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 .
Drawings
The drawings submitted on 6/11/2026 are accepted.
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) 2, 35-36 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 2, the recitation, “wherein the adjusting of the flow of the mixing stream to the fuel product stream of step (e)” is indefinite for improperly reintroducing “step (e)” and it is unclear why the recitation is not -- wherein the adjusting of the flow of the mixing stream of the step (e)--.
In regard to claim 35, the recitation, “wherein adjusting flow of the mixing stream” is indefinite for improperly reintroducing “adjusting” and “flow” anew without reference to the previously recited adjusting and flow.
Claim Interpretation
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) 1-3, 9, 12, 13, 16, 22, 24, 25, 27, 29-37 is/are rejected under 35 U.S.C. 103 as being unpatentable over Chen (US 2015/0308737) in view of Van Amelsvoort (EP 2796818) and Alexandra (BR 112012001046). See the 112 rejections and note that the claims are met by the prior art as far as can be interpreted.
In regard to claim(s) 1, 2, 24, 32, 37, Chen teaches a method (see whole disclosure, including Fig. 6) comprising:
(a) cooling and at least partially liquefying a natural gas feed stream (100) to form a cooled LNG stream (108) having a cooled LNG nitrogen concentration (nitrogen concentration thereof);
(b) performing a plurality of phase separations (see separations figure 6) in downstream fluid flow communication with the cooled LNG stream (108) to produce a nitrogen vapor stream (136) having a vapor stream nitrogen concentration (thereof), a fuel stream (liquid descending within 534) having a fuel stream nitrogen concentration (thereof), and an LNG product stream (132) having an LNG product stream nitrogen concentration (thereof), wherein the vapor stream nitrogen concentration (of 136) is greater than the cooled LNG nitrogen concentration (108), the fuel stream nitrogen concentration (nitrogen of liquid descending within 534) and the LNG product stream nitrogen concentration (nitrogen of 132) (due to nitrogen separation steps; para. 76),
(c) combining the fuel stream (liquid descending within 534) with a mixing stream (574) to create a fuel product stream (138) having a fuel product stream nitrogen concentration (thereof), the fuel product stream nitrogen concentration being greater than the fuel stream nitrogen concentration (of liquid descending within 534 due to fluid with unseparated nitrogen entering from 574), the mixing stream (574) being in downstream fluid flow communication with the cooled LNG stream (108); and
(d) recycling a recycle stream (572) comprising a portion of the nitrogen vapor stream (136) as reflux (sent to top of 534) for a rectification column (534);
wherein the natural gas feed stream (100) has a feed stream nitrogen concentration (thereof) and the feed stream nitrogen concentration is equal to the cooled LNG nitrogen concentration (see that the there is no removal of nitrogen from 100 to 108); further note that the mixing of Chen leaves the LNG product stream nitrogen concentration unchanged (see that the nitrogen concentration of 132 is not altered by the mixing of 574 with the liquid descending within 534).
Chen does not explicitly teach adjusting flow of the mixing stream (574) combined with the fuel stream (liquid descending within 534) to provide the fuel product stream nitrogen concentration (of 138) at or below a maximum fuel gas nitrogen, and does not teach that the adjusting comprises adjusting a valve; and does not explicitly teach that the maximum fuel gas nitrogen concentration of the fuel product stream (138) is 15 mole percent.
However, it is well known to provide adjustment of a mixing stream as taught by Van Amelsvoort. Van Amelsvoort teaches adjusting flow of a mixing stream (11) via adjusting a valve (15) to provide a fuel product stream nitrogen concentration (nitrogen concentration of fluid to gas turbine 320 from combination of 11 and 40) at or below a maximum fuel gas nitrogen concentration (para. 23 between 10% and 30%) so as to provide a fuel product stream (to gas turbine 320 from the combination of 11 and 40) to a gas turbine (gas turbine para. 23) so that the gas turbine does not receive too much nitrogen in its fuel.
In addition to the above evidence, Alexandra also explicitly teaches that it is routine and common for gas turbines to have a maximum nitrogen content of 15 mol% in their gas fuels (page 6, para. 8).
Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify Chen with a gas turbine fueled by the fuel product stream (138) for the purpose of providing power production from the natural gas on hand and reducing the need for external power generation and to modify Chen with the adjusting of the mixing stream as taught by Van Amelsvoort for the purpose of reducing the needed size for the nitrogen column (para. 23) and for the purpose of ensuring that the fuel product stream to the gas turbine does not contain too much nitrogen and ensure that the nitrogen concentration of the fuel product stream is below a maximum value (para. 23) for the purpose of ensuring proper operation of the gas turbine and to also employ a maximum value of 15% as suggested by Alexandra so as to accommodate common gas turbines.
In rehearsed regard to claim 2, Chen, as modified, teaches that the adjusting of the flow of the mixing stream (574) of the step (e) comprises adjusting a valve (see operation of valve 15 of Van Amelsvoort applied to Chen).
In regard to claim 3, Chen teaches that at least one of the plurality of phase separations of the step (b) is performed in the rectification column (534) and the fuel stream (descending liquid in 534) is withdrawn as a liquid (as part of the fuel product stream 138) from a bottom end (see bottom of 534) of the rectification column (534).
In regard to claim 9, Chen teaches that at least one of the plurality of phase separations further comprises phase separating (via 114) the cooled LNG stream (108) to produce a flash gas stream (116) and the LNG product stream (132).
In regard to claim 12, Chen teaches that the plurality of phase separations further comprises introducing at least a first portion (122) of the flash gas stream (116) into the rectification column (534) to produce the nitrogen vapor stream (136) and the fuel stream (liquid descending in 534).
In regard to claim 13, Chen teaches that the mixing stream (574) comprises a second portion (part of 116) of the flash gas stream (116).
In regard to claim 16, Chen teaches venting (interpreted as outputting for some other use or purpose; see 136 is output) the nitrogen vapor stream (136).
In regard to claim 22, Chen does not appear to teach pumping the LNG product stream (132) to an LNG storage tank. However, official notice is taken that it is routine and ordinary to pump LNG product from one storage to another for the purpose of moving liquid for transportation of the natural gas and as part of selling operations. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify the Chen by pumping the LNG product stream (132) to another LNG storage tank for the purpose of selling the liquid and transporting the natural gas to other users away from where the process of Chen is located.
In rehearsed regard to claim 24, Chen, as modified, teaches that the maximum fuel nitrogen concentration is 15 mole percent (see Alexandra).
In regard to claim(s) 25, 27, 29, Chen teaches a method (see whole disclosure, including Fig. 6) comprising:
(a) cooling and at least partially liquefying a natural gas feed stream (100) to form a cooled LNG stream (108) having a cooled LNG nitrogen concentration (nitrogen concentration thereof);
(b) performing a plurality of phase separations (see separations figure 6) in downstream fluid flow communication with the cooled LNG stream (108) to produce a nitrogen vapor stream (136) having a vapor stream nitrogen concentration (thereof), a fuel stream (liquid descending within 534) having a fuel stream nitrogen concentration (thereof), and an LNG product stream (132) having an LNG product stream nitrogen concentration (thereof), wherein the vapor stream nitrogen concentration (of 136) is greater than the cooled LNG nitrogen concentration (108), the fuel stream nitrogen concentration (nitrogen of liquid descending within 534) and the LNG product stream nitrogen concentration (nitrogen of 132) (due to nitrogen separation steps; para. 76),
(c) combining the fuel stream (liquid descending within 534) with a mixing stream (574) to create a fuel product stream (138) having a fuel product stream nitrogen concentration (thereof), the fuel product stream nitrogen concentration being greater than the fuel stream nitrogen concentration (of liquid descending within 534 due to fluid with unseparated nitrogen entering from 574), the mixing stream (574) being in downstream fluid flow communication with the cooled LNG stream (108); and
(d) recycling a recycle stream (572) comprising a portion of the nitrogen vapor stream (136) as reflux (sent to top of 534) for a rectification column (534);
whereby the step (c) comprises controlling the fuel product stream nitrogen concentration (nitrogen concentration of 138) independently of the LNG product stream nitrogen concentration (of 132)(per arrangement of the lines and separations).
Chen does not explicitly teach vaporizing the fuel product stream (138) comprising the fuel stream (liquid descending within 534) and the mixing stream (574) to produce a vaporized fuel stream; adjusting flow of the mixing stream (574) combined with the fuel stream (liquid descending within 534) to provide the fuel product stream nitrogen concentration (of 138) at or below a maximum fuel gas nitrogen concentration, and does not teach that the adjusting comprises adjusting a valve; and does not explicitly teach that the maximum fuel gas nitrogen concentration of the fuel product stream (138) is 15 mole percent.
However, it is well known to provide a vaporized fuel product stream and adjustment of a mixing stream as taught by Van Amelsvoort. Van Amelsvoort teaches vaporizing a fuel product stream (see combined stream of 11 and 40 have at least a portion that is vaporized and sent to line 230 and eventually to the gas turbine 320); adjusting flow of a mixing stream (11) via adjusting a valve (15) to provide a vaporized fuel product stream nitrogen concentration (nitrogen concentration of fluid to gas turbine 320 from combination of 11 and 40) at or below a maximum fuel gas nitrogen concentration (para. 23 between 10% and 30%) so as to provide a fuel product stream (to gas turbine 320 from the combination of 11 and 40) to a gas turbine (gas turbine para. 23) so that the gas turbine does not receive too much nitrogen in its fuel.
In addition to the above evidence, Alexandra also explicitly teaches that it is routine and common for gas turbines to have a maximum nitrogen content of 15 mol% in their gas fuels (page 6, para. 8).
Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify Chen with a gas turbine fueled by a vaporized fuel product stream (138) for the purpose of providing power production from the natural gas on hand and reducing the need for external power generation as taught by Van Amelsvoort and to modify Chen with the adjusting of the mixing stream as taught by Van Amelsvoort for the purpose of reducing the needed size for the nitrogen column (para. 23) and for the purpose of ensuring that the fuel product stream to the gas turbine does not contain too much nitrogen and ensure that the nitrogen concentration of the fuel product stream is below a maximum value (para. 23) for the purpose of ensuring proper operation of the gas turbine and to also employ a maximum value of 15% as suggested by Alexandra so as to accommodate common gas turbines.
In regard to claim(s) 30, 33, Chen, as modified, teaches using the vaporized fuel stream as fuel for at least one gas turbine (see 320 of Amelsvoort).
In regard to claim(s) 31, 34, Chen teaches driving at least one compressor adapted to compress a refrigerant used to perform the step (a) (para. 96 - see 652, 660), but not that the gas turbine drives these refrigerant compressors. However, Amelsvoort makes clear that driving refrigerant compressors with the gas turbine (320) using the vaporized fuel is routine and ordinary (para. 54, 96). Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to power the compressors of Chen with the gas turbine fueled by the vaporized fuel stream of Amelsvoort for the purpose of making immediate use of the power generated by the gas turbine and reducing the need for external power for the refrigerant compressors.
In regard to claim 35, Chen, as modified, teaches that the adjusting of the flow of the mixing stream (574) to the fuel product stream (138), via the valve as outlined by the combination of teachings as identified above, does not change the LNG product stream nitrogen concentration (nitrogen of 132, see that the nitrogen amount in line 132 is unchanged by the adjusting of a valve provided on line 574).
In rehearsed regard to claims 36, 37, Chen, as modified, teaches that the maximum fuel gas nitrogen concentration is of equipment (gas turbine 320 of Amelsvoort) being fueled by the fuel product stream (138 as outlined in the obviousness rejection of claims 1, 35 above).
Response to Arguments
Applicant’s arguments filed 6/11/2026 have been considered but are not persuasive.
Applicant's arguments (page 12-13) are an allegation that one of ordinary skill in the art would not have been motivated to make the combination of the rejection. In response, the allegation is unpersuasive as the rejection has clearly articulated the motivation for the combination.
Applicant's arguments (page 13) are an allegation that the rejection is based only on impermissible hindsight. In response, the allegation is unpersuasive since there is no basis of the rejection that relies upon the applicant’s disclosure or invention. The rejection is wholly founded on the teachings of the prior art.
Applicant's arguments (page 13) are an allegation that the prior art does not teach the amended features. In response, the allegation is unpersuasive and the applicant is directed to the detailed grounds of rejection above that demonstrates that all of the claimed features are met by the prior art.
Applicant's arguments (page 13-14) are an allegation that Van Amelsvoort does not disclose adjusting valve 15 adjusts the flow of the second feed line 11 to a stream to gas turbine 320. In response, the allegation is unpersuasive for ignoring that the combined fluid (thru 50, 64, 260, 70, 240, 360) is indeed fed to the gas turbine (320; para. 96) and therefore there is no basis for the allegation.
Conclusion
The prior art made of record on the 892 and not relied upon is considered pertinent to applicant's disclosure.
Applicant's amendment necessitated any of 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 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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