walt since it has been shown that combining prior art elements to yield predictable results is obvious whereby providing using existing turbines would allow for the systems to be better integrated by not having to change out any existing systems when retrofitting.
Van der Walt does not teach blending the hydrogen containing stream and at least a portion of a steam stream formed from the hydrogen production system to fuel the at least one gas turbine. Van der Walt does teach the use of excess steam from the hydrogen production system (paragraph 113) but not that it is blended with the hydrogen.
Hinders teaches that a steam stream can be mixed with a hydrogen stream being burned in a combustion chamber to add mass to keep the steam in said combustion chamber within the thermal limits of the materials used in the gas turbine (paragraph 121). The steam stream is produced within the system of Hinders (see Figure 3B, which teaches generating steam with the system, paragraph 95)
Therefore, it would have been obvious to a person having ordinary skill in the art to have combined the steam stream (or a portion of the steam stream) produced in Van der Walt) with the hydrogen stream in the first and second gas turbines based on the teaching of Hinders in order to maintain the combustion chamber of the gas turbines within the thermal limits. As that is the steam stream already present in Van der Walt it would have been obvious to have used that stream as the stream mixed with the hydrogen as in Hinders which teaches using an internal steam stream.
Claim(s) 33 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Walt and further in view of Minta, Byfield and Hinders.
With respect to claim 33, Van der Walt teaches a method (Figure 1) comprising:
(a) at least partially liquefying a natural gas feed stream in a natural gas liquefaction system to form an LNG stream (natural gas from pipeline 102 is liquefied in 110, paragraph 104), the natural gas liquefaction system including at least one compressor (there is a compressor in the liquefaction system, paragraph 104);
(b) proving power to a compressor at least one gas turbine (power plant facility provides power through a gas turbine that receives hydrogen and would thus produce power which can be used to provide power to a compressor of the liquefaction system, paragraph 104)
(c) separating the LNG stream into a vapor stream and an LNG product stream (boil off gas is produced and separate from the LNG stream, paragraph 105);
(d) passing at least a portion of the vapor stream to a hydrogen production system (boil-off gas can be sent to hydrogen production, paragraph 105)
(e) reacting at least a portion of the vapor stream in the hydrogen production system to form a hydrogen containing stream and a first C02-enriched stream (in the hydrogen production, hydrogen and carbon dioxide are formed, paragraph 110, where hydrogen is passed to a gas turbine 122 and carbon dioxide is sent for capture 128, paragraph 111, 117), and a steam stream (combusted gas from the turbine can be used to generate waste heat which heats up steam which is then used to generate energy, paragraph 114-115).
Van Der Walt does not teach that the compressors of the liquefaction system include a first refrigeration compressor to compress refrigerant and provide compressed refrigerant, a second refrigeration compressor to further compress the compressed refrigerant and provide further compressed refrigerant and a third refrigeration compressor to compress propane to be used to cool the further compressed refrigerant and driving the second refrigeration compressor and the third refrigeration compressor by mechanically coupling a first gas turbine of the power generated in step (c) to the second refrigeration compressor and the third refrigeration compressor of the natural gas liquefaction system, and driving the first refrigeration compressor by mechanically coupling a second gas turbine to the first refrigeration compressor.
Byfield teaches (Figure 2) teaches a refrigeration compression arrangement of a natural gas liquefaction system (paragraph 21) where there are two gas turbines (1st driver 60 and 2nd driver 68, paragraphs, 41, 59-60) where the first driver is used for providing energy to a propane compressor (44, paragraph 57) and a compressor which compresses a different refrigerant which has already been compressed (MPMR and/or HPMR, paragraph 57) and a second driver is used to compressor a the refrigerant upstream of the MPMR and HPRM (low pressure first stage of compressor 12, paragraph 60). The turbines are connected to the compressors by shafts (58, 66, paragraphs 59-60).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have provided as the liquefaction system of Van Der Walt a configuration as in Byfield where there are at least three compressors, one which compresses the first refrigerant and is powered by a gas turbine via a shaft (second turbine and mechanical coupling) and a second compressor which further compresses the refrigerant as well as a propane compressor for compressing propane refrigerant which are together driven by another gas turbine via a shaft since it has been shown that combining prior art elements to yield predictable results is obvious whereby providing a natural gas liquefaction system with a propane pre-cooling system as well as a refrigerant compression system with multiple drivers would provide what would be common knowledge in the art of the ability to provide the necessary refrigeration for liquefying the natural gas while also providing the ability to drive the refrigerant cycles using suitable methods.
Van der Walt does not teach that the separating the LNG stream produces a flash vapor stream such that that is the stream passed to and reacting in the hydrogen production system.
Minta teaches that after liquefaction that the final LNG is flashed and separated into a flash vapor stream (16) which is used as fuel to power the compressor units of the refrigeration system and the LNG stream (15) (paragraph 24).
Therefore it would have been obvious to a person having ordinary skill in the art at the time the invention was filed to have prior to storage to have flashed the LNG stream of Van der Walt and used that stream for power generation as well (which in Van der Walt would mean using it as part of the hydrogen production, which is what Van der Walt does with all vapor natural gas containing streams) since it has been shown that combining prior art elements to yield predictable results is obvious whereby flashing the stream and separating the flash would increase the amount of fuel for use in energy generation while reducing the pressure and temperature of the LNG which would provide the predictable result of reducing boil off and flash in storage by bringing the pressure down prior to storage which would have the benefit that would be recognized in the art of providing further control to the power generation by producing controlling how much flash gas is sent for power generation.
Van der Walt does not teach blending the hydrogen containing stream and at least a portion of a steam stream formed from the hydrogen production system to fuel the first gas turbine and the second gas turbine. Van der Walt does teach the use of excess steam from the hydrogen production system (paragraph 113) but not that it is blended with the hydrogen.
Hinders teaches that a steam stream can be mixed with a hydrogen stream being burned in a combustion chamber to add mass to keep the steam in said combustion chamber within the thermal limits of the materials used in the gas turbine (paragraph 121). The steam stream is produced within the system of Hinders (see Figure 3B, which teaches generating steam with the system, paragraph 95)
Therefore, it would have been obvious to a person having ordinary skill in the art to have combined the steam stream (or a portion of the steam stream) produced in Van der Walt) with the hydrogen stream in the first and second gas turbines based on the teaching of Hinders in order to maintain the combustion chamber of the gas turbine within the thermal limits. As that is the steam stream already present in Van der Walt it would have been obvious to have used that stream as the stream mixed with the hydrogen as in Hinders which teaches using an internal steam stream.
Response to Arguments
Applicant’s arguments, see pages 10-14, filed 11/3/2025, with respect to the rejection(s) of claim(s) 1-10, 12-24, 27, 32-37 under 35 USC 103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Byfield (Figure 6). Although Byfield was used in the previous rejection, Byfield was not utilized in the rejection of the independent claim and further the rejections made with Byfield were made with Figure 6 which is the figure addressed in the arguments, not Figure 2 which is used in the present rejection.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BRIAN M KING whose telephone number is (571)272-2816. The examiner can normally be reached Monday - Friday, 0800-1700.
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, Frantz Jules can be reached at 5712726681. 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.
/BRIAN M KING/Primary Examiner, Art Unit 3763
Prosecution Insights