JPH0363303A - Device for recycling scrapped asphalt pavement material - Google Patents

Abstract

PURPOSE:To achieve environmental preservation with pollution by offensive smell prevented by reheating the whole quantity of exhaust gas emitted from a drum that heats scrapped asphalt and returned to a combustion chamber, and by making the same odorless with odorful ingredients or the like decomposed. CONSTITUTION:Scrapped asphalt is supplied with a belt conveyor 16 to the inside of a drum 3 and is heated therein up to a required temperature. Exhaust gas generated in the drum 3 is then drawn and exhausted with an exhauster 10 and is returned to a combustion chamber 7 being freed of dust with a dust collector 11. Then the exhaust gas is heated with a burner 6 and is made odorless thereby, and is recyled for heating the scrapped material after being supplied again into the drum 3. Surplus gas accumulated during the process is then discharged through a diacharging flue 14 to the outside by plus pressure of a hot hopper 5. Thereby the whole quantity of the exhaust gas can be reheated and made odorless with odorful ingredients decomposed, and environmental pollution by offensive smell can be prevented too.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an apparatus for recycling asphalt pavement waste generated during replacement and repair of existing asphalt pavement, and furthermore, construction of equipment buried under the existing asphalt pavement. It is related to.

[Prior Art] Asphalt pavement waste material (hereinafter referred to as "waste material") dug up during road construction, etc. has come to be heated and regenerated using a dryer, which is a heating device, and to be effectively recycled.

[Problem to be solved by the invention] However, when waste materials containing asphalt are heated, a bad odor is generated, and this bad odor may be radiated into the neighborhood. Therefore, from the perspective of environmental conservation, countermeasures against the bad odor are necessary. It has become to.

Therefore, in view of the above points, the present invention aims to propose an asphalt pavement waste recycling device that can deodorize at low cost without using a large-sized deodorizing device.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a burner equipped with a combustion chamber on the hot hopper side of one end of the drum for heating and regenerating asphalt pavement waste, while An exhaust fan is interposed in the middle of the circulation flue connected to the cold hopper at the end, and the end of the circulation flue is connected to the combustion chamber,
The present invention provides an apparatus for recycling asphalt pavement waste material, characterized in that the hot hopper is provided with a discharge flue for discharging part of the gas in the drum to the outside.

[Function] In the asphalt pavement waste recycling device according to the present invention, the entire amount of exhaust gas led out from the cold hopper side of the drum is returned to the combustion chamber disposed on the hot hopper side, and the exhaust gas is combusted in the combustion chamber. It decomposes into carbon dioxide gas and water vapor, making it odorless. The high-temperature exhaust gas reheated in the combustion chamber is sent into the drum again to heat the waste material inside the drum.

At this time, out of the total amount of gas in the drum, the amount of gas that gradually increases due to the combustion air taken in from the burner, the air that enters through the drum gap, and the steam generated from the heated waste materials is released from the exhaust flue installed in the hot hopper. It is being released.

[Example] Embodiments of the present invention will be described below based on the drawings.

1 is a dryer for heating and regenerating waste materials, and a cylindrical drum 3 with a large number of scraping blades 2 arranged around it is mounted on a machine base 4.
It is rotatably tilted upwardly and rotated at a predetermined speed by a drive device (not shown). 5 is a hot hopper disposed at one end of the drum 3, a burner 6 is disposed on the side of the hot hopper 5, and a combustion chamber 7 for forming a flame is provided in front of the burner 6. . Reference numeral 8 denotes a cold hopper disposed at the other end of the drum 3. A circulation flue 9 is connected to the cold hopper 8 for discharging the exhaust gas from the drum 3. An exhaust fan 10 that sucks and exhausts the exhaust gas led out from the drum 3 and a dust collector 1) that collects scattered dust in the exhaust gas are provided. The other end of the circulation flue 9 is connected to the combustion chamber 7, and the exhaust gas discharged from the drum 3 is guided to the combustion chamber 7. 1
Reference numeral 2 denotes an air volume adjustment damper disposed in the circulation flue 9 on the suction side of the exhaust fan 1O, and the air volume adjustment damper 12 has a temperature sensor 13 inserted into the combustion chamber 7 at an appropriate position to detect the temperature of the combustion chamber 7. The combustion chamber 7 is operated in response to the temperature within the combustion chamber 7.
The amount of suction of exhaust gas is controlled so that the temperature inside is approximately 800°C.

14 is a discharge flue connected to the hot hopper 5, and the discharge flue 14 collects combustion air taken in by the burner 6, air entering from each seal part of the dryer 1, and the drum 3.
Excess gas that gradually increases due to water vapor generated from heated waste materials inside the drum is released to the outside of the drum 3, and the excess gas is released to the outside by natural ventilation due to positive pressure inside the drum. Note that an exhaust fan may be provided in the discharge flue to forcefully exhaust the air.

The gas discharged from the discharge flue 14 has a high temperature, and in order to effectively utilize this high temperature gas, a heat exchanger 15 is disposed between the discharge flue 14 and the circulation flue 9. The temperature of the gas on the circulation flue 9 side is raised by the high temperature gas on the 14 side, and then the gas is sent into the combustion chamber 7 to recover heat.

When the waste material is heated and regenerated by the dryer 1, the waste material is supplied into the drum 3 by the belt conveyor 16, and the waste material is heated to a desired temperature while flowing down the drum 3. At this time, the exhaust gas accompanied by odor, blue smoke, and dust generated in the drum 3 is removed by the exhaust fan 10.
is suctioned and exhausted, dust is removed by a dust collector 1) provided in the middle of the circulation flue 9, and returned to the combustion chamber 7.

The exhaust gas returned to the combustion chamber 7 is heated to a high temperature by the flame of the burner 6, and the odor components and blue smoke in the exhaust gas are thermally decomposed and become odorless. The deodorized high-temperature exhaust gas is sent into the drum 3 again and reused to heat the waste material. Through exhaust gas circulation, the amount of gas corresponding to the amount of air required for combustion in the burner 6, the amount of air entering from each seal part of the drum 3, and the amount of water vapor generated as the waste material is heated becomes surplus gas and gradually increases. However, these surplus gases are discharged to the outside from the discharge flue 14 by the positive pressure of the net hopper 5. Since the entire amount of exhaust gas is circulated in this way, it is preferable to use the minimum amount of air necessary for combustion in the burner.

Note that in order to effectively utilize the high-temperature gas discharged from the discharge flue 14, a heat exchanger 15 is provided to heat the exhaust gas in the circulation flue 9 and recover heat. The high-temperature gas to be released may not be passed through the heat exchanger 15, but may be sent to the hot hopper side of a dryer for heating new aggregates in a known asphalt plant. In this case, hot air of about 800° C. will be sent to the new aggregate heating dryer, and can be effectively used for heating the new aggregate.

[Effects of the Invention] As described above, according to the asphalt waste recycling apparatus according to the present invention, the entire amount of exhaust gas derived from the drum 3 is returned to the combustion chamber 7 and reheated, and odor components and blue smoke contained in the exhaust gas are removed. It can be thermally decomposed to make it odorless, completely preventing it from harming the surrounding environment with its unpleasant odor.

In addition, the high temperature gas led out from the discharge flue 14 is transferred to the heat exchanger 1
If the waste heat is recovered through a dryer (5) or supplied to the hot hopper side of a dryer in a known asphalt plant to heat new aggregate, the waste heat can be effectively used and it is economical.

[Brief explanation of drawings]

FIG. 1 is a partially longitudinally sectional schematic explanatory diagram of an embodiment of the asphalt pavement waste recycling apparatus according to the present invention.

Claims (3)

[Claims] (1) A burner with a combustion chamber is installed on the hot hopper side at one end of the drum that heats and regenerates asphalt pavement waste, while an exhaust fan is installed in the middle of the circulation flue connected to the cold hopper side at the other end of the drum. an asphalt pavement waste recycling device, characterized in that the end of the circulation flue is connected to the combustion chamber, and the hot hopper is provided with a discharge flue for releasing a part of the gas in the drum to the outside. . (2) The circulation flue and the discharge flue intersect, and a heat exchanger is disposed at the crossing point to heat the exhaust gas in the circulation flue with the high temperature gas of the discharge flue.
The asphalt pavement waste recycling device described. (3) The asphalt pavement waste recycling apparatus according to claim 1, wherein the discharge flue is connected to a burner side of a dryer that heats the new aggregate.