DETAILED ACTION
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 .
Election/Restrictions
Applicant’s election with traverse of invention II (encompassing claims 11-15) in the reply filed on 05/18/2026 is acknowledged. Claims 1-10 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 05/18/2026. The traversal is on the ground(s) that (1) claim 11 constitutes a linking claim under MPEP § 803.02 and (2) both Groups involve co-extensive search. These arguments are unpersuasive. Under MPEP § 809.03, rejoinder based on an allowable linking claim is appropriate only when the linking claim is found allowable. Claim 11 is currently rejected under 35 U.S.C. § 103 as set forth above. Until claim 11 is allowed, the restriction requirement remains proper. Should claim 11 ultimately be found allowable, the Examiner will consider rejoinder of Group I claims under MPEP § 821.04.
The Examiner further notes that, under PCT Rule 13.2, the groups lack the same or corresponding special technical features because the common features (chamber S004 and associated elements) were found to lack novelty over the prior art (Enis, Fig. 4), as reflected in the restriction requirement. Therefore, the PCT unity-of-invention standard is not met, and restriction is proper under 35 U.S.C. § 372. The requirement is still deemed proper and is therefore made FINAL.
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.
Claims 11-15 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 11 recites the limitation "the group" in line 4 lacks proper antecedent basis. Examiner read the limitation as –a group--.
Claim 11 recites the limitation "the solidification of the carbon dioxide” in line 9 lacks proper antecedent basis. Examiner read the limitation as –a solidification of the carbon dioxide--.
Claim 11 recites the limitation "the pressure of said cooling fluid” in line 11 lacks proper antecedent basis. Examiner read the limitation as –a pressure of said cooling fluid--.
Claim 11 assigns reference numeral (20) to the first pipe (cooling fluid) and numeral (10) to the second pipe (gas to be treated) in the preamble, but concludes with "said first pipe (10) and said second pipe (20) being connected to said chamber (S004)," reversing those numerals. A person of ordinary skill in the art would not know with reasonable certainty whether "first pipe" carries cooling fluid or CO2-bearing gas, rendering claim 11 indefinite.
Claims 13 and 14 recites dependence from "claim 10," renders the claim indefinite because claim 10 is a withdrawn method claim. Applicant is requested to correct the dependency of claim 13 and 14 to claim 11 or another pending system claim. For examination purpose, examiner assumed claim 13 to be dependent upon claim 11 and claim 14 to be dependent upon claim 13.
Claim 12 is also rejected under 35 U.S.C. 112(b) for being dependent upon a rejected claim.
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) 11 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Enis et al. (US 2015/0260022 A1) in view of Baxter et al. (US 2018/0236397 A1).
In regard to claim 11, Enis teaches a system for capturing carbon dioxide comprising:
at least a first pipe (inlet pipe 45) in which at least one flow of fluid, referred to as cooling fluid, circulates, said cooling fluid having a temperature of less than or equal to -78.5°C, said cooling fluid being selected from the group made up of nitrogen, oxygen, air and mixtures thereof (¶ 0107, 0115, 0133, Figs. 4, 7: Enis discloses air is chilled to temperatures between −150°F and −180°F (approximately −101°C to −118°C), which is below −78.5°C, and delivered to a mixing chamber through multiple inlets. The cooling fluid is air, which is a mixture of nitrogen and oxygen, as expressly recited in claim 11),
at least a second pipe (47) in which at least one flow of gas, referred to as gas to be treated and containing at least in part carbon dioxide, circulates (¶ 0027–0028, 0103, 0133, Fig. 4, element 47: Enis discloses a CO2 gas supply that introduces the CO2 gas derived from an IGCC or power plant into the mixing chamber (43/123/201) through dedicated inlets),
at least one nozzle (100) adapted to be able to form at least one jet of said cooling fluid (air) and at least one jet of said gas to be treated (¶ 0106–0107, 0133, Fig. 4: Enis discloses multiple inlets 45 (for chilled air) and inlets 47 (for CO2 gas) through which the respective streams are injected as jets into mixing chamber 43. Each inlet acts to form a jet of the respective fluid),
a chamber (43/201) adapted to allow the solidification of the carbon dioxide by spraying said jet of cooling fluid and said jet of gas to be treated in contact with one another, said first pipe (45) and said second pipe (47) being connected to said chamber (43/201) (¶ 0106, 0110, 0115, 0133–0135, Figs. 4, 16: Enis discloses mixing chamber 43/201 as a chamber into which super-chilled air and CO2 gas are injected and mixed, causing the CO2 gas to freeze and form solid CO2 crystals. Both the chilled air supply inlets (45) and the CO2 gas supply inlets (47) are connected to chamber 43),
device (a screw device (55) or gravity-based portal (59)) for recovering carbon dioxide in the solid state (¶ 0029, 0111, 0140–0143, Fig. 4, elements 55, 59, 65: Enis discloses that frozen CO2 crystals are collected at the bottom of the mixing chamber, and a screw device (55) or gravity-based portal (59) collects and removes the agglomerated solid CO2).
Enis does not disclose a single combined nozzle simultaneously forming both jets.
Baxter discloses wall nozzles 112 through which carrier gas 118 containing a vapor such as carbon dioxide is injected directly into cryogenic liquid 116 within vessel 102, with injection points 508 flush with the inner vessel surface 510 (see Baxter, paragraphs 0009, 0012, 0021, 0025; Figures 1, 5, 6; elements 112, 118, 502, 508, 510). Baxter thus teaches a nozzle through which the CO2-bearing gas stream is actively injected into contact with a cryogenic fluid, performing the functional role of forming a jet of gas to be treated in contact with the cryogenic fluid.
It would have been obvious to one of ordinary skill in the art at the time of the invention to modify the system of Enis to incorporate the nozzle injection arrangement, as taught by Baxter to achieve more controlled and intimate contact between the cryogenic cooling fluid and the CO2-bearing gas at the injection point, with a reasonable expectation of improved CO2 solidification efficiency.
Enis does not explicitly disclose that the gas to be treated is at a pressure greater than the pressure of the cooling fluid.
Baxter discloses that carrier gas 118 (CO2-bearing flue gas or syngas) is injected through wall nozzles 112 into cryogenic liquid 116 flowing under tangential velocity within vessel 102 (see Baxter, paragraphs 0002, 0009, 0010, 0021; Figures 1-4; elements 102, 112, 114, 116, 118). Baxter further discloses that the nozzle injection points 508 are flush with the inner vessel wall (paragraph 0025; Figure 5; elements 502, 508, 510), establishing that the carrier gas must be supplied at a pressure sufficient to penetrate the flowing cryogenic liquid at those injection points and form discrete gas streams therein. Baxter expressly discloses that the carrier gas is "injected into" the cryogenic liquid (paragraph 0009), which requires that the carrier gas pressure exceeds the local cryogenic liquid pressure at the injection point. Furthermore, Baxter discloses that the vapor from the carrier gas dissolves, condenses, or desublimates into the cryogenic liquid, forming a vapor-enriched cryogenic liquid recovered through apex nozzle outlet 110 (see Baxter, paragraphs 0009, 0021; Figures 1-4; elements 106, 110, 120, 122), confirming that the carrier gas enters at the higher-pressure phase.
Therefore, It would have been obvious to one of ordinary skill in the art at the time of the invention, to modify the system of Enis by combining Enis's mixing chamber with the pressure-injection principle of Baxter, to arrive at the claimed configuration wherein the gas to be treated is at a pressure greater than the cooling fluid pressure, as this is a necessary physical condition in order for the CO2-bearing gas to form jets that penetrate and contact the cryogenic cooling fluid stream.
In regard to claim 12, Enis teaches the system as claimed in claim 11 (see the 112b above), wherein Enis discloses a gravity-and-screw solid recovery device (paragraphs 0140-0143, Figure 4, elements 55, 59, 65), but does not disclose a cyclone separator.
Baxter discloses a hydrocyclone vessel 102 comprising tangential feed inlet 104, vortex finder outlet 106 through which vapor-depleted carrier gas is drawn, and apex nozzle outlet 110 through which vapor-enriched cryogenic liquid 122 containing solidified CO2 is drawn, with the cyclone vortex causing gas/liquid separation (see Baxter, paragraphs 0009, 0021; Figures 1-5; elements 102, 104, 106, 108, 110, 120, 122). Baxter expressly identifies CO2 as the vapor of interest (paragraphs 0002, 0010, 0027; claim 2). Cyclone separators are a well-known class of separation equipment used to continuously separate solid particles or enriched liquid phases from a gas stream. Baxter demonstrates that a hydrocyclone is effective for separating CO2-enriched cryogenic liquid (containing solidified CO2) from a CO2-depleted carrier gas in a cryogenic CO2 capture application (paragraphs 0002-0004, 0009, 0021; Figures 1-5).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention, to replace the gravity/screw solid recovery device of Enis with the cyclone separator of Baxter, as taught by Baxter, in order to achieve continuous, steady-state separation of solid CO2 from the gas stream without reliance on batch screw operation, as the desirability of continuous over batch solid separation in industrial-scale CO2 capture was well known. This substitution represents the use of a known device (cyclone separator) in place of another device (gravity/screw separator) to perform the same function (recovering solid CO2), and one of ordinary skill in the art would have had a reasonable expectation of success in making this substitution.
Claim(s) 13 is rejected under 35 U.S.C. 103 as being unpatentable over Enis and Baxter as applied to claim 11 above, and further in view of Reddy et al. (US 9,339,752 B2).
In regard to claim 13, Enis teaches the system as claimed in claim 11, Enis does not disclose a condenser upstream of the solidification chamber using a recycled cooling flow from the chamber, and does not explicitly teach using cold effluent from the solidification chamber to pre-cool the incoming CO2-bearing feed gas.
However, using a heat exchanger upstream of a cryogenic separation vessel in which cold gas or liquid exiting the separation vessel is used to pre-cool and partially condense the incoming feed gas is a standard process design technique in cryogenic gas separation that was well known to those of ordinary skill in the art, as taught by Reddy, wherein Reddy teaches Reddy discloses a flue gas conditioning unit comprising heat exchanger E-101 that receives incoming flue gas (feed gas stream 101) and cool CO2-depleted flue gas (stream 109/110) exiting the desublimation unit, using the residual refrigeration content of stream 109/110 to pre-cool the incoming feed gas and produce precooled flue gas 106 (see Reddy, col. 2, lines 40-50; col. 4, lines 25-35; Figure 1A; elements E-101, streams 101, 106, 109, 110). Reddy further discloses that the flue gas conditioning unit includes a second heat exchanger that further cools the incoming flue gas using residual refrigeration content of the cool CO2-depleted flue gas leaving the first heat exchanger (see Reddy, col. 2, lines 52-57; Figure 1A). The cool CO2-depleted flue gas stream 109/110 exiting the desublimation unit constitutes a recycled cooling flow circulating from the separation chamber, and heat exchanger E-101 constitutes a condenser upstream of the solidification unit that uses that recycled flow to pre-cool and at least partially condense CO2 from the incoming gas to be treated. Reddy expressly discloses that partial condensation of CO2 occurs during this pre-cooling step, such that between 60% and 90% by volume of CO2 in the feed gas is recovered during the condensation step (see Reddy, col. 2, lines 40-50; Figure 1A).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to modify the modified Enis to add a pre-condensation heat exchanger upstream of the solidification chamber that uses cold gas or liquid exiting the chamber to partially condense CO2 from the incoming gas to be treated, as taught by Reddy, in order to reduces the refrigeration duty on the solidification chamber and improves overall energy efficiency.
The motivation to add a heat recovery step upstream of a cryogenic separation vessel arises from the fundamental and well-known engineering principle that cold process streams exiting a cryogenic unit have residual refrigeration value that can be recovered to reduce external refrigeration requirements. This represents the application of a known process design technique (feed pre-cooling by heat exchange with cold process effluent) to a known system (cryogenic CO2 solidification), and one of ordinary skill in the art would have had a reasonable expectation of success that such a heat exchanger would partially condense CO2 and reduce refrigeration load.
Claim(s) 14 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Enis and Baxter as applied to claim 13 above, and further in view of Zurecki et al. (US 2008/0048047 A1).
In regard to claim 14, Enis teaches the system as claimed in claim 11, wherein Enis discloses separate inlets (45 and 47) for the cooling fluid and CO2 gas respectively (paragraph 0133; Figure 4, elements 45, 47) but does not disclose a single coaxial nozzle producing a circular outer gas jet encircling a rectilinear inner cooling fluid jet. Baxter discloses wall nozzles 112 with injection points 508 flush with the vessel inner surface through which the CO2-bearing carrier gas is injected (paragraphs 0012, 0025; Figures 1, 5, 6; elements 112, 502, 508, 510) but does not disclose the specific coaxial circular-outer/rectilinear-inner jet geometry.
Zurecki discloses a cryogenic spray nozzle device comprising an outer conduit supplying gas and an inner conduit supplying cryogenic liquid, configured to form an outer annular circular gas jet surrounding an inner rectilinear cryogenic liquid jet exiting the nozzle in contact with one another (see Zurecki, paragraphs 0009-0018; Figures 1-5).
It would have been obvious to one of ordinary skill in the art at the time of the invention to implement the combined nozzle of the Enis-Baxter system using the coaxial nozzle configuration of Zurecki. Coaxial nozzles in which an outer annular gas jet surrounds an inner cryogenic liquid jet are a well-known class of spray nozzle used in cryogenic and gas-liquid contact applications, as evidenced by Zurecki. One of ordinary skill in the art would have been motivated to adopt the coaxial nozzle design of Zurecki in the Enis-Baxter system because coaxial nozzles of this type produce intimate, radially uniform mixing of two fluid streams at the point of ejection, which is desirable in a CO2 solidification system where thorough contact between the cooling fluid and the CO2-bearing gas directly affects the completeness of CO2 nucleation.
In regard to claim 15, Enis teaches the system as claimed in claim 11, further requires a flange (120) for connection to nozzle (100), comprising two endpieces (122, 125) adapted to be connected to said first pipe and to said second pipe. Zurecki discloses a nozzle device with separate supply inlets for gas and cryogenic liquid independently connectable to respective supply lines (see Zurecki, paragraphs 0013-0018; Figures 2-5). A flanged two-port connection assembly for attaching a dual-inlet nozzle to two separate supply pipes is a standard mechanical coupling element that was well within the ordinary skill in the art. Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to implement the plumbing connection between the coaxial nozzle and the two supply pipes of the modified Enis system using a flanged two-endpiece assembly of the type recited in claim. Flanged pipe connections are a universal and routine choice for making fluid-tight connections between nozzle inlets and supply pipes in industrial process equipment. The selection of a flanged two-endpiece connection in place of any other standard pipe connection mechanism represents a matter of routine engineering judgment that involves no inventive step, and one of ordinary skill in the art would have had a reasonable expectation of success that such a connection would provide a secure, fluid-tight interface between the nozzle and the two supply pipes.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to WEBESHET MENGESHA whose telephone number is (571)270-1793. The examiner can normally be reached Mon-Thurs 7-4, alternate Fridays, EST. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Frantz Jules can be reached at 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 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.
/W.M/Examiner, Art Unit 3763
/FRANTZ F JULES/Supervisory Patent Examiner, Art Unit 3763
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