Kiln burner

Abstract

To provide a kiln burner capable of suppressing a cylindrical body from wearing out.SOLUTION: A kiln burner comprises: a first cylindrical body; a second cylindrical body arranged to house the first cylindrical body inside; a supply part provided at a base end of the second cylindrical body so as to supply solid powder, including plastic material separated from wastes through selection processing on the wastes to a space between the first cylindrical body and the second cylindrical body accompanied by gas; and a support part arranged between the first cylindrical body and the second cylindrical body so as to support the first cylindrical body on the second cylindrical body. The support part is arranged in a region on the opposite side from the supply part in the space when viewed from the first and second cylindrical bodies in a length direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to kiln burners. [Background technology]

[0002] Metals are recovered from waste such as shredder residue (sometimes referred to as "SR"), automobile shredder residue (sometimes referred to as "ASR"), and ordinary waste plastics (here, this refers to ordinary waste plastics other than SR and ASR, including, for example, municipal waste), and the plastic material is used as a thermal energy source in facilities such as factories, thereby reducing the environmental load and making effective use of the waste. For example, Patent Document 1 discloses a method for recycling SR.

[0003] The recycling method of Patent Document 1 includes heat-treating SR to embrittle it, separating the embrittled SR into small embrittled SR pieces smaller than a predetermined size by sieving or the like, removing magnetic particles from the small embrittled SR using a magnetic separator, and recovering precious metals as heavy products from the small embrittled SR after the magnetic particles have been removed using an air table. After separating the small embrittled SR from the embrittled SR by sieving or the like, the large embrittled SR is separated into metal and residue by a metal separator. The residue is used as a thermal energy source after desalination. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-034143 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if metals are not sufficiently recovered from the waste, metals may be mixed in with the plastic material separated from the waste. When such plastic material is used in, for example, a cement factory, there is a concern that the metals may collide with the cylinders that make up the kiln burner during the process of transferring the plastic material to the kiln burner, causing wear to the cylinders.

[0006] Therefore, the present disclosure describes a kiln burner that can suppress wear on the cylindrical body. [Means for solving the problem]

[0007] One example of a kiln burner includes a first cylindrical body, a second cylindrical body arranged to house the first cylindrical body, a supply unit provided at the base end of the second cylindrical body to supply a gas containing solid powder containing plastic material separated from waste by waste sorting processing to the space between the first and second cylindrical bodies, and a support unit arranged between the first and second cylindrical bodies to support the first cylindrical body relative to the second cylindrical body. The support unit is located in a region of the space opposite the supply unit when viewed in the longitudinal direction of the first and second cylindrical bodies. [Effects of the Invention]

[0008] According to the kiln burner of the present disclosure, it is possible to suppress wear on the cylindrical body. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing an example of a clinker production facility. [Figure 2] FIG. 2 is a cross-sectional view showing an example of a kiln burner. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is an enlarged view of part IV in FIG. 2, where FIG. 4(a) shows an example of the support part, and FIG. 4(b) shows another example of the support part. DETAILED DESCRIPTION OF THE INVENTION

[0010] In the following description, the same elements or elements having the same functions will be designated by the same reference numerals, and redundant explanations will be omitted. Note that in this specification, when referring to the top, bottom, right, and left of a drawing, the directions of the reference numerals in the drawing will be used as the reference.

[0011] [Cement clinker manufacturing facility] An example of a clinker production facility 1 will be described with reference to Fig. 1. The clinker production facility 1 is part of a cement production facility, and is a device for producing cement clinker MT2 from cement raw materials MT1, as illustrated in Fig. 1. The clinker production facility 1 includes an SP (suspension preheater) 10, a calciner 20, a burning section 30, and a waste treatment facility 40.

[0012] SP10 is a device that preheats the cement raw material MT1 in order to increase the efficiency of burning the cement raw material MT1 in the burning section 30. SP10 includes multiple stages (for example, about four to five stages) of cyclones 11 and a rising duct 12. The cement raw material MT1 is fed into the cyclone 11 located at the top of the SP10 tower and moves downward while passing through each stage of the cyclones 11 and the calciner 20 in sequence.

[0013] Exhaust gas from the calcination section 30 is introduced into the bottom of SP10. The exhaust gas and the cement raw material MT1 are heat exchanged sequentially in the cyclones 11 at each stage, and the cement raw material MT1 is preheated to, for example, about 850°C to become a preheated raw material. The preheated raw material produced in SP10 is discharged from the cyclone 11 located at the bottom of the tower and introduced into the calcination section 30. Meanwhile, exhaust gas G from SP10 is discharged from the cyclone 11 located at the top of SP10. The temperature of the exhaust gas G is, for example, about 400°C.

[0014] The rising duct 12 extends vertically so as to connect the calciner 20 with a kiln end 32 (described later) of the kiln 31. Therefore, exhaust gas from the firing section 30 is introduced into the calciner 20 through the rising duct 12.

[0015] The calciner 20 is provided between the lowest cyclone 11 and the firing section 30. The calciner 20 includes a calciner body 21 and a burner 22 (kiln burner). The calciner body 21 is configured to calcinate the cement raw material MT1. This improves the production volume and firing efficiency of the preheated raw materials. The calciner body 21 is connected to the kiln end 32 of the kiln 31 via a rising duct 12.

[0016] The burner 22 is connected to the calciner body 21 so as to extend horizontally. The burner 22 is configured to form a flame in the calciner body 21 using a solid powder such as pulverized coal or a finely powdered plastic material P (described later) as a thermal energy source.

[0017] The firing section 30 includes a kiln 31, a kiln bottom 32, a clinker cooler 33, and a burner 34 (kiln burner). The kiln 31 is configured to fire the preheated raw materials at high temperatures to produce cement clinker MT2. The kiln 31 may be, for example, a rotary kiln extending horizontally. The maximum temperature of the kiln 31 typically exceeds 2000°C. Therefore, the preheated raw materials are heated in the kiln 31 to, for example, about 1450°C. Exhaust gas generated inside the kiln 31 during firing is introduced into the SP10 and the calciner 20. The temperature of the exhaust gas when introduced into the SP10 and the calciner 20 is, for example, about 900°C to 1250°C.

[0018] The kiln bottom 32 is configured to introduce preheated raw materials into the kiln 31. The clinker cooler 33 is connected to the front of the kiln 31, and receives cement clinker MT2 obtained by burning the preheated raw materials in the kiln 31. The clinker cooler 33 is configured to cool the cement clinker MT2 with cooling air such as outside air. The cement clinker MT2 cooled in the clinker cooler 33 is discharged to the outside.

[0019] Burner 34 is provided in kiln 31 so as to extend horizontally in front of kiln 31. Burner 34 is configured to generate a flame within kiln 31 using a solid powder such as pulverized coal or finely powdered plastic material P (described later) as a thermal energy source. Within kiln 31, the preheated raw materials are fired by the flame of burner 34.

[0020] The waste treatment facility 40 is configured to produce plastic material P separated from the waste W by sorting the waste W. Specifically, the waste treatment facility 40 includes a crusher, a magnetic separator, a wind separator, an eddy current separator, etc. (not shown), and is configured to recover metals such as iron, stainless steel, and chromium from the waste W and to sort the plastic material P contained in the waste W. The waste W may include, for example, SR, ASR, and ordinary waste plastics. The waste treatment facility 40 may also include a vertical crusher configured to pulverize the sorted plastic material P into fine powder. The waste treatment facility 40 is configured to entrain the produced plastic material P with air and supply it to the burner 22 and / or burner 34.

[0021] [Burner configuration] Next, the configuration of the burners 22, 34 will be described with reference to Figures 2 to 4. Since the burners 22, 34 have a substantially common configuration, the burners 22, 34 will be uniformly described below by using the reference numeral "100" for both.

[0022] As illustrated in FIGS. 2 and 3, the burner 100 includes a central tube 110, cylindrical bodies 120, 130, 140, and 150, and a plurality of support portions 160.

[0023] The central tube 110 includes a plurality of flow passages (not shown) provided inside the central tube 110. The plurality of flow passages extend along the longitudinal direction Ar of the burner 100 (see FIG. 2).

[0024] The plurality of flow paths include a flow path configured to transport combustible solid waste (e.g., powdered waste plastic) by gas and spray it into the calciner main body 21 or the kiln 31. The plurality of flow paths include a flow path configured to mainly pass oil (e.g., heavy oil) for igniting the powder.

[0025] The cylindrical body 120 is disposed so as to accommodate the central tube 110 therein. That is, the cylindrical body 120 extends along the longitudinal direction Ar so as to cover the outer peripheral surface of the central tube 110. A supply pipe (not shown) is provided at the base end of the cylindrical body 120 (hereinafter, the supply pipe provided at the base end of the cylindrical body 120 will be referred to as the "supply pipe 121"). The supply pipe 121 is configured to supply gas (e.g., air) to a space V1 between the cylindrical body 120 and the central tube 110. The supply pipe 121 is connected to an upper region V1a of the space V1 as viewed from the longitudinal direction Ar. A swirl vane 122 is disposed at the tip end 120b of the cylindrical body 120. Therefore, the air ejected from the space V1 to the outside of the burner 100 forms a swirling flow.

[0026] The cylindrical body 130 (first cylindrical body) is arranged to accommodate the cylindrical body 120 therein. That is, the cylindrical body 130 extends along the longitudinal direction Ar so as to cover the outer peripheral surface of the cylindrical body 120. A supply pipe (not shown) is provided at the base end of the cylindrical body 130 (hereinafter, the supply pipe provided at the base end of the cylindrical body 130 will be referred to as the "supply pipe 131"). The supply pipe 131 is configured to supply gas (e.g., air) to a space V2 between the cylindrical body 130 and the cylindrical body 120. The supply pipe 131 is connected to an upper region V2a of the space V2 as viewed from the longitudinal direction Ar. The air ejected from the space V2 to the outside of the burner 100 forms a straight flow.

[0027] The cylindrical body 140 (second cylindrical body) is arranged to accommodate the cylindrical body 130 therein. That is, the cylindrical body 140 extends along the longitudinal direction Ar so as to cover the outer peripheral surface of the cylindrical body 130. A supply pipe (supply unit) (not shown) is provided at the base end of the cylindrical body 140 (hereinafter, the supply pipe provided at the base end of the cylindrical body 140 will be referred to as the "supply pipe 141"). The supply pipe 141 is configured to supply solid powder (pulverized coal, powdered plastic material P, etc.) accompanied by gas (e.g., air) to the space V3 between the cylindrical body 140 and the cylindrical body 130. The supply pipe 141 is connected to an upper region V3a of the space V3 as viewed from the longitudinal direction Ar. The air ejected from the space V3 to the outside of the burner 100 forms a straight flow.

[0028] The cylindrical body 150 is arranged to accommodate the cylindrical body 140 therein. That is, the cylindrical body 150 extends along the longitudinal direction Ar so as to cover the outer peripheral surface of the cylindrical body 140. A supply pipe (not shown) is provided at the base end of the cylindrical body 150 (hereinafter, the supply pipe provided at the base end of the cylindrical body 150 will be referred to as the "supply pipe 151"). The supply pipe 151 is configured to supply gas (e.g., air) to a space V4 between the cylindrical body 150 and the cylindrical body 140. The supply pipe 151 is connected to an upper region V4a of the space V4 as viewed from the longitudinal direction Ar. The air ejected from the space V4 to the outside of the burner 100 forms a straight flow.

[0029] The plurality of support portions 160 are arranged between the inner cylinder and the outer cylinder so as to support the inner cylinder relative to the outer cylinder. The plurality of support portions 160 may be separated from the supply pipes 121, 131, 141, and 151 by a distance of 3 m or less, or may be 2 m or less, in the longitudinal direction Ar. As illustrated in FIG. 2, the plurality of support portions 160 include a plurality of support portions 160A, a plurality of support portions 160B, a plurality of support portions 160C, and a plurality of support portions 160D.

[0030] The plurality of support parts 160A are arranged between the central tube 110 and the cylindrical body 120 so as to support the central tube 110 relative to the cylindrical body 120. The plurality of support parts 160A may include, for example, eight support parts 160A. The plurality of support parts 160A may include support parts 160A arranged in an upper region V1a (a region of the space V1 on the supply pipe 121 side) and support parts 160A arranged in a lower region V1b (a region of the space V1 on the opposite side from the supply pipe 121) when viewed from the longitudinal direction Ar.

[0031] The plurality of support portions 160B are disposed between the cylindrical body 120 and the cylindrical body 130 so as to support the cylindrical body 120 relative to the cylindrical body 130. The plurality of support portions 160B may include, for example, eight support portions 160B. The plurality of support portions 160B may include support portions 160B disposed in an upper region V2b (a region of the space V2 on the supply pipe 131 side) and support portions 160B disposed in a lower region V2b (a region of the space V2 on the opposite side from the supply pipe 131) when viewed from the longitudinal direction Ar.

[0032] The plurality of support parts 160C are arranged between the cylindrical body 130 and the cylindrical body 140 so as to support the cylindrical body 130 relative to the cylindrical body 140. The plurality of support parts 160C may include, for example, two support parts 160C. The plurality of support parts 160C are arranged in a lower region V3b (a region of the space V3 on the opposite side from the supply pipe 141) when viewed from the longitudinal direction Ar. In other words, the plurality of support parts 160C are not arranged in an upper region V3a (a region of the space V3 on the supply pipe 141 side).

[0033] The plurality of support portions 160D are arranged between the cylindrical body 140 and the cylindrical body 150 so as to support the cylindrical body 140 relative to the cylindrical body 150. The plurality of support portions 160D may include, for example, eight support portions 160D. The plurality of support portions 160D may include support portions 160D arranged in an upper region V4b (a region of the space V4 on the supply pipe 151 side) and support portions 160D arranged in a lower region V4b (a region of the space V4 on the opposite side from the supply pipe 151) when viewed from the longitudinal direction Ar.

[0034] Here, as illustrated in Fig. 4, the support portion 160 includes a protrusion 161 and a fitting portion 162. Although Fig. 4 illustrates the support portion 160C, the other support portions 160A, 160B, and 160D also have the same configuration as the support portion 160C.

[0035] As illustrated in Fig. 4(a), the protrusion 161 may protrude from the inner peripheral surface S1 of the cylindrical body 130 toward the cylindrical body 140. As illustrated in Fig. 4(b), the protrusion 161 may protrude from the outer peripheral surface S2 of the cylindrical body 140 toward the cylindrical body 130. The protrusion 161 may be configured so that the tip end is narrower than the base end, and may be, for example, triangular in shape.

[0036] As illustrated in Fig. 4(a), the fitting portion 162 is provided on the outer peripheral surface S2 of the cylindrical body 140, and may include a recessed groove 162a recessed toward the outer peripheral surface S2. As illustrated in Fig. 4(b), the fitting portion 162 is provided on the inner peripheral surface S1 of the cylindrical body 130, and may include a recessed groove 162a recessed toward the inner peripheral surface S1. The tip of the protrusion 161 is inserted into the recessed groove 162a, and the protrusion 161 is fitted into the fitting portion 162, whereby the cylindrical body 130 is supported and positioned relative to the cylindrical body 140.

[0037] [Effect] According to the above example, the solid powder supplied from the supply pipe 141 is carried through the space V3 entrained by the gas and reaches the tip surface of the burner 100. At this time, when viewed from the longitudinal direction Ar, the gas flows mainly through the upper region V3a and is less likely to flow through the lower region V3b. Therefore, when the support portion 160C is disposed in the lower region V3b, the gas is less likely to drift around the support portion 160C. This significantly reduces collisions between the solid powder entrained by the air and the cylindrical bodies 130 and 140. As a result, it is possible to suppress wear of the cylindrical bodies 130 and 140 while supporting the cylindrical body 130 with respect to the cylindrical body 140 by the support portion 160C.

[0038] According to the above example, the supply pipe 141 may be connected to the upper region V3a, and the support portion 160C may be disposed in the lower region V3b. In this case, the lower portion of the cylindrical body 130 is supported by the support portion 160C. Therefore, the cylindrical body 130 can be stably supported by the support portion 160C.

[0039] According to the above example, the separation distance between the supply pipe 141 and the support part 160C in the longitudinal direction Ar may be 3 m or less. In this case, the gas accompanying the solid powder flowing in from the supply pipe 141 passes between the supply pipe 141 and the support part 160C while roughly maintaining its flow velocity. Therefore, when viewed from the longitudinal direction Ar, most of the gas flows through the upper region V3a without reaching the lower region V3b. Therefore, it becomes more difficult for the gas to flow around the support part 160C, which makes it possible to further suppress wear of the cylindrical bodies 130, 140.

[0040] According to the above example, the support portion 160C may be composed of a protrusion 161 provided on one of the inner circumferential surface S1 and the outer circumferential surface S2, and a fitting portion 162 provided on the other of the inner circumferential surface S1 and the outer circumferential surface S2 and fitting with the protrusion 161. In this case, the cylindrical body 130 is supported with respect to the cylindrical body 140 by the support portion 160C simply by fitting the protrusion 161 into the fitting portion 162. Furthermore, since the protrusion 161 is fitted into the fitting portion 162 and its movement is restricted, the cylindrical body 130 is positioned with respect to the cylindrical body 140. Therefore, it is possible to realize support and positioning of the cylindrical body 140 with respect to the cylindrical body 140 with an extremely simple configuration.

[0041] [Variations] The disclosure in this specification should be considered to be illustrative in all respects and not restrictive. Various omissions, substitutions, modifications, etc. may be made to the above examples without departing from the scope and spirit of the claims.

[0042] [Experimental Example] A burner 100 according to the embodiment illustrated in FIGS. 2 and 3 and a burner according to the comparative example were installed in a kiln 31, and a clinker manufacturing facility 1 was operated. The burner according to the comparative example was the burner 100, with four support portions 160C provided in each of the upper and lower regions V3a and V3b. The initial wall thickness (before operation of the clinker manufacturing facility 1) of the cylindrical bodies 130 and 140 of the burner 100 according to the embodiment and the burner according to the comparative example was 6.0 mm. Experimental results showed that the burner according to the comparative example required maintenance once every six months because holes appeared in the cylindrical bodies 130 and 140 six months after operation of the clinker manufacturing facility 1 began due to wear. Meanwhile, the wall thickness of the cylindrical bodies 130 and 140 of the burner 100 according to the embodiment was 5.7 mm six months after operation of the clinker manufacturing facility 1 began, and the influence of wear was hardly observed. Therefore, it was confirmed that wear of the cylindrical bodies 130, 140 was sufficiently suppressed in the burner 100 according to the example.

[0043] [Other examples] Example 1. One example of a kiln burner includes a first cylindrical body, a second cylindrical body arranged to house the first cylindrical body, a supply unit provided at the base end of the second cylindrical body to supply solid powder containing plastic material separated from waste during waste sorting processing to the space between the first and second cylindrical bodies while entraining it with gas, and a support unit arranged between the first and second cylindrical bodies to support the first cylindrical body relative to the second cylindrical body. The support unit is located in the area of ​​the space opposite the supply unit when viewed from the longitudinal direction of the first and second cylindrical bodies. In this case, the solid powder supplied from the supply unit is entrained by the gas and transported through the space between the first and second cylindrical bodies, reaching the tip surface of the kiln burner. In this case, when viewed from the longitudinal direction, the gas flows mainly through the area of ​​the space on the supply unit side, and is less likely to flow through the area of ​​the space opposite the supply unit. Therefore, as in Example 1, when the support part is located in the region of the space opposite the supply part when viewed from the longitudinal direction, the gas is less likely to drift around the support part. This significantly reduces the collision between the solid powder entrained in the air and the first and second cylindrical bodies. As a result, it is possible to suppress wear on the cylindrical body while supporting the first cylindrical body against the second cylindrical body with the support part.

[0044] Example 2: In the kiln burner of Example 1, the supply unit may be connected to an upper region of the space as viewed from the longitudinal direction of the first and second cylindrical bodies, and the support unit may be disposed in a lower region of the space as viewed from the longitudinal direction of the first and second cylindrical bodies. In this case, the lower part of the first cylindrical body is supported by the support unit. Therefore, the first cylindrical body can be stably supported by the support unit.

[0045] Example 3: In the kiln burner of Example 1 or Example 2, the longitudinal separation distance between the supply section and the support section may be 3 m or less. In this case, the gas carrying the solid powder flowing in from the supply section passes between the supply section and the support section while roughly maintaining its flow velocity. Therefore, when viewed from the longitudinal direction, most of the gas flows through the area of ​​the space on the supply section side, and almost no gas flows through the area of ​​the space opposite the supply section. Therefore, it becomes more difficult for the gas to flow around the support section, making it possible to further suppress wear on the cylinder.

[0046] Example 4: In any of the kiln burners of Examples 1 to 3, the support portion may be composed of a protrusion provided on the outer peripheral surface of the first cylindrical body and a fitting portion provided on the inner peripheral surface of the second cylindrical body and fitting with the protrusion. In this case, the first cylindrical body is supported relative to the second cylindrical body by the support portion simply by fitting the protrusion into the fitting portion. Furthermore, since the protrusion is fitted into the fitting portion and movement is restricted, the first cylindrical body is positioned relative to the second cylindrical body. Therefore, it is possible to support and position the first cylindrical body relative to the second cylindrical body with an extremely simple configuration.

[0047] Example 5: In any of the kiln burners of Examples 1 to 3, the support part may be composed of a protrusion provided on the inner peripheral surface of the second cylindrical body and a fitting part provided on the outer peripheral surface of the first cylindrical body and fitting with the protrusion. In this case, the same effects as those of Example 4 can be obtained. [Explanation of symbols]

[0048] 1...clinker manufacturing equipment, 20...calciner, 22...burner (kiln burner), 30...calcining section, 34...burner (kiln burner), 40...waste treatment equipment, 100...burner, 130...cylindrical body (first cylindrical body), 140...cylindrical body (second cylindrical body), 140a...base end portion, 141...supply pipe (supply section), 160, 160B...support portion, 161...protrusion, 162...fitting portion, Ar...longitudinal direction, P...plastic material, S1...inner surface, S2...outer surface, V3...space, V3a...upper region, V3b...lower region (opposite region), W...waste.

Claims

1. A first cylindrical body; a second cylindrical body arranged to accommodate the first cylindrical body therein; a supply unit provided at a base end of the second cylindrical body to accompany a solid powder containing a plastic material separated from the waste by a waste sorting process with a gas and supply the solid powder to the space between the first cylindrical body and the second cylindrical body; a support portion disposed between the first cylinder and the second cylinder so as to support the first cylinder relative to the second cylinder, A kiln burner, wherein the support portion is arranged in a region of the space opposite to the supply portion when viewed in the longitudinal direction of the first and second cylindrical bodies.

2. the supply unit is connected to an upper region of the space when viewed from the longitudinal direction of the first and second cylindrical bodies, The kiln burner according to claim 1 , wherein the support portion is disposed in a lower region of the space when viewed in the longitudinal direction of the first and second cylindrical bodies.

3. The kiln burner according to claim 1 , wherein the distance between the supply section and the support section in the longitudinal direction is 3 m or less.

4. The support portion is composed of a protrusion provided on the outer peripheral surface of the first cylindrical body and a fitting portion provided on the inner peripheral surface of the second cylindrical body and fitting with the protrusion. A kiln burner as described in any one of claims 1 to 3.

5. The support portion is composed of a protrusion provided on the inner surface of the second cylindrical body and a fitting portion provided on the outer surface of the first cylindrical body and fitting with the protrusion. A kiln burner as described in any one of claims 1 to 3.

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