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 .
Election/Restrictions
Applicant’s election of Group I (claims 21-38), species 1 (Fig. 1), subspecies A in the reply filed on 6/5/2026 without traverse is acknowledged. Claims 19, 20, 32-34 and additionally claims 30, 38 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention or species, there being no allowable generic or linking claim. It is noted that claim 30 is not drawn to the elected species because the elected species does not have separate and additional compression in addition to the compression of the second combined stream to the recycle pressure already recited in claim 1. Also, claim 38 is not drawn to the elected species because the elected species does not compress the tertiary refrigeration return gas stream (35) in a separate low-pressure compressor, but is compressed in the recited first compressor (see 700).
Examiner Request
The applicant is requested to provide line numbers to each claim in all future claim submissions to aide in examination and communication with the applicant about claim recitations. The applicant is thanked for aiding examination.
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(s) 21-29, 31, 35-37 is/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 pre-AIA the applicant regards as the invention.
In regard to claim 21, the recitation, “by passing it” is indefinite for being unclear what is being referenced.
The recitation, “recycling the one or more refrigeration streams through the system until a desired cryogenic liquid storage temperature is reached.” is indefinite since “the system” lacks proper antecedent basis and since there is no way to determine what temperature is and is not cold enough to qualify. Further the recitation is indefinite since it is unclear if the recitation requires the refrigerant circulation to end when the desired temperature is reached or not.
In regard to claim 22, the recitation, “the clean gas stream is free of or reduced in impurities that tend to freeze at cryogenic temperatures.” is indefinite since the disclosure states that clean gas is defined as “substantially free of H2O, CO2, heavy hydrocarbons, BTEX, Mercaptans, H2S, and Hg.” (spec. para. 40, 38) therefore the present recitation is not consistent with the specification definition and the scope of what makes a gas stream “clean” is unclear. Further, there is no way to determine what the clean gas must be “reduced” relative to. Lastly, there is no way to determine what is and is not considered cryogenic temperatures as the term is broadly used to reference a whole range of inconsistent temperature ranges.
In regard to claim 23, the recitation, “to a cryogenic temperature” is indefinite since there is no way to discern what is sufficiently cold to qualify.
In regard to claim 24, the recitation, “the compressor steps” is unclear which compressor steps are included by the recitation.
In regard to claim 26, the recitation, “the monitoring” lacks proper antecedent basis.
In regard to claim 27, the recitation, “one or more stream” is indefinite as to what streams are being referenced and included and which are not included.
In regard to claim 28, the recitation, “a storage container” is indefinite and inconsistent with the recitations of claim 21, since claim 21 already recites and requires a liquid natural gas storage.
Further the recitation is unclear as it is not clear if the delivering recitation prevents delivery of fluid to the liquid natural gas storage until the recited temperature is reached or not.
Further claim 28 should depend from claim 21 not claim 1.
In regard to claim 29, the recitation, “one or more compressor are part” is indefinite for being inconsistent with the recitations of claim 21 and it is not clear if this refers to the one or more additional compressors already claimed in claim 21 and not clear why the recitation is not --the one or more compressors are part--.
In regard to claim 35, the recitation, “or expander;” is indefinite since claim 21 already recites a turbo-expander and there is no other expander as recited.
The recitation, “an expander, such as a turb-expander” is indefinite since claim 21 already requires and recites “a turbo-expander” and therefore the recitation is indefinite for improperly reintroducing the already presented turbo-expander.
The recitation, “with a compressor or expander” is repeated twice in claim 35 and is indefinite for not being consistent with the recitations of claim 21 that already requires and recites a “turbo-expander” and therefore the recitation is unclear for introducing another expander which is inconsistent with the disclosure.
The recitation, “with an expander” is indefinite since claim 21 already requires and recites “a turbo-expander” and the disclosure does not have another expander as recited and therefore the recitation is indefinite for improperly reintroducing the already presented turbo-expander.
In regard to claim 37, the recitation, “at expander” is indefinite since claim 21 already requires and recites “a turbo-expander” and the disclosure does not have another expander as recited and therefore the recitation is indefinite for failing to properly reference the turbo-expander.
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.
All of the claims have been evaluated under the three-prong test set forth in MPEP § 2181, subsection I, and it is considered that none of the claim recitations should be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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) 21-28, 35-37 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vemulapalli (US 2022/0252340) in view of Vemulapalli (US 2023/0366619) hereafter Vemu (619). See the indefiniteness rejections and note that the prior art teaches the claimed features as far as can be interpreted. Further note the interpretation of the claim language as outlined in the rejection below.
In regard to claim 21, Vemulapalli teaches a method for natural gas liquefaction (see whole disclosure, including fig. 1), comprising:
providing a clean gas stream (128, para. 30, 82, 83) and a recirculation gas stream (187) at a first pressure (thereof);
mixing the clean gas stream (128) and the recirculation gas stream (187) to form a mixed gas stream (to 139);
splitting the mixed gas stream (to 139) into at least a first stream (185) and a second stream (191);
passing the first stream (185) through a heat exchanger (130);
wherein the heat exchanger (130) cools the first stream (185) to form a first liquefied stream (toward 193) by cross exchanging with one or more refrigeration streams (142, 144, 146), wherein the one or more refrigeration streams (142, 144, 146) comprise:
an expander refrigeration stream (142);
a secondary refrigeration stream (144); and
a tertiary refrigeration stream (146); and
cooling the second stream (191) by passing the second stream (191) through the heat exchanger (130) to form a cooled gas stream (toward 150);
passing the cooled gas stream (toward 150) through a turbo-expander (turboexpander part of 150) to form the expander refrigeration stream (142);
passing the expander refrigeration stream (142) through the heat exchanger (130) to form a first refrigeration return gas stream (to 197);
generating a first slipstream (from 193 to 144) from the first liquefied stream (toward 193) and reducing pressure (see expansion valve) of the first slipstream (from 193 to 144) to form secondary refrigeration stream (144);
passing the secondary refrigeration stream (144) through the heat exchanger (130) to form a second refrigeration return gas stream (189);
combining the first refrigeration return gas stream (to 197) and the second return gas stream (189) to form a first combined stream (see streams are combined);
generating a second slipstream (from 193 to 146) from the first liquefied stream (toward 193) and reducing pressure (see expansion valve) of the second slipstream (from 193 to 146) to form reduced-pressure slip stream (from 193 to 146 after expansion valve);
combining the reduced-pressure slipstream (from 193 to 146 after expansion valve) with a boil off gas stream (from 170 at least, para. 85) from liquid natural gas storage (170) to form the tertiary refrigeration stream (146);
passing the tertiary refrigeration stream (146) through the heat exchanger (130) to form a tertiary refrigeration return gas stream (183); compressing the tertiary refrigeration return gas stream (183) using a first compressor (112a) to form a compressed tertiary refrigeration return gas stream (after 112a);
combining the compressed tertiary refrigeration return gas stream (after 112a) with the first combined stream (189, 197) to form a second combined stream (to 112C);
compressing the second combined stream (to 112C) using one or more additional compressor(s) (112C) to form the recirculation gas stream at pressure Precycle (para. 62);
reducing pressure of the first liquefied stream (via at least 199) to form a two-phase product stream (195; para. 86); and recycling the one or more refrigeration streams (142, 144, 146) to reach a desired cryogenic liquid storage temperature (para. 86).
Vemulapalli does not explicitly teach aftercooling the second combined stream. However, it is routine to perform aftercooling after compression for rejecting heat from refrigeration streams as taught explicitly by Vemu (619) (see at least 1400, para. 55). Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify Vemulapalli with aftercooling after the compressor (112C) for the purpose of improving the cooling capacity and heat rejection of the method.
In regard to claim 22, Vemulapalli teaches that the clean gas stream (128) has had impurities (para. 30, 81) removed.
In regard to claim 23, Vemulapalli teaches that the first stream (185) is cooled by the heat exchanger (130) to a cryogenic temperature (para. 85).
In regard to claim 24, Vemulapalli teaches that one or more of the compressing steps (at least the turbocompressor) is performed using at least part of work extracted at the turbo-expander (of 150).
In regard to claim 25, Vemulapalli teaches monitoring one or more of flow rate, flow volume, gas temperature, gas composition, or gas pressure (para. 4, 79, 80).
In regard to claim 26, Vemulapalli teaches adjusting one or more of
flow rate, flow volume, and/or flow ratio of one or more of the clean gas stream, the first stream, the second stream, the expander refrigeration stream, the secondary refrigeration stream, and/or the tertiary refrigeration stream based on monitoring (para. 4, 73, 80).
In regard to claim 27, Vemulapalli teaches expanding and cooling the first slip stream (from 193 to 144) by way of one or more pressure-reducing valves (see valves, para. 85).
In regard to claim 28, Vemulapalli teaches delivering the two-phase product stream (195) to the liquefied natural gas storage (170).
In regard to claim 35, Vemulapalli teaches that the compressing of the second combined stream (to 112C) is performed using a multi-stage compressor system (110) with: i) at least three compression stages (112ABC). In regard to claim 36, Vemulapalli teaches that a single motor (115) provides all external power required to perform the method (see no other external power for 150 or 112).
In regard to claim 37, Vemulapalli teaches that part of work extracted at the turbo-expander (of 150) is used in compressing the second combined stream (to 112C, aides in getting to the pressure thereof).
In regard to claim 29, Vemulapalli does not explicitly teach combining the turbo-expander and a compressor in a system coupled via a bull gear and pinions. However, combining turbo-expanders and compressors with pinions and a bull gear is well known as taught by Vemu (619). Vemu (619) teaches a turbo-expander (500) and compressor (1300) are part of a single system (compander package, Fig. 1) coupled via a bull gear and pinions (para. 28). Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify the turboexpander and compressors (110) of Vemulapalli to be driven together with other compressors via a bull gear and pinions as taught by Vemu for the purpose of efficiently providing power to a plurality of compressors using a single external driver and providing different speeds for the plurality of compressors so as to achieve a maximum efficiency while requiring fewer external drivers and for the purpose of reducing the footprint of the compression package.
In regard to claim 31, Vemulapalli, as modified above relative to claim 29, teaches that the compressing of the second combined stream (to 112C) is performed using a compander (compander modification from Vemu (619)).
In additional regard to claim 24, Vemulapalli, as modified above relative to claim 29, teaches that one or more of the compressing steps (see compressors combined in compander package) is performed using at least part of work extracted at the turbo-expander (from turbo-expander 150, per modification by Vemu (619)).
Conclusion
The prior art made of record on the 892 form and not relied upon is considered pertinent to applicant's disclosure. Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOHN F PETTITT whose telephone number is (571)272-0771. The examiner can normally be reached on M-F, 9-5p. 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): http://www.uspto.gov/interviewpractice. The examiner’s supervisor, Frantz Jules can be reached on 571-272-6681. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/JOHN F PETTITT, III/Primary Examiner, Art Unit 3763
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