JPS62259911A - Coal dust flying preventing method - Google Patents

Abstract

PURPOSE:To discharge water all over a coal storage heap through a small number of water discharge devices, by a method wherein an angle of elevation is specified at the central part of fan-shaped movement, and is gradually increased at both side parts. CONSTITUTION:When an arm-shaped part 6 is gradually rocked upward at both side parts of fan-shaped movement, an angle of elevation of a water discharge surface X, formed through fan-shaped rotation of a nozzle 8, with a horizontal plane is increased over alpha and is gradually increased to a high value betatoward the both sides of the fan-shaped movement, and after the nozzle 8 is turned over, a value is restored from beta to alpha. As a result, the flow of water discharged through the nozzle 8 is gradually risen approximately to a vertical state at both side parts of the fan-shaped movement, and a water discharge angle is gradually restored to its original value toward the central part. Thereby, when a water discharge flow approaches a ridge line, it is prevented from direct collapsion with the coal storage heap 1, and the water discharge flow is moved upward, and discharge of water to the upper surface of the coal storage heap 1 is continued as it is prevented from direct collapsion with the coal storage heap 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for preventing scattering of coal dust in outdoor coal storage areas in call centers, coal-fired power plants, etc.

(Conventional technology) Currently, Japan is trying to diversify its energy sources, and coal is seen as a link to this, but especially coal imported from overseas contains a large amount of particles with small particle sizes. Because of this, the scattering of coal dust from coal storage yards is attracting attention as a pollution problem. For this reason, methods are being considered to prevent the scattering of coal dust by concealing the coal by storing it indoors or storing it in silos, but this is not practical because the equipment costs would be enormous if there are many piles of coal stored.

Therefore, outdoor coal storage is carried out in call centers and coal-fired power plants where there are large piles of coal stored.
As shown in the publication, a water spray device with nozzles that rotate in a fan shape is installed around the coal pile at a constant pitch, and when the wind is weak, water is injected directly toward the coal pile, and when the wind is strong, the elevation angle of the nozzle is increased. A method to prevent coal dust from scattering has been adopted in which water is sprayed vertically and the wind blows it toward the coal pile.

However, in this method, in order to spray water over the entire long coal pile with as few water spray devices as possible, in times of weak winds, the nozzles of each water spray device are fan-shaped at a wide angle around an axis tilted with respect to the horizontal plane. Because of the rotation, the water ejected from the nozzle directly hits the sides of the coal pile on both sides of the fan-shaped movement, and the speed of the nozzle tip is also lower on both sides of the fan-shaped movement than in the center. There was a problem in that a large amount of water concentrated on specific parts of the coal storage, causing landslides.

For this reason, water is released! Attempts have been made to reduce the fan rotation angle of individual nozzles by increasing the number of nozzles, but this increases equipment costs and running costs in large-scale coal storage, so the above method is not possible without adding water spray equipment. There was a need for a method for preventing coal dust scattering that could solve the drawbacks of coal dust.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems and sprays water throughout the coal storage using a small number of water spraying devices without causing landslides in the coal storage during weak winds. This was completed with the aim of creating a method to prevent coal dust from scattering.

(Means for Solving the Problems) The present invention provides a water discharge surface formed by the fan-shaped rotation of the nozzle when water is discharged into the coal storage while rotating the nozzle of a water discharge device disposed around the coal storage in a fan-shaped manner. It is characterized in that the angle of elevation that it makes with respect to the horizontal plane is constant in the center of the fan-shaped motion, and gradually increases on both sides of the fan-shaped motion.

Next, the present invention will be described in detail with reference to the illustrated embodiments.
In FIG. 1, (1) is inside the coal storage, and (2) is a large number of water discharging devices installed around it. As shown in Figures 2 and 3, each water discharging device (2) is equipped with a pipe (5) that can be rotated through a small angle by a first motor (4) around a horizontal support shaft (3). An arm-shaped part (6) is connected to the pipe (5), and the arm-shaped part (6) is rotated in a fan-shaped manner around the central axis of the arm-shaped part (6) by a second motor (7). The shaft portion (8a) of an L-shaped nozzle (8) is attached. This nozzle (8)
As shown in Fig. 2, high-pressure water supplied from the pipe (5) is stored in the coal while repeating fan-shaped rotational motion around the inclined arm-shaped part (6) by a control mechanism such as a limit switch (not shown). The water is discharged toward the inside (11), and as shown in Figure 3, the angle of elevation of the water discharge surface (X) formed by the fan-shaped rotation at this time with respect to the horizontal plane is kept at a constant value α. However, in the present invention, a detector for the fixed rotation angle of the nozzle (8), such as a limit switch (9), is attached to the base of the nozzle (8), and the nozzle (8) is When the part of the water discharge reaches the position just before directly hitting the coal storage [11], the first motor (4) is activated to gradually swing the arm-shaped part (6) upward as shown by the solid line in Fig. 3. and then turn the nozzle (8
) reaches the end of the fan-shaped movement, the arm-shaped part (6) is gradually swung downward, and the arm-shaped part (6) to the angle shown by the imaginary line in Figure 3. When the arm-shaped portion (6) is gradually swung upward on both sides of the fan-shaped movement in this way, the angle of elevation of the water discharge surface (X) formed by the fan-shaped rotation of the nozzle (8) with respect to the horizontal plane is greater than α. is large and becomes a gradually larger value β toward both sides,
After the nozzle (8) is reversed, it returns from β to α. As a result, as shown in Fig. 4, the nozzle (8)
The water discharge from the fan-shaped movement gradually rises nearly vertically on both sides, and as it returns to the center, it returns to the original water discharge angle. directly call coal mountain fil
Therefore, according to the present invention, the water discharge flow moves upward and continues to discharge water to the upper surface of the coal storage (11) while avoiding direct impact with the coal storage +11. Therefore, according to the present invention, the rotation angle width of the fan-shaped movement is simply The width of the water spray from each nozzle (8) can be made sufficiently larger than when the angle is made smaller, and it is also possible to prevent landslides from occurring unlike the conventional method in which water is sprayed within a fan-shaped rotating plane with a constant elevation angle α. There is no possibility that this will occur.

In addition, when the wind is strong, the first motor (4) is operated to raise the nozzle (8) to an elevation angle of 75'' to 90°, as in the past, and water is sprayed while rotating the nozzle in a fan-shape in a nearly vertical plane. The wind pressure causes the coal to scatter inside the storage (towards 11).At this time, even if the limit switch (9) is activated, there is no need to operate the first motor (4).
The first motor (4) and the second motor (7) are preferably speed controllable, and in addition to using an electric motor, a fluid pressure drive device such as a water turbine or a rotary actuator can also be used.

Furthermore, the method of gradually increasing the angle of elevation of the water discharge surface formed by fan-shaped rotation of the nozzle with respect to the horizontal plane on both sides of the fan-shaped movement is not necessarily limited to the method described above. Guide plates are installed on both sides of the rotating surface to deflect the water flow from the nozzle (8) upward, and the nozzle is rotated in a fan shape within a fixed plane while deflecting only the direction of the water flow. The same effect can be produced by changing the angle of elevation that the fan-shaped rotating surface makes with respect to the horizontal plane.

(Effects of the Invention) As is clear from the above description, the present invention gradually increases the angle of elevation of the water discharge surface formed by the fan-shaped rotation of the nozzle with respect to the horizontal plane on both sides of the fan-shaped movement, thereby reducing the This system prevents the water from directly hitting the coal pile at times, and since each nozzle can have the same wide water spray width as before, there is no need to install additional water spray equipment, and when strong winds occur, the system can maintain the same wind pressure as before. Therefore, the present invention has the advantage of being able to perform water injection using the conventional methods, and therefore, the present invention can greatly contribute to the development of industry as a method for preventing scattering of coal dust that solves the conventional problems.

[Brief explanation of drawings]

Fig. 1 is a layout diagram of the water discharging device according to the present invention, Fig. 2 is a front view showing an example of the water discharging device used in the present invention, Fig. 3 is a side view thereof, and Fig. 4 is a diagram showing the relationship between the water discharging surface and coal storage. FIG. 3 is a perspective view showing the relationship. (1): During coal storage, (2): Water discharge device, (8): Nozzle,
(X): Water discharge surface. Patent applicant: Nippon Insulator Co., Ltd. Representative name: Akira Shima Buma
Watanuki Tatsu separation
Yama Rei Bun Huo Figure 1 1': ¥! r Tomoyama 2: & Water device 8; Nomata 1ru X: Water discharge surface Figure 2

Claims (1)

[Claims] When discharging water toward the coal pile while rotating the nozzle of a water discharge device installed around the coal pile in a fan-shaped manner, the elevation angle that the water discharge surface formed by the fan-shaped rotation of the nozzle makes with respect to the horizontal plane is the central part of the fan-shaped movement. This is a method for preventing coal dust scattering, which is characterized in that it is constant and gradually increases in size on both sides of the fan-shaped movement.