Ex Parte Howard

Patent Trial and Appeal BoardApr 10, 2015

11716493 (P.T.A.B. Apr. 10, 2015)

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. 11/716,493 03/09/2007 Henry Edward Howard 21682 7008 27182 7590 04/10/2015 PRAXAIR, INC. LAW DEPARTMENT - M1-04 39 OLD RIDGEBURY ROAD DANBURY, CT 06810-5113 EXAMINER PETTITT, JOHN F ART UNIT PAPER NUMBER 3744 MAIL DATE DELIVERY MODE 04/10/2015 PAPER 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. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________________ Ex parte HENRY EDWARD HOWARD ____________________ Appeal 2013-001375 Application 11/716,493 Technology Center 3700 ____________________ Before JENNIFER D. BAHR, LYNNE H. BROWNE, and BRANDON J. WARNER, Administrative Patent Judges. BAHR, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Henry Edward Howard (Appellant) appeals under 35 U.S.C. § 134 from the Examiner’s decision rejecting claims 1–4 and 6.1 We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. 1 Claims 5 and 7–17 have been withdrawn from consideration. Non-Final Act. 1. Appeal 2013-001375 Application 11/716,493 THE CLAIMED SUBJECT MATTER Claim 1, reproduced below, is representative of the claimed subject matter. 1. A method of separating a gaseous mixture comprising nitrogen and oxygen to produce a nitrogen product, said method comprising: introducing a purified, pressurized and cooled gaseous stream into a rectification column to produce an overhead nitrogen-rich vapor and an oxygen-enriched liquid bottoms; depressurizing a first oxygen-enriched liquid stream composed at least in part of the oxygen-enriched liquid bottoms, partially vaporizing the first oxygen-enriched liquid stream within a first heat exchanger, disengaging a vapor phase from a liquid phase formed by the partial vaporization of the first oxygen-enriched liquid stream, depressurizing a second oxygen-enriched liquid stream composed at least in part of the liquid phase and partially vaporizing the second oxygen- enriched liquid stream through indirect heat exchange with at least a portion of a vapor phase stream composed of the vapor phase within a second heat exchanger, thereby substantially condensing at least a portion of the vapor phase stream to form a nitrogen-rich liquid stream; condensing a first part of a column overhead nitrogen- rich stream composed of the overhead nitrogen-rich vapor in the first heat exchanger, condensing a second part of the overhead nitrogen-rich stream in a third heat exchanger through indirect heat exchange with the second oxygen-enriched liquid stream after having been partially vaporized, thereby further vaporizing the second oxygen-enriched liquid stream, and returning at least part of the condensed column overhead nitrogen-rich stream to the rectification column as reflux; introducing at least part of the nitrogen-rich liquid stream into the rectification column, above the purified, pressurized and cooled gaseous stream; and producing a product nitrogen stream from part of the overhead nitrogen-rich vapor. 2 Appeal 2013-001375 Application 11/716,493 EVIDENCE The Examiner relied on the following evidence in rejecting the claims on appeal: Cormier Rathbone Mostello US 3,967,464 US 5,551,258 US 6,330,812 B2 July 6, 1976 Sept. 3, 1996 Dec. 18, 2001 REJECTIONS2 Claims 1, 4, and 6 stand rejected under 35 U.S.C. § 103(a) as unpatentable over Rathbone and Cormier. Claims 2 and 3 stand rejected under 35 U.S.C. § 103(a) as unpatentable over Rathbone, Cormier, and Mostello. OPINION Claim 1 The Examiner found that Rathbone discloses a method satisfying all the limitations of claim 1, “but does not explicitly teach that the column (120, 154) must be a single integrated unit but rather teaches that the column (120, 154) is formed from two separate structures (see figures, 120, 154 are separate structures).” Ans. 5–7. However, the Examiner found that Cormier evidences that it was well known to install distillation systems as a united column structure. Ans. 7 (citing Cormier, col. 5, ll. 25–30; Figs. 1, 2, columns 102 and 104 united as column 100). Thus, the Examiner determined it would have been obvious “to mount the columns of Rathbone 2 The Examiner withdrew the rejection of claims 1, 4, and 6 under 35 U.S.C. § 102(b) as anticipated by Rathbone and the rejection of claims 2 and 3 under 35 U.S.C. § 103(a) as unpatentable over Rathbone and Cormier. Ans. 4. 3 Appeal 2013-001375 Application 11/716,493 together to form an integrated column as taught by Cormier” to reduce required floor space for the distillation system and to reduce line length between sections (columns 120, 154) to lower heat loss. Ans. 7. Appellant maintains that, even with the modification of Rathbone proposed in the rejection, the Examiner erred in considering Rathbone’s two columns (higher pressure column 120 and lower pressure column 154) to be “a rectification column—a single entity.” Reply Br. 9, 14–15. This line of argument is not convincing, for the reasons articulated by the Examiner on page 10 of the Non-Final Action, mailed December 22, 2011. Appellant fails to direct us to any evidence showing that the terminology “rectification column” has acquired a particular meaning in the art that precludes the Examiner’s interpretation. Moreover, the Examiner’s interpretation appears to be consistent with Appellant’s Specification, which expressly contemplates that “[r]ectification column 14 could be split into multiple sections,” and with Cormier’s reference to “an integral dual pressure distillation column having a high pressure column 102 and a low pressure column 104 separated by a reflux-condenser 106.” Spec., para. 49; Cormier, col. 5, ll. 27–29; Non-Final Act. 10. Appellant additionally contends that “there would be no suggestion to combine the two columns into a single column integrated unit” because, unlike Cormier’s high and low pressure columns, which are connected in a heat transfer relationship by means of a condenser reboiler located in the bottom of the low pressure column, Rathbone’s higher pressure and lower pressure columns are connected in a heat transfer relationship via condenser 132, which is not located in the bottom of the low pressure column. Reply Br. 15. Further, Appellant contends that it is “not clear how this would even 4 Appeal 2013-001375 Application 11/716,493 be done or how any advantage of this would be derived given the other external heat exchangers of Rathbone, namely 133, 135 and 150, that are used in condensing reflux to the columns.” Reply Br. 15. These arguments were not presented in the Appeal Brief and thus are not entitled to consideration by the Board. 37 C.F.R. § 41.37 (c)(1)(iv) (2014) (providing that “any arguments or authorities not included in the appeal brief will be refused consideration by the Board for purposes of the present appeal”). In any event, Appellant’s identification of differences between the connections between Cormier’s high pressure and low pressure columns and Rathbone’s columns does not demonstrate a reason why a person having ordinary skill in the art would have been dissuaded from or incapable of re-directing the lines to mount Rathbone’s higher pressure column 120 and lower pressure column 154 together to form an integrated column to reduce required floor space. Appellant also argues that none of the streams (at inlets 126, 122, and 166, or just 126) relied upon by the Examiner satisfies the limitation of introducing “a purified, pressurized and cooled gaseous stream into a rectification column” recited in claim 1. Reply Br. 12; see Ans. 5. In particular, Appellant contends that, because the streams introduced at inlets 126 and 122 have been “fully or partially condensed,” they are not a “gaseous stream.” Reply Br. 12; see Rathbone, col. 11, ll. 35–48 (discussing introducing air streams that have been “at least partially condensed” at inlets 122 and 126). This argument is not convincing. A stream that has been partially condensed retains a vapor, or gaseous, component, and, thus, is a “gaseous stream.” Furthermore, Appellant acknowledges that the stream 5 Appeal 2013-001375 Application 11/716,493 introduced into lower pressure column 154 (via expander 112) at inlet 166 “is a gas when it is introduced into a column.” Reply Br. 12. Appellant also argues that Rathbone fails to disclose the step of condensing a second part of the overhead nitrogen-rich stream in a third heat exchanger through indirect heat exchange with the second oxygen-enriched liquid stream after having been partially vaporized, as called for in claim 1. Reply Br. 14. More specifically, Appellant contends that although “intermediate reboiler 132 acts to condense an overhead nitrogen-rich stream[,] it does not do so through indirect heat exchange with any second oxygen-rich stream.” Reply Br. 14. This argument is not convincing. Appellant concedes that the stream that exits from Rathbone’s fourth condenser 150 (corresponding to the claimed second heat exchanger) after being depressurized at valve 158 is a partially-vaporized second oxygen- enriched liquid stream. Reply Br. 13. This stream then enters lower pressure column 154 at inlet 160 and then is separated into nitrogen, which is obtained at the top of column 154, and impure oxygen, which descends to the bottom of column 154. Rathbone, col. 12, ll. 46–50. The descending flow of liquid then passes through reboiling passages of condenser 132, where it is partially or totally reboiled, and the overhead nitrogen-rich stream “is condensed by indirect heat exchange with” the descending flow of boiling liquid. Rathbone, col. 11, ll. 58–62; col. 12, ll. 56–60. Appellant provides no explanation as to why this fails to satisfy the requirement in claim 1 that the overhead nitrogen-rich stream be condensed in a third heat exchanger through indirect heat exchange with the second oxygen-enriched liquid stream. 6 Appeal 2013-001375 Application 11/716,493 For the above reasons, Appellant’s arguments fail to apprise us of error in the rejection of claim 1. Accordingly, we sustain the rejection of claim 1 as unpatentable over Rathbone and Cormier. Claims 4 and 6 Appellant’s argument contesting claims 4 and 6 is premised on Appellant’s unconvincing contention that Rathbone’s higher pressure column 120 and lower pressure column 154 cannot together form a rectification column. See Reply Br. 17; Appeal Br. 16. Thus, Appellant also fails to apprise us of error in the rejection of claims 4 and 6. Accordingly, we sustain the rejection of claims 4 and 6 as unpatentable over Rathbone and Cormier. Claim 2 In contesting the rejection of claim 2 as unpatentable over Rathbone, Cormier, and Mostello (see Ans. 7–9), Appellant contends that in the combination of Rathbone, Cormier, and Mostello proposed by the Examiner, “there is no vaporized fraction of a ‘second oxygen-enriched liquid stream after having been further vaporized[’] to engage in any subcooling heat exchange duty in the first instance.” Reply Br. 19–20; Appeal Br. 18. The basis of Appellant’s contention is that “the stream 208 results from a vaporized, phase separated liquid stream 121 and a vapor phase stream 206 and not, a second oxygen-enriched liquid stream that has been partially and the [sic] further vaporized as called for in the claims.” Reply Br. 19; Appeal Br. 18. Appellant’s observation about the makeup of stream 208 of Mostello does not apprise us of error in the Examiner’s findings regarding Mostello or the Examiner’s reasoning in support of the conclusion of obviousness. See Ans. 9. Mostello’s second oxygen-enriched liquid stream 204 is vaporized 7 Appeal 2013-001375 Application 11/716,493 in condenser 34 to form vapor phase stream 205, which, thus, is a vaporized fraction of second oxygen-enriched liquid stream 204, and stream 205 is further vaporized in condenser 31 before being fed into stream 208. Mostello, Fig. 2. We sustain the rejection of claim 2 as unpatentable over Rathbone, Cormier, and Mostello. Claim 3 In contesting the rejection of claim 3, Appellant simply reiterates that in the combination of Rathbone, Cormier, and Mostello “there is no ‘waste stream’ formed from a ‘second oxygen-enriched liquid stream that has been partially vaporized and then further vaporized.” Reply Br. 20; Appeal Br. 19. Once again, this argument fails to apprise us of error in the Examiner’s findings regarding Mostello or the Examiner’s reasoning in support of the conclusion of obviousness. We sustain the rejection of claim 3 as unpatentable over Rathbone, Cormier, and Mostello. DECISION The Examiner’s decision rejecting claims 1–4 and 6 is affirmed. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv). AFFIRMED mls 8