JPS6330014Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an improvement of a catalytic combustor that combusts various fuel gases using a catalyst.

[Technical background of the invention and its problems]

This type of catalytic combustor has conventionally been used in Figures 1 and 2.
The one shown in the figure is known. That is,
a is a conduction pipe, b is a catalyst, c is a preheating body, and d is a heating body. The preheating body c is a preheating gas burner in FIG. 1 and a preheating electric heater in FIG. 2, and the heating body d is a heating gas burner in FIG. 1 and a heating electric heater in FIG. 2.

In both cases, premixed fuel gas, which is a mixture of fuel gas and air in an optimum ratio, is supplied from the left end of the conduit pipe a in the figure. This premixed fuel gas is heated by the preheater c and its temperature increases. Then, the catalyst b is conducted, but the catalyst b is heated by the heating element d and reaches a high temperature, and the premixed fuel gas reacts here and is completely combusted. When the catalyst b is discharged, it is replaced with exhaust gas, and a necessary heat exchange effect is obtained at the right end of the conduit pipe a in the figure.

However, since this type of device requires two sets of heating devices, one for preheating and one for heating, the fuel consumption is high, it is not economical, and equipment such as piping and wiring and control are complicated and costly. This is a contributing factor.

[Purpose of invention]

The present invention was developed in view of the above circumstances, and its purpose is to provide a catalytic combustor that can improve economic efficiency and reduce costs by simplifying the heating structure. It is.

[Summary of the idea]

The present invention covers a conduit tube for supplying premixed fuel gas with an outer tube with a gap, fills the gap with a catalyst, and provides a heating element that burns the catalyst through the outer tube. The gas is preheated and then combusted and discharged.

[Example of idea]

An embodiment of the present invention will be described below with reference to FIG. In the figure, reference numeral 1 denotes a conduction pipe, the left end of which communicates with a fuel gas supply pipe and a combustion air supply pipe (not shown). The right end surface of the conduction tube 1 is open, and the right end portion including the open end surface 1a is covered with the outer tube 2. That is, the outer tube 2 has a diameter that leaves a gap with the conduit tube 1, and the open end surface 1a has a bottomed portion 2a with a gap, and the outer tube 2 contacts the outer peripheral surface of the conduit tube 1 to close the end surface of the outer tube 2. It has a completely sealed structure. In addition, the bottomed part 2
It is preferable that either one of the lid 2b and the lid 2b be detachable. A catalyst 3 is filled between the outer tube 2 and the outer peripheral surface of the conductive tube 1. The filling length is from a position a certain distance away from the lid 2b to a position aligned with the open end surface 1a of the conduction tube 1. Therefore, inside the outer tube 2, there is a space between the catalyst 3 and the bottomed part 2a and a space between the catalyst 3 and the bottomed part 2a.
A space chamber is formed between the and the lid body 2b, and the former is called a return space chamber 4, and the latter is called an exhaust space chamber 5. Note that an exhaust port body 6 is connected to a portion of the outer tube 2 that communicates with the exhaust space chamber 5. At the lower portion of the outer tube 2 constructed in this way, a set of gas burners 7, which are heating elements, are arranged. The gas burners 7 are positioned such that their flame holes face the catalyst 3 via the outer tube 2.

Thus, premixed fuel gas, which is a mixture of fuel gas and combustion air, is guided from the left end of the conduit pipe 1 in the direction of the arrow. When this premixed fuel gas is guided to the portion covered by the outer tube 2, it absorbs the heat of the catalyst 3 and its temperature rises. That is, the gas burners 7 perform a heating action on the outer tube 2, and the heat of the outer tube 2 is transferred to the catalyst 3, raising the temperature of the catalyst. The high heat preheats the premixed fuel gas through the conduction pipe 1. The premixed fuel gas is guided from the conduit pipe 1 to the return space 4 of the outer pipe 2, collides with the bottomed part 2a, and then passes through the catalyst 3. Here, the gas is completely combusted and is led to the exhaust port body 6 via the exhaust space chamber 5 in exchange for exhaust gas. Note that the gas absorbs heat from the outer tube 2 and rises in temperature immediately before and after being introduced into the catalyst 3, that is, also in the return space chamber 4 and the exhaust space chamber 5. Furthermore, this embodiment has the effect of making the temperature difference between the inlet side and the outlet side of the catalyst 3 very small, as shown by the solid line change A in FIG. That is, relatively low-temperature premixed fuel gas that has just been preheated is introduced into the conduit pipe 1 corresponding to the outlet side of the catalyst 3 via the exhaust space chamber 5, so that this cools the catalyst 3 and causes the catalyst 3 itself to cool. The temperature rise on the downstream side of the catalyst 3 is small, and on the contrary, in the portion corresponding to the inlet side, gas whose temperature has been sufficiently preheated and has risen is guided through the conduction pipe 1, so that positional temperature changes in the catalyst 3 are smoothed out. In comparison, in the conventional structure, the temperature difference between the inlet side and the outlet side is large, as shown by the dashed line change B in the figure. Therefore, the temperature at the outlet side increases more than necessary, and there is a risk that the catalyst itself will deteriorate and be destroyed by heat at the outlet side.

Further, when there is a change in the amount of gas burned or a change in combustion capacity due to conversion of the catalyst 3, the gas can be preheated to the required temperature by changing the overall length of the catalyst 3, and the requirement can be easily met.

In the above embodiment, a gas burner is used as the heating element 7, but the heating element 7 is not limited to this, and for example, an electric heater or other heating structure may be used.

[Effect of idea]

As explained above, in this invention, the premixed fuel gas conduit has a double pipe structure, so only one set of heating elements is required, which simplifies the heating structure and reduces operating and equipment costs. This has the effect of improving economic efficiency.

[Brief explanation of the drawing]

Figures 1 and 2 are longitudinal cross-sectional views of a catalytic combustor showing a conventional example of the present invention, Figure 3 is a vertical cross-sectional view of a catalytic combustor showing an embodiment of the present invention, and Figure 4 is a temperature of the catalyst. It is a characteristic diagram. 1... Conductive pipe, 2a... Bottomed part, 2... Outer pipe,
3... Catalyst, 7... Heating body (gas burner).

Claims (1)

[Scope of utility model registration request] A conduit tube for supplying premixed fuel gas, an outer tube having a bottomed portion facing away from the open end surface of the conduit tube, and covering a part of the outer circumferential surface of the conduit tube with a gap therebetween, and the outer tube and the conduit tube. 1. A catalytic combustor comprising: a catalyst filled between the combustor and a heating element that heats the catalyst via an outer tube.