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 .
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.
Claim 4 is 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.
Claim 4 recites, “wherein the water recovery subsystem comprises a water-cooled condenser, a steam re-evaporator, and a pump configured to allow the system to operate in a water-neutral state.” However, it is unclear whether the instantly claimed steam re-evaporator is the same or different steam evaporator recited in claim 1. A review of the instant specification discloses that the liquid-cooled condenser and an exhaust-heated re-evaporator produce steam, which can in turn be used to humidify the incoming fuel… [PgPublication – par. 0060]. Moreover, the instant application fails to disclose that the steam generated by the evaporator may be condense to liquid water that may be re-evaporated into steam prior to form a mixed gas to be mixed in the mixing device with the fuel mixture. Thus, for examination purposes, the “re-evaporator” recited in the instant claim is interpreted to be the same as that recited in claim 1. It is recommended that the recitation “a steam re-evaporator” be amended to recite --the steam evaporator-- for clarification purposes.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 17 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Varatharajan (US20050079395A1).
Regarding Claim 17, Varatharajan discloses a method for producing electrical power (power plant 10) [pars. 0013-15,0017-21; Fig. 3], comprising:
desulfurizing a fresh fuel stream comprising at least one of a hydrocarbon and hydrogen gas [par. 0019];
mixing the fresh fuel stream with a mixing gas (e.g., hot anode exhaust) to form a fuel mixture (e.g., point where de-sulferized fuel 56 is mixed with re-circulated hot exhausted fuel via re-circulation flow path 82) [par. 0040];
providing the fuel mixture to a protonic ceramic fuel cell stack to produce electrical power, an anode exhaust gas, and a cathode exhaust gas [par. 0031];
combining the anode exhaust gas 60 and the cathode exhaust gas 64 in a catalytic combustor (tail gas burner 38) to oxidize residual fuel components in the anode exhaust gas [par. 0020]; and
recovering thermal energy from at least one of the anode exhaust gas and the cathode exhaust gas and using the recovered thermal energy to preheat the fuel mixture (i.e., by recirculation of hot anode exhaust gas 60 to the fresh fuel stream 56) [par. 0040]
wherein the mixing gas comprises at least one of steam and a recycled portion of the anode exhaust gas.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
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.
Claim(s) 18-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Varatharajan (US20050079395A1), as applied to claim 1 above, and further in view of Bloomfield (US5976724A).
Regarding Claims 18-20, Varatharajan inherently discloses wherein the anode exhaust gas comprises water, and wherein the cathode exhaust gas comprises water, but fails to disclose the method further comprising: (i) recovering at least a portion of the water from the anode exhaust gas and recycling the recovered water for fuel reforming; (ii) recovering recovering at least a portion of the water from the cathode exhaust gas and recycling the recovered water for fuel reforming, wherein the method is water-neutral. However, Bloomfield, from the same field of endeavor, discloses method for producing electrical power from a fuel cell system (fuel cell power plant) comprising a fuel cell 100 and a water recovery subsystem, configured to recover water from at least one of the anode exhaust gas and the cathode exhaust gas and recycle the recovered water for fuel reforming in order to provide heat to the reformer in the form of steam (i.e., water recovered from burner exhaust by condenser 280 which includes anode exhaust that has passed the burner and water from cathode section 130 is sent to boiler 160 to produce steam which is them mixed with air and sent to the reformer), wherein the method is water-neutral (i.e., only the water recovered from the anode exhaust gas and cathode exhaust gas is separated and used) [Bloomfield – C38-C45; Fig. 2]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have modified the method of Varatharajan to have further comprised: (i) recovering at least a portion of the water from the anode exhaust gas and recycling the recovered water for fuel reforming; (ii) recovering recovering at least a portion of the water from the cathode exhaust gas and recycling the recovered water for fuel reforming, in order to provide heat to the reformer in the form of steam, wherein the method is water-neutral.
Claim(s) 1-2, 4-5, 7-13 and 15-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Varatharajan (US20050079395A1), Zhu (“Thermodynamic Analysis of Energy Efficiency and Fuel Utilization in Protonic-Ceramic Fuel Cells with Planar Co-Flow Configurations” – see IDS), Weingaertner (US20110053027A1) and Bloomfield (US5976724A).
Regarding Claim 1, Varatharajan discloses a protonic ceramic fuel cell (PCFC) power generation system (power plant 10) [pars. 0013-15,0017-21; Fig. 3], comprising:
a packed bed desulfurizer 32, comprising an adsorbent and configured to desulfurize a fresh fuel stream comprising at least one of hydrogen gas and a hydrocarbon [par. 0019];
a mixing junction configured to mix the fresh fuel stream with a mixing gas (hot exhausted fuel) to form a fuel mixture (e.g., point where de-sulferized fuel 56 is mixed with re-circulated hot exhausted fuel via re-circulation flow path 82) [par. 0040];
a PCFC stack (fuel cell assembly 34 comprising a protonic ceramic fuel cell [par. 0015]), configured to receive the fuel mixture, containing repeat elements comprising:
an electrolyte configured to act as a proton conductor;
a cathode; and
an anode configured to catalyze in situ reforming of at least one hydrocarbon to hydrogen gas (i.e., reformer integral with fuel cell assembly 34 alternative to external reformer 36 – not shown) [par. 0018];
a combustor (tail gas burner 38), configured to receive an anode exhaust gas 60 and a cathode exhaust gas 64 from the PCFC stack and combine the anode exhaust gas and the cathode exhaust gas to oxidize residual fuel constituents in the anode exhaust gas [par. 0020]; and
a heat recuperation train, comprising a fuel preheater (i.e., fuel is heated by turbine exhaust 42,43,112 which by transfer to fuel passing through the desulfurizer), an air preheater (recuperator 20), configured to recover thermal energy from at least one of the anode exhaust gas and the cathode exhaust gas [pars. 0014,0019].
Varatharajan fails to explicitly disclose: (i) the PCFC stack is configured to operate at a nominal cell temperature of between about 500° C. and about 700° C.; (ii) the electrolyte is a doped perovskite-based electrolyte, having an ABO3−δ structure; (iii) the anode comprising particularly an impregnated catalyst configured to catalyze in situ reforming of the at least one hydrocarbon to hydrogen gas; (iv) the combustor is a catalytic combustor; (v) a mixing device, configured to mix the fresh fuel stream with a mixing gas to form the fuel mixture; (vi) the heat recuperation train further comprises a steam evaporator and is further configured to recover thermal energy from at least one of the anode exhaust gas and the cathode exhaust gas and use the recovered thermal energy to preheat the fuel mixture in the mixing device; (vii) a water recovery subsystem, configured to recover water from at least one of the anode exhaust gas and the cathode exhaust gas and recycle the recovered water for fuel reforming.
Pertaining (i)-(iii), Zhu, from the same field of endeavor, discloses that PCFC are mainly based on doped-perovskite electrolyte membranes (e.g., BaZr0.9Y0.1O3−δ electrolyte membrane) that are mixed ionic-electronic conductors (MIEC) that simultaneously transport protons, oxide ions and small polarons effectively at open-circuit, and further discloses operating the PCFC at 500–700◦C yielding high efficiency and fuel utilization [Zhu – pp. F942-F943,F946; Fig. 2]. Zhu further discloses the anode of the PCFC may comprise Ni-BZY which contribute to anti-coking resistance [pg. F948]. 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 Varatharajan, wherein: (i) the PCFC stack is configured to operate at a nominal cell temperature of between about 500° C. and about 700° C. demonstrating high efficiency and fuel utilization; (ii) the electrolyte is a doped perovskite-based electrolyte, having an ABO3−δ structure (e.g., BaZr0.9Y0.1O3−δ electrolyte membrane) that are mixed ionic-electronic conductors (MIEC) that simultaneously transport protons, oxide ions and small polarons effectively at open-circuit; and (iii) the anode comprising particularly an impregnated catalyst configured to catalyze in situ reforming of the at least one hydrocarbon to hydrogen gas which may contribute to anti-coking resistance.
Pertaining (iv), Weingaertner, from the same field of endeavor, teaches a fuel cell system comprising a catalytic combustor (anode tail gas oxidizer 10) configured to receive an anode exhaust gas and cathode exhaust gas from the fuel cell stack and combine the anode exhaust gas and cathode exhaust gas to oxidize residual fuel constituents in the anode exhaust gas [Weingaertner – pars. 0027,0031]. 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 Varatharajan, wherein the combustor is a catalytic combustor as a well-known combustor in the art for oxidizing anode exhaust gas and cathode exhaust gas from the fuel cell stack and combine the anode exhaust gas and cathode exhaust gas to oxidize residual fuel constituents in the anode exhaust gas.
Pertaining (v), Weingaertner teaches a mixing device (mixer 105), configured to mix fresh fuel stream with a mixing gas to form a fuel mixture. 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 Varatharajan to have further comprised a mixing device as a standard practice in the art for mixing fresh fuel stream with a mixing gas to form the fuel mixture.
Pertaining (vi), Weingaertner teaches the fuel cell system further comprises a steam evaporator (steam generator 103) configured to recover thermal energy from at least one of the anode exhaust gas and the cathode exhaust gas and use the recovered thermal energy from to preheat the fuel mixture in order to humidify the fuel mixture in the mixing device. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have modified the heat recuperation train of Varatharajan to have further comprised a steam evaporator and is further configured to recover thermal energy from at least one of the anode exhaust gas and the cathode exhaust gas and use the recovered thermal energy to preheat and humidify the fuel mixture in the mixing device.
Pertaining (vii), Bloomfield, from the same field of endeavor, discloses a fuel cell system (fuel cell power plant) comprising a fuel cell 100 and a water recovery subsystem, configured to recover water from at least one of the anode exhaust gas and the cathode exhaust gas and recycle the recovered water for fuel reforming in order to provide heat to the reformer in the form of steam (i.e., water recovered from burner exhaust by condenser 280 which includes anode exhaust that has passed the burner and water from cathode section 130 is sent to boiler 160 to produce steam which is them mixed with air and sent to the reformer) [Bloomfield – C38-C45; Fig. 2]. 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 Varatharajan to have further comprised a water recovery subsystem, configured to recover water from at least one of the anode exhaust gas and the cathode exhaust gas and recycle the recovered water for fuel reforming in order to provide heat to the reformer in the form of steam.
Regarding Claim 2, Varatharajan fails to disclose wherein the heat recuperation train is configured to preheat the fuel mixture to at least about 430° C. However, Zhu teaches that cell potential maximum efficiency is a function of temperature and fraction of fuel stream composition [F946-F947]. 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 Varatharajan to have controlled the temperature of the fuel mixture to be preheated to at least about 430o C in order to achieve maximum efficiency, without undue experimentation and with a reasonable expectation of success [MPEP 2144.05(II)].
Regarding Claim 4, modified Varatharajan discloses wherein the water recovery subsystem comprises a water-cooled condenser 280, a steam evaporator (boiler 160), and a pump 270 configured to allow the system to operate in a water-neutral state [Bloomfield – Fig. 2].
Regarding Claim 5, modified Varatharajan discloses further comprising a process heat recovery subsystem configured to receive rejected heat from at least one of the packed bed desulfurizer, the mixing device, the PCFC stack, the catalytic combustor, the heat recuperation train, and the water recovery subsystem and use the rejected heat to heat a water stream and thereby form a process heat stream, and further configured to exchange heat from the process heat stream to at least one of the packed bed desulfurizer, the mixing device, the PCFC stack, the catalytic combustor, the heat recuperation train, and the water recovery subsystem (e.g., Varatharajan discloses using rejected heat from the heat recuperation train to further heat the packed bed desulfurizer) [par. 0019; Fig. 3].
Regarding Claim 7, Varatharajan discloses the system further comprising an anode gas recycling (AGR) subsystem having at least one of a recycle blower and a gas ejector 84 [par. 0040].
Regarding Claim 8, Varatharajan fails to disclose wherein a proportion of the anode exhaust gas that is recycled by the AGR subsystem is between about 50% and about 90%. However, Zhu discloses that cell potential maximum efficiency is a function of temperature and fraction of fuel stream composition [F946-F948]. 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 Varatharajan to have controlled the proportion of the anode exhaust gas that is recycled by the AGR subsystem to be between 50% and about 90% in order to achieve maximum efficiency, without undue experimentation and with a reasonable expectation of success [MPEP 2144.05(II)].
Regarding Claim 9, Varatharajan discloses the system further comprising a catalytic hydrocarbon steam pre-reformer [Varatharajan – Claim 14; Weingaertner – par. 0026], wherein the catalytic hydrocarbon steam pre-reformer is upstream of the PCFC stack and configured to do at least one of the following:
(i) reduce at least a portion of C2+ hydrocarbons in the fuel mixture to methane before the fuel mixture enters the PCFC stack; and
(ii) reform at least a portion of hydrocarbons in the fuel mixture to hydrogen gas before the fuel mixture enters the PCFC stack.
Regarding Claim 10, Varatharajan discloses wherein the fresh fuel stream comprises natural gas [par. 0019].
Regarding Claim 11, Varatharajan discloses wherein the fresh fuel stream comprises at least one of a liquid hydrocarbon fuel, a biogas, a hydrogen gas, and an alcohol [par. 0019].
Regarding Claim 12, Varatharajan fails to disclose the system having an electrical efficiency of at least about 55% LHV. However, Zhu teaches that the electrical efficiency can be controlled by controlling operating voltages [Zhu – F949; Fig. 9C]. 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 Varatharajan to have controlled the operating voltage of the fuel cell stack in order to provide optimum electrical efficiency to be at least about 55% LHV, without undue experimentation and with a reasonable expectation of success [MPEP 2144.05(II)].
Regarding Claim 13, Zhu teaches that maximum fuel utilization can be achieved based on fuel composition and particularly when CH4 fraction of fuel is less than approximately 1/3 [Zhu – F949; Fig. 9d]. 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 Varatharajan to have controlled the CH4 amount in the fuel stream in order to achieve optimum fuel utilization of between 75% to about 95%, without undue experimentation and with a reasonable expectation of success [MPEP 2144.05(II)].
Regarding Claim 15, Varatharajan discloses the system further comprising a cathode gas recycling (CGR) subsystem, wherein the CGR subsystem comprises at least one of a recycle blower and a cathode gas ejector [par. 0035; Fig. 3].
Regarding Claim 16, Varatharajan fails to disclose wherein a proportion of the cathode exhaust gas that is recycled by the CGR subsystem is between about 25% and about 75%. However, Varatharajan teaches proportion of the cathode exhaust gas that is recycled facilitates a substantially constant total system air flow rate for increased system performance [par. 0037]. 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 Varatharajan to have controlled the proportion of the cathode exhaust gas that is recycled by the CGR subsystem to be between 25% and about 75% in order to facilitate a substantially constant total system air flow rate for increased system performance, without undue experimentation and with a reasonable expectation of success [MPEP 2144.05(II)].
Claim(s) 3 is/are rejected under 35 U.S.C. 103 as being unpatentable over Varatharajan, Zhu, Weingaertner and Bloomfield, as applied to claim 1 above, and further in view of Hatada (US20110039174A1).
Regarding Claim 3, Varatharajan fails to discloses wherein a steam-to-carbon (S/C) molar ratio in the fuel mixture is between about 2.0 and about 3.0. However, Hatada, from the same field of endeavor, teaches for ceramic based fuel cells, such as SOFC, with internal reforming process, in order to suppress carbon deposition resulting in anode degradation and flow blockage, the flow rate of water supplied to reformer may be set so that the steam/carbon ratio is a predetermined value such as between 2 to 5 [Hatada – pars. 0008,0177,0300]. 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 Varatharajan to have optimized the steam-to-carbon molar ratio in the fuel mixture to be between 2.0 and about 3.0 in order to suppress carbon deposition resulting in anode degradation and flow blockage, without undue experimentation and with a reasonable expectation of success [MPEP 2144.05(II)].
Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Varatharajan, Zhu, Weingaertner and Bloomfield, as applied to claim 1 above, and further in view of Chen (“An In Situ Formed, Dual-Phase Cathode with a Highly Active Catalyst Coating for Protonic Ceramic Fuel Cells”).
Regarding Claim 6, Varatharajan discloses wherein the anode and the cathode are part of a membrane electrode assembly but fails to disclose the assembly further comprises at least one electrode functional layer. However, Chen, from the same field of endeavor, teaches an electrode functional layer (perovskite PrNi0.5Mn0.5O3 (PNM) surface coating) on a cathode of a protonic ceramic fuel cell, the hybrid cathode displayed excellent electrocatalytic activity and remarkable long-term stability [Chen – Abstract]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have modified the assembly of Varatharajan to have comprised perovskite PrNi0.5Mn0.5O3 (PNM) surface coating as an electrode functional layer in order to provide excellent electrocatalytic activity and remarkable long-term stability.
Claim(s) 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Varatharajan, Zhu, Weingaertner and Bloomfield, as applied to claim 1 above, and further in view of Ding (“Self-sustainable protonic ceramic electrochemical cells using a triple conducting electrode for hydrogen and power production”).
Regarding Claim 14, Varatharajan fails to discloses wherein the cathode is a triple-conducting cathode. However, Ding, from the same field of endeavor, teaches use of a triple conducting oxide as a cathode presenting superior electrochemical performance at 400-600oC [Ding – Abstract]. Therefore, before the effective filing date of the claimed invention, it would have been obvious for an ordinary skilled artisan to have modified the assembly of Varatharajan wherein the cathode is a triple-conducting cathode in order to achieve superior electrochemical performance at 400-600oC.
Conclusion
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