Flat plate stacked-type fuel reforming apparatus

• US 6,159,434 A
• Filed: 02/10/1998
• Issued: 12/12/2000
• Est. Priority Date: 02/28/1997
• Status: Expired due to Fees

• Current Assignee: Engineering Advancement Association of Japan, Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Satoh, Minoru, Sugimoto, Teruo, Gonjo, Yoshihide
• Primary Examiner(s): TRAN, HIEN THI
• Application Number:
  US09/021,531
• Time in Patent Office: 1,036 Days
• Field of Search: 422/177, 422/191, 422/200, 422/193, 422/195, 422/198, 48/127.7, 48/198.1, 48/198.7, 48/127.9, 252/373, 429/17, 429/19, 429/20, 429/26
• US Class Current: 422/626
• CPC Class Codes: B01J 10/007 in the presence of catalytically active bodies, e.g. porous plates
• CPC Class Codes: B01J 12/007 in the presence of catalytically active bodies, e.g. porous plates
• CPC Class Codes: B01J 19/0093 Microreactors, e.g. miniaturised or microfabricated reactors laboratory containers with capillary fluid transport in microfabricated channels or chambers B01L3/5027
• CPC Class Codes: B01J 19/249 Plate-type reactors
• CPC Class Codes: B01J 2208/00309 with two or more reactions in heat exchange with each other, such as an endothermic reaction in heat exchange with an exothermic reaction
• CPC Class Codes: B01J 2208/0053 Controlling multiple zones along the direction of flow, e.g. pre-heating and after-cooling
• CPC Class Codes: B01J 2219/00783 Laminate assemblies, i.e. the reactor comprising a stack of plates
• CPC Class Codes: B01J 2219/00835 Comprising catalytically active material
• CPC Class Codes: B01J 2219/00873 Heat exchange
• CPC Class Codes: B01J 2219/2453 Plates arranged in parallel
• CPC Class Codes: B01J 2219/2454 Plates arranged concentrically
• CPC Class Codes: B01J 2219/2458 Flat plates, i.e. plates which are not corrugated or otherwise structured, e.g. plates with cylindrical shape
• CPC Class Codes: B01J 2219/2464 Independent temperature control in various sections of the reactor
• CPC Class Codes: B01J 2219/2466 The same reactant stream undergoing different reactions, endothermic or exothermic
• CPC Class Codes: B01J 2219/247 Feeding means for the reactants
• CPC Class Codes: B01J 2219/2474 Mixing means, e.g. fins or baffles attached to the plates
• CPC Class Codes: B01J 2219/2481 Catalysts in granular from between plates
• CPC Class Codes: B01J 2219/2485 Metals or alloys
• CPC Class Codes: B01J 2219/2493 Means for assembling plates together, e.g. sealing means, screws, bolts
• CPC Class Codes: B01J 2219/2496 Means for assembling modules together, e.g. casings, holders, fluidic connectors
• CPC Class Codes: C01B 2203/0233 : the reforming step being a steam reforming step
• CPC Class Codes: C01B 2203/0283 : containing a CO-shift step, i.e. a water gas shift step
• CPC Class Codes: C01B 2203/044 : Selective oxidation of carbon monoxide
• CPC Class Codes: C01B 2203/047 : the impurity being carbon monoxide
• CPC Class Codes: C01B 2203/066 : with fuel cells
• CPC Class Codes: C01B 2203/0811 : by combustion of fuel
• CPC Class Codes: C01B 2203/0822 : the fuel containing hydrogen
• CPC Class Codes: C01B 2203/0838 : by heat exchange with exothermic reactions, other than by combustion of fuel
• CPC Class Codes: C01B 2203/0844 : the non-combustive exothermic reaction being another reforming reaction as defined in groups C01B2203/02 - C01B2203/0294
• CPC Class Codes: C01B 2203/0866 : by combination of different heating methods
• CPC Class Codes: C01B 2203/0883 : by indirect heat exchange
• CPC Class Codes: C01B 2203/1041 : Composition of the catalyst
• CPC Class Codes: C01B 2203/1064 : Platinum group metal catalysts
• CPC Class Codes: C01B 2203/1076 : Copper or zinc-based catalysts
• CPC Class Codes: C01B 2203/1082 : Composition of support materials
• CPC Class Codes: C01B 2203/1223 : Methanol
• CPC Class Codes: C01B 2203/1235 : Hydrocarbons
• CPC Class Codes: C01B 2203/1288 : Evaporation of one or more of the different feed components
• CPC Class Codes: C01B 2203/1294 : Evaporation by heat exchange with hot process stream
• CPC Class Codes: C01B 2203/1614 : Controlling the temperature
• CPC Class Codes: C01B 2203/1695 : Adjusting the feed of the combustion
• CPC Class Codes: C01B 2203/82 : Several process steps of C01B2203/02 - C01B2203/08 integrated into a single apparatus
• CPC Class Codes: C01B 3/323 : Catalytic reaction of gaseous or liquid organic compounds other than hydrocarbons with gasifying agents
• CPC Class Codes: C01B 3/384 : the catalyst being continuously externally heated
• CPC Class Codes: C01B 3/48 : followed by reaction of water vapour with carbon monoxide
• CPC Class Codes: C01B 3/583 : the reaction being the selective oxidation of carbon monoxide
• CPC Class Codes: F28D 9/0093 : Multi-circuit heat-exchangers, e.g. integrating different heat exchange sections in the same unit or heat-exchangers for more than two fluids
• CPC Class Codes: H01M 8/0631 : Reactor construction specially adapted for combination reactor/fuel cell hydrogen C01B3/00; reactors for physicochemical processes B01J19/00
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y02P 20/10 : Process efficiency
• CPC Class Codes: Y02P 20/129 : Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

A fuel reforming apparatus comprising a liquid feed heating portion, an evaporation portion, a steam superheating portion, a reforming portion, a shift reaction portion, a CO oxidization portion, a catalytic combustion portion, and a heat recovery portion. These portions are constituted by flat plates provided with heat-transfer fins in the interior and are stacked into an integral structure, thereby obtaining a temperature distribution along a stacked direction so that the flat plate elements reach a temperature suitable for reforming, combustion, evaporation, shift, and CO oxidization.

Claims

1. A fuel reforming apparatus comprising portions which include:

a liquid feed heating portion for heating liquid feed which comprises water and alcohol or hydrocarbon;

an evaporation portion for evaporating the heated liquid feed to generate feed gases;

a steam superheating portion for superheating the feed gases from an evaporation temperature to a reforming temperature;

a reforming portion for generating hydrogen-rich reformed gases from the superheated feed gases by reforming catalysts;

a catalytic combustion portion for supplying reforming heat to said reforming portion and evaporation heat to said evaporation portion and said steam superheating portion from heat generated by catalytic combustion;

a CO oxidization portion for reducing CO contained in the reformed gases that pass through and emerge from said catalytic combustion portion by catalytic oxidization; and

a heat recovery portion for using exhaust heat from high-temperature combination gases obtained by catalytic combustion as heat sources for said steam superheating portion and said evaporation portion; and

wherein each of said portions are formed of flat plate elements made of a light alloy, the flat plate elements having a manifold for performing intake and exhaust with respect to their periphery and heat-transfer fins in the interior thereof, and said flat plate elements being stacked into an integral construction such that said catalytic combustion portion, reforming portion, steam superheating portion, heat recovery portion, evaporation portion, CO oxidization portion, and liquid feed heating portion are in close proximity to one another from the catalytic combustion portion at a high-temperature side to the liquid feed heating portion at a low-temperature side.

2. The fuel reforming apparatus as set forth in claim 1, wherein said catalytic combustion portion is divided into a plurality of portions and inserted between the reforming portion and the steam superheating portion and wherein a fuel portion of said catalytic combustion portion and the reforming portion are stacked in contact with each other.

3. The fuel reforming apparatus as set forth in claim 1, wherein said heat recovery portion is divided into a plurality of portions and inserted between the evaporation portion and the CO oxidization portion and wherein said heat recovery portion and said evaporation portion are stacked in contact with each other.

4. The fuel reforming apparatus as set forth in claim 1, wherein, when stacking the flat plate elements of said catalytic combustion portion, reforming portion, steam superheating portion, heat recovery portion, evaporation portion, CO oxidation portion and liquid feed heating portion to define a main stacked body, a pair of said reforming portions or a pair of catalytic combustion portions is provided in the center of said main stacked body, wherein said main stacked body comprises first and second identical stacked bodies that are symmetrically stacked about a symmetrical plane.

5. The fuel reforming apparatus as set forth in claim 1, wherein:

said CO oxidization portion and reforming portion each further comprises a flat plate element having heat-transfer fins fixed to the interior, each heat-transfer fin of the CO oxidization portion flat plate element and the reforming portion plate element being filled on the inner side with a CO oxidization catalyst or a reforming catalyst, respectively;

said heat recovery portion and steam superheating portion each further comprises a flat plate element having a combustion gas passage and a steam passage formed with heat-transfer fins alone; and

said flat plate elements are stacked by providing at least one fluid turn-back passage in a stacked direction of said flat plate elements so that fluid turns back at an end of said flat plate element, when said fluid passes the inner side of each heat-transfer fin.

6. The fuel reforming apparatus as set forth in claim 5, wherein said CO oxidization portion comprises flat plate elements provided with one or more turn-back passages, the evaporation portion is provided in contact with the flat plate element of an inlet of said CO oxidization portion into which the reformed gases flow, the liquid feed heating portion is provided in contact with the flat plate element of an outlet of said CO oxidization portion from which the reformed gases flow out, a heat conductor is provided on a boundary surface where the flows of said reformed gases and said liquid feed and steam become opposite flows, and a heat insulator is provided on a boundary surface where the flows of said reformed gases and said liquid feed and steam become parallel flows, thereby obtaining temperature distribution which is high in temperature at the inlet portion and low in temperature at the outlet portion in the stacked direction of said CO oxidization portion and in the directions of said reformed gases and said liquid feed and steam.

7. The fuel reforming apparatus as set forth in claim 5, wherein said CO oxidization portion dispersedly supplies CO oxidization air in correspondence with the CO concentration distribution along a direction of flow in said CO oxidization portion, by alternately stacking a plurality of turn-back passages of reformed-gas chambers and CO oxidization air chambers so that the flows of the reformed gases and the CO oxidization air become parallel flows and also by providing a CO oxidization air dispersion plate with a plurality of dispersion holes between flat plate elements of the reformed-gas chambers and the CO oxidization air chambers so that the air amount distribution in the stacked direction is controlled by the configuration of the dispersion hole and the passage resistance of a fluid passage leading to the dispersion hole.

8. The fuel reforming apparatus as set forth in claim 1, wherein a surface-division heat recovery portion, formed by dividing a surface of the heat recovery portion into an evaporation catalytic combustion portion and a combustion gas heat recovery portion, is provided in close proximity to an upper or lower portion of the evaporation portion and wherein said evaporation catalytic combustion portion and said combustion gas heat recovery portion are alternately disposed on the surface along a flow of steam on the evaporation surface of said evaporation portion.

9. The fuel reforming apparatus as set forth in claim 8, wherein an evaporation temperature corresponding to liquid feed is set by varying the ratio of the areas of the evaporation catalytic combustion portion and the combustion gas heat recovery portion in said surface-division heat recovery portion.

10. The fuel reforming apparatus as set forth in claim 8, wherein:

the evaporation portion is formed by two stages, a liquid feed evaporation portion and a water evaporation portion;

a surface-division heat recovery portion is formed by dividing a surface of the heat recovery portion into an evaporation catalytic combustion portion and a combustion gas heat recovery portion;

said liquid feed evaporation portion and said water evaporation portion are provided in close proximity to said surface-division heat recovery portion, respectively; and

CO oxidization portions are stacked between said liquid feed evaporation portion and said water evaporation portion and outside said liquid feed evaporation portion and said water evaporation portion, respectively.

11. The fuel reforming apparatus as set forth in claim 10, wherein an area ratio of the evaporation catalytic combustion portion to said combustion gas heat recovery portion is reduced at a portion adjacent to the liquid feed evaporation portion where the evaporation temperature is low, and is increased at a portion adjacent to the water evaporation portion where the evaporation temperature is high.

12. A fuel reforming apparatus comprising portions which include:

a liquid feed heating portion for heating liquid feed which comprises water and alcohol or hydrocarbon;

an evaporation portion for evaporating the heated liquid feed to generate feed gases;

a steam superheating portion for superheating the feed gases from an evaporation temperature to a reforming temperature;

a reforming portion for generating hydrogen-rich reformed gases from the superheated feed gases by reforming catalysts;

a catalytic combustion portion for supplying reforming heat to said reforming portion and evaporation heat to said evaporation portion and said steam superheating portion from heat generated by catalytic combustion;

a shift reaction portion for reducing carbon monoxide (CO) contained in the reformed gases generated by said reforming portion;

a CO oxidization portion for reducing the CO contained in the reformed gases emerging from said shift reaction portion by catalytic oxidization; and

a heat recovery portion for using exhaust heat from high-temperature combustion gases obtained by catalytic combustion as heat sources for said steam superheating portion and said evaporation portion; and

wherein each of said portions are formed of flat plate elements made of a light alloy, the flat plate elements having a manifold for performing intake and exhaust with respect to their periphery and heat-transfer fins in the interior thereof, and said flat plate elements being stacked into an integral construction such that said catalytic combustion portion, reforming portion, steam superheating portion, heat recovery portion, shift reaction portion, evaporation portion, CO oxidization portion, and liquid feed heating portion are in close proximity to one another from a high-temperature side to a low-temperature side.

13. The fuel reforming apparatus as set forth in claim 12, wherein said catalytic combustion portion is divided into a plurality of portions and inserted between the shift reaction portion and the evaporation portion and wherein a fuel portion of said catalytic combustion portion and the evaporation portion are stacked in contact with each other.

14. The fuel reforming apparatus as set forth in claim 12, wherein said heat recovery portion is divided into a plurality of portions and inserted between the evaporation portion and said heat recovery portion and wherein said shift reaction portion and said evaporation portion are stacked in contact with each other.