JP2015068147A - Drier of asphalt plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drier of an asphalt plant, in which an inclination angle of a drum can be effortlessly changed.SOLUTION: A hot hopper 7 and a cold hopper 9 are mounted on a base 3 together with a drum 2, the inclination angle of the drum 2 is freely changed by tiltably journaling a central part of the base 3 on a floor surface and supporting both end parts of the base 3 by a hydraulic cylinder 12. An exhaust flue 8 just near an outlet of the cold hopper 9 is divided into a lower flue 8a and an upper flue 8b. The lower flue 8a and the upper flue 8b are connected together in a loosely fitted condition while imparting a proper clearance between them so that an end parts of the respective flues do not abut on each other due to tilting of the base 3, an aggregate discharge chute 15 of the hot hopper 7 and an aggregate receiving hopper 16 of a bucket elevator 14 are also connected together in a loosely fitted condition, and the periphery of respective connection parts are enclosed by bellows 13 and 17, respectively.

Description

  The present invention relates to a dryer for heating and drying a new aggregate or asphalt pavement waste material in an asphalt plant for producing asphalt composite material which is a road pavement material.

  The dryer installed in the asphalt plant is carefully designed in terms of drum size, number of revolutions, shape of scraping blades, number of them, etc., and materials such as new aggregates and asphalt pavement waste materials supplied into the drum are not used. The dwell time in the drum as it rolls down in the drum is kept constant so that the material can be stably heated to the desired temperature.

  By the way, some materials such as new aggregates and asphalt pavement wastes have a high water content due to the influence of storage conditions, etc. In such a case, even if heating is normally performed with a conventional dryer, heating may be insufficient and residual moisture may increase.

  Therefore, the applicant of the present invention, for example, as shown in Patent Document 1 (Japanese Utility Model Publication No. 63-171409), a drum supported rotatably and a hot hopper or cold hopper disposed at both ends of the drum together. It has been proposed that the tilt angle of the drum on the base can be changed as appropriate by mounting the base on the base and making the base tiltable. Depending on the angle, the residence time of the material in the drum can be adjusted, thereby making it possible to freely adjust the amount of heating to the material and flexibly to various situations as described above It is thought that it can respond.

  However, in the apparatus of Patent Document 1, the hot hopper and the cold hopper disposed on both ends of the drum are mounted on the base together with the drum, and if the tilt angle of the drum can be changed, for example, A structure is required to allow tilting at a connecting portion between a tilting part such as a cold hopper and a fixed part such as an exhaust flue, but this point is not particularly mentioned.

  On the other hand, as shown in Patent Document 2 (Japanese Patent Application Laid-Open No. 2006-207225), the applicant of the present invention mounts only a drum on a tiltable base so that the drum as a rotating body is mounted. A hot hopper or cold hopper with both ends fixed is inserted, and a plurality of sealing materials such as metal seals are placed around the drum so as to surround the periphery of the drum. The end is brought into contact with the outer peripheral surface of the drum by utilizing the elasticity of the sealing material, and when the drum is rotated, the free end of the sealing material is slid while closely contacting the drum surface so that a gap is not generated as much as possible. Is preventing the invasion of. In addition, even if the tilt angle of the drum is changed, the elastic sealing material is appropriately deformed accordingly, and the free end portion comes into contact with the outer peripheral surface of the drum so that the gap for intruding outside air is eliminated. .

Japanese Utility Model Publication No. 63-171409 JP 2006-207225 A

  However, in the apparatus of Patent Document 2, an elastic sealing material is provided in the gap between the drum that is the rotating body and the fixed hot hopper or cold hopper, and its free end is brought into contact with the outer peripheral surface of the drum. Although the free end of the sealing material is slid while closely contacting the drum surface, it is assumed that the elasticity of the sealing material will be gradually lost when operated for a long period of time, resulting in a problem that the sealing performance deteriorates. There is a possibility.

  This invention makes it a subject to provide the dryer of the asphalt plant which can change the inclination-angle of a drum reasonably in view of said point.

  In order to solve the above-mentioned problems, in the dryer of the asphalt plant according to claim 1, a cylindrical drum having a large number of scraping blades is rotatably supported on the base, and one end portion of the drum is supported. In an asphalt plant dryer in which the other end is inserted into a cold hopper provided with an exhaust flue for exhaust gas discharge, the hot hopper and the cold hopper are It is mounted on the base together with the drum, and a predetermined position in the longitudinal direction of the base is pivotally supported on the floor surface, and a predetermined portion of the base is supported on the floor surface by lifting means. The tilt angle of the drum on the base is freely changeable according to the lifting / lowering operation of the lifting / lowering means, while the exhaust flue immediately adjacent to the cold hopper exit is divided into a lower flue and an upper flue, And top The road is loosely fitted with a predetermined clearance so that the ends of the flues do not come into contact with each other due to the tilting of the base, and the aggregate discharge chute of the hot hopper and the aggregate vertical transfer device The aggregate receiving hoppers are loosely fitted with a predetermined clearance so as not to contact each other due to the tilt of the base, and are connected by a cover body that can be bent and stretched. It is characterized by that.

  Further, in the dryer of the asphalt plant according to claim 2, the connecting portion between the lower flue and the upper flue has a tangential direction of a circle whose radius is a distance to the connecting portion around the pivotal support portion of the base. Inclined at a predetermined angle that is substantially parallel and loosely fitted, and when tilting the base, the lower flue of the connecting portion is swung substantially linearly with respect to the upper flue to freely fit between the flues It is characterized in that the clearance is held substantially constant.

  Further, in the asphalt plant dryer according to claim 3, the base is pivotally supported at a substantially central portion in the longitudinal direction of the base, and a plurality of pairs are provided at opposite positions on both sides of the pivot support location. It is characterized by arranging lifting means.

  Further, in the asphalt plant dryer according to claim 4, the lower flue end is loosely fitted into the upper flue end, and the outer periphery of the lower flue end surrounds the connecting portion with the opposed upper flue end. A dust trapping piece that dams up and captures the dust leaking from the clearance of the connecting portion is provided around, and a through-hole communicating with the inside of the lower flue is formed at the base end portion of the dust trapping piece to collect the dust. The dust trapped by the piece is configured to be reduced from the through hole into the lower flue.

  According to the asphalt plant dryer of claim 1 according to the present invention, the hot hopper and the cold hopper are mounted on the base together with the drum, and the base is tiltably supported on the floor surface, A predetermined part of the base is supported by lifting means, and the tilt angle of the drum can be freely changed according to the lifting operation, while the exhaust flue nearest to the cold hopper outlet is divided into a lower flue and an upper flue In addition, the hot hopper aggregate discharge chute and the aggregate vertical conveyance are connected while being loosely fitted with a predetermined clearance so that the ends of the flues do not come into contact with each other as the base tilts. The aggregate receiving hopper of the apparatus is also connected by loose fitting with a predetermined clearance so that the aggregate receiving hoppers do not come into contact with each other by tilting the base, and each of the connecting portions is surrounded by a cover body that can be bent and stretched. Made In, it can change without difficulty the inclination angle of the drum, nor for sucking the outside air from the connecting part.

  According to the asphalt plant dryer according to claim 2, the connecting portion between the lower flue and the upper flue is a tangent of a circle whose radius is the distance to the connecting portion around the pivotal support portion of the base. Each flue that is loosely fitted at a predetermined angle substantially parallel to the direction and loosely fitted by swinging the lower flue of the connecting portion substantially linearly with respect to the upper flue when the base is tilted Since the clearance between them is held substantially constant, when the base is tilted, the lower flue loosely fitted in the upper flue swings (moves) substantially linearly with respect to the upper flue. Even if the clearance between the flues is reduced, they do not come into contact with each other, and the structure of the connecting portion can be simplified such that the diameter of the upper flue can be reduced.

  According to the asphalt plant dryer according to claim 3, the base is pivotally supported at a substantially central portion in the longitudinal direction of the base, and is paired with opposing positions on both sides of the pivotal support location. Since a plurality of lifting and lowering means are arranged, the swinging width (moving width) of the lower flue that is loosely fitted to the upper flue in the immediate vicinity of the cold hopper outlet when the base is tilted and the aggregate receiving hopper of the aggregate vertical conveying device The rocking width (movement width) of the aggregate discharge chute of the fitted hot hopper is almost the same without bias, and the clearance of each connecting part can be made as small as possible to simplify the structure, and on the base The swing width (movement width) of the hot hopper and the cold hopper located at both ends of the hopper can be reduced as much as possible, and the adjustment of the connection of peripheral devices such as a material supply conveyor becomes easy. Further, the base can be supported in a well-balanced manner, and a relatively small one can be adopted as the lifting means.

  According to the asphalt plant dryer of claim 4, the lower flue end is loosely fitted in the upper flue end, and the outer flute end is connected to the opposing upper flue end. Surrounding and surrounding the dust trapping piece that dams up and captures the dust leaked from the clearance of the connecting portion, and at the base end of the dust trapping piece, a through hole communicating with the lower flue is drilled, Since the dust trapped by the dust trapping piece is reduced to the lower flue from the through hole, dust leaking from the clearance of the flue connecting part can be suppressed and the dust trapped by the dust trapping piece Can be immediately reduced into the flue.

It is a front view which shows one Example of the dryer of the asphalt plant which concerns on this invention. FIG. 2 is a partially cutaway enlarged view showing a connecting portion between a lower flue and an upper flue of the exhaust flue of FIG. 1. FIG. 2 is a partially cutaway AA sectional view of FIG. 1. It is a figure equivalent to FIG. 2 which shows another embodiment of the connection part of a lower flue and an upper flue. It is a figure equivalent to FIG. 2 which shows another embodiment. It is a figure equivalent to FIG. 2 which shows another embodiment.

  In the dryer of the asphalt plant according to the present invention, one end portion of the drum rotatably supported on the base is inserted into a hot hopper provided with a hot air supply burner, while the other end portion is used for exhaust gas derivation. In an asphalt plant dryer that penetrates into a cold hopper having an exhaust flue, the hot hopper and the cold hopper are mounted on a base together with a drum, and a substantially central portion in the longitudinal direction of the base is placed on the floor surface. The base is supported by a plurality of lifting and lowering means such as a hydraulic cylinder and a motor cylinder so as to be paired at opposite positions on both sides of the pivot support portion. The tilt angle of the drum on the base is freely changeable according to the lifting / lowering operation of the means.

  Further, the exhaust flue immediately adjacent to the cold hopper exit is divided into a lower flue and an upper flue, and the lower flue and the upper flue are loosely fitted and connected with an appropriate clearance. The connecting portion is inclined substantially parallel to the tangential direction of a circle whose radius is the distance to the connecting portion with the pivot support portion of the base as the center, and when the base is tilted, the clearance between the flues is While it is configured so that the ends of the flues are held substantially constant and the ends of each flue do not come into contact with each other, the connection between the aggregate discharge chute of the hot hopper and the aggregate receiving hopper of the aggregate vertical conveyance device is also based on They are connected by loose fitting with an appropriate clearance so that they do not come into contact with each other due to tilting of the base, and each of these connecting portions is surrounded by a cover body such as a bellows that can be bent and stretched. Between each device provided in the connecting part Or dust is scattered around from the clearance, the outside air is attempted to prevent or enter the scanner.

  When adjusting the amount of heating according to the state and characteristics of the material, for example, when increasing the amount of heating, the lifting means at both ends of the base are moved up and down to make the drum tilt angle gentler. The amount of heating is increased so that the residence time of the material in the drum is lengthened. On the other hand, in the case of reducing the heating amount, as described above, the lifting means at both ends of the base are moved up and down to adjust the drum tilt angle so that the residence time of the material in the drum is increased. Reduce the amount of heating to shorten.

  At this time, since a hot hopper and a cold hopper are mounted on the tiltable base together with the drum, the positional relationship with each hopper does not change even when the tilt angle of the drum is changed. It is possible to avoid the occurrence of problems such as a decrease in sealing performance at the fitting part with the hopper and to provide an appropriate clearance at the connecting part between the dryer and the peripheral device. Even if the support angle of the hopper or the cold hopper is changed, problems such as interference between the devices do not occur, and the tilt angle of the drum can be changed without structural undue or trouble.

  In addition, the position to pivotally support the base is not particularly limited, but the pivoting width of the hot hopper or the cold hopper when the base is tilted is suppressed by pivoting at the substantially central portion in the longitudinal direction of the base. It is possible to easily adjust the connection at each connecting portion with the peripheral device, and can support the base in a well-balanced manner, and adopt a relatively small hydraulic cylinder as a lifting means. Is possible.

  Further, the connecting portion between the lower flue and the upper flue is not particularly limited, but as described above, a tangent of a circle whose radius is the distance to the connecting portion around the pivotal support portion of the base. By tilting in parallel with the direction, the clearance between the lower flue that swings with the tilt of the base and the fixed upper flue can be kept substantially constant, and the lower flue and the upper flue It is easier to adjust the connection at the connection with the flue.

  Further, the lower flue end is loosely fitted in the upper flue end, and a substantially annular dust trapping piece capable of surrounding the connecting portion with the opposite upper flue end along the outer periphery of the lower flue end is surrounded. In addition, if a through hole communicating with the lower flue is formed at the base end of the dust trapping piece, even if dust leaks from the clearance of the connecting portion, the dust trapping piece It can be stopped and trapped, and dust scattering around the exhaust flue can be suppressed, and the trapped dust can be immediately reduced into the lower flue through the through hole, which is suitable in terms of maintenance.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  Reference numeral 1 in the figure denotes a dryer for heating materials such as new aggregate and asphalt pavement waste, which are installed in the asphalt plant according to the present invention, to a desired temperature. A cylindrical drum 2 provided around the base 3 is tilted and supported rotatably by a support roller 4 disposed on a base 3, and is driven to rotate at a predetermined speed by a drive motor 5.

  One end of the drum 2 penetrates into a hot hopper 7 provided with a burner 6 for supplying hot air, while the other end penetrates into a cold hopper 9 provided with an exhaust flue 8 for exhaust gas discharge. In addition, the cold hopper 9 is provided with a belt conveyor 10 for supplying materials such as new aggregate and asphalt pavement waste material into the drum 2.

  The hot hopper 7 and the cold hopper 9 are mounted on the base 3 together with the drum 2, while the base 3 is substantially in the longitudinal direction of the bottom of the base (left and right direction in FIG. 1). The shaft support 11 is pivotally supported on the floor surface so as to be tiltable, and two hydraulic cylinders 12 as lifting means are arranged in pairs at opposing positions on both sides of the shaft support 11. Thus, the inclination angle of the drum 2 on the base 3 can be changed according to the raising / lowering operation of each hydraulic cylinder 12. In order to prevent the base 3 from vibrating due to the rotational drive of the drum 2, vibrations of the base 3 are suppressed by using ball joints at the upper and lower mounting portions of the hydraulic cylinder 12.

  The initial tilt angle and the movable angle range of the drum 2 may be appropriately set according to the state and characteristics of the material to be heat-treated, the type of the mixture to be manufactured, and the like. If the movable angle range is set to about 4 ° ± 2 °, which is adopted by various dryers, the optimum heating can be performed according to the state and characteristics of various materials and the type of mixture to be produced. It becomes possible to adjust to the amount.

  Further, as shown in FIG. 2, the exhaust flue 8 in the immediate vicinity of the cold hopper 9 exit is divided into a lower flue 8a and an upper flue 8b, and these lower flue 8a and upper flue 8b are suitable. In order to suppress wear due to dust in the exhaust gas while having a clearance, the lower flue 8a on the exhaust gas upstream side is loosely fitted in the upper flue 8b on the downstream side and connected, It is structured to be inclined substantially parallel to the tangential direction of the circle whose radius is the distance to the connecting portion with the shaft support portion 11 as the center, and as shown by the two-dot chain line in FIG. The clearance between the swinging lower flue 8a and the fixedly supported upper flue 8b is kept substantially constant so that the ends of the respective flues do not come into contact with each other to cause interference.

  Further, the periphery of the connecting portion between the lower flue 8a and the upper flue 8b is enclosed and sealed by a bellows 13 which is a cover body that can be bent and stretched, and the lower flue 8a accompanying the tilt of the base 3 is sealed. While allowing the rocking to be flexed or stretchable by the bellows 13, dust in the exhaust gas leaking from the clearance between the lower flue 8 a and the upper flue 8 b scatters and pollutes the surroundings, or the outside air causes the clearance. The intrusion into the exhaust flue 8 further prevents problems such as an increase in the load on the downstream dust collector (not shown).

  Reference numeral 14 in the figure denotes a bucket elevator that is a vertical conveying device that conveys the material heat-dried by the dryer 1 to the upper part of an adjacent plant body (not shown), and is an aggregate provided in the hot hopper 7. The leading end of the discharge chute 15 is connected to the aggregate receiving hopper 16 of the bucket elevator 14, and also at the connecting portion, as shown in FIG. In order to prevent this from happening, they are connected by loose fitting with an appropriate clearance.

  Further, the periphery of the connecting portion between the aggregate discharge chute 15 and the aggregate receiving hopper 16 is also surrounded and sealed by the bellows 17 in the same manner as described above, and the aggregate discharge chute 15 swings as the base 3 tilts. While allowing movement by the flexibility and stretchability of the bellows 17, it is intended to prevent dust leaking from the clearance between the tip of the aggregate discharge chute 15 and the aggregate receiving hopper 16 from scattering and contaminating the surroundings. Yes.

  And when adjusting the amount of heating according to the state and characteristics of the material to be heat-treated, for example, when increasing the amount of heating with respect to a material having a high moisture content or a property that makes it difficult for moisture to escape The hydraulic cylinders 12 provided at both ends of the base 3 are moved up and down to change the tilt angle of the drum 2 from, for example, a normal 4 ° to 2 °. Then, in the drum 2 with a gentle inclination angle, the material feed rate decreases, and the residence time of the material in the drum 2 becomes longer. As a result, the amount of heating increases and the moisture in the material is sufficiently reduced. Is possible. On the other hand, when the heating amount is decreased, each hydraulic cylinder 12 is moved up and down to change the tilt angle of the drum 2 from, for example, a normal 4 ° to 6 °. Then, in the drum 2 where the inclination angle becomes steep, the feed rate of the material increases, and the residence time of the material in the drum 2 is shortened. As a result, the amount of heating can be reduced.

  At this time, since the hot hopper 7 and the cold hopper 9 are mounted together with the drum 2 on the base 3 that is pivotably supported, the tilt angle of the drum 2 is changed as in the conventional device. The lower flue in which the exhaust flue 8 in the immediate vicinity of the cold hopper 9 is divided can be avoided as much as possible to avoid the occurrence of a problem that the sealing performance at the end of the drum 2 is impaired due to the change in the gap interval with each hopper. Since the connecting portion between 8a and the upper flue 8b and the connecting portion between the aggregate discharge chute 15 of the hot hopper 7 and the aggregate receiving hopper 16 of the bucket elevator 14 are provided with appropriate clearances, the drum 2 Even if the support angle of the cold hopper 9 or the hot hopper 7 changes with the change of the inclination angle, the devices do not come into contact with each other and interfere with each other, and the inclination angle of the drum 2 is increased. It is possible to concrete specific change unreasonable and without problems.

  In addition, the position of the shaft support portion 11 that supports the base 3 is installed on one end side of the base 3 as in the conventional device, for example, and a hydraulic cylinder 12 that is an elevating means is installed on the other end side of the base 3. However, as in this embodiment, the pivoting width of the hot hopper 7 or the cold hopper 9 when the base 3 is tilted can be reduced by pivotally supporting the base 3 at the substantially central portion in the longitudinal direction. This makes it easy to adjust the connection at each connecting portion with the peripheral device, and can support the base 3 in a balanced and stable manner, and employs a relatively small hydraulic cylinder 12. It becomes possible.

  FIG. 4 shows another embodiment of the connecting portion of the lower flue 8a and the upper flue 8b obtained by dividing the exhaust flue 8, and in the present embodiment, the upper flue 8b is provided in the upper flue 8b. Along the outer periphery of the loosely placed lower flue 8a, the exhaust gas flow surrounding the connecting portion with the opposing upper flue 8b and preventing leakage of exhaust gas from the clearance provided between each flue is prevented. A substantially annular dust trapping piece 18 that dams up the dust contained therein and effectively traps the dust is provided, and a plurality of pieces that communicate with the inside of the lower flue 8a are provided at the base end portion of the dust trapping piece 18. The dust D trapped by the dust trapping piece 18 is reduced into the lower flue 8a through the through-hole 19.

  In addition, it is preferable that the dust reduction through-holes 19 are formed in the vicinity of the base end portion of the dust trapping piece 18 in this way, so that maintenance can be saved. However, by forming the through-holes 19, the exhaust flue 8 If the turbulence of the exhaust gas flow occurs, for example, as shown in FIG. 5, a flue restricting portion 20 that reduces the inner diameter of the flue along the lower side of the through hole 19 is provided. Then, as shown by the arrow in FIG. 5, the flue gas flow in the flue can be controlled to drift to the flue center side, so that the turbulence of the flue gas flow due to the through-hole 19 can be suppressed and the flue gas can be transmitted from the flue. It is also possible to reduce the exhaust gas flow that tends to leak back to the dust capturing piece 18 side through the hole 19.

  Further, as shown in FIG. 6, if a substantially annular baffle plate 21 is provided so as to surround the dust trapping piece 18 facing from above, along the outer periphery of the upper flue 8b, each smoke The exhaust gas flow leaking from the clearance between the roads can be further prevented, and the dust D contained in the exhaust gas can be more effectively dammed and captured, which is more preferable in terms of maintenance.

  In addition, when changing the inclination angle of the drum 2 of the dryer 1 and adjusting the amount of heating to the material, the exhaust gas temperature is lowered and there is a concern about dew condensation in the flue. It is possible to control the exhaust gas temperature to some extent by controlling the driving motor 5 that rotationally drives the drum 2 using an inverter or the like and adjusting the rotational speed of the drum 2. For example, when the exhaust gas temperature has been lowered by gently adjusting the tilt angle of the drum 2, the material scraped up in the drum 2 can be adjusted by adjusting the rotation speed of the drum 2. By reducing the amount of gas and reducing the heating efficiency, the exhaust gas temperature can be raised and problems such as the occurrence of condensation in the flue can be prevented. Further, the exhaust flue 8 is provided with a temperature sensor for detecting the exhaust gas temperature, and the drive motor 5 is automatically controlled based on the exhaust gas temperature detected by the temperature sensor to adjust the rotational speed of the drum 2. You can also

  In this embodiment, the countercurrent dryer 1 in which the hot air direction from the burner 6 and the material flow direction oppose each other is used as the dryer, but conversely, the hot air direction from the burner 6 is used. Of course, it may be a parallel flow dryer 1 in which the material flow direction is the same.

DESCRIPTION OF SYMBOLS 1 ... Dryer 2 ... Drum 3 ... Base 6 ... Burner 7 ... Hot hopper 8 ... Exhaust flue 8a ... Lower flue 8b ... Upper flue 9 ... Cold hopper 11 ... Shaft support 12 ... Hydraulic cylinder (lifting means) 13, 17 ... Bellows (cover body)
14 ... Bucket elevator (aggregate vertical transfer device)
15 ... Aggregate discharge chute 16 ... Aggregate receiving hopper 18 ... Dust trapping piece 19 ... Through hole

Claims (4)

  A cylindrical drum having a large number of scraping blades inside is rotatably supported on a base, and one end of the drum is inserted into a hot hopper provided with a hot air supply burner, while the other end is In an asphalt plant dryer that penetrates into a cold hopper having an exhaust flue for exhaust gas derivation, the hot hopper and the cold hopper are mounted on a base together with the drum, and a predetermined length in the longitudinal direction of the base The position is pivotably supported on the floor surface, and a predetermined portion of the base is supported on the floor surface by lifting means, and the tilt angle of the drum on the base is adjusted according to the lifting operation of the lifting means. On the other hand, the exhaust flue immediately adjacent to the cold hopper exit is divided into a lower flue and an upper flue. The lower flue and the upper flue are separated from each other by the tilting of the base. Predetermined clear run to avoid contact The aggregate discharge chute of the hot hopper and the aggregate receiving hopper of the aggregate vertical conveying device have a predetermined clearance so that they do not come into contact with each other due to the tilt of the base. The asphalt plant dryer is characterized in that it is loosely fitted and connected, and each connecting portion is surrounded by a cover body that can be bent and stretched.   The connecting part between the lower flue and the upper flue is loosely fitted at a predetermined angle substantially parallel to the tangential direction of a circle whose radius is the distance to the connecting part with the pivot point of the base as the center. When the base is tilted, the lower flue of the connecting portion is swung substantially linearly with respect to the upper flue so that the clearance between the flues that are loosely fitted is maintained substantially constant. The asphalt plant dryer according to claim 1.   2. The base according to claim 1, wherein the base is pivotally supported at a substantially central portion in the longitudinal direction of the base, and a plurality of lifting means are arranged so as to be paired with opposing positions on both sides of the pivot support. The asphalt plant dryer according to claim 2 or 2.   The lower flue end is loosely fitted in the upper flue end, and the outer periphery of the lower flue end surrounds the connecting portion with the opposite upper flue end, and dams dust leaking from the clearance of the connecting portion. The dust trapping piece to be trapped is provided around and a through hole communicating with the inside of the lower flue is formed in the base end portion of the dust trapping piece so that the dust trapped by the dust trapping piece is below the through hole. 4. The asphalt plant dryer according to claim 1, wherein the asphalt plant dryer is configured to be reduced into a flue.

Images