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
Claims 7-16 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Group II, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 26 March 2026.
Summary
This is a non-final office action for application 18/481,669, filed on 05 October 2023, and is in response to Applicant’s election of Group I, claims 1-6, filed on 26 March 2026, which was a reply to an election/restriction requirement dated 12 March 2026. Accordingly, claims 1-6 are under full consideration.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1-3 and 5 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Vaidya et al. (US-20200360855-A1), hereinafter “Vaidya”.
Regarding Claim 1, Vaidya discloses a system for generating a concentrated H2S stream (hydrogen sulfide recovery; see [0008]) from feed gas (sweetening a syngas stream; see [0009]), the system comprising: an amine gas removal unit configured to receive a gas stream (supplying a syngas stream to a nonselective amine absorption unit; see [0009]), wherein the amine gas removal unit is further configured to remove hydrogen sulfide gas and carbon dioxide gas from a gas stream to yield an acid gas stream (separating the syngas stream… to obtain an overhead syngas stream and an acid gas stream… the acid gas stream having hydrogen sulfide and carbon dioxide; see [0009]); a first compressor coupled to the amine gas removal unit and configured to compress the acid gas stream to yield a high pressure acid gas stream acid gas stream 412 obtained from processing in nonselective amine absorption unit… acid gas stream 412 is compressed; see [0065]); and a CO2 permeable membrane (membrane separation unit 420 can have at least one carbon dioxide-selective membrane; see [0066]) coupled to the compressor (compressed and sent to membrane separation unit 420; see [0065]), wherein the CO2 permeable membrane is configured to separate the high pressure acid gas stream (membrane separation unit 420 separates the acid gas stream 412; see [0066]) into a CO2 rich stream that is enriched in CO2 compared to the high pressure acid gas stream (separates the acid gas stream to obtain hydrogen sulfide-stripped stream 422; see [0066] and hydrogen sulfide-stripped stream 422 can contain carbon dioxide; see [0067]) and an H2S rich stream that is enriched in H2S compared to the high pressure acid gas stream (membrane separation unit separates the acid gas stream to obtained enriched hydrogen sulfide stream 421; see [0066]). Although Vaidya identifies the feed gas as syngas, claim 1 is directed to a system, and the recitation that the feed gas is natural gas does not impose any structural limitation on the recited amine gas removal unit, compressor, or membrane. The claimed system is structurally indistinguishable from the system disclosed by Vaidya.
Regarding Claim 2, Vaidya discloses the system of claim 1, wherein the amine gas removal unit comprises an aqueous alkylamine solution (a liquid solvent for selectively removing acid gas components from syngas can be used in an absorption process; see [0034] and some nonselective amine absorption processes can involve using MEA; see [0037]).
Regarding Claim 3, Vaidya discloses the system of claim 2, wherein the aqueous alkylamine solution comprises at least one of monoethanolamine, diethanolamine, or methyldiethanolamine (some nonselective amine absorption processes can involve using MEA; see [0037]).
Regarding Claim 5, Vaidya discloses the system of claim 1, further comprising a sulfur recovery unit coupled to the CO2 permeable membrane and configured to recover sulfur from the H2S rich stream (the enriched hydrogen sulfide stream 421 can be entirely processed in the Claus plant of a sulfur recovery unit; see [0066]).
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.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Vaidya et al. (US-20200360855-A1), hereinafter “Vaidya”, in view of Mudaibegh et al. (Feed gas quality limits acid gas removal unit capacity), hereinafter “Mudaibegh”.
Regarding Claim 4, Vaidya discloses the system of claim 1. Vaidya does not explicitly teach a slug catcher. However, Mudaibegh discloses a slug catcher configured to receive a gas feed stream (sour gas feed streams… enter the Plant A inlet area, which consists of three parallel slug catchers; see Para. 3) and coupled to an amine gas removal unit (sour gas from the slug catchers is fed to two identical AGRUs… The AGRU used formulated MDEA; see Para. 4).
Vaidya and Mudaibegh are both considered to be analogous to the claimed invention because they are in the same field of acid gas recovery. Modifying Vaidya by incorporating the slug catcher of Mudaibegh would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention because Mudaibegh offers the motivation of separating accumulated water and hydrocarbon liquids from the sour gas feed (see Para. 3).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Vaidya et al. (US-20200360855-A1), hereinafter “Vaidya” in view of Baker et al. (US-5558698-A), hereinafter “Baker”.
Regarding Claim 6, Vaidya discloses the system of claim 1, but does not explicitly teach a second compressor coupled to the membrane. However, Baker discloses a compressor coupled to the CO2 permeable membrane (the permeate streams 25 and 28 from the two steps of the first stage are combined as stream 29 to be recompressed in compressor 30; see Col. 20 Lines 15-17 and Fig. 7 Parts 23, 26, 25, 28, and 30) and configured to compress the H2S rich stream to yield a compressed H-2S rich stream (the hydrogen-sulfide concentrated permeate stream; see Col. 10 Line 67-Col. 11 Line 1 – This shows that the permeate streams 25 and 28 that are being compressed in compressor 30 are hydrogen-sulfide rich streams).
Vaidya and Baker are both considered to be analogous to the claimed invention because they are in the same field of acid gas recovery. This modification would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention because Baker offers the motivation of enabling recompression of the streams (see Col. 20 Line 17). Further, compressors were/are well known for increasing and controlling the pressure of process gas streams to satisfy downstream process requirements. Incorporating a compressor would have merely employed a known device according to its established function to obtain the predictable result of delivering the H2S rich stream at a desired operating pressure for subsequent processing, transport, or recovery.
Conclusion
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/A.L.K./Examiner, Art Unit 1774
/CLAIRE X WANG/Supervisory Patent Examiner, Art Unit 1774
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