CA2247466A1 - Self-cooling mono-container fuel cell generators and power plants using an array of such generators - Google Patents
Self-cooling mono-container fuel cell generators and power plants using an array of such generators Download PDFInfo
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- CA2247466A1 CA2247466A1 CA002247466A CA2247466A CA2247466A1 CA 2247466 A1 CA2247466 A1 CA 2247466A1 CA 002247466 A CA002247466 A CA 002247466A CA 2247466 A CA2247466 A CA 2247466A CA 2247466 A1 CA2247466 A1 CA 2247466A1
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- fuel
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- 239000000446 fuel Substances 0.000 title claims abstract description 196
- 238000001816 cooling Methods 0.000 title claims abstract description 65
- 238000009413 insulation Methods 0.000 claims abstract description 86
- 239000003792 electrolyte Substances 0.000 claims abstract description 20
- 239000000463 material Substances 0.000 claims abstract description 14
- 230000015556 catabolic process Effects 0.000 claims abstract description 6
- 238000006731 degradation reaction Methods 0.000 claims abstract description 6
- 239000007800 oxidant agent Substances 0.000 claims description 56
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- 229910052751 metal Inorganic materials 0.000 claims description 20
- 239000002184 metal Substances 0.000 claims description 20
- 239000001301 oxygen Substances 0.000 claims description 12
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- 239000004567 concrete Substances 0.000 claims description 10
- 239000002737 fuel gas Substances 0.000 claims description 10
- 239000000919 ceramic Substances 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 7
- 239000000112 cooling gas Substances 0.000 claims description 6
- 239000002905 metal composite material Substances 0.000 claims description 4
- 239000000110 cooling liquid Substances 0.000 claims description 3
- 239000003570 air Substances 0.000 description 38
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 12
- 239000007787 solid Substances 0.000 description 11
- 229910000831 Steel Inorganic materials 0.000 description 9
- 239000010959 steel Substances 0.000 description 9
- 239000003245 coal Substances 0.000 description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- 238000003491 array Methods 0.000 description 5
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- 239000000306 component Substances 0.000 description 5
- 239000003345 natural gas Substances 0.000 description 5
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 4
- 238000002309 gasification Methods 0.000 description 4
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- 238000010248 power generation Methods 0.000 description 3
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000012080 ambient air Substances 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 239000011195 cermet Substances 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 239000007772 electrode material Substances 0.000 description 2
- 239000002803 fossil fuel Substances 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002915 spent fuel radioactive waste Substances 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 102100026933 Myelin-associated neurite-outgrowth inhibitor Human genes 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 206010037660 Pyrexia Diseases 0.000 description 1
- 101150094640 Siae gene Proteins 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- MCMNRKCIXSYSNV-UHFFFAOYSA-N ZrO2 Inorganic materials O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 239000010405 anode material Substances 0.000 description 1
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- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
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- 239000010406 cathode material Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- NFYLSJDPENHSBT-UHFFFAOYSA-N chromium(3+);lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Cr+3].[La+3] NFYLSJDPENHSBT-UHFFFAOYSA-N 0.000 description 1
- 239000003034 coal gas Substances 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
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- 239000011210 fiber-reinforced concrete Substances 0.000 description 1
- 239000011152 fibreglass Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000009421 internal insulation Methods 0.000 description 1
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- 239000011244 liquid electrolyte Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052574 oxide ceramic Inorganic materials 0.000 description 1
- 239000011224 oxide ceramic Substances 0.000 description 1
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- 229910001233 yttria-stabilized zirconia Inorganic materials 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
- H01M8/04067—Heat exchange or temperature measuring elements, thermal insulation, e.g. heat pipes, heat pumps, fins
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
- H01M50/233—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions
- H01M50/24—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions adapted for protecting batteries from their environment, e.g. from corrosion
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
- H01M8/2465—Details of groupings of fuel cells
- H01M8/247—Arrangements for tightening a stack, for accommodation of a stack in a tank or for assembling different tanks
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
- H01M8/2465—Details of groupings of fuel cells
- H01M8/247—Arrangements for tightening a stack, for accommodation of a stack in a tank or for assembling different tanks
- H01M8/2475—Enclosures, casings or containers of fuel cell stacks
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/10—Fuel cells with solid electrolytes
- H01M8/12—Fuel cells with solid electrolytes operating at high temperature, e.g. with stabilised ZrO2 electrolyte
- H01M2008/1293—Fuel cells with solid oxide electrolytes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0065—Solid electrolytes
- H01M2300/0068—Solid electrolytes inorganic
- H01M2300/0071—Oxides
- H01M2300/0074—Ion conductive at high temperature
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
- H01M8/04014—Heat exchange using gaseous fluids; Heat exchange by combustion of reactants
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04007—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids related to heat exchange
- H01M8/04014—Heat exchange using gaseous fluids; Heat exchange by combustion of reactants
- H01M8/04022—Heating by combustion
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
- H01M8/04082—Arrangements for control of reactant parameters, e.g. pressure or concentration
- H01M8/04089—Arrangements for control of reactant parameters, e.g. pressure or concentration of gaseous reactants
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/24—Grouping of fuel cells, e.g. stacking of fuel cells
- H01M8/249—Grouping of fuel cells, e.g. stacking of fuel cells comprising two or more groupings of fuel cells, e.g. modular assemblies
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Fuel Cell (AREA)
Abstract
A mono-container fuel cell generator (10) contains a layer of interior insulation (14), a layer of exterior insulation (16) and a single housing (20) between the insulation layers, where fuel cells, containing electrodes and electrolyte, are surrounded by the interior insulation (14) in the interior (12) of the generator, and the generator is capable of operating at temperatures over about 650 ~C, where the combination of interior and exterior insulation layers have the ability to control the temperature in the housing (20) below the degradation temperature of the housing material. The housing can also contain integral cooling ducts, and a plurality of these generators can be positioned next to each other to provide a power block array with interior cooling.
Description
CA 02247466 l998-08-2l W O 98/29917 PCTrUS96/2~749 SELF-COOLING MONO-CONTAINER FUEL CELL GENERATORS
AND POWER PLANTS USING AN ARRAY OF SUCH GENERATORS
GOVERNMENT CONTRACT
The Government of the United States of America has rights in this invention, pursuant to Contract No. DE-FC21-slMC28055 with the United States Department of Energy.
FIELD OF TH~ INVENTION
The invention relates to heat controlled, solid oxide electrolyte, fuel cell generators, and to an array of such generators disposed in a mono-container shell, for use with a variety of auxiliary components in a power genera-tion system of the 100kW to 50MW plus capacity.
BACKGROUND AND SUMMARY OF THE INVENTION
Fuel cell based, electrical generator apparatus ("generators") utilizing solid oxide electrolyte fuel cells ("SOFC") disposed within a housing and surrounded by insulation are well known, and taught, for example, by U.S.
Patent Nos: 4,395,468 (Isenberg) and "Solid Oxide Fuel Cell", Westinghouse Electric Corporation, October 1992, for tubular SOFC; 4,476,196 (Poppel, et al.~ for flat plate SOFC; and 4,476,198 (Ackerman, et al.) for "corrugated"
SOFC, all herein incorporated by reference. The tubular type fuel cells can comprise an open or closed ended, axially elongated, ceramic tube air electrode material, which can be deposited on a ceramic support tube, com-pletely covered by thin film ceramic, solid electrolyte material. The electrolyte is substantially covered by cermet fuel electrode material, except for a thin, axially elongated, interconnection material. The flat plate type W O 98/29917 2 PCT~S96/20749 ~uel cells can comprise a flat array o~ electrolyte a-d interconnect walls, where electrolyte walls contain thin, flat layers of cathode and anode materials sandwiching an electrolyte. The "corrugated" plate type fuel cells can comprise a triangular or corrugated honeycomb array of active anode, cathode, electrolyte and interconnect mate-rials. Other fuel cells not having a solid electrolyte, such molten carbonate fuel cells are also well known, and can be insulated using the mono-container of this inven-tion.
In construction of ~uel cell generators, stable insulation was thought essential, and both interior and exterior steel housing shells, with the high temperature insulation between them, were thought important to protect lS the insulation from hydrogen gas or other fuel gas permea-tion, which could cause loss of insulating gases from the insulation pores, as taught in U.S. Patent No. 4,640,875 (Makiel). Appropriate seals for a two part intericr housing are also taught in that patent, allowing for radial and longitudinal expansion o~ the interior housing during thermal cycling and operation o~ the generator. Use of an inner metal canister to protect a certain portion of the insulation, and act as one wall o~ corner heating condui~s is taught in U.S. Patent No. 4,808,491 (Reichner). This aual metal housing design was the primary configuration r~-experimental 2SkW generators. In all cases, insulation was disposed on the inside of the exterior metal housing.
In previous designs, the oxidant air ~eed manifold system, which could be similar to that shown in U.S. Patent No. 4,664,986 (Draper et al.), and portions of the inner metal canister, were contacted with reacted, depleted oxidant/fuel hot exhaust gases in a combustion chamber, which resulted in high interior metal housing temperatures.
High metal housing temperatures can be handled for a single generator by using exotic steels and ceramic materials.
However, for commercial applications, where an array of multiple generators might be electrically connected to provide MW system output, active cooling would be required CA 02247466 l998-08-2l on sides of those generators not located on the periphery of the system. The high cost of specialty steels and ceramics ~or single generators remains a problem, and the ~ problem of cooling the interior of an array of solid oxide fuel cell generators poses serious difficulties not previ-ously addressed. Without such central cooling, buckling and potential failure of cont~inm~nt vessels near the center of the array could result after long operation.
A variety of fuel cell systems are described in the literature. In U.S. Patent No. 3,972,731 (Bloomfield et al.), a pressurized fuel cell power plant is described.
There, air is compressed by compressor apparatus, such as a compressor and turbine which are operably connected, which is powered by waste energy produced by the power plant in the form of a hot pressurized gaseous medium, such as fuel cell exhaust gases. These exhaust gases are delivered into the turbine, which drives the compressor for compressing air delivered to the fuel cells. In U.S.
Patent No. 5,413,879 (Domeracki et al.) a SOFC was also integrated into a gas turbine system. There, pre-heated, compressed air i8 supplied to a SOFC along with fuel, to produce electric power and a hot gas, which gas is further heated by combustion of unreacted fuel and oxygen remaining in the hot gas. This higher temperature gas is directed to a topping combustor that is supplied with a second stream of fuel, to produce a still further heated gas that is then expanded in a turbine.
U.S. Patent No. 4,622,275 (Noguchi et al.) alsc describes a fuel cell power plant, where reformed, reactive fuel is fed to an anode of the cell, an expansion turbine connected to a compressor feeds compressed gas into the cathode of the cell, which compressed gas is mixed with anode exhaust gas which had been combusted.
A~ pointed out previously, in power plant applica-tions, arrays of fuel cell generators, modules, or powerblocks will have to be cooled in the interior of the array to prevent overheating and possible failure o~ non-ceram _ components. Also, to be commercially competitive, ~he W O 98/29917 PCTAUS96/207~9 number of housing shells must be reduced. It is one of the objectives of this invention to provide a heat controlled generator and a cooled array of mono-container generators.
Accordingly, the invention resides ln a self-cooling, mono-container fuel cell generator apparatus, characterized by having a layer o~ in~erior insulation, a layer of exterior insulation, and a single housing ha~ing sides placed between the insulation layers, where a plural-ity of ~uel cells containing electrodes and electrolyte are surrounded by the interior insulation, said generator capable of operating at interior temperatures over about 650~C, and said combination o~ interior and exterior insulation layers having the ability to control the temper-ature of the housing below the degradation temperature of the housing material. The housing material could be cast, specialized concrete with appropriate filler materials, molded ceramic, a variety o~ low-cost commercial steels, or the like. The housing will be a single, discrete (includ-ing composite or laminated) layer, ~or example, molded ceramic or concrete, with an optional, thin, contacting stainless or carbon steel exterior sheeting component.
Using a combination of interior and exterior insulation, to control ~uel cell generator housing temperature, allows cost and per~ormance advantages, even though the interior insulation may be unprotected, by an interior housing, cannister or the like, against contacting gaseous fuel and fuel combustion products and lose substantial insulating properties. The fuel cells will generally operate at temperatures over about 650~~, usually over about 650~C and up to about 1250~C. The housing configuration can be square, circular or other geometry, and the ~uel cells can operate in the "pressurized" mode, that is over about 2 atmospheres, or about 28.5 pounds per sq. inch (2.0 kg/sq.cm).
The invention also broadly resides in a sel~-cooling, mono-~ontainer fuel cell generator apparatus characterized by having: a layer of interior insulation;
a layer o~ exterior insulationi and a single metal housing W O 98/29917 PCTrUS96t~0749 having top, bottom and side sections with at least the siae section of the housing disposed between the insulation layers, said side section having cooling ducts therein, which ducts in the side section communicate to a source of cooling liquid or gas; a plurality of fuel cells containing electrodes and electrolyte surrounded by the interior insulation; a gaseous oxidant inleti and a gaseous fuel inlet connected to fuel channels to allow fuel passage to the fuel cells. Here, gaseous oxidant channels ~rom the oxidant inlet can connect to the cooling ducts to allow gaseous oxidant passage through the cooling ducts to the fuel cells, the gaseous oxidant acting as a cooling gas.
In this deslgn, the interior insulation is subject o contact by interior gases; a bottom air plenum connects the oxidant inlet manifold to the cooling ducts, which ducts communicate with a top air plenum which can pass gaseous oxidant to the fuel cells; and an ejector can pass fuel from the fuel inlet to the fuel cells. In both described generators, tubular, flat plate and other type high temper-ature fuel cells can be utilized within the mono-container, and a variety of solid, liquid, matrix electrolytes can be used with the fuel cells. These generators eliminate use of dual housings; substantially reducing cost and space requirements.
The generator can operate at interior temperatures up to about 1250~C in a flow of fuel, and oxidant such as oxygen or air, and will also have associated with it and working in cooperation with at least three well known auxiliaries, such as controls; an oxygen or air pre-heater;
a fuel gas compressor; a fuel desul~urizer; an oxygen or air compressor which may be operably connected to a tur-bine; a source of fuel gas; heat exchangers; and a heat recovery unit to recover heat from the hot fuel cell exhaust gases; and a topping combustor, to provide an electrical power generation system.
The invention also resides in a power generation system characterized by containing a plurality of self-cooling, mono-container fuel cell generator apparatus, each WO 98/29917 PCT~US96/20749 generator having: a layer of interior insulation; a laye~
of exterior insulation; a single metal housing between the insulation layers, the housing containing top, bottom and side sections, the side section o~ the housing havins S cooling ducts therein; a plurality of fuel cells surrounded by the interior insulation; a fuel inlet and fuel transfer ~hAnnels connecting to the fuel cells; and an oxidant inlet and oxidant transfer channels connecting to the fuel cells;
where the plurality o~ generators are positioned next t-each other to provide a close packed array of generators, each generator capable o~ operating at interlor tempera-tures over about 700~C, said array having exterior genera-tor housing side sections and interior generator housina side sections, and where the interior side sections can be cooled by gas or liquid passing through the cooling ducts at the boundary of the interior side sections of the array.
This type power system could be, for example, part of an integrated, coal gasification/fuel cell-steam turbine combination power plant, featuring a plurality of coal gasifiers and fuel cell generator arrays or power blocks with associated DC/AC conversion switchgear. This system solves overheating problems associated with an array of close packed generators, and results in substantial inter-nal cost and space savings.
: BRIEF DESCRIPTION OF THE DR~WINGS
For a better understanding of the invention, reference may be made to the preferred, non-limiting e~bodiments exemplary of the invention, shown in the following drawings, in which:
F~G. l, which best shows the invention, is a three dimensional, cut away view of one embodiment of a single fuel cell generator, having a ~ono-container whose cooling is controlled by a comblr.a~lon of interior and exterior insulation;
FIG. 2 is a three ~:~ensional, cut away view of another embodiment of a s~ngle ~uel cell generator, having a mono-container with interna,, integral cooling ducts, W O98/29917 PCT~US96/20749 whose cooling is controlled by the combination of cooling ducts and interior and exterior insulation;
FIG. 3 shows a three dimensional, cut away view of one embodiment of the mono-container of FIG. 2, at a slightly different angle for illustrative purposes, more D clearly showing the internal cooling ducts and internal insulation of the generator;
FIG. 4 shows a cross sectional view through line 4-4 of the fuel cell generator of FIG. 2, showing the fuel cells, the internal cooling ducts of the mono-container, the interior and exterior insulation, and fuel inlet piping;
FIG. 5 shows a cross-sectional view of the fuel cell generator of FIG. 2, showing oxidant and fuel flow paths;
FIG. 6 shows a partial cross-sectional view of one embodiment of an array of ten close packed mono-container generators which provides a compact power block of up to 1.5 MW capacity, with cooling by means of interior and exterior insulation, and oxidant cooling ducts in the interior of the array as well as around the periphery of the array; and FIG. 7 shows one embodiment of a 300 MW integrated coal gasification/fuel cell-steam turbine power plant, utilizing a plurality of power blocks, such as shown in FIG. 6.
DESCRIPTION OF THE PREFERRED FMBODIMENTS
Referring now to FIG. 1 of the drawings, one type of fuel cell generator 10 is shown. The tubular design would make it particularly useful for fuel cell operation at over atmospheric pressures. The interior 12 of the generator 10 would contain a plurality of fuel cells (not shown) which could be of various configurations, for example, flat, corrugated, or tubular, utilizing a variety of electrolytes operable at relatively high temperatures, for example, a phosphoric acid matrix or a solid oxide ceramic, disposed between electrodes, such as air elec-trodes (the electrode contacted ~y oxidant such as air) and fuel electrodes (the electrode contacted by ~uel, such as reformed coal gas or reformed natural gas). The fuel cells would have associated interconnections and power leads, feed oxidant trans~er tubing, feed fuel transfer tubing, and the like. These fuel cells are surrounded by interior insulation layer 14. Exterior insulation layer 16 sur-rounds at least the sides 18 of the generator housing 20 (here shown as concrete) and will usually also cover the top 22 of the generator housing. The embodiment of the housing shown in FIG. 1 is a "composite", including the main housing 20 of, for example, specialized concrete, such as carbon fiber reinforced concrete or ceramic fiber reinforced concrete for higher temperatures applications, with an optional, contacting, thin sheet of metal such as steel 20', with possible rib or top side reinforcements (not shown). The housing, even if one or more thin compo-nent sheets 20~ are used, is still defined herein as a single housing or mono-container. There i3 no rnajor insulation layer between the main housing 20 and any associated optional steel sheets 20'. Pre~erably, there is no metal layer or other inner layer interior to and sand-wiching insulation layer 14 of the FIG. l embodiment.
The interior insulation may be in contact with hot fuel gas, mixtures of reacted oxidant and fuel, and possi-bly hot oxidant gas, at various places within the genera-tor, at temperatures up to 1250~C and possibly at pressures from 28.5 p8i up to 220 psi. (2.0 kg/sq cm up to 15.5 kg/sq cm). As a result, the insulation must be selected from a limited set of materials that can withstand these tempera-tures and still provide adequate thermal protection for thehousing. The insulation generally should be substantially silica-free to avoid possible silica contamination of the fuel cells, especially SOFC, that could potentially degrade perfor~ance. Therefore, the interior insulation 14 should be, preferably, of a type of high purity alumina fibers.
This alumina material provides good insulation properties, and is available in high purity where silica is minimized.
This alumina insulation is quite porous, and does lose some W O98/29917 PCTrUS96/20749 insulating properties when it becomes exposed to reformed ~uel found in the typical fuel cell stack.
The exterior insulation 16 can be silica, fiber-glass, alumina, or the like, and it will general~y be exposed to ambient air. In order ~or the combination of ~ interior and exterior insulation to cooperate to control fuel cell generator housing temperature to that below the degradation temperature of the housing material, the thickness ratio of (interior insulation):(exterior insula-tion) should generally be from about (1):(.2) to (1):(3).
In experimental operations, a ratio of (1):(.35) is uti-lized. It is desirable to have the housing 20 which can be concrete, concrete-metal composite, metal such as steel, or ceramic, at the lowest safe operating temperature to minimize the quantity of the expensive interior insulation.
The interior insulation is generally more expensive due to the preferred high purity requirements. The total thick-ness required for 14 and 20 is determined by overall heat loss permitted, and the desired thermal efficiency of the fuel cell stack. Active cooling of the structural barrier 20 provides an additional feature of the design. The cooling can easily control the temperature of 20 because of the relatively large thermal resistance of interior insula-tion 14. The coolant could be incoming air used to supply the fuel cell stack, a separate cooling source such as water, chemicals or gases which have to be heated anyway for use or treatment, and thus, just about any liquid or gas economically available.
As mentioned previously, the fuel cells used inside the generator shown in FIG. 1 or FIG. 2 can be solid oxide electrolyte or molten carbonate fuel cells of any type or configuration. However, for purposes of simplic-ity, tubular, solid oxide electrolyte fuel cells will be discussed as an exemplary type useful in this invention,~ 35 and the description hereinafter will generally relate to that type, which shall in no way be considered limiting as to the scope of the invention.
PC~nUS96/207~9 Solid oxide fuel cells (SOFC) are highly efficier_ devices that convert chemical energy into electricity.
They operate at atmospheric or elevated pressures at a temperature of approximately 1000~C to produce electricity using a variety of fossil fuels such as coal derived fuel gas, natural gas, or distillate fuel. The temperature of the exhaust gases from the cells is between 500~C to 850OC, a temperature which is attractive for cogeneration applica-tions or for use in bottoming cycles for all-electric central station power plants.
An operating SOFC readily conducts oxygen ions from an air electrode (cathode), where they are formed, through a solid electrolyte to a fuel electrode (anode) There they react with carbon monoxide (CO) and hydrogen (H-;
contained in the fuel gas to deliver electrons and produce electricity. The tubular SOFC features a porous air electrode made of doped lant~Anl~ manganite. A gas-tigh~
electrolyte of yttria-stabilized zirconia (approximately 40 micrometers thick) covers the air electrode, except in a 6trip about 9mm wide along the entire active cell length.
This strip of exposed air electrode is covered by a thin, dense, gas tight layer of doped lanthanum chromite. This layer, termed the cell interconnection, serves as the electric contacting area to an adjacent cell or to a power contact. The fuel electrode is a nickel-zirconia cermet and covers the electrolyte surface except in the vicinity of the interconnection.
For operation, air is introduced into the fuel cell, generally through an air injector tube. The air, discharged near the closed end of the cell, flows through the annular space formed by the cell and its coaxial injector tu~e. Fuel flows on the outside of the cell.
Typically, 85~ of the fuel is electrochemically utilized (reacted~ in the active fuel cell section. The gas-imper-vious electrolyte does not allow ~itrogen to pass from theair side to the fuel side, hence the fuel is oxidized in a nitrogen free environment, averting the formation of NOx At the open end of the cell, the r~m~i n i ng fuel is reacted PCT~S96/20749 with the alr stream exiting ~he cell, thereby providing additional useful heat. Reformation of natural gas and other fuels containing hydrocarbons can be accomplished, if desired, within the generator. Incoming fuel can be re~ormed to H2 and C0 within the generator, eliminating the need for an external re~ormer. All the gas flows and reactions are controlled within the generator apparatus.
To construct an electric SOFC generator, indivi-dual cells are "bundledl' into an array of series-parallel electrically connected ~uel cells, forming a semi-rigid structure that i9 a basic generator building block. The individual bundles are arrayed in series or parallel to build generator voltage or current, depending on the applica~ion, and to form submodules. ~he parallel electri-cal connection of the cells within a bundle enhances generator reliability. Submodules are further combined in either parallel or series connections to form the generator module. For a more complete description of tubular fuel cells and their operation in a generator apparatus, refer-ence can be made to U.S. Patent No. 4,395,468 ~Isen~erg).
Referring now to FIG. 2 of the drawings, another embodiment of a fuel cell generator 10 is shown. Exterior insulation layer 16 surrounds at least the sides of the generator housing 20, which can be made solely of iron, steel, stainless steel, nickel alloy or other suitable metal. The generator is devoid of an interior cylinder, cannister, or wall adjacent to and interior of the interior insulation 14. The exterior insulation 16 usually also covers the top 22 of the generator housing as shown. Also shown is an oxidant distribution manifold 24, where, for example, air can be fed into the bottom of the generator.
Combusted exhaust gas manifold 26 can exit spent fuel and spent oxidant. A fuel, such as previously described, can be fed to the top of the generator through a ~uel inlet . 35 means, such as piping 28. A cut away section of the top 22, shows top housing 20 with integral cooling ducts 30 and also, interior insulation 14.
CA 02247466 l998-08-2l WO98/29917 12 PCT/US96t20749 A detailed drawing of the bottom part of the housing 20 is shown in ~IG. 3. This housing 20 is a self-cooling, mono-container type, holding interior insulation 14. The housing 20 has at least its sides disposed between interior and exterior insulation, as shown in FIG. 2 and in FIG 4. Cooling ducts 30 are shown in the sides of the housing 20, preferably surrounding the housing as shown.
In one em~odiment of the invention, shown in FIG. 3, the bottom of these cooling ducts 30 csmml-n;cate to a gaseous oxidant inlet, such as the low~r air plenum 32, from the oxidant distribution manifold 24. The interior 12 in FIG. 3 of the generator would contain a plurality of fuel cells, as discussed previously, surrounded by the interior insulation 14. A gaseous fuel inlet from the fuel inlet piping 28 could connect to fuel trans~er channels, to allow fuel passage to the outside of the fuel cells. Gaseous oxidant trans~er channels feed through the cooling ducts 30 to the top of the cooling ducts, to allow passage of oxidant to the interior of the fuel cells. The description of FIG. 4 and FIG. 5 will furcher detail these oxidant and fuel passages described in this embodiment of the in~ren-tion. Of course oxidant may be fed directly to the fuel cells similarly to the fuel, and cooling can be accom-plished by continuous flow o:E water or other liquids or gases. The interior insulation in all cases is subject to contact by interior gaces. The housing 20 in all cases in FIG. 3 is shown as a rounded off square, but it can be other con~igurations, for example the side sections could be a continuous tube.
FIG. 4 is a cross section of the insulated generator of FIG. 2 along line 4-4, showing fuel cell bundles 34, each bundle contains a plurality of inter-connected fuel cells 36, here shown as of the tubular SOFC
type, with electrodes and sandwiched electrolyte. The housing 20, surrounded by interior insulation 14 and exterior insulation 16, contains cooling ducts 30, pre~era-bly around its periphery. There is no interior housing, metal or other wall or structure contacting interior CA 02247466 l99X-08-21 W O98/29917 13 PCTrUS96/20749 insulation 14. The housing 20 does not sandwich the interior insulation 14 between an interior cannister or other member. Fuel would enter fuel inlet piping 28 and - pass, preferably to one or more ejectors 38, which are better shown in FIG. 5, where recirculation gases may inject-mix with feed fuel, to provide a stream useful in the reforming section 40 and to otherwise provide optimal operating conditions. The fuel stream 42 then exits reformer 40 and passes through a fuel plenum 44 and into fuel supply lines which transfer or pass at least partly re~ormed fuel to the outside of fuel cells 36, as shown in FIG. S, where the fuel reacts along the elongated fuel electrode surface on the exterior of the tubular fuel cells 36.
As shown in FIG. 5, oxidant enters air plenum 32 as oxidant stream 48 passing upward through cooling ducts 30 to a top air distribution plenum 50. The oxidant stream then is transferred and passes downward via individual oxidant feed tubes 52 into the bottom interior of each fuel cell 36, where, as is well known in the art, the oxidant reverses flow and passes in the annular space between the oxidant feed tube and the interior air electrode, where it reacts along the air electrode interior sur~ace. The reacted oxidant finally enters a combustion section 54 (flow not shown) as spent oxidant. The spent oxidant then combusts with spent fuel to pro~ide exhaust gas 56, part of which may be recirculated to the ejector 38. The rest of the exhaust 56 gas passes through exhaust ducts 58 into the exhaust gas manifold 26, shown in FIG. 2. Further details on these flow patterns as well as use of an ejector system can be found in U.S. Patent No. 5,169,730 (Reichner).
Referring now to FIG. 6 of the drawings, an array 60 o~ ten, insulated, mono-containers are shown as provid-ing a power block. As can be seen, the housings 20, '35 containing cooling ducts 30, are surrounded by exterior insulation 16 (fuel cell generator internals are not shown for the sake of clarity). Exterior generator side sections 62, as well as interior side sections 64 can be cooled by W O98/29917 PCTnUS96/20749 gaseous oxidant passage through the cooling ducts 30. This cooling ls especially important at the center interior portions 66 of the array 60, solving overheating problems associated with a close packed generator array and allowing use of a wider section of steels ~or the container housings 20. Without cooling between the modules, the space between modules would reach stack temperatures of 1000~C or over.
Stable metallic structures for long term use at these temperatures might require exotic, very expensive alloys.
The exhaust gas mani~olds 26, shown more clearly in FIG. 2 are shown connected together from generator to generator.
Fuel feed piping 28 is also shown connected.
FIG. 7 depicts a 300 MW, integrated coa gasification/~uel cell steam turbine power plant 70. Coa gasification unit 72, air separation (oxygen) plant 74, DC/AC conversion and electrical switch gear and powe-conditioning unit 76 are shown, along with five, 50,000-tor.
coal storage silos 78. The ~uel ~eed from the coal gasi~i-cation units can operate eight SOFC power block arrays 60, described previously, each containing 12 SOFC generators or modules, which in turn are associated with a heat recovery steam turbine 80 and heat recovery steam generator 82. As can be seen, the SOFC blocks can be integrated into a system utilizing a turbine.
In a pressurized SOFC power block system, described previoucly, a compressor could compress pre-heated air which could be supplied to the ~uel cells. The hot gas from the power blocks could be pumped at higr.
pressure to a combustor, producing further heated hot gas that could be expanded in a turbine to produce power. The turbine could in turn run a compressor for pressurizing the oxidant stream, as in U.S. ~atent No. 3,972,73i (Bloomfield et al.). Also, in a press~r zed SOFC power block, the hot gas ~rom the power blocks colld be directed to a turbine by way of a ~opping combustor ~.~at is supplied with ~uel, to produce a still ~urther hea~ed ~.ot gas that is then passed to and expanded in a turblne apparatus as in U.S. Patent No. 5,413,879 (Domeracki et al.). In the integrated gas W O 98/29917 PCTrUS96/20749 turbine/soiid oxide fuel cell system, the ma~or components of the sys~em would be a compressor, a tu_bine, a ro~or by whic:- tne turbine drives the compresso~ as well as an elect-ical generator, a fuel pre-hea~e-, an air pre-heate-, a fuel desulfurizer, a solid oxide fuel cell generatcr with a combustion chamber, a topping combusto- and an exhaust stack.
In opera~ion, the compressor, wnich includes rows of stationary vanes and rotating blades, inducts ambient air and produces c_mpressed air. The compressed air, after flowing through a topping combustor, is heated by the air pre-heater. The air pre-heate-, which may be of the -inned tube type, has hea= ~-ansrer surfaces tha. -llow heat to be transfe-red from the ~urbine exhaust gas aischarged by the fuei pre-heater, to the compressed air, ~hereby producing heated compressed air. The compressed ai_ can be heated into approximately the 500~C-600~C. The heated compressed air is then directed to the solid oxide fuel cell genera-tor. Gaseous fuel, which may be natural gas or a coal derived fuel gas, is driven by a pump through the fuel pre-heater. The fuel pre-heate~, which may be of the _inned tube type, has hea~ transfe~ surfaces thar allow heat to be transfe-red from the exhaust gas discharged by the ~lrbine to the ~uel, -hereby producing neated ~ue;. The ~~uel can be hea~ed to approximately 400~C. The hea~ed fuel is then dire-ted to a desulfurize~, which may comprise a vessel containing a bed c- sulfur sorDent through which the fuel flows. The fuel exiting from the desulfurizer, preferably, has less than 0.1 ppm of sulfur.
While FIG. 6 and FIG. 7 have been generally desc-ibed using SOFC, other types of fuel cell could be ~ used ln such systems, as described previously. This is only one design that could use the close packed power block arrays of this invention. They are also applicable to SOFC
cogeneration systems utilizing steam from boilers; liqui-fied natural gas rueled SOFC, all electri~ power plants;
repowering of exis ing fossil fuel power plantsi and navel ship elec~-lcal propulsion.
The use of the self cooled mono-container power block arrays of this invention allows atmospheric or pressurized utilization of commercial SOFC's and have advantages of:
~ As high as 80~ overall efficiency (50~ electri-cal) ~or cogeneration applications and greater than 50~ for natural gas fueled central station power plants.
~ Where sul~ur is removed from the ~uel, no SOx is emitted. Because temperatures are only moderately high, NOx emissions have been measured at and may be less than 0.5 ppm.
~ Low emissions, quiet and low vibration opera-tion, and fuel flexibility permit installation of SOFC
systems near load centers or in urban areas.
~ Rapid response to load change over a broad power range and high ef~iciency at part load operation would satisfy the requirements of the commercial, indust-rial and utility markets.
~ operating flexibility can produce exhaust temperatures compatible with generating high quality steam for bottoming cycles or for cogeneration systems.
~ Cooling with process air eliminates the requirement for separate liquid or liquid/air cooling loops and the solid electrolyte eliminates the problems associ-ated with the management of liquid electrolytes.
~ Modular construction and availability o~
factory produced SOFC modules will allow the user to respond to load growth demands while minimizing capital exposure.
AND POWER PLANTS USING AN ARRAY OF SUCH GENERATORS
GOVERNMENT CONTRACT
The Government of the United States of America has rights in this invention, pursuant to Contract No. DE-FC21-slMC28055 with the United States Department of Energy.
FIELD OF TH~ INVENTION
The invention relates to heat controlled, solid oxide electrolyte, fuel cell generators, and to an array of such generators disposed in a mono-container shell, for use with a variety of auxiliary components in a power genera-tion system of the 100kW to 50MW plus capacity.
BACKGROUND AND SUMMARY OF THE INVENTION
Fuel cell based, electrical generator apparatus ("generators") utilizing solid oxide electrolyte fuel cells ("SOFC") disposed within a housing and surrounded by insulation are well known, and taught, for example, by U.S.
Patent Nos: 4,395,468 (Isenberg) and "Solid Oxide Fuel Cell", Westinghouse Electric Corporation, October 1992, for tubular SOFC; 4,476,196 (Poppel, et al.~ for flat plate SOFC; and 4,476,198 (Ackerman, et al.) for "corrugated"
SOFC, all herein incorporated by reference. The tubular type fuel cells can comprise an open or closed ended, axially elongated, ceramic tube air electrode material, which can be deposited on a ceramic support tube, com-pletely covered by thin film ceramic, solid electrolyte material. The electrolyte is substantially covered by cermet fuel electrode material, except for a thin, axially elongated, interconnection material. The flat plate type W O 98/29917 2 PCT~S96/20749 ~uel cells can comprise a flat array o~ electrolyte a-d interconnect walls, where electrolyte walls contain thin, flat layers of cathode and anode materials sandwiching an electrolyte. The "corrugated" plate type fuel cells can comprise a triangular or corrugated honeycomb array of active anode, cathode, electrolyte and interconnect mate-rials. Other fuel cells not having a solid electrolyte, such molten carbonate fuel cells are also well known, and can be insulated using the mono-container of this inven-tion.
In construction of ~uel cell generators, stable insulation was thought essential, and both interior and exterior steel housing shells, with the high temperature insulation between them, were thought important to protect lS the insulation from hydrogen gas or other fuel gas permea-tion, which could cause loss of insulating gases from the insulation pores, as taught in U.S. Patent No. 4,640,875 (Makiel). Appropriate seals for a two part intericr housing are also taught in that patent, allowing for radial and longitudinal expansion o~ the interior housing during thermal cycling and operation o~ the generator. Use of an inner metal canister to protect a certain portion of the insulation, and act as one wall o~ corner heating condui~s is taught in U.S. Patent No. 4,808,491 (Reichner). This aual metal housing design was the primary configuration r~-experimental 2SkW generators. In all cases, insulation was disposed on the inside of the exterior metal housing.
In previous designs, the oxidant air ~eed manifold system, which could be similar to that shown in U.S. Patent No. 4,664,986 (Draper et al.), and portions of the inner metal canister, were contacted with reacted, depleted oxidant/fuel hot exhaust gases in a combustion chamber, which resulted in high interior metal housing temperatures.
High metal housing temperatures can be handled for a single generator by using exotic steels and ceramic materials.
However, for commercial applications, where an array of multiple generators might be electrically connected to provide MW system output, active cooling would be required CA 02247466 l998-08-2l on sides of those generators not located on the periphery of the system. The high cost of specialty steels and ceramics ~or single generators remains a problem, and the ~ problem of cooling the interior of an array of solid oxide fuel cell generators poses serious difficulties not previ-ously addressed. Without such central cooling, buckling and potential failure of cont~inm~nt vessels near the center of the array could result after long operation.
A variety of fuel cell systems are described in the literature. In U.S. Patent No. 3,972,731 (Bloomfield et al.), a pressurized fuel cell power plant is described.
There, air is compressed by compressor apparatus, such as a compressor and turbine which are operably connected, which is powered by waste energy produced by the power plant in the form of a hot pressurized gaseous medium, such as fuel cell exhaust gases. These exhaust gases are delivered into the turbine, which drives the compressor for compressing air delivered to the fuel cells. In U.S.
Patent No. 5,413,879 (Domeracki et al.) a SOFC was also integrated into a gas turbine system. There, pre-heated, compressed air i8 supplied to a SOFC along with fuel, to produce electric power and a hot gas, which gas is further heated by combustion of unreacted fuel and oxygen remaining in the hot gas. This higher temperature gas is directed to a topping combustor that is supplied with a second stream of fuel, to produce a still further heated gas that is then expanded in a turbine.
U.S. Patent No. 4,622,275 (Noguchi et al.) alsc describes a fuel cell power plant, where reformed, reactive fuel is fed to an anode of the cell, an expansion turbine connected to a compressor feeds compressed gas into the cathode of the cell, which compressed gas is mixed with anode exhaust gas which had been combusted.
A~ pointed out previously, in power plant applica-tions, arrays of fuel cell generators, modules, or powerblocks will have to be cooled in the interior of the array to prevent overheating and possible failure o~ non-ceram _ components. Also, to be commercially competitive, ~he W O 98/29917 PCTAUS96/207~9 number of housing shells must be reduced. It is one of the objectives of this invention to provide a heat controlled generator and a cooled array of mono-container generators.
Accordingly, the invention resides ln a self-cooling, mono-container fuel cell generator apparatus, characterized by having a layer o~ in~erior insulation, a layer of exterior insulation, and a single housing ha~ing sides placed between the insulation layers, where a plural-ity of ~uel cells containing electrodes and electrolyte are surrounded by the interior insulation, said generator capable of operating at interior temperatures over about 650~C, and said combination o~ interior and exterior insulation layers having the ability to control the temper-ature of the housing below the degradation temperature of the housing material. The housing material could be cast, specialized concrete with appropriate filler materials, molded ceramic, a variety o~ low-cost commercial steels, or the like. The housing will be a single, discrete (includ-ing composite or laminated) layer, ~or example, molded ceramic or concrete, with an optional, thin, contacting stainless or carbon steel exterior sheeting component.
Using a combination of interior and exterior insulation, to control ~uel cell generator housing temperature, allows cost and per~ormance advantages, even though the interior insulation may be unprotected, by an interior housing, cannister or the like, against contacting gaseous fuel and fuel combustion products and lose substantial insulating properties. The fuel cells will generally operate at temperatures over about 650~~, usually over about 650~C and up to about 1250~C. The housing configuration can be square, circular or other geometry, and the ~uel cells can operate in the "pressurized" mode, that is over about 2 atmospheres, or about 28.5 pounds per sq. inch (2.0 kg/sq.cm).
The invention also broadly resides in a sel~-cooling, mono-~ontainer fuel cell generator apparatus characterized by having: a layer of interior insulation;
a layer o~ exterior insulationi and a single metal housing W O 98/29917 PCTrUS96t~0749 having top, bottom and side sections with at least the siae section of the housing disposed between the insulation layers, said side section having cooling ducts therein, which ducts in the side section communicate to a source of cooling liquid or gas; a plurality of fuel cells containing electrodes and electrolyte surrounded by the interior insulation; a gaseous oxidant inleti and a gaseous fuel inlet connected to fuel channels to allow fuel passage to the fuel cells. Here, gaseous oxidant channels ~rom the oxidant inlet can connect to the cooling ducts to allow gaseous oxidant passage through the cooling ducts to the fuel cells, the gaseous oxidant acting as a cooling gas.
In this deslgn, the interior insulation is subject o contact by interior gases; a bottom air plenum connects the oxidant inlet manifold to the cooling ducts, which ducts communicate with a top air plenum which can pass gaseous oxidant to the fuel cells; and an ejector can pass fuel from the fuel inlet to the fuel cells. In both described generators, tubular, flat plate and other type high temper-ature fuel cells can be utilized within the mono-container, and a variety of solid, liquid, matrix electrolytes can be used with the fuel cells. These generators eliminate use of dual housings; substantially reducing cost and space requirements.
The generator can operate at interior temperatures up to about 1250~C in a flow of fuel, and oxidant such as oxygen or air, and will also have associated with it and working in cooperation with at least three well known auxiliaries, such as controls; an oxygen or air pre-heater;
a fuel gas compressor; a fuel desul~urizer; an oxygen or air compressor which may be operably connected to a tur-bine; a source of fuel gas; heat exchangers; and a heat recovery unit to recover heat from the hot fuel cell exhaust gases; and a topping combustor, to provide an electrical power generation system.
The invention also resides in a power generation system characterized by containing a plurality of self-cooling, mono-container fuel cell generator apparatus, each WO 98/29917 PCT~US96/20749 generator having: a layer of interior insulation; a laye~
of exterior insulation; a single metal housing between the insulation layers, the housing containing top, bottom and side sections, the side section o~ the housing havins S cooling ducts therein; a plurality of fuel cells surrounded by the interior insulation; a fuel inlet and fuel transfer ~hAnnels connecting to the fuel cells; and an oxidant inlet and oxidant transfer channels connecting to the fuel cells;
where the plurality o~ generators are positioned next t-each other to provide a close packed array of generators, each generator capable o~ operating at interlor tempera-tures over about 700~C, said array having exterior genera-tor housing side sections and interior generator housina side sections, and where the interior side sections can be cooled by gas or liquid passing through the cooling ducts at the boundary of the interior side sections of the array.
This type power system could be, for example, part of an integrated, coal gasification/fuel cell-steam turbine combination power plant, featuring a plurality of coal gasifiers and fuel cell generator arrays or power blocks with associated DC/AC conversion switchgear. This system solves overheating problems associated with an array of close packed generators, and results in substantial inter-nal cost and space savings.
: BRIEF DESCRIPTION OF THE DR~WINGS
For a better understanding of the invention, reference may be made to the preferred, non-limiting e~bodiments exemplary of the invention, shown in the following drawings, in which:
F~G. l, which best shows the invention, is a three dimensional, cut away view of one embodiment of a single fuel cell generator, having a ~ono-container whose cooling is controlled by a comblr.a~lon of interior and exterior insulation;
FIG. 2 is a three ~:~ensional, cut away view of another embodiment of a s~ngle ~uel cell generator, having a mono-container with interna,, integral cooling ducts, W O98/29917 PCT~US96/20749 whose cooling is controlled by the combination of cooling ducts and interior and exterior insulation;
FIG. 3 shows a three dimensional, cut away view of one embodiment of the mono-container of FIG. 2, at a slightly different angle for illustrative purposes, more D clearly showing the internal cooling ducts and internal insulation of the generator;
FIG. 4 shows a cross sectional view through line 4-4 of the fuel cell generator of FIG. 2, showing the fuel cells, the internal cooling ducts of the mono-container, the interior and exterior insulation, and fuel inlet piping;
FIG. 5 shows a cross-sectional view of the fuel cell generator of FIG. 2, showing oxidant and fuel flow paths;
FIG. 6 shows a partial cross-sectional view of one embodiment of an array of ten close packed mono-container generators which provides a compact power block of up to 1.5 MW capacity, with cooling by means of interior and exterior insulation, and oxidant cooling ducts in the interior of the array as well as around the periphery of the array; and FIG. 7 shows one embodiment of a 300 MW integrated coal gasification/fuel cell-steam turbine power plant, utilizing a plurality of power blocks, such as shown in FIG. 6.
DESCRIPTION OF THE PREFERRED FMBODIMENTS
Referring now to FIG. 1 of the drawings, one type of fuel cell generator 10 is shown. The tubular design would make it particularly useful for fuel cell operation at over atmospheric pressures. The interior 12 of the generator 10 would contain a plurality of fuel cells (not shown) which could be of various configurations, for example, flat, corrugated, or tubular, utilizing a variety of electrolytes operable at relatively high temperatures, for example, a phosphoric acid matrix or a solid oxide ceramic, disposed between electrodes, such as air elec-trodes (the electrode contacted ~y oxidant such as air) and fuel electrodes (the electrode contacted by ~uel, such as reformed coal gas or reformed natural gas). The fuel cells would have associated interconnections and power leads, feed oxidant trans~er tubing, feed fuel transfer tubing, and the like. These fuel cells are surrounded by interior insulation layer 14. Exterior insulation layer 16 sur-rounds at least the sides 18 of the generator housing 20 (here shown as concrete) and will usually also cover the top 22 of the generator housing. The embodiment of the housing shown in FIG. 1 is a "composite", including the main housing 20 of, for example, specialized concrete, such as carbon fiber reinforced concrete or ceramic fiber reinforced concrete for higher temperatures applications, with an optional, contacting, thin sheet of metal such as steel 20', with possible rib or top side reinforcements (not shown). The housing, even if one or more thin compo-nent sheets 20~ are used, is still defined herein as a single housing or mono-container. There i3 no rnajor insulation layer between the main housing 20 and any associated optional steel sheets 20'. Pre~erably, there is no metal layer or other inner layer interior to and sand-wiching insulation layer 14 of the FIG. l embodiment.
The interior insulation may be in contact with hot fuel gas, mixtures of reacted oxidant and fuel, and possi-bly hot oxidant gas, at various places within the genera-tor, at temperatures up to 1250~C and possibly at pressures from 28.5 p8i up to 220 psi. (2.0 kg/sq cm up to 15.5 kg/sq cm). As a result, the insulation must be selected from a limited set of materials that can withstand these tempera-tures and still provide adequate thermal protection for thehousing. The insulation generally should be substantially silica-free to avoid possible silica contamination of the fuel cells, especially SOFC, that could potentially degrade perfor~ance. Therefore, the interior insulation 14 should be, preferably, of a type of high purity alumina fibers.
This alumina material provides good insulation properties, and is available in high purity where silica is minimized.
This alumina insulation is quite porous, and does lose some W O98/29917 PCTrUS96/20749 insulating properties when it becomes exposed to reformed ~uel found in the typical fuel cell stack.
The exterior insulation 16 can be silica, fiber-glass, alumina, or the like, and it will general~y be exposed to ambient air. In order ~or the combination of ~ interior and exterior insulation to cooperate to control fuel cell generator housing temperature to that below the degradation temperature of the housing material, the thickness ratio of (interior insulation):(exterior insula-tion) should generally be from about (1):(.2) to (1):(3).
In experimental operations, a ratio of (1):(.35) is uti-lized. It is desirable to have the housing 20 which can be concrete, concrete-metal composite, metal such as steel, or ceramic, at the lowest safe operating temperature to minimize the quantity of the expensive interior insulation.
The interior insulation is generally more expensive due to the preferred high purity requirements. The total thick-ness required for 14 and 20 is determined by overall heat loss permitted, and the desired thermal efficiency of the fuel cell stack. Active cooling of the structural barrier 20 provides an additional feature of the design. The cooling can easily control the temperature of 20 because of the relatively large thermal resistance of interior insula-tion 14. The coolant could be incoming air used to supply the fuel cell stack, a separate cooling source such as water, chemicals or gases which have to be heated anyway for use or treatment, and thus, just about any liquid or gas economically available.
As mentioned previously, the fuel cells used inside the generator shown in FIG. 1 or FIG. 2 can be solid oxide electrolyte or molten carbonate fuel cells of any type or configuration. However, for purposes of simplic-ity, tubular, solid oxide electrolyte fuel cells will be discussed as an exemplary type useful in this invention,~ 35 and the description hereinafter will generally relate to that type, which shall in no way be considered limiting as to the scope of the invention.
PC~nUS96/207~9 Solid oxide fuel cells (SOFC) are highly efficier_ devices that convert chemical energy into electricity.
They operate at atmospheric or elevated pressures at a temperature of approximately 1000~C to produce electricity using a variety of fossil fuels such as coal derived fuel gas, natural gas, or distillate fuel. The temperature of the exhaust gases from the cells is between 500~C to 850OC, a temperature which is attractive for cogeneration applica-tions or for use in bottoming cycles for all-electric central station power plants.
An operating SOFC readily conducts oxygen ions from an air electrode (cathode), where they are formed, through a solid electrolyte to a fuel electrode (anode) There they react with carbon monoxide (CO) and hydrogen (H-;
contained in the fuel gas to deliver electrons and produce electricity. The tubular SOFC features a porous air electrode made of doped lant~Anl~ manganite. A gas-tigh~
electrolyte of yttria-stabilized zirconia (approximately 40 micrometers thick) covers the air electrode, except in a 6trip about 9mm wide along the entire active cell length.
This strip of exposed air electrode is covered by a thin, dense, gas tight layer of doped lanthanum chromite. This layer, termed the cell interconnection, serves as the electric contacting area to an adjacent cell or to a power contact. The fuel electrode is a nickel-zirconia cermet and covers the electrolyte surface except in the vicinity of the interconnection.
For operation, air is introduced into the fuel cell, generally through an air injector tube. The air, discharged near the closed end of the cell, flows through the annular space formed by the cell and its coaxial injector tu~e. Fuel flows on the outside of the cell.
Typically, 85~ of the fuel is electrochemically utilized (reacted~ in the active fuel cell section. The gas-imper-vious electrolyte does not allow ~itrogen to pass from theair side to the fuel side, hence the fuel is oxidized in a nitrogen free environment, averting the formation of NOx At the open end of the cell, the r~m~i n i ng fuel is reacted PCT~S96/20749 with the alr stream exiting ~he cell, thereby providing additional useful heat. Reformation of natural gas and other fuels containing hydrocarbons can be accomplished, if desired, within the generator. Incoming fuel can be re~ormed to H2 and C0 within the generator, eliminating the need for an external re~ormer. All the gas flows and reactions are controlled within the generator apparatus.
To construct an electric SOFC generator, indivi-dual cells are "bundledl' into an array of series-parallel electrically connected ~uel cells, forming a semi-rigid structure that i9 a basic generator building block. The individual bundles are arrayed in series or parallel to build generator voltage or current, depending on the applica~ion, and to form submodules. ~he parallel electri-cal connection of the cells within a bundle enhances generator reliability. Submodules are further combined in either parallel or series connections to form the generator module. For a more complete description of tubular fuel cells and their operation in a generator apparatus, refer-ence can be made to U.S. Patent No. 4,395,468 ~Isen~erg).
Referring now to FIG. 2 of the drawings, another embodiment of a fuel cell generator 10 is shown. Exterior insulation layer 16 surrounds at least the sides of the generator housing 20, which can be made solely of iron, steel, stainless steel, nickel alloy or other suitable metal. The generator is devoid of an interior cylinder, cannister, or wall adjacent to and interior of the interior insulation 14. The exterior insulation 16 usually also covers the top 22 of the generator housing as shown. Also shown is an oxidant distribution manifold 24, where, for example, air can be fed into the bottom of the generator.
Combusted exhaust gas manifold 26 can exit spent fuel and spent oxidant. A fuel, such as previously described, can be fed to the top of the generator through a ~uel inlet . 35 means, such as piping 28. A cut away section of the top 22, shows top housing 20 with integral cooling ducts 30 and also, interior insulation 14.
CA 02247466 l998-08-2l WO98/29917 12 PCT/US96t20749 A detailed drawing of the bottom part of the housing 20 is shown in ~IG. 3. This housing 20 is a self-cooling, mono-container type, holding interior insulation 14. The housing 20 has at least its sides disposed between interior and exterior insulation, as shown in FIG. 2 and in FIG 4. Cooling ducts 30 are shown in the sides of the housing 20, preferably surrounding the housing as shown.
In one em~odiment of the invention, shown in FIG. 3, the bottom of these cooling ducts 30 csmml-n;cate to a gaseous oxidant inlet, such as the low~r air plenum 32, from the oxidant distribution manifold 24. The interior 12 in FIG. 3 of the generator would contain a plurality of fuel cells, as discussed previously, surrounded by the interior insulation 14. A gaseous fuel inlet from the fuel inlet piping 28 could connect to fuel trans~er channels, to allow fuel passage to the outside of the fuel cells. Gaseous oxidant trans~er channels feed through the cooling ducts 30 to the top of the cooling ducts, to allow passage of oxidant to the interior of the fuel cells. The description of FIG. 4 and FIG. 5 will furcher detail these oxidant and fuel passages described in this embodiment of the in~ren-tion. Of course oxidant may be fed directly to the fuel cells similarly to the fuel, and cooling can be accom-plished by continuous flow o:E water or other liquids or gases. The interior insulation in all cases is subject to contact by interior gaces. The housing 20 in all cases in FIG. 3 is shown as a rounded off square, but it can be other con~igurations, for example the side sections could be a continuous tube.
FIG. 4 is a cross section of the insulated generator of FIG. 2 along line 4-4, showing fuel cell bundles 34, each bundle contains a plurality of inter-connected fuel cells 36, here shown as of the tubular SOFC
type, with electrodes and sandwiched electrolyte. The housing 20, surrounded by interior insulation 14 and exterior insulation 16, contains cooling ducts 30, pre~era-bly around its periphery. There is no interior housing, metal or other wall or structure contacting interior CA 02247466 l99X-08-21 W O98/29917 13 PCTrUS96/20749 insulation 14. The housing 20 does not sandwich the interior insulation 14 between an interior cannister or other member. Fuel would enter fuel inlet piping 28 and - pass, preferably to one or more ejectors 38, which are better shown in FIG. 5, where recirculation gases may inject-mix with feed fuel, to provide a stream useful in the reforming section 40 and to otherwise provide optimal operating conditions. The fuel stream 42 then exits reformer 40 and passes through a fuel plenum 44 and into fuel supply lines which transfer or pass at least partly re~ormed fuel to the outside of fuel cells 36, as shown in FIG. S, where the fuel reacts along the elongated fuel electrode surface on the exterior of the tubular fuel cells 36.
As shown in FIG. 5, oxidant enters air plenum 32 as oxidant stream 48 passing upward through cooling ducts 30 to a top air distribution plenum 50. The oxidant stream then is transferred and passes downward via individual oxidant feed tubes 52 into the bottom interior of each fuel cell 36, where, as is well known in the art, the oxidant reverses flow and passes in the annular space between the oxidant feed tube and the interior air electrode, where it reacts along the air electrode interior sur~ace. The reacted oxidant finally enters a combustion section 54 (flow not shown) as spent oxidant. The spent oxidant then combusts with spent fuel to pro~ide exhaust gas 56, part of which may be recirculated to the ejector 38. The rest of the exhaust 56 gas passes through exhaust ducts 58 into the exhaust gas manifold 26, shown in FIG. 2. Further details on these flow patterns as well as use of an ejector system can be found in U.S. Patent No. 5,169,730 (Reichner).
Referring now to FIG. 6 of the drawings, an array 60 o~ ten, insulated, mono-containers are shown as provid-ing a power block. As can be seen, the housings 20, '35 containing cooling ducts 30, are surrounded by exterior insulation 16 (fuel cell generator internals are not shown for the sake of clarity). Exterior generator side sections 62, as well as interior side sections 64 can be cooled by W O98/29917 PCTnUS96/20749 gaseous oxidant passage through the cooling ducts 30. This cooling ls especially important at the center interior portions 66 of the array 60, solving overheating problems associated with a close packed generator array and allowing use of a wider section of steels ~or the container housings 20. Without cooling between the modules, the space between modules would reach stack temperatures of 1000~C or over.
Stable metallic structures for long term use at these temperatures might require exotic, very expensive alloys.
The exhaust gas mani~olds 26, shown more clearly in FIG. 2 are shown connected together from generator to generator.
Fuel feed piping 28 is also shown connected.
FIG. 7 depicts a 300 MW, integrated coa gasification/~uel cell steam turbine power plant 70. Coa gasification unit 72, air separation (oxygen) plant 74, DC/AC conversion and electrical switch gear and powe-conditioning unit 76 are shown, along with five, 50,000-tor.
coal storage silos 78. The ~uel ~eed from the coal gasi~i-cation units can operate eight SOFC power block arrays 60, described previously, each containing 12 SOFC generators or modules, which in turn are associated with a heat recovery steam turbine 80 and heat recovery steam generator 82. As can be seen, the SOFC blocks can be integrated into a system utilizing a turbine.
In a pressurized SOFC power block system, described previoucly, a compressor could compress pre-heated air which could be supplied to the ~uel cells. The hot gas from the power blocks could be pumped at higr.
pressure to a combustor, producing further heated hot gas that could be expanded in a turbine to produce power. The turbine could in turn run a compressor for pressurizing the oxidant stream, as in U.S. ~atent No. 3,972,73i (Bloomfield et al.). Also, in a press~r zed SOFC power block, the hot gas ~rom the power blocks colld be directed to a turbine by way of a ~opping combustor ~.~at is supplied with ~uel, to produce a still ~urther hea~ed ~.ot gas that is then passed to and expanded in a turblne apparatus as in U.S. Patent No. 5,413,879 (Domeracki et al.). In the integrated gas W O 98/29917 PCTrUS96/20749 turbine/soiid oxide fuel cell system, the ma~or components of the sys~em would be a compressor, a tu_bine, a ro~or by whic:- tne turbine drives the compresso~ as well as an elect-ical generator, a fuel pre-hea~e-, an air pre-heate-, a fuel desulfurizer, a solid oxide fuel cell generatcr with a combustion chamber, a topping combusto- and an exhaust stack.
In opera~ion, the compressor, wnich includes rows of stationary vanes and rotating blades, inducts ambient air and produces c_mpressed air. The compressed air, after flowing through a topping combustor, is heated by the air pre-heater. The air pre-heate-, which may be of the -inned tube type, has hea= ~-ansrer surfaces tha. -llow heat to be transfe-red from the ~urbine exhaust gas aischarged by the fuei pre-heater, to the compressed air, ~hereby producing heated compressed air. The compressed ai_ can be heated into approximately the 500~C-600~C. The heated compressed air is then directed to the solid oxide fuel cell genera-tor. Gaseous fuel, which may be natural gas or a coal derived fuel gas, is driven by a pump through the fuel pre-heater. The fuel pre-heate~, which may be of the _inned tube type, has hea~ transfe~ surfaces thar allow heat to be transfe-red from the exhaust gas discharged by the ~lrbine to the ~uel, -hereby producing neated ~ue;. The ~~uel can be hea~ed to approximately 400~C. The hea~ed fuel is then dire-ted to a desulfurize~, which may comprise a vessel containing a bed c- sulfur sorDent through which the fuel flows. The fuel exiting from the desulfurizer, preferably, has less than 0.1 ppm of sulfur.
While FIG. 6 and FIG. 7 have been generally desc-ibed using SOFC, other types of fuel cell could be ~ used ln such systems, as described previously. This is only one design that could use the close packed power block arrays of this invention. They are also applicable to SOFC
cogeneration systems utilizing steam from boilers; liqui-fied natural gas rueled SOFC, all electri~ power plants;
repowering of exis ing fossil fuel power plantsi and navel ship elec~-lcal propulsion.
The use of the self cooled mono-container power block arrays of this invention allows atmospheric or pressurized utilization of commercial SOFC's and have advantages of:
~ As high as 80~ overall efficiency (50~ electri-cal) ~or cogeneration applications and greater than 50~ for natural gas fueled central station power plants.
~ Where sul~ur is removed from the ~uel, no SOx is emitted. Because temperatures are only moderately high, NOx emissions have been measured at and may be less than 0.5 ppm.
~ Low emissions, quiet and low vibration opera-tion, and fuel flexibility permit installation of SOFC
systems near load centers or in urban areas.
~ Rapid response to load change over a broad power range and high ef~iciency at part load operation would satisfy the requirements of the commercial, indust-rial and utility markets.
~ operating flexibility can produce exhaust temperatures compatible with generating high quality steam for bottoming cycles or for cogeneration systems.
~ Cooling with process air eliminates the requirement for separate liquid or liquid/air cooling loops and the solid electrolyte eliminates the problems associ-ated with the management of liquid electrolytes.
~ Modular construction and availability o~
factory produced SOFC modules will allow the user to respond to load growth demands while minimizing capital exposure.
Claims (28)
1. A self-cooling, mono-container fuel cell generator apparatus, comprising a layer of interior insulation, a layer of exterior insulation, and a single housing having sides placed between the insulation layers, where a plurality of fuel cells containing electrodes and electrolyte are surrounded by the interior insulation, said generator capable of operating at interior temperatures over about 650°C, and said combination of interior and exterior insulation layers having the ability to control the temperature of the housing below the degradation temperature of the housing material.
2. The mono-container fuel cell generator apparatus of claim 1, also containing means to supply gaseous oxidant to the fuel cells and means to supply gaseous fuel to the fuel cells, where at least one of the supply means is effective to provide pressurized gas to the fuel cells.
3. The mono-container fuel cell generator apparatus of claim 1, where the housing material is selected from the group of concrete, concrete-metal composite, metal, and ceramic, and the thickness ratio of interior insulation:exterior insulation is from about (1):(.2) to about (1):(3).
4. The mono-container fuel cell generator apparatus of claim 1, where the housing integrally contains a plurality of cooling ducts.
5. The mono-container fuel cell generator apparatus of claim 1, where the fuel cells are of tubular fuel cell design and the interior insulation is substantially silica-free.
6. The mono-container fuel cell generator apparatus of claim 1, where the fuel cells are or flat plate fuel cell design.
7. The mono-container fuel cell generator apparatus of claim 1, where the fuel cells are of corrugated monolithic design.
8. The mono-container fuel cell generator apparatus of claim 1, having associated with it at least three auxiliaries selected from controls, oxygen or air pre-heater, fuel gas compressor, fuel desulfurizer, oxygen or air compressor, turbine, heat exchanger, and topping combustor.
9. A plurality of the mono-container fuel cell generator apparatus of claim 1, positioned next to each other to provide an array of generators, said array having exterior generator housing side sections and interior generator housing side sections, where the interior housing side sections contain cooling ducts for passage of cooling liquid or gas in a manner effective to help cool the interior generator housing side sections.
10. A plurality of mono-container fuel cell generator apparatus of claim 9, where a compressor means to pressurize at least one of oxidant and fuel is associated with the fuel cells and the generator apparatus contains hot exit gas means which pass to a turbine apparatus.
11. A self-cooling, mono-container fuel cell generator apparatus, comprising: a layer of interior insulation; a layer of exterior insulation; a single metal housing having top, bottom and side sections with at least the side section of the housing disposed between the insulation layers, said side section having cooling ducts therein, which ducts in the side section communicate to a source of cooling liquid or gas; a plurality of fuel cells containing electrodes and electrolyte surrounded by the interior insulation; a gaseous oxidant inlet; and a gaseous fuel inlet connected to fuel channels to allow fuel passage to the fuel cells.
12. The self-cooling, mono-container fuel cell generator apparatus of claim 11, where the combination of cooling ducts, interior insulation, and exterior insulation have the ability to control the temperature of the housing below the degradation temperature of the housing metal.
13. The self-cooling, mono-container fuel cell generator apparatus of claim 11, where oxidant channels from the oxidant inlet connect to the cooling ducts to allow gaseous oxidant passage through the cooling ducts to the fuel cells, said gaseous oxidant acting as a cooling gas.
14. The mono-container fuel cell generator apparatus of claim 11, where the housing material is selected from the group of concrete, concrete metal composite, and metal, and the thickness ratio of interior insulation:exterior insulation is from about (1):(.2) to about (1):(3).
15. The self-cooling, mono-container fuel cell generator apparatus of claim 11, also containing means to supply gaseous oxidant to the fuel cells and means to supply gaseous fuel to the fuel cells where at least one of the supply means is effective to provide pressurized gas to the fuel cells.
16. The self-cooling, mono-container fuel cell generator apparatus of claim 11, where the fuel cells are of tubular fuel cell design and the interior insulation is substantially silica-free.
17. The self-cooling, mono-container fuel cell generator apparatus of claim 11, where the fuel cells are of flat plate fuel cell design.
18. The self-cooling, mono-container fuel cell generator apparatus of claim 11, where the fuel cells are of corrugated monolithic design.
19. The self-cooling, mono-container fuel cell generator apparatus of claim 11, having associated with it at least three auxiliaries selected from controls, oxygen or air pre-heater, fuel gas compressor, fuel desulfurizer, oxygen or air compressor, turbine, heat exchanger, and topping combustor.
20. A plurality of the self-cooling, mono-container fuel cell generator apparatus of claim 11, positioned next to each other to provide an array of generators, said array having exterior generator housing side sections and interior generated housing side sections, where the interior housing side sections contain cooling ducts for passage of oxidant to the fuel cells, said passage or oxidant being effective to cool the interior generator housing side sections.
21. A plurality of mono-container fuel cell generator apparatus of claim 20, where a compressor means to pressurize at least one of oxidant and fuel is associated with the fuel cells and the generator apparatus contains hot exit gas means which pass to a turbine apparatus.
22. A plurality of self-cooling, mono-container fuel cell generator apparatus, each generator having: a layer of interior insulation; a layer of exterior insulation; a single metal housing between the insulation layers, the housing containing top, bottom and side sections, the side section of the housing having cooling ducts therein;
a plurality of fuel cells surrounded by the interior insulation; a fuel inlet and fuel transfer channels connecting to the fuel cells; and an oxidant inlet and oxidant transfer channels connecting to the fuel cells; where the plurality of generators are positioned next to each other to provide a close packed array of generators, each generator capable of operating at interior temperatures over about 650°C, said array having exterior generator housing side sections and interior generator housing side sections, and where the interior side sections can be cooled by gas or liquid passing through the cooling ducts at the boundary of the interior side sections of the array.
a plurality of fuel cells surrounded by the interior insulation; a fuel inlet and fuel transfer channels connecting to the fuel cells; and an oxidant inlet and oxidant transfer channels connecting to the fuel cells; where the plurality of generators are positioned next to each other to provide a close packed array of generators, each generator capable of operating at interior temperatures over about 650°C, said array having exterior generator housing side sections and interior generator housing side sections, and where the interior side sections can be cooled by gas or liquid passing through the cooling ducts at the boundary of the interior side sections of the array.
23. The plurality of generator apparatus of claim 22, where the housing material is selected from the group of concrete, concrete metal composite, metal, and ceramic, and the thickness ratio of interior insulation:exterior insulation is from about (1):(.2) to about (1):(3).
24. The plurality of generator apparatus of claim 21, where the combination of cooling ducts, interior insulation, and exterior insulation have the ability to control the temperature of the housing interior side sections below the degradation temperature of the housing metal.
25. The plurality of generator apparatus of claim 22, where oxidant channels from the oxidant inlet connect to the cooling ducts to allow gaseous oxidant passage through the cooling ducts to the fuel cells, said gaseous oxidant acting as a cooling gas.
26. The plurality of generator apparatus of claim 22, also containing means to supply gaseous oxidant to the fuel cells and means to supply gaseous fuel to the fuel cells where at least one of the supply means is effective to provide pressurized gas.
27. The plurality of generator apparatus of claim 22, where the array of generators has associated with it at least three auxiliaries selected from controls, oxygen or air pre-heater, fuel gas compressor, fuel desulfurizer, oxygen or air compressor, turbine, heat exchanger, and topping combustor.
28. The plurality of generator apparatus of claim 22, where a compressor means to pressurize at least one of oxidant and fuel is associated with the array and the array contains hot exit gas means which pass to a turbine apparatus.
Priority Applications (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CZ982702A CZ270298A3 (en) | 1996-12-26 | 1996-12-26 | Self-cooling one package generator from fuel elements and a power unit employing a system of such generators |
EP96945667A EP0894344A1 (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an array of such generators |
HU9902162A HUP9902162A2 (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an array of such generators |
CA002247466A CA2247466A1 (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an array of such generators |
AU16890/97A AU1689097A (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an arr ay of such generators |
PCT/US1996/020749 WO1998029917A1 (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an array of such generators |
CN96180120A CN1209220A (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generator and power plants using an array of such generators |
NO983843A NO983843L (en) | 1996-12-26 | 1998-08-21 | Self-cooled fuel cell generator and power plant with a number of such generators |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA002247466A CA2247466A1 (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an array of such generators |
PCT/US1996/020749 WO1998029917A1 (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an array of such generators |
CN96180120A CN1209220A (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generator and power plants using an array of such generators |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2247466A1 true CA2247466A1 (en) | 1998-07-09 |
Family
ID=27170812
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002247466A Abandoned CA2247466A1 (en) | 1996-12-26 | 1996-12-26 | Self-cooling mono-container fuel cell generators and power plants using an array of such generators |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0894344A1 (en) |
CN (1) | CN1209220A (en) |
AU (1) | AU1689097A (en) |
CA (1) | CA2247466A1 (en) |
HU (1) | HUP9902162A2 (en) |
WO (1) | WO1998029917A1 (en) |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
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EP1429407A1 (en) * | 2002-12-11 | 2004-06-16 | SFC Smart Fuel Cell GmbH | Conception of production series |
US7479342B2 (en) * | 2003-06-18 | 2009-01-20 | Panasonic Corporation | Fuel cell |
KR100880388B1 (en) * | 2005-04-20 | 2009-01-23 | 주식회사 엘지화학 | Housing Member For Battery Module |
JP5082454B2 (en) | 2007-01-16 | 2012-11-28 | トヨタ自動車株式会社 | Fuel cell module for vehicles |
US8497043B2 (en) | 2008-03-26 | 2013-07-30 | Mil3 Inc. | Electrical power generator systems that passively transfer hydrogen and oxygen to fuel cells and methods for generating power via same |
US9297277B2 (en) | 2011-09-30 | 2016-03-29 | General Electric Company | Power plant |
JP6189605B2 (en) * | 2013-02-27 | 2017-08-30 | 京セラ株式会社 | Fuel cell device |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4876163A (en) * | 1987-12-18 | 1989-10-24 | Westinghouse Electric Corp. | Generator configuration for solid oxide fuel cells |
US5573867A (en) * | 1996-01-31 | 1996-11-12 | Westinghouse Electric Corporation | Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant |
-
1996
- 1996-12-26 CN CN96180120A patent/CN1209220A/en active Pending
- 1996-12-26 AU AU16890/97A patent/AU1689097A/en not_active Abandoned
- 1996-12-26 EP EP96945667A patent/EP0894344A1/en not_active Withdrawn
- 1996-12-26 CA CA002247466A patent/CA2247466A1/en not_active Abandoned
- 1996-12-26 HU HU9902162A patent/HUP9902162A2/en unknown
- 1996-12-26 WO PCT/US1996/020749 patent/WO1998029917A1/en not_active Application Discontinuation
Also Published As
Publication number | Publication date |
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WO1998029917A1 (en) | 1998-07-09 |
HUP9902162A2 (en) | 1999-11-29 |
CN1209220A (en) | 1999-02-24 |
EP0894344A1 (en) | 1999-02-03 |
AU1689097A (en) | 1998-07-31 |
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