Novel gas catalytic infrared emitter

Abstract

The invention discloses a novel fuel gas catalytic infrared emitter, and belongs to the technical field of equipment manufacturing. The device comprises an air pipe, a gas pipe, a premixing chamber, a mixed gas supply pipeline, a device base body, a heat preservation layer, a preheating device, a reaction layer and a protective net. The air pipe and the gas pipe are connected to the premixing chamber, the premixing chamber is connected with the device base body through a plurality of gas inlets of a mixed gas supply pipeline, the protective net is arranged on the device base body, the preheating device is arranged on the device base body, the heat preservation layers are arranged on the two sides of the preheating device, the reaction layer is communicated with the heat preservation layers, and the gas pipe is connected with the reaction layer. The protective net is arranged on the side close to the protective net. Compared with a traditional method that air and fuel gas are mixed in a combustion chamber, the average temperature and the highest temperature of the catalytic infrared emitter are remarkably improved, and the standard deviation is remarkably reduced.

Description

Technical Field

[0001] The invention specifically relates to a novel gas catalytic infrared emitter, belonging to the technical field of equipment manufacturing. Background Art

[0002] Catalytic infrared radiation is an emerging flameless combustion heating method. Its basic principle is that the combustible gas and oxygen in the air undergo an oxidation reaction under the catalysis of precious metals (also known as catalytic combustion), while radiating infrared rays. It has the characteristics of low energy consumption, fast heating and low pollution, and is therefore widely recognized internationally.

[0003] The contact mode between the combustible gas and the oxygen in the air has an important influence on the efficiency of catalytic combustion. According to the different contact modes, there are currently two ways to design catalytic infrared emitters: one is that the gas is fed from the back of the emitter and meets the heated and rising air on the surface of the front of the emitter, and catalytic combustion occurs (utility model patent, ZL201320057324.X); the other way is to use the Venturi effect, and the gas is injected into the inside of the emitter at a certain pressure while bringing in the air in the environment, so that the air and gas are mixed inside the combustion chamber and flow through the surface catalytic layer to cause catalytic combustion (its structure is similar to the utility model patent CN201821661718.8). Relatively speaking, the combustion efficiency of the second method is greatly improved, but there are still problems such as low heat conversion rate and uneven temperature distribution, which limit the performance improvement of catalytic infrared heating technology. To this end, the present invention has been improved and designed, and a technical solution of pre-mixing air and gas in a certain proportion before catalytic combustion is proposed. Summary of the invention

[0004] The present invention aims to improve the heat conversion rate of the catalytic infrared emitter and the uniformity of the emitter surface temperature, and provides a new type of catalytic infrared emitter, including an air pipe, a gas pipe, a premixing chamber, a mixed gas supply pipeline, a device base, a thermal insulation layer, a preheating device, a reaction layer and a protective net. The air pipe and the gas pipe are connected to the premixing chamber, the premixing chamber is connected to the device base through multiple air inlets of the mixed gas supply pipeline, the protective net is placed on the device base, the preheating device is arranged on the device base, the thermal insulation layer is arranged on both sides of the preheating device, and the reaction layer is connected to the thermal insulation layer and is arranged on the side close to the protective net. The air passing through the air pipe and the gas passing through the gas pipe are mixed in the premixing chamber, and enter the air inlet at the back of the device base through the mixer supply pipeline. The mixed gas is then evenly dispersed when passing through the thermal insulation layer in the device base, and flows through the preheating device for heating and then passes through the reaction layer for catalytic reaction.

[0005] The diameter of the mixed gas supply pipeline is 5-15mm, the number of air inlets is 6-12, and they are evenly distributed on the bottom plate of the device base; the distance between the axis of the heating tube body of the preheating device and the device base is 10-35mm, the diameter of the tube is 5-12mm, and it is installed on the device base; the protective net is arranged on the device base; the thermal insulation layer is aluminum silicate fiber with a thickness of 15-20mm, the distance from the device base is 10-20mm, and it is arranged on both sides of the preheating device; the reaction layer is γ-alumina fiber loaded with metal platinum, with a thickness of 4-6mm, which is connected to the thermal insulation layer and is arranged on the side of the thermal insulation layer close to the protective net.

[0006] In order to ensure that the fuel gas and the air are fully mixed, preferably, the mixed gas supply pipeline is connected with a premixing chamber.

[0007] In order to ensure that the mixed gas is evenly distributed on the reaction layer, preferably, a plurality of evenly distributed mixed gas supply pipelines are provided.

[0008] Since flameless combustion requires the reaction layer to reach 200° C., preferably, a preheating device is provided next to the reaction layer.

[0009] Beneficial effects: The present invention discloses a new type of catalytic infrared emitter, which changes the mixing method of gas and air in the traditional emitter, premixes the gas and air in the premixing chamber outside the combustion chamber, optimizes the structure and size of the emitter, saves the cost of the catalytic infrared emitter, and improves the heat conversion rate of the catalytic infrared emitter and the uniformity of the emitter surface temperature. At the same time, the emitter uses a fan to premix a rated amount of air outside the combustion chamber, which is not limited by the oxygen content of the use environment, and avoids the risk of gas leakage due to insufficient oxygen content in the environment and incomplete catalytic reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a main schematic diagram of a new type of catalytic infrared emitter;

[0011] Figure 2 It is a top view schematic diagram of a new type of catalytic infrared emitter;

[0012] Figure 3 It is a cross-sectional view of a new type of catalytic infrared emitter.

[0013] In the figure: 1. air pipe; 2. gas pipe; 3. premixing chamber; 4. mixed gas supply pipeline; 5. device base; 6. protective net; 7. preheating device; 8. insulation layer; 9. reaction layer.

[0014] Figure 4 This is the structure diagram of the traditional catalytic infrared emitter

[0015] In the figure: 1. Electric heating tube; 2. Reaction layer; 3. Insulation layer; 4. Shell; 4. Gas nozzle. DETAILED DESCRIPTION

[0016] In order to deepen the understanding of the present invention, the present invention is further described in detail below in conjunction with embodiments and drawings. The embodiments are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0017] like Figure 1 , Figure 2 and Figure 3 As shown, a novel catalytic infrared emitter includes an air pipe 1, a gas pipe 2, a premixing chamber 3, a mixed gas supply pipeline 4, a device base 5, a protective net 6, a preheating device 7, a thermal insulation layer 8 and a reaction layer 9. The air pipe 1 and the gas pipe 2 are connected to the premixing chamber 3, the premixing chamber 3 is connected to the mixed gas supply pipeline 4, a plurality of air inlets of the mixed gas supply pipeline 4 are evenly distributed on the device base 5, the protective net 6 is placed on the device base 5, the preheating device 7 is arranged on the device base 5, the thermal insulation layer 8 is arranged on both sides of the heating tube body of the preheating device 7, and the reaction layer 9 is connected to the thermal insulation layer 8 and is arranged close to the protective net 6.

[0018] Working conditions: Since the flameless combustion of gas requires the preheating temperature to reach 200°C, the reaction layer 9 needs to be preheated before the gas is introduced, and the temperature on the reaction layer 9 is measured by a thermocouple (not shown in the figure). When the temperature in the reaction layer reaches the reaction temperature, the preheating is stopped, the hand valve (not shown in the figure) and the air pump on the gas tank are opened, and the air and gas are respectively sent into the premixing chamber 3 through the air pipe 1 and the gas pipe 2, and the air and gas flow out after being fully mixed, and are evenly sent into the combustion chamber of the catalytic infrared emitter through multiple branches of the mixed gas supply pipeline 4, flow through the insulation layer 8, and enter the preheated reaction layer 9 to cause flameless combustion and emit infrared rays.

[0019] Example

[0020] The traditional catalytic infrared emitter ( Figure 4 ) as a control example. The distance between the main axis of the electric heating tube 1 of the preheating device and the device base is 12mm, and the tube diameter is 6mm; the insulation layer 3 is aluminum silicate fiber, with a thickness of 15mm, and the distance from the device base is 10mm; the reaction layer 2 is γ-alumina fiber loaded with metal platinum, with a thickness of 4mm. The intake volume of liquefied petroleum gas is 1.3SLPM. After ventilation at an air-fuel ratio of 23.3, catalytic combustion is carried out. The average temperature of the emitter surface is 430℃, the maximum temperature is 564℃, and the standard deviation is 58.4.

[0021] Embodiment 1:

[0022] The diameter of the mixed gas supply pipeline 4 is 15mm, and the number of air inlets is 6; the distance between the main axis of the heating tube of the preheating device 7 and the device base 5 is 12mm, and the diameter is 6mm; the insulation layer 8 is aluminum silicate fiber, with a thickness of 15mm, and a distance of 10mm from the device base 5; the reaction layer 9 is γ-alumina fiber loaded with metal platinum, with a thickness of 4mm. The intake volume of liquefied petroleum gas is 1.3SLPM, and after ventilation according to the air-fuel ratio of 23.3, catalytic combustion is carried out, and the average temperature of the emitter surface is 470℃, the highest temperature is 569℃, and the standard deviation is 46.7.

[0023] Embodiment 2:

[0024] The diameter of the mixed gas supply pipeline 4 is 10mm, and the number of air inlets is 8; the distance between the main axis of the heating tube of the preheating device 7 and the device base 5 is 20mm, and the diameter is 9mm; the insulation layer 8 is aluminum silicate fiber, with a thickness of 18mm, and a distance of 15mm from the device base 5; the reaction layer 9 is γ-alumina fiber loaded with metal platinum, with a thickness of 5mm. The intake volume of liquefied petroleum gas is 1.3SLPM, and after ventilation according to the air-fuel ratio of 23.3, catalytic combustion is carried out, and the average temperature of the emitter surface is 518℃, the highest temperature is 617℃, and the standard deviation is 45.4.

[0025] Embodiment 3:

[0026] The diameter of the mixed gas supply pipeline 4 is 5mm, and the number of air inlets is 12; the distance between the main axis of the heating tube of the preheating device 7 and the device base 5 is 35mm, and the diameter is 12mm; the insulation layer 8 is aluminum silicate fiber, with a thickness of 20mm, and a distance of 20mm from the device base 5; the reaction layer 9 is γ-alumina fiber loaded with metal platinum, with a thickness of 6mm. The intake volume of liquefied petroleum gas is 1.3SLPM, and after ventilation according to the air-fuel ratio of 23.3, catalytic combustion is carried out, and the average temperature of the emitter surface is 566℃, the highest temperature is 665℃, and the standard deviation is 44.1.

[0027] Table 1 Comparison of results of the embodiments

[0028]

[0029]

[0030] It can be seen from Table 1 that, compared with the traditional method, the average temperature and the maximum temperature of the catalytic infrared emitter of the present invention are significantly improved, and the standard deviation is significantly reduced.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A new type of gas catalytic infrared emitter, characterized in that: The invention comprises an air pipe, a gas pipe, a premixing chamber, a mixed gas supply pipeline, a device base, a heat-insulating layer, a preheating device, a reaction layer and a protective net, wherein the air pipe and the gas pipe are connected to the premixing chamber, the premixing chamber is connected to the device base through a plurality of air inlets of the mixed gas supply pipeline, the protective net is placed on the device base, the preheating device is arranged on the device base, the heat-insulating layer is arranged on both sides of the preheating device, the reaction layer is connected to the heat-insulating layer and is arranged on a side close to the protective net; the air passing through the air pipe is mixed with the gas passing through the gas pipe in the premixing chamber, enters the air inlet at the back of the device base through the mixer supply pipeline, the mixed gas is evenly dispersed when passing through the heat-insulating layer in the device base, flows through the preheating device for heating and then passes through the reaction layer for catalytic reaction.

2. A novel gas catalytic infrared emitter according to claim 1, characterized in that The gas and air must be fully mixed outside the launcher and then introduced into the launcher.

3. A novel gas catalytic infrared emitter according to claim 1, characterized in that The diameter of the mixed gas supply pipeline is 5-15 mm, the number of air inlets is 6-12, and they are evenly distributed on the bottom plate of the device base.

4. A novel gas catalytic infrared emitter according to claim 1, characterized in that The distance between the axis of the heating tube body of the preheating device and the device base is 10-35 mm, and the tube diameter is 5-12 mm.

5. A novel gas catalytic infrared emitter according to claim 1, characterized in that The heat-insulating layer is aluminum silicate fiber, with a thickness of 15-20 mm and a distance of 10-20 mm from the device base.

6. A novel gas catalytic infrared emitter according to claim 1, characterized in that The reaction layer is γ-alumina fiber loaded with metal platinum, and has a thickness of 4-6 mm.

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