JPH05253463A - Plate type reformer - Google Patents

Abstract

PURPOSE:To improve reforming rate by recovering the heat of a high temp. combustion gas discharged from a combustion chamber to be utilized to reforming reaction in a reforming chamber. CONSTITUTION:An unit 1 is formed by laminating and integrating the combustion chamber 48 and the reforming chamber 40 symmetrically in upper and lower position with an interposed fuel dispersing chamber 56. The units 1 are successively laminated. A heat recovering chamber 60 is inserted between the reforming chambers 40 of the both sides of the unit 1 and is integrated. The combustion gas CG discharged from the outlet of the combustion chamber 48 is supplied to a cathode of a fuel cell through the heat recovering chamber 60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reformer for reforming a fuel gas supplied to an anode of a fuel cell from a reforming raw material gas in a fuel cell power generation system, and more particularly to a plate type reformer.

[0002]

2. Description of the Related Art A gas containing hydrocarbons such as city gas is supplied to a reformer together with steam before being supplied to a fuel cell as a fuel gas. _A reaction such as ₄ + H ₂ O → CO + 3H ₂ CO + H ₂ O → CO ₂ + H ₂ is performed to supply the reformed gas to the anode of the fuel cell.

As an example, a city gas reforming molten carbonate fuel cell power generation system using city gas as the reforming raw material gas will be described. As shown in FIG.
An electrolyte plate in which molten carbonate is impregnated into a porous substance as an electrolyte is sandwiched between a cathode (oxygen electrode) 1 and an anode (fuel electrode) 2 from both sides, and oxidizing gas is supplied to the cathode 1 side and fuel is supplied to the anode 2 side. A fuel cell FC is provided in which one cell is configured to supply gas, and each cell is stacked in multiple layers with a separator interposed therebetween. A fuel cell FC is installed in the cathode 1 of the fuel cell FC as an oxidizing gas. Is boosted by the blower 4 on the air supply line 3, preheated by the air preheater 5 and supplied to the cathode 1, and a part of the air is supplied from the branch line 6 to the combustion chamber of the reformer 7. The hot cathode outlet gas discharged from the cathode 1 is guided to the air preheater 5 through the cathode outlet gas line 8 and then discharged through the superheater 9 and the evaporator 10. A. On the other hand, as for the fuel gas supplied to the anode 2 of the fuel cell FC, after the city gas TG is pressurized by the blower 11, the natural gas preheater 12, the desulfurizer 13,
The natural gas preheater 14 is introduced into the reforming chamber of the reformer 7 for reforming to generate the fuel gas, and the fuel gas reformed in the reforming chamber is supplied to the anode 2 through the fuel gas supply line 15. And part of it is returned to the upstream side of the blower 11 that pressurizes the city gas TG.
The anode outlet gas discharged from the exhaust gas passes through the natural gas preheaters 14 and 12 through the anode outlet gas line 16, where the city gas TG is heated and then introduced into the combustion chamber of the reformer 7, thereby absorbing heat in the reformer 7. The combustion exhaust gas used as a heat source for the reaction passes through the exhaust gas line 17 and the air A flowing in the air supply line 3 together with the cathode 1
To be supplied to. Reference numeral 18 is a steam reforming steam line for converting water H ₂ O into steam in the evaporator 10 and mixing it with the city gas TG on the upstream side of the reformer 7.

As a reformer 7 for reforming a reforming raw material gas such as the above-mentioned city gas TG into a fuel gas, in recent years, it has been assumed that it is compact and capable of performing uniform combustion in the entire combustion chamber and performing effective reforming. , A plate type has been proposed.

FIG. 8 is a sectional view showing an example of a conventional plate type reformer, which is a reforming chamber 20 filled with a reforming catalyst 21.
And the combustion chamber 22 filled with the combustion catalyst 23 are laminated and integrated via a heat transfer partition plate 24, and two sets of the integrated reforming chamber 20 and the unit 25 of the combustion chamber 22 are prepared. The combustion chambers 22 are arranged so as to face each other, and an air supply chamber 26 and the air supply chamber 26 are provided between the combustion chambers 22.
Air dispersion plate 2 placed on both front and back sides to hold
The air supply dispersion unit 27 composed of 7a and 27b is sandwiched, and the air A symmetrically flows into the combustion chambers 22 through the dispersion holes 28 of the air dispersion plates 27a and 27b and enters the fuel F in the combustion chambers 22. It is configured so that it can be dispersed, and the whole is tightened with an appropriate tightening force through the upper and lower holders 29 and 30, and the whole is integrated. Reference numeral 31 is a fuel supply flow path, 32 is a combustion gas discharge flow path, 33 is a reforming raw material gas supply flow path, and 34 is a reformed gas discharge flow path.
No. 52541).

Fuel supply flow path 3 provided in the lower holder 30
1, the fuel F is supplied, the air A is supplied from an air supply passage (not shown), and the reforming raw material gas (city gas or the like) is supplied from the reforming raw material gas supply passage 23 of the upper holder 29. The reforming raw material gas is used in the reforming chamber 2 of each unit 25.
On the other hand, air A enters the air supply chamber 26, and then passes through a large number of dispersion holes 28 of the air dispersion plates 27a and 27b on both sides and separately into the combustion chambers 22 of the unit 25 as indicated by arrows. In addition, the fuel F that has been dispersed and supplied at the same time and has entered the combustion chamber 22 is burned. The heat generated by the combustion in the combustion chambers 22 is transferred to the respective reforming chambers 20 via the heat transfer partition plates 24, so that the reforming raw material gas supplied to the upper and lower reforming chambers 20 is The heat from each combustion chamber 22 causes the reforming reaction to be performed by the reforming catalyst 21 in the reforming chamber 20.

In the plate type reformer, the reforming chamber 2
In order to promote the reforming reaction at 0, the distributed combustion method is adopted so that the temperature of the outlet of the reforming chamber 20 becomes about 700 ° C. and the temperature of the outlet of the combustion chamber 22 becomes the highest. The temperature of the exhausted combustion gas is about 800 ° C. The combustion gas discharged from the combustion chamber 22 is supplied to the inlet of the cathode 1 of the fuel cell FC, but since the inlet temperature of the cathode 1 is too high at 800 ° C., the reformed fuel gas or combustion gas is used as the anode 2 or the cathode. A heat exchanger is needed to reduce each inlet temperature to 1.

The conventional plate type reformer shown in FIG. 8 is designed to disperse air and supply it to the combustion chamber 22, but depending on the system of the fuel cell plant, the fuel may be dispersed to the combustion chamber 22. There is also one that is supplied and brought into contact with the air that enters the combustion chamber 22.

[0009]

However, providing a heat exchanger for lowering the temperature of the combustion gas supplied to the cathode between the reformer and the fuel cell FC has problems in piping and is not the only problem. It is necessary to secure space, and the heat recovery of combustion gas is not used for reforming.

Therefore, the present invention is intended to provide a plate type reformer having a heat exchange function to recover the heat of the combustion gas to the reforming reaction.

[0011]

In order to solve the above problems, the present invention provides a plate type reforming chamber filled with a reforming catalyst and a plate type combustion chamber filled with a combustion catalyst with a heat transfer partition plate. Laminated through, placed with the combustion chamber side facing each other,
Further, the fuel dispersion chamber is sandwiched between both combustion chambers and laminated to form a unit, the units are laminated together, and a heat recovery chamber is formed between adjacent reforming chambers of the units. The combustion gas discharged from the combustion chamber of the unit is introduced into the heat recovery chamber, and further, the gas flowing in the reforming chamber and the gas flowing in the heat recovery chamber are in counterflow. ..

[0012]

[Function] The reforming raw material gas supplied to the reforming chamber is reformed by the reforming reaction that absorbs the combustion heat in the combustion chambers stacked through the heat transfer partition plates, and at the same time, is discharged from the combustion chamber. The discharged high-temperature combustion gas is also passed through the heat recovery chamber and heated by the sensible heat of the combustion gas from the back side of the reforming chamber to be reformed. At this time, since the gas flow in the reforming chamber and the gas flow in the combustion chamber are parallel flows, the temperature at the reforming chamber outlet can be kept high, and a high reforming rate can be obtained. Further, since the combustion gas flowing in the heat recovery chamber has a counterflow with the reformed gas,
High heat recovery rate is obtained.

[0013]

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

FIG. 1 and FIG. 2 show an embodiment of the present invention, in which a gas inlet 43 and a gas outlet 44 are diagonally formed around one surface of the heat transfer partition plate 41 as shown in FIG. The reforming chamber 4 is provided with a mask frame 42 which is formed with a notch and has a partition member 45 for preventing the outflow of the catalyst and for gas passage in parallel on both sides, and a reforming catalyst 46 is filled between the partition members 45 on both sides.
0 is formed, and the heat transfer partition plate 47 is laminated in the reforming chamber 40. As shown in FIG. 4, on the surface opposite to the heat transfer partition plate 47, a notch serving as an inlet 50 for the air A and an outlet 51 for the combustion gas CG is formed at a diagonal position for preventing catalyst outflow and also for gas passage. A mask frame 4 in which partition members 52 are provided in parallel on both sides.
9 is installed, and the combustion catalyst 53 is provided between the partition members 52 on both sides.
To form a combustion chamber 48, and a fuel dispersion plate 54 having a large number of dispersion holes 55 is superposed on the surface of a mask frame 49 forming the combustion chamber 48. The reforming chamber 4 having the above laminated structure
0 and two combustion chambers 48 are prepared, and each of the fuel distribution plates 54
They are laminated so that they face each other, and between the fuel distribution plates 54,
As shown in FIG. 5, a mask frame 57 having a notch serving as a fuel inlet 58 only on one side and having a partition member 59 for gas passage on both sides is sandwiched and integrated, and the upper and lower fuel dispersions are carried out. A unit in which the fuel dispersion chamber 56 is formed by the plate 54 and the mask frame 57 is one unit I.

As described above, a plurality of units I formed by stacking the two reforming chambers 40 and the combustion chambers 48 symmetrically with the fuel dispersion chamber 56 sandwiched therebetween are arranged so as to be stacked, and the units I are separated from each other. 6, that is, between the heat transfer partition plates 41 forming the reforming chamber 40 of each unit I, notches serving as the inlet 62 and the outlet 63 of the combustion gas CG are formed at diagonal positions, as shown in FIG. In addition, the mask frame 61 having a partition member 65 for preventing outflow and gas passage of the heat transfer accelerator (alumina ball) 64 filling the central portion is sandwiched and integrated, and the mask frame 61 and the heat transfer partition plates on both sides. A heat recovery chamber 60 is formed by 41.

Further, each reforming chamber 4 in the above unit I
The flow of the gas in 0 and the flow of the gas in the combustion chamber 48 are set to be a parallel flow, and the direction in which the combustion gas CG discharged from the combustion chamber 48 flows in the heat recovery chamber 60 is set in the reforming chamber 40. The gas inlet 62 of the heat recovery chamber 60 and the gas outlet 51 of the combustion chamber 48 of each unit I closer to the heat recovery chamber 60 are connected to each other in such a manner as to be opposed to the gas flow, and the high temperature combustion gas The sensible heat of is recovered as reforming heat.

The city gas TG as a reforming raw material gas is supplied to the inlet 43 of each reforming chamber 40 in a mixed state of steam,
Further, when the air A is supplied to the inlet 50 of each combustion chamber 48 and the fuel F is supplied to the fuel dispersion chamber 56, the fuel F flows from the fuel dispersion chamber 56 through the dispersion holes 55 of the fuel distribution plates 54 on both sides to both sides. Are uniformly dispersed and supplied to the combustion chamber 48 of the. Each combustion chamber 48 has a combustion catalyst 53, and the fuel F that has entered the combustion chamber 48 is combusted by the air A, and the combustion is performed uniformly in the entire combustion chamber 48 for each combustion chamber 48. The heat generated by the combustion in the combustion chamber 48 is transferred to the reforming chambers 40 on both sides via the heat transfer partition plates 47, and the city gas TG is reformed in the reforming chamber 40 by an endothermic reaction.

Further, the high temperature combustion gas CG discharged from the outlet 51 of each combustion chamber 48 is guided to the inlet 62 of the heat recovery chamber 60 which is in contact with the reforming chamber 40 of the upper and lower units I, and the reforming chamber 40. The sensible heat of the combustion gas CG is transferred to the reforming chamber 40 via the heat transfer partition plate 41, because the sensible heat of the combustion gas CG is made to flow in a counter-current manner with the gas flow of. As a result, the outlet 44 side of the reforming chamber 40 is maintained at a high temperature by the high temperature combustion gas entering the heat recovery chamber 60, and the reforming chamber 40 is modified by the heat from the combustion chamber 48 and the heat from the heat recovery chamber 60. Since a quality reaction is performed, a high reforming rate can be obtained. Reformed gas RG
Are supplied to the anode of the fuel cell. On the other hand, the heat recovery chamber 6
The combustion gas CG, which has been subjected to heat recovery while passing through 0, has its temperature lowered, is taken out from the outlet 63, and is supplied to the cathode of the fuel cell.

In the above embodiment, the case where the heat transfer promoting material 64 is an alumina ball is shown. However, a fin may be used, and the main flow of the combustion chamber 48 is the air A, and the fuel F from the fuel dispersion chamber 56. Although the fuel distribution system in which the fuel is supplied from the dispersion holes 55 of the fuel distribution plate 54 into the combustion chamber 48 has been illustrated, the air distribution system in which the main flow of the combustion chamber 48 is the fuel F and the dispersion gas is the air A is also possible. Good things, of course.

[0020]

As described above, according to the plate-type reformer of the present invention, the combustion chamber and the reforming chamber are stacked, and the gas inside the combustion chamber and the gas inside the reforming chamber are made to flow in parallel and the combustion gas in the combustion chamber The heat is transferred to the reforming chamber to cause an endothermic reaction of the reforming raw material gas, a heat recovery chamber is formed between the reforming chambers, and the combustion gas discharged from the combustion chamber to the heat recovery chamber. Since the heat of the combustion gas is used for the reforming reaction by flowing the gas in a counter-flow with the gas in the reforming chamber, the reforming chamber can be heated by the heat of the combustion gas from both sides. And moreover,
The temperature at the outlet of the reforming chamber can be kept high, and a high reforming rate can be obtained, and the high temperature combustion gas in the heat recovery chamber becomes a counterflow with the reforming gas to obtain a high heat recovery rate. Since the heat recovery chamber is a plate type, it is possible to achieve excellent effects such as downsizing of the whole.

[Brief description of drawings]

FIG. 1 is a side view showing an outline of a plate-type reformer of the present invention.

FIG. 2 is a perspective view showing a part of FIG. 1 in an exploded manner.

FIG. 3 is a plan view of a reforming chamber.

FIG. 4 is a plan view of a combustion chamber.

FIG. 5 is a plan view of a fuel dispersion chamber.

FIG. 6 is a plan view of the heat recovery chamber.

FIG. 7 is a schematic diagram showing an example of a fuel cell power generation system.

FIG. 8 is a sectional view of a conventional plate-type reformer.

[Explanation of symbols]

 40 reforming chamber 41 heat transfer partition plate 42 mask frame 46 reforming catalyst 47 heat transfer partition plate 48 combustion chamber 50 inlet 51 outlet 53 combustion catalyst 54 fuel dispersion plate 56 fuel dispersion chamber 60 heat recovery chamber 62 inlet 63 outlet 64 heat transfer Promotion plate I Unit A Air F Fuel CG Combustion gas TG City gas (reforming raw material gas)

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Sakae Chidori, 1-1-15 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toji Technical Center (72) Inventor Takayuki Baba 3-Matsubara, Setagaya-ku, Tokyo 27-23-104

Claims (1)

[Claims] 1. A plate-type reforming chamber filled with a reforming catalyst and a plate-type combustion chamber filling with a combustion catalyst are stacked with a heat transfer partition plate interposed therebetween, and are arranged so that the combustion chambers face each other. In addition, a plate-type fuel dispersion chamber is sandwiched between both combustion chambers to form a unit, and the units are stacked to form a plate-type heat recovery chamber between the reforming chambers between the upper and lower units. It is sandwiched and integrated, the outlet of the combustion chamber and the inlet of the heat recovery chamber are connected, and the gas of the reforming chamber and the gas of the heat recovery chamber which are in contact with each other are caused to flow in counterflow. Plate type reformer.