JP4870499B2 - Hydrogen production apparatus and fuel cell power generation apparatus - Google Patents

Description

  The present invention relates to a hydrogen production apparatus for producing a reformed gas that is rich in hydrogen and from which carbon monoxide has been removed using a hydrocarbon-based fuel such as city gas or LPG, and a reformed gas produced by the hydrogen production apparatus. The present invention relates to a fuel cell power generation device including a fuel cell that generates power using the power.

  The fuel cell power generation apparatus is mainly composed of a hydrogen production apparatus that produces a hydrogen-rich reformed gas and a fuel cell that generates power using the reformed gas produced by the hydrogen production apparatus.

  The hydrogen production apparatus uses a hydrocarbon-based fuel such as city gas or LPG as a raw material gas, and a reforming unit that generates a reformed gas mainly composed of hydrogen by performing a steam reforming reaction between the raw material gas and water. And a carbon monoxide removing unit that removes carbon monoxide having a poisoning action on the catalyst of the fuel cell from the reformed gas. Here, when a polymer electrolyte fuel cell is used as the fuel cell, the carbon monoxide concentration contained in the reformed gas needs to be removed to about 10 ppm. Therefore, the carbon monoxide removal unit is based on a CO conversion catalyst. Selective oxidation that reduces carbon monoxide to about 10 ppm or less by further removing carbon monoxide by selective oxidation reaction using a CO selective oxidation catalyst and removing carbon monoxide by about 0.5% by CO aquatic modification reaction In general, it is formed in a two-stage configuration.

  Patent document 1 etc. are proposed as such a hydrogen production apparatus, An example is shown in FIG. The apparatus shown in FIG. 4 is composed of a cylindrical body 3 in which an inner cylinder 1 and an outer cylinder 2 are arranged concentrically. A combustion section 4 made of a burner or the like is provided in the inner cylinder 1 to generate combustion gas and combustion. Gas is allowed to flow through the combustion gas flow path 5 on the inner periphery of the inner cylinder 1. A preheating evaporation section 6 is formed along the outer periphery of the inner cylinder 1, and a reforming section 8 is formed below the preheating evaporation section 6. Further, a carbon monoxide removing unit 10 is provided in contact with the pre-evaporating unit 6 at the upper part of the inner periphery of the outer cylinder 2, and the carbon monoxide removing unit 10 is formed of a shift conversion unit 10a and a selective oxidation unit 10b. .

  The raw material gas is supplied from the raw material supply unit 25 and the water is supplied from the water supply unit 26 to the preheating evaporation unit 6, and the heating from the combustion gas flow path 5 and the heat from the carbon monoxide removal unit 10 are performed. By the heating by exchange, the raw material gas and water are heated and the water is evaporated, and a mixed gas of the raw material gas and water vapor is generated in the preheating evaporation unit 6. This mixed gas flows into the reforming unit 8, and the raw material gas and steam undergo a steam reforming reaction by the action of the reforming catalyst, and a hydrogen-rich reformed gas is generated. Since the steam reforming reaction is an endothermic reaction, the reforming unit 8 receives heat from the combustion gas flow path 5. Next, the reformed gas generated in the reforming unit 8 is sent to the carbon monoxide removing unit 10 through the heat exchange flow path 27. When the reformed gas passes through the heat exchange flow path 27, heat exchange is performed with the reforming unit 8. In the shift unit 10a of the carbon monoxide removal unit 10, carbon monoxide in the reformed gas is removed by the CO aquatic shift reaction by the action of the CO shift catalyst, and in the selective oxidation unit 10b, the CO selective oxidation catalyst. The carbon in the reformed gas is further removed by the CO selective oxidation reaction with oxygen in the air supplied from the air supply unit 28 by the action. Thus, the reformed gas from which carbon monoxide has been removed by the carbon monoxide removing unit 10 is supplied to the fuel cell 14 and the like.

In the apparatus of FIG. 4, the reforming unit 8, the carbon monoxide removal unit 10, and the preheating evaporation unit 5 are concentrically used in order to effectively use the heat generated from the reforming unit 8 and the carbon monoxide removal unit 10 with high heat conversion efficiency. The combustion gas flow path 5 is arranged inside the inner cylinder 1 so that the temperature of the reforming section 8 and the carbon monoxide removal section 10 is set to a temperature suitable for the reaction. The heat exchange flow path 27 is arranged outside the reforming unit 8.
JP 2001-180911 A

  However, when the amount of raw material gas or the amount of water supplied from the raw material supply unit 25 or the water supply unit 26 to the preheating evaporation unit 6 varies with the reaction load of the fuel cell, the raw material in the preheating evaporation unit 6 The mixing state and temperature of the gas and water vapor vary, the catalyst temperature of the reforming unit 8 into which the raw material gas and water vapor flow becomes unstable, and between the preheating evaporation unit 6 and the carbon monoxide removal unit 10. Due to excessive heat transfer or insufficient heat transfer, the catalyst temperature of the carbon monoxide removal unit 10 becomes unstable. As a result, the methane conversion rate of the reforming reaction in the reforming unit 8 decreases, and the carbon monoxide removal unit 10 There is a possibility that the carbon monoxide removing ability in the reformed gas at the time may decrease.

  In particular, when the amount of raw material gas or water supplied to the preheating evaporation unit 6 is the maximum amount, the water does not completely evaporate in the preheating evaporation unit 6 and remains in the reforming unit 8 as water. Will flow in. Therefore, in this case, the reforming section 8 is cooled by water, the catalyst temperature is lowered, and the temperature of the reformed gas exiting the reforming section 8 is also lowered, so that the carbon monoxide from which the reformed gas flows is removed. The temperature of the section 10 becomes lower than the temperature suitable for the CO shift reaction, and as a result, the capacity of the reforming reaction in the reforming section 8 and the capacity of removing carbon monoxide in the carbon monoxide removing section 10 are lowered. There was a problem of becoming.

  Conversely, when the amount of raw material gas or water supplied to the preheating evaporator 6 is a minimum amount, the water is superheated in the preheating evaporator 6 to become high temperature superheated steam, The catalyst temperature of the reforming section 8 that flows in becomes too high, and the inlet temperature of the carbon monoxide removal section 10 that exchanges heat with the preheating evaporation section 6 exceeds 300 ° C., resulting in a catalyst temperature that is not suitable for the CO shift reaction. In this case as well, there is a problem that the ability of the reforming reaction in the reforming unit 8 and the ability of removing carbon monoxide in the carbon monoxide removing unit 10 are reduced.

  The present invention has been made in view of the above points, and even if the amount of raw material gas and water supplied to the preheating evaporation unit varies, the state of the raw material gas and water vapor before flowing into the reforming unit is stabilized. Production apparatus capable of maintaining the temperature of the reforming section and the carbon monoxide removal section appropriately and stably producing the reformed gas rich in hydrogen and from which carbon monoxide is removed Is intended to provide.

  The hydrogen production apparatus according to claim 1 of the present invention includes a cylinder 3 provided with an inner cylinder 1 and an outer cylinder 2, and combustion in which combustion gas provided along the inner periphery of the inner cylinder 1 flows in the combustion section 4. The gas flow path 5 is disposed along the inner cylinder 1 between the inner cylinder 1 and the outer cylinder 2, the raw material gas and water are supplied, and water is evaporated by heating from the combustion gas flow path 5. The preheating evaporator 6 for heating the raw material gas, and the inner gas 1 and the outer tube 2 are disposed between the inner cylinder 1 and the outer cylinder 2 and formed with the reforming catalyst 7. The reformer 8 is formed between the inner cylinder 1 and the outer cylinder 2 and is provided with a carbon monoxide removal catalyst 9, and is formed from the reformer 8. A hydrogen production apparatus comprising a carbon monoxide removal unit 10 for removing carbon monoxide in a supplied reformed gas, The first evaporation unit 6a is disposed below the first evaporation unit 6a, the first evaporation unit 6a is disposed at a position where heat exchange with the carbon monoxide removal unit 10 is possible, and the first evaporation unit 6a. And a partition wall 11 that surrounds the side and the bottom of the second evaporation unit 6b, and an opening 12 is formed above the partition wall 11. A guide path 13 is formed between the second evaporation section 6b and the outer cylinder 1 side where the water vapor evaporated by the first evaporation section 6a and the water vapor evaporated by the second evaporation section 6b merge, and the opening 12 and the reforming section. 8, a mixed gas flow path 14 is formed in which the raw material gas and the water vapor that are supplied from the preheating vaporization section 6 through the induction path 13 and pass through the opening 12 are circulated to be supplied to the reforming section 8. It is what.

  According to the present invention, when the amount of the raw material gas and the amount of water supplied to the preheating evaporator 6 are large and the water does not completely evaporate in the first evaporator 6a of the preheating evaporator 6, The water vapor evaporated in the second evaporator 6b, the water vapor evaporated in the first evaporator 6a and the water vapor evaporated in the second evaporator 6b are merged in the induction path 13, and the water vapor is reformed through the mixed gas channel 14 from the opening 12. In addition to being able to be supplied to the unit 8, the non-evaporated water that has flowed into the second evaporation unit 6 b from the first evaporation unit 6 a stays in the lower part of the partition wall 11, and the non-evaporated water flows into the reforming unit 8. Can be prevented. Further, the amount of the raw material gas and the amount of water supplied to the preheating evaporation unit 6 are small, and the water vapor evaporated in the first evaporation unit 6a of the preheating evaporation unit 6 is further heated in the second evaporation unit 6b to generate high-temperature superheated steam. In this case, the low-temperature steam in the first evaporator 6a and the high-temperature superheated steam in the second evaporator 6b are merged in the induction path 13 to become appropriate-temperature steam, and the high-temperature steam flows into the reforming section 8. Can be prevented. Furthermore, when the raw material gas and water vapor flowing from the preheating evaporator 6 through the induction path 13 pass through the opening 12, the flow velocity is increased to promote the mixing of the raw material gas and the water vapor, and the mixed gas is uniformly mixed. It can be supplied from the gas flow path 14 to the reforming unit 8.

  The invention of claim 2 is characterized in that, in claim 1, the preheating evaporation section 6 is formed as a spiral flow path that circulates along the inner cylinder 1.

  According to this invention, the preheating evaporation part 6 can be formed as a spiral long flow path, and the mixing efficiency of fuel gas and the water vapor | steam which evaporated water can be improved.

  The invention of claim 3 is characterized in that, in claim 1 or 2, the second evaporator 6b is filled with the good heat conductor 15.

  According to the present invention, the non-evaporated water that has flowed into the second evaporation unit 6b from the first evaporation unit 6a can be efficiently heated by the good heat conductor 15, and the non-evaporation in the second evaporation unit 6b. The evaporation efficiency of water can be increased.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the reformed gas flow path 16 that circulates the reformed gas generated in the reforming section 8 and supplies the reformed gas to the carbon monoxide removing section 10; The mixed gas flow path 14 is arranged at an adjacent position where heat exchange is possible.

  According to the present invention, the reformed gas supplied from the reforming unit 8 to the carbon monoxide removing unit 10 is adjusted to an appropriate temperature by heat exchange between the reformed gas channel 16 and the mixed gas channel 14. can do.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the temperature detector 17 is provided in the opening 12, and combustion of the combustion section 4 is performed while maintaining the temperature of the opening 12 at a predetermined constant temperature. This is characterized in that the non-evaporated water staying in the second evaporator 6b is evaporated by being controlled.

  According to the present invention, the combustion amount of the combustion unit 4 is increased in a range where the temperature of the water vapor passing through the opening 12 does not exceed the predetermined temperature, and the evaporation of unevaporated water staying in the second evaporation unit 6b is promoted. It is something that can be done.

  Further, in the invention of claim 6, in any one of claims 1 to 5, when water is heated and evaporated in the preheating evaporator 6, the water is separated from the first evaporator 6 a to the second evaporator 6 b. It is characterized by being sent in a gas-phase two-phase flow.

  According to the present invention, the water supplied to the preheating evaporator 6 is such that part of the water evaporates in the first evaporator 6a and the remaining water evaporates in the second evaporator 6b. It is possible to suppress the formation of high-temperature superheated steam at the part 6b, and the steam from the first evaporation part 6a and the steam from the second evaporation part 6b are merged in the induction path 13 to form steam at an appropriate temperature from the opening 12 It can be supplied to the reforming unit 8.

  According to a seventh aspect of the present invention, there is provided a fuel cell power generation apparatus comprising: the hydrogen production apparatus according to any one of the first to sixth aspects; the reformed gas supplied from the hydrogen production apparatus; and an oxidizing gas containing oxygen. And a fuel cell 18 that generates electric power by using the fuel cell.

  The reformed gas produced by the hydrogen production apparatus is one in which carbon monoxide is stably removed, and power generation can be performed by the fuel cell 18 without fear of deterioration due to poisoning by carbon monoxide. Is.

  According to the present invention, when the amount of raw material gas and the amount of water supplied to the preheating evaporator 6 are large and the water does not completely evaporate in the first evaporator 6a of the preheating evaporator 6, The water vapor evaporated in the second evaporator 6b, the water vapor evaporated in the first evaporator 6a and the water vapor evaporated in the second evaporator 6b are merged in the induction path 13, and the water vapor is reformed through the mixed gas channel 14 from the opening 12. The non-evaporated water flowing into the second evaporation unit 6b from the first evaporation unit 6a stays in the lower part (bottom part) 11a of the partition wall 11, and the unevaporated water is supplied to the reforming unit. 8, the amount of raw material gas and water supplied to the preheating evaporator 6 are small, and the water vapor evaporated in the first evaporator 6 a of the preheat evaporator 6 is the first. When the second evaporator 6b is further heated to become high-temperature superheated steam, the first evaporator 6 The low temperature steam and high-temperature superheated steam of the second evaporator section 6b becomes steam TEMPERATURE merges with taxiway 13, in which it is possible to prevent the high-temperature steam flows into the reformer 8. Furthermore, when the raw material gas and water vapor flowing from the preheating evaporator 6 through the induction path 13 pass through the opening 12, the flow velocity is increased to promote the mixing of the raw material gas and the water vapor, and the mixed gas is uniformly mixed. The gas can be supplied from the gas flow path 14 to the reforming unit 8. As a result, even if the amount of the raw material gas and water supplied to the preheating evaporation unit 6 fluctuates, the state of the raw material gas and water vapor before flowing into the reforming unit 8 can be stabilized, and the reforming unit 8 In addition, the temperature of the carbon monoxide removal unit 10 can be maintained appropriately, and the reformed gas that is rich in hydrogen and from which carbon monoxide has been removed can be stably produced.

  Hereinafter, the best mode for carrying out the present invention will be described.

  FIG. 1 shows an example of an embodiment of the present invention. A cylindrical body 3 serving as a casing of the apparatus has a cylindrical inner cylinder 1 and an outer cylinder 2 arranged concentrically with the axial direction vertical. Formed. In this cylindrical body 3, the upper and lower ends of the cylindrical space between the inner cylinder 1 and the outer cylinder 2 are closed. A combustion part 4 made of a burner is provided at the center of the inner circumference of the inner cylinder 1, and combustion air is blown from a combustion fan 31. A combustion gas flow path 5 is formed between the combustion section 4 and the inner cylinder 1 along the inner periphery of the inner cylinder 1, and the combustion gas burned in the combustion section 4 flows along the combustion gas flow path 5. It is like that.

  In the upper part of the cylindrical space between the inner cylinder 1 and the outer cylinder 2, a preheating evaporator 6 is provided on the inner cylinder 1 side, and a carbon monoxide removing part 10 is provided concentrically on the outer cylinder 2 side. The preheating evaporation unit 6 is formed as a cylindrical space along the outer surface of the inner cylinder 1, and the carbon monoxide removal unit 10 is formed in a cylindrical shape in contact with the outer surface of the preheating evaporation unit 6. A source gas supply unit 25 and a water supply unit 26 are connected to the upper end of the preheating evaporation unit 6. A reforming unit 8 is provided below the lower end of the preheating evaporation unit 6. The reforming part 8 is formed in a cylindrical shape in contact with the inner surface of the inner cylinder 1.

  The preheating evaporator 6 is formed by an upper first evaporator 6a and a lower second evaporator 6b. The upper first evaporator 6a is in contact with the carbon monoxide remover 10 so that the first evaporator 6a and the carbon monoxide remover 10 can exchange heat with each other, and the lower second evaporator 6b. Is positioned below the lower end of the carbon monoxide removal unit 10. In the cylindrical space of the preheating evaporator 6, a spiral guide body 33 is attached to the entire length from the upper end of the first evaporator 6a to the lower end of the second evaporator 6b. The guide body 33 is formed to have a diameter equal to the space thickness of the preheating evaporation section 6, and thus the cylindrical space of the preheating evaporation section 6 is partitioned by the spiral guide body 33 and circulates along the outer periphery of the inner cylinder 1. It is formed as a spiral channel.

  The first evaporator 6 a is surrounded by the inner cylinder 1 and the carbon monoxide removing unit 10, but the second evaporator 6 b is surrounded by the inner cylinder 1 and the partition wall 11. As shown in FIG. 2, the partition wall 11 is formed in an L-shaped cross section from the side surface on the outer cylinder 3 side of the second evaporator 6 b to the bottom surface, and the upper end of the side portion of the partition wall 11 is the carbon monoxide removal unit 10. The inner peripheral end of the lower part of the partition wall 11 is connected to the outer peripheral surface of the inner cylinder 1 at the lower end of the inner cylinder 1. An opening 12 is opened at the upper end of the side of the partition wall 11. The opening 12 is provided with a temperature detector 17 such as a temperature sensor. Further, a partition plate 35 is provided on the inner side of the partition wall 11 so as to extend flush with the outer surface of the first evaporation unit 6a (also the inner surface of the carbon monoxide removal unit 10), and between the partition wall 11 and the inner cylinder 1. A space in the partition wall 11 is divided into an inner second evaporator 6b and an outer guide path 13. The guide path 13 is formed as a cylindrical space surrounding the second evaporator 6b, and the partition plate 35 has communication ports 36 opened at a plurality of positions on the upper and lower sides.

  Between the upper end of the outer peripheral surface of the reforming unit 8 and the lower surface of the carbon monoxide removing unit 10, a cylindrical heat exchange plate 38 parallel to the inner cylinder 1 and the outer cylinder 2 is attached outside the partition wall 11. The mixed gas flow path 14 is formed between the heat exchange plate 38 and the partition wall 11, and the reformed gas flow path 16 is formed between the heat exchange plate 38 and the outer cylinder 2. The mixed gas channel 14 is a channel that connects the opening 12 of the partition wall 11 and the inlet 39 at the upper end of the reforming unit 8, and the reformed gas channel 16 is a flow provided at the lower periphery of the reforming unit 8. It is a flow path connecting the outlet 40 and the inlet 41 at the lower end of the carbon monoxide removing unit 10.

  The reforming section 8 is formed by filling the reforming catalyst 7. Further, the carbon monoxide removal unit 10 has a two-stage configuration of a conversion unit 10a filled with a CO conversion catalyst as the carbon monoxide removal catalyst 9 and a selective oxidation unit 10b filled with a CO selective oxidation catalyst as the carbon monoxide removal catalyst 9. It is formed with. The transformation unit 10a is disposed on the lower side and the selective oxidation unit 10b is disposed on the upper side so that the transformation unit 10a is the former stage and the selective oxidation unit 10b is the latter stage in the flow direction of the reformed gas. Air is supplied from the air supply section 28 between the sections 10b. The outlet of the upper end of the carbon monoxide removing unit 10 is connected to the fuel cell 18.

  In the hydrogen production apparatus formed as described above, the preheating evaporation section 6 is heated by the combustion gas flowing through the combustion gas flow path 5, and after the operation of the hydrogen production apparatus is started, the carbon monoxide removal section 10 The reaction heat of the CO shift reaction and CO selective oxidation reaction is transferred and heated. When a hydrocarbon-based source gas such as city gas or LPG is supplied from the source gas supply unit 25 and water is supplied from the water supply unit 26 to the preheating evaporation unit 6, the source gas and water are supplied to the preheating evaporation unit 6. Heat is passed while passing from the first evaporator 6a to the second evaporator 6b, and the water evaporates to become water vapor. The heated mixed gas of raw material gas and water vapor passes through the communication port 36 of the partition plate 35 and flows into the guide path 13, and further passes through the opening 12 of the partition wall 11 and flows into the mixed gas flow path 14. Next, the mixed gas of the raw material gas and the steam flows through the mixed gas flow path 14 and flows into the reforming section 8 from the inlet 39, and the raw material gas and the steam undergo a steam reforming reaction by the catalytic action of the reforming catalyst 7. A hydrogen-rich reformed gas is generated. Since the steam reforming reaction is an endothermic reaction, the reforming unit 8 is heated by the combustion gas flowing through the combustion gas flow path 5.

  Here, in order to properly perform the steam reforming reaction in the reforming unit 8, in addition to the temperature of the reforming catalyst in the reforming unit 8 being appropriate, the raw material gas supplied to the reforming unit 8 and It is necessary that the water vapor is sufficiently mixed. Therefore, in the present invention, as described above, the spiral guide body 33 extending from the upper end portion of the first evaporation portion 6a to the lower end portion of the second evaporation portion 6b is provided in the cylindrical space of the preheating evaporation portion 6 so as to preheat evaporation. The portion 6 is formed as a spiral channel, and the channel through which the source gas and water vapor pass is lengthened so that the source gas and water vapor are sufficiently mixed, and the source gas and water vapor are uniformly mixed. The mixed gas is supplied to the reforming unit 8. Further, after the raw material gas and water vapor are allowed to flow from the first evaporation section 6a and the second evaporation section 6b into the induction path 13, and then flow out to the mixed gas flow path 14 through the opening 12, the induction path 13 When the raw material gas or water vapor passes through the opening 12, the flow path is narrowed and the flow velocity is increased, so that the water vapor and the raw material gas are sufficiently mixed, and mixed as a uniform mixed gas. The gas can be supplied from the gas flow path 14 to the reforming unit 8.

  The reformed gas generated in the reforming unit 8 flows out from the outlet 40 at the lower end of the reforming unit 8 to the reformed gas channel 16 and is reformed when rising in the reformed gas channel 16. Heat is exchanged with the part 8 and heat exchange with the mixed gas flowing through the mixed gas flow path 14 through the heat exchange plate 38, and the reformed gas is lowered to a temperature suitable for the reaction in the carbon monoxide removing part 10.

  Next, the reformed gas flows into the shift portion 10a of the carbon monoxide removal portion 10 from the inlet 41 at the lower end, and the carbon monoxide in the reformed gas is removed by the CO shift reaction. Here, the temperature suitable for the CO shift reaction in the shift section 10a is 200 to 250 ° C., where the temperature near the inlet 41 is lower than the temperature of the reformed gas flowing out from the reformer section 8, so that it is as described above. When the reformed gas flows through the reformed gas channel 16, the temperature is lowered to 200 to 250 ° C. by exchanging heat with the mixed gas in the mixed gas channel 14. The reformed gas from which carbon monoxide has been removed in the shift unit 10a further flows into the selective oxidation unit 10b, and undergoes a CO selective oxidation reaction with oxygen in the air supplied from the air supply unit 28 by the action of the CO selective oxidation catalyst. Thus, carbon monoxide in the reformed gas is further removed.

  The reformed gas from which carbon monoxide has been removed by the carbon monoxide removing unit 10 in this way flows out of the carbon monoxide removing unit 10 and is supplied to the fuel cell 18. In the fuel cell 18, power generation is performed using hydrogen in the reformed gas thus supplied from the hydrogen production apparatus and an oxidizing gas containing oxygen such as air.

  Here, when generating power in the fuel cell 18 using the reformed gas supplied from the hydrogen production apparatus as described above, depending on the change in the reaction load of the fuel cell 18, that is, the change in the consumption of the reformed gas. The amount of source gas and the amount of water supplied from the source gas supply unit 25 and the water supply unit 26 to the preheating evaporation unit 6 vary. As described above, when the amount of raw material gas or water supplied to the preheating evaporation unit 6 reaches the maximum amount, the water is not completely evaporated in the preheating evaporation unit 6 and the water is modified. When flowing into the mass part 8, the reforming part 8 is cooled with water, the catalyst temperature is lowered, the temperature of the reformed gas coming out of the reforming part 8 is also lowered, and the temperature of the carbon monoxide removal part 10 is CO-transformed. The temperature may be lower than the temperature suitable for the reaction, and conversely, when the amount of the raw material gas supplied to the preheating evaporation unit 6 or the amount of water becomes the minimum amount, the water is in the preheating evaporation unit 6. Is heated to high temperature superheated steam, the catalyst temperature of the reforming unit 8 becomes too high, and the carbon monoxide removing unit 10 also becomes a catalyst temperature unsuitable for the transformation temperature, and the reforming reaction in the reforming unit 8 The ability and the removal ability of carbon monoxide in the carbon monoxide removal unit 10 are reduced.

  Therefore, the present invention is such that the preheating evaporation section 6 of the hydrogen production apparatus is configured as described above. That is, when the amount of source gas supplied to the preheating evaporator 6 and the amount of water are large, the water is not evaporated in the first evaporator 6a of the preheat evaporator 6, but the flow of the first evaporator 6a is not increased. Since the guide body 33 is formed in a spiral flow path so as to secure a heat transfer area from the combustion gas flow path 5 and the carbon monoxide removal unit 10, water is an unvaporized water phase and evaporated water vapor. It becomes a two-phase with a gas phase, and flows in the spiral flow path of the first evaporator 6a in this two-phase state. At this time, unevaporated water flows down along the upper surface of the guide body 33, and water vapor flows along the space portion of the spiral flow path between the guide bodies 33, and the first evaporation section in a two-phase flow state. It flows into the 2nd evaporation part 6b from 6a. Thus, since the two-phase flow flows from the first evaporator 6a to the second evaporator 6b, the temperature of the water vapor coming out of the first evaporator 6a is about 100 ° C.

  Of the two-phase flow that flows from the first evaporator 6a to the second evaporator 6b, the water that has not evaporated evaporates by heating from the combustion gas flow path 5 in the second evaporator 6b and becomes water vapor. At this time, when the supply amount of water is the maximum amount, the second evaporation unit 6b may not evaporate completely, but even if there is unevaporated water in this way, the water is below the partition wall 11 (bottom). The water stays in 11a and water does not flow into the reforming section 8. Of the two-phase flow that flows from the first evaporator 6a to the second evaporator 6b, the water vapor is superheated by the second evaporator 6b to become superheated steam at 150 ° C. or more, but directly from the first evaporator 6a. The water vapor that flows into the induction path 13 through the communication port 36, the water vapor that evaporates at the second evaporation unit 6b and flows into the induction path 13 through the communication port 36, and is heated by the second evaporation unit 6b and is connected to the communication port This superheated steam that flows into the induction path 13 through 36 is mixed in the induction path 13 and passes through the opening 12 as water vapor having an appropriate temperature of about 150 ° C.

  Here, the temperature of the water vapor and the raw material gas passing through the opening 12 is maintained at a predetermined constant temperature of, for example, about 150 ° C. in order to keep the temperature of the reforming unit 8 and the carbon monoxide removal unit 10 appropriately. However, when the amount of water supplied to the preheating evaporation unit 6 is as large as the maximum amount, the second evaporation unit 6b does not completely evaporate the water and the unevaporated water stays in the opening. The temperature of the part 12 may be lower than 150 ° C. Therefore, the temperature of the opening 12 is constantly monitored by the temperature detection unit 17, and when the temperature of the opening 12 is lower than 150 ° C., the control unit (not shown) controls the amount of combustion heat in the combustion unit 4, and the combustion gas flow Control is performed so as to increase the heating temperature of the second evaporator 6b through the path 5, and the evaporation of water in the second evaporator 6b is promoted.

  The raw material gas and water vapor flowing into the induction path 13 from the first evaporation section 6a and the second evaporation section 6b are mixed when passing through the opening 12, and are sent to the mixed gas flow path 14 as a mixed gas. The mixed gas flowing through the flow path 14 is heated by heat exchange with the reformed gas flowing through the reformed gas flow path 16. The mixed gas flowing in the mixed gas flow path 14 is also heat-exchanged with the gas in the induction path 13 through the partition wall 11, but when the amount of water supplied is large, the temperature in the induction path 13 is lower than in the normal case. The heating temperature of the gas is also slightly lower than usual, and is supplied to the reforming unit 8 as a mixed gas having a temperature of about 350 ° C.

  When the temperature of the mixed gas supplied to the reforming unit 8 is about 350 ° C., the temperature of the reformed gas generated in the reforming unit 8 and exiting from the outlet 40 of the reforming unit 8 is about 400 ° C. When the reformed gas flows through the reformed gas channel 16, the temperature is lowered by the heat exchange with the mixed gas in the mixed gas channel 14, and the temperature is reduced to about 200 ° C. The carbon monoxide removal unit 10 To be supplied.

  On the other hand, when the amount of raw material gas or the amount of water supplied to the preheating evaporator 6 is small, all of the water is evaporated while passing through the first evaporator 6a, but this water vapor is superheated in the first evaporator 6a. The heat transfer area of the spiral flow path of the first evaporator 6a is set so that it does not become superheated steam. In order to evaporate non-evaporated water when the supply amount of water is large as described above, the second evaporation unit 6b is provided after the first evaporation unit 6a, and thus the first evaporation unit 6a has evaporated. When the water vapor flows into the second evaporator 6b, the water vapor is superheated by heating from the combustion gas flow path 5 to become superheated steam, and this superheated steam becomes a high temperature of about 300 ° C. In this way, the water vapor becomes high-temperature superheated steam in the second evaporator 6b and flows into the guide path 13 from the communication port 36, but directly flows into the guide path 13 through the communication port 36 from the first evaporator 6a. The steam having a temperature of about 100 ° C. and the superheated steam are mixed in the induction path 13 to be steam having an appropriate temperature of about 150 ° C. and pass through the opening 12. Here, when the temperature of the opening 12 constantly monitored by the temperature detection unit 17 exceeds 150 ° C., the control unit (not shown) controls the amount of combustion heat in the combustion unit 4, and the combustion gas flow path 5 Control is performed to lower the heating temperature of the second evaporation section 6b, and the temperature of the mixed gas of the raw material gas and water vapor that flows into the mixed gas flow path 14 through the opening 12 is maintained at about 150 ° C. .

  The raw material gas or water vapor that has flowed into the induction path 13 from the first evaporation section 6a or the second evaporation section 6b passes through the opening 12 and is sent to the mixed gas flow path 14 as a mixed gas. The mixed gas flowing in the mixed gas flow path 14 is heated by heat exchange with the reformed gas flowing in the reformed gas flow path 16, but is also heat exchanged with the gas in the induction path 13 through the partition wall 11 to supply water. When the amount is small, the temperature in the guiding path 13 is higher than usual, so the temperature of the mixed gas is slightly higher than usual, and is supplied to the reforming unit 8 as a mixed gas having a temperature of about 400 ° C. The When the temperature of the mixed gas supplied to the reforming unit 8 is about 400 ° C., the temperature of the reformed gas generated in the reforming unit 8 and exiting from the outlet 40 of the reforming unit 8 is about 450 ° C. When the reformed gas flows through the reformed gas channel 16, the temperature is lowered by the heat exchange with the mixed gas in the mixed gas channel 14 to reach a temperature of about 220 ° C., and the carbon monoxide removing unit 10 To be supplied.

  As described above, even if the amount of the raw material gas and the amount of water supplied to the preheating evaporation unit 6 fluctuate, the temperature of the mixed gas supplied to the reforming unit 8 is when the supply amount of water is the maximum amount. At about 350 ° C. and at a minimum amount of about 400 ° C., which can be maintained within a temperature range suitable for the steam reforming catalyst, and the reformed gas supplied to the carbon monoxide removal section 10 The temperature can be maintained within a temperature range suitable for the CO shift catalyst, such as about 200 ° C. when the supply amount of water is maximum and about 220 ° C. when the supply amount is minimum. Therefore, even if the amount of the raw material gas or the amount of water supplied to the preheating evaporation unit 6 fluctuates, the temperature of the reforming unit 8 and the carbon monoxide removal unit 10 is maintained appropriately, and is rich in hydrogen and carbon monoxide. The reformed gas from which the gas is removed can be stably produced. Since carbon monoxide can be stably removed from the reformed gas as described above, it is possible to prevent the fuel cell 18 from being deteriorated due to poisoning by carbon monoxide.

  FIG. 3 shows another embodiment of the present invention, in which a good heat conductor 15 is filled in the second evaporator 6b. In the case where the amount of water supplied to the preheating evaporator 6 is the maximum amount and unevaporated water stays in the second evaporator 6b, the water staying in the second evaporator 6b due to heat transfer from the combustion gas channel 5 is reduced. It is necessary to heat and evaporate, but by filling the second evaporator 6b with the good heat conductor 15 in this way, the water staying in the second evaporator 6b via the good heat conductor 15 can be obtained. Heat can be efficiently transferred and heated, and the evaporation efficiency of water in the second evaporation section 6b can be increased. As this good heat conductor 15, particles such as alumina having a higher thermal conductivity than water vapor can be used. In the embodiment of FIG. 3, in addition to the lower part of the second evaporator 6 b, The lower portion is also filled with particles of the good heat conductor 15.

It is a schematic sectional drawing which shows an example of embodiment of this invention. It is the schematic sectional drawing which expanded a part of the same as the above. It is a partially expanded schematic sectional drawing which shows an example of other embodiment of this invention. It is a schematic sectional drawing of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner cylinder 2 Outer cylinder 3 Cylinder 4 Combustion part 5 Combustion gas flow path 6 Preheating evaporation part 6a 1st evaporation part 6b 2nd evaporation part 7 Reforming catalyst 8 Reforming part 9 Carbon monoxide removal catalyst 10 Carbon monoxide removal Part 11 Partition 12 Opening part 13 Guidance path 14 Mixed gas flow path 15 Good heat conductor 16 Reformed gas flow path 17 Temperature detector 18 Fuel cell

Claims (7)

  A cylinder having an inner cylinder and an outer cylinder, a combustion gas flow path through which combustion gas generated along the inner circumference of the inner cylinder flows, and an inner cylinder between the inner cylinder and the outer cylinder Is disposed between the inner cylinder and the outer cylinder, and is reformed by supplying a raw material gas and water, evaporating water by heating from the combustion gas flow path, and heating the raw material gas A reformer that is formed with a catalyst and that undergoes a steam reforming reaction between the raw material gas supplied from the preheating evaporation unit and water vapor to produce a reformed gas containing hydrogen, and is disposed between the inner cylinder and the outer cylinder A hydrogen production apparatus comprising a carbon monoxide removal unit that is formed with a carbon monoxide removal catalyst and removes carbon monoxide in the reformed gas supplied from the reforming unit, the preheating evaporation unit A first evaporator disposed at a position where heat exchange is possible with the carbon monoxide remover, and a first evaporator And a second evaporating unit that is disposed below the first evaporating unit and evaporates water that has not been evaporated in the first evaporating unit, and includes a partition wall that surrounds the side and the lower portion of the second evaporating unit, and an upper portion of the partition wall An opening is formed, and a guide path is formed between the partition wall and the outer cylinder side of the second evaporator, where the water vapor evaporated in the first evaporator and the water vapor evaporated in the second evaporator merge. A hydrogen gas characterized in that a mixed gas flow path is formed between the reforming sections and supplied to the reforming section by circulating the raw material gas and the steam supplied from the preheating evaporation section through the induction path and passing through the opening. Manufacturing equipment.   The hydrogen production apparatus according to claim 1, wherein the preheating evaporation unit is formed as a spiral flow path that circulates along the inner cylinder.   The hydrogen production apparatus according to claim 1 or 2, wherein the second evaporation section is filled with a good heat conductor.   The reformed gas flow path for supplying the reformed gas generated in the reforming section and supplying it to the carbon monoxide removal section, and the mixed gas flow path are arranged at adjacent positions where heat exchange is possible. The hydrogen production apparatus according to any one of claims 1 to 3.   A temperature detector is provided in the opening, and the combustion of the combustion part is controlled while maintaining the temperature of the opening at a predetermined constant temperature, so that the non-evaporated water staying in the second evaporation part is evaporated. The hydrogen production apparatus according to any one of claims 1 to 4, wherein:   2. When water is heated and evaporated in the preheating evaporation unit, the water is sent from the first evaporation unit to the second evaporation unit in a two-phase flow of an aqueous phase and a gas phase. The hydrogen production apparatus in any one of thru | or 5.   A hydrogen production apparatus according to any one of claims 1 to 6, and a fuel cell that generates electricity using the reformed gas supplied from the hydrogen production apparatus and an oxidizing gas containing oxygen. A fuel cell power generator.

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