A thermal decomposition apparatus

Abstract

The present application relates to a thermal decomposition device, comprising a closed chamber, an auger shell, an auger screw, an auger speed reducer and a heater, the auger shell is provided with a feeding channel and a discharging channel at both ends along the length direction, the main body of the auger shell is located in the closed chamber, the feeding port of the feeding channel and the discharging port of the discharging channel extend out of the closed chamber respectively; the auger screw is arranged in the auger shell, for conveying the feed in the feeding channel to the discharging channel; the extended end of the auger shell extends out of the closed chamber, the auger speed reducer is installed on the extended end of the auger shell, the auger speed reducer is drivingly connected with the auger screw; the heater is arranged as a radiation source on both sides of the auger shell, for radiating and heating the auger shell in the closed chamber, the upper half surface of the auger shell is coated with a heat insulation inorganic coating layer with an absorption rate less than 0.5, and the lower half surface is electroplated with an electroplated coating layer containing black nickel. The present application effectively improves the defect of uneven thermal decomposition temperature distribution, and saves energy consumption and has a simple structure.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of material thermal decomposition, and particularly relates to a thermal decomposition device. BACKGROUND

[0002] In the existing auger pyrolysis device, the auger shell is heated by radiation heat exchange. Due to the difference in radiation angle, the radiation intensity received by the surface of the auger shell is also different, resulting in uneven heating of the outer surface of the auger. Moreover, the filling rate of the auger during operation is generally less than 0.5, and the heat demand is mainly concentrated in the lower half of the auger, while the heat absorbed by the surface of the upper half of the auger is not utilized, resulting in waste of heat. SUMMARY

[0003] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the purposes of the present application is to at least solve one or more of the above-mentioned problems in the prior art, in other words, one of the purposes of the present application is to provide a thermal decomposition device that meets one or more of the above-mentioned needs.

[0004] In order to achieve the above-mentioned purposes of the application, the following technical solutions are adopted:

[0005] A thermal decomposition device comprises a closed chamber, an auger shell, an auger screw, an auger reducer and a heater. The auger shell is provided with a feeding channel and a discharging channel at both ends along the length direction thereof, and the main body of the auger shell is located in the closed chamber. The feeding port of the feeding channel and the discharging port of the discharging channel extend out of the closed chamber, respectively. The auger screw is arranged in the auger shell and used for conveying the feed in the feeding channel to the discharging channel. The extended end of the auger shell extends out of the closed chamber, and the auger reducer is mounted on the extended end of the auger shell and is drivingly connected with the auger screw. The heater is arranged as a radiation source on both sides of the auger shell and used for radiation heating of the auger shell in the closed chamber. The upper half surface of the auger shell is coated with a heat-insulating inorganic coating layer with an absorption rate less than 0.5, and the lower half surface is electroplated with an electroplated layer containing black nickel.

[0006] As a preferred solution, the lower half surface of the auger shell is divided into several segments along the axial direction, and the black nickel plating layer of each segment has a different thickness, so that the heat exchange heat received by each segment is within a preset engineering error range.

[0007] As a preferred solution, the heat exchange heat received by each segment is the product of the radiation received by each segment and the absorption-emission ratio.

[0008] In this case, the black nickel plating layer of each segment has a different thickness, and the corresponding absorption-emission ratio is different.

[0009] The absorption-emission ratio is the ratio of the absorption rate to the emission rate of the black nickel plating layer.

[0010] As a preferred solution, the radiation amount received by each segment is:

[0011]

[0012] wherein Eb i is the radiation amount received by the i-th segment, the radiation wavelength of the radiation source λ∈(0,∞);

[0013] A coordinate system is constructed with the center of the radiation source as the origin O, the normal of the radiation surface as the X-axis, the parallel line of the auger as the Y-axis, and the normal of the XOY plane as the Z-axis. The electroplated coating layer of the i-th segment is an arc surface enclosed by four corner points A, B, C and D in a counterclockwise direction along the axial direction and the circumferential direction of the auger, and are the included angles formed by AOB and COD with XOZ respectively, θ i and θ i+1 are the included angles formed by AOC and BOD with XOY respectively, C1 and C2 are the first and second radiation constants respectively, and T is the temperature of the radiation source

[0014] As a preferred solution, the lower half surface of the auger shell is divided into segments along the axial direction.

[0015] As a preferred solution, the radiation source is installed outside the closed chamber, and the distance between the radiation source and the auger shell is not less than one order of magnitude different from the opening aperture of the closed chamber corresponding to the radiation source.

[0016] As a preferred solution, the radius of the auger shell is not less than one order of magnitude different from the distance between the radiation source and the auger shell.

[0017] Compared with the prior art, the present application has the beneficial effects that:

[0018] The thermal decomposition device of the present application not only improves the problem of uneven temperature distribution of the auger shell, but also saves energy consumption, has a simple structure, is low-carbon and environmentally friendly, easy to operate, safe and reliable. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic view of the thermal decomposition device of Example 1 of the present application;

[0020] Figure 2 is a structural schematic view of the thermal decomposition device of Example 1 of the present application from another perspective;

[0021] Figure 3 is a radiation angle schematic view of Example 1 of the present application. DETAILED DESCRIPTION

[0022] In order to more clearly illustrate the embodiments of the present application, the specific embodiments of the present application will be described below with reference to the accompanying drawings. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained from these drawings without creative labor, and other embodiments can also be obtained by those skilled in the art.

[0023] Embodiment 1:

[0024] As shown in Figure 1 and Figure 2 , the thermal decomposition device of the present embodiment includes a closed chamber 1, an auger conveyor 2 and a heater 3.

[0025] Specifically, the auger conveyor 2 includes an auger shell 20, an auger screw and an auger reducer 4, the auger shell is provided with a feeding channel and a discharging channel at both ends along the length direction of the auger shell, the main body of the auger shell is located in the closed chamber 1, the feeding port 5 of the feeding channel and the discharging port 6 of the discharging channel extend out of the closed chamber 1 respectively; the auger screw is arranged in the auger shell, which is used to convey the feed in the feeding channel to the discharging channel; the extension end of the auger shell extends out of the closed chamber, the extension end of the auger shell is installed with the auger reducer 4, the auger reducer is drivingly connected with the auger screw, and the specific installation and connection relationship of the auger conveyor can refer to the prior art, which will not be described here.

[0026] The fly ash material enters from the feeding port 5 and is output from the discharging port 6 through the auger conveyor 2, and in the transportation process, the heater 3 exchanges heat with the auger shell through radiation heat exchange.

[0027] The four heaters 3 of the present embodiment are distributed on the front and back sides of the auger shell as radiation sources, which are used to radiate and heat the auger shell in the closed chamber, that is, the two heaters on the front side mainly radiate and heat the front half of the auger shell, and the two heaters on the back side mainly radiate and heat the back half of the auger shell; wherein, the radiation source 3 is installed outside the closed chamber 1, the distance between the radiation source 3 and the auger shell 20 is different from the opening caliber 10 of the closed chamber corresponding to the radiation source by an order of magnitude, that is, the distance between the radiation source 3 and the auger shell 20 is ten times the opening caliber 10 of the closed chamber corresponding to the radiation source; the radius of the auger shell 20 is different from the distance between the radiation source 3 and the auger shell 20 by an order of magnitude, that is, the radius of the auger shell 20 is ten times the distance between the radiation source 3 and the auger shell 20.

[0028] The upper half surface 201 of the auger shell of the present embodiment is coated with a coating with an absorption rate less than 0.5, such as an inorganic coating composed of zirconium oxide and multi-element rare earth substances (cerium oxide, lanthanum oxide, etc.), and the specific product model is nano thermal insulation material JD-Y16; the lower half surface 202 has a black nickel plating layer; in this way, the heat waste of the upper half of the auger shell can be avoided.

[0029] In addition, the lower half surface 202 of the auger housing in this embodiment is divided into several segments along its axial direction, and the black nickel plating thickness of each segment is different so that the heat exchange received by each segment is approximately the same, that is, within the preset engineering error range.

[0030] Specifically, the heat exchange received by each segment is the product of the radiation received by each segment and the absorptivity-emissivity ratio; among which, the thickness of the black nickel plating layer is different for each segment, and the corresponding absorptivity-emissivity ratio is different. The absorptivity-emissivity ratio is the ratio of the absorptivity to the emissivity of the black nickel plating layer.

[0031] Since different black nickel plating thicknesses affect the absorption-emission ratio, the corresponding relationship can generally be obtained through experiments. The following are the absorption-emission ratios corresponding to several groups of black nickel platings with different thicknesses, as shown in Table 1.

[0032] Table 1 Absorption-emissivity ratios of black nickel plating layers with different thicknesses

[0033]

[0034] In this embodiment, a special coating is applied to the upper half of the auger shell to make its absorption ratio a low value, ensuring that the upper half absorbs less radiation.

[0035] Divide the lower half of the auger shell into N equal segments, and calculate the surface radiation received by each segment, Eb1, Eb2, Eb3, ..., Eb. N .

[0036] The amount of radiation received in each segment is:

[0037]

[0038] Among them, Eb i Let λ be the amount of radiation received in the i-th segment, where the radiation wavelength of the radiation source is λ∈(0,∞).

[0039] like Figure 3 As shown, a coordinate system is constructed with the center of the radiation source as the origin O, the normal to the radiation surface as the X-axis, the line parallel to the auger (i.e., the auger's axis) as the Y-axis, and the normal to the XOY plane as the Z-axis. Let the electroplated layer of the i-th segment be an arc surface enclosed counterclockwise along the auger's axis and circumference by the four corner points ABDC. This arc surface corresponds to half of the lower half of the auger's outer shell surface, divided in half along its axis. and θ represents the angles formed by AOB and COD with XOZ, respectively. i and θ i+1 The angles formed by AOC and BOD with XOY, respectively, and C1 and C2 are the first radiation constants 3.7419*10. -16 W·m 2and the second radiation constant 1.4388*10 - 2 m·K, T is the temperature of the radiation source. As shown in Figure 3 The angle distribution of the first segment I is illustrated.

[0040] The present embodiment changes the surface absorption and divergence ratio by coating a special plating layer on the lower surface of the auger shell, so that the absorption and divergence ratio of each segment of the lower half is γ1, γ2, γ3,..., γ N The product of the two is E1, E2, E3,..., E N By adjusting the thickness of the black nickel plating layer, E1 = E2 = E3,..., = E N Thus, the heat exchange heat received by each segment is consistent, thereby ensuring the temperature uniformity of the entire lower half of the auger.

[0041] Embodiment 2:

[0042] The thermal decomposition device of the present embodiment differs from that of embodiment 1 in that:

[0043] The distance between the radiation source and the auger shell and the opening aperture of the closed chamber corresponding to the radiation source differ by more than one order of magnitude, i.e., more than 10 times; the specific size can be determined according to actual needs;

[0044] Alternatively, the radius of the auger shell and the distance between the radiation source and the auger shell differ by more than one order of magnitude, i.e., more than 10 times; the specific size can be determined according to actual needs;

[0045] Other structures can refer to embodiment 1.

[0046] The above only describes the preferred embodiments and principles of the present application in detail. For ordinary skilled persons in the art, the specific implementation manner can be changed according to the idea provided by the present application, and these changes should be considered as the protection scope of the present application.

Claims

1. A pyrolysis apparatus, comprising a closed chamber, an auger shell, an auger screw, an auger reducer, and a heater, wherein the auger shell has a feed channel and a discharge channel at its two ends along its length, the main body of the auger shell is located inside the closed chamber, and the feed inlet of the feed channel and the discharge outlet of the discharge channel extend outside the closed chamber, respectively; an auger screw is provided inside the auger shell for conveying the feed from the feed channel to the discharge channel; the extended end of the auger shell extends outside the closed chamber, and an auger reducer is installed at the extended end of the auger shell, the auger reducer being driven and connected to the auger screw; the heaters, as radiation sources, are distributed on both sides of the auger shell for radiant heating of the auger shell inside the closed chamber, characterized in that... The upper half of the auger shell is coated with a heat-insulating inorganic coating with an absorption rate of less than 0.5, and the lower half is electroplated with an electroplated layer containing black nickel. The lower half of the auger shell is divided into several segments along its axial direction, with different thicknesses of black nickel plating on each segment, so that the heat exchange received by each segment is within a preset engineering error range. The heat exchanged by each segment is the product of the radiation received by each segment and the absorption-emissivity ratio. The thickness of the black nickel plating layer varies in each segment, resulting in different absorption-emission ratios. The absorption-emissivity ratio is the ratio of the absorptivity to the emissivity of the black nickel plating. The amount of radiation received by each segment is: ； Among them, Eb i The amount of radiation received in the i-th segment is the wavelength of the radiation source. ; With the center of the radiation source as the origin O, the normal to the radiation surface as the X-axis, the line parallel to the auger as the Y-axis, and the normal to the XOY plane as the Z-axis, a coordinate system is constructed. Let the electroplating layer of the i-th segment be the arc surface enclosed by the four corner points ABDC counterclockwise along the auger axis and circumference. and These are the angles formed by AOB and COD with XOZ, respectively. and Let AOC and BOD form angles with XOY respectively, C1 and C2 be the first and second radiation constants respectively, and T be the temperature of the radiation source.

2. The thermal decomposition apparatus according to claim 1, characterized in that, The lower half of the auger shell is divided into equal segments along its axial direction.

3. The thermal decomposition apparatus according to claim 1, characterized in that, The radiation source is installed outside the enclosed chamber, and the distance between the radiation source and the auger shell is not less than one order of magnitude different from the opening diameter of the enclosed chamber corresponding to the radiation source.

4. The thermal decomposition apparatus according to claim 1, characterized in that, The radius of the auger shell is at least one order of magnitude greater than the distance between the radiation source and the auger shell.

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