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 .
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) 1-10 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 1, the recitation, “the outlet” is indefinite for lacking proper antecedent basis.
The recitation, “the liquefaction unit including a Stirling refrigeration cycle distinct from said precooling refrigeration cycle and implementing a first refrigerant, the Stirling refrigeration cycle comprising a precooling of the first refrigerant by heat exchange with a second refrigerant of a precooling refrigeration cycle distinct from a Stirling cycle,” is indefinite as it is not clear what “implementing a first refrigerant” encompasses and it is unclear if the first refrigerant is part of the Stirling refrigeration cycle or merely heat exchanged with the Stirling refrigeration cycle. Further the recitation is indefinite since the claim already introduced the precooling refrigeration cycle earlier in the claim and it is entirely improper to reintroduce the already described pre-cooling cycle. Further, it is unclear what would make the precooling refrigeration cycle distinct from “a Stirling cycle” since the disclosure is unclear. The applicant is applauded for providing definitions in the specification. The specification (pg. pub. para. 67) states that “a refrigeration cycle is “distinct from a Stirling cycle” if it is not implemented by a Stirling machine or does not possess one of the properties listed above.” While the first part of the definition is clear enough, unfortunately, it is not clear what properties the specification is referring to. The applicant is requested to confirm on the record what properties are being referenced by the disclosure in this citation. Further the recitation is indefinite since it is unclear what “precooling of the first refrigerant” includes and excludes since it is not clear how the cooling of the first refrigerant is “precooling” or what the cooling must be before or prior to in order to be considered “precooling”.
Note that the dependent claims listed in the rejection heading are also rejected at least for their dependency on indefinite claims.
In regard to claim 5, the recitation, “the temperature” is indefinite for lacking antecedent basis.
In regard to claim 10, the recitation, “a gas” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a purified gas” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a precooled gas” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a temperature” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “at least one precooling refrigeration” is indefinite for improperly reintroducing what was already previously recited in claim 1 and should be --the precooling refrigeration cycle--.
Further, the recitations obfuscate whether the precooling refrigeration cycle is part of the precooling unit or not.
The recitation, “a liquefaction unit” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a liquid stream” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a subcooling” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a Stirling refrigeration cycle” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a first refrigerant” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a precooling” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “at least one precooling refrigeration cycle distinct” is indefinite for improperly reintroducing what was already previously recited in claim 1 and claim 10.
The recitation, “a second refrigerant” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a heat exchange with the first refrigerant” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “to perform a precooling of the first refrigerant” is indefinite for improperly reintroducing what was already previously recited in claim 1. Further the recitation is indefinite since it is unclear what “precooling of the first refrigerant” includes and excludes since it is not clear how the cooling of the first refrigerant is “precooling” or what the cooling must be before or prior to in order to be considered “precooling”.
The recitation, “the precooling refrigeration cycle being distinct from a Stirling cycle” is indefinite since it is unclear what would make the precooling refrigeration cycle distinct from “a Stirling cycle” since the disclosure is unclear. The applicant is applauded for providing definitions in the specification. The specification (pg. pub. para. 67) states that “a refrigeration cycle is “distinct from a Stirling cycle” if it is not implemented by a Stirling machine or does not possess one of the properties listed above.” While the first part of the definition is clear enough, unfortunately, it is not clear what properties the specification is referring to. The applicant is requested to confirm on the record what properties are being referenced by the disclosure in this citation. Further, the recitation, “a Stirling cycle” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a subcooled liquid stream” is indefinite for improperly reintroducing what was already previously recited in claim 1.
The recitation, “a liquefied gas” is indefinite for improperly reintroducing what was already previously recited in claim 1.
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.
Claim limitation “expansion unit” invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph and is interpreted as a Joule-Thomson valve or a gas expansion turbine (see pg. pub. para. 59).
Claim limitation “purification unit” invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. However, the written description fails to disclose the corresponding structure, material, or acts for performing the entire claimed function and to clearly link the structure, material, or acts to the function. The disclosure describes some conventional structures in pg. pub. para. 57 but it is not clear if the purification unit comprises all of activated carbon, a condensation system, membrane system, molecular sieves or if the unit only comprises one of these or some other combination.
Therefore, the claim is indefinite and is rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. For present examination, the purification unit is interpreted as any one of the structures mentioned in para. 57 and this only requires either activated carbon, any system that removes water by cooling, any system that removes an impurity with a membrane of any kind, and any molecular sieve.
Claim limitation “precooling unit” invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. However, the written description fails to disclose the corresponding structure, material, or acts for performing the entire claimed function and to clearly link the structure, material, or acts to the function. The description uses the term but never defines what structure is necessary and sufficient. Therefore, the claim is indefinite and is rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. For present examination, the precooling unit is interpreted as a heat exchanger.
Claim limitation “subcooling unit” invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. However, the written description fails to disclose the corresponding structure, material, or acts for performing the entire claimed function and to clearly link the structure, material, or acts to the function. The disclosure uses the term but never defines what structure is necessary and sufficient. Therefore, the claim is indefinite and is rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. For present examination, the subcooling unit is interpreted as a heat exchanger.
Applicant may:
(a) Amend the claim so that the claim limitation will no longer be interpreted as a limitation under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph;
(b) Amend the written description of the specification such that it expressly recites what structure, material, or acts perform the entire claimed function, without introducing any new matter (35 U.S.C. 132(a)); or
(c) Amend the written description of the specification such that it clearly links the structure, material, or acts disclosed therein to the function recited in the claim, without introducing any new matter (35 U.S.C. 132(a)).
If applicant is of the opinion that the written description of the specification already implicitly or inherently discloses the corresponding structure, material, or acts and clearly links them to the function so that one of ordinary skill in the art would recognize what structure, material, or acts perform the claimed function, applicant should clarify the record by either:
(a) Amending the written description of the specification such that it expressly recites the corresponding structure, material, or acts for performing the claimed function and clearly links or associates the structure, material, or acts to the claimed function, without introducing any new matter (35 U.S.C. 132(a)); or
(b) Stating on the record what the corresponding structure, material, or acts, which are implicitly or inherently set forth in the written description of the specification, perform the claimed function. For more information, see 37 CFR 1.75(d) and MPEP §§ 608.01(o) and 2181.
Claim limitation “liquefaction unit” as recited in claim 1 has been evaluated under the three-prong test set forth in MPEP § 2181, subsection I, but the result is inconclusive. Thus, it is unclear whether this limitation should be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the disclosure never defines what structure the liquefaction unit must have but the claim does modify this language by stating that the liquefaction unit includes a Stirling refrigeration cycle which is considered clear structure sufficient to perform the function recited and therefore inasmuch as the recitation of the liquefication unit is interpreted to require some unknown additional structure other than the recited Stirling refrigeration cycle, then the recitation is considered indefinite since the boundaries of this claim limitation are ambiguous; therefore, the claim is indefinite and is rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. For present examination, the liquefaction unit is considered to merely require the Stirling refrigeration cycle.
In response to this rejection, applicant must clarify whether this limitation should be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. Mere assertion regarding applicant’s intent to invoke or not invoke 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph is insufficient. Applicant may:
(a) Amend the claim to clearly invoke 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, by reciting “means” or a generic placeholder for means, or by reciting “step.” The “means,” generic placeholder, or “step” must be modified by functional language, and must not be modified by sufficient structure, material, or acts for performing the claimed function;
(b) Present a sufficient showing that 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, should apply because the claim limitation recites a function to be performed and does not recite sufficient structure, material, or acts to perform that function;
(c) Amend the claim to clearly avoid invoking 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, by deleting the function or by reciting sufficient structure, material or acts to perform the recited function; or
(d) Present a sufficient showing that 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, does not apply because the limitation does not recite a function or does recite a function along with sufficient structure, material or acts to perform that function.
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) 1-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tung (US 2896414) in view of Zia (US 2015/0153100). 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 1, Tung teaches a method for liquefying a gas to be processed (column 1, line 16, natural gas) the method comprising:
purification (via 3) of the gas to be processed (natural gas) to obtain a purified gas (after 3),
precooling (via A, B) of the purified gas (after 3) to obtain a precooled gas (after B) having a temperature less than or equal to -15°C (see figure 1; ), the precooling being performed by heat exchange with a precooling refrigeration cycle (propane cycle)
liquefaction of the precooled gas (after B), in a liquefaction unit (C and Ethylene cycle), to obtain a liquid stream (after C; column 2, line 5-10), with a subcooling (via D) of the liquid stream (after C) of less than or equal to 5C at an outlet of the liquefaction unit (C; no subcooling is included herein), the liquefaction unit (C) distinct from said precooling refrigeration cycle (cycle with 10, 11) and implementing a first refrigerant (propane to B, A), the liquefaction cycle (ethylene cycle) comprising a precooling of the first refrigerant (propane) by heat exchange with a second refrigerant (propane in line to 17 from 16) of the precooling refrigeration cycle (propane cycle) distinct from the liquefaction cycle (C, ethylene cycle),
subcooling (via D; column 2, line 11) of the liquid stream (after C) to obtain a subcooled liquid stream (after D), and
expansion (via at least 4) of the subcooled liquid stream (after D) to obtain a liquefied gas (thereafter at least).
Tung does not appear to explicitly state that the gas to be processed comprises at least 50% methane. However, official notice is taken that natural gas routinely contains at least 50% methane. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to process a natural gas having at least 50% methane for the purpose of profiting from the most common form of natural gas and providing to market natural gas with more than 50% as demanded by the consumers of the market.
Tung does not teach that the liquefaction unit (C and ethylene cycle) includes a Stirling refrigeration cycle. However, it is well known to provide liquefaction with a Stirling refrigeration cycles as taught by Zia. Zia teaches a liquefaction unit (100; see whole disclosure including Fig. 3) providing liquefaction to natural gas (para. 20), the liquefaction unit (100) including a Stirling refrigeration cycle (para. 21-22, 78) able to provide easily controlled liquefaction temperatures in a small footprint and reduce the need for excess recirculation. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify the liquefaction unit (C and ethylene cycle) with a Stirling refrigeration cycle of Zia for the purpose of providing increased cooling capacity to increase liquefaction of natural gas with small refrigeration system size and provide a reduction in flash gas recirculation costs.
In regard to claim 2, Tung teaches that the precooling refrigeration cycle (propane cycle) forms a single precooling refrigeration cycle (propane cycle) and provides the precooling recited in claim 1.
In regard to claim 3, Tung teaches that the single precooling refrigeration cycle (propane cycle) is a propane cycle (column 1, line 72).
In regard to claim 4, Tung teaches that the single precooling refrigeration cycle (propane cycle) comprises: cooling the second refrigerant (propane is cooled by expansion; column 3, line 1-10) to produce a cooled second refrigerant stream (cooled propane after expansion), and dividing (after 16) the cooled second refrigerant stream (cooled propane after expansion) into at least two flows (to 17, to B) used respectively to perform the precooling of the first refrigerant (of ethylene in 17) and the precooling of the purified gas (in B).
In regard to claim 5, Tung teaches that the temperature of the precooled gas (after A, B) is higher than or equal to -50°C (see -50C is -58F and -30F taught by Tung is higher than -58F).
In regard to claim 6, Tung teaches that the subcooling (in D) comprises: a heat exchange with a vapor (sent to 10, 11) produced by the expansion of the subcooled liquefied gas stream (via at least 4).
In regard to claim 7, Tung teaches that the expansion of the subcooled liquid stream (via 4) produces a vapor (to 10, 11), the method further comprising mixing the gas to be processed (natural gas) with at least a portion of the vapor (sent to 10, 11) to obtain a mixture (see mixing in fig. 1).
In regard to claim 8, Tung, as modified, teaches most of the claim limitations but does not appear to explicitly teach expansion of the precooled gas (after A, B) prior to the liquefaction unit (C and ethylene cycle and Stirling cycle of Zia). However, Zia teaches explicitly that expanding a precooled natural gas (104) prior to the liquefaction unit (100) provides an increased efficiency in liquefaction (para. 49-50, 52). Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify Tung with an additional stage of expansion of the precooled gas (after A, B) as taught by Zia to improve the efficiency of liquefaction as taught by Zia.
In regard to claim 9, Tung teaches that said liquid stream (after C) obtained presents a temperature of between -115°C and -90°C (-140F is -95C) at the outlet of the liquefaction unit (C and ethylene cycle as modified above).
In regard to claim 10, Tung, as modified above, teaches the limitations of claim 10, including a facility adapted to implement the method according to claim 1 (see above), comprising: a purification unit (3) able to purify the gas to be processed (natural gas) comprising at least 50% by volume of methane (as most natural gases are as outlined above) and to obtain the purified gas (from 3), \a precooling unit (A, B, with propane cycle) able to precool the purified gas (from 3) with a precooling refrigeration cycle (propane cycle) and to obtain the precooled gas (after A, B) at the temperature less than or equal to -15C (see Fig. 1), a liquefaction unit (C, Ethylene cycle, and Stirling refrigeration cycle of Zia) able to liquefy the precooled gas (from A, B) and to obtain the liquid stream (after C), at the outlet of the liquefaction unit (C, Ethylene cycle, and Stirling refrigeration cycle of Zia) (see that the liquid has less than 5C of subcooling), the liquefaction unit (C, Ethylene cycle, and Stirling refrigeration cycle of Zia) including the Stirling refrigeration cycle (Zia 100) distinct from said precooling refrigeration cycle (propane cycle) and being able to implement the first refrigerant (ethylene refrigerant as ethylene cycle is part of liquefaction unit with the Stirling cycle of Zia), the Stirling refrigeration cycle (Zia 100) being able to perform the precooling of the first refrigerant (propane), the precooling refrigeration cycle (propane cycle) distinct from the Stirling refrigeration cycle (Zia 100) and able to implement the second refrigerant (propane to 17) and to perform the heat exchange with the first refrigerant (ethylene) in order to obtain said precooling of the first refrigerant (ethylene is precooled), the precooling refrigeration cycle (propane cycle) being distinct from the Stirling cycle (the refrigerants thereof do not mix), a subcooling unit (D) for subcooling the liquid stream (after C) to obtain the subcooled liquid stream (to 4), and an expansion unit (JT valve 4) for expanding the subcooled liquid stream (to 4) to obtain the liquefied gas (after 4).
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
JFPIII
February 5, 2026
/FRANTZ F JULES/Supervisory Patent Examiner, Art Unit 3763