JPH0444Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention efficiently oxidizes the asphalt mixture inside a mixture silo used to store asphalt mixture produced in an asphalt plant. The present invention relates to an asphalt mixture oxidation prevention device in a mixture silo for preventing oxidation of asphalt mixture.

[Prior art] In an asphalt plant, asphalt mix material (hereinafter referred to as mix material) is produced by mixing dried and heated aggregate and high-temperature asphalt in a mixer, and this mix material is transferred to a skip conveyor, etc. The material is once transferred to a mixed material silo and stored using a transfer device, and then transferred to a truck or the like as appropriate to be transported to the site. This mixed material silo is equipped with a heating device to maintain the fluidity of the mixed material inside, and measures are taken to prevent deterioration of the mixed material due to oxidation. An example of this is shown in FIG. 3, in which the opening of the hopper section 2 at the bottom of the silo 1 is covered with a sealed box body 3 equipped with a sliding opening/closing gate 4, and a gas cylinder is inserted into the box body 3 through a valve 5. 6 to supply inert gas.

[Problems to be solved by the invention] However, in such a conventional composite material oxidation prevention device, the opening of the hopper part 2 that discharges the composite material is covered with the box body 3, so the structure is complicated. Also, the slide gate 4 attached to the box body 3
This was very uneconomical as there was a lot of gas leakage from sources, etc., and inert gas had to be supplied in excess of the amount of gas leaking.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention includes an upper cylindrical part and a hopper part whose diameter decreases downward from the cylindrical part. In the mixed material silo, which stores the asphalt mixture supplied from the input port at the top and discharges it from the lower end of the hopper, on the inner surface of the boundary between the cylindrical part and the hopper part, diagonally below the inner wall of the cylindrical part. A projecting eave plate is formed along the circumferential direction, and a supply pipe for an inert gas having a specific gravity higher than that of air is opened in a space below the eave plate.

[Function] In such a composite material oxidation prevention device, when an inert gas such as carbon dioxide gas is supplied to the space under the eaves board, this gas descends along the inner wall of the hopper and damages the composite material in the hopper. Then, it gradually penetrates between the composite materials of the cylindrical part, filling the gaps between the composite materials, and further forms an inert gas film so as to cover the upper surface of the composite materials. Furthermore, when the hopper is opened, inert gas descends to prevent oxidation of the composite material in the hopper.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

Figure 1 shows the mixed material silo, silo 11.
consists of an upper cylindrical part 12 and an inverted conical hopper part 13 at the lower part of this cylindrical part 12, and the silo 11
Asphalt mixture is supplied from an input port 14 from a skip conveyor (not shown) running above the
A gate 15 provided at the lower end of the hopper section 13 is opened and closed to discharge the mixed material onto a truck or the like. The outer sheath 16 of this silo 11 has a layered structure with a heat insulating material 18 arranged between steel plates, and heaters (not shown) are provided at appropriate locations to maintain the internal temperature. A seal with an oil reservoir is used to keep the opening and closing part airtight.

On the inner surface of the boundary between the cylindrical part 12 and the hopper part 13 of this silo 11, an annular eave plate 19 is provided which projects diagonally downward from the inner wall 17a of the cylindrical part 12, with its upper end tightly fixed to the inner wall 17a. The lower end of the eave plate 19 is fixed to the inner wall of the hopper section 13 by an appropriate number of spacers 20 attached in the circumferential direction, and is supported substantially parallel to the inner wall surface of the hopper section 13. A gas supply pipe 21 that penetrates the outer cover 16 is opened in the space R under this eave plate 13, and this supply pipe 21 is connected to the flow rate regulating valve 2.
2, and a carbon dioxide gas cylinder 24 via a cutoff valve 23.
... has been contacted.

Next, the action of the mixture oxidation prevention device in the mixture silo configured as described above will be described.

After the mixture is inputted from the input port 14 and the input port 14 is closed, the cutoff valve 23 is opened, the flow rate adjustment valve 22 is adjusted appropriately, and carbon dioxide gas is released from the cylinder 24 into the annular shape under the eaves plate 19. is supplied to the space R of. This carbon dioxide gas fills the gap between the composite materials in the hopper section 13 of the silo 11. Since the lower end of the hopper part 13 is liquid-tightly sealed by the gate 15, gas will not leak out from the gate 15. Furthermore, this inert gas reaches above the eaves plate 19, penetrates into the composite material of the cylindrical part 12, replaces the air in the gaps between the composite materials, and eventually forms a film to cover the top surface of the composite material, It also fills the space above the composite material.

In this state, gate 15 is used for discharging the composite material.
When the gate 15 is opened, the inert gas inside the silo 11 flows downward together with the mixed material, and the inert gas inside the silo 11 flows downward from the gate 15.
Outside air does not flow into the interior of 1.

In this embodiment, since the eaves plate 19 is provided in an annular shape, the gas flows evenly and the gas flow does not sag, and the annular space R is provided above the hopper part 13. Therefore, the inert gas flows downward along the inner wall 17b of the hopper section 13 and is replaced without mixing with the air in the section. This has a small amount of composite material, and the top surface is 1
The same applies to cases where the number is lower than 9. Furthermore, since the eaves board 19 projects diagonally downward, the eaves board 19 does not obstruct the descent of the composite material.

FIG. 2 shows another embodiment of the present invention.
Eaves plate 19 approximately parallel to the inner wall surface of the hopper part 13
a... are fixed at their upper ends to the inner wall 17a of the cylindrical portion 12, and are provided in plural at intervals in the circumferential direction. On both sides of each eave plate 19a, there are side plates 2 that connect the eave plate 19a and the inner walls 17a, 17b.
5... are provided, and a space R'... surrounded by the eave plate 19a, inner walls 17a, 17b, and side plates 25 is formed below each eave plate 19a, and this space R'...
A branch pipe 27 of an annular gas supply pipe 26 provided on the outside of the outer jacket 16 is inserted into each of the pipes 1 and 2 and opened. In this example, the operation is similar to that of the previous example, but the reduction in the internal volume of the silo 11 is small, and the downward flow of the mixed material is not obstructed.

In order to prevent the temperature from decreasing due to the injection of inert gas, a part of the gas supply pipe 21 is preheated by being arranged in parallel with a heat-retaining heater attached to the outer wall of the hopper section 13.

[Effects of the invention] As detailed above, the present invention includes an upper cylindrical portion and a hopper portion whose diameter decreases downward from the cylindrical portion, and the hopper portion is supplied from the upper input port. In a composite silo that stores asphalt composite material and discharges it from the lower end of the hopper, a canopy plate extending diagonally downward from the inner wall of the cylindrical part is installed along the circumferential direction on the inner surface of the boundary between the cylindrical part and the hopper part. The structure is such that an inert gas supply pipe is opened in the space below this eave board, so inert gas is infiltrated from below into the gaps between the composite materials inside the silo.
Oxidation of the composite material can be effectively prevented by simple means.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a perspective view showing another embodiment of the present invention, and FIG. 3 is a sectional view showing a conventional example. 11... Silo, 12... Cylindrical part, 13... Hopper part, 14... Inlet, 19, 19a... Eaves plate, 21, 26... Supply pipe, R, R'... Space.

Claims (1)

[Scope of utility model registration request] The hopper part has an upper cylindrical part and a hopper part whose diameter decreases as it goes downward from the cylindrical part, and stores the asphalt mixture supplied from the upper input port and discharges it from the lower end of the hopper. In the silo, on the inner surface of the boundary between the cylindrical part and the hopper part, an eave plate is formed along the circumferential direction and extends diagonally downward from the inner wall of the cylindrical part, and the space below the eave plate is inert. An asphalt mixture oxidation prevention device in a mixture silo, characterized in that a gas supply pipe is open.