JP2007308318A - Reforming apparatus and its operation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reforming apparatus which has an enhanced heat-insulation performance of the fuel reforming section and can be built at a lower cost and in a smaller size and an operation method of the apparatus. <P>SOLUTION: The apparatus has the heat insulation material 4 surrounding the circumference of the fuel reforming section 2 and the water-cooling tube 5 spirally wound around the circumference of the cylinder 27 surrounding the circumference of the heat insulation material 4. The first raw material water 31 flowing in the water-cooling tube 5 is boiled by absorbing the heat from the fuel reforming section 2 (the reforming catalyst layer 18). This heat is transferred to the water-cooling tube 5 via the heat insulation material 4 from the inside of the heat insulation material 4 (the heat leaks from the heat insulation material 4). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a reformer that generates a reformed gas containing hydrogen gas by steam reforming a reformed fuel and an operation method thereof.

  The reformer generates a reformed gas containing hydrogen gas by steam reforming the reformed fuel, and this reformed gas is used as a fuel for a fuel cell. As a conventional example of such a reformer, for example, there are those disclosed in Patent Documents 1 to 3 below.

(1) Patent Documents 1, 2 and 4 disclose a reformer applied to a fuel cell with a power generation output of 5 kW class. In this reformer, a vacuum heat insulating container is used as a heat insulating means for the fuel reformer. Used.
(2) Patent Document 3 discloses a reformer applied to a fuel cell with a power generation output of 1 kW class. In this reformer, a vacuum heat insulating container is not used as a heat insulating means for a fuel reforming unit. Uses typical insulation.
(3) Further, in the reformer of Patent Document 3, the low temperature CO shift catalyst layer (LTS catalyst layer) is directly cooled with the raw material water, thereby using the heat generated in the LTS catalyst layer as the heat of evaporation of the raw material water. ing.
(4) Moreover, in the reformer of patent document 4, when using kerosene as a reformed fuel, a part of kerosene is evaporated using the combustion exhaust gas of a burner, and superheated steam is mixed with this kerosene. After the non-evaporated residual kerosene is completely evaporated, the mixed steam of kerosene and water vapor flows into the reforming catalyst layer.

JP 2003-327405 A Japanese Patent Laid-Open No. 2004-074435 JP 2004-123464 A JP 2005-108753 A

  However, the conventional reformer has the following problems.

(1) The vacuum heat insulation container used in the reformers of Patent Documents 1, 2, and 4 has high heat insulation performance, but is very expensive. For this reason, it is difficult to reduce the manufacturing cost of the reformer.
(2) On the other hand, the reforming apparatus of Patent Document 3 does not use a vacuum heat insulating container but uses a general heat insulating material, so that the manufacturing cost of the reforming apparatus can be reduced. However, since the configuration is such that the reforming catalyst layer at 700 ° C. is insulated only by the heat insulating material, if this configuration is used in a reformer applied to a fuel cell having a power generation output of 5 kW or more, for example, the heat insulating material Therefore, the proportion of the volume of the heat insulating material in the entire reforming apparatus is greatly increased, resulting in an increase in the size of the reforming apparatus.
(3) Moreover, in the reformer of patent document 3, since the LTS catalyst layer which operate | moves at 150 to 250 degreeC is cooled directly with boiling water, an LTS catalyst layer will become too cold. For this reason, it is necessary to supply the oxidation reaction heat of the CO selective oxidation part (PROX part) to the LTS catalyst layer to balance the temperature of both.
(4) In the reformer of Patent Document 4, kerosene is partially evaporated in advance with burner combustion exhaust gas having a temperature lower than the kerosene boiling point, and then mixed with superheated steam to completely evaporate. Therefore, it is necessary to control the temperature of the burner combustion exhaust gas, and since kerosene is a multi-component system, if it is heated below the boiling point, it will easily separate and cause evaporation vibrations, and the supply to the reforming catalyst layer will be uneven. turn into.

  Accordingly, in view of the above circumstances, the present invention can improve the heat insulation performance for the fuel reforming section, reduce the manufacturing cost of the reformer and reduce the size, and further prevent the LTS catalyst layer from being too cold. It is an object of the present invention to provide a reformer that does not require temperature control of burner combustion exhaust gas for boiling kerosene and that can uniformly supply reformed fuel to the fuel reforming section, and an operating method thereof. To do.

A reforming apparatus according to a first aspect of the present invention for solving the above-described problems is provided with a reforming catalyst layer of a fuel reforming section through which a mixed steam of reformed fuel and raw water flows, and an exhaust gas flow formed inside the fuel reforming section. In a reformer configured to generate a reformed gas containing hydrogen gas by steam reforming the reformed fuel by heating with a burner combustion exhaust gas flowing in a path,
A heat insulating material surrounding the fuel reforming section;
A water-cooled tube wound around an outer peripheral surface of a cylinder surrounding the periphery of the heat insulating material,
The raw water flowing through the water-cooled tube absorbs the heat of the fuel reforming portion transmitted from the inside of the heat insulating material to the water-cooled tube through the heat insulating material and boils.

The reformer of the second invention is the reformer of the first invention,
Having a mixing part for mixing the reformed fuel into the boiling raw material water discharged from the water-cooled tube;
A mixed fluid evaporating means for evaporating the mixed fluid of the raw material water and the reformed fuel discharged from the mixing unit;
A feature is that the vapor of the mixed fluid discharged from the mixed fluid evaporation means is supplied to the fuel reforming section.

The reformer of the third invention is the reformer of the second invention,
The mixed fluid evaporation means causes the mixed fluid of the raw material water and the reformed fuel to flow through a spiral tube provided in a double cylinder so that the inner wall surface of the double cylinder and the tube It is a mixed fluid evaporator configured to evaporate by heating with a burner combustion exhaust gas flowing through a gap therebetween.

The reformer of the fourth invention is the reformer of the third invention,
The mixed fluid evaporator is characterized in that the gap is filled with a heat transfer promoting material.

Further, the reformer of the fifth invention is the reformer of any of the first to fourth inventions,
A low-temperature CO conversion unit that CO converts the reformed gas generated in the fuel reforming unit, and is disposed so as to surround the water-cooled tube in a state where a gap is maintained between the reformed gas and the water-cooled tube. It has CO transformation part.

The reformer of the sixth invention is the reformer of the fifth invention,
The burner combustion exhaust gas is allowed to flow through the gap so that the low-temperature CO shift section can be heated.

The reformer of the seventh invention is the reformer of the sixth invention,
The burner combustion exhaust gas flowing through the gap heats the reforming catalyst layer in the fuel reforming section, and further heats the mixed fluid in the mixed fluid evaporator, so that the low temperature CO shift catalyst in the low temperature CO shift section The temperature is reduced to an intermediate temperature between the temperature of the layer and the wall temperature of the water-cooled tube and the cylinder, and is supplied to the gap.

Moreover, the reformer of the eighth invention is the reformer of any of the fifth to seventh inventions,
A high-temperature CO conversion section that CO converts the reformed gas generated in the fuel reforming section, and surrounds the periphery of the fuel reforming section, so that burner combustion exhaust gas passes through the fuel reforming section. It has a high-temperature CO transformation section that can be heated by
A feature is that the reformed gas discharged from the high temperature CO conversion section is supplied to the low temperature CO conversion section.

The reformer of the ninth invention is the reformer of the eighth invention,
The raw water is circulated through a spiral tube provided in the double cylinder, and the reformed gas from the high-temperature CO conversion section flows through the gap between the inner wall surface of the double cylinder and the tube. It has a raw material water evaporator configured to evaporate by heating,
The raw water vapor discharged from the raw water evaporator is supplied to the fuel reforming section, and the reformed gas discharged from the raw water evaporator is supplied to the low-temperature CO conversion section. Characterize.

The reformer of the tenth invention is the reformer of the ninth invention,
A cooling unit extending in the vertical direction along the side surface of the one or more CO selective oxidation catalyst layers arranged along the vertical direction, and supplying raw water from the lower end of the cooling unit to the inside of the cooling unit Having a CO selective oxidation part configured to cool the CO selective oxidation catalyst layer by circulating the gas upward,
The raw water discharged from the upper end of the cooling unit is supplied to the tube of the raw water evaporator.

The reformer of the eleventh invention is the reformer of the tenth invention.
The CO selective oxidation unit causes the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming unit to flow through the exhaust gas flow path provided along the side surface of the CO selective oxidation catalyst layer, thereby the CO selective oxidation unit. The selective oxidation catalyst layer can be heated.

The reformer of the twelfth invention is the reformer of the first invention,
The mixed fluid of reformed fuel and raw material water is circulated through a spiral tube provided in a double cylinder, and burner combustion exhaust gas flowing through the gap between the inner wall surface of the double cylinder and the tube Having a mixed fluid evaporator configured to evaporate by heating;
The mixed fluid vapor discharged from the mixed fluid evaporator is supplied to the fuel reforming unit.

The reformer of the thirteenth aspect of the invention is the reformer of the twelfth aspect of the invention,
The burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming section is configured to flow through the gap of the mixed fluid evaporator.

The reformer of the fourteenth invention is the reformer of the twelfth or thirteenth invention.
The mixed fluid evaporator is characterized in that the gap is filled with a heat transfer promoting material.

The reformer of the fifteenth aspect of the invention is the reformer of any of the twelfth to fourteenth aspects of the invention,
A low-temperature CO conversion unit that CO converts the reformed gas generated in the fuel reforming unit, and is disposed so as to surround the water-cooled tube in a state where a gap is maintained between the reformed gas and the water-cooled tube. It has CO transformation part.

Further, the reformer of the sixteenth invention is the reformer of the fifteenth invention,
The burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming section is caused to flow in the gap so that the low temperature CO shift section can be heated.

The reformer of the seventeenth invention is the reformer of the fifteenth or sixteenth invention,
A high-temperature CO conversion section that CO converts the reformed gas generated in the fuel reforming section, and surrounds the periphery of the fuel reforming section, so that burner combustion exhaust gas passes through the fuel reforming section. It has a high-temperature CO transformation section that can be heated by
A feature is that the reformed gas discharged from the high temperature CO conversion section is supplied to the low temperature CO conversion section.

The reformer of the eighteenth invention is the reformer of the seventeenth invention.
The high-temperature CO conversion that flows through the gap between the inner wall surface of the double cylinder and the tube by circulating the raw water discharged from the water-cooled tube through a spiral tube provided in the double cylinder. A raw material water evaporator configured to evaporate by heating with the reformed gas from the section;
The raw water vapor discharged from the raw water evaporator is supplied to the fuel reforming section, and the reformed gas discharged from the raw water evaporator is supplied to the low-temperature CO conversion section. Characterize.

The reformer of the nineteenth invention is the reformer of the eighteenth invention,
A cooling unit extending in the vertical direction along the side surface of the one or more CO selective oxidation catalyst layers arranged along the vertical direction, and supplying raw water from the lower end of the cooling unit to the inside of the cooling unit Having a CO selective oxidation part configured to cool the CO selective oxidation catalyst layer by circulating the gas upward,
The raw water discharged from the upper end of the cooling unit is configured to be supplied to the water cooling tube.

The reformer of the twentieth invention is the reformer of the nineteenth invention,
The CO selective oxidation unit causes the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming unit to flow through the exhaust gas flow path provided along the side surface of the CO selective oxidation catalyst layer, thereby the CO selective oxidation unit. The selective oxidation catalyst layer can be heated.

The reformer of the twenty-first invention is the reformer of the twentieth invention,
During preheating operation, burner combustion exhaust gas discharged from the gap between the water-cooled tube and the low-temperature CO conversion unit and burner combustion exhaust gas discharged from the exhaust gas flow path of the CO selective oxidation unit can be discharged. It is characterized by comprising a discharge switching means that enables the burner combustion exhaust gas discharged from the mixed fluid evaporator to be discharged during operation.

A reformer operating method according to a twenty-second aspect of the present invention is the reformer operating method according to the eleventh aspect of the present invention. During preheating operation, the burner is ignited to burn the burner combustion exhaust gas inside the fuel reforming section. The fuel reforming section is reformed by flowing through the exhaust gas passage formed in the gap, the gap between the low-temperature CO conversion section and the water cooling tube, and the exhaust gas passage of the CO selective oxidation section. Heating the catalyst layer, the high temperature CO conversion catalyst layer of the high temperature CO conversion section, the low temperature CO conversion catalyst layer of the low temperature CO conversion section and the CO selective oxidation catalyst layer of the CO selective oxidation section to a predetermined preheating temperature;
After this preheating operation, by starting the supply of raw water to the water cooling tube and the supply of reformed fuel to the mixing section, steam reforming of the reformed fuel in the fuel reforming section and the high temperature Starting CO conversion in the CO conversion section and the low temperature CO conversion section, and CO selective oxidation in the CO selective oxidation section, and simultaneously with the supply of the raw water to the water cooling tube or from the supply of the raw water The supply of raw material water to the cooling unit of the CO selective oxidation unit is also started later, so that the temperature of the CO selective oxidation catalyst layer of the CO selective oxidation unit and the reformed gas flowing into the low temperature CO conversion unit The temperature is set to a predetermined temperature.

Further, the reformer operating method of the twenty-third invention is the reformer operating method of the twenty-first invention, wherein during the preheating operation, the discharge switching means is connected between the water-cooled tube and the low-temperature CO conversion section. The burner combustion exhaust gas discharged from the gap and the burner combustion exhaust gas discharged from the exhaust gas flow path of the CO selective oxidation unit can be discharged, the burner is ignited, and the burner combustion exhaust gas is converted into the fuel reformer. The fuel reforming is performed by flowing through the exhaust gas passage formed inside the mass portion, the gap between the low temperature CO conversion portion and the water cooling tube, and the exhaust gas passage of the CO selective oxidation portion. The reforming catalyst layer of the part, the high temperature CO conversion catalyst layer of the high temperature CO conversion part, the low temperature CO conversion catalyst layer of the low temperature CO conversion part and the CO selective oxidation catalyst layer of the CO selective oxidation part are heated to a predetermined temperature. ,
After this preheating operation, the discharge switching means is switched to a state in which burner combustion exhaust gas discharged from the mixed fluid evaporator can be discharged, and the mixed fluid of the reformed fuel and the raw water to the mixed fluid evaporator By starting supply, steam reforming of the reformed fuel in the fuel reforming unit, CO conversion in the high temperature CO conversion unit and the low temperature CO conversion unit, and CO selective oxidation in the CO selective oxidation unit And starting the supply of raw water to the cooling section of the CO selective oxidation unit simultaneously with or behind the supply of the raw material water to the water cooling tube, The temperature of the CO selective oxidation catalyst layer of the CO selective oxidation unit and the temperature of the reformed gas flowing into the low temperature CO conversion unit are set to a predetermined temperature.

The reformer operating method of the twenty-fourth aspect of the invention is the reformer operating method of the twenty-second or twenty-third aspect of the invention,
During steady operation,
The maximum temperature of the reforming catalyst layer of the fuel reforming unit is measured, and the fuel supply amount to the burner is controlled so as to maintain this temperature measurement value within a predetermined temperature range,
In addition, the vapor temperature of the mixed fluid discharged from the mixed fluid evaporator and supplied to the fuel reforming unit is measured, and the temperature measurement value is maintained in a predetermined temperature range to the burner. It is characterized by controlling the air supply amount.

  According to the reforming apparatus of the first invention, the water-cooled tube wound around the outer peripheral surface of the cylinder surrounding the periphery of the heat insulating material, and the raw water flowing through the water-cooled tube is supplied with the heat insulating material from the inside of the heat insulating material. By absorbing the heat of the fuel reforming section transmitted to the water cooling tube through the water and boiling, the heat of the fuel reforming section leaked from the heat insulating material can be recovered as the evaporation heat of the raw material water by the water cooling tube Therefore, even if a heat insulating material that is inexpensive and has low heat insulating performance is used and the heat insulating material is thinned, the efficiency is not lowered due to an increase in the amount of heat radiation. For this reason, it is possible to reduce the manufacturing cost and size of the reformer.

  According to the reforming apparatus of the second invention, the reformed fuel is mixed into the raw water boiled in the water-cooled tube, so that, for example, when kerosene is used as the reformed fuel, the preliminary evaporation of kerosene is unnecessary and the kerosene boiling is not performed. The temperature of the burner combustion exhaust gas is not required, and the reformed fuel is mixed in the steam of the raw material water that has boiled and the flow velocity has increased (for example, 20 to 30 m / s). Even without using, the reformed fuel can be easily mixed with the raw water (steam) easily. Further, in the mixed fluid evaporation means, the reformed fuel evaporates together with the raw water (steam) (for example, the temperature rises to about 400 ° C.), so that the reformed fuel can be supplied uniformly to the fuel reforming section without causing evaporation oscillation. It can be performed and there is no carbon deposition.

  According to the reforming apparatus of the third invention, the mixed fluid evaporator as the mixed fluid evaporating means causes the mixed fluid of the raw water and the reformed fuel to flow through the spiral tube provided in the double cylinder. In addition, since it is configured to evaporate by heating with the burner combustion exhaust gas flowing in the gap between the inner wall surface of the double cylinder and the tube, the mixing is efficiently performed by effectively using the heat of the burner combustion exhaust gas. The fluid can be evaporated.

  According to the reforming apparatus of the fourth aspect of the invention, since the heat transfer promoting material is filled in the gap between the inner wall surface of the double cylinder and the tube, the heat of the burner combustion exhaust gas is directly from the burner combustion exhaust gas to the tube of the tube. Since the heat is not only transmitted to the wall but also transmitted to the tube wall of the tube through the heat transfer promoting material, the heat transfer of the burner combustion exhaust gas to the mixed fluid is promoted. Furthermore, the heat transfer facilitating material functions as a resistance for making the flow distribution of the burner combustion exhaust gas uniform, and the heat storage material that maintains the temperature of the mixed fluid even when the thermal balance between the mixed fluid and the burner combustion exhaust gas is lost. It can also serve as

  According to the reforming apparatus of the fifth aspect of the present invention, the gap between the low temperature CO conversion section and the water cooling tube is maintained, so that the raw water flowing through the water cooling tube passes through the gap at the low temperature of the low temperature CO conversion section. Since the CO shift catalyst layer is radiatively cooled, it is possible to prevent the low temperature CO shift catalyst layer from being overcooled and maintain the low temperature CO shift catalyst layer at a temperature suitable for the CO shift reaction (for example, around 200 ° C.). it can.

  According to the reforming apparatus of the sixth aspect of the invention, since the combustion of the burner combustion exhaust gas is allowed to flow through the gap between the low temperature CO conversion section and the water cooling tube, the low temperature CO conversion section can be heated. During operation, the heat of the burner combustion exhaust gas can be effectively used to preheat the low temperature CO conversion catalyst layer in the low temperature CO conversion section.

  According to the reforming apparatus of the seventh invention, the burner combustion exhaust gas flowing through the gap between the low-temperature CO conversion section and the water-cooled tube heats the reforming catalyst layer in the fuel reforming section, and further in the mixed fluid evaporator By heating the mixed fluid, the temperature is reduced to an intermediate temperature between the temperature of the low-temperature CO conversion catalyst layer of the low-temperature CO conversion unit and the wall temperature of the water-cooled tube and the cylinder, and is supplied to the gap. Burner combustion exhaust gas relaxes the decrease in temperature on the upstream side in the reformed gas flow direction of the low-temperature CO conversion catalyst layer, in particular, from the upstream (high-temperature part) in the reformed gas flow direction in the low-temperature CO conversion catalyst layer (low temperature). Part) can be brought close to an ideal linear change.

  According to the reforming apparatus of the eighth aspect of the invention, the high temperature CO conversion section is arranged so as to surround the fuel reforming section, so that it can be heated by the burner combustion exhaust gas through the fuel reforming section. At start-up (during preheating operation), the reforming catalyst layer in the fuel reforming section is preheated with burner combustion exhaust gas, and at the same time, the high temperature CO conversion catalyst layer in the high temperature CO conversion section can be preheated. That is, it is possible to easily preheat the high temperature CO conversion catalyst layer in the high temperature CO conversion section with a simple configuration.

  According to the reforming apparatus of the ninth aspect of the invention, the raw water is circulated through the spiral tube provided in the double cylinder, and flows through the gap between the inner wall surface of the double cylinder and the tube. Since it has the raw material water evaporator of the structure evaporated by heating with the reformed gas from a high temperature CO conversion part, raw material water can be efficiently evaporated using the heat | fever of reformed gas effectively. That is, the heating (evaporation) of the raw material water and the temperature reduction of the reformed gas can be performed efficiently.

  According to the reforming apparatus of the tenth aspect of the invention, the CO selective oxidation unit includes the cooling unit that extends in the vertical direction along the side surface of the one or plural CO selective oxidation catalyst layers arranged along the vertical direction. The raw material water is supplied from the upper end of the cooling unit by supplying the raw water from the lower end of the cooling unit and circulating the inside of the cooling unit to cool the CO selective oxidation catalyst layer. Compared with the case where it distribute | circulates below, whole raw material water in a cooling part can be easily made into boiling temperature (for example, 100 degreeC). That is, when the raw water is supplied from the upper end of the cooling unit, the boiling raw material water does not flow downward easily, but only the cold raw water flows first downward. Although it is difficult to achieve a uniform boiling temperature, when the raw material water is supplied from the lower end of the cooling unit, the boiling raw material water immediately flows upward, so the entire raw material water in the cooling unit is easily boiled uniformly. Can be temperature. For this reason, the temperature of the entire CO selective oxidation catalyst layer can be easily set to a temperature suitable for the CO selective oxidation reaction.

  According to the reforming apparatus of the eleventh aspect of the invention, the CO selective oxidation unit is configured to provide an exhaust gas flow in which the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming unit is provided along the side surface of the CO selective oxidation catalyst layer. Since the CO selective oxidation catalyst layer can be heated by flowing it through the channel, the heat of the burner combustion exhaust gas is effectively used at the time of start-up (during preheating operation), and CO selective oxidation in the CO selective oxidation unit is performed. The catalyst layer can be preheated.

  According to the reformer of the twelfth aspect of the invention, the mixed fluid of reformed fuel and raw material water is circulated in a spiral tube provided in the double cylinder, and the inner wall surface of the double cylinder and the tube Since the mixed fluid evaporator is configured to evaporate by heating with the burner combustion exhaust gas flowing through the gap between the two, the heat of the burner combustion exhaust gas can be effectively used to efficiently evaporate the mixed fluid. .

  According to the reforming apparatus of the thirteenth aspect of the invention, since the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming section is configured to flow in the gap of the mixed fluid evaporator, the burner after heating the reforming catalyst layer The mixed fluid can be evaporated by effectively using the heat of the combustion exhaust gas.

  According to the reforming apparatus of the fourteenth aspect of the invention, since the heat transfer promoting material is filled in the gap between the inner wall surface of the double cylinder and the tube, the heat of the burner combustion exhaust gas is directly transferred from the burner combustion exhaust gas to the tube of the tube. Since the heat is not only transmitted to the wall but also transmitted to the tube wall of the tube through the heat transfer promoting material, the heat transfer of the burner combustion exhaust gas to the mixed fluid is promoted. Furthermore, the heat transfer facilitating material functions as a resistance for making the flow distribution of the burner combustion exhaust gas uniform, and the heat storage material that maintains the temperature of the mixed fluid even when the thermal balance between the mixed fluid and the burner combustion exhaust gas is lost. It can also serve as

  According to the reforming apparatus of the fifteenth aspect of the present invention, the gap between the low temperature CO conversion section and the water cooling tube is maintained, so that the raw water flowing through the water cooling tube passes through the gap at the low temperature of the low temperature CO conversion section. Since the CO shift catalyst layer is radiatively cooled, it is possible to prevent the low temperature CO shift catalyst layer from being overcooled and maintain the low temperature CO shift catalyst layer at a temperature suitable for the CO shift reaction (for example, around 200 ° C.). it can.

  According to the reforming apparatus of the sixteenth aspect of the present invention, the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming section is caused to flow in the gap between the low temperature CO conversion section and the water cooling tube, thereby the low temperature CO conversion section. Therefore, the heat of the burner combustion exhaust gas can be effectively used at the time of start-up (during preheating operation) to preheat the low temperature CO shift catalyst layer of the low temperature CO shift section.

  According to the reforming apparatus of the seventeenth aspect of the present invention, the high-temperature CO conversion section is arranged so as to surround the fuel reforming section, so that it can be heated by the burner combustion exhaust gas through the fuel reforming section. At start-up (during preheating operation), the reforming catalyst layer in the fuel reforming section is preheated with burner combustion exhaust gas, and at the same time, the high temperature CO conversion catalyst layer in the high temperature CO conversion section can be preheated. That is, it is possible to easily preheat the high temperature CO conversion catalyst layer in the high temperature CO conversion section with a simple configuration.

  According to the reforming apparatus of the eighteenth aspect of the invention, the raw water discharged from the water-cooled tube is circulated through the spiral tube provided in the double cylinder, and the inner wall surface of the double cylinder and the tube Since it has a raw material water evaporator configured to evaporate by heating with the reformed gas from the high-temperature CO conversion section flowing through the gap between the two, the raw material water is efficiently evaporated by effectively using the heat of the reformed gas Can be made. That is, the heating (evaporation) of the raw material water and the temperature reduction of the reformed gas can be performed efficiently.

  According to the reforming apparatus of the nineteenth aspect of the invention, the CO selective oxidation unit includes the cooling unit extending in the vertical direction along the side surface of the one or plural CO selective oxidation catalyst layers arranged along the vertical direction. The raw material water is supplied from the upper end of the cooling unit by supplying the raw water from the lower end of the cooling unit and circulating the inside of the cooling unit to cool the CO selective oxidation catalyst layer. Compared with the case where it distribute | circulates below, whole raw material water in a cooling part can be easily made into boiling temperature (for example, 100 degreeC). That is, when the raw water is supplied from the upper end of the cooling unit, the boiling raw material water does not flow downward easily, but only the cold raw water flows first downward. Although it is difficult to achieve a uniform boiling temperature, when the raw material water is supplied from the lower end of the cooling unit, the boiling raw material water immediately flows upward, so the entire raw material water in the cooling unit is easily boiled uniformly. Can be temperature. For this reason, the temperature of the entire CO selective oxidation catalyst layer can be easily set to a temperature suitable for the CO selective oxidation reaction.

  According to the reforming apparatus of the twentieth aspect of the invention, the CO selective oxidation unit is configured to provide an exhaust gas flow in which the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming unit is provided along the side surface of the CO selective oxidation catalyst layer. Since the CO selective oxidation catalyst layer can be heated by flowing it through the channel, the heat of the burner combustion exhaust gas is effectively used at the time of start-up (during preheating operation), and CO selective oxidation in the CO selective oxidation unit is performed. The catalyst layer can be preheated.

  According to the reforming apparatus of the twenty-first aspect of the invention, the exhaust gas switching unit causes the burner combustion exhaust gas to flow through the exhaust gas passage of the CO selective oxidation unit only during the preheating operation at the time of startup, and the exhaust gas flow passage of the CO selective oxidation unit during steady operation. Since the burner combustion exhaust gas can be prevented from flowing into the CO, the heat generated in the CO selective oxidation unit can be used for evaporation of the raw material water flowing in the cooling unit without being discharged together with the burner combustion exhaust gas. Even when the burner combustion exhaust gas is caused to flow through the exhaust gas passage of the CO selective oxidation unit, the heat dissipation loss can be reduced.

  According to the operation method of the reforming apparatus of the twenty-second aspect of the invention, the catalyst layers of the fuel reforming section, the high temperature CO conversion section, the low temperature CO conversion section, and the CO selective oxidation section are efficiently used by the burner combustion exhaust gas during the preheating operation at the time of startup. After the preheating operation (after each catalyst layer reaches a predetermined preheating temperature), the raw water is supplied to the water cooling tube, the reformed fuel is supplied to the mixing unit, and the cooling unit of the CO selective oxidation unit The generation of the reformed gas can be started by starting the supply of the raw material water.

  According to the operation method of the reforming apparatus of the twenty-third aspect of the invention, the exhaust gas switching means causes the burner combustion exhaust gas to flow through the exhaust gas passage of the CO selective oxidation unit only during the preheating operation at startup, and the CO selective oxidation unit during steady operation. In order to prevent the burner combustion exhaust gas from flowing through the exhaust gas flow path, the heat generated in the CO selective oxidation section can be used for evaporation of the raw material water flowing through the cooling section without being discharged together with the burner combustion exhaust gas, so that steady operation is possible. Sometimes the heat dissipation loss can be reduced compared with the case where the burner combustion exhaust gas is passed through the exhaust gas passage of the CO selective oxidation section, and the raw material after the preheating operation (after each catalyst layer reaches a predetermined preheating temperature) The generation of the reformed gas can be started by starting the supply of the mixed fluid of water and reformed fuel to the mixed fluid evaporator and the supply of the raw water to the cooling unit of the CO selective oxidation unit.

  According to the operation method of the reforming apparatus of the twenty-fourth aspect of the invention, during the steady operation, the maximum temperature of the reforming catalyst layer of the fuel reforming unit is measured, and this temperature measurement value is maintained within a predetermined temperature range. The fuel supply amount to the burner is controlled, and the vapor temperature of the mixed fluid discharged from the mixed fluid evaporator and supplied to the fuel reforming unit is measured, and this temperature measurement value is maintained within a predetermined temperature range. Thus, since the air supply amount to the burner is controlled, the maximum temperature of the reforming catalyst layer and the vapor temperature of the mixed fluid can be reliably maintained within respective predetermined temperature ranges.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

<Embodiment 1>
1 is a cross-sectional view showing a configuration of a main body portion of a reformer according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view showing a configuration of a CO selective oxidation unit of the reformer, and FIG. 4 is a cross-sectional view taken along line BB in FIG. 1, FIG. 5 is a cross-sectional view taken along line CC in FIG. 1, and FIG. 6 is a DD line in FIG. FIG. 7 is an enlarged cross-sectional view of a portion E in FIG. FIG. 8 is a block diagram of a temperature control system provided in the reformer, and FIG. 9 is an explanatory diagram showing a temperature gradient of the low temperature CO shift catalyst layer.

  As shown in FIGS. 1 and 2, the reformer of the first embodiment includes a reformer main body 100 and a CO selective oxidation unit 101 (hereinafter referred to as a PROX unit).

  As shown in FIGS. 1 and 3 to 5, the reformer main body 100 has a fuel combustion part 1 of a burner 11 at the center. Under the reformer main body 100, the fuel reformer 2, the high-temperature CO converter 3 (hereinafter referred to as the HTS part), the heat insulating material 4, the water-cooled tube 5, and the low-temperature CO converter, centering on the burner 11. The part 6 (hereinafter referred to as the LTS part), the heat insulating material 7 and the like are disposed concentrically, and on the upper side of the reformer main body 100, the heat insulating material 19 and the mixed fluid evaporator ( A first evaporator 8 as a mixed fluid evaporation means), a heat insulating material 9, a second evaporator 10 as a raw water evaporator, a heat insulating material 7 and the like are arranged concentrically.

  More specifically, a vertical pipe 13 made of metal such as stainless steel is disposed at the center of the reformer main body 100, and the inside of the vertical pipe 13 serves as the fuel combustion unit 1. The vertical pipe 13 has an upper end closed by an end plate 14 and a lower end having an opening 15. The vertical tube 13 has a larger diameter on the upper side than on the lower side. The burner 11 is inserted into the center of the vertical pipe 13 and is located above the fuel combustion unit 1. Therefore, when the fuel 109 and the air 110 are supplied to the burner 11 from above the burner 11 and the burner 11 is ignited, the fuel injected from the burner 11 is burned in the fuel combustion section 1 and the flame 12 extends downward. The fuel combustion section 1 (vertical pipe 13) holds a high-temperature (for example, about 1000 ° C.) combustion exhaust gas (hereinafter referred to as burner combustion exhaust gas) generated by the combustion of the burner 11 at this time, and keeps the lower end of the combustion combustion section 1 (vertical pipe 13). It can be discharged from the opening 15.

  Then, on the lower side of the reformer main body 100, the fuel reformer 2 is disposed concentrically with the fuel combustor 1 (vertical tube 13) so as to surround the fuel combustor 1 (vertical tube 13). ing. The fuel reforming unit 2 is a part that generates reformed gas containing hydrogen gas by steam reforming reformed fuel such as kerosene in the presence of a reforming catalyst. More specifically, the fuel reforming section 2 includes a reforming catalyst layer 18 formed by filling a reforming catalyst having a diameter of, for example, 3 mm between an inner cylinder 16 and an outer cylinder 17 made of metal such as stainless steel constituting a double cylinder. It is of a housed configuration and surrounds the periphery of the vertical pipe 13 with an appropriate gap from the vertical pipe 13 so that a cylindrical exhaust gas flow path 20 is formed between the vertical pipe 13 and the vertical pipe 13. It is arranged concentrically with the fuel combustion section 1 (vertical pipe 13).

  Therefore, in the fuel reforming unit 2, the steam of the mixed fluid of the reformed fuel and the raw water supplied from the upper end of the first evaporator 8 and the second evaporator 10 (detailed later) and the raw water steam are supplied. However, after being discharged downward from the lower end of the reforming catalyst layer 18 while flowing down the reforming catalyst layer 18 of the fuel reforming portion 2, the fuel reforming portion 1 is discharged downward from the opening 15 at the lower end. Steam reforming of the reformed fuel is performed by indirect countercurrent contact with the high-temperature burner combustion exhaust gas flowing in the exhaust gas flow path 20 and rising in the exhaust gas flow path 20 through the inner cylinder 16. It is possible to receive the heat required for the burner combustion exhaust gas.

  In addition, a cylinder 21 made of metal such as stainless steel is disposed around the fuel reforming section 2 concentrically with the fuel reforming section 2 with an appropriate distance from the outer cylinder 17 of the fuel reforming section 2. Has been. The outer cylinder 17 of the fuel reforming section 2 is a cylinder having a constant diameter, while the cylinder 21 has a larger diameter on the upper side than on the lower side. For this reason, the width of the gap between the outer cylinder 17 and the cylinder 21 is larger on the upper side than on the lower side. The lower portion of the gap between the outer cylinder 17 and the cylinder 21 is a reformed gas reversal rising portion 22, and the lower end of the reformed gas reversal rising portion 22 communicates with the lower end of the fuel reforming portion 2. is doing. Further, the lower end of the inner cylinder 16 and the lower end of the cylinder 21 of the fuel reforming section 2 are closed by an annular end plate 23. Therefore, the reformed gas discharged downward from the fuel reforming unit 2 (reforming catalyst layer 18) is reversed and flows into the reformed gas reversing and rising unit 22, It can flow upwards.

On the other hand, the upper portion of the gap between the outer cylinder 17 and the cylinder 21 accommodates a high temperature CO conversion catalyst layer 24 (hereinafter referred to as an HTS catalyst layer) filled with a granular high temperature CO conversion catalyst (HTS catalyst). Thus, the HTS unit 3 is configured. That is, the HTS unit 3 is cylindrical and is disposed concentrically with the fuel reforming unit 2 so as to surround the fuel reforming unit 2. Since the HTS unit 3 communicates with the reformed gas reversal raising unit 22, the reformed gas that has risen in the reformed gas reversal raising unit 22 flows into the HTS unit 3 and enters the HTS unit 3 (HTS Flows upward in the catalyst 24). At this time, the HTS unit 3 converts the reformed gases CO and H ₂ O into CO ₂ and H ₂ . Note that the reformed gas that rises in the reformed gas reversal riser 22 and travels toward the HTS unit 3 is a gas that descends in the fuel reformer 2 (mixed steam or reformed gas of reformed fuel and steam). Since the counter-current contact is indirectly made through the outer cylinder 17 of the fuel reforming section 2, heat is applied to the gas descending in the fuel reforming section 2, and it is suitable for CO conversion in the HTS section 3 itself. The temperature is decreased. That is, the reformed gas reversal raising unit 22 also functions as a heat exchange unit.

  Further, a horizontal annular plate 25 is coupled to the outer peripheral surface of the inner cylinder 16 of the fuel reforming unit 2, and the upper end of the outer cylinder 17 of the fuel reforming unit 2 and the cylinder 21 are connected to the lower surface of the horizontal annular plate 25. The upper end is connected. That is, the upper end surfaces of the fuel reforming unit 2 and the HTS unit 3 are closed by the horizontal annular plate 25. However, the horizontal annular plate 25 is provided with a plurality of small holes 25a for supplying the mixed steam to the fuel reforming section 2, and for discharging the reformed gas to the HTS section 3. A plurality of small holes 25b are opened. Note that the HTS unit 3 is not necessarily provided when the CO transformation can be sufficiently performed only by the LTS unit 6. In this case, the HTS catalyst layer 24 is not provided in the upper portion of the gap between the outer cylinder 17 and the cylinder 21, and the reformed gas reversal rising portion 22 extends from the bottom to the top of the gap.

  The heat insulating material 4 is cylindrical and is arranged concentrically with the fuel reforming unit 2 so as to surround the fuel reforming unit 2. In the illustrated example, since the HTS unit 3 is provided, the heat insulating material 4 is disposed so as to be concentric with the HTS unit 3 so as to surround the fuel reforming unit 2. More specifically, the fuel reforming section 2 (HTS section 3) is configured such that the inner cylinder 26 and the outer cylinder 27 made of metal such as stainless steel constituting the double cylinder surround the periphery of the fuel reforming section 2 (HTS section 3). A heat insulating material 4 such as a ceramic fiber is provided between the inner cylinder 26 and the outer cylinder 27. The upper ends of the inner cylinder 26 and the outer cylinder 27 are coupled to the lower surface of the horizontal annular plate 25.

  On the other hand, the lower end surface of the inner cylinder 26 is closed by an end plate 28, and the lower end surface of the outer cylinder 27 is closed by an end plate 29. Between the end plate 28 and the end plate 29, a ceramic fiber or the like is provided. A horizontal disk-shaped heat insulating material 30 is provided. These heat insulating materials 4 and 30 are for preventing the heat of the fuel reforming section 2 (the reforming catalyst layer 18) from leaking (dissipating heat) to the outside of the reforming apparatus. Note that a space with an appropriate vertical width is formed between the upper surface (end plate 28) of the heat insulating material 30 and the lower end (opening 15) of the vertical tube 13, and this is an extension of the vertical tube 13 due to thermal expansion. This is for securing white (about 10 mm).

  On the other hand, on the upper side of the reformer main body 100, a cylindrical heat insulating material 19 such as a ceramic fiber is disposed concentrically with the vertical pipe 13 so as to surround the vertical pipe 13. The first evaporator 8 has a function of heating and evaporating the mixed fluid of the reformed fuel and the raw water by recovering the heat of the burner combustion exhaust gas. The first evaporator 8 has a cylindrical shape provided with a spiral tube 34 and is arranged concentrically with the heat insulating material 19 so as to surround the heat insulating material 19. As reformed fuel, gaseous fuel such as methane gas or liquid fuel such as kerosene is used. When liquid fuel is used as the reformed fuel, the liquid fuel is also evaporated by the heat of the burner combustion exhaust gas in the first evaporator 8.

  Referring to FIGS. 1 and 7, the first evaporator 8 has a spiral shape made of metal such as stainless steel between an inner cylinder 32 made of metal such as stainless steel and an outer cylinder 33 constituting a double cylinder. A tube 34 (for example, a tube having an outer diameter of 8 mm and a wall thickness of 1 mm) is provided, and a gap 8 a between the spiral tube 34 and the inner cylinder 32 and a gap 8 b between the spiral tube 34 and the outer cylinder 33 are provided. Each is configured to be filled with a ceramic or stainless steel ball 35 (for example, 5 mm in diameter) as a heat transfer promoting material.

  A cylinder 38 made of a punching metal (perforated plate) is provided between the inner cylinder 32 and the outer cylinder 33, and a helical tube 34 is fixed to the outer peripheral surface of the cylinder 38 by welding or the like. . The upper end surface between the inner cylinder 32 and the outer cylinder 33 of the first evaporator 8 is closed by an annular end plate 39, and the outer peripheral edge of the annular end plate 40 is coupled to the lower end of the outer cylinder 33. The upper end of the inner cylinder 16 of the fuel reforming section 2 is coupled to the inner peripheral edge of the end plate 40. The upper end and the lower end of the cylinder 38 are fixed to the end plate 39 and the end plate 40 by welding or the like, respectively. Further, annular perforated plates (punching metal) 36 a and 36 b for supporting the ball 35 are fixed to the upper and lower sides of the outer peripheral surface of the inner cylinder 32 by welding or the like. On both the upper and lower sides, annular perforated plates (punching plates) 37a and 37b for supporting the balls 35 are fixed by welding or the like.

  It is difficult to manufacture the spiral tube 34 with good dimensional accuracy of the inner diameter and the outer diameter, and the inner side and the outer side of the spiral tube 34 are simply fixed to the end plates 39, 40, the outer cylinder 33, and the like. Although it is difficult to ensure the gaps 8a and 8b for filling the balls 35 to each other, if the cylinder 38 is used and the spiral tube 34 is fixed to the outer peripheral surface of the cylinder 38 as described above, The gaps 8a and 8b can be easily and reliably secured inside and outside the spiral tube 34. In this case, the spiral tube 34 is not limited to the outer peripheral surface of the cylinder 38 and may be fixed to the inner peripheral surface of the cylinder 38.

  A plurality of holes 41 are formed in the lower end portion of the inner cylinder 32, and the gaps 8 a and 8 b in the first evaporator 8 and the exhaust gas flow channel 20 communicate with each other through the holes 41. On the other hand, an exhaust gas tube 42 is connected to the upper end of the first evaporator 8, and the exhaust gas tube 42 communicates with the gaps 8 a and 8 b in the first evaporator 8. The exhaust gas tube 42 is branched into an exhaust gas tube 43 extending downward inside the heat insulating material 7 and an exhaust gas tube 44 extending outward of the heat insulating material 7.

  Therefore, the burner combustion exhaust gas that has risen in the exhaust gas passage 20 flows into the first evaporator 8 through the hole 41 and flows upward through the gaps 8a and 8b in the first evaporator 8, It is discharged to the exhaust gas tube 42 and distributed to the exhaust gas tube 43 and the exhaust gas tube 44. On the other hand, the spiral tube 34 has an upper end inlet 34a connected to the mixing unit 46 via a metal tube 45 such as stainless steel, and a lower end outlet 34b connected to the mixer tube 48 via a metal tube 47 such as stainless steel. It is connected. Therefore, the mixed fluid of the reformed fuel and the raw water supplied from the mixing unit 46 via the tube 45 flows into the spiral tube 34 from the upper end inlet 34a and flows downward in the spiral tube 34. Thereafter, the gas is discharged out of the spiral tube 34 from the outlet 34b at the lower end, and flows to the mixer tube 48 via the tube 47 (for example, an outer diameter of 12 mm and a wall thickness of 1 mm).

  For this reason, in the first evaporator 8, the mixed fluid flowing in the spiral tube 34 and the burner combustion exhaust gas flowing outside the spiral tube 34 are indirectly in countercurrent contact via the tube wall of the spiral tube 34. It will be. Moreover, since the burner combustion exhaust gas flows so as to pass between the balls 35 at this time, the heat of the burner combustion exhaust gas is not only directly transmitted from the burner combustion exhaust gas to the tube wall of the spiral tube 34 but also via the balls 35. Is also transmitted to the tube wall of the spiral tube 34. That is, the ball 35 functions as a heat transfer promoting material for promoting heat transfer from the burner combustion exhaust gas to the spiral tube 34. Further, the ball 35 functions as a resistor for making the flow distribution of the burner combustion exhaust gas uniform, and when the heat balance between the mixed fluid and the burner combustion exhaust gas is lost due to load fluctuations of the fuel cell, etc. It also functions as a heat storage material that maintains temperature. In addition, the ball 35 has one layer on each of the inner side and the outer side of the spiral tube 34, thereby reducing pressure loss when the burner combustion exhaust gas passes between the balls 35, and more than necessary due to the multilayering of the balls 35. This prevents an increase in the heat capacity. When the heat capacity increases, the temperature rise of the LTS unit 6 and the PROX unit 101 due to burner combustion exhaust gas at the time of start-up (preheating operation) described later is delayed.

  The heat insulating material 9 has a cylindrical shape made of a ceramic fiber or the like, and is arranged concentrically with the first evaporator 8 so as to surround the first evaporator 8. The second evaporator 10 is disposed concentrically with the first evaporator 8 around the first evaporator 8 via a heat insulating material 19. More specifically, the second evaporator 10 includes a spiral tube 51 made of metal such as stainless steel (for example, an outer diameter of 8 mm, between an inner cylinder 49 made of stainless steel or the like and an outer cylinder 50 constituting a double cylinder. A tube having a wall thickness of 1 mm is provided. The spiral tube 51 is spirally wound around the outer peripheral surface of the inner cylinder 49 and has a gap 10 a serving as a gas flow path between the spiral tube 51 and the outer cylinder 50. In addition, although illustration is abbreviate | omitted, in order to ensure the space | gap 10a between the spiral tube 51 and the outer cylinder 50 reliably, for example, several wires (for example, diameter 2mm) are used for the spiral tube 51 and the outer cylinder. It is desirable to insert it between 50 and the vertical direction. An upper end surface and a lower end surface between the inner cylinder 49 and the outer cylinder 50 are closed by annular end plates 54 and 55.

  And the upper end part of the 2nd evaporator 10 is connected to the LTS part 6 via metal tubes 52, such as stainless steel, and the tube 52 and the clearance gap 10a in the 2nd evaporator 10 are connected. Further, the lower end portion of the second evaporator 10 is connected to the HTS portion 3 via a metal tube 53 such as stainless steel, and the tube 53 and the gap 10 a in the second evaporator 10 communicate with each other. Therefore, the reformed gas from the HTS unit 3 flows into the second evaporator 10 from the lower end of the second evaporator 10 via the tube 53 and flows upward through the gap 10a in the second evaporator 10. After that, it is discharged from the upper end of the second evaporator 10 and flows to the LTS unit 6 through the tube 52. On the other hand, the spiral tube 51 has an upper end inlet 51a connected to the PROX portion 101 via a metal tube 56 such as stainless steel (details will be described later), and a lower end outlet 51b made of a metal tube 57 such as stainless steel (for example, an outer tube). And a mixer tube 48 via a diameter of 8 mm and a thickness of 1 mm.

  Accordingly, the raw water from the PROX unit 101 flows into the spiral tube 51 from the upper end inlet 51a, flows downward in the spiral tube 51, and then is discharged out of the spiral tube 51 from the lower end outlet 51b. And flows to the mixer tube 48 via the tube 57. Therefore, in the second evaporator 10, the reformed gas from the HTS unit 3 and the raw water from the PROX unit 101 are in countercurrent contact via the tube wall of the spiral tube 51, and the reformed gas has. By recovering the heat with the raw water, the temperature of the reformed gas is reduced from 450 ° C. to 250 ° C., for example, while the raw water is evaporated.

  It should be noted that the second evaporator 10 does not employ a ball (heat transfer facilitating material) and employs only the gap 10a of the gas flow path because the reformed gas from the HTS unit 3 is five times as much as air. This is because it has a near thermal conductivity, and therefore there is a low need for heat transfer by a ball or the like.

  The mixer tube 48 is a tube made of metal such as stainless steel (for example, an outer diameter of 12 mm and a wall thickness of 1 mm), and is disposed below the first evaporator 8 and the second evaporator 10 and above the horizontal annular plate 25. . The mixer tube 48 generates steam (mixed steam of reformed fuel and raw water) from the spiral tube 34 of the first evaporator 8 and steam (raw water steam) from the spiral tube 51 of the second evaporator 10. The mixture is mixed and supplied to the fuel reforming unit 2.

  A header 58 is provided on the fuel reforming unit 2. The header 58 has an annular shape, and has an inner peripheral surface coupled to the outer peripheral surface of the inner cylinder 16 of the fuel reforming unit 2 and a lower surface coupled to the horizontal annular plate 25. The header 58 and the mixer tube 48 are connected via metal tubes 59 and 60 (for example, a diameter of 8 mm and a wall thickness of 1 mm) such as stainless steel. The tubes 59 and 60 are connected to point-symmetrical positions in the circumferential direction of the header 58. Therefore, the mixed steam discharged from the mixer tube 48 is once divided into two by the tubes 59, 60, flows into the header 58 from the circumferential point symmetrical position of the header 58, and is distributed in the circumferential direction. Through the 25 small holes 25a, the fuel is uniformly distributed and supplied into the fuel reforming section 2 in the circumferential direction.

On the other hand, on the lower side of the reformer main body 100, the LTS unit 6 is disposed concentrically with the heat insulating material 4 (outer cylinder 27) so as to surround the heat insulating material 4 (outer cylinder 27). The LTS unit 6 has a function of shifting the composition of the reformed gas cooled by the second evaporator 10 to the side where H ₂ is increased by CO conversion. More specifically, the LTS unit 6 includes a low temperature CO shift catalyst layer 64 in which a low temperature CO shift catalyst (LTS catalyst) is filled between an inner cylinder 61 and an outer cylinder 62 made of metal such as stainless steel constituting a double cylinder. (Hereinafter referred to as an LTS catalyst layer). The upper end surface between the inner cylinder 61 and the outer cylinder 62 is closed by a horizontal annular plate 25, and the lower end surface is closed by an annular end plate 65. The lower end surface of the outer cylinder 62 is closed by the end plate 29. In addition, the inlet 6 a at the upper end of the LTS unit 6 is connected to the outlet side of the second evaporator 10 via the tube 52, and the outlet 6 b at the lower end of the LTS unit 6 is connected to the PROX unit 101 via the tube 71. (Details will be described later). Therefore, the reformed gas discharged from the second evaporator 10 flows into the LTS unit 6 from the upper inlet 6a via the tube 52, and flows downward in the LTS unit 6 (in the LTS catalyst layer 64). After that, it is discharged from the outlet 6 b at the lower end and flows to the PROX unit 101 via the tube 71. At this time, the LTS unit 6 transforms the reformed gases CO and H ₂ O into CO ₂ and H ₂ .

  And in order to remove the heat | fever accompanying CO transformation in the LTS part 6 at this time, between the LTS part 6 (inner cylinder 61) and the outer cylinder 27 surrounding the heat insulating material 4, the LTS cooling space part 63 is provided. A gap having an appropriate width is provided, and the water cooling tube 5 is provided in the LTS cooling space 63.

  The water-cooled tube 5 is a tube made of metal such as stainless steel (for example, an outer diameter of 7 mm and a wall thickness of 1 mm), and is spirally wound around the outer peripheral surface of an outer cylinder 27 surrounding the heat insulating material 4. Moreover, a gap 66 of an appropriate distance is secured between the water cooling tube 5 and the LTS portion 6 (inner cylinder 61). That is, the water cooling tube 5 is not in contact with the LTS part 6 (inner cylinder 61). An inlet 5 a at the lower end of the water cooling tube 5 is connected to a raw water supply device such as a pump (not shown), and an outlet 5 b at the upper end of the water cooling tube 5 is connected to the mixing unit 46 via a tube 68.

  Accordingly, the first raw water 31 supplied from the raw water supply device flows into the water-cooled tube 5 from the lower end inlet 5a, flows upward in the water-cooled tube 5, and then discharged from the upper end outlet 5b. , Flows to the first evaporator 8 through the tube 68, the mixing unit 46 and the tube 45. In addition, the 1st raw material water 31 is one raw material water which distributed the raw material water sent from the said raw material water supply apparatus into 2 parts. Then, the first raw material water 31 is transmitted (leaked) from the inside of the heat insulating material 4 through the heat insulating material 4 while flowing through the water-cooled tube 5, and the heat of the reforming catalyst layer 18 of the fuel reforming unit 2 or the LTS portion. 6 LTS catalyst layer 64 absorbs heat and boils, and partly evaporates (it does not evaporate completely, and boiling is incomplete and a gas-liquid mixed phase state of 100 ° C. is obtained).

  At this time, since the gap 66 is secured between the LTS unit 6 and the water cooling tube 5, the LTS unit 6 (LTS catalyst layer 64) is radiatively cooled in the water cooling tube 5 (first raw water 31). Thus, overcooling of the LTS unit 6 (LTS catalyst layer 64) is prevented. That is, the water-cooled tube 5 has a function of blocking the heat from the high-temperature fuel reforming unit 2 to the LTS unit 6 through the heat insulating material 4 (that is, enhancing the heat insulating performance by assisting the heat insulating material 4). And the function of cooling the LTS unit 6 to remove heat generated by CO conversion in the LTS unit 6 and maintaining the LTS unit 6 at a temperature suitable for the CO conversion reaction.

  In the mixing unit 46, the reformed fuel (liquid fuel or gaseous fuel) 105 is mixed into the first raw material water 31 discharged from the water cooling tube 5. Since the 1st raw material water 31 discharged | emitted from the water cooling tube 5 has partially evaporated, the flow rate is increasing to 20 m / s-30 m / s, for example. For this reason, the reformed fuel mixed in the mixing section 46 is uniformly dispersed (mixed) in the first raw material water 31 by the stirring force at the high flow rate. In this case, the reformed fuel is a liquid fuel such as kerosene, and even if the supply volume flow rate is a small amount of, for example, 10 cc / min, the liquid fuel dropped into the first raw material water 31 having a high flow rate is uniform. To be dispersed (mixed). Therefore, no special mixer or the like is required when the reformed fuel is mixed into the raw water.

  The LTS cooling space 63 has an upper end inlet 63 a connected to the exhaust gas tube 43 and a lower end outlet 63 b connected to the exhaust gas tube 70. Accordingly, a part of the burner combustion exhaust gas discharged from the first evaporator 8 flows into the LTS cooling space 63 from the upper end inlet 63a via the exhaust gas tubes 42 and 43, and moves downward in the LTS cooling space 63. And then discharged to the exhaust gas tube 70 from the outlet 63b at the lower end. The temperature of the burner combustion exhaust gas discharged from the first evaporator 8 is reduced to, for example, about 160 ° C. by heat exchange with the mixed fluid in the first evaporator 8, and the LTS catalyst layer 64 of the LTS unit 6. And a temperature intermediate between the temperature of the water cooling tube 5 and the wall surface (cooling surface) of the outer cylinder 27 (for example, 100 ° C. to 130 ° C.). In addition, the temperature of the burner combustion exhaust gas discharged | emitted from the 1st evaporator 8 is maintaining the temperature range of 130-160 degreeC, for example in any load, the temperature of the LTS catalyst layer 64, the water cooling tube 5, and the outer cylinder 27. It is in an intermediate temperature range with the temperature of the wall (cooling surface) of

  Therefore, at the time of start-up (during preheating operation), the temperature of the LTS unit 6 (LTS catalyst layer 64) can be increased (preheated) by the heat of the burner combustion exhaust gas, and during steady operation, the heat of the burner combustion exhaust gas is cooled by water. It can be recovered by the first raw material water 31 in the tube 5. Further, the temperature change from the upstream (upper end) to the downstream (lower end) in the reformed gas flow direction in the LTS unit 6 (LTS catalyst layer 64) can be brought close to an ideal linear change (see FIG. 9). : Details will be described later).

  The winding pitch p of the water-cooled tube 5 is equal in the illustrated example (FIG. 1), but at the upper part corresponding to the upstream portion in the reformed gas flow direction of the LTS unit 6 (LTS catalyst layer 64). It is preferable to make it large and make it small in the lower part corresponding to the downstream part of the LTS part 6 (LTS catalyst layer 64) in the reformed gas flow direction. For example, the winding pitch p of the water-cooled tube 5 is about 100 mm in the upper 2/3 portion and about 50 mm in the lower 1/3 portion. The reason for this is that the reformed gas cooled to about 250 ° C. by the second evaporator 10 is upstream of the LTS unit 6 (LTS catalyst layer 64) in the reformed gas flow direction (for example, the upper 2/3). In part), in order to secure a relatively high CO conversion reaction rate, cooling (temperature reduction) is suppressed only by removing heat generated in the LTS part 6 (LTS catalyst layer 64), while LTS part 6 (LTS catalyst). In the downstream portion (for example, the lower third portion) of the reformed gas flow direction of the layer 64), the cooling is performed so that the temperature is reduced to a temperature (for example, 100 ° C. to 150 ° C.) suitable for CO selective oxidation in the PROX unit 101. It is based on the request to strengthen Since the first raw material water 31 flowing through the water-cooled tube 5 is not boiled and is in a gas-liquid mixed phase state of 100 ° C., the LTS catalyst layer 64 is not overcooled and the temperature of the LTS catalyst layer 64 is low. 100 ° C. can be maintained.

  The heat insulating material 7 is a cylindrical heat insulating material made of a ceramic fiber or the like for reducing heat radiation from the LTS portion 6 to the outside air, and is arranged concentrically with the LTS portion 6 so as to surround the LTS portion 6. Yes. Further, the heat insulating material 7 also surrounds the second evaporator 10, and is disposed concentrically with respect to the second evaporator 10. In the illustrated example (FIG. 1), there is a gap between the heat insulating material 7 and the second evaporator 10, but this gap may also be filled with a regular or irregular shaped heat insulating material.

  As shown in FIGS. 1 and 6, the PROX unit 101 is provided separately from the reformer main unit 100. A CO selective oxidation catalyst layer (hereinafter referred to as a PROX catalyst layer) formed by filling a CO selective oxidation catalyst (PROX catalyst) between an inner cylinder 81 and an outer cylinder 82 made of metal such as stainless steel constituting a double cylinder. ) Are accommodated in a first PROX catalyst layer 83 and a second PROX catalyst layer 84 that are divided into two parts in the vertical direction. Upper and lower end surfaces between the inner cylinder 81 and the outer cylinder 82 and upper and lower end surfaces of the inner cylinder 81 are closed by annular end plates 87 and 88. Further, a tube 71 is connected to the lower end of the double cylinder (outer cylinder 82), and air such as a blower (not shown) is contained in the reformed gas flowing from the LTS unit 6 to the PROX unit 101 in the middle of the tube 71. For example, 3 L / min of first PROX air 86 required for the PROX reaction sent from the supply device is mixed. A tube 90 is connected to the upper end of the double cylinder (outer cylinder 82). A cylindrical space between the first PROX catalyst layer 83 and the second PROX catalyst layer 84 serves as a mixing chamber 85, and the mixing chamber 85 converts the reformed gas flowing out from the first PROX catalyst layer 83 into the second PROX air. 89 are mixed.

  Therefore, the mixed gas of the reformed gas from the LTS unit 6 and the first PROX air 86 flows into the first PROX catalyst layer 83 via the tube 71, and CO in the reformed gas is selected in the first PROX catalyst layer 83. It is oxidized. Further, a mixed gas of the reformed gas from the first PROX catalyst layer 83 and the second PROX air 89 flows into the second PROX catalyst layer 84 through the mixing chamber 85, and further in the reformed gas in the second PROX catalyst layer 84. Of CO is selectively oxidized. As a result, the reformed gas flowing out from the second PROX catalyst layer 84 has a very low CO concentration (for example, 10 ppm or less), and this reformed gas is supplied to a fuel cell (not shown) via the tube 90.

  The PROX unit 101 is equipped with a PROX cooling unit 92 provided outside the outer cylinder 82. In the PROX cooling unit 92, the second raw material water 93 is supplied from below and flows upward. It has become. More specifically, the PROX cooling section 92 includes a cylindrical cylinder 91 made of metal such as stainless steel and is disposed concentrically with the outer cylinder 82 so as to surround the outer cylinder 82, and upper and lower end surfaces between the cylinder 91 and the outer cylinder 82 are provided. The tube is closed by end plates 102 and 103, and a tube 94 is connected to the lower end of the cylinder 91, and a tube 56 is connected to the upper end of the cylinder 91.

  Accordingly, the second raw water 93 supplied from the raw water supply device such as a pump (not shown) via the tube 94 flows into the lower end portion between the cylinder 91 and the outer cylinder 82 (PROX cooling section 92), and the cylinder. After flowing upward between 92 and the outer cylinder 82 (PROX cooling part 92), it flows out from the upper end part between the cylinder 91 and the outer cylinder 82 (PROX cooling part 92), and is subjected to the second evaporation through the tube 56. Flows into the helical tube 51 of the vessel 10. At this time, in the PROX unit 101, the second raw material water 93 removes heat generated by the PROX reaction of the reformed gas in the first PROX catalyst layer 83 and the second PROX catalyst layer 84 by boiling heat transfer, and the first PROX catalyst layer The layer 83 and the second PROX catalyst layer 84 are configured to maintain a water boiling temperature of 100 ° C., for example.

  Further, in order to preheat the first PROX catalyst layer 83 and the second PROX catalyst layer 84 at the time of startup, a cylinder 97 made of metal such as stainless steel whose upper and lower end surfaces are closed by end plates 95 and 96 is provided inside the inner cylinder 81. A cylindrical gap between the cylinder 97 and the inner cylinder 81 is an exhaust gas flow path 99. Further, a vertical pipe 98 made of metal such as stainless steel is provided so as to penetrate the center of the cylinder 97, and an upper end portion of the vertical pipe 98 extends upward through the end plate 87, and the exhaust gas tube 44. It is connected to the. Further, the end plate 87 is connected to the inlet side of the exhaust gas tube 104 including a vertical pipe portion 104a concentrically arranged with the vertical pipe 97 and a horizontal pipe portion 104b following the vertical pipe portion 104a. The outlet side of the exhaust gas tube 104 is connected to the exhaust gas tube 118, and the outlet side of the exhaust gas tube 70 is also connected to the exhaust gas tube 118. Therefore, as indicated by arrows in FIG. 2, a part of the burner combustion exhaust gas discharged from the first evaporator 8 flows into the vertical pipe 98 via the exhaust gas tubes 42 and 44 as preheating gas, and the vertical pipe 98. The gas flows downward, reverses, flows upward in the exhaust gas flow path 99, and then is discharged to the exhaust gas tube 104. Thereafter, the burner combustion exhaust gas discharged to the exhaust gas tube 104 and the burner combustion exhaust gas discharged to the exhaust gas tube 70 merge and are discharged via the exhaust gas tube 118.

  Here, the operation method at the start-up operation (preheating operation) and the steady operation (reformation operation) of the reformer will be described.

  First, preheating of each part at start-up will be described. When starting up, first, fuel 109 and air 110 are supplied to the burner 11 to ignite the burner 11. As a result, high-temperature burner combustion exhaust gas is generated, and this burner combustion exhaust gas is ejected downward from the opening 15 of the fuel combustion unit 1 and then reverses and rises in the exhaust gas flow path 20. At this time, when the burner combustion exhaust gas comes into contact with the inner cylinder 16 of the fuel reforming section 2, the fuel reforming section 2 (reforming catalyst layer 18) is preheated. At the same time, preheating of the HTS unit 3 (HTS catalyst layer 24) is also performed via the fuel reforming unit 2 by the burner combustion exhaust gas at this time. Thereafter, the burner combustion exhaust gas of, for example, a maximum of 400 ° C. flowing out from the exhaust gas flow path 20 and passing through the first evaporator 8 and the flowing exhaust gas tube 42 is branched into the exhaust gas tube 43 and the exhaust gas tube 44.

  The burner combustion exhaust gas branched into the exhaust gas tube 43 flows into the LTS cooling space 63 and flows downward in the LTS cooling space 63 (gap 66). At this time, when the burner combustion exhaust gas comes into contact with the inner cylinder 61 of the LTS unit 6, the LTS unit 6 (LTS catalyst layer 64) is preheated, and the temperature of the burner combustion exhaust gas is lowered to, for example, about 100 ° C to 150 ° C. On the other hand, the burner combustion exhaust gas branched into the exhaust gas tube 44 flows into the vertical pipe 98 of the PROX unit 101, flows downward in the vertical pipe 98, and then reverses and rises in the exhaust gas flow path 99. At this time, the second PROX catalyst layer 83 and the second PROX catalyst layer 84 are preheated to a temperature at which the raw material water does not condense (for example, a little over 100 ° C.). Finally, the burner combustion exhaust gas that has passed through the LTS cooling space 63 and the burner combustion exhaust gas that has passed through the exhaust gas flow path 99 merge through the exhaust gas tube 70 and the exhaust gas tube 104 and then exhaust through the exhaust gas tube 118. Is done.

  When preheating (heating) with the burner combustion exhaust gas is continued for a predetermined time (for example, about 40 minutes), the temperature of the reforming catalyst layer 18 of the fuel reforming unit 2 is, for example, about 700 ° C., and the HTS catalyst layer 24 of the HTS unit 3 For example, the temperature is 400 ° C., the temperature of the LTS catalyst layer 64 of the LTS unit 6 is 200 ° C. to 150 ° C., and the temperature of the first PROX catalyst layer 83 and the second PROX catalyst layer 84 of the PROX unit 101 reaches about 100 ° C., for example. , Preheating is complete. Whether or not each catalyst layer 18, 24, 64, 83, 84 has reached a predetermined preheating temperature is determined by, for example, measuring a temperature value of each catalyst layer 18, 24, 64, 83, 84 using a thermometer. It can be performed by appropriate means such as determining whether or not the preheating temperature has been reached, or determining whether or not the elapsed time after the start of the preheating operation (after burner ignition) has reached a predetermined time.

  In the preheating stage, the first raw water 31 and the second raw water 93 are not yet supplied. That is, the raw water is not yet introduced into the tubes 5, 34, 51 of the LTS cooling space 63, the first evaporator 8, and the second evaporator 10.

  Subsequently, when starting the reforming reaction, the first raw material water 31 is first supplied to the water cooling tube 5 of the LTS cooling space 63. The second raw material water 93 is supplied to the PROX cooling unit 92 of the PROX unit 101 simultaneously with the start of supply of the first raw material water 31 or after the start of supply of the first raw material water 31. Of course, when the reforming reaction is started, the supply of the reformed fuel to the mixing unit 46 is also started. The supply amounts of the raw water and the reformed fuel are set so that the S / C is, for example, 3.0 to 3.3. When the reforming reaction is started, the supply of the first PROX air 86 and the second PROX air 89 to the PROX unit 101 is also started.

  The first raw water 31 supplied to the water cooling tube 5 collects (leaks) the heat transmitted (leaks) from the fuel reforming section 2 through the heat insulating material 4 while flowing through the water cooling tube 5 and rising, and the LTS Heat exchange with burner combustion exhaust gas (for example, 150 ° C. to 400 ° C.) flowing downward through the gap 66 in the cooling space 63 causes boiling. At this time, the burner combustion exhaust gas always flows through the gap 66 in the LTS cooling space 63, so that the first raw material water flowing in the water-cooled tube 5 passes through the LTS portion 6 (LTS catalyst layer 64) preheated in the preheating operation described above. 31 does not overcool.

  Further, during steady operation, the first raw material water 31 flowing in the water cooling tube 5 radiatively cools the LTS unit 6 through the gap 66 in the LTS cooling space 63, thereby generating heat due to CO conversion of the LTS unit 6. Is absorbed (removed). Specifically, the heat generated by the CO transformation of the LTS unit 6 is radiatively cooled by the tube wall of the water-cooled tube 5 and the tube wall of the cylinder 27. There is no removal of heat generated in the LTS unit 6 by the water-cooled tube 5 (first raw water 31), and heat radiation from the heat insulating material 4 is not absorbed by the water-cooled tube 5 (first raw water 31) and is transmitted to the LTS unit 6. Then, the temperature of the LTS catalyst layer 64 of the LTS unit 6 reaches 350 ° C., for example, and the life of the LTS catalyst layer 64 is shortened.

  The first raw water 31 discharged from the water cooling tube 5 flows to the mixing unit 46. In the mixing unit 46, the reformed fuel 105 (liquid fuel or gaseous fuel) supplied from a reformed fuel supply device such as a pump or a blower (not shown) is mixed into the first raw material water 31. At this time, since the first raw water 31 is boiling water at about 100 ° C. and has a high flow rate of, for example, about 20 m / s, the reformed fuel has its stirring power in the flow of the first raw water 31. With stirring.

  The mixed fluid of the first raw water 31 and the reformed fuel 105 discharged from the mixing unit 46 flows in the spiral tube 34 of the first evaporator 8. At this time, burner combustion exhaust gas at a maximum of 500 ° C. has already flowed into the first evaporator 8 and flows through the gaps 8a and 8b, and heat exchange occurs between the burner combustion exhaust gas and the mixed fluid. The first raw material water 31 in the mixed fluid that has passed through the vessel 8 becomes, for example, superheated steam at about 400 ° C. in which a reforming catalytic reaction occurs. When the reformed fuel 105 is a liquid fuel, the liquid fuel is also evaporated by the heat of the burner combustion exhaust gas in the first evaporator 8.

  The mixed steam of the first raw material water 31 and the reformed fuel 105 discharged from the first evaporator 8 flows into the fuel reforming unit 2 through the mixer tube 47 and the header 58, and the fuel reforming unit 2 It flows in the reforming catalyst layer 18 downward. At this time, in the fuel reforming unit 2, the reformed fuel 105 in the mixed steam contacting with the reforming catalyst is indirectly countercurrently contacted with the burner combustion exhaust gas rising in the exhaust gas passage 20 together with the water vapor in the mixed steam. The burner combustion exhaust gas receives heat and is reformed into a reformed gas containing hydrogen gas.

  The reformed gas generated in the fuel reforming unit 2 flows into the HTS unit 3 via the reformed gas reversal raising unit 22 and flows upward in the HTS catalyst layer 24. The reformed gas discharged from the HTS unit 3 flows into the LTS unit 6 through the second evaporator 10 (spiral tube 51), and flows downward in the LTS catalyst layer 64 of the LTS unit 6. At this time, in the LTS unit 3 and the HTS unit 6, the reformed gas undergoes CO conversion at the respective temperature levels as described above, and the hydrogen content in the reformed gas increases. Subsequently, the reformed gas discharged from the LTS unit 6 sequentially moves upward in the first PROX catalyst layer 83 and the second PROX catalyst layer 84 of the PROX unit 101 together with the first PROX air 86 and the second PROX air 89. The CO in the reformed gas in the reformed gas is selectively oxidized by the first PROX air 86 and the second PROX air 89 during this period, so that the CO concentration can be used in the fuel cell (for example, 10 ppm). The following.

  On the other hand, when the selective oxidation reaction of CO proceeds in the first PROX catalyst layer 83 and the second PROX catalyst layer 84, heat is generated, and the temperature of the first PROX catalyst layer 83 and the second PROX catalyst layer 84 becomes too high and the PROX catalyst is appropriate. Will no longer work. In order for the PROX catalyst to work properly, it is necessary to maintain its temperature at, for example, 100 ° C. For this reason, the second raw material water 93 is supplied to the PROX cooling unit 92 of the PROX unit 101. The second raw material water 93 flows into the PROX cooling section 92 from below and flows upward in the PROX cooling section 93. During this time, the second raw material water 93 is partially heated by the heat generated by the first PROX catalyst layer 83 and the second PROX catalyst layer 84 to be in a gas-liquid mixed phase state. The second raw material water 93 in the gas-liquid mixed phase state has a remarkably high heat transfer coefficient and does not enter a superheated state due to completion of boiling, so that the temperature is constant at about 100 ° C. Therefore, by cooling the second raw material water 93, the first PROX catalyst layer 83 and the second PROX catalyst layer 84 are very easily maintained at the optimum temperature (for example, 100 ° C.) and exhibit their characteristics in the optimum state. Is possible.

  The second raw material water 93 flowing out from the PROX cooling unit 92 flows into the spiral tube 51 of the second evaporator 10 and flows downward in the spiral tube 51. During this time, the second raw material water 93 and the reformed gas flowing upward through the gap 10a of the second evaporator 10 undergo heat exchange, whereby the second raw material water 93 is completely evaporated and overheated at, for example, about 400 ° C. The reformed gas is reduced to a temperature of, for example, about 250 ° C. to 200 ° C. suitable for the LTS unit 6 from a temperature of about 450 ° C. when the reformed gas flows into the second evaporator 10 from the HTS unit 3. That is, the amount of water of the second raw material water 93 is such that the amount of heat exchange between the second raw material water 93 and the reformed gas in the second evaporator 10 is reduced from about 250 ° C. to 200 ° C. It sets so that it may become the heat exchange amount which can be warmed. Then, a water amount obtained by subtracting the second raw material water 93 from the total raw material water amount necessary for reforming the reformed fuel in the fuel reforming unit 2 is set as the water amount of the first raw material water 31. The second raw material water 83 flowing out from the spiral tube 51 of the second evaporator 10 is mixed with the mixed steam from the first evaporator 8 in the mixer tube 48 and supplied to the fuel reforming unit 2 via the header 58. Thus, it is used for the reforming reaction in the fuel reforming section 2.

  Next, the temperature control of the fuel reforming unit 2 and the temperature control of the first evaporator 8 during steady operation will be described based on FIGS.

  As shown in FIG. 1, a first thermometer 106 is installed at the lower end of the reforming catalyst layer 18 of the fuel reforming unit 2 and connected to the outlet 34 b of the spiral tube 34 of the first evaporator 8. A second thermometer 107 is installed in the tube 47. The first thermometer 106 detects the maximum temperature of the fuel reforming unit 2. That is, since the lower end portion of the reforming catalyst layer 18 is heated by the burner combustion exhaust gas having the highest temperature (for example, about 1000 ° C.) immediately after being ejected from the opening 15 of the fuel combustion portion 1, the entire reforming catalyst layer 18 is heated. Among these, the temperature is the highest, and the temperature at the lower end is measured by the first thermometer 106. On the other hand, the second thermometer 107 detects the temperature of the mixed steam discharged from the spiral tube 34 of the first evaporator 8 and supplied to the fuel reforming unit 2.

  As shown in FIG. 8, the temperature measurement signal of the first thermometer 106 and the temperature measurement signal of the second thermometer 107 are both input to the temperature control device 108. The temperature control device 108 controls the fuel supply device 111 such as a pump and a blower based on the temperature measurement value of the lower end temperature (maximum temperature) of the reforming catalyst layer 18 by the first thermometer 106, thereby The amount of fuel 109 (liquid fuel or gaseous fuel) supplied from the supply device 111 to the burner 11 is controlled to maintain the temperature measurement value within a predetermined temperature range (for example, a range of 700 ° C. ± 10 ° C.). . In this case, the control of the fuel supply device 111 includes, for example, the opening control of the fuel flow control valve and the output (discharge amount) control of the fuel supply pump or blower. Further, in the temperature control device 108, an air supply device 112 such as a blower is provided on the basis of the temperature measurement value of the mixed steam discharged from the spiral tube 34 and supplied to the fuel reforming unit 2 by the first thermometer 107. By controlling, the supply amount (dilution air amount) of the air 110 supplied from the air supply device 112 to the burner 11 is controlled, and the temperature measurement value is set within a predetermined temperature range (for example, a range of 400 ° C. ± 50 ° C.). Keep in. In this case, control of the air supply device 112 includes, for example, opening control of an air flow rate adjustment valve and output (discharge amount) control of an air supply blower.

  When the supply amount of the fuel 109 is increased, the burner combustion exhaust gas temperature increases, so that the lower end temperature of the reforming catalyst layer 18 increases. Conversely, when the supply amount of the combustion 109 is decreased, the burner burner combustion exhaust gas temperature decreases. The temperature at the lower end of the quality catalyst layer 18 decreases. Therefore, in the temperature control device 108, when the temperature measurement value at the lower end portion of the reforming catalyst layer 18 is equal to or higher than a predetermined temperature range (for example, 700 ° C. + 10 ° C. or higher), the supply amount of the fuel 109 is reduced to a predetermined temperature. The fuel supply device 111 is controlled so as to increase the fuel 109 when the temperature is below the range (for example, 700 ° C.-10 ° C. or less).

  Further, when the supply amount of the air 110 is increased, the burner combustion exhaust gas temperature is decreased by being diluted with the air, so that the heat exchange amount between the burner combustion exhaust gas and the reforming catalyst layer 18 is reduced, and the upper first evaporation is performed. Since the amount of heat of the burner combustion exhaust gas carried to the vessel 8 increases, the temperature of the mixed steam discharged from the spiral tube 34 rises. Conversely, if the supply amount of the air 110 is decreased, the dilution effect by the air is reduced. As the burner combustion exhaust gas temperature rises, the amount of heat exchange between the burner combustion exhaust gas and the reforming catalyst layer 18 increases, and the amount of heat of the burner combustion exhaust gas conveyed to the upper first evaporator 8 decreases. The temperature of the mixed steam discharged from the tube 34 decreases. Therefore, in the temperature control device 108, when the temperature measurement value of the mixed steam discharged from the spiral tube 34 becomes a predetermined temperature range or more (for example, 400 ° C. + 50 ° C. or more), the supply amount of the air 110 is reduced, The fuel supply device 111 is controlled so as to increase the air 110 when the temperature is below the temperature range (for example, 400 ° C.-50 ° C. or less).

  Note that the temperature range of the lower end portion of the reforming catalyst layer 18 (for example, a range of 700 ° C. ± 10 ° C.) and the temperature range of the mixed steam discharged from the spiral tube 34 (for example, a range of 400 ° C. ± 50 ° C.) are different. This is to improve the stability of temperature control. That is, if both of the temperature ranges are narrowed, it is repeated that the other temperature deviates from the predetermined temperature range when trying to bring one temperature into the predetermined temperature range, Temperature control may become unstable. For this reason, the former temperature range with relatively severe temperature conditions is narrowed, and the latter temperature range with relatively mild temperature conditions is widened to enhance the stability of temperature control.

  From the above, according to the first embodiment, the following effects can be obtained.

  That is, according to the first embodiment, the first raw water 31 having the water cooling tube 5 wound around the outer peripheral surface of the cylinder 27 surrounding the heat insulating material 4 and flowing through the water cooling tube 5 is provided. Since the heat of the fuel reforming part 2 transmitted from the inside of the heat insulating material 4 to the water cooling tube 5 through the heat insulating material 4 is absorbed and boiled, the heat of the fuel reforming part 2 leaking from the heat insulating material 4 is absorbed. Since the water cooling tube 5 can recover the heat of evaporation of the first raw material water 31, the heat insulating material 4 is inexpensive and has a low heat insulating performance. This will not cause a decrease in efficiency. For this reason, it is possible to reduce the manufacturing cost and size of the reformer.

  Further, according to the first embodiment, the reformed fuel 105 is mixed into the first raw water 31 boiled in the water-cooled tube 5, so that, for example, when kerosene is used as the reformed fuel 105, Pre-evaporation is unnecessary, temperature control of the burner combustion exhaust gas for boiling kerosene is unnecessary, and the reformed fuel is contained in the steam of the first raw material water 31 that has boiled and increased in flow rate (for example, 20 to 30 m / s). Therefore, the reformed fuel 105 can be easily mixed uniformly with the first raw material water 31 (steam) without using a special mixer in the mixing unit 46. Further, in the first evaporator 8, the reformed fuel 105 evaporates together with the raw water (steam) (for example, the temperature rises to about 400 ° C.), so that the reformed fuel 105 to the fuel reforming section 2 is not generated without causing oscillation. Supply can be performed uniformly and there is no carbon deposition.

  Further, according to the first embodiment, the first evaporator 8 causes the mixed fluid of the first raw water 31 and the reformed fuel 105 to flow through the spiral tube 34 provided in the double cylinder. Since it is configured to evaporate by heating with the burner combustion exhaust gas flowing through the gaps 8a and 8b between the inner wall surface of the double cylinder and the spiral tube 34, the heat of the burner combustion exhaust gas is used effectively and efficiently. The mixed fluid can be evaporated.

  Further, according to the first embodiment, in the first evaporator 8, the balls 35 as heat transfer promoting materials are filled in the gaps 8 a and 8 b between the inner wall surface of the double cylinder and the spiral tube 34. Therefore, the heat of the burner combustion exhaust gas is not only directly transmitted from the burner combustion exhaust gas to the tube wall of the spiral tube 34 but also transmitted to the tube wall of the spiral tube 34 through the ball 35, so that the mixed fluid The heat transfer of the burner combustion exhaust gas is promoted. Further, the ball 35 functions as a resistance for making the flow distribution of the burner combustion exhaust gas uniform, and as a heat storage material that maintains the temperature of the mixed fluid even when the thermal balance between the mixed fluid and the burner combustion exhaust gas is lost. It can also serve a function.

  Further, according to the first embodiment, the first raw material water 31 flowing through the water cooling tube 5 is allowed to pass through the gap 66 by holding the gap 66 between the LTS unit 6 and the water cooling tube 5. Since the LTS catalyst layer 64 of the LTS unit 6 is radiatively cooled, the LTS catalyst layer 64 is prevented from being overcooled, and the LTS catalyst layer 64 is maintained at a temperature suitable for the CO shift reaction (for example, around 200 ° C.). be able to.

  Further, according to the first embodiment, the LTS unit 6 can be heated by flowing the burner combustion exhaust gas through the gap 66 between the LTS unit 6 and the water-cooled tube 5. In the preheating operation), the LTS catalyst layer 64 of the LTS unit 6 can be preheated by effectively using the heat of the burner combustion exhaust gas.

  Further, according to the first embodiment, the burner combustion exhaust gas flowing through the gap 66 between the LTS unit 6 and the water cooling tube 5 heats the reforming catalyst layer 18 in the fuel reforming unit 2, and further the first A configuration in which the mixed fluid is heated by the evaporator 8 to be reduced to an intermediate temperature between the temperature of the LTS catalyst layer 64 of the LTS unit 6 and the wall surface temperature of the water-cooled tube 5 and the cylinder 27 and supplied to the gap 66. Therefore, the burner combustion exhaust gas alleviates a decrease in temperature particularly on the upstream side (upper part) of the LTS catalyst layer 64 in the reformed gas flow direction, and upstream of the LTS catalyst layer 64 in the reformed gas flow direction (high temperature). Part) to the downstream (low temperature part) can be brought close to an ideal linear change. Referring to FIG. 9, the temperature distribution (temperature gradient) of the LTS catalyst layer 64 shown in FIG. 9A is indicated by a one-dot chain line in FIG. 9B when the burner combustion exhaust gas does not flow through the gap 66. As shown in FIG. 9C, when the burner combustion exhaust gas is caused to flow through the gap 66, the temperature drop is relatively large in the upper portion (high temperature portion) of the LTS catalyst layer 64. Even in the upper part (high temperature part) of the LTS catalyst layer 64, the temperature drop is relatively small, and the distribution approaches the ideal linear change shown by the solid line in FIG.

  Further, according to the first embodiment, the HTS unit 3 is arranged so as to surround the fuel reforming unit 2 so that the burner combustion exhaust gas can be heated via the fuel reforming unit 2. Therefore, at the time of start-up (during preheating operation), the reforming catalyst layer 18 of the fuel reforming unit 2 can be preheated with the burner combustion exhaust gas, and at the same time, the HTS catalyst layer 24 of the HTS unit 3 can be preheated. That is, the HTS catalyst layer 24 of the HTS part 3 can be easily preheated with a simple configuration.

  Further, according to the first embodiment, the second raw material water 93 is circulated through the spiral tube 51 provided in the double cylinder, and between the inner wall surface of the double cylinder and the spiral tube 51. Since it has the 2nd evaporator 10 of the composition evaporated by heating with the reformed gas from the HTS part 3 which flows through gap 10a, the 2nd raw material water 93 is efficiently used effectively using the heat of the reformed gas. Can be evaporated. That is, the heating (evaporation) of the second raw material water 93 and the temperature reduction of the reformed gas can be performed efficiently.

  Further, according to the first embodiment, the PROX unit 101 is provided with the PROX cooling unit 92 extending in the vertical direction along the side surfaces of the first and second PROX catalyst layers 83 and 84 arranged in the vertical direction. The second raw material water 93 is supplied from the lower end of the PROX cooling unit 92 and is circulated upward in the PROX cooling unit 92 to cool the first and second PROX catalyst layers 83 and 84. Compared to the case where the second raw material water 93 is supplied from the upper end of the PROX cooling unit 92 and circulated downward, the entire raw material water in the PROX cooling unit 92 can be easily brought to the boiling temperature (for example, 100 ° C.). . That is, when the second raw material water 93 is supplied from the upper end of the PROX cooling unit 92, the boiled second raw material water 93 does not flow downward, but only the cold second raw material water 93 flows downward first. Therefore, it is difficult to bring the entire raw water in the PROX cooling section 92 to a uniform boiling temperature. However, when the second raw water 93 is supplied from the lower end of the PROX cooling section 92, the boiled second raw water Since 93 immediately flows upward, the entire raw material water in the PROX cooling section 92 can be easily brought to a uniform boiling temperature. For this reason, the temperature of the first and second PROX catalyst layers 83 and 84 can be easily set to a temperature suitable for the CO selective oxidation reaction.

  Further, according to the first embodiment, the PROX unit 101 converts the burner combustion exhaust gas after heating the reforming catalyst layer 18 of the fuel reforming unit 2 into the side surfaces of the first and second PROX catalyst layers 83 and 84. Since the first and second PROX catalyst layers 83 and 84 can be heated by flowing through the exhaust gas flow path 99 provided along the exhaust gas flow path 99, the heat of the burner combustion exhaust gas is effective at the time of start-up (during preheating operation). The first and second PROX catalyst layers 83 and 84 of the PROX unit 101 can be preheated.

  In addition, as a method for operating the reformer, the catalyst layers 18, 24, 64, and 64 of the fuel reforming unit 2, the HTS unit 3, the LTS unit 6, and the PROX unit 101 are used by the burner combustion exhaust gas during the preheating operation at the time of startup. 83 and 84 are efficiently heated, and after the preheating operation (after each catalyst layer reaches a predetermined preheating temperature), the supply of the first raw material water 31 to the water cooling tube 5 and the reformed fuel 105 to the mixing unit 46 are performed. And supply of the second raw material water 93 to the PROX cooling section 92 can be started to start generation of the reformed gas.

  Further, as an operation method of the reformer, during the steady operation, the maximum temperature of the reforming catalyst layer 18 of the fuel reforming unit 2 is measured, and this temperature measurement value is maintained within a predetermined temperature range. The amount of fuel supplied to the burner 11 is controlled, the vapor temperature of the mixed fluid discharged from the first evaporator 8 and supplied to the fuel reforming unit 2 is measured, and this temperature measurement value is set within a predetermined temperature range. In order to control the amount of air supplied to the burner 11 so as to be maintained within, the maximum temperature of the reforming catalyst layer 18 and the vapor temperature of the mixed fluid are reliably maintained within the respective predetermined temperature ranges. Can do.

<Embodiment 2>
FIG. 10 is a cross-sectional view showing the configuration of the main body of the reformer according to Embodiment 2 of the present invention, and FIG. 2 is a cross-sectional view showing the configuration of the CO selective oxidation unit of the reformer. 10 and 11, the same reference numerals are given to the same parts as those in the first embodiment (see FIGS. 1 and 2), and the detailed description thereof is omitted.

  As shown in FIGS. 10 and 11, in the reforming apparatus of the second embodiment, the upper end (exit) of the PROX cooling unit 92 of the PROX unit 101 and the inlet 5 a of the water cooling tube 5 of the LTS cooling space 63 are used. Are connected via a tube 56. Accordingly, the second raw material water 93 flows through the PROX cooling unit 92, then flows into the water-cooled tube 5 from the inlet 5 a through the tube 56, and flows through the water-cooled tube 5 and rises. At this time, the second raw material water 93 is partly boiled by the heat generated by the first PROX catalyst layer 83 and the second PROX catalyst layer 84 in the PROX cooling unit 92, and is further insulated from the fuel reforming unit 2 in the water cooling tube 5. Part is boiled by receiving heat (leaking) through the material 4 and heat generated by the LTS unit 6.

  Further, the outlet 5 b of the water cooling tube 5 is connected to the inlet 51 a of the spiral tube 51 of the second evaporator 10 through the tube 121. Accordingly, the second raw material water 93 discharged from the water cooling tube 5 flows into the spiral tube 51 from the inlet 51a via the tube 121 and flows downward in the spiral tube 51. For this reason, in the second evaporator 10, heat exchange between the second raw material water 93 from the water-cooled tube 5 and the reformed gas from the HTS unit 3 is performed. As a result, the second raw material water 93 is completely evaporated and becomes superheated steam of about 400 ° C., for example, and discharged to the mixer tube 48, and the reformed gas is reduced in temperature from about 400 ° C. to about 250 ° C. to 200 ° C., for example. And discharged to the LTS unit 6. That is, the amount of the second raw material water 93 is set so as to satisfy such a temperature condition, and this second raw material water 93 is used as the total raw material necessary for reforming the reformed fuel in the fuel reforming unit 2. The amount of water subtracted from the amount of water is set as the amount of water of the first raw material water 31.

  However, in the second embodiment, unlike the first embodiment, the first raw water 31 is supplied to the mixer 122 from a raw water supply device such as a pump (not shown). The mixer 122 is connected to the inlet 34 a of the spiral tube 34 of the first evaporator 8 through the tube 123. In the mixer 122, the reformed fuel 105 (liquid fuel or gaseous fuel) is mixed into the first raw material water 31. Therefore, the mixed fluid of the first raw material water 31 and the reformed fuel 105 discharged from the mixer 122 flows into the spiral tube 34 from the inlet 34a through the tube 123 and flows downward in the spiral tube 34. . For this reason, in the first evaporator 8, heat exchange between the mixed fluid from the mixer 122 and the burner combustion exhaust gas from the exhaust gas passage 20 is performed. As a result, the mixed fluid becomes superheated steam of about 400 ° C., for example, and is discharged to the mixer tube 48. Further, unlike the case of the first embodiment, the exhaust gas tube 42 is also provided with a portion on the inlet side between the vertical pipe 13 and the first evaporator 8 (inner cylinder 32) and extends downward. The exhaust gas flow path 20 is communicated.

  In the second embodiment, the upper end portion of the first evaporator 8 (outer cylinder 33) is connected to one inflow portion 125a of the valve 125 as the discharge switching means via the exhaust gas tube 124. An exhaust gas tube 118 is connected to the other inflow portion 125 b of the valve 125, and an exhaust gas tube 126 is connected to the outflow portion 125 c of the valve 125. The valve 125 has a function of switching the flow direction at a predetermined temperature, such as a thermo valve. For example, when the burner combustion exhaust gas from the exhaust gas tube 118 flows into the inflow portion 125b and flows out of the inflow portion 125c, when the temperature of the burner combustion exhaust gas reaches a predetermined temperature (for example, 120 ° C.), the flow of the valve 125 The path is switched from the inflow portion 125b side to the inflow portion 125a side, and the burner combustion exhaust gas from the exhaust gas tube 124 flows from the inflow portion 125a and flows out from the outflow portion 125c.

  When the temperature of the burner combustion exhaust gas flowing into the inflow portion 125b of the valve 125 from the exhaust gas tube 118 reaches a predetermined temperature (for example, 120 ° C.), the temperatures of the LTS catalyst layer 64, the first PROX catalyst layer 83, and the second PROX catalyst layer 84 are also increased. A predetermined preheating temperature is reached. In other words, the valve 125 flows from the inlet 125b side to the 125a side at the temperature of the burner combustion exhaust gas when the temperatures of the LTS catalyst layer 64, the first PROX catalyst layer 83, and the second PROX catalyst layer 84 reach a predetermined preheating temperature. The road is set to switch.

  Here, the operation method at the start-up operation and the steady operation of the reformer will be described.

  First, preheating of each part at start-up will be described. When starting up, first, fuel 109 and air 110 are supplied to the burner 11 to ignite the burner 11. As a result, high-temperature burner combustion exhaust gas is generated, and this burner combustion exhaust gas is ejected downward from the opening 15 of the fuel combustion unit 1 and then reverses and rises in the exhaust gas flow path 20. At this time, when the burner combustion exhaust gas comes into contact with the inner cylinder 16 of the fuel reforming section 2, the fuel reforming section 2 (reforming catalyst layer 18) is preheated. At the same time, preheating of the HTS unit 3 (HTS catalyst layer 24) is also performed via the fuel reforming unit 2 by the burner combustion exhaust gas at this time. At this time, the valve 125 is in a state where the flow path on the inflow portion 125a side is closed and the flow path on the inflow portion 125b side is opened, so that the burner combustion exhaust gas discharged from the exhaust gas flow path 20 is The first evaporator 8 is bypassed and flows into the exhaust gas tube 42. The burner combustion exhaust gas that has passed through the exhaust gas tube 42 is branched into an exhaust gas tube 43 and an exhaust gas tube 44.

  The burner combustion exhaust gas branched into the exhaust gas tube 43 flows into the LTS cooling space 63 and flows downward in the LTS cooling space 63 (gap 66). At this time, when the burner combustion exhaust gas comes into contact with the inner cylinder 61 of the LTS unit 6, the LTS unit 6 (LTS catalyst layer 64) is preheated, and the temperature of the burner combustion exhaust gas is lowered to, for example, about 100 ° C to 150 ° C. On the other hand, the burner combustion exhaust gas branched into the exhaust gas tube 44 flows into the vertical pipe 98 of the PROX unit 101, flows downward in the vertical pipe 98, and then reverses and rises in the exhaust gas flow path 99. At this time, the second PROX catalyst layer 83 and the second PROX catalyst layer 84 are preheated by the burner combustion exhaust gas to a temperature at which the raw water is not condensed (for example, a little over 100 ° C.). Finally, the burner combustion exhaust gas that has passed through the LTS cooling space 63 and the burner combustion exhaust gas that has passed through the exhaust gas flow path 99 merge through the exhaust gas tube 70 and the exhaust gas tube 104, and then flow out from the inflow portion 125 b of the valve 125. The gas flows to the portion 125c (passes through the valve 125) and is exhausted through the exhaust gas tube 118.

  When preheating (heating) with the burner combustion exhaust gas is continued for a predetermined time (for example, about 40 minutes), the temperature of the reforming catalyst layer 18 of the fuel reforming unit 2 is, for example, about 700 ° C., and the HTS catalyst layer 24 of the HTS unit 3 For example, the temperature is 400 ° C., the temperature of the LTS catalyst layer 64 of the LTS unit 6 is 200 ° C. to 150 ° C., and the temperature of the first PROX catalyst layer 83 and the second PROX catalyst layer 84 of the PROX unit 101 reaches about 100 ° C., for example. , Preheating is complete.

  At this time, since the temperature of the burner combustion exhaust gas flowing into the valve 125 from the inflow portion 125b reaches a predetermined temperature (for example, 120 ° C.), the flow path of the valve 125 is switched from the inflow portion 125b side to the inflow portion 125a side. As a result, the burner combustion exhaust gas flowing into the inflow portion 125a from the first evaporator 8 through the exhaust gas tube 124 passes through the valve 125 and is exhausted through the exhaust gas tube 118. That is, the burner combustion exhaust gas from the exhaust gas passage 20 flows to the first evaporator 8. On the other hand, the burner combustion exhaust gas does not flow into the exhaust gas tube 142. That is, burner combustion exhaust gas does not flow to the PROX unit 101 or the like during steady operation after completion of preheating. In the preheating stage, the first raw water 31 and the second raw water 89 are not yet supplied. That is, the raw water is not yet introduced into the tubes 5, 34, 51 of the LTS cooling space 63, the first evaporator 8, and the second evaporator 10.

  Subsequently, in order to start the reforming reaction, the first raw water 31 and the reformed fuel 105 are supplied and mixed by the mixer 122, and this mixed fluid is supplied to the spiral tube 34 of the first evaporator 8. The second raw material water 93 is also supplied to the PROX cooling unit 92 of the PROX unit 101 simultaneously with the start of supply of the first raw material water 31 or after the start of supply of the first raw material water 31. When the reforming reaction is started, the supply of the first PROX air 86 and the second PROX air 89 to the PROX unit 101 is also started.

  The mixed fluid flowing in the spiral tube 34 of the first evaporator 8 exchanges heat with the burner combustion exhaust gas flowing in the gaps 8 a and 8 b in the first evaporator 8. As a result, the first raw water 31 becomes superheated steam at about 400 ° C., for example. When the reformed fuel 105 is a liquid fuel, the liquid fuel is also evaporated by the burner combustion exhaust gas in the first evaporator 8. The mixed steam of the first raw material water 31 and the reformed fuel 105 discharged from the first evaporator 8 flows into the fuel reforming unit 2 through the mixer tube 47 and the header 58, and the fuel reforming unit 2 It flows in the reforming catalyst layer 18 downward. At this time, in the fuel reforming unit 2, the reformed fuel 105 in the mixed steam contacting with the reforming catalyst is indirectly countercurrently contacted with the burner combustion exhaust gas rising in the exhaust gas passage 20 together with the water vapor in the mixed steam. The burner combustion exhaust gas receives heat and is reformed into a reformed gas containing hydrogen gas.

  The reformed gas generated in the fuel reforming unit 2 flows into the HTS unit 3 via the reformed gas reversal raising unit 22 and flows upward in the HTS catalyst layer 24. The reformed gas that has flowed out of the HTS unit 3 flows into the LTS unit 6 via the second evaporator 10 (spiral tube 51), and flows downward in the LTS catalyst layer 64 of the LTS unit 6. At this time, in the LTS unit 3 and the HTS unit 6, the reformed gas undergoes CO conversion at the respective temperature levels as described above, and the hydrogen content in the reformed gas increases. Subsequently, the reformed gas that has flowed out of the LTS unit 6 sequentially flows upward in the first PROX catalyst layer 83 and the second PROX catalyst layer 84 of the PROX unit 101 together with the first PROX air 86 and the second PROX air 89. During this time, CO in the reformed gas in the reformed gas is selectively oxidized by the first PROX air 86 and the second PROX air 89, so that the CO concentration can be used in the fuel cell (for example, 10 ppm or less). )

  On the other hand, the second raw material water 93 flows into the PROX cooling unit 92 from below and flows upward in the PROX cooling unit 93. During this time, the second raw material water 93 is partially heated by the heat generated by the first PROX catalyst layer 83 and the second PROX catalyst layer 84 to be in a gas-liquid mixed phase state. The second raw material water 93 in the gas-liquid mixed phase state has a remarkably high heat transfer coefficient, and the temperature thereof is constant at about 100 ° C., for example, because it does not become overheated upon completion of boiling. Therefore, by cooling the second raw material water 93, the first PROX catalyst layer 83 and the second PROX catalyst layer 84 are very easily maintained at the optimum temperature (for example, 100 ° C.) and exhibit their characteristics in the optimum state. Is possible.

  The second raw material water 93 discharged from the PROX cooling unit 92 flows into the water cooling tube 5 of the LTS cooling space 63 and flows upward in the water cooling tube 5. During this time, the second raw material water 93 is boiled by collecting the heat transmitted (leaked) from the fuel reforming section 2 through the heat insulating material 4. Further, during the steady operation, the second raw water 93 flowing in the water cooling tube 5 absorbs the heat generated by the CO transformation of the LTS unit 6 by radiative cooling through the gap 66 in the LTS cooling space 63 ( Remove. Specifically, the heat generated by the CO transformation of the LTS unit 6 is radiatively cooled by the tube wall of the water-cooled tube 5 and the tube wall of the cylinder 27.

  The second raw water 93 discharged from the water cooling tube 5 flows into the spiral tube 51 of the second evaporator 10 and flows downward in the spiral tube 51. During this time, the second raw material water 93 and the reformed gas flowing upward through the gap 10a of the second evaporator 10 are heat-exchanged, whereby the second raw material water 93 is completely evaporated and, for example, about 400 ° C. superheated steam. Thus, the reformed gas is reduced in temperature from, for example, about 450 ° C. when flowing into the second evaporator 10 from the HTS unit 3 to a temperature of, for example, about 250 ° C. to 200 ° C. suitable for the LTS unit 6. That is, the amount of water of the second raw material water 93 is such that the amount of heat exchange between the second raw material water 93 and the reformed gas in the second evaporator 10 is reduced from about 250 ° C. to 200 ° C. It sets so that it may become the heat exchange amount which can be warmed. Then, a water amount obtained by subtracting the second raw material water 93 from the total raw material water amount necessary for reforming the reformed fuel in the fuel reforming unit 2 is set as the water amount of the first raw material water 31. The second raw material water 83 discharged from the spiral tube 51 of the second evaporator 10 is mixed with the mixed steam from the first evaporator 8 in the mixer tube 48 and supplied to the fuel reforming unit 2 via the header 58. By doing so, it is used for the reforming reaction in the fuel reforming section 2.

  Although not described in detail, in this reformer as well, in the same manner as in the first embodiment, the temperature control device 108 uses the temperature measurement signals from the first thermometer 106 and the second thermometer 107 based on the temperature measurement signals. The temperature control of the lower end portion of the reforming catalyst layer 18 and the temperature control of the mixed steam discharged from the spiral tube 34 of the first evaporator 8 are performed.

  According to the second embodiment, the same effect as in the second embodiment can be obtained.

  That is, according to the second embodiment, the first raw material water 31 having the water cooling tube 5 wound around the outer peripheral surface of the cylinder 27 surrounding the heat insulating material 4 and circulating in the water cooling tube 5 is Since the heat of the fuel reforming part 2 transmitted from the inside of the heat insulating material 4 to the water cooling tube 5 through the heat insulating material 4 is absorbed and boiled, the heat of the fuel reforming part 2 leaking from the heat insulating material 4 is absorbed. Since the water cooling tube 5 can recover the heat of evaporation of the first raw material water 31, the heat insulating material 4 is inexpensive and has a low heat insulating performance. This will not cause a decrease in efficiency. For this reason, it is possible to reduce the manufacturing cost and size of the reformer.

  Further, according to the second embodiment, the mixed fluid of the reformed fuel 105 and the first raw water 31 is circulated in the spiral tube 34 provided in the double cylinder, and the inner wall surface of the double cylinder And the first evaporator 8 configured to evaporate by heating with the burner combustion exhaust gas flowing through the gaps 8a and 8b between the spiral tube 34 and efficiently using the heat of the burner combustion exhaust gas. The mixed fluid can be evaporated.

  Further, according to the second embodiment, since the burner combustion exhaust gas after heating the reforming catalyst layer 18 of the fuel reforming section 2 is configured to flow through the gaps 8a and 8b of the first evaporator 8, the reforming is performed. The mixed fluid can be evaporated by effectively using the heat of the burner combustion exhaust gas after heating the catalyst layer 2.

  Further, according to the second embodiment, since the gaps 8a and 8b between the inner wall surface of the double cylinder and the spiral tube 34 are filled with the ball 35 as the heat transfer promoting material, the heat of the burner combustion exhaust gas. Is not only transmitted from the burner combustion exhaust gas directly to the tube wall of the spiral tube 34 but also transmitted to the tube wall of the spiral tube 34 via the ball 35, and therefore, the heat of the burner combustion exhaust gas to the mixed fluid. Is promoted. Further, the ball 35 functions as a resistance for making the flow distribution of the burner combustion exhaust gas uniform, and a heat storage material that maintains the temperature of the mixed fluid even when the thermal balance between the mixed fluid and the burner combustion exhaust gas is lost. It can also serve as

  Further, according to the second embodiment, the first raw material water 93 flowing through the water cooling tube 5 is passed through the gap 66 by holding the gap 66 between the LTS unit 6 and the water cooling tube 5. Since the LTS catalyst layer 64 of the LTS unit 6 is radiatively cooled, the LTS catalyst layer 64 is prevented from being overcooled and the LTS catalyst layer 64 is maintained at a temperature suitable for the CO shift reaction (for example, around 200 ° C.). can do.

  Further, according to the second embodiment, the burner combustion exhaust gas after heating the reforming catalyst layer 18 of the fuel reforming section 2 is caused to flow in the gap 66 between the LTS section 6 and the water cooling tube 5, Since the LTS unit 6 can be heated, the LTS catalyst layer 64 of the LTS unit 6 can be preheated by effectively using the heat of the burner combustion exhaust gas at the time of start-up (during preheating operation).

  Further, according to the second embodiment, the HTS unit 3 is arranged so as to surround the fuel reforming unit 2 so that the burner combustion exhaust gas can be heated via the fuel reforming unit 2. Therefore, at the time of start-up (during preheating operation), the reforming catalyst layer 18 of the fuel reforming unit 2 can be preheated with the burner combustion exhaust gas, and at the same time, the HTS catalyst layer 24 of the HTS unit 3 can be preheated. That is, the HTS catalyst layer 24 of the HTS part 3 can be easily preheated with a simple configuration.

  Further, according to the second embodiment, the second raw material water 93 discharged from the water-cooled tube 5 is circulated through the spiral tube 51 provided in the double cylinder, and the inner wall surface of the double cylinder and the spiral Since it has the 2nd evaporator 10 of the composition evaporated by heating with the reformed gas from the HTS part 3 which flows through the gap between tube-like tubes 51, the heat of the reformed gas is used effectively and efficiently The second raw material water 93 can be evaporated. That is, the heating (evaporation) of the second raw material water 93 and the temperature reduction of the reformed gas can be performed efficiently.

  Further, according to the second embodiment, the PROX unit 101 is provided with the PROX cooling unit 92 extending in the vertical direction along the side surfaces of the first and second PROX catalyst layers 83 and 84 arranged in the vertical direction. The second raw material water 93 is supplied from the lower end of the PROX cooling unit 92 and is circulated upward in the PROX cooling unit 92 to cool the first and second PROX catalyst layers 83 and 84. Compared to the case where the second raw material water 93 is supplied from the upper end of the PROX cooling unit 92 and circulated downward, the entire raw material water in the PROX cooling unit 92 can be easily brought to the boiling temperature (for example, 100 ° C.). . That is, when the second raw material water 93 is supplied from the upper end of the PROX cooling unit 92, the boiled second raw material water 93 does not flow downward, but only the cold second raw material water 93 flows downward first. Therefore, it is difficult to bring the entire raw water in the PROX cooling section 92 to a uniform boiling temperature. However, when the second raw water 93 is supplied from the lower end of the PROX cooling section 92, the boiled second raw water Since 93 immediately flows upward, the entire raw material water in the PROX cooling section 92 can be easily brought to a uniform boiling temperature. For this reason, the temperature of the first and second PROX catalyst layers 83 and 84 can be easily set to a temperature suitable for the CO selective oxidation reaction.

  Further, according to the second embodiment, the PROX unit 101 converts the burner combustion exhaust gas after heating the reforming catalyst layer 18 of the fuel reforming unit 2 into the side surfaces of the first and second PROX catalyst layers 83 and 84. Since the first and second PROX catalyst layers 83 and 84 can be heated by flowing through the exhaust gas flow path 99 provided along the exhaust gas flow path 99, the heat of the burner combustion exhaust gas is effective at the time of start-up (during preheating operation). The first and second PROX catalyst layers 83 and 84 of the PROX unit 101 can be preheated.

  In particular, according to the second embodiment, the burner combustion exhaust gas is caused to flow through the exhaust gas flow path 99 of the PROX unit 101 only during the preheating operation at the time of startup by the valve 125, and the exhaust gas flow channel of the PROX unit 101 during the steady operation. 99, it is possible to prevent the burner combustion exhaust gas from flowing through 99, so that the heat generated in the PROX unit 101 (first and second PROX catalyst layers 83 and 84) flows through the PROX cooling unit 92 without being discharged together with the burner combustion exhaust gas. Since it can be used for the evaporation of the second raw material water 93, the heat dissipation loss can be reduced as compared with the case where the burner combustion exhaust gas is caused to flow through the exhaust gas flow path 99 of the PROX unit 101 even during steady operation. Note that the discharge switching means is not necessarily limited to the valve 125, and may be any means that can switch the discharge of the burner combustion exhaust gas between the preheating operation and the steady operation as described above.

  Further, as an operation method of the reformer, the burner combustion exhaust gas is caused to flow through the exhaust gas flow path 99 of the PROX unit 101 only by the valve 125 during the preheating operation at the time of startup, and during the steady operation, the exhaust gas flow channel 99 of the PROX unit 101 In order to prevent the burner combustion exhaust gas from flowing into the second raw material water flowing in the PROX cooling unit 92 without discharging the heat generated in the PROX unit 101 (first and second PROX catalyst layers 83 and 84) together with the burner combustion exhaust gas. 93 can be used for evaporation of heat, so that heat loss can be reduced compared with the case where the burner combustion exhaust gas is allowed to flow through the exhaust gas flow path 99 of the PROX cooling unit 101 even during steady operation, and after the preheating operation (each After the catalyst layer reaches a predetermined preheating temperature), supply of the mixed fluid of the first raw water 31 and the reformed fuel 105 to the first evaporator 8 and PROX It is possible to start the generation of the reformed gas to start the supply of the second source water 93 to 却部 92.

  Further, as an operation method of the reformer, during the steady operation, the maximum temperature of the reforming catalyst layer 18 of the fuel reforming unit 2 is measured, and this temperature measurement value is maintained within a predetermined temperature range. The amount of fuel supplied to the burner 11 is controlled, the vapor temperature of the mixed fluid discharged from the first evaporator 8 and supplied to the fuel reforming unit 2 is measured, and this temperature measurement value is set within a predetermined temperature range. In order to control the amount of air supplied to the burner 11 so as to be maintained within, the maximum temperature of the reforming catalyst layer 18 and the vapor temperature of the mixed fluid are reliably maintained within the respective predetermined temperature ranges. Can do.

  In the first and second embodiments, the example in which the reformed gas is supplied to the fuel cell is shown. However, the present invention is not limited to this, and the present invention contains hydrogen gas in an apparatus other than the fuel cell. The present invention can also be applied to a reformer for supplying a reformed gas.

  The present invention relates to a method for operating a reformer, and is useful when applied to, for example, downsizing and cost reduction of a reformer used in a relatively high output fuel cell.

It is sectional drawing which shows the structure of the main-body part of the reformer which concerns on Example 1 of Embodiment of this invention. It is sectional drawing which shows the structure of the CO selective oxidation part of the said reformer. It is AA arrow sectional drawing of FIG. It is a BB arrow directional cross-sectional view of FIG. It is CC sectional view taken on the line of FIG. FIG. 3 is a cross-sectional view taken along line D-D in FIG. 2. It is the E section expanded sectional view of FIG. It is a block diagram of the temperature control system with which the said reformer was equipped. It is explanatory drawing which shows the temperature gradient of a low-temperature CO conversion catalyst layer. It is sectional drawing which shows the structure of the main-body part of the reformer which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the structure of the CO selective oxidation part of the said reformer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel combustion part 2 Fuel reforming part 3 High temperature CO conversion part (HTS part)
4 Thermal insulation material 5 Water-cooled tube 5a Inlet 5b Outlet 6 Low-temperature CO conversion part (LTS part)
6a inlet 6b outlet 7 heat insulating material 8 first evaporator 8a, 8b gap 9 heat insulating material 10 second evaporator 10a gap 11 burner 12 flame 13 vertical pipe 14 end plate 15 opening 16 inner cylinder 17 outer cylinder 18 reforming catalyst layer 19 Heat insulating material 20 Exhaust gas flow path 21 Cylinder 22 Reformed gas reversal rising part 23 End plate 24 High temperature CO conversion catalyst layer (HTS catalyst layer)
25 Horizontal annular plate 25a, 25b Small hole 26 Inner cylinder 27 Outer cylinder 28, 29 End plate 30 Heat insulating material 31 First raw material water 32 Inner cylinder 33 Outer cylinder 34 Spiral tube 34a Inlet 34b Outlet 35 Ball 36a, 36b, 37a, 37b Perforated plate 38 Cylinder 39, 40 End plate 41 Hole 42, 43, 44 Exhaust gas tube 45 Tube 46 Mixing part 47 Tube 48 Mixer tube 49 Inner cylinder 50 Outer cylinder 51 Spiral tube 51a Inlet 51b Outlet 52, 53 Tubes 54, 55 End plate 56, 57 Tube 58 Header 59, 60 Tube 61 Inner cylinder 62 Outer cylinder 63 LTS cooling space 63a Inlet 63b Outlet 64 Low temperature CO shift catalyst layer (LTS catalyst layer)
65 End plate 66 Clearance 68 Tube 70 Exhaust gas tube 71 Tube 81 Inner cylinder 82 Outer cylinder 83 First PROX catalyst layer 84 Second PROX catalyst layer 85 Mixing chamber 86 First PROX air 87,88 End plate 89 Second PROX air 90 Tube 91 Cylinder 92 PROX cooling section 93 Second raw material water 94 Tube 95, 96 End plate 97 Cylinder 98 Vertical pipe 99 Exhaust gas flow path 100 Reformer main body 101 CO selective oxidation section (PROX section)
102, 103 End plate 104 Exhaust gas tube 104a Vertical tube portion 104b Horizontal tube portion 105 Reformed fuel 106 First thermometer 107 Second thermometer 108 Temperature control device 109 Fuel 110 Air 111 Fuel supply device 112 Air supply device 118 Exhaust tube 121 Tube 122 Mixer 123 Tube 124 Exhaust tube 125 Valve 125a, 125b Inflow portion 125c Outflow portion 126 Exhaust tube

Claims (24)

The reforming catalyst layer of the fuel reforming section in which the mixed steam of the reformed fuel and the raw material water flows is heated by the burner combustion exhaust gas flowing in the exhaust gas passage formed inside the fuel reforming section, thereby improving the reforming catalyst layer. In the reformer configured to generate reformed gas containing hydrogen gas by steam reforming the quality fuel,
A heat insulating material surrounding the fuel reforming section;
A water-cooled tube wound around an outer peripheral surface of a cylinder surrounding the periphery of the heat insulating material,
The raw water flowing through the water-cooled tube absorbs the heat of the fuel reforming portion transmitted from the inside of the heat insulating material to the water-cooled tube through the heat insulating material and boils. Quality equipment. The reformer according to claim 1,
Having a mixing part for mixing the reformed fuel into the boiling raw material water discharged from the water-cooled tube;
A mixed fluid evaporating means for evaporating the mixed fluid of the raw material water and the reformed fuel discharged from the mixing unit;
A reforming apparatus characterized in that the mixed fluid vapor discharged from the mixed fluid evaporation means is supplied to the fuel reforming section. The reformer according to claim 2, wherein
The mixed fluid evaporation means causes the mixed fluid of the raw material water and the reformed fuel to flow through a spiral tube provided in a double cylinder so that the inner wall surface of the double cylinder and the tube A reformer, which is a mixed fluid evaporator configured to evaporate by heating with burner combustion exhaust gas flowing through a gap therebetween. The reformer according to claim 3, wherein
The mixed fluid evaporator has a configuration in which the gap is filled with a heat transfer promoting material. In the reformer according to any one of claims 1 to 4,
A low-temperature CO conversion unit that CO converts the reformed gas generated in the fuel reforming unit, and is disposed so as to surround the water-cooled tube in a state where a gap is maintained between the reformed gas and the water-cooled tube. A reforming apparatus having a CO conversion section. The reformer according to claim 5, wherein
A reformer characterized in that the low-temperature CO shift section can be heated by flowing burner combustion exhaust gas through the gap. The reformer according to claim 6, wherein
The burner combustion exhaust gas flowing through the gap heats the reforming catalyst layer in the fuel reforming section, and further heats the mixed fluid in the mixed fluid evaporator, so that the low temperature CO shift catalyst in the low temperature CO shift section A reformer characterized in that the temperature is reduced to an intermediate temperature between the temperature of the layer and the wall surface temperature of the water-cooled tube and the cylinder, and is supplied to the gap. In the reformer according to any one of claims 5 to 7,
A high-temperature CO conversion section that CO converts the reformed gas generated in the fuel reforming section, and surrounds the periphery of the fuel reforming section, so that burner combustion exhaust gas passes through the fuel reforming section. It has a high-temperature CO transformation section that can be heated by
A reformer characterized in that the reformed gas discharged from the high-temperature CO shift section is supplied to the low-temperature CO shift section. The reformer according to claim 8, wherein
The raw water is circulated through a spiral tube provided in the double cylinder, and the reformed gas from the high-temperature CO conversion section flows through the gap between the inner wall surface of the double cylinder and the tube. It has a raw material water evaporator configured to evaporate by heating,
The raw water vapor discharged from the raw water evaporator is supplied to the fuel reforming section, and the reformed gas discharged from the raw water evaporator is supplied to the low-temperature CO conversion section. A characteristic reformer. The reformer according to claim 9, wherein
A cooling unit extending in the vertical direction along the side surface of the one or more CO selective oxidation catalyst layers arranged along the vertical direction, and supplying raw water from the lower end of the cooling unit to the inside of the cooling unit Having a CO selective oxidation part configured to cool the CO selective oxidation catalyst layer by circulating the gas upward,
A reformer characterized in that the raw water discharged from the upper end of the cooling unit is supplied to the tube of the raw water evaporator. The reformer according to claim 10, wherein
The CO selective oxidation unit causes the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming unit to flow through the exhaust gas flow path provided along the side surface of the CO selective oxidation catalyst layer, thereby the CO selective oxidation unit. A reformer characterized in that the selective oxidation catalyst layer can be heated. The reformer according to claim 1,
The mixed fluid of reformed fuel and raw material water is circulated through a spiral tube provided in a double cylinder, and burner combustion exhaust gas flowing through the gap between the inner wall surface of the double cylinder and the tube Having a mixed fluid evaporator configured to evaporate by heating;
A reforming apparatus characterized in that steam of the mixed fluid discharged from the mixed fluid evaporator is supplied to the fuel reforming section. The reformer according to claim 12, wherein
A reformer configured to flow burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming section through the gap of the mixed fluid evaporator. The reformer according to claim 12 or 13,
The mixed fluid evaporator has a configuration in which the gap is filled with a heat transfer promoting material. The reformer according to any one of claims 12 to 14,
A low-temperature CO conversion unit that CO converts the reformed gas generated in the fuel reforming unit, and is disposed so as to surround the water-cooled tube in a state where a gap is maintained between the reformed gas and the water-cooled tube. A reforming apparatus having a CO conversion section. The reformer according to claim 15, wherein
A reformer characterized in that the low-temperature CO shift section can be heated by flowing burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming section into the gap. The reformer according to claim 15 or 16,
A high-temperature CO conversion section that CO converts the reformed gas generated in the fuel reforming section, and surrounds the periphery of the fuel reforming section, so that burner combustion exhaust gas passes through the fuel reforming section. It has a high-temperature CO transformation section that can be heated by
A reformer characterized in that the reformed gas discharged from the high-temperature CO shift section is supplied to the low-temperature CO shift section. The reformer according to claim 17, wherein
The high-temperature CO conversion that flows through the gap between the inner wall surface of the double cylinder and the tube by circulating the raw water discharged from the water-cooled tube through a spiral tube provided in the double cylinder. A raw material water evaporator configured to evaporate by heating with the reformed gas from the section;
The raw water vapor discharged from the raw water evaporator is supplied to the fuel reforming section, and the reformed gas discharged from the raw water evaporator is supplied to the low-temperature CO conversion section. A characteristic reformer. The reformer according to claim 18, wherein
A cooling unit extending in the vertical direction along the side surface of the one or more CO selective oxidation catalyst layers arranged along the vertical direction, and supplying raw water from the lower end of the cooling unit to the inside of the cooling unit Having a CO selective oxidation part configured to cool the CO selective oxidation catalyst layer by circulating the gas upward,
A reformer characterized in that the raw water discharged from the upper end of the cooling unit is supplied to the water cooling tube. The reformer according to claim 19, wherein
The CO selective oxidation unit causes the burner combustion exhaust gas after heating the reforming catalyst layer of the fuel reforming unit to flow through the exhaust gas flow path provided along the side surface of the CO selective oxidation catalyst layer, thereby the CO selective oxidation unit. A reformer characterized in that the selective oxidation catalyst layer can be heated. The reformer according to claim 20, wherein
During preheating operation, burner combustion exhaust gas discharged from the gap between the water-cooled tube and the low-temperature CO conversion unit and burner combustion exhaust gas discharged from the exhaust gas passage of the CO selective oxidation unit can be discharged. A reformer comprising discharge switching means that enables discharge of burner combustion exhaust gas discharged from the mixed fluid evaporator during operation. An operation method of the reformer according to claim 11,
During the preheating operation, the burner is ignited, and the burner combustion exhaust gas is separated from the exhaust gas passage formed inside the fuel reforming unit, the gap between the low-temperature CO conversion unit and the water cooling tube, and the CO. By flowing through the exhaust gas flow path of the selective oxidation unit, the reforming catalyst layer of the fuel reforming unit, the high temperature CO conversion catalyst layer of the high temperature CO conversion unit, the low temperature CO conversion catalyst layer of the low temperature CO conversion unit, and the The CO selective oxidation catalyst layer of the CO selective oxidation unit is heated to a predetermined preheating temperature,
After this preheating operation, by starting the supply of raw water to the water cooling tube and the supply of reformed fuel to the mixing section, steam reforming of the reformed fuel in the fuel reforming section and the high temperature Starting CO conversion in the CO conversion section and the low temperature CO conversion section, and CO selective oxidation in the CO selective oxidation section, and simultaneously with the supply of the raw water to the water cooling tube or from the supply of the raw water The supply of raw material water to the cooling unit of the CO selective oxidation unit is also started later, so that the temperature of the CO selective oxidation catalyst layer of the CO selective oxidation unit and the reformed gas flowing into the low temperature CO conversion unit A method for operating a reformer, wherein the temperature is set to a predetermined temperature. The operation method of the reformer according to claim 21,
During the preheating operation, the exhaust switching unit is configured to set the burner combustion exhaust gas discharged from the gap between the water-cooled tube and the low-temperature CO conversion unit and the burner combustion exhaust gas discharged from the exhaust gas passage of the CO selective oxidation unit. The burner is ignited, and the burner combustion exhaust gas is discharged into the gap between the exhaust gas passage formed inside the fuel reforming section, the low-temperature CO conversion section, and the water cooling tube. And flowing into the exhaust gas flow path of the CO selective oxidation unit, thereby reforming the catalyst layer of the fuel reforming unit, the high temperature CO conversion catalyst layer of the high temperature CO conversion unit, and the low temperature CO conversion of the low temperature CO conversion unit. The catalyst layer and the CO selective oxidation catalyst layer of the CO selective oxidation unit are heated to a predetermined temperature,
After this preheating operation, the discharge switching means is switched to a state in which burner combustion exhaust gas discharged from the mixed fluid evaporator can be discharged, and the mixed fluid of the reformed fuel and the raw water to the mixed fluid evaporator By starting supply, steam reforming of the reformed fuel in the fuel reforming unit, CO conversion in the high temperature CO conversion unit and the low temperature CO conversion unit, and CO selective oxidation in the CO selective oxidation unit And starting the supply of raw water to the cooling section of the CO selective oxidation unit simultaneously with or behind the supply of the raw material water to the water cooling tube, A method for operating a reformer, characterized in that a temperature of a CO selective oxidation catalyst layer in a CO selective oxidation unit and a temperature of a reformed gas flowing into the low temperature CO conversion unit are set to a predetermined temperature. The operation method of the reformer according to claim 22 or 23,
During steady operation,
The maximum temperature of the reforming catalyst layer of the fuel reforming unit is measured, and the fuel supply amount to the burner is controlled so as to maintain this temperature measurement value within a predetermined temperature range,
In addition, the vapor temperature of the mixed fluid discharged from the mixed fluid evaporator and supplied to the fuel reforming unit is measured, and the temperature measurement value is maintained in a predetermined temperature range to the burner. An operation method of a reformer characterized by controlling an air supply amount.

Images