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
This is a final office action in response to Applicant's remarks and amendments filed on 5/21/2026. Claim 1 is currently amended. Claims 1-17 are pending review in this action.
The 35 U.S.C. 112 rejections in the previous Office Action are withdrawn.
New grounds of rejection necessitated by Applicant's amendments are presented below.
Response to Arguments
Applicant’s arguments with respect to amended claim 1 have been considered but are moot in view of the new grounds of rejection.
The Examiner agrees that the primary reference, Agnew, does not disclose a heat exchanger configured to recover heat form the flue gas to preheat the oxidant prior to entering the SOFC unit, and instead teaches ejecting the exhaust and preheating the oxidant via the combustor products. However, the newly added limitation is a well-known thermal management technique explicitly taught by a previously cited reference, Gottmann, which discloses recovering heat from the flue gas of a combustor unit to preheat the oxidant prior to entering the fuel cell.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1-6, 9-11 and 12-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Agnew (US 2004/0062973 A1) in view of Viteri (US 2002/0174659 A1 – see IDS) and Gottmann (US 2003/0157386 A1).
Regarding Claim 1, Agnew discloses an energy conversion system (fuel cell systems 210) [par. 0045; Fig. 3] comprising:
a Solid Oxide Fuel Cell (SOFC) unit 12 having an anode 20 and a cathode 22 side, configured for receiving a fuel 28 and a stream of oxidant 32 and for converting a fraction of chemical power of the fuel directly into electric power through one or more electrochemical reactions occurring on the anode and the cathode side of the SOFC unit involving said fuel and said oxidant, parts of the fuel and of the stream of oxidant being maintained unconverted following said electrochemical reactions (i.e., unused fuel and oxidant from collection manifolds 36,48 respectively) [pars. 0030-35];
a combustor unit 46 arranged to receive the unconverted fuel and the unconverted oxidant from the SOFC unit, configured for the combustion of the unconverted fuel using the unconverted oxidant, thereby converting the unconverted fuel and the unconverted oxidant into product gas (i.e., hot gases) [pars. 0034-36];
an expander unit (i.e., turbine 62) arranged to receive the product gas (i.e., via duct 72) exiting the combustor and configured for expanding said product gas exiting the combustor into flue gas (exhaust 68) [pars. 0046,0037]; and
a first compression unit (compressor 60 and/or ejector 58) connected to an input of the SOFC unit and configured to increase the pressure of said oxidant to a value suitable for the SOFC unit and the combustor unit [pars. 0031,0036,0047,0058].
Agnew fails to disclose: (i) a cooler unit in thermal relationship with a heat sink and configured for cooling said flue gas exiting the expander unit; (ii) a separator for removing condensed species from the cooled gas exiting the cooler unit, thereby obtaining a recycled stream; and (iii) a heat exchanger disposed between said first compression unit and said SOFC unit and configured to recover heat from said flue gas to preheat the oxidant prior to entering sad SOFC unit.
Pertaining (i) and (ii) above, Viteri, from the same field of endeavor, discloses an energy conversion system with a similar configuration to that of Agnew, comprising a SOFC 50, a combustor 60 configured to receive unconverted fuel and oxidant of the SOFC to produce a product gas which is further sent to an expander unit (turbine 70) configured for expanding said product gas into flue gas, the flue gas is then sent to a cooler unit (heat recovery sybsystem 90) in thermal relationship with a heat sink (i.e., water from subsystem 130), and a separator 110/120 in order to condense the water in flue gas into cooled steam and liquid water, and further, to separate gaseous CO2, wherein the cooled steam and CO2 can be recycled to the compression unit or to the combustor unit, excess liquid water can be used as makeup water for other subsystems, and CO2 can be processed for sale as a byproduct, or prepared for sequestration into underground formations or deep ocean disposal sites [Viteri – pars. 0112-116; Fig. 1]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have employed the teachings of Viteri to have modified the system of Agnew to have further comprised (i) a cooler unit in thermal relationship with a heat sink and configured for cooling said flue gas exiting the expander unit; and (ii) a separator for removing condensed species from the cooled gas exiting the cooler unit, thereby obtaining a recycled stream in order to condense the water in flue gas into cooled steam and liquid water, and further, to separate gaseous CO2, wherein the cooled steam and CO2 can be recycled to the compression unit or to the combustor unit, excess liquid water can be used as makeup water for other subsystems, and CO2 can be processed for sale as a byproduct, or prepared for sequestration into underground formations or deep ocean disposal sites.
Pertaining (iii) above, Gottman, from the same field of endeavor, discloses an energy conversion system comprising an SOFC 68, an oxidizer compressor 84 (i.e., first compression unit) connected to an input of the SOFC and configured to increase the pressure of said oxidizer (i.e., oxidant), and a gas turbine 90, wherein an oxidizer preheater 24 and a turbine exhaust heat exchanger 98 are combined as a single heat exchanger 24/98 disposed between the compressor and the SOFC unit, and configured to recover heat from the burner 30 exhaust (i.e., flue gas) to preheat the oxidizer (i.e., oxidant) prior to entering the fuel cell [Gottman – par. 0119; Fig. 10C]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have employed the teachings of Gottmann to have further modified the energy conversion system of Agnew to have comprised a heat exchanger disposed between said first compression unit and said SOFC unit and configured to recover heat from said flue gas to preheat the oxidant prior to entering sad SOFC unitin order to improve the overall thermal efficiency of the hybrid SOFC-gas turbine system by harnessing waste heat from the flue gas of the combustor unit to preheat incoming reactants.
Regarding Claim 2, modified Agnew discloses wherein the SOFC unit is configured to work with an oxidant stream composed of a mixture of CO2 and oxygen {Examiner notes that this is an implicit feature of a SOFC system wherein the portion of the combustor product containing CO2 is recycled to the cathode side, and thus, the SOFC unit of Agnew is necessarily configured to work with an oxidant stream}.
Regarding Claim 3, Agnew discloses wherein the SOFC unit is configured to work at pressures comprised int eh range between 5 and 500 bar (e.g., 7 bar since another pump 58A may be installed an intake of the SOFC unit as shown in Fig. 4 [pars. 0052-57, or alternatively, Agnew discloses that the compressor may be a high pressure compressor [par. 0058] such that the pressure of the oxidant may be higher than 7 bar, especially with combination of high pressure compressor, additional pump, and ejector).
Regarding Claim 4, Agnew fails to disclose wherein the SOFC unit is configured to work at pressures comprised in the range between 250 and 360 bar. However, the claimed configuration is an operational parameter which is a technical feature of a SOFC stack capable of being controlled for obtain desired characteristic of streams entering or exiting the fuel cell stack. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have modified the system of Agnew wherein the SOFC unit is configured to work at pressures comprised in the range between 250 and 360 bar in order to obtain desired characteristics of streams entering or exiting the fuel cell stack without undue experimentation and with a reasonable expectation of success [MPEP 2144.05(II)].
Regarding Claim 5, Agnew discloses wherein the SOFC unit is configured to work at temperatures comprised in the range between 650 and 850° C [par. 0055].
Regarding Claim 6, Agnew discloses wherein the expander unit (C) is configured such that the flue gas outlet pressure is between 1 and 50 bar (e.g., 1.013 bar) [par. 0055].
Regarding Claim 9, Agnew discloses wherein the SOFC unit is configured to run with an internal reforming process (i.e., via reformer 74) [par. 0053,0056; Fig. 4].
Regarding Claim 10, Agnew discloses the fuel supply may be a hydrocarbon fuel such as methane [par. 0053], wherein fails to explicitly disclose wherein the SOFC unit is configured to run with a pre-reforming process. However, providing a SOFC system with a pre-reformer for reforming hydrocarbon to hydrogen fuel is a well-known configuration in the art as taught by Viteri [Fig. 1]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have further modified the system of Agnew wherein the SOFC unit is configured to run with a pre-reforming process in order to convert hydrocarbon into a hydrogen, either in addition to an internal reformer or in lieu of the internal reformer.
Regarding Claim 11, Agnew fails to explicitly disclose wherein the combustor unit is a catalytic combustion unit. However, Gottmann discloses the similar energy conversion system to that of Agnew in which unconverted fuel and oxidant are fed to a combustor unit (burner), wherein the combustor unit is a catalytic combustion unit (i.e., the chemical reaction of the unconverted fuel and oxidant in the burner can be initiated by an optional catalyst material) [Gottmann – par. 0091]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have further modified the system of Agnew wherein the combustor unit is a catalytic combustion unit in order to initiate the chemical reaction between the unconverted fuel and oxidant.
Regarding Claim 12, modified Agnew discloses the system further comprising a heat exchanger unit (D) for preheating at least one of the streams entering the SOFC and/or the combustor, wherein said heat exchanger unit (D) is in thermal relationship with the expander exhaust gas and/or with other hot streams of the energy conversion system itself and/or with one or more further plants (i.e., as part of subsystem 90) [Viteri – pars. 0014-16; Fig. 1].
Regarding Claim 13, Agnew discloses the system further comprising one or more heater and/or one or more cooler (heat exchanger 74) for modifying the temperatures of the streams entering and/or exiting the SOFC to desired values [par. 0047; Fig. 3].
Regarding Claim 14, Viteri discloses the recycled stream is sent to a second compressor unit 40 to obtain a compressed recycle stream to be mixed with incoming oxidant at a suitable pressure of the first compressor unit 10 [Viteri – par. 0016; Fig. 1]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have modified the system of Agnew to have further comprised a second compressor unit for compressing said recycled stream, thereby obtaining a compressed recycled stream, prior to mixing with the incoming oxidant at a suitable pressure of the first compression unit.
Regarding Claim 15, modified Agnew fails to disclose the energy conversion system further comprises a third compressor unit for compressing at least a portion of said compressed recycled stream to a pressure suitable for the combustor. However, for similar reason specified above, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have further modified the system of Agnew to have further comprised a third compressor unit for compressing at least a portion of said compressed recycled stream to a pressure suitable for the combustor.
Regarding Claim 16, modified Agnew discloses wherein the SOFC unit is configured for further receiving a stream of steam (i.e., from separator 120) [Viteri – Fig. 1].
Claim(s) 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Agnew and Viteri, as applied to claim 6, above, and further in view of Griffin (US 2002/0043064 A1 – see IDS).
Regarding Claim 7, Agnew fails to disclose wherein the expander unit is configured such that the flue gas outlet pressure is between 1 and 50 bar, or between 10 and 30 bar. However, Griffin, from the same field of endeavor, discloses a similar energy conversion system comprising a SOFC 81 from which unconverted fuel and oxidant are fed to a combustor (burner 45) which in turn feeds the product gas 13 to an expander unit (turbine 5), wherein the expander unit is configured such that the flue gas 8 from the expander unit is configured to have an outlet pressure of 10 bar [pars. 0019-20Fig. 2]. Therefore, before the effective filing date of the claimed configuration, it would have been obvious for an ordinary skilled artisan to have further modified the system of Agnew wherein the expander unit is configured such that the flue gas outlet pressure is 10 bar, as a well-known turbine flue gas outlet pressure for a similar energy conversion system.
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Agnew and Viteri, as applied to claim 1, above, and further in view of Ozawa (US 2014/0190144 A1).
Regarding Claim 8, Agnew fails to disclose wherein the combustor unit is configured for combusting additional fuel and/or an additional oxidant in addition to said unconverted fuel and to said unconverted oxidant exiting from the SOFC unit. However, it is well-known in the art to supply additional or a supplement source of fuel and/or oxidant to a combustor which is configured to combust the unconverted fuel/oxidant of a fuel cell. For example, Ozawa, from the same field of endeavor, discloses an energy conversion system in which unconverted fuel (through line 45) and oxidant (through line 36) of a SOFC 13 are configured to be fed to a combustor 22 [Fig. 1]. Ozawa further discloses wherein the combustor unit is configured for combusting additional fuel (through line 27) and/or an additional oxidant (through line 26) in addition to said unconverted fuel and to said unconverted oxidant exiting from the SOFC unit [pars. 0039,0041; Fig. 1]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have further modified the system of Agnew wherein the combustor unit is configured for combusting additional fuel and/or an additional oxidant in addition to said unconverted fuel and to said unconverted oxidant exiting from the SOFC unit as a known configuration in the art for supplying supplemental sources of fuel and oxidant to the combustor.
Claim(s) 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Agnew and Viteri, as applied to claim 1, above, and further in view of Grieve (US 2005/0196659 A1).
Regarding Claim 17, Agnew fails to disclose the system further comprising at least a second SOFC unit and/or at least a second combustor unit after the expander unit. However, it is well-known to utilize multiple fuel cell units and combustor units in fuel cell systems. For example, Grieve discloses a first SOFC 16, the unused fuel and oxidants of which are routed to a first combustor 136, and a second SOFC 10, the unused fuel and oxidants of which are routed to a first combustor 154 to form a hybrid auxiliary power system [Grieve – Fig. 3]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have further modified the system of Agnew to have comprised at least a second SOFC unit and/or at least a second combustor unit after the expander unit to form a hybrid auxiliary power system.
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 HAROON S SHEIKH whose telephone number is (571)270-0302. The examiner can normally be reached 9-6.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, JONATHAN LEONG can be reached at (571) 270-1292. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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HAROON S. SHEIKH
Primary Examiner
Art Unit 1751
/Haroon S. Sheikh/Primary Examiner, Art Unit 1751
