JP2008287972A - Reforming system for fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reforming system for a fuel cell which is advantageous for securing purification capability to purify reforming fluid, even if its useful life becomes long. <P>SOLUTION: The reforming system comprises a reforming part 34, which reforms a reforming material and generates reforming fluid and a purifying part 37 which reduces the load substance contained in the reforming fluid and purifies the reforming fluid. The purifying part 37 can change with the passage of time, by using portions 37f, 37s in the purifying part 37 so that the portion with relatively small deterioration from among the purifying part 37 may be used in the system operation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel cell reforming system that generates reformed gas containing hydrogen by reforming a reforming raw material.

  Generally, a reforming system includes a reforming unit that generates reformed gas with reforming fuel and steam, an evaporation unit that generates water vapor by heating water and supplies the reformed unit, and a reforming unit. And a carbon monoxide purification unit for reducing carbon monoxide contained in the reformed gas flowing out from the mass part. Patent Document 1 discloses a fuel cell assembly in which a reforming case and a stack cell are provided in and removed from a rectangular parallelepiped housing. According to this, when it is necessary to replace the catalyst in the reforming case with the power generation operation, the front wall or the rear wall of the rectangular parallelepiped housing of the fuel cell assembly is opened, and the reforming case Is removed from the housing, the catalyst in the reforming case is replaced with a new one, and then the power generation unit is loaded into the housing of the fuel cell assembly. Furthermore, when it becomes necessary to replace the stack cell, the front wall or the rear wall of the fuel cell assembly housing is opened, the stack cell is removed from the housing, and the stack cell is replaced with a new one. The stack cell is then loaded into the housing of the fuel cell assembly.

Patent Document 2 discloses a technique for knowing the deterioration characteristics and operation time of a fuel cell, thereby predicting a decrease in efficiency performance of the fuel cell device, and accurately grasping maintenance information for replacing the fuel cell. Yes.
Japanese Patent Laying-Open No. 2005-93081 JP 2004-21433 A

  In the industry, even if the service life is prolonged, it is desired to further reduce the load substances such as carbon monoxide contained in the reforming fluid such as the reformed gas generated in the reforming section.

  The present invention has been made in view of the above circumstances, and even if the service life is prolonged, the fuel cell reforming system is advantageous to ensure the purifying ability to purify reformed fluid such as reformed gas. It is an issue to provide.

(1) A reforming system for a fuel cell according to aspect 1 includes a reforming unit that reforms a reforming raw material to generate a reforming fluid, and a load substance contained in the reforming fluid is reduced and modified. A reforming system for a fuel cell comprising a purifying section for purifying a fluid,
The purification unit is characterized in that the use part in the purification part can be switched over time so that the part of the purification part that is relatively less deteriorated is used during system operation. In this case, a portion of the purification unit that is relatively less deteriorated is used during system operation. For this reason, even if the service life is prolonged, the purifying ability to purify the reforming fluid such as the reformed gas is ensured. It is preferable that two or more use parts are provided.

  (2) According to the reforming system for a fuel cell according to aspect 2, in the above aspect, regular or irregular maintenance is performed so that a portion of the purification unit that is relatively less deteriorated is used during system operation. In this case, the use site in the purification unit can be switched over time. In this case, a portion of the purification unit that is relatively less deteriorated is switched during maintenance and used during system operation. For this reason, even if the service life is prolonged, the purification ability for purifying the reformed fluid is ensured.

  (3) According to the fuel cell reforming system according to aspect 3, in the above aspect, the part of the purification unit that has deteriorated is replaced during regular or irregular maintenance. And In this case, the part of the purifier that has deteriorated is replaced during maintenance. Accordingly, a portion of the purification unit that is relatively less deteriorated is used during system operation. For this reason, even if the service life is prolonged, the purification ability for purifying the reformed fluid is ensured.

  (4) According to the fuel cell reforming system according to aspect 4, in the above aspect, the part of the purification unit that has deteriorated due to the system operation is a part of the purification unit that is less deteriorated in the normal operation of the system. It is switched, and the part where the deterioration has progressed in the purifying part can be replaced during regular or irregular maintenance. In this case, since the portion of the purification unit that is relatively less deteriorated is used during system operation, even if the service life is prolonged, the purification ability to purify the reformed fluid is ensured.

  (5) According to the reforming system for a fuel cell according to aspect 5, in the above aspect, the purification unit is formed of a divided purification unit divided into a plurality of parts, and the divided purification unit with relatively little deterioration is provided. The divided purification unit is characterized in that it can be switched over time so as to be used during operation. In this case, among the plurality of divided purification units constituting the purification unit, the divided purification unit that is relatively less deteriorated is used during system operation. Therefore, even if the service life is prolonged, the purification that purifies the reformed fluid. Performance is ensured.

  (6) According to the reforming system for a fuel cell according to aspect 6, in each of the above aspects, each split purification unit includes an inflow part to which an inflow pipe for allowing the reformed fluid to flow is detachably mounted, and reduces load substances. And an outflow portion to which an outflow pipe for allowing the purified reformed fluid to flow out is detachably mounted. In this case, if an inflow pipe and an outflow pipe are attached to each divided purification section, a load substance such as carbon monoxide can be purified by the divided purification section. In addition, it is preferable that the cover part which closes the inflow part and outflow part of the division | segmentation purification part which is not used is provided.

  (7) According to the reforming system for a fuel cell according to aspect 7, in the above aspect, each of the divided purification units is arranged along the circumferential direction of the concentric axis. Any of a plurality of division purification units can be used. Furthermore, regardless of which of the plurality of divided purification sections is used, variation in the heat receiving balance received from the reforming section is easily reduced, and variation in purification performance in each divided purification section is reduced.

  (8) According to the reforming system for a fuel cell according to aspect 8, in the above aspect, each of the divided purification units is arranged along the axial length direction of the concentric axis. Any of a plurality of division purification units can be used.

  (9) According to the fuel cell reforming system according to aspect 9, in the above aspect, the capacity of the split purification unit used at the end of the useful life of the system is divided purification used at the beginning of the service life of the system. It is characterized by being set larger than the capacity of the part. If the system is used for a long period of time, the catalyst or membrane in the membrane electrode assembly of the fuel cell may deteriorate, and the power generation output, particularly the voltage, may decrease. Therefore, in order to maintain the power generation capability of the fuel cell, an operation of increasing the generated current value by increasing the flow rate per unit time of the reforming fluid sent to the fuel electrode of the fuel cell compared to the initial time may be performed. is there. In this case, it is preferable to increase the purification flow rate of the reforming fluid in the split purification unit used at the end of the service life. Therefore, it is preferable to increase the capacity of the split purification unit used at the end of the service life, rather than the capacity of the split purification unit used at the beginning of the service life.

  (10) According to the fuel cell reforming system according to aspect 9, in the above aspect, the catalyst in each split purification unit is the same system, and the catalyst amount in the split purification unit used at the end of the service life of the system is The amount of catalyst is set to be larger than the amount of catalyst in the division purification unit used at the beginning of the service life of the system. If the system is used for a long period of time, the catalyst or membrane in the membrane electrode assembly of the fuel cell may deteriorate, and the power generation output, particularly the voltage, may decrease. Therefore, in order to maintain the power generation capacity of the fuel cell, at the end of the service life, the flow rate per unit time of the reforming fluid sent to the fuel electrode of the fuel cell is increased compared to the initial life of the fuel cell, and the generated current value An operation to increase the In this case, it is preferable to increase the catalyst amount in the split purification unit used at the end of the service life, compared to the catalyst amount in the split purification unit used in the initial period of the service life. Thereby, the fall of power generation output is controlled.

  (11) According to the fuel cell reforming system according to aspect 10, in the above aspect, the reforming unit reforms the reforming raw material to generate reformed gas, and the purification unit modifies the reforming material. It is characterized by purifying the reformed gas by reducing carbon monoxide contained in the quality gas. Examples of the purification unit include a form in which the reformed gas is purified by reducing carbon monoxide by an oxidation reaction, and a form in which the reformed gas is purified by reducing carbon monoxide by a methanation reaction.

  According to the present invention, it is possible to provide a reforming system for a fuel cell that is advantageous for securing a purifying ability for purifying a reforming fluid even if the service life is prolonged.

  In the reforming system for a fuel cell according to the present invention, the reforming unit reforms the reforming raw material to generate a reforming fluid. The reforming raw material may be gaseous, liquid, or solid. The purification unit purifies the reformed fluid by reducing the load substance contained in the reformed fluid. An example of the load substance is carbon monoxide.

  Embodiment 1 of the present invention will be specifically described below with reference to FIGS. The reforming system according to this embodiment is applied to a fuel cell system.

(overall structure)
FIG. 1 shows a conceptual diagram of the system. In FIG. 1, most of the hatching is omitted to avoid complication. As shown in FIG. 1, the fuel cell 1 is formed by assembling a plurality of membrane electrode assemblies 13 that sandwich a solid polymer membrane 10 having proton conductivity between a fuel electrode 11 and an oxidant electrode 12 in the thickness direction. Yes. Examples of the material of the solid polymer film 10 include a fluorocarbon resin (for example, perfluorosulfonic acid resin) or a hydrocarbon resin. The fuel cell 1 may be a system in which a plurality of sheet-like membrane electrode assemblies 13 are stacked in the thickness direction, or a system in which a plurality of tube-shaped membrane electrode assemblies 13 are arranged.

  The reformer 2 includes a combustion unit 30 that functions as a heating unit formed by a combustion burner, a reforming unit 34 that is heated by the combustion unit 30, an evaporation unit 36, and a purification unit (carbon monoxide reduction unit) 37. And have. The reforming section 34 has a cylindrical shape having a central axis along the vertical direction, and reforming fuel (reforming raw material) is reformed with steam (the following formula (1)) to reform gas. And has a catalyst 34e. The reforming unit 34 faces the combustion passage 32 that faces the combustion unit 30. A combustion passage 33 is formed coaxially so as to surround the reforming portion 34. A cylindrical heat insulating portion 31 is formed coaxially. Further, on the outer peripheral side of the reforming part 34, an evaporation part 36 for evaporating the raw material water is formed coaxially. A purification unit 37 (carbon monoxide reduction unit) is coaxially formed around the evaporation unit 36.

  As shown in FIG. 1, a combustion passage 35 is formed coaxially on the outer peripheral side of the heat insulating portion 31. Combustion gas burned in the combustion burner flows in the order of the combustion passage 32, the combustion passage 33, and the combustion passage 35. The evaporator 36 is heated by the combustion gas flowing through the combustion passage 35. A cylindrical purification part 37 is arranged in an adjacent state so as to surround the evaporation part 36. For this reason, the evaporator 36 and the purifier 37 exchange heat with each other. During the operation of the reforming apparatus 2, the purification unit 37 generally gives heat to the evaporation unit 36 because the temperature of the purification unit 37 is higher than the temperature of the evaporation unit 36 at which liquid phase water evaporates. The outer peripheral portion of the purifying portion 37 is covered with a cylindrical heat insulating material 39 having high heat insulating properties so as to surround and retain the heat.

  Further, as shown in FIG. 1, the reformer 2 includes a heat exchange unit 4 disposed below the reforming unit 34, a CO shift unit 5 disposed below the heat exchange unit 4, and a CO shift unit. 5 and a heat exchanger 47 having an electric heater disposed between the heat exchanger 4 and the heat exchanger 4. Here, the heat exchange unit 4 is provided downstream of the evaporation unit 36, and the CO shift unit 5 is provided downstream of the heat exchange unit 4.

  The CO shift unit 5 promotes a shift reaction using water vapor based on the following formula (2), and reduces CO contained in the reformed gas. The CO shift unit 5 has a passage 5i, a passage 5v, and a turning portion 5m. The outlet 5p of the CO shift unit 5 and the oxidation air passage 75 are connected by a purification passage 400 via the second merge region M2.

  The purification unit 37 is disposed downstream of the CO shift unit 5 and oxidizes and reduces CO contained in the reformed gas purified by the CO shift unit 5 based on the following equation (3). It promotes the oxidation reaction. According to the present embodiment, the CO shift unit 5 becomes hydrogen-rich during the operation of the reformer 2 and becomes a reducing condition. For this reason, if the catalyst 5e of the CO shift unit 5 is only slightly oxidized, the catalyst 5e is easily reduced during operation of the reformer.

However, the catalyst of the purification unit 37 is not easily reduced only during operation of the reformer. In a state where oxygen is supplied to the purification unit 37, there is an active temperature range (for example, 100 to 200 ° C.) of the catalyst of the purification unit 37. When this temperature is exceeded, it is said that it is preferable not to exceed 200 ° C. because the catalyst of the purification unit 37 tends to deteriorate in an oxidizing atmosphere. Considering this, the purifying unit 37 is actively cooled by the evaporation unit 36 from which the heat of vaporization is removed.
Formula (1) ... CH ₄ + H ₂ O → 3H ₂ + CO
Formula (2) ... CO + H ₂ O → H ₂ + CO ₂
Formula (3) ... CO + 1 / 2O ₂ → CO ₂
Next, the passage system will be further described. As shown in FIG. 1, a fuel passage 62 connected to the fuel supply source 61 through a valve 25a is provided. The fuel of the fuel supply source 61 may be gaseous fuel, liquid fuel, or pulverized fuel. Specifically, hydrocarbon fuel and alcohol fuel are exemplified. For example, city gas, LPG, kerosene, methanol, dimethyl ether, gasoline, biogas and the like are exemplified. The fuel passage 62 includes a combustion fuel passage 62a connected to the combustion section 30 via the valve 25a and the pump 27a, and a reforming fuel connected to the inlet 4i of the heat exchange section 4 via the pump 27b, the desulfurizer 62x and the valve 25b. And a passage 62c (reforming fuel supply unit). An air passage 72 (oxygen supply unit) connected to the air supply source 71 is provided. The air passage 72 includes a combustion air passage 73 connected to the combustion unit 30 through the pump 27c, and an oxidation air passage 75 (oxygen) connected to the inlet 37i of the purification unit 37 through the air purification filter 72x, the pump 27d, and the valve 25d. Supply section).

  As shown in FIG. 1, a reforming water passage 82 (water supply unit) that connects the water tank 81 and the inlet 36i of the evaporation unit 36 via a pump 27m and a valve 25m is provided. An anode gas passage 100 (reformed gas discharge passage) that connects the outlet 37p of the purification unit 37 and the inlet 11i of the fuel electrode 11 of the fuel cell 1 via a valve 25e (outlet valve) is provided. The outlet 37p of the purification unit 37 is formed on the upper side of the purification unit 37 in the height direction. An off-gas passage 110 is provided that connects the outlet 11p of the fuel electrode 11 of the fuel cell 1 and the combustion unit 30 via a valve 25f. The off gas passage 110 discharges the anode off gas after the power generation reaction. A bypass passage 150 that connects the off gas passage 110 and the anode gas passage 100 via a valve 25h (outlet valve) is provided.

  As shown in FIG. 1, a cathode gas passage 200 communicating with the air supply source 71 and the inlet 12i of the oxidant electrode 12 of the fuel cell 1 via a pump 27k and a valve 25k is provided. As shown in FIG. 1, a combustion exhaust gas passage 250 is provided for releasing the combustion exhaust gas combusted in the reforming section 34 to the outside. A steam passage 300 is provided that connects the outlet 36p of the evaporation section 36 of the reformer 2 and the reforming fuel passage 62c via the first merge region M1. The upper end portion 300 e of the water vapor passage 300 is connected to the outlet 36 p of the evaporation portion 36. The lower end portion 300f of the water vapor passage 300 is connected to the merge area M1. The pumps 27a, 27b, 27c, 27d, 27k, and 27m function as fluid conveying elements.

  As shown in FIG. 1, the outlet 5 p of the CO shift unit 5 and the inlet 37 i of the purification unit 37 are connected by a purification passage 400. The reformed gas (hydrogen is a main component and contains carbon monoxide) discharged from the outlet 5p of the CO shift unit 5 flows upward in the purification passage 400 in the direction of the arrow W2, and passes through the second merge region M2 to obtain the purification unit. 37 to the inlet 37i. The inlet 37 i is formed on the lower side of the purification unit 37 in the height direction.

  Next, when the reforming apparatus 2 is started will be described with reference to FIG. In this case, combustion air is supplied to the combustion unit 30 via the combustion air passage 73 by the pump 27c. Further, gaseous combustion fuel (combustible fuel) is supplied to the combustion unit 30 through the combustion fuel passage 62a by the valve 25a and the pump 27a. As a result, the combustion section 30 is ignited and heated, and as a result, the reforming section 34 is heated so as to be suitable for the reforming reaction. The evaporating unit 36 and the purifying unit 37 together with the reforming unit 34 are also heated to a high temperature.

  Thereafter, the reforming water (water before the reforming reaction) is supplied from the water tank 81 and the reforming water passage 82 to the inlet 36i of the evaporator 36 through the pump 27m and the valve 25m. The reformed water is steamed in the high temperature evaporator 36 of the reformer 2. The generated water vapor reaches the first merge region M1 through the water vapor passage 300 from the outlet 36p of the evaporation section 36. On the other hand, the reforming fuel is supplied to the inlet 4i of the heat exchanging unit 4 through the desulfurizer 62x, the reforming fuel passage 62c, and the first merge region M1 by the valve 25a, the pump 27b, and the valve 25b. In the first merge region M1, the reforming fuel in the reforming fuel passage 62c and the steam in the steam passage 300 are merged and mixed. The merged mixed fluid is supplied to the inlet 4 i of the heat exchange unit 4.

  The mixed fluid passes through the first passage 4 a on the low temperature side of the heat exchange unit 4. At this time, heat exchange is performed with the high-temperature reformed gas flowing through the second passage 4c on the high temperature side of the heat exchange unit 4. For this reason, the mixed fluid before the reforming reaction is heated. The mixed fluid flows into the outer passage 34p of the reforming portion 34, flows in the direction of arrow A1, flows into the inner passage 34i through the turn-up portion 34m, and flows in the direction of arrow A2. At this time, the mixed fluid in which the steam (or condensed water) and the reforming fuel are mixed becomes a hydrogen-rich (40 mol% or more) reformed gas by the reforming reaction shown in (1). This reformed gas contains carbon monoxide.

  Further, the high-temperature reformed gas that has undergone the reforming reaction flows from the reforming section 34 into the heat exchanging section 4. That is, the high-temperature reformed gas passes through the second passage 4c on the high temperature side of the heat exchange unit 4 from the reforming unit 34, thereby heating the mixed fluid in the first passage 4a on the low temperature side. Further, the reformed gas flows into the CO shift unit 5 from the inlet 5 i of the CO shift unit 5 through the warm-up unit 47. In the CO shift unit 5, a shift reaction using water vapor is performed as shown in the above formula (2). As a result, carbon monoxide contained in the reformed gas is reduced, and the reformed gas is purified.

Further, the reformed gas purified in the CO shift unit 5 flows from the outlet 5p of the CO shift unit 5 through the purification passage 400 in the direction of the arrow W2 and reaches the second merge region M2. Further, the reformed gas joins the oxidizing air (oxygen component, selective oxidizing air used for the selective reaction in the purifying unit 37) in the oxidizing air passage 75 (oxygen supply unit) in the second merging zone M2. The combined reformed gas flows into the purification unit 37 from an inlet 37 i formed at the lower part of the purification unit 37. In the purification unit 37, as shown in the above-described formula (3), an oxidation reaction (CO + 1 / 2O ₂ → CO ₂ ) using oxygen is performed. As a result, CO contained in the reformed gas is purified and further reduced.

  The reformed gas thus purified is supplied as an anode gas from the outlet 37p of the purification unit 37 to the inlet 11i of the fuel electrode 11 of the fuel cell 1 through the anode gas passage 100 and the valve 25e. The air functioning as the cathode gas is supplied to the inlet 12i of the oxidant electrode 12 of the fuel cell 1 through the cathode gas passage 200 by the pump 27k and the valve 25k. As a result, a power generation reaction occurs in the fuel cell 1 and electric energy is generated. The off gas after the power generation reaction of the anode gas (the gas discharged from the fuel cell 1) may contain hydrogen that has not undergone the power generation reaction. For this reason, the off-gas is supplied to the combustion unit 30 through the off-gas passage 110 and burned, and becomes a heat source for the combustion unit 30.

  As shown in FIG. 1, a CO shift unit temperature detector 55 that detects a temperature T11 on the upstream side (inlet side of the passage 5i) of the CO shift unit 5 is provided. A CO shift portion temperature detector 39 for detecting a temperature T31 in the vicinity of the turning portion 5m of the CO shift portion 5 is provided. A CO reduction unit temperature detector 38 for detecting the upstream temperature T12 of the purification unit 37 is provided. Further, a reforming unit temperature detector 31t for detecting the temperature T1 on the outlet side of the reforming unit 34 is provided. A temperature detector 65 that detects the temperature T2 of the first merge region M1 where the steam and the reforming fuel merge is provided. Each detection signal is input to the control device 500.

(Main part configuration)
Now, the main part of the present embodiment will be described with reference to FIG. FIG. 2 shows a main configuration of the reforming system. In order to avoid complication of the drawing, some hatching is omitted. As shown in FIG. 2, the purification unit 37 includes an upper first divided purification unit 37f and a lower first division unit 37f divided into a plurality along the axial length direction (vertical direction) of the central axis P1 that is a concentric circular axis. It is formed by a two-part purification unit 37s. According to the present embodiment, the first divided purification unit 37f and the second divided purification unit 37s are disposed substantially coaxially with respect to the central axis P1, are independent of each other, and are not in communication with each other. . The first divided purification unit 37f and the second divided purification unit 37s are used over time so that one of the first divided purification unit 37f and the second divided purification unit 37s with relatively little deterioration is used during system operation. Can be switched to each other. The first divided purification unit 37f and the second divided purification unit 37s basically have substantially the same configuration, substantially the same operation effect, substantially the same capacity, and almost the same purification ability, and therefore the first division purification unit 37f. And description of the second divided purification unit 37s is omitted.

As shown in FIG. 2, the first division purification unit 37 f is disposed outside the wall body 36 k that partitions the evaporation unit 36, and includes a metal or ceramic casing 370 and monoxide contained in the reformed gas. And a catalyst carrier portion 371 that reduces carbon by a CO reduction reaction (selective oxidation reaction, methanation reaction). In the purification unit 37, the upstream 37u is close to the inlet 37i to which the oxidizing air is supplied, so that the oxygen concentration is relatively high. On the other hand, the downstream 37d is far from the inlet 37i and has a relatively lower oxygen concentration than the upstream 37u. Therefore, in the upstream 37u, a selective oxidation reaction (exothermic reaction) in which oxygen is consumed is likely to occur, and the reaction activation temperature is generally 100 to 200 ° C. On the other hand, in the downstream 37d on the side where oxygen is consumed, a methanation reaction (exothermic reaction) purified by hydrogen is more likely to occur than a selective oxidation reaction purified by oxygen. The methanation reaction is also a carbon monoxide reduction reaction, similar to the selective oxidation reaction.
Selective oxidation reaction: CO + 1 / 2O ₂ → CO ₂
Methanation reaction: CO + 3H ₂ → CH ₄ + H ₂ O
Since the evaporation unit 36 vaporizes water, the operation temperature of the evaporation unit 36 is affected by the heat of vaporization of water, and is lower than the temperature of the purification unit 37 and is about 100 ° C. That is, the evaporation part 36 tends to be relatively low temperature due to the influence of the heat of vaporization of water.

  As shown in FIG. 2, the first split purification unit 37f includes an inflow part 81 into which an inflow pipe 75M (corresponding to the purification passage 400) through which the reformed gas flows is detachably attached, and carbon monoxide (load substance). ) In which the outflow piping 100M (corresponding to the anode gas passage 100) for flowing out the reformed gas after purification is detachably mounted, and the inflow portion 81 of the divided purification portion 37f that is not used, and And a lid 83 that closes the outflow portion 82.

  Similarly, the second divided purification unit 37s is provided with an inflow part 81 in which an inflow pipe 75M through which the reformed gas is introduced is detachably attached, and the purified gas after purification with reduced carbon monoxide (load substance). An outflow portion 82 to which the outflow piping 100M to be discharged is detachably attached, and an inflow portion 81 of the divided purification portion 37s that is not used and a lid portion 83 that closes the outflow portion 82 are provided.

  According to the present embodiment, among the first divided purification unit 37f and the second divided purification unit 37s, the first divided purification unit 37f is used in the first half period (initial stage) of the service life, and the second divided purification unit 37s Not used. In this case, when the system is stopped, the connector 75N of the inflow pipe 75M is connected to the inflow part 81 of the first split purification unit 37f, and the connector 100N of the outflow pipe 100M is connected to the outflow part of the first split purification unit 37f. 82. In this case, with respect to the second divided purification unit 37s that is not used, the lid 83 is attached to the inflow portion 81 and the outflow portion 82, and the second divided purification unit 37s is closed in a sealed state and is kept on standby.

  The inflow portion 81 and the outflow portion 82 in the second divided purification portion 37s are closed by attaching the lid portion 83, but the present invention is not limited thereto, and the connector 75N of the inflow piping 75M and the connector 100N of the outflow piping 100M are connected. If it removes, the inflow part 81 and the outflow part 82 are good also as a seal structure sealed automatically by the cover part incorporated in these.

  By the way, there is a possibility that the catalyst supported on the catalyst carrier portion 371 of the second divided purification unit 37s may be oxidized during the standby of the second divided purification unit 37s. However, when the second split purification unit 37s is used, the reformed gas supplied to the second split purification unit 37s contains hydrogen as a main component, so that the catalyst is quickly reduced. Thus, when the 1st division | segmentation purification | cleaning part 37f is used, the 2nd division | segmentation purification | cleaning part 37s is not used, but the 2nd division | segmentation purification | cleaning part 37s is adjacent to the evaporation part 36 maintained at about 100 degreeC. Yes. For this reason, overheating of the second divided purification unit 37s is suppressed, and deterioration of the second divided purification unit 37s is suppressed. In particular, the water in the evaporating section 36 flows upward (in the direction of the arrow U1) and faces the second divided purification section 37s and the first divided purification section 37f in this order. For this reason, since the water which faces the 2nd division | segmentation purification | cleaning part 37s is comparatively low temperature, it is effective in the overheating prevention of the 2nd division | segmentation purification | cleaning part 37s in standby.

  On the other hand, in the second half period (end) of the service life, the second divided purification unit 37s is used, and the first divided purification unit 37f is not used. In this case, the inflow piping 75M is connected to the inflow portion 81 of the second divided purification portion 37s, and the outflow piping 100M is connected to the outflow portion 82 of the second divided purification portion 37s. In this case, a lid portion 83 is attached to the inflow portion 81 and the outflow portion 82 of the first divided purification portion 37f and closed in a sealed state.

  If the service life of the reforming system is, for example, 10 years, for example, in the first to fifth years, the first divided purification unit 37f is used, and the second divided purification unit 37s is not used. For example, in the sixth to tenth years, the second divided purification unit 37s is used, and the first divided purification unit 37f is not used. If the service life is 15 years, for example, in the 10th to 15th years, the first divided purification unit 37f is used again. In this case, it is preferable to replace the catalyst carrier part 371 of the first divided purification part 37f in advance.

  As described above, according to the present embodiment, the portion of the first divided purification unit 37f and the second divided purification unit 37s that has relatively little deterioration is used during system operation. For this reason, even if the service life is prolonged, the purification ability for purifying the reformed gas is ensured. According to the present embodiment, during regular or irregular maintenance, the maintenance contractor or user can select the catalyst carrier portion 371 at the site where deterioration has progressed in the first divided purification unit 37f and the second divided purification unit 37s. Can be exchanged for a new one. The control device 500 has a timer function, and the timing of switching from the first divided purification unit 37f to the second divided purification unit 37s based on the cumulative operation time, and counting means 500a that counts the cumulative operation time of the reforming system. If it arrives, it can have the notification means 500c which notifies a maintenance contractor or a user visually or audibly. According to the present embodiment, the capacity of the first divided purification unit 37f used in the first half of the useful life and the capacity of the second divided purification unit 37s used in the second half of the useful life are basically the same. Are the same. The catalyst amount of the first divided purification unit 37f and the catalyst amount of the second divided purification unit 37s are basically the same. Both catalysts are syngeneic. This is to suppress fluctuations in the performance of the reforming system when the use of the first divided purification unit 37f and the second divided purification unit 37s is switched.

  Embodiment 2 of the present invention will be described below. Since this embodiment basically has the same configuration and the same operation and effect as those of the first embodiment, FIGS. 1 and 2 are applied correspondingly. Hereinafter, a description will be given centering on portions different from the first embodiment. The first divided purification unit 37f and the second divided purification unit 37s basically have the same configuration and the same operation and effect, but are larger than the capacity of the first divided purification unit 37f used in the first half of the service life. The capacity of the second divided purification unit 37s used in the latter half of the useful life is increased by a predetermined amount (for example, 1.5 to 30%).

  The reason is as follows. If the period of use of the reforming unit 34 becomes long, the catalyst or the like in the membrane electrode assembly of the solid polymer fuel cell may be deteriorated. Therefore, in order to maintain the power generation capacity of the fuel cell, control may be performed to increase the flow rate of reformed gas per unit time at the fuel electrode of the fuel cell by a predetermined amount compared to the first half of the service life. In this case, it is preferable to increase the purification gas purification flow rate in the second divided purification unit 37s used in the latter half of the service life. Therefore, the capacity of the second divided purification unit 37s used in the latter half of the service life is increased more than the capacity of the first divided purification unit 37f used in the first half period. If the type of the catalyst of the second divided purification unit 37s and the type of the catalyst of the first divided purification unit 37f are the same, the catalyst amount of the second divided purification unit 37s used in the latter half of the service life is set to the first half of the service life. The catalyst amount of the first divided purification unit 37f used in the period is increased.

  In the above case, the flow rate of the reformed gas supplied to the second split purification unit 37s used in the second half period is higher than the flow rate of the reformed gas supplied to the first split purification unit 37f used in the first half period. Will be increased. Therefore, the flow rate of the oxidizing air supplied to the second divided purification unit 37s used in the second half of the service life is the oxidizing air supplied to the first divided purification unit 37f used in the first half of the service life. The flow rate is increased. Accordingly, the amount of heat generated in the second divided purification unit 37s used in the second half period tends to be larger than the amount of heat generated in the first divided purification unit 37f used in the first half period. In this regard, according to the present embodiment, the raw material water flows upward (in the direction of the arrow U1) in the evaporation unit 36 and faces the upper first divided purification unit 37f next to the lower second divided purification unit 37s. . That is, the cold raw water faces the second divided purification unit 37s, which tends to increase the calorific value, at an early stage. For this reason, it is effective in preventing overheating of the second divided purification unit 37s, which tends to increase the amount of heat generation. In the evaporation unit 36, the raw water may be faced in the order of the second divided purification unit 37s after the first divided purification unit 37f.

  Embodiment 3 of the present invention will be described below. Since this embodiment basically has the same configuration and the same operation and effect as those of the first embodiment, FIGS. 1 and 2 are applied correspondingly. Hereinafter, a description will be given centering on portions different from the first embodiment. Of the first divided purification unit 37f and the second divided purification unit 37s constituting the purification unit 37, the side on which the deterioration has progressed due to the system operation is switched to the side with less deterioration during the normal operation of the system. During regular or irregular maintenance, the catalyst carrier on the deterioration side of the first divided purification unit 37f and the second divided purification unit 37s can be replaced. In this case, since a portion with relatively little deterioration is used during system operation, even if the service life is prolonged, the purification ability for purifying the reformed gas is ensured.

  3 and 4 show a fourth embodiment of the present invention. The present embodiment basically has the same configuration and the same function and effect as the first embodiment. Hereinafter, the description will focus on the different parts. As shown in FIG. 4, the purification unit 37C is substantially equally divided into four along the circumferential direction around the central axis P1 (concentric circular axis). The first division purification unit 37f and the second division A purification unit 37s, a third divided purification unit 37t, and a fourth divided purification unit 37h are provided. As the system usage period becomes longer, the first divided purification unit 37f, the second divided purification unit 37s, the third divided purification unit 37t, and the fourth divided purification unit 37h are used in this order.

  The first split purification unit 37f includes an inflow part 81 to which a connector 75N of an inflow pipe 75M through which the reformed gas flows is detachably attached, and the purified gas after purification with reduced carbon monoxide (load substance). An outflow portion 82 to which the connector 100N of the outflow piping 100M to be outflowed is detachably mounted, and an inflow portion 81 of the unused divided purification portion 37f and a lid portion 83 for closing the outflow portion 82 are provided. The same applies to the second divided purification unit 37s, the third divided purification unit 37t, and the fourth divided purification unit 37h. The lid portion may be built in the inflow portion 81 and the outflow portion 82 so that it can be automatically closed.

  Of the first divided purification unit 37f to the fourth divided purification unit 37h, the connector 75N of the inflow pipe 75M is connected to the inflow part 81, and the connector 100N of the outflow pipe 100M is connected to the outflow part 82. A closing lid 83 is attached to the inflow portion 81 and the outflow portion 82 of the first divided purification portion 37f to the fourth divided purification portion 37h that are not used.

  As described above, according to the present embodiment, among the first divided purification unit 37f to the fourth divided purification unit 37h, a portion with relatively little deterioration is used during system operation. For this reason, even if the service life is prolonged, the purification ability for purifying the reformed gas is ensured. Since the first divided purification unit 37f to the fourth divided purification unit 37h are equally divided around the central axis P1 and are set at the same height position with respect to the central axis P1, the first divided purification is performed. Regardless of which of the part 37f to the fourth divided purification part 37h is used, if the first divided purification part 37f to the fourth divided purification part 37h are basically the same size and amount, the reforming part 34 The variation in heat receiving balance received from the steel is easily reduced. Furthermore, the variation of the heat balance with respect to the evaporation part 36 is easy to be reduced. Therefore, the variation in the purification ability of the first divided purification unit 37f to the fourth divided purification unit 37h is likely to be reduced.

  According to the present embodiment, the first divided purification unit 37f to the fourth divided purification unit 37h may have an open / close lid (not shown). In this case, during regular or irregular maintenance, the maintenance contractor or the user opens the opening / closing lid, and the catalyst in the portion where deterioration has progressed among the first divided purification unit 37f to the fourth divided purification unit 37h. The carrier part 371 can be replaced with a new catalyst carrier part 371. According to the present embodiment, the capacity and the amount of catalyst are basically the same for the first divided purification unit 37f to the fourth divided purification unit 37h.

  Further, among the first divided purification unit 37fC to the fourth divided purification unit 37h, the capacity and the amount of catalyst used in the latter half of the service life are increased more than the capacity and the amount of catalyst used in the first half. be able to. That is, the capacity is increased by a predetermined percentage as the process proceeds to the first divided purification unit 37f, the second divided purification unit 37s, the third divided purification unit 37t, and the fourth divided purification unit 37h (in order of use). Also good. Further, the catalyst amount may be increased by a predetermined percentage. The purifying portion 37C is divided into four parts around the central axis P1 (concentric circular axis), but is not limited to this, and the purification part 37C is divided almost equally into two, three, five, or six. Also good.

  FIG. 5 shows a fifth embodiment of the present invention. The present embodiment basically has the same configuration and the same function and effect as the first embodiment. Hereinafter, the description will focus on the different parts. As shown in FIG. 5, the purification unit 37D includes a first divided purification unit 37f and a second divided purification unit 37s arranged along the axial direction of the central axis P1 (concentric circular axis). Of the first divided purification unit 37f and the second divided purification unit 37s, the upper first divided purification unit 37f is used and the second divided purification unit 37s is not used in the first half period (initial stage) of the service life. For this reason, the connector 75N of the inflow piping 75M is detachably connected to the inflow portion 81 of the first divided purification portion 37f. The connector 100N of the outflow pipe 100M is detachably connected to the outflow part 82 of the first split purification unit 37f. In this case, about the 2nd division | segmentation purification | cleaning part 37s which are not used, the cover part 83 for closure is attached to the inflow part 81 and the outflow part 82, and is closed.

  On the other hand, in the second half of the useful life (end), the lower second divided purification unit 37s is used, and the first divided purification unit 37f is not used. For this reason, the connector 75N of the inflow piping 75M is detachably connected to the inflow portion 81 of the second divided purification portion 37s. The connector 100N of the outflow pipe 100M is detachably connected to the outflow part 82 of the second divided purification unit 37s. In this case, a closing lid 83 is attached to the inflow part 81 and the outflow part 82 of the first divided purification part 37f and closed.

  As described above, according to the present embodiment, a portion of the first divided purification unit 37f and the second divided purification unit 37s that is relatively less deteriorated is selected and used during system operation. For this reason, even if the service life is prolonged, the purification ability for purifying the reformed gas is ensured. According to this embodiment, the first divided purification unit 37f and the second divided purification unit 37s can have an open / close lid (not shown). In this case, during regular or irregular maintenance, the maintenance contractor or the user opens the opening / closing lid, and the catalyst carrier at the site where deterioration has progressed in the first divided purification unit 37f and the second divided purification unit 37s. Parts can be exchanged.

  According to the present embodiment, the capacity and the catalyst amount may be basically the same for the first divided purification unit 37f and the second divided purification unit 37s. In addition, among the first divided purification unit 37f and the second divided purification unit 37s, the capacity and the catalyst amount used in the latter half of the useful life increase more than those used in the first half period. be able to. The purifying portion 37D is formed of two divided purifying portions arranged in parallel along the axial direction of the central axis P1 (concentric circular axis), but is not limited to this, and is three, four, or five. Alternatively, it may be formed by six divided purification sections.

  Further explanation will be added. As shown in FIG. 5, the first divided purification unit 37 f includes a casing 370 that is coaxially disposed on the outer peripheral side of the evaporation unit 36, and a monoxide that is coaxially disposed in the casing 370 and included in the reformed gas. A selective oxidation unit 371 that reduces carbon and a methanation reaction unit 372 that is arranged coaxially with the housing 370 and reduces carbon monoxide contained in the reformed gas are provided. The selective oxidation unit 371 is formed of a catalyst carrier that supports a catalyst, and is disposed upstream of the methanation reaction unit 372. That is, the selective oxidation part 371 is formed of a catalyst carrier part supporting a catalyst, and the ratio of reducing the carbon monoxide contained in the reformed gas using oxygen is higher than that using hydrogen. On the other hand, the methanation reaction unit 372 is disposed downstream of the selective oxidation unit 371, and carbon monoxide contained in the reformed gas generated in the reforming unit 34 is metabolized using hydrogen. It is reduced by the nation reaction. That is, in the methanation reaction unit 372, the ratio of reducing carbon monoxide contained in the reformed gas with hydrogen is higher than that with oxygen. The reaction activation temperature in the methanation reaction unit 372 is higher than the reaction activation temperature in the selective oxidation unit 371.

  The selective oxidation part 371 is a first catalyst carrier part having air permeability formed of a ceramic body supporting a catalyst 371e for the selective oxidation part 371 (for example, a ruthenium-based, platinum-based, platinum-ruthenium-based noble metal-based catalyst). 381, a gas permeation jig 383 that forms a ring shape on the lower surface side of the first catalyst carrier portion 381, a gas permeation jig 384 that forms a ring shape on the upper surface side of the first catalyst carrier portion 381, and a gas permeation jig 383 And a lower entrance chamber 385. The inlet 37 i communicates with a ring-shaped inlet chamber 385.

  As shown in FIG. 5, the methanation reaction part 372 is formed of a ceramic body supporting a catalyst 372e for the methanation reaction part 372 (for example, a ruthenium-based, platinum-based, platinum-ruthenium-based noble metal-based catalyst). A second catalyst carrier portion 382 having air permeability is provided. The methanation reaction part 372 includes a second catalyst carrier part 382 formed of a ceramic body supporting a catalyst 372e for the methanation reaction part 372 (for example, a ruthenium-based, platinum-based, platinum-ruthenium-based noble metal-based catalyst). , A gas permeation jig 386 having a ring shape on the lower surface side of the second catalyst carrier portion 382, an outlet chamber 389 below the gas permeation jig 386, and a gas having a ring shape on the upper surface side of the second catalyst carrier portion 382. And a transmission jig 387. The outlet 37p communicates with a ring-shaped outlet chamber 389.

  As shown in FIG. 5, the selective oxidation unit 371 having a cylindrical shape is disposed on the inner peripheral side of the methanation reaction unit 372, and is disposed closer to the evaporation unit 36 than the methanation reaction unit 372. Yes. The selective oxidation unit 371 is adjacent to the evaporation unit 36. The methanation reaction part 372 having a cylindrical shape is disposed on the outer peripheral side of the selective oxidation part 371 and suppresses heat radiation to the outside of the selective oxidation part 371. That is, the methanation reaction unit 372 is disposed farther from the evaporation unit 36 than the selective oxidation unit 371 in the radial direction (arrow R direction) of the reforming unit 34. The methanation reaction unit 372 and the evaporation unit 36 are arranged so as to sandwich the selective oxidation unit 371 in the radial direction (arrow R direction).

  As shown in FIG. 5, in the height direction (arrow H direction), the second catalyst carrier portion 382 and the first catalyst carrier portion 381 are set at a height position so as to overlap each other. Therefore, the heat generated by the reaction in the first catalyst carrier portion 381 is effectively transferred to the second catalyst carrier portion 382. In particular, a ring-shaped partition member 390 made of a metal having heat conductivity is disposed between the first catalyst carrier portion 381 and the second catalyst carrier portion 382. For this reason, the heat generated by the reaction in the first catalyst carrier part 381 of the selective oxidation part 371 is transferred to the second catalyst carrier part 382 of the methanation reaction part 372 via the partition member 390, and the methanation reaction part 372 It is easy to maintain the temperature at a high temperature. Further, since a heat insulating material (not shown) is arranged in a cylindrical shape or a ring shape on the outer peripheral side (outer surface side) of the methanation reaction unit 372, heat radiation of the methanation reaction unit 372 is suppressed, and the methanation reaction unit 372. It is easy to maintain the temperature at a high temperature. However, the partition member 390 may be a ceramic material.

  As shown in FIG. 5, a ring-shaped diffusion promoting chamber 392 that promotes diffusion of the reformed gas is formed between the selective oxidation unit 371 and the methanation reaction unit 372. The diffusion promoting chamber 392 includes a ring-shaped inner space 393 disposed on the outlet side (upper surface side) of the first catalyst carrier portion 381 and a ring shape disposed on the inlet side (upper surface side) of the second catalyst carrier portion 382. The outer space 394 is formed. Since the diffusion accelerating chamber 392 is provided, the reformed gas that has completed the selective oxidation reaction of the selective oxidation unit 371 is diffused in the diffusion accelerating chamber 392, and the uniformity of the gas concentration is increased. The reformed gas having high concentration uniformity is supplied to the methanation reaction section 372 and purified. Therefore, the methanation reaction part 372 can contribute to improvement of reaction uniformity.

  As shown in FIG. 5, the selective oxidation unit of the reforming unit 34, the evaporation unit 36, and the first divided purification unit 37 f from the central axis P <b> 1 of the reforming unit 34 outward in the radial direction (arrow R direction). 371 and the methanation reaction part 372 of the first divided purification part 37f are arranged concentrically in this order.

Further explanation will be added. As shown in FIG. 5, in the selective oxidation unit 371 of the first split purification unit 37f, the oxygen concentration is relatively high because it is close to the inlet 37i to which the oxidizing air is supplied. In contrast, the methanation reaction unit 372 has a relatively lower oxygen concentration than the selective oxidation unit 371. Therefore, in the selective oxidation unit 371, a selective oxidation reaction (exothermic reaction) in which oxygen is consumed easily occurs, and the reaction activation temperature is generally 100 to 200 ° C. On the other hand, in the methanation reaction part 372 located relatively downstream on the side where oxygen is consumed, a methanation reaction (exothermic reaction) using hydrogen is more likely to occur than a selective oxidation reaction using oxygen. . Similar to the selective oxidation reaction, the methanation reaction is also a carbon monoxide purification reaction.
Selective oxidation reaction: CO + 1 / 2O ₂ → CO ₂
Methanation reaction: CO + 3H ₂ → CH ₄ + H ₂ O
By the way, since the evaporation part 36 described above vaporizes water, the operating temperature of the evaporation part 36 is affected by the heat of vaporization of water, and is lower than the temperature of the first divided purification part 37f, and is around 100 ° C. That is, the evaporation part 36 tends to be relatively low temperature due to the influence of the heat of vaporization of water. If the methanation reaction unit 372 of the first divided purification unit 37f is excessively cooled by the evaporation unit 36, the methanation reaction in the methanation reaction unit 372 may be impaired. In particular, since the methanation reaction has a good reaction activation temperature range of 150 to 300 ° C. and a large temperature difference from the operating temperature of the evaporation section 36 (about 100 ° C.), excessive cooling is a good methanation reaction. May be harmful to the purification of carbon monoxide. In this regard, according to the present embodiment, the methanation reaction unit 372 of the first divided purification unit 37f is arranged farther from the evaporation unit 36 than the selective oxidation unit 371. Therefore, the movement of heat from the methanation reaction unit 372 to the evaporation unit 36 of the first divided purification unit 37f is suppressed.

  For this reason, when the reformer 2 is operated, excessive cooling in the methanation reaction unit 372 of the first split purification unit 37f is suppressed. Therefore, the carbon monoxide purification reaction (mainly the methanation reaction) in the methanation reaction unit 372 of the first divided purification unit 37f is favorably performed. In addition, although the purification | cleaning part 37 is formed of the division | segmentation purification | cleaning part 37 arranged in parallel along the axial length direction of the central axis P1 (concentric circular axis), it is 3 or 4 or 5 or 6 pieces. It may be formed by the division purification unit 37.

  FIG. 6 shows Embodiment 6 of the present invention. Embodiment 6 of the present invention will be described below. This embodiment basically has the same configuration and the same function and effect as the fifth embodiment. Hereinafter, a description will be given centering on the difference from the fifth embodiment. As shown in FIG. 6, the first split purification unit 37 f includes an inflow part 81 for allowing the reformed gas to flow in and an outflow part 82 for allowing the reformed reformed gas to flow out. Similarly, the second divided purification unit 37 s includes an inflow part 81 through which the reformed gas flows and an outflow part 82 through which the purified reformed gas flows out. The inflow pipe 75M is connected to the inflow part 81 of the first split purification part 37f and the inflow part 81 of the second split purification part 37s via a three-way valve 75W. The three-way valve 75W is switched between a form in which the inflow pipe 75M and the inflow part 81 of the first split purification part 37f are in communication and a form in which the inflow pipe 75M and the inflow part 81 of the second split purification part 37s are in communication. Further, as shown in FIG. 6, the outflow pipe 100M is connected to the outflow part 82 of the first divided purification unit 37f and the outflow part 82 of the second divided purification unit 37s via the three-way valve 100W. The three-way valve 100W is switched between a form in which the outflow pipe 100M and the outflow part 82 of the first divided purification part 37f are communicated with each other and a form in which the outflow pipe 100M and the outflow part 82 of the second divided purification unit 37s are communicated.

  According to the present embodiment, of the first divided purification unit 37f and the second divided purification unit 37s, the upper first divided purification unit 37f is used in the first half period (initial stage) of the service life, and the lower second division purification unit 37f is used. The division purification unit 37s is not used. In this case, the three-way valve 75W allows the inflow pipe 75M to communicate with the inflow part 81 of the first split purification unit 37f, and the three-way valve 100W allows the outflow pipe 100M to communicate with the outflow part 82 of the first split purification unit 37f. .

  Of the first divided purification unit 37f and the second divided purification unit 37s, the second divided purification unit 37s is used and the first divided purification unit 37f is not used in the latter half of the useful life (end). In this case, the three-way valve 75W allows the inflow pipe 75M to communicate with the inflow part 81 of the second split purification unit 37s, and the three-way valve 100W allows the outflow pipe 100M to communicate with the outflow part 82 of the second split purification unit 37s. .

  According to the present embodiment, when the first split purification unit 37f is being used, if the deterioration of the first split purification unit 37f progresses, the control device operates the three-way valve 75W and the three-way valve 100W to perform the second split purification. Switch to use of unit 37s. The progress of deterioration can be detected by, for example, the CO sensor 100S that detects carbon monoxide contained in the reformed gas flowing through the purified outflow pipe 100M.

  Further, when the second divided purification unit 37s is being used and the deterioration of the second divided purification unit 37s progresses, the control device operates the three-way valve 75W and the three-way valve 100W to use the first divided purification unit 37f. Switch. Then, at the time of regular or irregular maintenance, the catalyst carrier portion of the degraded divided catalyst portion is replaced.

  FIG. 7 shows a seventh embodiment of the present invention. The present embodiment basically has the same configuration and the same function and effect as the first embodiment. Hereinafter, the description will focus on the different parts. As shown in FIG. 7, the purification unit 37E includes a first divided purification unit 37f having a cylindrical shape integrally held outside the evaporation unit 36 (in FIG. 7, the first divided purification unit 37f having a cylindrical shape). The right half is not shown) and a separation-type second divided purification unit 37 s separated from the evaporation unit 36. The first divided purification unit 37f includes a housing 370 that is integrally disposed on the outer peripheral side of the evaporation unit 36, and a selective oxidation unit 371 that is disposed in the housing 370 and reduces carbon monoxide contained in the reformed gas. And a methanation reaction section 372 that is disposed in the housing 370 and reduces carbon monoxide contained in the reformed gas.

  As shown in FIG. 7, the second divided purification unit 37s includes a casing 379 that is separated from the casing 370 on the reforming unit 34 side, a catalyst carrier unit 382 that is accommodated in the casing 379, A gas permeation jig 386 on the lower surface side of the catalyst carrier part 382, an inlet chamber 385 below the gas permeation jig 386, a gas permeation jig 387 on the upper surface side of the second catalyst carrier part 382, and a gas permeation jig 387. An outlet chamber 389, an inflow portion 81 connected to the inlet chamber 385, an outflow portion 82 connected to the outlet chamber 389, and a heating passage 380 formed of a hollow pipe. The upstream region 382u of the catalyst carrier portion 382 is mainly a selective reaction portion because oxygen is rich, and the downstream region 382d of the catalyst carrier portion 382 is mainly a methanation reaction portion because oxygen is scarce.

  Of the first divided purification unit 37f and the second divided purification unit 37s, the first divided purification unit 37f is used and the second divided purification unit 37s is not used in the first half period (initial stage) of the service life. For this reason, first, the connector 75N of the inflow piping 75M is connected to the inflow portion 81 of the first split purification portion 37f, and the connector 100N of the outflow piping 100M is connected to the outflow portion 82 of the first split purification portion 37f. In this case, a closing lid 83 is attached to the inflow portion 81 and the outflow portion 82 of the second divided purification portion 37s that are not used, and is closed in a sealed state.

  On the other hand, in the second half period (end) of the service life, the separation-type second divided purification unit 37s is used, and the first divided purification unit 37f is not used. In this case, the piping path is switched so that the water vapor discharged from the evaporation section 36 or a heat medium such as combustion exhaust gas flows through the heating passage 380, and the second catalyst carrier section 382 of the second divided purification section 37s is used for the purification reaction. Heat to suit. Further, the connector 75N of the inflow pipe 75M is connected to the inflow part 81 of the second split purification unit 37s, and the connector 100N of the outflow pipe 100M is connected to the outflow part 82 of the second split purification unit 37s. In this case, the inflow part 81 and the outflow part 82 of the 1st division | segmentation purification | cleaning part 37f which are not used are closed with a cover part.

  As described above, according to the present embodiment, the portion of the first divided purification unit 37f and the second divided purification unit 37s that has relatively little deterioration is used during system operation. For this reason, even if the service life is prolonged, the purification ability for purifying the reformed gas is ensured. According to the present embodiment, during regular or irregular maintenance, the maintenance contractor or user replaces the part of the first divided purification unit 37f and the second divided purification unit 37s that have deteriorated.

  According to the present embodiment, the capacity and the catalyst amount may be basically the same for the first divided purification unit 37f and the second divided purification unit 37s. In addition, among the first divided purification unit 37f and the second divided purification unit 37s, the capacity and the catalyst amount used in the latter half of the useful life increase more than those used in the first half period. be able to. In the present embodiment, as shown in FIG. 5, the purification unit 37E includes a first divided purification unit 37f having a cylindrical shape integrally held outside the evaporation unit 36, and a separation type separated from the evaporation unit 36. Although it is provided with the second divided purification unit 37s, the present invention is not limited to this, but although not shown, it may be a separation type in which both the first divided purification unit 37f and the second divided purification unit 37s are separated from the reforming unit 34. good.

(Other)
The present invention is not limited to the above-described embodiments, and can be implemented with appropriate modifications within a range not departing from the gist. In the first embodiment, the evaporation unit 36 is integrated with the reforming unit 34, but the present invention is not limited thereto, and the evaporation unit 36 may be separated from the reforming unit 34. In the first embodiment, the first divided purification unit 37f and the second divided purification unit 37s are used in this order, but the reverse is also possible. The purification unit 37 may be divided in the circumferential direction around the central axis P1 and may be divided along the axial length direction of the central axis P1. In Example 1, although the purification | cleaning part 37 and the evaporation part 36 are arrange | positioned coaxially, it may not be coaxial, a non-coaxial type may be sufficient, and the lamination | stacking type laminated | stacked on the thickness direction may be sufficient. Each catalyst is not limited to those described above. As shown in FIG. 1, the shift unit 5 is integrally connected to the reforming unit 34. However, the present invention is not limited to this, and the shift unit 5 may be separated from the reforming unit 34. As shown in FIG. 1, the reforming unit 34 is disposed above the CO shift unit 5. However, the present invention is not limited thereto, and the reforming unit 34 may be disposed below or beside the CO shift unit 5. good.

  The present invention can be used in a reforming system used in a fuel cell system or the like.

1 is a diagram illustrating an entire reforming system according to Embodiment 1. FIG. 1 is a cross-sectional view illustrating a main part of a reforming system according to Example 1. FIG. It is sectional drawing which concerns on Example 4 and shows the principal part of a reforming system. It is sectional drawing in a different direction which concerns on Example 4 and shows the plane form of the principal part of a reforming system. FIG. 10 is a cross-sectional view showing a main part of a reforming system according to Example 5. FIG. 10 is a cross-sectional view showing the main part of the reforming system according to Example 6. FIG. 10 is a cross-sectional view showing a main part of a reforming system according to Example 7.

Explanation of symbols

  1 is a fuel cell, 2 is a reformer, 30 is a combustion unit, 34 is a reforming unit, 36 is an evaporation unit, 37 is a purification unit, 37f is a first division purification unit, 37s is a second division purification unit, and 75M is An inflow pipe, 100M is an outflow pipe, 81 is an inflow part, and 82 is an outflow part.

Claims (11)

A fuel cell comprising: a reforming unit that reforms a reforming raw material to generate a reforming fluid; and a purification unit that purifies the reforming fluid by reducing a load substance contained in the reforming fluid. In the reforming system for
The purifying unit is configured to be able to switch a use part in the purifying part with time so that a part of the purifying part with relatively little deterioration is used during system operation. Reforming system.   2. The use part in the purification unit is switched over time during regular or irregular maintenance so that a part of the purification unit that is relatively less deteriorated is used during system operation. A fuel cell reforming system characterized by being made possible.   3. The fuel cell reforming system according to claim 1, wherein the part of the purification unit where deterioration has progressed is replaced during regular or irregular maintenance. In one of Claims 1-3, the site | part which deterioration progressed by the system operation | movement among the said purification | cleaning parts is switched to the site | part with little deterioration among the said purification | cleaning parts in the normal driving | operation of a system,
A reforming system for a fuel cell, characterized in that a portion of the purifying section where deterioration has progressed can be replaced during regular or irregular maintenance.   In one of Claims 1-4, the said purification part is formed in the division purification part divided into plurality, and uses the division purification part with relatively little deterioration at the time of operation, The reforming system for a fuel cell, characterized in that the division purification unit can be switched over time.   In Claim 5, each said division | segmentation purification | cleaning part is the outflow from which the inflow piping which flows in the reforming fluid before purification | cleaning is detachably attached, and the outflow which flows out the reforming fluid after the purification | cleaning which reduced the load substance A reforming system for a fuel cell, comprising an outflow part to which a pipe is detachably attached.   7. The fuel cell reforming system according to claim 5, wherein each of the divided purification units is disposed along a circumferential direction of a concentric circular axis.   6. The reforming system for a fuel cell according to claim 5, wherein each of the divided purification sections is disposed along an axial length direction of a concentric circular axis.   9. The capacity of the split purification unit used at the end of the useful life of the system according to claim 5 is set to be larger than the capacity of the split purification unit used at the beginning of the useful life of the system. A fuel cell reforming system characterized by the above.   9. The catalyst in each of the split purification sections according to claim 5, wherein the catalyst in each of the split purification sections is the same system, and the amount of catalyst in the split purification section used at the end of the service life of the system is at the initial stage of the system service life. A reforming system for a fuel cell, wherein the amount is set to be larger than the catalyst amount in the divided purification unit used.   11. The reforming unit according to claim 1, wherein the reforming unit reforms a reforming raw material to generate a reformed gas, and the purification unit is included in the reformed gas. A reforming system for a fuel cell that purifies the reformed gas by reducing carbon monoxide.

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