DETAILED ACTION
The present application is being examined under the pre-AIA first to invent provisions.
Election/Restrictions
Claims 34 and 35 are rejoined.
As provided in 37 CFR 1.475(a), a national stage application shall relate to one invention only or to a group of inventions so linked as to form a single general inventive concept (“requirement of unity of invention”). Where a group of inventions is claimed in a national stage application, the requirement of unity of invention shall be fulfilled only when there is a technical relationship among those inventions involving one or more of the same or corresponding special technical features. The expression “special technical features” shall mean those technical features that define a contribution which each of the claimed inventions, considered as a whole, makes over the prior art. Claims 29-32 remain withdrawn as not having unity as the common features between the claims lack a special technical feature as demonstrated below relative to claim 21.
Examiner Request
The applicant is requested to provide line numbers to the claims.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim(s) 39 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
In regard to claim 39, the recitation, “the expanding of step (viii) of claim 21 is performed using a turbine” is new matter since claim 21 already states that the expanding of the recited step is performed by “a first expander” and there is no support for a first expander and some other turbine as recited.
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) 39 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
In regard to claim 39, the recitation, “the expanding of step (viii) of claim 21 is performed using a turbine” is indefinite since claim 21 already states that the expanding of the recited step is performed by “a first expander” and it is entirely unclear why the first expander is being reintroduced with a different name.
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 pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived 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 pre-AIA 35 U.S.C. 103(a) 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, 25, 27, 34, 39 are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Abdelmalek (US 5321946) in view of Josephson (US 1659431), Abdelmalek (US 5133190), and Ochs (US 7007474).
In regard to claim 21, Abdelmalek teaches a method (see whole disclosure including Fig. 1 and 3) for separating carbon dioxide (carbon dioxide, column 3, line 30) from a flue gas (column 4, line 5 “flue gas”) of a hydrocarbon processing plant (1; column 6, line 11), comprising:
(i) removing moisture (column 6, line 40-45; fig. 1) from the flue gas (flue gas) of the hydrocarbon processing plant (1) to yield an at least partially dried flue gas (toward 6);
(ii) compressing (via 101a), in a first compressor (101a), the at least partially dried flue gas (toward 6) to yield a compressed-gas stream (after 101a) having a temperature T0 (temperature thereof), wherein the compressed-gas stream (after 101a) includes the carbon dioxide (column 7, line 10-20) and an acid component (column 7, line 10-20);
(iii) reducing the temperature T0 of the compressed-gas stream (after 101a) to a temperature T1 using a first heat exchanger (at least 105, 106) wherein the acid component is condensed (column 8, line 5-10) thereby yielding a condensed acid component (liquid SO2) and a purified compressed-gas stream (19);
(iv) separating the condensed acid component (18, liquid SO2) from the purified compressed-gas stream (19) by directing the condensed acid component (18) out of the first heat exchanger (105, 106) as a side flow (see side flow 18);
(vi) reducing a temperature T1A of a stream from the purified compressed-gas stream (19) to a second temperature T2 using a second heat exchanger (108, 109), wherein T2 <T1 (column 8, line 1-20) and wherein at least a portion of the carbon dioxide from the purified further compressed-gas stream (19) condenses (column 8, line 45-51), thereby yielding a condensed-phase carbon dioxide component (liquid carbon dioxide; column 8, line 45-51) and a light-gas component (nitrogen in remaining gas towards 26);
(vii) separating the condensed-phase carbon dioxide component (liquid carbon dioxide; column 8, line 45-51) from the light gas component (nitrogen gas) in the second heat exchanger (108, 109) by directing the condensed-phase carbon dioxide component (liquid carbon dioxide) out of the second heat exchanger (108, 109) as a side flow (see liquid CO2 side flow) to produce a first light-gas stream (26);
(viii) expanding (via 101b), in a first expander (101b), at least a portion of the first light-gas stream (26) to form a cooled first light gas stream (27);
(ix) directing the cooled first light gas stream (27) to the second heat exchanger (108, 109) to provide refrigeration within the second heat exchanger (108, 109) and so that a second light gas stream (24) exits the second heat exchanger (108, 109);
directing at least a portion of the second light gas stream (24) to the first heat exchanger (105, 106) to provide refrigeration within the first heat exchanger (105, 106).
Abdelmalek does not explicitly teach
(vi) yielding a solid carbon dioxide;
(v) compressing the purified compressed gas stream (19) in a second compressor to form a purified further compressed-gas stream;
(x) expanding, in a second expander, the second light gas stream (24) from the second heat exchanger (108, 109) to form a cooled second light gas stream; and
(xi) directing the cooled second light gas stream to the first heat exchanger (105, 106) to provide the refrigeration within the first heat exchanger (105, 106).
However, it is routine to condense carbon dioxide into a solid to provide solid CO2 products as taught by Josephson. Josephson teaches a method for separating carbon dioxide (carbon dioxide, page 1, line 85-90) from a flue gas (page 1, line 85 “flue gas”) of a hydrocarbon processing plant (coke furnace page 1, line 100-105), comprising the steps of:
(i) removing moisture (at least page 2, line 5) from the flue gas (flue gas) of the hydrocarbon processing plant (coke furnace) to yield an at least partially dried flue gas (11);
(ii) compressing (via 12, 15, 18) the at least partially dried flue gas (11) to yield a compressed-gas stream (to 19, 20) having a temperature (thereof), wherein the compressed-gas stream includes the carbon dioxide (page 1 “carbon dioxide”);
(iii) reducing the temperature of the compressed-gas stream to a temperature T1 using a first heat exchanger (at least 19, 20) thereby yielding a purified compressed-gas stream (from 19, 20 to 21);
(vi) reducing a temperature of the purified compressed-gas stream (from 19, 20 to 21) to a second temperature T2 using a second heat exchanger (see structure having at least 21, 22, 47, 41), wherein T2 <T1 and wherein at least a portion of the carbon dioxide from the purified compressed-gas stream (to 19, 20) condenses (page 2, line 62-75), thereby yielding a solid condensed-phase carbon dioxide component (carbon dioxide component in the frozen carbon dioxide blocks, page 2, line 65-70, page 3, line 10-20) and a light-gas component (nitrogen component to 29 - page 2, line 45-56);
(vii) separating the solid condensed-phase carbon dioxide component (CO2 blocks) from the light gas component (nitrogen gas) in the second heat exchanger (at least 21, 22, 41, 47) by directing the solid condensed-phase carbon dioxide component (carbon dioxide) out of the second heat exchanger as a side flow (see CO2 blocks are removed from a side of the identified structure having at least 21, 22, 41, 47) to produce a first light-gas stream (nitrogen gas in 29); thereby Josephson clearly teaching the claimed yielding of a solid condensed-phase carbon dioxide to provide carbon dioxide solid product. Therefore it would have been obvious to those of ordinary skill in the art at the time of the invention to modify Abdelmalek with the forming or yielding of solid CO2 as taught Josephson for the purpose of providing solid carbon dioxide products to increase the utility of the method to be able to provide solid carbon dioxide to consumers.
In addition, providing several stages of compression and expansion is ordinary and routine and provides efficiency advantages.
Abdelmalek (190) teaches (i) removing moisture (column 8, line 15-20) from a flue gas (flue gas, column 2, line 45-51) to yield an at least partially dried flue gas (toward 41); (ii) compressing in a first compressor (41) the at least partially dried flue gas (toward 41) to yield a compressed-gas stream (after 41) having a temperature T0 (temperature thereof), wherein the compressed-gas stream (after 41) includes carbon dioxide and an acid component (column 2, line 50-55); (iii) reducing the temperature T0 of the compressed-gas stream to a temperature T1 using a first heat exchanger (42, 43) thereby yielding a condensed acid component (liquid SO2) and a purified compressed-gas stream (43B); (iv) separating the condensed acid component (43A, SO2) from the purified compressed-gas stream (43B) by directing the condensed acid component (43A) out of the first heat exchanger (42, 43); (v) compressing a purified compressed gas stream (43B) in a second compressor (51) to form a purified further compressed-gas stream (after 51). It is clearly seen that providing compression with a first and a second compressor improves an efficiency of compression by reducing an amount of fluid that is compressed to the higher compression ratio of the second compressor and thereby avoiding increasing the pressure of the acid component, while still maintaining the desired higher pressure ratio for the carbon dioxide condensation steps.
Further, Ochs teaches it is well known to provide staged expansion by expanding compressed flue gas (column 1, line 10-15). Ochs teaches (see whole disclosure, including at least fig. 2-4) that it is well known to remove water, SO2, and CO2 from flue gas (column 2, line 40-50) and then expand a remaining gas through a first expander (first expander; column 3, line 35-40, see expanders are turbines), provide heating to the expanded fluid (from the first expander) and then expand the fluid again with a second expander (second expander; column 3, line 35-40) to form a second expanded fluid and heat exchange the second expanded fluid for the purpose of recovering energy more effectively (column 1, line 30-34) and nets more energy than gained from “simply expanding all at once” (column 4, line 35-40) and provides higher power output (column 3, line 40-45) and provides practical and useful energy recovery from lower temperature energy sources (column 4, line 45-50).
Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify Abdelmalek with a second compressor as taught by Abdelmalek (190) for the purpose of improving the efficiency of compression by reducing the amount of fluid that is compressed to the higher compression ratio of the second compressor and thereby avoiding increasing the pressure of the acid component, while still maintaining the desired higher compression ratio for the carbon dioxide condensation steps; and further it would have been obvious to those of ordinary skill in the art at the time of the invention to modify Abdelmalek with a second expander to expand the second light gas stream (24) from the second heat exchanger (108, 109) of Abdelmalek for the purpose of providing additional power generation (column 3, line 40-45) and recovering energy more effectively (column 1, line 30-34) and netting more energy than gained from “simply expanding all at once” (column 4, line 35-40) and providing higher power output (column 3, line 40-45) and more practical and useful energy recovery from lower temperature energy sources (column 4, line 45-50); further such would increase the flexibility of operation and provide greater operational control of the refrigeration garnished from the expanders.
Note that the modification, as described, results in yielding a solid carbon dioxide; compressing the purified compressed gas stream (19) in a second compressor (from Abdelmalek (190)) to form a purified further compressed-gas stream; expanding, in a second expander (from Oochs), the second light gas stream (24) from the second heat exchanger (108, 109) to form a cooled second light gas stream; and directing the cooled second light gas stream (from the second expander of Oochs) to the first heat exchanger (105, 106) to provide the refrigeration within the first heat exchanger (105, 106).
In regard to claim 25, Abdelmalek teaches that the flue gas includes at least 10% carbon dioxide (column 7, line 10-15 - see 35-45% CO2) and at least 10% light gas (column 7, line 10-15 - see 50 % nitrogen).
In regard to claim 27, Abdelmalek teaches that the compressed gas stream (after 101a) is at a pressure of at least about 2 psi (column 7, line 50-55; column 8, line 50-55).
In regard to claim 34, Abdelmalek teaches that the acid component is SO2 (column 8, line 5-10).
In regard to claim 39, Abdelmalek teaches that the expansion of the step (viii) of claim 21 is performed using the first expander (101b), wherein the first expander (101b) provides power (se fig. 3) for driving the first compressor (101a) during the step (ii) of the claim 21.
Claim 35 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Abdelmalek (US 5321946) in view of Josephson (US 1659431), Abdelmalek (US 5133190), Ochs (US 7007474), Heichberger (US 4977745).
Abdelmalek does not explicitly state that a concentration of the acid component (SO2) in the purified compressed-gas stream (19) is less than 100 ppm. However, it is routine and ordinary to remove pollutants to a level below 100 ppm as taught by Heichberger. Heichberger teaches it is desired to remove an acid component (SO2, column 2, line 40-45) from a fluid gas. Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to operate Abdelmalek so that the method removes SO2 to a level below 100 ppm for the purpose of preventing such impurities in the CO2 product.
Claim(s) 21, 25, 27, 34, 39 are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Abdelmalek (US 5321946) in view of Josephson (US 1659431), Abdelmalek (US 5133190), Ochs (US 7007474), and Saysset (US 2008/0302133) and additionally, Claim 35 is/are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Abdelmalek (US 5321946) in view of Josephson (US 1659431), Abdelmalek (US 5133190), Ochs (US 7007474), Heichberger (US 4977745), and Saysset (US 2008/0302133).
See the rejections above and note that the prior art fully teaches the claimed features as outlined. In addition to this evidence, Saysset explicitly teaches that it is routine to separate condensed SO2 out of a heat exchanger as a side stream (see 155). Therefore it would have been obvious to those of ordinary skill in the art at the time the invention was made to modify the first heat exchanger (106, 108) of Abdelmalek to have the separating structure of Saysset for the purpose of providing a more compact separation structure.
Response to Arguments
Applicant's arguments filed 12/2/2025 have been fully considered but they are not persuasive in view of the new grounds of rejection.
Applicant's arguments (page 8) are an allegation that the prior art fails to teach the amended limitations. In response the applicant is directed to the detailed grounds of rejection above which show that the allegation is unpersuasive.
Applicant's arguments (page 8) are an allegation that “a person of ordinary skill in the art would not apply the 190’ patent to complete the process in the ‘946 Patent that requires fewer steps to achieve the same outcome”.
In response, the allegation is unpersuasive as the modification would not result in the same outcome but in an improved method and there is no support for the allegation.
Applicant's arguments (page 8) are an allegation that two compressors “would not be applied” to Abdelmalek because the compressors of the ‘190 patent are “not implemented in the same sequence as the compressor in the ‘946 Patent” relative to when acidic H2O is removed.
In response, the allegation is unpersuasive as there are no claim limitations excluding Abdelmalek from having a second compressor as described by the modification and no evidence against the use of staged compression as outlined. Further, there is no requirement in the law that a secondary reference used by a rejection must teach only the exact same features and have no differences with the primary reference and the allegation is unpersuasive. Further the benefits outlined by the rejection and provided by compressing in stages (using a second compressor) are not dependent on any of the identified differences.
Applicant's arguments (page 9) are an allegation that Abdelmalek only requires a single expander.
In response, the allegation is unpersuasive as the obviousness rejection is not that the method of Abdelmalek would fail to work without the modification but that the modification would be obvious for providing the identified benefits. Allegations that Abdelmalek operates fine without modification does nothing to the propriety of the rejection and fails entirely to respond to the position of the rejection that spells out in detail why one of ordinary skill in the art would make the modification.
Conclusion
The prior art made of record on the 892 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
January 9, 2026