JPH0128087Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an asphalt regeneration plant that regenerates asphalt pavement waste material to produce recycled asphalt composite material. Regarding asphalt regeneration plants.

As is well known, in a thermal crushing type asphalt regeneration plant, asphalt pavement waste material (hereinafter referred to as waste material) is fed into a steam box in large chunks, and the waste material manufactured using a steam boiler is placed inside this steam box. Steam is introduced, and the waste material is heated and crushed by its temperature and heat of condensation.
This heated and crushed waste material is then sent to a vibrating screen via a grizzly screen and sieved according to particle size, and then heated and mixed in a drum mixer to produce recycled asphalt composite material (hereinafter referred to as recycled composite material). By the way, since the waste material is heated in a steam box, it becomes sticky, and when it is sieved by the vibrating screen, it adheres to the sieving screen of the vibrating screen and solidifies. As a result, waste material may overflow from the sieving net or the sieving efficiency may decrease. Therefore, in the past, operators inspected the sieve net at appropriate intervals and removed the waste material adhering to the sieve net with a chisel, etc., as necessary, but this work was extremely troublesome, and the sieve net itself The damage was also severe.

The present invention solves the above-mentioned conventional problems by installing a spray device on the vibrating screen and spraying steam produced in a steam boiler onto the sieve screen to prevent clogging of the sieve screen. can easily and quickly remove clogging of the sieve mesh of the vibrating screen.
The purpose is to provide an asphalt regeneration plant with good operability.

The present invention will be explained below based on the drawings.

Figures 1 to 3 show an embodiment of the asphalt regeneration plant of the present invention.
A steam boiler 1 that produces steam s, a steam box 2 that heats and crushes waste material A using steam s produced by this steam boiler 1, and sieves the waste material A that has been heat and crushed in this steam box 2 according to particle size. It consists of a vibrating screen 3 and a drum mixer 4 that heats and mixes the waste material A screened by the vibrating screen 3.

The steam box 2 is an iron container with a lid, and a steam nozzle 2a for supplying steam s from the steam boiler 1 is provided in the middle part.
A screw conveyor 2b is connected to the lower part, and the waste material A introduced from the upper part is heated and softened by the temperature of the steam s jetted from the steam nozzle 2a and the heat of condensation, and is then softened by the screw conveyor 2b. The material is loosened appropriately and sent onto a belt conveyor 5 provided at a lower discharge port. Then, the waste material A sent onto the belt conveyor 5 is sent to a well-known grizzly screen 7 by another belt conveyor 6, where roadbed material etc. are removed, and then the waste material A is sent to a well-known grizzly screen 7 by a surge elevator 8. The signal is sent to the vibrating screen 3.

The vibrating screen 3 has a plurality of sieving nets 12a, 12b, 12c placed on a machine frame 11 which is elastically supported by a plurality of support members 10 via springs 9.
The waste material A is installed in a piled state with downstream passages m ₁ , m ₂ , m ₃ formed with a predetermined inclination in the flow direction and with meshes becoming smaller toward the bottom. By vibrating an oscillating body 13 attached to the machine frame 11 by a motor 14, the entire machine frame 11 is vibrated. The vibrating screen 3 is also equipped with a spray device 15. This spray device 15 is arranged above or below each of the sieve nets 12a, 12b, 12c of the vibrating screen 3 at an appropriate distance from each of the sieve nets 12a, 12b, 12c, and extends in a direction across the vibrating screen 2. A plurality of nozzle pipes 15a are fixedly attached to the machine frame 11 at appropriate intervals in the longitudinal direction of the vibrating screen 2, and each of the nozzle pipes 15a and the steam boiler 1 are connected via valves 24, flexible pipes, etc. Each sieve net 12a, 12b, 12c is connected by a connecting pipe 15b through an injection nozzle 23 provided along the longitudinal direction of the nozzle pipe 15a.
Steam s is injected toward each sieve net 12.
This prevents the waste material A from clogging a, 12b, and 12c.

Furthermore, the lower part of the vibrating screen 3 is provided corresponding to each sieve net 12a, 12b, 12c, and each flow passage m ₁ , m ₂ , m ₃ is provided to the lower end of the sieve net 12a, 12b, 12c. There are hot bins 16a, 16b, and 16c for receiving and storing the waste material A of each particle size that has flown down, and for receiving the waste material A that has passed through the mesh of the lowermost sieve screen 12c of the sieve nets 12a, 12b, and 12c. A hot bin 16d for accommodating this is provided respectively. Then, the waste material A of each particle size that comes out of each hot bin 16a, . A predetermined amount is measured in the measuring tank 21 and transferred to the mixer 22.
The structure is such that it can be mixed with new aggregate, asphalt, etc.

Next, the operation of the asphalt regeneration plant according to the present invention configured as described above will be explained.

In recycling the waste material, the waste material A is put into the steam box 2 while the steam boiler 1 is operated as in the conventional manner. The waste material A put into the steam box 2 is heated and softened by the temperature of the steam s injected from the steam nozzle 2a and the heat of condensation, and is discharged onto the belt conveyor 5 while being loosened by the screw conveyor 2b.
is sent to Grizzly Screen 7 by After the roadbed material and the like are removed by this grizzly screen 7, it is sent to the vibrating screen 3 by the surge elevator 8, and is sieved by particle size by each sieve net 12a, . . . , into each hot bin 16a,
It will be accommodated in... The waste material A stored in each hot bin 16a... is sent to the drum mixer 4 via belt conveyors 17, 18, where it is heated and mixed to become a recycled composite material. The recycled composite material thus generated is sent to the stock bin 20 of the asphalt plant by the skip conveyor 19, a predetermined amount is measured in the measuring tank 21, and mixed with new aggregate, asphalt, etc. in the mixer 22, and the asphalt composite material is becomes.

Here, the waste material A adheres to each sieve net 12a, . . . of the vibrating screen 3 due to its stickiness, and the sieve nets 12a, . The status of the networks 12a, . . . is checked at appropriate time intervals. Then, the valve 24 is opened as necessary to inject the steam s supplied from the boiler 1 through the connecting pipe 15b to each sieve net 12a, . . . . Then, the steam s is injected from the injection nozzle 23 at high speed.
Therefore, due to the temperature of the steam s and the heat of condensation, the waste material A
is heated and melted, and this molten waste material A is removed by steam s jetted at high speed.
In this way, the sieve net 12 of the vibrating screen 3
Even if a, . . . becomes clogged, the spray device 15 can easily restore the normal state.

By the way, in the above, a manual valve 24 is installed at a predetermined position of the connection pipe 15b of the spray device 15.
This is used as a control valve, and this control valve is linked to the operation of the vibrating screen 3, and is opened and closed at set time intervals by a timer, etc., so that the steam s is automatically injected. It is also easy to do. In addition, regarding the above,
The vibrating screen 3 includes a plurality of sieve screens 12a,...
... were arranged in a stacked manner so that the mesh size becomes smaller toward the bottom. However, in the flow direction of waste material A, multiple sieve nets are arranged in a stacked manner so that the mesh size becomes larger toward the downstream side. It may be something you have done.

As described above, in the asphalt regeneration plant of the present invention, a plurality of injection nozzles for injecting steam from the steam boiler onto the sieve screen are arranged on the vibrating screen over the entire surface of the sieve screen. The heat of condensation can be utilized, and a much larger amount of heat can be supplied to the sieve screen than when simply heating with a heating fluid.
Therefore, the waste material adhering to the sieve screen can be melted in a short time. Moreover, since the high-speed steam jetted from the jet nozzle can be applied to the entire surface of the sieve screen, the waste material melted by the steam can be immediately blown away by the steam. Therefore, the waste material attached to the sieve screen can be melted and removed in a short time, and the sieve screen of the vibrating screen can be easily and quickly cleared from clogging.
Operability is improved. Furthermore, since the steam introduced into the steam box is used as the steam supplied to the spray device, there is no need to separately install a new steam boiler, which is convenient.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a general schematic diagram of an asphalt regeneration plant, Fig. 2 is a side view of a partially broken vibrating screen, and Fig. 3 is a front view of the same. 1... Steam boiler, 2... Steam box, 3... Vibrating screen, 4... Drum mixer, 12a, 12b, 12c... Sieve net, 15
... Spray device, 23 ... Injection nozzle.

Claims (1)

[Scope of utility model registration request] A steam boiler that produces steam, a steam box that heats and crushes asphalt pavement waste using the steam produced by the steam boiler, and a vibration that sieves the asphalt pavement waste that has been heated and crushed in the steam box according to particle size using a sieve screen. In an asphalt regeneration plant comprising a screen and a drum mixer that heats and mixes the asphalt pavement waste sieved by the vibrating screen, the vibrating screen includes an injection nozzle that injects steam from the steam boiler onto the sieve screen. An asphalt regeneration plant characterized in that a plurality of asphalt regeneration plants are arranged over the entire surface of the sieve net.