Hot air device

Abstract

The utility model belongs to the technical field of refractory product processing, and relates to a hot air device which comprises a preheating part, a flue gas processing part and a heating part which are sequentially connected, and the preheating part comprises an inner air pipe and an outer branch pipe which are coaxially arranged and are respectively used for introducing flue gas and cold air; the flue gas treatment part comprises a metal pipe and a graphite pipe arranged in the metal pipe, one end of the graphite pipe is connected with the inner air pipe, the other end of the graphite pipe extends out of the metal pipe, three-way catalytic honeycomb ceramics are arranged in the graphite pipe, the surface layer of the graphite pipe is coated with a compact zirconia ceramic coating, and the surface layer of the graphite pipe is coated with a ceramic coating. The heating part comprises a metal pipe, microwave emitters are arranged outside the metal pipe, the heating part comprises an air outlet pipe connected with the metal pipe, a plurality of heating rods are arranged in the air outlet pipe in the axial direction of the air outlet pipe, and a plurality of microwave emitters are arranged on the outer side of the air outlet pipe. The hot air device separates flue gas from cold air, only heat exchange is carried out, water vapor in the flue gas is prevented from being mixed in, and the heat exchange efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of refractory product processing technology, and in particular to a hot air device. Background Technology

[0002] Dense shaped refractory semi-finished products contain a certain amount of volatile matter and need to be dried or dried and then fired before use. The drying of refractory products generally uses the flue gas generated by the combustion of natural gas or water gas to bake the brick blanks in a baking chamber. The exhaust gas extracted during baking is treated by water washing and photocatalytic decomposition before being discharged into the atmosphere. When the air humidity is high and the heat storage is large, coupled with the large amount of water vapor generated by the combustion of natural gas, the drying efficiency of the semi-finished products is low. The flue gas generated by combustion has a high humidity and carries a large amount of heat when discharged, which reduces the energy utilization efficiency. Therefore, this utility model proposes a hot air device. Summary of the Invention

[0003] The main purpose of this utility model is to provide a hot air device that uses an inner air duct and an outer air duct arranged coaxially, and introduces flue gas and cold air into the inner air duct and the outer air duct respectively, separating the flue gas and cold air, allowing only heat exchange, and preventing water vapor in the flue gas from mixing into the door gap.

[0004] This utility model achieves the above-mentioned objective through the following technical solution: A hot air device includes a preheating section, a flue gas treatment section, and a heating section connected in sequence. The preheating section includes an inner air duct and an outer air duct coaxially arranged for introducing flue gas and cold air, respectively. The flue gas treatment section includes a metal pipe and a graphite tube disposed inside the metal pipe. One end of the graphite tube is connected to the inner air duct, and the other end of the graphite tube extends out of the metal pipe. A three-way catalytic honeycomb ceramic is disposed inside the graphite tube, and a dense zirconia ceramic coating is applied to the surface of the graphite tube. A microwave transmitter is disposed outside the metal pipe. The heating section includes an air outlet duct connected to the metal pipe. A plurality of heating rods along its axial direction are disposed inside the air outlet duct, and a plurality of microwave transmitters are disposed outside the air outlet duct.

[0005] Preferably, multiple support plates are provided between the inner air duct and the outer air duct, and the multiple support plates are provided with openings staggered vertically.

[0006] Preferably, the air duct is provided with a plurality of metal partitions for supporting the heating rod, and a plurality of vent holes are distributed along the concentric circles of the metal partitions, and the vent holes on the same circumference of two adjacent metal partitions are staggered in the plane.

[0007] Preferably, the metal partition is a copper plate, the surface of the metal partition is coated with a corrosion-resistant coating, the heating rod is a graphite rod, and the surface of the heating rod is coated with zirconium oxide ceramic.

[0008] Preferably, the air outlet duct is covered with a heat insulation layer.

[0009] The beneficial effects of this utility model are as follows: By using an inner and outer air duct arranged coaxially, and introducing flue gas and cold air into the inner and outer air ducts respectively, the cold air is preheated through heat exchange. This avoids the problem in the prior art where mixing flue gas and cold air leads to reduced heat exchange efficiency and affects the drying of refractory products due to moisture in the flue gas. Multiple support plates separate the space inside the outer air duct, and the support plates have openings that are staggered vertically, allowing the cold air to flow through the outer air duct in a deflected manner, extending the passage time of the cold air and enhancing the heat exchange between the cold air and the flue gas. Attached Figure Description

[0010] Figure 1 This is a diagram showing the layout of the hot air device during operation in an embodiment.

[0011] Figure 2 This is a schematic diagram of a microwave transmitter.

[0012] Figure 3 yes Figure 1 Sectional view at point A.

[0013] Figure 4 yes Figure 1 Sectional view at point B.

[0014] The numbers in the image represent:

[0015] 1. Inner air duct; 2. Outer air duct; 3. Metal pipe; 4. Graphite pipe; 5. Three-way catalytic converter honeycomb ceramic; 6. Microwave transmitter; 7. Air outlet duct; 8. Heating rod; 9. Support plate; 10. Opening; 11. Metal partition; 12. Vent hole. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to specific embodiments. Example

[0017] like Figures 1 to 4As shown, a hot air device of this utility model includes a preheating section, a flue gas treatment section, and a heating section connected in sequence. The preheating section includes an inner air duct 1 and an outer air duct 2 coaxially arranged for introducing flue gas and cold air, respectively. The flue gas treatment section includes a metal pipe 3 and a graphite pipe 4 disposed inside the metal pipe 3. One end of the graphite pipe 4 is connected to the inner air duct 1, and the other end of the graphite pipe 4 extends out of the metal pipe 3. A three-way catalytic honeycomb ceramic 5 is disposed inside the graphite pipe 4, and the surface of the graphite pipe 4 is coated with a dense zirconia ceramic coating. A microwave transmitter 6 is disposed outside the metal pipe 3. The heating section includes an air outlet duct 7 connected to the metal pipe 3. A plurality of heating rods 8 are disposed inside the air outlet duct 7 along its axial direction, and a plurality of microwave transmitters 6 are disposed on the outer side of the air outlet duct 7.

[0018] Multiple support plates 9 are provided between the inner air duct 1 and the outer air duct. The multiple support plates 9 are staggered with openings 10, so that the cold air entering is deflected and moves forward in the outer air duct, prolonging the time for the cold air to pass through and enhancing the heat exchange between the cold air and the flue gas.

[0019] The duct is provided with a plurality of metal partitions 11 for supporting the heating rod 8. A plurality of vent holes 12 are distributed along the concentric circle on the metal partitions 11. The vent holes 12 on two adjacent metal partitions 11 located in the same circumference are staggered in the plane, so that the airflow forms turbulence in the duct and improves the heat exchange efficiency.

[0020] The metal partition 11 is a copper plate with high thermal conductivity. The surface of the metal partition 11 is coated with a corrosion-resistant coating. The heating rod 8 is a graphite rod. The surface of the heating rod 8 is coated with zirconium oxide ceramic to prevent the graphite rod from oxidizing at high temperatures.

[0021] The air outlet duct 7 is covered with a heat insulation layer.

[0022] The working process of this utility model is as follows: Cold air that has been dehydrated and dust-removed is introduced into the external air duct. Dust-removed flue gas is introduced from one end of the graphite tube 4. After being catalyzed by the three-way catalytic honeycomb ceramic 5, the flue gas flows to the right. The microwave transmitter 6 emits microwaves into the metal tube 3. The metal tube 3 reflects the microwaves, and the graphite tube 4 absorbs the microwaves and is rapidly heated to prevent the flue gas temperature from being too low. The cold air flows to the left along the external air duct and exchanges heat with the flue gas to preheat the cold air. The preheated cold air enters the heating section. The microwave transmitter 6 located outside the air outlet duct 7 emits microwaves into the section. The metal plate reflects the microwaves, and the graphite rod absorbs the microwaves and is heated to heat the air, thereby forming dry hot air to dry the refractory product.

[0023] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. A hot air device, characterized in that: The device includes a preheating section, a flue gas treatment section, and a heating section connected in sequence. The preheating section includes an inner air duct and an outer air duct coaxially arranged for introducing flue gas and cold air, respectively. The flue gas treatment section includes a metal pipe and a graphite tube disposed inside the metal pipe. One end of the graphite tube is connected to the inner air duct, and the other end of the graphite tube extends out of the metal pipe. A three-way catalytic honeycomb ceramic is disposed inside the graphite tube, and a dense zirconia ceramic coating is applied to the surface of the graphite tube. A microwave transmitter is disposed outside the metal pipe. The heating section includes an air outlet duct connected to the metal pipe. Multiple heating rods are disposed inside the air outlet duct along its axial direction, and multiple microwave transmitters are disposed outside the air outlet duct.

2. The hot air device according to claim 1, characterized in that: Multiple support plates are provided between the inner air duct and the outer air duct, and the multiple support plates are provided with openings that are staggered vertically.

3. A hot air device according to claim 1, characterized in that: The duct is equipped with multiple metal partitions for supporting the heating rod. Multiple ventilation holes are distributed along the concentric circles of the metal partitions, and the ventilation holes on the same circumference of two adjacent metal partitions are staggered in the plane.

4. A hot air device according to claim 3, characterized in that: The metal partition is a copper plate, and the surface of the metal partition is coated with a corrosion-resistant coating. The heating rod is a graphite rod, and the surface of the heating rod is coated with zirconium oxide ceramic.

5. A hot air device according to claim 1, characterized in that: The air outlet duct is covered with a heat insulation layer.

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