JP3001506B2 - Asphalt recycling plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an asphalt recycling plant for heating and regenerating asphalt waste material (hereinafter, referred to as "waste material") generated by repairing and repairing an existing asphalt pavement road.

[0002]

2. Description of the Related Art Asphalt-paved roads are susceptible to cracks and ruts due to long-term use. Therefore, as a repair method, asphalt-paved roads are used to overlay asphalt on existing pavement. A so-called replacing method is used to excavate the whole. Waste materials excavated by such refilling and road construction work can be mixed with new asphalt materials and re-used as a pavement material in view of the recent regulations on industrial waste disposal and effective use of resources. Used as

[0003] Such a method of recycling waste materials can be roughly divided into a normal temperature charging method in which normal temperature waste materials are charged into heated asphalt new material, Japanese Utility Model Publication No. Sho 62-18263, Japanese Utility Model Publication No. Sho 62-32282, and the like. 62-17709
As disclosed in No. 5 Publication, etc.,
There is a heating charging method in which the mixing ratio is increased by heating to a degree, thereby increasing the charging ratio of waste materials to new asphalt materials.

However, when the waste material is heated to 150 ° C. or more, the effective asphalt component in the waste material is deteriorated, and so-called blue smoke is generated due to overburning.
In order to prevent this, the present applicant disclosed in Japanese Patent Application Laid-Open No. 6-41558.
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-115, a half-dry method is also used in which waste materials are heated to 60 to 100 ° C. to evaporate water in the waste materials and then mixed.

FIG. 4 is a schematic diagram of a conventional asphalt recycling plant used in a heating charging system and a half-dry system. In the figure, an asphalt recycling plant includes a dryer 21 for heating asphalt waste material,
A storage bin 22 which is disposed on an elevated stand and temporarily stores the heated waste material, a transport device 23 which transports the heated waste material from a waste material discharge part of the dryer 21 to the storage bin 22, a measuring device 24 for the heated waste material, and a new asphalt heating waste material. Mixing device 25 for asphalt plant for mixing with materials, measuring device 24 for heating waste materials
And a simple transfer device 26 such as a conveyor that transfers the waste material from the waste material discharge section to the mixing device 25.

In such a configuration, waste materials generated by repairing and repairing existing asphalt pavement roads are supplied to a dryer 21 and heated, and the heated waste materials are transported to a storage bin 22 provided on an elevated stand. It is transported by the device 23 and temporarily stored. When the asphalt mixture is mixed and manufactured by the mixing device 25, the heated waste material stored in the storage bin 22 is appropriately taken out, and a predetermined amount is measured by the measuring device 24. The asphalt new material is conveyed by a conveying device 26 to the asphalt new material at a predetermined ratio.

[0007] However, in the method in which the heated waste material heated by the dryer 21 is lifted by the transfer device 23 to the storage bin 22 provided on the elevated platform, the devices of the asphalt recycling plant are scattered on the premises. There is a problem that a large space is required, and that a transport device 23 that transports the heated waste material to the storage bin 22 installed on the elevated stand is large-scale, and the operation power is large, and the maintenance is troublesome.

[0008] Therefore, there is an asphalt recycling plant disclosed in Japanese Utility Model Laid-Open No. 6-63606 which has solved these problems. FIG. 5 is a schematic view of a conventional asphalt recycling plant described in this publication, and has a configuration in which the transfer device 23 of the asphalt recycling plant described in FIG. 4 is eliminated and the dryer 21 is provided on an elevated stand. ing. Thereby, it becomes possible to drop the heated waste material heated by the dryer 21 into the storage bin 22 and the weighing device 24 by natural fall and carry it. Then, it is transported to the mixing device 25 by the transport device 26 and mixed with a new asphalt material at a predetermined ratio.

[0009]

However, even in such an asphalt recycling plant, the heated waste material heated by the dryer 21 is hardened in the storage bin 22 when the storage time in the storage bin 22 is prolonged. To prevent this and prevent the temperature from lowering, the storage bin 22 is provided with a heating device, a heat insulating material, and the like.
There was a disadvantage that the power of the heating device, the heat insulating material, and the like were expensive.

Accordingly, an object of the present invention is to provide an asphalt recycling plant which eliminates problems caused by the existence of the conventional storage bins, and realizes space saving, energy saving and maintenance of equipment.

[0011]

In order to achieve the above object, an asphalt recycling plant according to the present invention conveys heated waste material to a mixing device via a supply chute below a waste material discharge section of a dryer for heating asphalt waste material. The supply chute is provided with a detection device for detecting the retention of the heated waste material, and a control device for controlling the operation of the dryer based on the detection result by the detection device is provided.

With such a configuration, the operation of the dryer is controlled based on the staying state of the heated waste material in the supply chute, that is, wasteful heat radiation is performed by sequentially supplying the required minimum amount of the heated waste material to the supply chute. Thus, the waste heating material can be efficiently transported to the mixing device. Further, by using the dryer itself as a storage device for the heated waste material, the storage bin can be eliminated, and the heated waste material is hardly cooled, so that the cooled heated waste material does not adhere to the wall surface of each device.

If the angle of the wall surface of the supply chute is set to a substantially right angle so that the material can easily flow in the conveying direction of the conveying device, the heated waste material can be efficiently conveyed without adhering to the wall surface. In addition to a normal belt conveyor, a closed-type screw feeder with heating and heat retention, a charging chute, and the like are used for the transport device.

Further, the control device may have a function of controlling supply of waste material to the dryer, combustion of a burner, and rotation of a drum in the dryer. As a result, it becomes possible to supply the necessary heating waste material with the minimum necessary power, and it is possible to efficiently supply the heating waste material to the mixing device.

Further, in addition to the above configuration, the asphalt recycling plant of the present invention may be provided with a heating waste material measuring device between the transport device and the mixing device.
With such a configuration, the heating waste material can be measured by the measuring device, and the conveying device can be operated in accordance with the measurement to supply a predetermined amount of the heating waste material from the conveying device to the mixing device.

Alternatively, the transfer device may be provided with a function of measuring a transfer amount of the heated waste material. Accordingly, a predetermined amount of the heated waste material can be measured by the transfer device without providing a separate measuring device, and the equipment can be downsized.

[0017]

[First Embodiment] FIG. 1 is a schematic diagram of an asphalt recycling plant according to a first embodiment, and FIG. 2 is a flowchart of processing by the control device of FIG.

As shown in FIG. 1, the asphalt recycling plant according to the first embodiment transports heated waste material to a mixing device 10 via a supply chute 7 below a waste material discharge portion of a dryer 5 for heating the waste material. 8 and
Heating waste material measuring device 9 between conveying device 8 and mixing device 10
Is provided. The dryer 5 has a burner 4 for feeding hot air. The angle of the wall surface of the supply chute 7 is such that the material easily flows in the transport direction of the transport device 10,
The shape is close to a right angle so that the heating waste does not adhere. Further, the supply chute 7 is provided with a retention sensor 6 as a detecting device for detecting retention of the heated waste material at a position for detecting when the heated waste material has accumulated to a certain level.

Further, on the burner 4 side of the dryer 5, a waste material cutting device 1 and conveying devices 2 and 3 for finely cutting a large lump of waste material excavated are arranged, and the waste material is lifted from the ground and supplied into the dryer 5. It is supposed to.
Here, the waste material cutting device 1, the transport devices 2, 3, the burner 4, and the dryer 5 are controlled by a control panel 11 as a control device based on the detection result of the stagnation sensor 6.

In such a configuration, waste material excavated by refilling or road construction is finely cut by the waste material cutting device 1 and supplied into the dryer 5 by the transport devices 2 and 3. The dryer 5 rotatably supports a cylindrical drum inclined toward the outlet side and rotates the drum at a predetermined speed. The dryer 5 rolls the supplied waste material while scraping it by a number of scraping blades disposed inside the drum. While moving down, it is heated to a predetermined temperature by contacting with hot air sent from the burner 4, and is supplied to the measuring device 9 by the transfer device 8 via the supply chute 7. The heated waste material is measured in a predetermined amount by the measuring device 9 and is charged into the mixing device 10.

Next, the state of control by the control panel 11 will be described with reference to FIG. First, the burner 4 is ignited, the drum in the dryer 5 is rotated, the waste material cutting device 1 and the transport devices 2 and 3 are operated, and the supply of the waste material into the dryer 5 is started. Further, the transport device 8 and the weighing device 9 are stopped. The heated waste material heated by the dryer 5 is discharged to the supply chute 7. At this time, since the transport device 8 is stopped, the heated waste material stays in the supply chute 7 and when the waste material reaches a certain level, the stay sensor 6 detects the stay. When the stay is detected, the burner 4 is extinguished, the rotation of the drum in the dryer 5 is stopped, and the discharge of the heated waste material to the supply chute 7 is completed. At this time, the waste heating material remaining in the dryer 5 is stored in the dryer 5 as it is. That is, the dryer 5 serves as a storage bin.

Next, the supply of the heated waste material to the mixing device 10 is started by operating the measuring device 9 and the conveying device 8. When the supply of the heated waste material progresses and the heated waste material in the supply chute 7 decreases to a certain level, the retention sensor 6 does not detect the heated waste material. At the same time, the burner 4 is ignited again, the drum in the dryer 5 is rotated, and the waste material cutting device 1 and the transport devices 2 and 3 are operated to start supplying the waste material into the dryer 5. At this time, the heated waste material remaining in the dryer 5 is again heated by the dryer 5 and discharged to the supply chute 7.

On the other hand, the heated waste material conveyed by the conveying device 8 is measured in a predetermined amount by the measuring device 9 and discharged to the mixing device 10. If the transfer device 8 is continuously operated, the supply chute 7
The level of the heated waste material remaining in the inside is reduced, and the waste material is supplied as described above. When the operation of the transport device 8 is stopped, the heated waste material stays in the supply chute 7 and is detected by the stay sensor 6, and the waste material supply is stopped. That is, the heating waste material is automatically supplied by the operation of the transport device 8.

When the operation of the transfer device 8 is stopped,
Although the waste heat material remains on the transfer device 8, in the case of the above-mentioned half-dry method, since the original temperature is as low as 60 to 100 ° C., the amount of heat dissipated per hour is small, and the waste heat material remains on the transfer device There is no problem in driving. Further, if the heating waste material remains on the transfer device temporarily, the moisture can be evaporated. On the other hand, in the case of the heating charging method of heating to about 150 ° C., a screw feeder with a closed-type heating and keeping heat is generally used for the transfer device, so that there is no operational problem.

[Embodiment 2] FIG. 3 is a schematic view of an asphalt recycling plant according to a second embodiment.
In the figure, a conveying device 8 is composed of a plurality of rollers and a wide endless annular belt 14.
Is a steel cylinder in which a strain gauge for converting strain into electrical resistance is adhered around a steel cylinder. At the end of the cylinder, the shaft of one of the rollers 12 constituting the transfer device 8 is attached. , The load applied to the roller 12 is detected. The rest of the configuration is the same as that of the first embodiment, and thus the description thereof is omitted, but the weighing device 9 in the first embodiment is omitted.

In such a configuration, the transport device 8 is operated by rotating the roller 12 at a constant speed. At this time,
The rotation speed of the roller 12 is measured, and the speed of the belt 14 is calculated. At the same time, the load caused by the heated waste material applied to the roller 12 is detected by the load cell 13. By integrating the weight of the heated waste conveyed for a certain period of time based on the speed of the belt 14 and the load of the load cell 13, the amount of the heated waste conveyed can be measured.

As described above, the transfer device 8 is provided with the function of measuring the transfer amount of the heated waste material.
Without the provision of the measuring device, a predetermined amount of the heated waste material can be measured by the transport device 8, so that the measuring device 9 can be eliminated and the equipment can be downsized.

[0028]

According to the present invention, the following effects can be obtained.

(1) A transport device for transporting the heated waste material to the mixing device via a supply chute is provided below the waste material discharge section of the dryer for heating the asphalt waste material, and a detection device for detecting the retention of the heated waste material in the supply chute is provided. By providing a control device for controlling the operation of the dryer based on the detection result by the detection device, it is possible to efficiently transport the heated waste material to the mixing device. In addition, by using the dryer itself as the storage device for the heated waste material, the storage bin can be eliminated and unnecessary heat radiation can be eliminated. That is, space saving, energy saving and maintenance saving of the equipment can be realized.

(2) The control device is provided with a function of controlling the supply of waste materials to the dryer, the combustion of the burner, and the rotation of the drum in the dryer, so that the required amount of heated waste materials can be reduced with a minimum power. And the heating waste material can be efficiently supplied to the mixing device.

(3) By providing a measuring device for the heated waste material between the conveying device and the mixing device, a predetermined amount of the heated waste material is supplied from the conveying device to the mixing device and mixed with the new asphalt material to mix the asphalt mixture. Can be manufactured, and high-quality asphalt can be manufactured.

(4) Since the transfer device is provided with a function of measuring the transfer amount of the heated waste material, the measurement device can be eliminated, and the space of the equipment can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an asphalt recycling plant according to a first embodiment.

FIG. 2 is a flowchart of a process performed by the control device of FIG. 1;

FIG. 3 is a schematic diagram of an asphalt recycling plant according to a second embodiment.

FIG. 4 is a schematic view of a conventional asphalt recycling plant.

FIG. 5 is a schematic view of a conventional asphalt recycling plant.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Waste material cut-out device 2, 3, 8 Transport device 4 Burner 5 Dryer 6 Staying sensor 7 Supply chute 9 Metering device 10 Mixing device 11 Control panel 12 Roller 13 Load cell 14 Belt

Claims (4)

(57) [Claims] In an asphalt recycling plant that heats asphalt waste material and mixes it with new asphalt material to produce an asphalt mixture, the heating waste material is supplied through a supply chute below a waste material discharge section of a dryer that heats the asphalt waste material. A transport device for transporting to the mixing device is provided,
An asphalt recycling plant provided with a detection device for detecting retention of heated waste material in the supply chute, and a control device for controlling operation of the dryer based on a detection result by the detection device. 2. The asphalt recycling plant according to claim 1, wherein the control device has a function of controlling supply of waste material to the dryer, combustion of a burner, and rotation of a drum in the dryer. Wherein the conveying device and asphalt recycling plant of claim 1 or 2 wherein is provided a metering device for heating waste material during the mixing device. Wherein said conveying device to the asphalt recycling plant of claim 1, wherein having a function of measuring a conveyance amount of heating waste.