JP2020186094A - Device for removing falling object and method for removing falling object - Google Patents

Abstract

To provide a device for removing a falling object applicable to a low floor conveyor and capable of cleaning and removing a falling object accumulated on an uppermost part of a gutter.SOLUTION: A device 10 for removing a falling object, which intermittently discharges a constant amount of cleaning water to an inclining gutter 30 provided below a belt conveyor to remove the falling object, includes: a shishi-odoshi type cleaning water discharge device 12 provided higher than the uppermost part of the inclining gutter; a nozzle header 22 which is provided at the uppermost part of the gutter and is provided with a nozzle extending in a width direction of the gutter to jet out the cleaning water obliquely downward in an upstream direction of the cleaning water flowing through the inclining gutter; and a piping for guiding the cleaning water, discharged from the shishi-odoshi type cleaning water discharge device, to the nozzle header.SELECTED DRAWING: Figure 1

Description

The present invention relates to a falling object removing device and a removing method for removing falling objects such as coal and coke that have fallen from a belt conveyor.

Once a conveyor belt fire occurs, it is difficult to extinguish it, the range of fire spread becomes large, and production is stopped, which is a problem. Conventionally, the following two patterns have been known as a mechanism for causing a belt conveyor fire.

As the first pattern, first, a large amount of coal is deposited up to the return roller on the gutter that receives the coal that has fallen from the belt conveyor, which makes it difficult for the return roller to rotate and the bearing generates heat, and the heat generating part. Ignite the coal in contact with the coal and generate a flame. The belt of the belt conveyor is hit by the flame, and finally the fire spreads to the belt, resulting in a belt conveyor fire.

In the second pattern, the bearing of the return roller is damaged and heat is generated, and the sparks of red hot pieces such as coal generated by the heat generated by the bearing fall and ignite the coal deposited on the gutter and cause a flame. Occur. The belt of the belt conveyor is hit by the flame, and finally the fire spreads to the belt, resulting in a belt conveyor fire.

In either pattern, the spread of fire to the belt can be prevented by removing the coal that has fallen and accumulated in the gutter. Therefore, in order to prevent the occurrence of a belt conveyor fire, it is important to promptly remove falling objects such as coal deposited on the gutter.

As a technique for removing falling objects such as coal deposited on a gutter, Patent Document 1 discloses a technique in which the uppermost portion of the gutter is modified into a lion threat and a large flow rate of water is intermittently flowed. Further, in Patent Document 2, a water storage tank in which the water supply port and the center are eccentric is separately provided upstream of the conveyor, and when a certain amount of water is stored in the water storage tank, the water storage tank rotates like a lion threat to rotate the water storage tank. A technique is disclosed in which the water inside is intermittently flowed into a gutter through a case and a discharge pipe.

JP-A-2007-269443 Utility Model Registration No. 3152811

However, the technique disclosed in Patent Document 1 requires a space for installing and operating a lion threat at the lower part of the belt of the belt conveyor, and therefore is applicable to a low-floor conveyor in which the height difference between the belt and the gutter is small. There was a problem that it could not be done. The technology disclosed in Patent Document 1 has not been applicable to low-floor conveyors, where fire prevention measures are required for low-floor conveyors, where the gutter and return roller are close to each other and the risk of fire on the belt conveyor is high. ..

Further, in the technique disclosed in Patent Document 2, although the lion threat can be applied to the low-floor conveyor by separating it from the gutter, the fall accumulated in the gutter range of about 100 mm upstream from the discharge pipe. There was a problem that the discharged water did not work well on the objects, and falling objects such as coal remained at the top of the gutter. The present invention has been made in view of these problems, and provides a falling object removing device and a removing method that can be applied to a low-floor conveyor and can also wash and remove falling objects accumulated on the top of a gutter. The purpose is.

The means for solving the above problems are as follows.
(1) A falling object removing device that intermittently discharges a certain amount of washing water to an inclined gutter provided below the belt conveyor to remove falling objects, and is more than the uppermost portion of the inclined gutter. A lion-threatening type washing water discharge device provided at a higher position and a washing water diagonally downward in the upstream direction of the washing water flowing in the gutter, which is provided at the uppermost part of the gutter and extends in the width direction of the gutter. A falling object removing device having a nozzle header provided with a nozzle for ejecting washing water, and a pipe for guiding the washing water discharged from the lion threatening type washing water discharging device to the nozzle header.
(2) The falling object according to (1), wherein the nozzle is a long rectangular slit along the width direction of the gutter, and the width of the slit is equal to or larger than the width obtained by subtracting 160 mm from the width of the gutter. Removal device.
(3) The center of the slit is located at a position where the angle clockwise around the center of the longitudinal vertical cross section of the nozzle header is 30 ° or more and 60 ° or less with respect to the direction perpendicular to the water flow direction of the trough. The falling object removing device according to (2), wherein a wire is provided.
(4) A method for removing falling objects by intermittently discharging a certain amount of washing water to an inclined trough provided below the belt conveyor, which is provided at a position higher than the uppermost portion of the inclined trough. The washing water is intermittently discharged from the lion-threatening type washing water discharge device to the trough, and the washing water flowing through the trough is inclined diagonally downward in the upstream direction from the nozzle header extending in the width direction of the trough. A method for removing falling objects by ejecting the washing water.
(5) The washing water is applied to the trough in a direction in which the clockwise angle around the center of the longitudinal vertical cross section of the nozzle header is 30 ° or more and 60 ° or less with respect to the direction perpendicular to the water flow direction of the trough. The method for cleaning a falling object according to (4), wherein the falling object is ejected.

The falling object removing device and the falling object removing method according to the present invention can also be applied to a low-floor conveyor, and the discharged water can flow to the uppermost part of the gutter. As a result, the falling objects accumulated on the top of the gutter can be effectively washed and removed.

It is an example of the falling object removing device 10 which concerns on this embodiment, and is the side sectional schematic diagram and perspective view which show the gutter 30. It is a schematic diagram of the apparatus used for confirming the relationship between the width of a slit nozzle 24, and the spread width of a nozzle discharge water 26. It is a graph which showed the relationship between the flow rate and the gap of a slit nozzle 24. It is a graph which shows the relationship between the flow rate and the gap of a slit nozzle 24 when the above-mentioned gutter 30 is used. It is a side schematic view which shows the positional relationship between the nozzle header 22 and the gutter 30 in the falling object removing device used for a test. It is an enlarged view of the part (A) of FIG.

Hereinafter, the present invention will be described through embodiments of the present invention. FIG. 1 is an example of a falling object removing device 10 according to the present embodiment, and a schematic side sectional view (FIG. 1 (a)) and a perspective view (FIG. 1 (b)) showing a gutter 30. The gutter 30 is a groove-shaped member provided directly below a belt conveyor that conveys a raw material such as coal, and is arranged so as to be inclined so as to cause a height difference at both ends. Falling objects such as coal that have fallen from the belt conveyor are deposited on the gutter 30. As described above, the falling objects accumulated on the gutter 30 may cause a fire on the conveyor belt. Therefore, the cleaning water is periodically poured from the falling object removing device 10 into the gutter 30 to wash the accumulated falling objects such as coal. And remove.

The falling object removing device 10 includes a lion threatening type washing water discharge device 12, a nozzle header guide pipe 20, and a nozzle header 22. The lion threatening type washing water discharge device 12 is provided at a position higher than the uppermost portion of the gutter 30. The lion threatening type washing water discharge device 12 has a water supply port 14, an external tank 16, and a trough 18. Water is supplied from the water supply port 14 and stored in the trough 18 as wash water. When a certain amount of washing water is stored in the trough 18, the trough 18 rotates in a lion-threatening manner, and the certain amount of washing water stored in the trough 18 is discharged from the external tank 16. The trough 18 from which the wash water has been discharged rotates in the reverse direction and returns to the original position, water is supplied from the water supply port 14 again, and the wash water is stored in the trough 18. By repeatedly storing and discharging water by the trough 18, a certain amount of washing water is intermittently discharged from the lion threatening type washing water discharging device 12.

A nozzle header 22 extending in the width direction of the gutter 30 is provided above the uppermost portion of the gutter 30. The wash water discharged from the lion threatening type wash water discharge device 12 is guided to the nozzle header 22 by the nozzle header guide pipe 20. The nozzle header 22 is provided with a slit nozzle 24 for ejecting wash water diagonally downward in the upstream direction of the discharged water flowing through the gutter 30 along the width direction of the gutter 30. The washing water guided to the nozzle header 22 is ejected from the slit nozzle 24 toward the uppermost portion of the gutter 30 through the nozzle header guide pipe 20. In the present embodiment, the washing water ejected from the slit nozzle 24 is defined as the nozzle discharge water 26.

As described above, in the falling object removing device 10 according to the present embodiment, the washing water is ejected diagonally downward in the upstream direction of the washing water flowing through the inclined gutter 30 as the nozzle discharge water 26. As a result, the nozzle discharge water 26 can be applied to the falling object deposited on the uppermost portion of the gutter 30 (a range of about 100 mm upstream of the discharge pipe described in Patent Document 2), which could not be sufficiently cleaned by the conventional technique. The fallen objects accumulated at the position can be washed and removed.

Next, the width of the slit nozzle 24 and the spread width of the nozzle discharge water 26 will be described. Here, the longitudinal direction of the slit nozzle 24 is referred to as a width, and the vertical width of the slit nozzle 24 is referred to as a gap. The gap between the slit nozzles 24 was constant in the width direction. FIG. 2 is a schematic view of an apparatus used for confirming the relationship between the width of the slit nozzle 24 and the spread width of the nozzle discharge water 26. The nozzle header 22 is installed so that the height of the slit nozzle 24 is 100 mm from 40 on the ground, the amount of water is changed to eject the nozzle discharge water 26 from the slit nozzle 24, and the spread width of the nozzle discharge water 26 on the ground 40 is measured. did. The test conditions and test results are shown in Table 1 below.

As shown in Table 1, it was found that the spread width of the nozzle discharge water 26 spreads by at least 167 mm before reaching the ground 40 100 mm below. From this result, the length of the slit nozzle 24 was set to be equal to or larger than the width of the gutter 30 minus 160 mm.

Next, the flow rate of water flowing through the gutter 30 will be described. It is known that a water flow velocity of 0.6 m / sec or more is required to allow water to flow without depositing sediment. Since coal has a lower specific gravity than earth and sand, it is considered that the coal deposited on the gutter 30 can be sufficiently washed and removed if the flow velocity of the water flowing through the gutter 30 is 0.6 m / sec or more. The average flow velocity V ₁ of the water flowing through the trough 30 may be the expression of Manning expressed by the following equation (1).

上記（１）式において、Ｒは水理学的平均水深（流れの断面積である流積を流れに接する固体壁の断面長さで除した値）であり、Ｉは水勾配であり、Ｖ_１は必要流速であり、ｎは粗度係数である。ここで、Ｖ_１＝０．６ｍ／ｓｅｃ（必要流速）とし、粗度係数ｎを０．０１２（鋼製の樋であることから鋼でライニングされた水路）とすると、水理学的平均水深Ｒは、下記（２）式で表すことができる。

In the above equation (1), R is the hydraulic average water depth (value obtained by dividing the flow volume, which is the cross-sectional area of the flow, by the cross-sectional length of the solid wall in contact with the flow), I is the water gradient, and V ₁ Is the required flow velocity and n is the roughness coefficient. Here, assuming that V ₁ = 0.6 m / sec (required flow velocity) and the roughness coefficient n is 0.012 (a water channel lined with steel because it is a steel gutter), the hydraulic average water depth R Can be expressed by the following equation (2).

Assuming that the width of the gutter 30 is Y, R is sufficiently smaller than Y. Therefore, R can be regarded as the height of the water flowing through the gutter 30. Therefore, the flow rate to _{Q 1} nozzle discharge water 26 flowing through trough 30 can be expressed by the following equation (3).

The design maximum flow rate Q ₂ of the gutter 30 was set as 3 times a safety factor against flow Q _1. Design maximum flow Q ₂ is can be expressed by the following equation (4).

Here, the maximum flow rate and the required flow rate will be described. In the present embodiment, the maximum flow rate means the maximum flow rate at the moment when the slit nozzle 24 can flow. The cross-sectional area of the slit nozzle 24 is A, when the cross-sectional area of the nozzle header 22 is B, if the cross-sectional area A is more than the cross-sectional area B, since the air opening synonymous, maximum flow rate, the maximum design flow rate Q ₂ Become. On the other hand, the cross-sectional area A is is less than the cross-sectional area B, the pressure loss is generated in the slit nozzle 24 the water fills the nozzle header 22, the maximum flow rate is less than the design maximum flow rate Q _2.

On the other hand, the required flow rate means a flow rate at which a flow rate of 0.6 m / sec can be maintained at the position of the slit nozzle 24. When the gap of the slit nozzle 24 is C, the required flow rate Q ₃ are can be represented by the following equation (5).

The gap between the slit nozzle 24 that maximizes the maximum flow rate and the remaining capacity of the required flow rate is the optimum gap between the slit nozzles 24, but this is when the cross-sectional area A of the slit nozzle 24 is equal to the cross-sectional area B of the nozzle header 22. is there. Therefore, assuming that the inner diameter of the nozzle header 22 is D, the following equation (6) holds, and the optimum gap C of the slit nozzle 24 can be expressed by the following equation (7).

Further, since the required flow rate Q ₃ is required to be less than the design maximum flow rate Q ₂ , the gap C of the slit nozzle 24 is limited to the range of the following equation (8).

FIG. 3 is a graph showing the relationship between the flow rate and the gap between the slit nozzles 24. The gap C of the slit nozzle 24 is preferably the optimum gap πD ² / {4 × (Y−0.16)} that maximizes the remaining force, and the gap limit value 1.8Y / {(Y−). It can be seen that it should be less than 0.16) × I ^3/4 }.

Next, the result of confirming the wall surface height of the gutter 30 will be described. This was performed using a gutter 30 having an inclination angle of 7 °, a width of 1560 mm, a wall surface height of 100 mm, and a total length of 55 m, which can be applied to a belt conveyor having a total length of 55 m. The water gradient I of the gutter 30 having an inclination angle of 7 ° and a total length of 55 m is 0.122.

(4) result of calculation using the equation, since the maximum design flow rate _{Q 2} was ^{8.6L / sec (0.52m 3 / min} ), a 10-fold 90L design maximum flow the capacity of the trough 18 , 15 L / min of water was supplied to the trough 18 from the water supply port, and the trough 18 was set to rotate in a lion-threatening manner once every 6 minutes, and the washing water was discharged to the external tank 16.

FIG. 4 is a graph showing the relationship between the flow rate and the gap between the slit nozzles 24 when the gutter 30 having the above-mentioned dimensions is used. The gap C of the slit nozzle 24 is most preferably 7.3 × 10 ^-3 m, which is the difference between the required flow rate and the maximum flow rate and has the largest residual capacity. Further, in order to make the required flow rate equal to or less than the design maximum flow rate, the gap C of the slit nozzle 24 needs to be less than 9.7 × 10 ^-3 m.

FIG. 5 is a schematic side view showing the positional relationship between the nozzle header 22 and the gutter 30 in the falling object removing device used in the test. As shown in FIG. 5, the diameter of the nozzle header 22 is 100 A, and the nozzle header 22 is installed so that the position 110 mm downstream from the uppermost portion of the gutter 30 is the center of the nozzle header 22.

FIG. 6 is an enlarged view of part (A) of FIG. The angle of the slit nozzle 24 will be described with reference to FIG. The angle of the slit nozzle 24 is the angle θ ₁ shown in FIG. That is, the angle of the slit nozzle 24 is an angle θ ₁ (from the center of the nozzle header 22 to the center of the gap of the slit nozzle 24 in the longitudinal vertical cross section of the nozzle header 22 with reference to the direction perpendicular to the water flow direction of the trough 30. (Clockwise). The test was conducted by installing the nozzle header 22 so that the angle θ ₁ of the slit nozzle 24 was 45 °. The test conditions and test results are shown in Table 2 below.

As described above, the design maximum flow rate Q ₂ is 0.52 m ³ / min, so that the test number 12 corresponds to the test in which the nozzle discharge water 26 having the design maximum flow rate is flowed. As shown in Table 2, overflow water from the trough 30 at 1.20 m ³ / min and the test No. 14 is twice the maximum design flow rate _{Q 2} of the flow rate occurs. This result, by a wall surface height of the trough 30 and 100 mm, that does not occur overflow water from the trough 30 within the design maximum flow Q ₂ is confirmed.

Next, the angle of the slit nozzle 24 will be described. Using the test equipment used in the test in Table 2, only the angle of the slit nozzle 24 was changed, and the ejection status of the nozzle discharge water 26 and the cleaning and removal status of the fallen objects were confirmed. The test conditions and test results are shown in Table 3 below.

As shown in Table 3, when the angle of the slit nozzle 24 is within the range of 30 ° or more and 60 ° or less, water overflow from the gutter 30 does not occur, and all the falling coal deposited on the uppermost part of the gutter 30 It was washed and removed. On the other hand, when the angle of the slit nozzle 24 is 28 °, the ejected nozzle discharge water 26 bounces off the gutter 30 and scatters out of the gutter 30. Further, when the angle of the slit nozzle 24 was 62 °, water overflowed from the gutter 30. From these results, it was confirmed that the angle of the slit nozzle 24 is preferably 30 ° or more and 60 ° or less.

10 Falling object removal device 12 Lion threatening type washing water discharge device 14 Water supply port 16 External tank 18 Traf 20 Nozzle header guide piping 22 Nozzle header 24 Slit nozzle 26 Nozzle discharge water 30 Gutter 40 Ground

Claims (5)

It is a falling object removing device that intermittently discharges a certain amount of washing water to an inclined gutter provided below the belt conveyor to remove falling objects.
A lion-threatening wash water discharge device installed at a position higher than the top of the inclined gutter,
A nozzle header provided at the uppermost portion of the gutter and provided with a nozzle for ejecting the washing water diagonally downward in the upstream direction of the washing water flowing through the gutter, which extends in the width direction of the gutter and is inclined.
A falling object removing device having a pipe for guiding the washing water discharged from the lion threatening type washing water discharging device to a nozzle header. The nozzle is a long rectangular slit along the width direction of the gutter.
The falling object removing device according to claim 1, wherein the width of the slit is equal to or greater than the width obtained by subtracting 160 mm from the width of the gutter. The slit is provided with a center line of the slit at a position where the angle clockwise around the center of the longitudinal vertical cross section of the nozzle header is 30 ° or more and 60 ° or less with respect to the direction perpendicular to the water flow direction of the trough. The fallen object removing device according to claim 2. It is a method of removing falling objects by intermittently discharging a certain amount of washing water to an inclined gutter provided below the belt conveyor.
The lion-threatening type washing water discharge device provided at a position higher than the top of the gutter that is inclined intermittently discharges the washing water to the gutter and is inclined from the nozzle header extending in the width direction of the gutter. A method for removing falling objects, in which the washing water is ejected diagonally downward in the upstream direction of the washing water flowing through the gutter. The washing water is ejected to the trough in a direction in which the clockwise angle of the center of the longitudinal vertical cross section of the nozzle header is 30 ° or more and 60 ° or less with respect to the direction perpendicular to the water flow direction of the trough. The method for removing a falling object according to claim 4.

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