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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on February 9, 2026 has been entered.
Response to Arguments
Applicant's arguments filed on February 9, 2026 have been fully considered.
Applicant notes that in Martella and Deane, the pressure difference between the entrance of the continuous gas line and the exit of the continuous gas line is Δp = 0 (arguments on page 12, last paragraph, to page 13, last paragraph). Thus, Martella and Deane, taken alone or in further view of secondary references, fail to disclose or adequately suggest the new limitation in amended claim 12 (at lines 23-26), wherein “the compressor is capable of increasing the system pressure within the continuous gas line to achieve a higher pressure at the exit of the continuous gas line than at the entrance of the continuous gas line by using the energy released during the methanation process”. Therefore, the rejections under 35 U.S.C. §102 and §103 as set forth in the previous Office action have been withdrawn.
However, upon further consideration, a new ground of rejection is made in view of the newly discovered prior art reference to Zuberbuehler et al. (WO 2011/076315 A2), as detailed in the rejections, below.
Claim Rejections - 35 USC § 112
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.
Claims 12-15 and 20 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.
Regarding claim 12, the limitation “wherein the compressor of the at least one turbocharger is located in the continuous gas line at a position located between the entrance of the continuous gas line and the entry of the methanation reactor or between the exit of the methanation and the exit of the continuous gas line” (at lines 19-22) is unclear.
Firstly, the limitation is unclear because claim previously set forth that “the compressor of the at least one turbocharger is connected with the continuous gas line, and is arranged in a section of the continuous gas line which defines a path from the introduction of the starting material to the removal of the methane-enriched gas, upstream, between, or downstream of the methanation reactor(s).” The limitation appears to exclude the location “between” the methanation reactors of a multi-stage methanation process.
Secondly, the limitation recites “the methanation reactor” (twice, at lines 21 and 22), which refers to a single methanation reactor. However, the claim previously set forth “one methanation reactor each for the at least one single-stage or multi-stage methanation process” (at lines 4-5), which scope includes one or a plurality of the methanation reactors.
The remaining claims are also rejected because they depend from a rejected base claim.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 12, 13, and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Zuberbuehler et al. (WO 2011/076315 A2) in view of Prestel (DE 10 2004 059 315 A1) and Pipeline Safety Trust (Pipeline Briefing Paper #2).
Regarding claim 12, Zuberbuehler et al. discloses a system (see FIG. 1; translation) for the production of methane-enriched gas (i.e., a final product gas comprising a methane-rich product gas formed by a process represented by equations 1, 2, and 3; see translation at page 3, top of page) from hydrogen and carbon-containing starting material (i.e., a reactant gas comprising hydrogen, carbon dioxide, and minor proportions of carbon monoxide, methane, and other gases; see translation at page 2, last paragraph, to page 3, first paragraph) in at least one single-stage or multi-stage methanation process, the system comprising:
one methanation reactor for the at least one single-stage or multi-stage methanation process (i.e., methanation reactors R1 and R2, respectively, for a two-stage methanation process; or methanation reactors R1, R2, and R3, respectively, for a three-stage methanation process; as shown), wherein each methanation reactor R1, R2, R3 comprises an entry for the introduction of feed gas, which comprises the hydrogen and carbon-containing starting materials or a methane-enriched gas from a previous methanation stage, and an exit for the methane-enriched product gas;
a continuous gas line having an entrance (i.e., at point E) for the introduction of the hydrogen and carbon-containing starting material, and an exit (i.e., at point A for the two-stage methanation process; or at point A3 for the three-stage methanation process) for the removal of the methane-enriched gas from the system; and
a plurality of compressors 7.1, 7.2 and a plurality of controllable throttling devices 9.1, 9.2, 9.3;
wherein the compressors 7.1, 7.2 are connected with the continuous gas line and are arranged in a section of the continuous gas line which defines a path from the introduction of the starting material to the removal of the methane-enriched gas, upstream, between, or downstream of the methanation reactors R1, R2, R3; and
wherein the compressors 7.1, 7.2 are located in the continuous gas line at a position located between the entrance E of the continuous gas line and the entry of the methanation reactor (i.e., the compressor 7.1 is located between point E and the inlet to the reactor R1; and the compressor 7.2 is located between point E and the inlet to the reactor R2) or between the exit of the methanation reactor and the exit A, A3 of the continuous gas line (i.e., the compressor 7.2 is located between the exit of the reactor R1 and the point A, A3).
Zuberbuehler et al. further discloses that the compressors are capable of increasing the system pressure within the continuous gas line (i.e., the compressor 7.1 increases the pressure of the reactant gas received from point E to a predetermined higher pressure, and the compressor 7.2 increases the pressure of the product gas from the reactor R1 to a predetermined higher pressure; see, e.g., translation at page 4, last paragraph).
Zuberbuehler et al. further discloses that the controllable throttling devices are capable of decreasing the system pressure within the continuous gas line (i.e., the controllable throttling device 9.1 decreases the pressure of the product gas removed from the reactor R1 by throttling/expanding the gas to a predetermined lower pressure; the controllable throttling device 9.2 decreases the pressure of the product gas removed from the reactor R2 by throttling/expanding the gas to a predetermined lower; and the controllable throttling device 9.3 decreases the pressure of the product gas removed from the reactor R3 by throttling/expanding the gas to a predetermined lower pressure).
Zuberbuehler et al. (see translation at page 4, fifth paragraph) further discloses,
“… an energy expenditure associated with the methanation depends on the setting of the at least one parameter, wherein the change in setting made reduces the energy expenditure. Thus, an energy-optimized procedure is achieved with constant product quality, with the energy expenditure considered here being, for example, the energy consumption associated with the compression of gases (compression) or the addition of water and its treatment and / or discharge of water from the gas.” (with emphasis added).
Therefore, Zuberbuehler et al. sought to minimize the energy expenditure of the methanation process, such as the energy consumption associated with the compression of the gases in the continuous gas line by the compressors 7.1, 7.2.
Zuberbuehler et al., however, fails to disclose that the system comprises at least one turbocharger comprising a compressor and a turbine mechanically connected by a common shaft, whereby the compressor is capable of increasing the system pressure within the continuous gas line by using the energy released during the methanation process.
Prestel discloses a system (i.e., a chemical synthesis plant; see FIG. 1, translation) for the production of a synthesis product from starting materials in a synthesis process, comprising:
a synthesis reactor 14 for the synthesis process (i.e., a reactor for performing a chemical reaction which catalytically converts starting materials at the appropriate temperature and pressure to a desired synthesis product; see translation at page 5, fourth paragraph), wherein the reactor 14 comprises an entry for the introduction of the starting materials (i.e., an inlet for receiving starting materials/educts) and an exit for the synthesis product (i.e., an outlet for discharging a mixture containing the synthesis product and unreacted starting materials);
a continuous gas line having an entrance (i.e., a line entrance upstream of a compressor 12) for the introduction of the feed gas and an exit (i.e., a line exit downstream of an expansion machine 16) for the removal of the product gas from the system; and
specifically, at least one turbocharger (i.e., a turbomachine; see translation at page 2, last paragraph; page 3, fifth paragraph; ref. claim 4) comprising a compressor 12 and a turbine (i.e., an expansion machine 16) mechanically connected by a common shaft (i.e., the compressor 12 and the expansion machine 16 are directly coupled to one another through a coupling unit 24, such as a shaft; see translation at page 2, sixth paragraph);
wherein the compressor 12 of the at least one turbocharger is connected with the continuous gas line and is arranged in a section of the continuous gas line which defines a path from the introduction of the starting material to the removal of the product gas, upstream of the synthesis reactor 14; and
wherein the compressor 12 of the at least one turbocharger is located in the continuous gas line at a position between the entrance of the continuous gas line and the entry of the synthesis reactor 14 such that the compressor 12 is capable of increasing the system pressure within the continuous gas line to a predetermined pressure higher pressure using the energy released during the chemical synthesis process (i.e., the energy released during the expansion of the reaction mixture through the expansion machine 16 is transmitted directly to the compressor 12 via the coupling unit 24, so that the energy can be reclaimed and used by the compressor 12 for compressing the starting materials; the energy released can include the energy of an exothermic reaction in the synthesis reactor 14, as well as heat energy added by a preheating stage 18 or additional heating stage(s), not shown; see translation at page 3, second paragraph; page 4, third paragraph; page 5, last two paragraphs).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to substitute at least one turbocharger comprising a compressor and a turbine mechanically connected by a common shaft for at least one compressor and controllable throttling device in the system of Zuberbuehler et al. because the energy released during the gas expansion through the turbine can be partially or wholly recovered and transmitted directly to the compressor via the common shaft, so that the energy can be used by the compressor for performing gas compression and, accordingly, a lot of energy can be saved and a reduced amount of energy would be needed from outside energy sources, as taught by Prestel. By comparison, the energy released during gas expansion through a controllable throttling device is lost to the surroundings and no longer available for further use by the system. (see translation at page 1, last paragraph, to page 2, fourth paragraph; page 3, second to last paragraph; page 4, third and fourth paragraphs; page 5, fifth and sixth paragraphs).
Zuberbuehler et al. further discloses that the pressure of the feed gas entering the reactor R1 can be set to 1 bar or more and 16 bar or less (see translation at page 4, last paragraph). For instance, the reactor R1 can be operated at a very low pressure, e.g., in the range from 1.5 to 2 bar, but greater than ambient pressure by a predetermined safety margin (see translation at page 12, second to last paragraph). Therefore, the pressure at the entrance of the continuous gas line (i.e., upstream of compressor 7.1) is essentially ambient pressure.
Zuberbuehler et al. further discloses that the final product gas leaving the system (i.e., downstream of the controllable throttling device 9.2; or downstream of the controllable throttling device 9.3) has a pressure suitable for further processing, such as for feeding into an existing natural gas network as a “synthetic” natural gas (see translation at page 3, seventh paragraph; page 10, fifth paragraph). As well-known in the art and further evidenced by Pipeline Safety Trust (see under “How Natural Gas Pipelines Work”), a natural gas network transmits natural gas under elevated pressure. Thus, it would have been obvious to one of ordinary skill in the art that the final product gas should be removed from the system (i.e., at point A, A3) at an elevated pressure, in order to facilitate the feeding of the final product gas into the transmission lines of the natural gas network.
Therefore, it would have been further obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to configure the compressor of the at least one turbocharger in the modified system of Zuberbuehler et al. to be capable of increasing the system pressure within the continuous gas line to achieve “a higher pressure at the exit of the continuous gas line than at the entrance of the continuous gas line” because the pressure at the entrance of the continuous gas line would be ambient pressure, and the provision of a higher pressure at the exit of the continuous gas line would have facilitated the feeding of the final product gas, as a synthetic natural gas, into the transmission lines of an existing natural gas network, which transmits natural gas under elevated pressure, as further evidenced by Pipeline Safety Trust.
Regarding claim 13, Zuberbuehler et al. (see FIG. 1) discloses that the system comprises a water/steam injection device (i.e., a H2O feed device 5.1, 5.2, 5.3; see paragraph [0077], [0079]) for injecting water/steam into the at least one methanation reactor R1, R2, R3. As shown, the water/steam injection device 5.1, 5.2, 5.3 injects the water/steam into the gas stream in the continuous gas line immediately upstream the entrance of the reactor R1, R2, R3.
Zuberbuehler et al. does not show that the water/steam injection device 5.1, 5.2, 5.3 directly injects the water/steam into the at least one methanation reactor R1, R2, R3 or into the continuous gas line upstream of the entry E for the introduction of feed gas.
However, it would have been an obvious design consideration for one of ordinary skill in the art before the effective filing date of the claimed invention to position the water/steam injection device to directly inject the water/steam into the at least one methanation reactor or into the continuous gas line upstream of the entry for the introduction of feed gas in the modified system of Zuberbuehler et al. because any of the water/steam injection locations would have achieved substantially the same result of adjusting the water content of the gases being processed in the continuous gas line, and a rearrangement of parts, without modifying the operation of the apparatus, was held to be obvious. See MPEP § 2144.04, VI, C.
Regarding claim 15, Zuberbuehler et al. (see FIG. 1) discloses that the controllable throttling devices 9.1, 9.2, 9.3 are connected to the continuous gas line.
Prestel (see FIG. 1) also discloses that the turbine 16 of the at least one turbocharger is connected to the continuous gas line (i.e., downstream of the synthesis reactor 14).
Therefore, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to connect the turbine of the at least one turbocharger to the continuous gas line in the modified system of Zuberbuehler et al. because the connection of the turbine of the turbocharger to the continuous gas line, at the same locations previously occupied by the controllable throttling devices, would have allowed for the turbine of the turbocharger to perform the same function of expanding the gases at the required locations in the continuous gas line.
Allowable Subject Matter
Claims 14 and 20 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JENNIFER A LEUNG whose telephone number is (571)272-1449. The examiner can normally be reached Monday - Friday 9:30 AM - 4:30 PM EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, CLAIRE X WANG can be reached at (571)270-1051. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JENNIFER A LEUNG/Primary Examiner, Art Unit 1774
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