JPS62190321A - Catalytic burner - Google Patents

Abstract

PURPOSE:To enable always stabilized igniting behavior in a catalytic burner to be obtained, by providing a proper amount of combustion air to the burner by detecting the temperature in a catalyst body with a heat sensitive device and by controlling the number of revolution of a fan in accordance with the temperature detected by the heat sensitive device. CONSTITUTION:A mixing burner 3 takes in a gas from a gas nozzle 1, combustion air is fed from an air hole 2, the gas is mixed with the air in the mixing type burner 3, and the mixed gas is ignited on a burner. At the time of ignition, a catalyst body 5 is preheated up to an activated temperature by combustion heat. After that, flames on the mixing type burner 3 is once extinguished by shutting off of gas for several seconds. When the gas is flowed again, it can be self-burned by the heat of a catalyst body 5 of which temperature has already been raised up to the activated temperature. The temperature at the time of re-ignition in the catalyst body 5 is detected by a heat sensitive device 12, and the number of revolution of a fan 7 is controlled properly by a control circuit 14. The rate of combustion air can be controlled at optimum all the time by the functions of a heat sensitive device 12 and the control circuit 14 both at the initial time of ignition and at the time of re-ignition. In such a manner, stabilized igniting behavior can be assured in a catalytic burner.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is a low NOx system that uses a catalyst to cause an oxidation reaction in a mixed gas of mixed fuel and air, and uses the heat generated at this time for purposes such as heating. The present invention relates to a catalytic combustor.

(Prior Art) A conventional catalytic combustor is as shown in FIG.
A mixing burner 3 equipped with a on one side.

and an igniter 8 facing near the preheating burner 3a.

It had a gas nozzle 10 facing the other side of the mixing burner 3.

(Problems to be Solved by the Invention) According to the above configuration, at the beginning of one ignition, the preheating burner 3a of the mixing burner 3 is ignited by the igniter 8.

The catalyst body 6 is combusted to preheat the downstream catalyst body 6, and after the preheating is completed, catalytic combustion is performed using the medium 5.9 At the initial stage of ignition, the catalyst body 6 is heated by the preheating temperature of the catalyst body 5 as shown in FIG.
Since the pressure loss changes in proportion to the temperature of the catalyst body 6, the amount of combustion air decreases as the temperature of the catalyst body 6 increases. Therefore, if the amount of combustion air is adjusted to the steady state, the fuel may be too thin at the initial stage of ignition to lift and ignite, or in the case of second ignition after extinguishing, that is, when the temperature of the catalyst body 5 is between the initial stage of ignition and the steady state. There was a problem in that the amount of combustion air at the time of ignition was excessive, making stable ignition difficult.

(Means for solving problems) The present invention solves the above problems.

A heat-sensitive element is installed near the catalyst body to detect the temperature of the catalyst body, and the fan is connected to a control circuit that detects the temperature of the catalyst body using the heat-sensitive element and controls the rotation speed of the fan. ) With the above configuration, stable ignition can be achieved by controlling the combustion air to an appropriate amount even in the initial stage of one ignition or in the case of re-ignition.

(Example) An embodiment of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the present invention, in which a catalyst body 5, which is a honeycomb-shaped heat-resistant ceramic carrier coated with a high-temperature oxidation catalyst, is tightly mounted in a box-shaped heat radiator 4. Further, a mixing burner 3 having a gas nozzle 1 is built in the radiator 4 upstream of the catalyst body 5, and an igniter 8 is provided in the flame hole of the mixing burner 3. The catalyst body 5 is installed vertically, and a heat radiation wall surface 9 of the heat radiator 4 faces the catalyst body 5, and a heat sensitive element 12 is provided on this heat radiation wall surface 9. Further, an (auxiliary 77) 16 is provided at the inlet of the mixing burner 3, and the inlet of this auxiliary fan 15 serves as an air hole 2 for intake of combustion air. A fan is provided downstream of the catalyst body 6. The motor 13 of this F/7 is provided with a rotation speed detector 16.
A control circuit 14 is connected to via a heat sensitive element 12.

In the above configuration, the mixing burner 3 is injected with gas from the gas nozzle 1, and at the same time, when the fan 7 is turned, combustion air of more than theoretical air is sucked from the air hole 2, mixed by the mixing burner 3, and then ignited. Ignite it using the container 8. The catalyst body 5 is preheated to the activation temperature by the combustion heat at this time, and then the flame is extinguished by the mixing burner 3 by turning off the gas for a few seconds, and the catalyst body is heated to the activation temperature by flowing the gas again. 5.It is capable of self-combustion.

Here, in the early stage of ignition, if the temperature of the catalyst body 5 is between To and Tl, the rotation speed of the fan 7 is .

The temperature of the catalyst body 5 is detected by the heat sensitive element 12 so that the B rotation is higher than A at the temperature T1 to T2, and the C rotation is higher than B at the temperature T2 to T3, and the control circuit 14 controls the rotation speed of the fan. It is something that can be controlled. Therefore, both at the initial stage of ignition and at the time of re-ignition, the heat sensitive element 12 and the control circuit 14 always function.

The amount of combustion air can be adjusted to the optimum level, and stable ignition can be achieved at all times.

(Effects of the Invention) As described above, according to the present invention, the temperature of the catalyst is detected by the heat-sensitive element even at the initial stage of second ignition and at the time of re-ignition, and the fan rotation speed is automatically controlled based on the temperature at this time. By using an appropriate amount of combustion air.

This provides a highly safe catalytic combustor that allows stable ignition at all times.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of an embodiment of the catalytic combustor of the present invention;
FIG. 2 is a perspective view of the same essential parts, FIG. 3 is a synchronization diagram, FIG. 4 is a schematic sectional view of a conventional catalytic combustor, and FIG. 5 is a characteristic diagram thereof. 3...Mixing burner, 6...Catalyst body. 7...Fan, 12...Thermosensitive element. 14...Control circuit/

Claims (1)

[Claims] A mixing burner (3) that premixes fuel and combustion air taken in by a fan (7); and a mixing burner (3).
In a catalytic combustor equipped with a catalyst body (5) having porous holes downstream of the catalyst body (5), a heat-sensitive element (12) for detecting the temperature of the catalyst body (5) is provided near the catalyst body (5), and a fan ( A catalytic combustor characterized in that 7) is connected to a control circuit (14) that detects the temperature of the catalyst body (5) using a heat-sensitive element (12) and controls the rotation speed of the fan (7).