Resistance heating rotary hearth furnace

Abstract

The utility model provides a resistance heating rotary hearth furnace which comprises a rotary furnace bottom and a fixed furnace wall, the outer surface of the furnace wall is coated with a furnace top steel structure, a hearth space is defined by the furnace bottom and the furnace wall, and a plurality of resistance heating devices for heating materials on the furnace bottom are arranged in the hearth space. And the furnace wall is provided with a combustion-supporting air nozzle for providing combustion-supporting air into the hearth space. According to the utility model, the original burner heating mode is replaced, stable operation of atmosphere and temperature in the furnace is realized, the discharge amount of flue gas and dust in the furnace is reduced, and the environmental pollution is reduced.

Description

Technical Field

[0001] The utility model relates to a heating furnace, in particular to a resistance-heated rotary hearth furnace. Background Art

[0002] Traditional rotary hearth furnaces mostly use flue gas heating, with many burners and large flue gas flow, which leads to unstable atmosphere in the furnace and unstable temperature in each reaction section, affecting the chemical reaction process in the furnace. At the same time, excessive flue gas volume leads to more dust in the furnace, which easily blocks the outlet flue and causes environmental pollution.

[0003] Therefore, it is necessary to design a resistance-heated rotary hearth furnace to overcome the above problems. Utility Model Content

[0004] The purpose of the utility model is to overcome the defects of the prior art and provide a resistance-heated rotary hearth furnace. The utility model at least solves some of the problems in the prior art.

[0005] The utility model is achieved in this way:

[0006] The utility model provides a resistance-heated rotary hearth furnace, comprising a rotating furnace bottom and a fixed furnace wall, wherein the outer surface of the furnace wall is covered with a furnace top steel structure, the furnace bottom and the furnace wall enclose a furnace space, a plurality of resistance heating devices for heating materials on the furnace bottom are arranged in the furnace space, and a combustion air nozzle for providing combustion air to the furnace space is arranged on the furnace wall.

[0007] Furthermore, each of the resistance heating devices is installed on the inner wall of the furnace wall.

[0008] Furthermore, the resistance heating devices are arranged at intervals along the circumference of the furnace wall.

[0009] Furthermore, there are a plurality of combustion-supporting air nozzles, and each of the combustion-supporting air nozzles is arranged in an area of ​​the furnace wall where a resistance heating device is provided.

[0010] Furthermore, the resistance heating device is located directly above the furnace bottom.

[0011] Furthermore, a smoke exhaust port is provided on the furnace wall.

[0012] Furthermore, the resistance heating device adopts iron-chromium-aluminum alloy resistance wire or nickel-chromium alloy resistance wire.

[0013] Furthermore, a furnace bottom mechanical rotating device for driving the furnace bottom to rotate is provided at the bottom of the furnace bottom.

[0014] The utility model has the following beneficial effects:

[0015] The utility model provides a resistance-heated rotary hearth furnace, which replaces the original burner heating method, realizes the stable operation of the atmosphere and temperature in the furnace, reduces the emission of smoke and dust in the furnace, and reduces environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A cross-sectional view of a resistance-heated rotary hearth furnace provided in an embodiment of the utility model;

[0018] Figure 2 A schematic diagram of the distribution of the resistance heating device provided in an embodiment of the utility model within the furnace wall.

[0019] In the figure: 1. furnace bottom mechanical rotating device, 2. furnace bottom, 3. furnace wall (furnace body masonry), 4. resistance heating device, 5. furnace top steel structure, 6. combustion air nozzle, 7. smoke exhaust port. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] like Figure 1-Figure 2 The embodiment of the utility model provides a resistance-heated rotary hearth furnace, comprising a rotating furnace bottom 2 and a fixed furnace wall 3, the outer surface of the furnace wall 3 is covered with a furnace top steel structure 5, the furnace bottom 2, the furnace wall 3 and the furnace top steel structure 5 constitute a furnace body, the furnace bottom 2 and the furnace wall 3 enclose a closed furnace space, the annular seam between the furnace wall 3 and the furnace bottom 2 is sealed by a water seal device, which is a prior art and will not be repeated here, a plurality of resistance heating devices 4 for heating the material on the furnace bottom 2 are arranged in the furnace space, and a combustion air nozzle 6 for providing combustion air to the furnace space is arranged on the furnace wall 3. A furnace bottom mechanical rotating device 1 for driving the furnace bottom 2 to rotate is arranged at the bottom of the furnace bottom 2. The utility model provides a resistance-heated rotary hearth furnace, which replaces the original burner heating method, realizes the stable operation of the atmosphere and temperature in the furnace, and does not affect the chemical reaction process in the furnace. The utility model reduces the emission of smoke and dust in the furnace and reduces environmental pollution.

[0022] like Figure 2 , each of the resistance heating devices 4 is installed on the inner wall of the furnace wall 3, and both ends of the resistance heating device 4 are fixed on the inner wall of the furnace wall 3. Each of the resistance heating devices 4 is arranged at intervals along the circumference of the furnace wall 3. The resistance heating device 4 is located directly above the furnace bottom 2. The resistance heating device 4 uses an iron-chromium-aluminum alloy resistance wire or a nickel-chromium alloy resistance wire. The resistance heating device 4 uses the thermal effect of electric current passing through the resistance wire to heat the material in the furnace in a radiation manner, and the resistance heating device 4 uses existing commercially available equipment. There are a number of combustion-supporting air nozzles 6, and each of the combustion-supporting air nozzles 6 is arranged in the area of ​​the furnace wall 3 where the resistance heating device 4 is provided. In the heating section, by supplying combustion-supporting air into the furnace, the CO produced by the chemical reaction in the furnace is burned to heat the material. A smoke exhaust port 7 is provided on the furnace wall 3.

[0023] A combustion air nozzle 6 is arranged at a local position of the heating section of the furnace wall 3 (the heating section is the section for heating the material). Figure 2 The angle at which the combustion air nozzle 6 covers the annular space of the furnace wall 3 is about 10 to 30 degrees.

[0024] In this embodiment, a distributor is provided at the charging port, and a spiral discharger is provided at the discharging port; the material is delivered to the furnace bottom 2 by the distributor, and the rotation of the furnace bottom 2 drives the material into the heating section of the furnace wall 3, and the material on the furnace bottom 2 is finally discharged by the spiral discharger. Figure 2 The distributor and the spiral discharger are both arranged at the notch position of the annular furnace wall 3. The above is the prior art and will not be repeated here.

[0025] Bulk (powder, block or spherical) materials are continuously fed into the furnace through the distributor and evenly spread on the furnace bottom 2. The material layer thickness is determined according to the process requirements and controlled by the distributor. The heated materials are spread on the furnace bottom 2, and the materials rotate with the furnace bottom 2. The materials are gradually heated in the process of rotating with the furnace bottom 2. The main heat comes from the resistance heating device 4, and part of it comes from the heat generated by the combustion of CO. The heating and chemical reaction process is completed when the materials are transferred from the charging port to the discharging port. Finally, the materials are discharged from the discharging port, and the smoke is discharged from the exhaust port 7.

[0026] The utility model provides a resistance-heated rotary hearth furnace, and its preferred specific implementation is as follows Figure 1-Figure 2 As shown, the furnace body comprises a furnace bottom 2, a furnace wall 3 and a furnace top steel structure 5. The furnace body can be made of a steel structure as a shell, lined with refractory materials and heat-insulating materials, etc. The annular gap between the furnace wall 3 and the furnace bottom 2 is sealed by a water seal device, so that a closed furnace space is formed between the furnace bottom, the furnace wall and the furnace top. A resistance heating device 4 is arranged in the furnace space, and the furnace bottom 2 is driven to rotate by a furnace bottom mechanical rotating device 1.

[0027] The rotary hearth furnace is an annular structure. The furnace body consists of a rotating furnace bottom and a fixed furnace wall and furnace top. The furnace bottom 2 is driven to rotate by the furnace bottom mechanical rotating device 1. The heated material is laid on the furnace bottom 2. The bulk material is in a stationary state relative to the furnace bottom 2. The bulk material rotates with the furnace bottom 2, and the heating and chemical reaction process is completed in the process of transferring from the charging port to the discharging port. The annular gap between the furnace wall 3 and the furnace bottom 2 is sealed by a water seal device to isolate the furnace from the atmosphere. The rotary hearth furnace is provided with a plurality of resistance heating devices 4 to heat the material in the furnace in a radiation manner. In the heating section, by supplying combustion-supporting air into the furnace, the CO generated by the chemical reaction in the furnace is burned to heat the material. The utility model can be widely used in the heating and chemical reaction treatment of various powdery, blocky and spherical materials in a protective atmosphere or an atmosphere formed by self-volatilization.

[0028] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0029] 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 principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A resistance-heated rotary hearth furnace, characterized in that: It includes a rotating furnace bottom and a fixed furnace wall. The outer surface of the furnace wall is covered with a furnace top steel structure. The furnace bottom and the furnace wall enclose a furnace space. The furnace space is provided with a plurality of resistance heating devices for heating the material on the furnace bottom. The furnace wall is provided with a combustion air nozzle for providing combustion air to the furnace space.

2. The resistance-heated rotary hearth furnace of claim 1, wherein: Each of the resistance heating devices is installed on the inner wall of the furnace wall.

3. The resistance-heated rotary hearth furnace of claim 2, wherein: The resistance heating devices are arranged at intervals along the circumference of the furnace wall.

4. The resistance-heated rotary hearth furnace of claim 3, wherein: There are a plurality of combustion-supporting air nozzles, each of which is arranged in an area of ​​the furnace wall where a resistance heating device is provided.

5. The resistance-heated rotary hearth furnace of claim 2, wherein: The resistance heating device is located directly above the furnace bottom.

6. The resistance-heated rotary hearth furnace of claim 1, wherein: A smoke exhaust port is provided on the furnace wall.

7. The resistance-heated rotary hearth furnace of claim 1, wherein: The resistance heating device adopts iron-chromium-aluminum alloy resistance wire or nickel-chromium alloy resistance wire.

8. The resistance-heated rotary hearth furnace of claim 1, wherein: The bottom of the furnace bottom is provided with a furnace bottom mechanical rotating device for driving the furnace bottom to rotate.

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