GENERAL ELECTRIC TECHNOLOGY GMBH

Patent Trials and Appeals BoardMay 17, 2021

2020003398 (P.T.A.B. May. 17, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 14/193,052 02/28/2014 Sandra GUIDOLIN GE 310310-8- US (1020-0109 1929 132545 7590 05/17/2021 GROGAN, TUCCILLO & VANDERLEEDEN, LLP 1350 Main Street, 5th Floor Springfield, MA 01103 EXAMINER NASSIRI MOTLAGH, ANITA ART UNIT PAPER NUMBER 1734 NOTIFICATION DATE DELIVERY MODE 05/17/2021 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): docket@gtv-ip.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte SANDRA GUIDOLIN, ULRICH KOSS, and PETER KNIESBURGES Appeal 2020-003398 Application 14/193,052 Technology Center 1700 Before JEFFREY T. SMITH, JULIA HEANEY, and SHELDON M. McGEE, Administrative Patent Judges. HEANEY, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the Examiner’s decision to reject claims 1–15. See Final Act. 1. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies the real party in interest as General Electric Technology GmbH. Appeal Br. 3. Appeal 2020-003398 Application 14/193,052 2 CLAIMED SUBJECT MATTER The claims are directed to an absorber for capturing CO2 in ammoniated solution. Claim 1, reproduced below, is illustrative of the claimed subject matter: 1 A method of capturing CO2 from a flue gas stream in a CO2 -absorber, the method comprising: - providing, between a first absorption stage and a second absorption stage of the CO2 - absorber, a CO2 -lean ammoniated solution, -contacting, in the first absorption stage of the CO2 -absorber, the flue gas stream with a mixture of the CO2-lean ammoniated solution, a first portion of a recirculated CO2- enriched ammoniated solution having passed through the second absorption stage, and a second portion of the recirculated CO2- enriched ammoniated solution having passed through a third absorption stage and the second absorption stage to form a partly cleaned flue gas stream, - providing, between the second absorption stage and the third absorption stage of the CO2 -absorber, the first portion of the recirculated CO2-enriched ammoniated solution, - contacting, in the second absorption stage of the CO2 - absorber, a partly cleaned flue gas stream with a mixture of the first portion of the recirculated CO2-enriched ammoniated solution and the second portion of the recirculated CO2-enriched ammoniated solution having passed through the third absorption stage to form a cleaned flue gas stream, -providing, above the third absorption stage of the CO2 -absorber, the second portion of the recirculated the CO2- enriched ammoniated solution, -contacting, in the third absorption stage of the CO2 -absorber, the cleaned flue gas stream with a third portion of the recirculated CO2-enriched ammoniated solution to form a further cleaned flue gas stream, - forming a collected CO2-enriched ammoniated solution by collecting the mixture of the CO2-lean ammoniated solution and the first and second portions of the recirculated CO2- Appeal 2020-003398 Application 14/193,052 3 enriched ammoniated solution after having passed through the first absorption stage, - passing a first portion of the collected CO2-enriched ammoniated solution for regeneration for removing CO2 from the first portion of the collected CO2-enriched ammoniated solution to form the CO2-lean ammoniated solution, - utilizing a second portion of the collected CO2-enriched ammoniated solution to form the first portion of the recirculated CO2-enriched ammoniated solution, and -utilizing a third portion of the collected CO2-enriched ammoniated solution to form the second portion of the recirculated CO2-enriched ammoniated solution. Appeal Br. 19–20 (italics indicating claim elements discussed below). REFERENCES The prior art relied upon by the Examiner is: Name Reference Date Gal US 2009/0101012 A1 Apr. 23, 2009 Dube US 2011/0120308 A1 May 26, 2011 Park Absorption Characteristic of Continuous CO2 Absorption Process, 49 Prepr. Pap. Am. Chem. Soc. Div. Fuel Chem., 249–250. 2004 REJECTIONS Claim(s) Rejected 35 U.S.C. § Reference(s)/Basis 1–3, 5–12, 14, 15 103 Gal 4 103 Gal, Dube 13 103 Gal, Park Appeal 2020-003398 Application 14/193,052 4 OPINION Obviousness of Claims 1–3, 5–12, 14, and 15 over Gal First absorption stage The Examiner finds that Gal teaches a method of capturing CO2 from a flue gas stream in a CO2 absorber. Final Act. 2 (citing Gal Abstr.). The Examiner acknowledges that Gal does not explicitly teach contacting in a first absorption stage the flue gas with a mixture of the CO2-lean ammoniated solution, a first portion of a recirculated CO2-enriched ammoniated solution having passed through the second absorption stage, and a second portion of the recirculated CO2-enriched ammoniated solution having passed through a third absorption stage and the second absorption stage to form a partly cleaned flue gas stream. Id. at 4. Appellant argues that Gal does not provide a CO2-lean ammoniated solution between a first absorption stage and a second absorption stage of the CO2 absorber. Appeal Br. 9. Appellant argues that Gal introduces a lean solution at the third stage of the absorber. Appeal Br. 9, 11 (citing Gal Fig. 2B). Appellant argues that moving the CO2-lean ammoniated incoming stream to another location would render Gal inoperable for its intended purpose. Appeal Br. 8. The Examiner finds that Gal introduces CO2-lean ammoniated solution at the top of the absorber at the third stage, but disagrees that “moving the CO2-lean solution incoming stream to another location in the absorber to achieve desired R value” would render Gal inoperable for its intended purpose. Ans. 4–5. We are not persuaded that providing a CO2-lean ammoniated solution between a first absorption stage and a second absorption stage of the CO2 absorber as claimed would necessitate any modification to Gal. Figures 2A Appeal 2020-003398 Application 14/193,052 5 and 2B in Gal depict introducing a CO2-rich ammoniated ionic solution collected from a third absorption stage (276), and introducing a regenerated lean ionic solution between a first absorption stage (272) and a second absorption stage (274), where the ionic solution is ammonia-based. Gal ¶¶ 33, 42, 47. Thus, Gal already provides a CO2-lean ammoniated solution between the first and second stages of its absorption system, and we disagree with Appellant that a person of ordinary skill in the art would have found it necessary to modify Gal by moving the CO2-lean solution stream. Id. Therefore, Appellant has not identified reversible error as to whether Gal provides a CO2-lean ammoniated solution between a first absorption stage and a second absorption stage of the CO2 absorber. Second absorption stage The Examiner finds that in the second absorption stage of Gal’s CO2- absorber, Gal does not explicitly teach a mixture of CO2-lean ammoniated solution and a first and second portion of the recirculated CO2-enriched ammoniated solution having passed through the third absorption stage. Final Act. 5–6. The Examiner finds that Gal teaches that the CO2 capture system effectiveness for removing CO2 from a flue gas depends upon the ionic solution temperature and mole ratio (R) of NH3 to CO2 in the solution. Id. at 6 (citing Gal ¶ 17). The Examiner further finds that Gal configures each absorption stage to carry out a particular phase of the CO2 absorption process. Id. (citing Gal ¶ 47). The Examiner determines that a person of ordinary skill in the art would have been motivated to use a mixture of CO2-lean ammoniated solution and a first and second portion of the recirculated CO2-enriched ammoniated solution having passed through the third absorption stage in the second absorption stage of the CO2-absorber in order to achieve a desired R- Appeal 2020-003398 Application 14/193,052 6 value for the ionic solution used in the second stage for desired CO2 removal and ammonia slip in the second absorption stage. Id. at 7. The Examiner determines that there would have been motivation to do so because the R- value of the ionic solution is a result effective variable relative to its CO2 removal effectiveness and ammonia slip. Ans. 7. Appellant argues that Gal does not teach contacting a flue gas with a mixture of a first portion and second portion of the recirculated CO2- enriched ammoniated solution in a second stage. Appeal Br. 13. Appellant also argues that it would not have been obvious to a person of ordinary skill in the art to modify Gal to adjust the R-value to increase CO2 absorption efficacy by providing a first portion of a recirculated CO2- enriched ammoniated solution between a second and a third absorption stage. Appeal Br. 14. Appellant’s arguments are not persuasive of reversible error. Gal supports the Examiner’s finding that R is a result-effective variable. Gal teaches that a decrease in R value corresponds to a decrease in the effectiveness of the ionic solution in capturing CO2 from the flue gas stream,that R can be controlled by controlling the amount of ammonium in the ionic solution, and that capture system effectiveness depends upon the ionic solution temperature and the R-value. Gal ¶¶ 16–19. In each absorption phase, Gal controls the R-value by adjusting the ionic solution temperature, ammonia vapor pressure, or both. Id. ¶¶ 49–52. Although Gal does not explicitly teach adjusting the R-value specifically by modifying the system to provide an additional stream of recirculated CO2-enriched ammoniated solution between the second and the third absorption stages (see Appeal Br. 13–14), Gal’s teaching that each stage has a different CO2 concentration and ammonia concentration, and teaching of R as the Appeal 2020-003398 Application 14/193,052 7 ammonia to CO2 mole ratio, would have suggested to a person of ordinary skill in the art that modifying Gal by introducing an additional stream of recirculated CO2-enriched ammoniated solution in the second absorption stage would optimize the R-value and improve the capture system’s effectiveness. Accordingly, we find that a preponderance of evidence supports the Examiner’s determination that claim 1 is obvious over Gal. Appellant does not present separate arguments directed to dependent claims 2, 3, 5–12, 14, and 15, and therefore those claims fall with claim 1. Obviousness of claim 4 over the combination of Gal and Dube Claim 4 depends from claim 1 and additionally recites the recirculated CO2-enriched ammoniated solution and the CO2- lean ammoniated solution are kept at a temperature, while passing through the first and second absorption stages, which is above a temperature at which ammonium bicarbonate particles may start to precipitate from the respective ammoniated solution Appeal Br. 20. The Examiner acknowledges that Gal does not explicitly teach maintaining the temperature of the CO2-enriched and lean ammoniated solutions above the temperature at which ammonium bicarbonate particles may start to precipitate, but finds that Dube teaches temperature dependency of the formation of solid ammonium bicarbonate and undesirability of ammonium bicarbonate solids that may plug the absorption column and result in deterioration of system performance. Final Act. ¶¶ 41–42 (citing Dube ¶¶ 10, 13). The Examiner determines it would have been obvious to maintain the solutions of Gal’s process at a Appeal 2020-003398 Application 14/193,052 8 temperature above which ammonium bicarbonate particles would start to precipitate, in order to avoid deterioration of system performance. Appellant argues that a person of ordinary skill in the art would not have been motivated to modify Gal as proposed by the Examiner, because Gal discloses that the absorber vessel may be configured to provide for collection of the ionic solution at the bottom of the vessel and separation and removal of solids that have formed within the ionic solution by means of a hydrocyclone. Appeal Br. 15–16 (citing Gal ¶ 58). Appellant further argues that a person of ordinary skill in the art would not have been led to modify Gal’s system, which is directed at removing solids, by looking at Dube’s system, which is directed at preventing solids. Id. at 16. Appellant’s argument is not persuasive of reversible error. Gal’s teaching of a hydrocyclone for removal of solids at the bottom of the absorption vessel also teaches, like Dube, the undesirability of solids in the absorption column. See Gal ¶ 58. Appellant’s argument addresses the references individually and does not rebut the Examiner’s showing that Dube’s teaching would have led a person of ordinary skill to modify Gal to prevent formation of ammonium bicarbonate precipitates. Accordingly, we affirm the rejection of claim 4. Obviousness of claim 13 over the combination of Gal and Park Claim 13 depends from claim 1 and additionally recites specific liquid to gas ratios of solution to flue gas, L/G, in the first and second absorption stages. Appeal Br. 22. The Examiner acknowledges that Gal does not explicitly teach liquid to gas ratios in the first and second absorption stages, but finds that Park teaches that absorption of CO2 is directly related to the contact time of the flue gas and absorbent, and closely related to the specific Appeal 2020-003398 Application 14/193,052 9 surface area of the packing material. Final Act. ¶ 47 (citing Park 250). The Examiner further finds that Park teaches flue gas flow rate should be inversely proportional to absorbent flow rate and that both rates should be adjusted to prevent absorbent flooding. Id. The Examiner further finds that the L/G ratio is a result effective variable relative to CO2 removal efficiency. Id. (citing Park 250, Fig. 4). The Examiner determines it would have been obvious to a person of ordinary skill in the art to vary the L/G ratio in each absorption stage of Gal’s process to within the claimed ranges in order to achieve the desired CO2 removal in each stage of the absorber with a reasonable expectation of success. Id. ¶ 48. Appellant argues that the Examiner fails to explain how knowing that the flow rate may affect CO2 absorption would lead a person of ordinary skill in the art to the specific flow rates recited in claim 13. Appeal Br. 17. Appellant’s argument is not persuasive of reversible error. Appellant does not dispute that the L/G ratio is a result effective variable relative to CO2 removal efficiency, and offers no evidence why a person of ordinary skill in the art would have been unable to achieve the recited L/G ratios through routine optimization. Accordingly, we affirm the rejection of claim 13. CONCLUSION The Examiner’s rejections are affirmed. Appeal 2020-003398 Application 14/193,052 10 DECISION SUMMARY Claim(s) Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 1–3, 5–12, 14, 15 103 Gal 1–3, 5–12, 14, 15 4 103 Gal, Dube 4 13 103 Gal, Park 13 Overall Outcome 1–15 AFFIRMED