JPS6323121B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in fuel reformers.

A fuel reformer (fuel processor) is a facility for producing hydrogen from fossil fuels, and is used in fuel cell power generation systems and the like as shown in FIG. In FIG. 1, fuel 1 is introduced into a fuel reformer 2 and converted into a gas containing hydrogen as a main component. Next, the supply gas 3 containing hydrogen as a main component is introduced into the fuel cell main body 5, and a direct current is generated by an air chemical reaction with air 4 which is separately supplied to the fuel cell main body 5. The generated DC current 6 is converted into an AC current in an AC 1 DC exchanger 7 and transmitted as AC power 8. The structure of the conventional fuel reformer is as shown in Figures 2 and 3.
FIG. 2 is a vertical cross-sectional side view of an example of a conventional fuel reformer, and FIG. 3 is a cross-sectional plan view taken along the line - in FIG. In FIG. 2, a pressure vessel 10 lined with a refractory material 9 contains a fluidized bed 11 and a double catalyst tube 1.
2, a pipe burner 13, and an upper space 14 are provided, and the fuel 16 is combusted by the combustion air 15 in the pipe burner 13, fluidizes the fluidized bed 11, heats the double catalyst tube 12, and becomes exhaust gas 17 outside the furnace. is discharged to. The raw material gas 18 is heated and reacts in the double catalyst tube 12, becomes reformed gas 19, and exits the system. The fluidized bed has good heat transfer characteristics and can be heated uniformly, so it is an excellent method for heating double catalyst tubes. However, since the temperature within the layer is uniform, the exhaust gas temperature increases. As mentioned above, in conventional fuel reforming furnaces, the fluidized bed exhaust gas is directly discharged outside the furnace without being used in any way.
The disadvantage was that the exhaust gas temperature was high and the exhaust gas heat loss was large.

In view of this current situation, the inventors of the present invention have conducted intensive research to develop a fuel reformer with low exhaust gas temperature, low exhaust gas heat loss, and high overall thermal efficiency. It has been discovered that the above object can be achieved by combining a fluidized bed and a packed bed, heating the high temperature section with the fluidized bed and heating the low temperature section with the packed bed, and based on this knowledge, the present invention was developed. This is what led to the eggplant.

That is, the present invention provides a fuel reformer that converts hydrocarbon fuel into a gas containing hydrogen as a main component.
Inside the pressure vessel, there is a fluidized bed with a combustion device installed at the bottom, a packed bed installed above the fluidized bed, and a second bed that penetrates the packed bed vertically and is positioned within the fluidized bed with its tip facing downward. The double catalyst tube has an outer tube closed at its tip, and an inner tube-outer tube flow path and an inner tube inner flow path that communicate with each other within the same tip, and at the other end. A fuel reforming device is proposed, which is connected to a raw material gas supply pipe and a reformed gas discharge pipe, and is characterized in that the exhaust gas outlet of the fluidized bed combustion device is located above the packed bed. It is something to do.

Hereinafter, embodiments of the device of the present invention will be described in detail with reference to the drawings. FIG. 4 is a longitudinal sectional side view of an embodiment of the apparatus of the present invention. In FIG. 4, 12 is an inverted double catalyst tube provided inside a pressure vessel 10 lined with a refractory material 9; 11 is a fluidized bed for heating the inverted double catalyst tube 12;
0 is a space provided above the fluidized bed 11, and 21 is a packed bed provided above the space 20 for heating the inverted double catalyst tube 12. Here, the term "inverted double catalyst tube" refers to one in which the outer tube is closed at the tip, and the flow path between the inner and outer tubes and the inner tube flow path communicate with each other within the same tip. This is a double catalyst tube arranged vertically with the tip facing downward. 13 is a pipe burner provided at the bottom of the fluidized bed, 22 is a fuel supply pipe for supplying fuel to the pipe burner, and 23 is a pressure vessel 1
0 is an air inlet provided at the bottom of the pressure vessel 10, and 24 is an exhaust gas outlet provided at the top of the pressure vessel 10. 25
26 is a raw material gas supply pipe for supplying raw material gas to the inverted double catalyst tube 12, and 26 is a reformed gas extraction pipe for extracting reformed gas from the inverted double catalyst tube 12. Examples of the filler to be filled in the packed bed include fillers such as alumina-based ceramics.
mm, outer diameter 16 mm, and hole diameter 8 mm. In the fuel reformer having such a configuration, combustion gas generated by combustion of fuel in the pipe burner 13 fluidizes the fluidized bed 11, heats the inverted double catalyst tube 12, and passes through the space 20 to the packed bed 2.
1, heats the upper part of the inverted double catalyst tube 12, and is discharged out of the system from the exhaust gas outlet 24 as exhaust gas. On the other hand, the raw material gas is supplied through the raw material supply pipe 25 into the inverted double catalyst tube 12, first heated by the packed bed 21, and then further heated by the fluidized bed 11, so that the main component is improved hydrogen. The reformed gas passes through the inner pipe of the double catalyst tube 12 and is extracted to the outside of the system via the reformed gas extraction pipe 26.

The functions and effects of the present invention will be explained below. Figure 5 shows exhaust gas in a conventional fuel reformer;
5 is an explanatory diagram showing the temperature distribution of raw material gas and reformed gas, and the left diagram in FIG. 5 is one of the conventional fuel reformer.
In the vertical side view of the example, the right figure shows the gas temperature at a location corresponding to the left figure. In the right figure, a indicates the exhaust gas temperature, b indicates the raw material gas temperature, and c indicates the reformed gas temperature. On the other hand, FIG. 6 is an explanatory diagram showing the temperature distribution of exhaust gas, raw material gas, and reformed gas in the fuel reformer of the present invention, and the left diagram in FIG. 6 is an example of the fuel reformer of the present invention. The right figure shows the gas temperature at the location corresponding to the left figure. In the figure on the right, a indicates the exhaust gas temperature, b indicates the raw material gas temperature, and c indicates the reformed gas temperature. Note that the numbers in Figures 5 and 6 refer to the 2nd
The same parts as the parts with the same numbers in FIGS. As is clear from the comparison between Figures 5 and 6, in the fuel reformer of the present invention, the exhaust gas from the fluidized bed enters the packed bed through the space and is used to heat the double catalyst tube. (1) The temperature of exhaust gas decreases.

(2) Since the exhaust gas temperature is lower, the temperatures of the raw material gas and reformed gas are lower.

(3) Since the raw material gas is heated in the packed bed and the fluidized bed, the amount of heat transferred to the fluidized bed is reduced and the temperature of the fluidized bed can be lowered.

As described above in detail, the fuel reformer of the present invention can achieve the following effects.

(1) As the exhaust gas temperature becomes lower, exhaust gas heat loss decreases and overall thermal efficiency increases.

(2) Not only exhaust gas temperature but also raw material gas, reformed gas,
Since the temperature of the fluidized bed is also lowered, the operating temperature of the equipment materials is lowered overall, the reliability of the equipment is improved, and the material cost can be reduced.

(3) By inverting the double catalyst tube, the pipe burner installed at the bottom of the fluidized bed can be freely arranged, and the maximum metal temperature of the double catalyst tube can be lowered.

As described in detail above, the present invention provides an industrially useful fuel reformer that has high thermal efficiency and is highly reliable.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the fuel cell power generation system, Figure 2
The figure is a longitudinal cross-sectional side view of an example of a conventional fuel reformer, FIG. 3 is a cross-sectional plan view taken along the - line in FIG.
FIG. 5 is an explanatory diagram of the temperature distribution of gas in a conventional fuel reformer, and FIG. 6 is a temperature distribution of gas in the fuel reformer of the present invention. FIG. 10...Pressure vessel, 11...Fluidized bed, 12...
Double catalyst tube, 13... Pipe burner, 21...
Filled bed, 22... Fuel supply pipe, 25... Raw material gas supply pipe.

Claims (1)

[Claims] 1 In a fuel reformer that converts hydrocarbon fuel into gas whose main component is hydrogen, a fluidized bed with a combustion device installed at the bottom and a packed bed installed above the fluidized bed are installed in a pressure vessel. , and a double catalyst tube that penetrates the same packed bed vertically and is positioned in the same fluidized bed with the tip facing downward. The inter-pipe flow path and the inner pipe flow path communicate with each other within the same tip and with the raw material gas supply pipe and the reformed gas extraction pipe at the other end, and the exhaust gas outlet of the fluidized bed combustion apparatus is A fuel reformer characterized in that it is located above the packed bed.