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 .
Response to Amendment
Applicant’s amendment filed 15 July 2026 have been considered. It is acknowledged that claims 1 and 4 are amended, and claims 2 and 5 are cancelled by Applicant. Accordingly, claims 1, 3-4, and 6 are under full consideration. Further, by way of amendment, the 35 U.S.C. 112 rejections of claims 1-6 are withdrawn.
Response to Arguments
Applicant’s arguments filed 15 July 2026, with respect to the rejection of amended claim 1 under Rameshni et al. (US-20170044015-A1), hereinafter “Rameshni”, in view of Herb et al. (US-7510696-B2), Grover (US-8124049-B2) have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new grounds of rejection is made in view of Hakka et al. (US-7056482-B2), hereinafter “Hakka”.
Applicant argues that the use of CO2 as an alternative to the colled effluent of Rameshni would render Rameshni unsatisfactory for its intended purpose. However, Applicant has not provided evidence establishing that the proposed modification would prevent Rameshni from achieving is intended objective. Rather, Applicant merely describes the disposition of the cooled effluent within Rameshni and concludes, without evidentiary support, that substitution with CO2 would destroy the intended purpose of the process. Such unsupported attorney argument is not evidence.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
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.
Claims 1 and 4 are rejected under 35 U.S.C. 103 as being unpatentable over Rameshni et al. (US-20170044015-A1), hereinafter “Rameshni”, in view of Herb et al. (US-7510696-B2), Grover (US-8124049-B2), and Hakka et al. (US-7056482-B2), hereinafter “Hakka”.
Regarding Claim 1, Rameshni discloses a fire suppression system (cooled first stage; see [0053]) for sulfur recovery unit converter system (processes for recovering sulfur; see [0027]), comprising: a gas sweetening unit configured to provide an off gas (outlet gas then goes… in the quench system and to the tail gas amine section… and the acid gas from the regeneration overhead is recycled back to the front; see [0049]), a quench line configured for delivering an off gas into a feed line of the sulfur recovery unit converter system (cooled first stage effluent recycled to the inlet of the first stage to control temperature rise; see [0043]); an oxidation air inlet configured for feeding an oxidation air to an oxidation air preheater (see Fig. 1, stream 22), the oxidation air preheater configured to provide a heated oxidation air to the feed line (see Fig. 3-3a, air stream 22 and heater 1); a feed preheater configured for receiving the heated oxidation air, the CO2 rich off gas, a process gas, or a combination thereof (see Fig. 3-3a, heater 1); a selective oxidation converter disposed downstream of the feed preheater (flows to the reheater then… flows to a direct oxidation reactor… direct oxidation catalyst types are Selectox; see [0124]), the selective oxidation converter configured for producing a converter effluent (see Fig. 3-3a, effluent stream leaving part 2); an off gas control valve disposed in the quench line and configured for controlling the off gas to the selective oxidation converter (overhead gas from the regenerator stream 70 is recycled to the front; see [0110] and Fig. 1-1C, control valve in stream 70); wherein, the off gas is used for quenching (the cooling load is adjusted to control the overhead gas temperature; see [0110]). The limitation claiming that the quench stream is used to suppress a potential fire, and cooling preheaters and a selective oxidation converter when temperature exceeds normal operating limits or fire is suspected is a functional limitation that does not further limit the structure of the apparatus, but merely sets forth a manner of operating the apparatus. The Courts have held that apparatus claims must be structurally distinguishable from the prior art in terms of structure, not function. See In re Danley, 120 USPQ 528, 531 (CCPA 1959); and Hewlett-Packard Co. V. Bausch and Lomb, Inc., 15 USPQ2d 1525, 1528 (Fed. Cir. 1990) (see MPEP §§ 2114 and 2173.05(g)). The manner of operating an apparatus does not differentiate an apparatus claim from the prior art, if the prior art apparatus teaches all of the structural limitations of the claim. See Ex Parte Masham, 2 USPQ2d 1647 (BPAI 1987). Functional limitations that do not limit the structure need not be given further due consideration in determining patentability of an apparatus.
Rameshni does not explicitly teach the quench stream being CO2 rich. However, Herb discloses the introduction of CO2 as a cooling or quenching medium (introducing an oxidative stream comprising CO2 with the gaseous stream… wherein the oxidative stream is derived from a product stream of the shift reactor preferably after cooling… or from enriched CO2 streams from CO-2 separation units; see Col. 4 Lines 28-35).
Rameshni and Herb are both considered to be analogous to the claimed invention because they are in the same field of elemental gas recovery/production. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify Rameshni by incorporating the teachings of Herb and introducing a cooled CO2 rich stream. Doing so would prevent over reduction of catalyst (see Herb, Col. 5 Lines 19-22). Additionally, Grover discloses that using CO2 in a gas recovery system also has the benefit increasing thermal efficiency (see Grover, Col. 2 Lines 34-36).
Further, the limitation requiring the quench line be configured for delivering a “CO2 rich off gas” is directed to the composition of the working fluid and does not impose structural differences on the claimed system. The recited quench line and associated components are not structurally modified by the identity of the gas, and the prior art systems configured to deliver quench or cooling gas would inevitably be capable of delivering CO2. Substituting CO2- for other known quench gases (e.g. inert or recycle gases) represents a predictable use of known alternatives and does not confer patentable weight absent evidence of criticality.
Regarding the limitation claiming, the CO2 rich off gas “comprises at least 95 mol% CO2 and at least 4 mol% water”, Hakka discloses that CO2 exiting an amine treatment, which is analogous to a gas sweetening unit, comprises water saturated CO2 (see Col. 14 Lines 53-55). While Hakka does not explicitly teach the exact claimed composition, it is understood that the structure of the apparatus disclosed by Hakka is sufficient to process/handle varying compositions of water and CO2, as the composition of the stream is dependent on operating conditions in the system. MPEP 2144.05.II states that “[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation”. Rameshni and Hakka are both considered to be analogous to the claimed invention because they are in the same field of sour gas treatment. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to incorporate the teachings of Hakka into modified Rameshni by manipulating operating conditions to achieve a specific composition. Doing so is a matter of routine experimentation. Further, as explained, the specific claimed composition is a consequential limitation resulting from a functional limitation requiring specific operating conditions, and does not further define the structure of the apparatus. The Courts have held that apparatus claims must be structurally distinguishable from the prior art in terms of structure, not function. See In re Danley, 120 USPQ 528, 531 (CCPA 1959); and Hewlett-Packard Co. V. Bausch and Lomb, Inc., 15 USPQ2d 1525, 1528 (Fed. Cir. 1990) (see MPEP §§ 2114 and 2173.05(g)). The manner of operating an apparatus does not differentiate an apparatus claim from the prior art, if the prior art apparatus teaches all of the structural limitations of the claim. See Ex Parte Masham, 2 USPQ2d 1647 (BPAI 1987). Functional limitations that do not limit the structure need not be given further due consideration in determining patentability of an apparatus.
Regarding Claim 4, the limitations of this claim do not exceed those of claim 1, with the exception of the preamble of claim 4 reciting a “purge system” as opposed to the “quench system” recited in claim 1. Calling this system a purge system, however, is not limiting as the structure claimed in claim 4 is identical to that of claim 1. Accordingly, please refer to the claim 1 rejection as the rejection of claim 4 follows the same rationale.
Claims 3 and 6 are rejected under 35 U.S.C. 103 as being unpatentable over Rameshni et al. (US-20170044015-A1), hereinafter “Rameshni”, in view of Herb et al. (US-7510696-B2), Grover (US-8124049-B2), Hakka et al. (US-7056482-B2), hereinafter “Hakka”, and Srinivas et al. (US-20030194366-A1), hereinafter “Srinivas”.
Regarding Claim 3, Rameshni, Herb, Grover, and Hakka together disclose the system of claim 1. Rameshni further discloses a condenser configured for separating a liquid sulfur product and a tail gas from the converter effluent (condensers to condense and recover elemental sulfur from the product gas stream; see [0083]), wherein the tail gas stream is routed to a thermal oxidizer (“ tail gas stream from the last condenser flows to the tail gas unit consists of SuperSulf reactor, quench system, and the selective amine type in the amine tail gas unit where the absorber…; see [0090] and “tail gas from the quench column flows into the amine absorber”; see [0109] then “treated tail gas from the absorber is sent to the incinerator… compounds in this gas stream are oxidized”; see [0113]).
Rameshni does not explicitly teach bypass. However, Srinivas discloses a bypass control valve configured for diverting a process gas to the converter effluent (the inlet line is provided with an optional bypass where a selected portion of the sour gas can be diverted past the oxidation reactor. The bypass line rejoins the gas stream exiting the oxidation process; see [0125]). When modifying Rameshni with the teachings of Srinivas, it would naturally follow that the bypass control valve diverts the process gas from a location upstream of the quench line because Rameshni discloses the quench line being used to control temperature rise (see [0043]), indicating operation separate from the operation of other process gases. A person of ordinary skill in the art before the effective filing date of the claimed invention would understand that if the bypass control valve were not placed upstream of the quench line, the quench line operation would be dependent on the process gas operation, which reduces the quench gas ability to effectively control temperature rise, which is the stated function of the quench gas stream (see Rameshni [0043]).
Rameshni and Srinivas are both considered to be analogous to the claimed invention because they are in the same field of sulfur recovery. Therefore, it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify Rameshni by incorporating the teachings of Srinivas and providing a bypass. Doing so would enable the adjustment of the H2S to SO2 ratio (see Srinivas [0126]).
Regarding Claim 6, Rameshni, Herb, Grover, and Hakka together disclose a system of claim 4. The remaining limitations of claim 6 do not exceed those of claim 3. Please refer to the claim 3 rejection as the rejection of claim 6 follows the same rationale.
Conclusion
Applicant's amendment necessitated 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 ALYSSA LEE KUYKENDALL whose telephone number is (571)270-3806. The examiner can normally be reached Monday- Friday 9:00am-5:00pm.
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/A.L.K./Examiner, Art Unit 1774
/CLAIRE X WANG/Supervisory Patent Examiner, Art Unit 1774
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