JPS5823792Y2 - Material discharge device in storage tank - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a material discharge device for a material storage tank installed in an asphalt plant or the like.

For example, in an asphalt plant, a storage tank is installed to store gravel used as an asphalt aggregate material. Normally, the wet material is put into the storage tank and taken out from the material outlet at the bottom of the storage tank. The processed material is supplied to a dryer, heated and dried, and then sent to the next process.

From this, in order to reduce the drying heating energy in the dryer, it is desirable that the material taken out from the storage tank be a material with as low a water content as possible.

However, as shown in Figure 1, conventional storage tanks of this type have
A material input port 1a is opened at the center of the upper lid of the storage tank 1, and a material discharge port 1b is opened at the center of the bottom of the storage tank 1. Directly below and near the discharge port 1b, there is a conveyor 2 for transferring the fallen material. It has a structure in which it is installed.

According to the storage tank 1 having such a conventional structure, when a new material is initially introduced, since the water permeability of the material M being stored is good, the water adhering to the material flows into the lower layer and the gaps between the materials. After passing through the water and collecting at the bottom of the storage tank 1, it is discharged to the outside from a drain port (not shown), and when the material M is discharged, the material from which water has been separated by the water permeation forms an odor angle θ unique to the material. The material slides down the corner slope 3 and is taken out from the outlet 1b, thereby reducing the moisture content of the taken out material.

However, after the storage time of material M has passed to a certain extent, the slope 3
The following dead stock materials have reduced water permeability due to clogging with fine aggregate;
The slope 3 becomes an impermeable surface similar to a concrete slope, and as a result, the effectiveness of drainage from the bottom of the storage tank 1 decreases, and the material M in the lower layer has poor drainage (for example, the top layer ml
Water content ratio is 4, middle layer m2 + 77!3 + 77Z
The water content ratio of 4 is 5% each.

A distribution gradient of water content occurs, such as 6%, 7%, and 8% in the lowest layer m5.

For this reason, in the storage tank of the conventional structure, when discharging the materials, the material M'aj is taken out sequentially starting from the high moisture material, and therefore, there is a drawback that the water removal effect of the storage tank 1 is not sufficiently exhibited.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and the purpose of the present invention is to selectively discharge the material in the layer with a low water ratio in the storage tank material, and further, It is an object of the present invention to provide a material discharge device for a storage tank that can efficiently heat and dry even when the water content in the discharged material is high.

Hereinafter, the present invention will be explained based on an illustrated embodiment.

In the discharge device of the embodiment, as shown in FIG. 2, a material input port 5 and a material discharge port 6 are provided at the center of the top lid 4a and bottom portion 4b of the storage tank 4, similar to the conventional structure described above. , and directly below the discharge port 6, a metering feeder 7 for transferring the discharged material is installed.

Further, in the center of the storage tank 4, a cylindrical chute 8 is erected with the bottom opening serving as the discharge port 6 and the discharge port 6 protruding slightly downward from the central hole 4c of the bottom 4b of the storage tank 4. In addition, the top opening of the chute 8 is covered with a roof-shaped baffle plate 9 supported on the inner wall of the storage tank 4, so that material falling from the input port 5 does not fall directly into the chute 8. It looks like this.

In addition, upper and lower gates 8a and 8b for material inflow are opened in the intermediate height and lower peripheral walls of the chute 8(1), and annular upper and lower doors j01 are opened in each of the gates 8a and 8b.
1.1 is slidably circumscribed, and the gates 8a and 8b are opened and closed by raising and lowering the doors 1o and ii.

Further, the lower door 11 extends downward from the lower gate 8b and passes through the center hole 4c of the bottom portion 4b, and its hem is folded back to the front side to form a drainage gutter 12, which includes: A drain pipe (not shown) is provided to conduct water to the outside.

However, the upper door 10. The lower door 11 is attached to the outer wall of the chute 8 at the upper and middle heights, respectively, and is supported by the working arm of a pneumatic or hydraulic cylinder 13.14 as an operation drive means. 14 to open and close.

In addition, at the bottom of the storage tank 4, there is a drainage pipe 1 whose open end protrudes outside the storage tank and has numerous pores along the entire length of the upper part.
．． A plurality of holes 5 are provided on the open end side, with the center hole 4 of the storage tank being inclined high on the c side.

In addition, moisture detectors 16, 17, and 18 are attached to the peripheral wall ρ, the upper part, the middle height, and the bottom of the storage tank 4, respectively, and the detectors 16, 17 are inserted horizontally into the tank 4.
, 18 sensing sections 16a, 17a.

The tip of 18a is near the upper end of chute 8, upper gate 8a
and the lower game) has reached the closest point of 8b.

Furthermore, the output signals of each of the detectors 16, 17, and 18 are input to the control device 19, and the fuel flow rate command signal a and the material removal amount command signal A and the material removal amount command signal are summed by the same device 19 and output electrically. It is input to the fuel flow control section of the burner 20 of the supplied dryer and the rotation control section of the quantitative feeder 7.

Next, the operation of the discharge device of the embodiment configured as above will be explained.

When taking out the materials, the order in which the stored materials M are taken out is
It is operated to eject from the soil layer to the lower layer, and specifically: (a) When the stored material M is above the ammonium angle slope 21 of the top opening of the chute 8; , keep both doors closed.

(b) When the material M is between the slope surface 21 and the angle of repose slope 22 relative to the upper gate 8a, operate the cylinder 13 to open the upper door 10 and keep the lower door 11 closed. .

(c) Material M is a slope 22. ,,<7J: When descending, operate the cylinder 14 to open the lower door 11.

By operating in this way, the material in the layer with the lowest moisture content in the storage material M can be discharged, and therefore, while the upper layer low moisture material is being discharged, the draining time for the lower layer high moisture material can be reduced. Stretching makes it possible to reduce the water content of the entire feed material.

Moisture accumulated at the bottom of the storage tank during storage of the materials is discharged to the outside through the drain pipe 15 or the drain gutter 12 of the lower door 11.

: In a conventional dryer that works together with a storage tank, there is a bar on the outlet side of the dryer depending on the temperature of the heating material.
．． Since the fuel flow rate was controlled at , the above-mentioned example contains the following 7 sections.
It has been desired to control the dryer by factors on the inlet side of the dryer, namely the feed rate of the feed material and the moisture content of the same material.

However, an instantaneous moisture detector is required for rounding to detect the moisture content during the supply and transfer process of the material.Moreover, instantaneous moisture detectors are expensive and have technical problems. As a result, it had not been put into practical use.

First, the moisture detectors 16, 17, and 18 with the above configuration statically measure the moisture in the material layer, so it is possible to use a detector with a simple structure and low cost. Based on the detected values of the water content ratio of the detectors 16, 17.18, the supply amount by the feeder 7 and the fuel flow rate of the burner 20 can be controlled in advance via the control signals a and b. In the case of the discharge device of the embodiment, there is an advantage that the drying operation control in the dryer is performed stably. Therefore, even when the moisture content of the material changes due to gate shift, the drying operation of the dryer can be controlled. It never drops.

In addition, in the configuration of the example (・), the number of gate stages is set to 3.
The shoe 1-8 may be formed in a cage form with an open upper end.

As mentioned above, according to the device for discharging material into a storage tank according to the present invention, a chute that communicates with the discharge opening is installed vertically in the tank, and the chute is selectively installed at different heights on the circumferential wall of the chute. By installing a multi-stage cage that can be opened and closed, it not only reduces the moisture content of the discharged material, but also makes it possible to practically detect the moisture content of the discharged material. In addition to reducing energy consumption, this method also has the effect of providing advance control over heating drying operations.

In addition, according to the present invention, moisture detectors are installed at multiple locations above and below the chute outer peripheral wall in the storage tank, so that the moisture in the upper and lower layers of the storage tank meat material can be statically detected at all times. By opening the gate corresponding to the layer with low moisture content, the material in that layer can be discharged as appropriate, and with a simple and inexpensive structure, the material with low moisture content can be discharged and used preferentially over the storage tank. effective.

Furthermore, according to the present invention, it is possible to accurately know the moisture content of a predetermined discharged material layer from the output signal of the moisture detector, so that the amount of material supplied by the feeder 7 and the fuel flow rate of the heating burner 20 in the subsequent process can be determined accurately. can be controlled in advance.

In particular, according to the present invention, a control device is provided that can vary the feeding speed of the feeder based on the output signal of each of the moisture detectors, so even when the moisture content of the material changes due to the transition between the upper and lower gates, the moisture content By slowing down the speed of the feeder when there is a large amount of drying, there is a practical advantage that the drying performance of the dryer is not reduced.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a conventional material discharge device for a storage tank, and FIG. 2 is a schematic cross-sectional view of a material discharge device for a storage tank showing an embodiment of the present invention. M...Material, 4...Storage tank, 4b...
... Bottom, 6 ... Discharge port, 7 ... Feeder, 8 ... Chute, 8 a, 8 b
-Gate, 10, 11 ・----・Door, 13゜14
...Opening/closing as operation driving means, driving cylinder, 16, 17, 18... Moisture detector, 19.
····Control device.

Claims (1)

[Scope of utility model registration request] In a material discharge device for a storage tank, the material being stored is appropriately discharged from a discharge port provided near the center of the bottom of the storage tank, and the material discharge device is provided vertically at a central position inside the storage tank, and a lower end opening is connected to the discharge port. a chute, a plurality of upper and lower stages of openable and closable gates that are opened at different heights on the circumferential wall of the chute, an operation and driving means for selectively opening and closing each gate, and a lower part of the chute. a feeder for discharged material installed in the storage tank, moisture detectors installed in multiple stages above and below along the outer peripheral wall of the chute inside the storage tank, and a discharge speed of the feeder based on the output signal of each moisture detector. A material discharging device in a storage tank, comprising: a control device that makes variable the control device;