JPH057482B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dryer for drying and heating asphalt aggregate, which is capable of drying and heating new aggregate and recycled aggregate under conditions suitable for them.

[Conventional technology]

Conventionally, in asphalt plants, when producing recycled composite material by mixing recycled aggregate with new aggregate,
In order to prevent the asphalt components contained in the recycled aggregate from deteriorating or burning, overheated new aggregate and room temperature recycled aggregate are mixed in a mixer, and the recycled aggregate is heated with the new aggregate. Alternatively, a dryer dedicated to recycled aggregate can be installed in the asphalt plant to heat the recycled aggregate, and this can be mixed with new aggregate heated in another dryer to produce recycled composite material. It has produced.

[Problem that the invention seeks to solve]

However, in the former case, there are restrictions on heating the new aggregate in terms of equipment or thermal efficiency, and it is not possible to heat the recycled aggregate according to theory, so the recycled aggregate tends to be insufficiently heated. There is some dissatisfaction with the fact that it is practically impossible to increase the percentage of recycled aggregate mixed in by more than 20%. Another drawback is that the asphalt properties contained in the recycled aggregate in the mixed recycled product are not restored, making it unfavorable in terms of quality.

In the latter case, although there is no disadvantage as mentioned above, in addition to the dryer for new aggregate, it is necessary to take the trouble to install a dedicated dryer for recycled aggregate, which increases the complexity of the equipment and increases the equipment cost. Of course, there is a problem in that the operating cost is high and it is economically inferior.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides an outer cylinder having a first exhaust manifold at one end, a second exhaust manifold at the middle, and an outer exhaust manifold at the other end; One end is equipped with a recycled aggregate discharge chute and a heating gas intake, and the other end is equipped with an inner cylinder exhaust manifold.
The exhaust chute is arranged in the second exhaust manifold part of the outer cylinder, and the inner cylinder exhaust manifold is arranged in the outer cylinder exhaust manifold part, and a gap is formed between the outer cylinder and the outer cylinder. an inner cylinder provided concentrically with the outer cylinder at the center; and an inner cylinder provided in the first discharge manifold of the outer cylinder so as to be movable relative to the heated gas intake port of the inner cylinder;
a burner whose distance from the intake port can be freely adjusted; a new aggregate feeding means provided at the other end of the outer cylinder for feeding new aggregate into the outer cylinder; and the other end of the inner cylinder. a recycled aggregate feeding means for feeding recycled aggregate into the inner cylinder; a dust collector connected to the outer cylinder exhaust manifold and the inner cylinder exhaust manifold via an exhaust duct; and the dust collector. The structure is equipped with an exhaust fan attached to the exhaust fan.

[Effect]

While rotating the outer cylinder and the inner cylinder in the circumferential direction and operating the burner to send heated gas into the outer cylinder, the heated gas is sucked by an exhaust fan,
New aggregate is introduced into the outer cylinder by the new aggregate injection means, and recycled aggregate is introduced into the inner cylinder by the recycled aggregate injection means. The new aggregate put into the outer cylinder as described above passes between the outer cylinder and the inner cylinder, gradually moves to one end side, is dried and heated by the heated gas, and is discharged from the first discharge manifold. The recycled aggregate introduced into the inner cylinder is heated and dried by heated gas fed into the inner cylinder from the intake port at one end, and is discharged from the second discharge manifold.

The heated gas that has worked to dry and heat the new aggregate and recycled aggregate in the outer cylinder and inner cylinder is sucked by the exhaust fan through the exhaust duct and is discharged to the atmosphere through the dust collector. When reducing the amount of heat of the heated gas passing through the inner cylinder and increasing the amount of heat of the heated gas passing through the space between the outer cylinder and the inner cylinder, increase the distance between the heated gas intake of the inner cylinder and the burner. In order to increase the distance, or conversely, to increase the amount of heat of the heated gas passing through the inner cylinder and reduce the amount of heat of the heated gas passing between the outer cylinder and the recycled aggregate, it is necessary to Reduce the distance between the

〔Example〕

1 and 2 show an embodiment of a dryer for drying and heating asphalt aggregate according to the present invention, and in these figures, reference numeral 1 denotes an inclined outer cylinder having a circular cross-sectional shape. As usual, this inclined outer cylinder 1 is placed in an inclined state on a support roller 2 on a base (none of which is shown) that is supported by a pivot and a jack and is provided so as to be tiltable up and down using the pivot as a fulcrum. It is configured to be placed on the shaft and rotated in the circumferential direction by a rotary drive device 3. Inclined outer cylinder 1
At the lower end (one end), middle part, and upper end (other end) of the
are individually provided and fixed to the base.

A cylindrical chamber 8 attached to the lower discharge manifold 4 is provided with a burner 9 equipped with a blower 7 so as to be movable in the front and back direction (left and right in FIG. 1), and the upper end of the inclined outer cylinder 1 At the center of the side, an inner cylinder 10 is provided concentrically with the inclined outer cylinder 1 with a gap 11 formed therebetween. This inner cylinder 10 is for drying and heating the recycled aggregate, and has a recycled aggregate discharge chute 12 and a heating gas intake port 13 at the lower end, and an inner cylinder exhaust manifold 14 at the upper end. The exhaust chute 12 is arranged at the upper exhaust manifold 5 part of the inclined outer cylinder 1, and the inner cylinder exhaust manifold 14 is arranged at the outer cylinder exhaust manifold 6 part, and the exhaust chute 12 and the rod-shaped support 15 are arranged to tilt the exhaust chute 12 and the rod-shaped support 15. It is fixed to the outer cylinder 1.

Further, at the upper end of the inclined outer cylinder 1, a new aggregate charging means 16 such as a belt conveyor for charging new aggregate into the inclined outer cylinder 1 is provided, and at the upper end of the inner cylinder 10, an inner Recycled aggregate charging means 17 such as a hopper for charging recycled aggregate into the cylinder 10 is provided through the inner cylinder exhaust manifold 14, while the upper exhaust manifold 5 and the outer cylinder exhaust manifold 6
A communication duct 19 equipped with a damper 18 is provided between the upper exhaust manifold 5 and the outer cylinder exhaust manifold 6.

The outer cylinder exhaust manifold 6 and the inner cylinder exhaust manifold 14 are provided with exhaust ducts 22 and 23 each equipped with dampers 20 and 21, and each exhaust duct 22 and 23 is equipped with an exhaust fan 24 and a damper 25. The dust collector 26 is connected to the duct 27 of the dust collector 26. A differential pressure switch 28 provided in the lower discharge manifold 4 is electrically connected to the damper 25, and when the pressure inside the inclined outer cylinder 1 becomes too low, the damper 25 moves in the closing direction and vice versa. When the internal pressure inside the inclined outer cylinder 1 becomes too high, the damper 2
5 moves in the opening direction to maintain the pressure inside the outer cylinder 1 within a predetermined range.

Furthermore, the blower 7 and the burner 9 are attached to a truck 29, and a moving device 30 such as a cylinder
The space 11 between the outer cylinder 1 and the inner cylinder 10 is changed by moving the chamber 8 in the left-right direction in FIG. The ratio of the amount of heat of the heated gas passing through the inner tube 10 to the amount of heat of the heated gas entering the inner cylinder 10 from the intake port 3 can be adjusted. A control panel 34 is connected to the moving device 30, and the control panel 34 has detection ends facing the lower inner sides of the lower and upper discharge manifolds 4 and 5 and the intake port 13 of the inner cylinder 10, respectively. A new aggregate thermometer 31 such as a thermocouple provided, and a recycled aggregate thermometer 3
2 and an intake thermometer 33 are electrically connected. For example, when the recycled aggregate thermometer 32 and the intake thermometer 33 detect a temperature lower than a predetermined temperature, the burner 9 From the state shown by the solid line in FIG. 1, move forward as shown by the two-dot chain line, approach the heated gas intake port 13 of the inner cylinder 10, and feed the center portion of the high-temperature flame directly into the intake port 13 for heating as it passes through the inside of the inner cylinder 10. When the calorific value of the gas is increased, or conversely when the recycled aggregate thermometer 32 and the intake thermometer 33 detect a temperature higher than the predetermined temperature, the burner 9 changes from the two-dot chain line state to the solid line state. It is configured to reduce the amount of heat of the heated gas that is retreated and sent into the inner cylinder 10.

Reference numeral 35 is a chimney, and 36 and 37 are well-known scraping blades provided on the inner peripheral surfaces of the inclined outer cylinder 1 and the inner cylinder 10.

Although not shown, the inclined outer cylinder 1 and the lower exhaust manifold 4, the inclined outer cylinder 1 and the upper exhaust manifold 5, the inclined outer cylinder 1 and the outer exhaust manifold 6, and the inner cylinder 10 and the inner cylinder exhaust manifold 14. The contact portion has an air seal structure such as a labyrinth. The dryer usually includes a hot elevator that receives the new aggregate discharged from the lower discharge manifold 4 via a feeder, a screen that sieves the new aggregate received from the hot elevator according to particle size, and a screen that sieves the new aggregate by particle size. A hot bin for storing the new aggregate according to particle size, a weighing hopper installed under the hot bin, a mixer installed under the weighing hopper, and regenerated bone discharged from the discharge feeder of the upper discharge manifold. A well-known batch tower (not shown) is connected thereto, comprising a surge bin for receiving and storing recycled aggregate material via a conveyor and depositing the recycled aggregate into the weighing hopper as required.

Next, the operation of the dryer for drying and heating asphalt aggregate according to the present invention configured as described above will be explained.

New aggregate feeding means rotates the inclined outer cylinder 1 and the inner cylinder 10 in the circumferential direction, operates the exhaust fan 24, and feeds heated gas into the inclined outer cylinder 1 by operating the burner 9. At step 16, recycled aggregate is charged into the inclined outer cylinder 1, and recycled aggregate is charged into the inner cylinder 10 by means of recycled aggregate charging means 17.

The new aggregate placed in the inclined outer cylinder 1 moves to the lower end of the inclined outer cylinder 1 through the gap 11 between the inclined outer cylinder 1 and the inner cylinder 10, and is discharged from the lower discharge manifold 4. However, during this time, the inside of the inclined outer cylinder 1 is dry-heated in a countercurrent manner by the heating gas moving from right to left in FIG. Furthermore, the recycled aggregate placed in the inner cylinder 10 gradually moves to the right in the inner cylinder 10 as seen in FIG. and is discharged from the discharge chute 12 to the upper discharge manifold 5. The new aggregate discharged from the lower discharge manifold 4 and the recycled aggregate discharged from the upper discharge manifold 5 are finally mixed in the mixer of the batch tower to form a recycled composite material.

The heated gas that works to dry and heat the new aggregate and recycled aggregate and reaches the outer cylinder exhaust manifold 6 and the inner cylinder exhaust manifold 14 enters the dust collector 26 through the exhaust ducts 22 and 23 to remove dust and the like. After being cleaned, it is released into the atmosphere from the chimney 35. In addition to the above, the heated gas leaked into the upper exhaust manifold 5 through the exhaust chute 12 enters the outer cylinder exhaust manifold 6 through the communication duct 19, and is purified through the dust collector 26 in the same manner as described above. released into the atmosphere. Therefore, the flow of heated gas sent into the outer cylinder 1 by the blower 7 is
0, no blowback phenomenon occurs at the upper discharge manifold 5.

In the above, the amount of heated gas sucked and exhausted from the upper discharge manifold 5 is controlled by adjusting the opening degree of the damper 18. If the heating temperature of the new aggregate is lower than a predetermined temperature, either increase the opening of the damper 20, reduce the opening of another damper 21, or increase the opening of the damper 20 and , the opening degree of the other damper 21 is lowered to increase the amount of heated gas passing through the gap 11 between the outer cylinder 1 and the inner cylinder 10. If the temperature of the recycled aggregate is lower than the expected temperature, increase the opening of the damper 21 or use another damper 2.
The opening degree of the damper 21 is decreased or the opening degree of the damper 21 is increased, and the opening degrees of the other dampers 20 are decreased to increase the amount of heated gas passing through the inner cylinder 10. If the temperature of new aggregate is high or the temperature of recycled aggregate is high, the damper 2
Needless to say, 0 and 21 are opened and closed. If for some reason the overall opening degree of the dampers 20 and 21 becomes too large and the pressure inside the outer cylinder 1 becomes low, the damper 25 is moved in the closing direction by the signal from the differential pressure switch 28. When the damper 25 rotates and the pressure inside the outer cylinder 1 is high, the damper 25 rotates in the opening direction in response to a signal from the differential pressure switch 28.

Apart from the above, by moving the burner 9 back and forth with the moving device 30, the ratio of the amount of heat of the heated gas passing through the gap 11 and the inner cylinder 10 can also be adjusted. That is, when the burner 9 is advanced from the state shown by the solid line to the state shown by the two-dot chain line in FIG. Even if the flow rate of the heating gas is the same, the amount of heat increases, and the amount of heat of the heating gas passing through the gap 11 decreases. When burner 9 is moved back from the state shown by the two-dot chain line to the state shown by the solid line,
Conversely, the amount of heat of the heated gas passing through the inner cylinder 10 decreases, and the amount of heat of the heated gas passing through the gap 11 increases.

Temperature control for new aggregate and recycled aggregate is basically as described above, but if, for example, the temperature of both new aggregate and recycled aggregate is too high or too low, adjust the burner 9. or adjust the input amount of new aggregate and recycled aggregate.

Normally, a computer control panel 34 is also connected to each damper 20, 21, and each damper 20, 21 is adjusted based on the set temperatures of new aggregate and recycled aggregate, their actual heating temperature, the temperature of heating gas, etc. Burner 9
The computer controls the forward and backward movement of the machine. When controlling the movement of the burner 9, the opening degree of each damper 20, 21, etc. using a computer, the maximum heating temperature of the recycled aggregate and the mixture temperature are set to prevent the asphalt components of the recycled aggregate from burning or deteriorating. To produce a composite material at a predetermined temperature without any heat loss. The mode of automatic control of each damper 20, 21 by a computer is generally proportional control, but is not limited to this. The opening/closing control of the other dampers 18 can also be controlled by the computer. Dust collector 2
6. Dry dust collectors such as bag filters,
A wet type dust collector such as a water scrubber, or one in which both a dry type and a wet type are installed side by side, is used, but the specific structure is arbitrary.

Other embodiments and technical matters other than those described above are listed below.

(1) The outer cylinder exhaust manifold 6 and the inner cylinder exhaust manifold 14 may be the same.

(2) The chamber 8 may also be configured to move together with the burner 9.

(3) The dust collector 26 can also be directly connected to the upper discharge manifold 5.

(4) The burner 9 can also be moved manually.

(5) It is also possible to make the entire inner cylinder 10 or a portion of the intake port 13 movable so that the distance L between the intake port 13 and the burner 9 can be freely adjusted.

〔Effect of the invention〕

As explained above, the dryer for drying and heating asphalt and aggregate according to the present invention has a first
An outer cylinder having a discharge manifold, a second discharge manifold in the middle part, an outer cylinder exhaust manifold in the other end, a recycled aggregate discharge chute and a heating gas intake in one end, and the other end. The exhaust chute is provided in the second exhaust manifold part of the outer cylinder, and the inner cylinder exhaust manifold is provided in the outer cylinder exhaust manifold part. an inner cylinder provided concentrically with the outer cylinder at the center of the outer cylinder with a gap formed between the inner cylinder and the first discharge manifold of the outer cylinder relative to the heated gas intake port of the inner cylinder; a burner that is movably provided and whose distance from the intake port can be adjusted; a new aggregate feeding means that is provided at the other end of the outer cylinder and that feeds new aggregate into the outer cylinder; A recycled aggregate feeding means provided at the other end of the inner cylinder for feeding recycled aggregate into the inner cylinder, and a dust collector connected to the outer cylinder exhaust manifold and the inner cylinder exhaust manifold via an exhaust duct. and an exhaust fan attached to the dust collector, the recycled aggregate can be efficiently dried and heated without degrading or burning the asphalt components. be able to. In addition, it is easy to increase the mixing ratio of recycled aggregate to new aggregate, and there is no need for a dedicated dryer for recycled aggregate, so two dryers can be installed to mix new aggregate and recycled aggregate. Compared to producing a composite material by drying and heating, it requires less equipment and operating costs, making it more economical. Furthermore, since the distance between the intake port and the burner can be adjusted freely, the moisture content of new aggregate and recycled aggregate changes significantly, making it difficult to accurately control the temperature by simply adjusting the damper opening. Even in such a case, the temperature can be adjusted accurately by changing the distance between the intake port and the burner.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment of a dryer for drying and heating asphalt aggregate according to the present invention, and FIG. 2 is a sectional view of the portion shown in FIG. 1. 1... Outer cylinder, 4... First discharge manifold, 5
...Second exhaust manifold, 6...Outer cylinder exhaust manifold, 9...Burner, 10...Inner cylinder, 11...
...= between, 12... discharge chute, 13... intake, 14... inner cylinder exhaust manifold, 16... new aggregate charging means, 17... recycled aggregate charging means,
22...Exhaust duct, 23...Exhaust duct, 24
...Exhaust fan, 26...Dust collector, L...Separation distance.

Claims (1)

[Claims] 1 An outer cylinder with a first discharge manifold at one end, a second discharge manifold at the middle, and an outer cylinder exhaust manifold at the other end, and a recycled aggregate discharge chute and heating gas intake at one end. and an inner cylinder exhaust manifold at the other end, the exhaust chute is arranged in a second exhaust manifold part of the outer cylinder, and the inner cylinder exhaust manifold is arranged in a part of the outer cylinder exhaust manifold, respectively. and an inner cylinder provided concentrically with the outer cylinder at the center of the outer cylinder with a gap formed between the inner cylinder and the outer cylinder, and the heated gas intake port of the inner cylinder connected to the first discharge manifold of the outer cylinder. a burner that is movable relative to the intake port and whose distance from the intake port can be adjusted; and a new bone that is provided at the other end of the outer cylinder and that feeds new aggregate into the outer cylinder. a material input means;
A recycled aggregate feeding means provided at the other end of the inner cylinder for feeding recycled aggregate into the inner cylinder, and a dust collector connected to the outer cylinder exhaust manifold and the inner cylinder exhaust manifold via an exhaust duct. 1. A dryer for drying and heating asphalt aggregate, comprising: and an exhaust fan attached to the dust collector.