JPH0583681B2 - - Google Patents

Description

[Detailed description of the invention]

【0001】

[Field of Industrial Application] The present invention relates to a method for preventing the adhesion of sticky dust generated during the recycling of asphalt pavement waste materials, and relates to a method for replacing or repairing existing asphalt pavement, and also for installing equipment buried under existing asphalt pavement. This prevents sticky dust that flows out with the flow of combustion gas during the recycling process of asphalt pavement waste generated from construction work, particularly during the heating process, from adhering to the inner wall of the downstream flue.

[0002]

[Prior Art] Clumps of asphalt pavement waste material (hereinafter referred to as "waste material") excavated by road construction are crushed mechanically using a crusher or the like, or after immersing the waste material in hot water or high-temperature steam. A thermal crushing method in which bonds are broken by mechanical stirring is used to produce granular aggregate particles with an asphalt coating on the surface of the aggregate, which is then fed to a dryer, which is a heating device, to soften the asphalt and improve its properties. recover,
Efforts are being made to recycle waste materials.

[0003] Normally, a dryer that heats waste materials consists of a freely rotatable inclined cylindrical drum, and the waste materials are fed into the drum and rolled along the inclination direction to flow down, while a burner is used to heat the drum. The waste material is heated by supplying combustion gas inside.

[0004]

[Problems to be Solved by the Invention] However, when using this method, fine particles in the waste material become dust and flow out together with the gas flow. This dust is attached to asphalt, which becomes sticky when heated, so it adheres to the inner wall of the downstream flue, especially the curved pipe, and if this is repeated, it will block the flue. , induces a decline in the capacity and function of the device. In addition, because the dust that flows out is sticky, bag filters, which are filtration and dust collection devices that use fiber filter media, cannot be used, and cleaning dust collection devices are mainly used, but compared to bag filters, dust collection The performance is also poor, and the current situation is that it cannot be said to be desirable from the standpoint of pollution prevention.

[0005]

[Means for Solving the Problems] The present invention has been made in view of the above points, and in order to solve the above problems, waste materials are supplied to a dryer, which is a heating device for asphalt pavement waste materials, and heated and regenerated. However, in the method of using an asphalt pavement waste recycling device in which scattered dust is captured by a cyclone dust collector installed downstream of the dryer and a bag filter downstream thereof, a device connected to the dryer to discharge exhaust gas is used. A supply pipe that mixes stone powder, which is a property restoring agent for waste wood, is connected to the exhaust gas outlet near the dryer in the flue, and the tip of the supply pipe is arranged so as to face the direction in which the exhaust gas flows out. Stone powder is force-fed into the pipe and thrown into the flue so that it is mixed into the gas flow coming out of the dryer, and the stone powder and dust coated with stone powder captured by the cyclone dust collector and bag filter are sent to the mixer. To provide a method for preventing the adhesion of sticky dust generated during the recycling of asphalt pavement waste material, which is characterized in that the reduced asphalt mixture is mixed into recycled asphalt mixture for use.

【0006】

[Operation] In the present invention, stone powder, which is a property restoring agent for waste wood, flows out from the supply pipe connected to the flue of the exhaust gas outlet near the dryer in the direction in which the exhaust gas flows out. As a result, the outflow of exhaust gas from the dryer can be facilitated.

[0007] Then, by force-feeding stone powder into the supply pipe and mixing the stone powder with the gas flow,
By coating the surface of the dust accompanying the gas flow with stone powder, the asphalt content can make the adhering dust non-adhesive, preventing the dust from adhering to the flue, downstream cyclone dust collector, bag filter, etc. can be prevented.

[0008] In addition, by reducing the stone powder and dust coated with stone powder captured by the cyclone dust collector and bag filter into the mixer and mixing it into the asphalt mixture to be recycled, the above-mentioned dryer can be used. This eliminates the waste of stone powder thrown in at the exhaust gas outlet.

【0009】

[Examples] The present invention will be explained below based on Examples. FIG. 1 shows one embodiment of the present invention. Reference numeral 1 denotes a dryer which is a heating device, and is of a rotary kiln type, in which a cylindrical drum 2 having a number of scraping blades (not shown) arranged around its inner periphery is pivotally supported at an angle. . 3 is a burner installed at one end of the drum 2, which sends combustion gas into the drum 2, and sucks the combustion gas through an exhaust fan 5 installed at the end of a flue 4 connected to the other end to blow the inside of the drum 2. Maintaining a hot gas flow through.

[0010] In addition, feeders 7a, 7b, 7, which are equipped with a control device and can freely take out a fixed amount from hoppers 6a, 6b, 6c, which store crushed waste material according to various particle sizes, are provided.
According to c, waste materials are taken out according to the type of asphalt mixture to be manufactured, and conveyed to belt conveyors 8 and 9.
The waste material is fed into the drum 2 through the drum 2, and is rolled and flowed down within the drum 2 to be heated to a desired temperature. The heated waste material is fed into the mixer 11 from the discharge section 10, and if necessary, the missing asphalt is replenished, and a softening agent, which is a property restoring agent, is added.
It is mixed with stone powder and adjusted before being shipped.

[0011] 12 is a stone powder storage bin that stores stone powder, and the stone powder discharged from the rotary valve 13 of the quantitative supply device provided at the lower discharge part is sent to the blower 1 for pressure feeding.
4, the gas is transferred through the supply pipe 15 and sent to the exhaust gas outlet of the flue 4 of the dryer 1. Reference numeral 16 denotes a constriction part provided at the exhaust gas outlet part of the flue 4, which narrows the cross-sectional area of the gas flow.
The stone powder is efficiently attached to the dust. 17 is a cyclone dust collector that captures coarse particles of dust flowing out; 18 is a bag filter that is a filter dust collector that captures fine particles of dust that are not captured by the cyclone dust collector; 19;
is a chimney.

[0012] Therefore, in order to regenerate waste material, waste material of a desired particle size is transferred to the feeder 7 according to the type of asphalt mixture produced from the hoppers 6a, 6b, and 6c.
Take out by a, 7b, 7c. Then, it is fed into the drum 2 via belt conveyors 8 and 9,
The scrap material is scraped up by scraping blades installed in the drum 2 while rolling and flowing down, while being heated by combustion gas from the burner 3, and the heated scrap material is transferred to the discharge section 10.
Then, put it into the mixer 11.

[0013] Accompanied by the gas flow passing through the drum 2, dust coated with sticky asphalt components flows out. However, the stone powder discharged in fixed quantities from the stone powder storage bin 12 via the rotary valve 13 is sent into the flue 4 via the supply pipe 15 using the pressure-feeding blower 14 to encourage the outflow of exhaust gas. The stone powder and the dust collide near the throttle part 16 provided in the flue 4, the stone powder is attached to the asphalt portion on the dust surface, and the dust surface is coated with the stone powder to make the dust non-adhesive.

[0014] The dust that has become non-adhesive passes through the downstream flue 4 without adhering to it, and the cyclone dust collector 17 removes the coarse part of the dust, and the bag filter 18 removes the fine part of the dust. At the same time, the stone powder not attached to the dust is also collected, and the purified gas is released into the atmosphere from the chimney 19. Since the stone powder used to cover the dust is mixed in to restore the properties of the asphalt mixture, the dust and stone powder captured by the cyclone dust collector 17 and bag filter 18 are returned to the mixer 11 and are wasted. It can be used without any problem.

【0015】

[Effects of the Invention] As described above, according to the present invention, stone powder, which is a material for restoring the properties of waste wood, can flow out from the supply pipe to the exhaust gas outlet part of the flue connected to the dryer, and the exhaust gas from the dryer can flow out. can be encouraged. Then, by mixing this stone powder into the gas flow led out from the dryer and coating the sticky dust accompanying the gas flow with the stone powder to make the dust non-stick, the dust is removed from the flue and downstream cyclone. It is possible to prevent dust from adhering to dust collectors, bag filters, etc., without causing a decline in the capacity or functionality of the device, and bag filters with high dust collection performance that use fiber filter media can be used, which is useful for pollution prevention. It is beneficial.

[0016] Furthermore, the stone powder used to coat the dust surface is originally mixed into the asphalt mixture, and the stone powder captured by the cyclone dust collector and bag filter, and the asphalt mixture recycled from the dust coated with stone powder, are used to coat the dust surface. Since it is mixed into the material and used, there is no waste.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway schematic explanatory diagram of an asphalt pavement waste recycling plant employing the method of the present invention. 1... Dryer 4... Flue 15... Supply pipe 17... Cyclone dust collector 18... Bag filter.

Claims (1)

[Claims] Claim 1: The waste material is supplied to a dryer, which is a heating device for asphalt pavement waste material, and is heated and regenerated, and the scattered dust is captured by a cyclone dust collector installed downstream of the dryer and a bag filter downstream thereof. In the method of using the asphalt pavement waste material recycling equipment, a supply pipe that mixes stone powder, which is a property restoring agent for waste material, is connected to the exhaust gas outlet near the dryer of the flue connected to the dryer to discharge exhaust gas. At the same time, the tip of the supply pipe is arranged so as to face the outflow direction of the exhaust gas, and the stone powder is forced into the supply pipe and thrown into the flue, so that the stone powder is mixed into the gas flow led out from the dryer. Asphalt pavement waste material recycling characterized in that the stone powder and stone powder-coated dust captured by the cyclone dust collector and bag filter are returned to a mixer and mixed into the recycled asphalt mixture for use. A method to prevent the adhesion of sticky dust that sometimes occurs.