JPH0940076A - Coal particle accumulation prevention device for CWM storage tank - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent damage to the descending plate and improve the work efficiency of the coal particle deposition prevention device. [Constitution] The downcomer pipe 12 and the ejection pipe 13 are CWM storage tanks 1.
CWM spun from the spout 20 to agitate the coal particles 17 deposited on the bottom plate 19 to prevent deposition by rotating around the central axis of the. Since the downcomer 12 rotates about the rotational displacement absorbing mechanism 22 in a direction opposite to the traveling direction of the downcomer 12 when the coal particles 17 are accumulated, the downcomer 1
The excessive force that 2 destroys does not act. Further, even when the downcomer pipe 12 receives horizontal hydraulic pressure by the liquid storage (CWM) 15 during an earthquake, the downcomer pipe 12 rotates about the rotational displacement absorbing mechanism 22 to absorb the displacement in the rotational direction. The excessive force that breaks the downcomer 12 does not act.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a CWM (Coal W
ater Mixture: a coal particle accumulation prevention device for a CWM storage tank for preventing coal particles from accumulating at the bottom of a storage tank for mixed powder of fine coal and water).

[0002]

2. Description of the Related Art CWM is a liquid produced by adding a small amount of an additive (surfactant) to coal obtained by finely pulverizing water and adding water, and used as a fuel, etc. Has been done. Examples of the physical properties of typical CWM are shown below. Content composition: water; about 30 wt. %: Coal (powdered coal); about 70 wt. %: Additive; about 0.5 wt. % Coal particle size: 500 μm or less; 99%: 150 μm or less; 94% Apparent viscosity: 900 ± 300 CP (at a temperature of 25 ° C. and a shear rate of 100 (l / S)) Specific gravity: 1.25 Calorific value: 5000 kcal / kg

When CWM is stored in a storage tank for a long period of time, coal particles settle and a deposit layer is formed on the bottom plate at the bottom of the storage tank. If left unattended, the accumulated layer gradually increases, causing various problems such as a decrease in the effective storage amount of the storage tank, clogging of the delivery pipe, and a huge cleaning work at the time of opening inspection of the storage tank. Conventional CWM
In the storage results of the storage tank, 1-2 m during the storage period of one year
There is also an example of the occurrence of deposits.

As a conventional technique for solving this problem, Japanese Unexamined Utility Model Publication No. 1-100795 discloses a device for preventing sludge accumulation (hereinafter referred to as "prior art").
FIG. 4 is a schematic front cross-sectional view showing the prior art, and FIG. 5 is a front view showing the state of coal particle accumulation in the vicinity of the ejection pipe. As shown in FIGS. 4 and 5, a liquid delivery pipe 9 is vertically provided at the center of the CWM storage tank 1, and a liquid delivery branch pipe 11 and downcomers 12, 12 are provided.
Can rotate about the rotary joint 10. A jet pipe 13 is provided at a lower end of each downcomer pipe 12 at a position close to a bottom plate 19 at the bottom of the CWM storage tank 1.
The ejection pipe 13 is horizontally provided in a direction orthogonal to the traveling direction of the cylindrical downcomer 12, and ejection ports 20 are provided at the tips of both ends of the ejection pipe 13. The liquid (CWM) 15 in the CWM storage tank 1 is discharged from both sides of the jet pipe 13 through the liquid suction pipe 2, the liquid feed pipes 4 and 9, the liquid feed branch pipe 11, the descending pipes 12 and 12 by the circulation pump 3. The coal particles 17 that are jetted from 20 in a direction orthogonal to the traveling direction of the downcomer 12 and are agitated and removed by the jetted CWM are deposited on the bottom plate 19.

[0005]

However, in the prior art, as shown in FIGS. 4 and 5, the effect of preventing the deposition of the jet flow does not extend below the jet pipe 13, so that the bottom plate 19 below the jet pipe is provided with coal. Accumulation of particles occurs, and the growth of the accumulation hinders the rotation of the ejection pipe 13. Further, if the rotation is continued in such a state, there is a problem that a large force acts on the traveling mechanism 18 and the downcomer 12, which causes damage.

At the time of an earthquake, the downcomer pipe 12 is C
There is also a problem that the liquid (CWM) 15 in the WM storage tank is damaged by being subjected to horizontal hydraulic pressure. For this reason, there is a problem in that it is necessary to reinforce another member on the outside of the downcomer pipe to increase the strength.

Therefore, an object of the present invention is to prevent damage to the downcomer pipe and the like due to coal particles accumulated on the bottom plate of the CWM storage tank during operation of the apparatus, and further to prevent damage to the downcomer pipe and the like due to external force such as an earthquake. It is to provide a coal particle deposition prevention device for a CWM storage tank that can be used.

[0008]

According to the present invention, above a liquid level of a CWM in a CWM storage tank, the center axis of the CWM storage tank, which is provided horizontally in the radial direction from the center axis of the CWM storage tank, is rotatable about the center axis. And a downcomer pipe having a lower end located at a position close to the bottom of the CWM storage tank, which is connected to the liquid branch pipe, and the liquid branch pipe and the downcomer pipe. A rotation mechanism for rotating about the central axis as a rotation center, and a CWM provided in a lower end portion of the downcomer pipe horizontally in a direction orthogonal to the traveling direction of the downcomer pipe, in a direction orthogonal to the traveling direction of the downcomer pipe. An ejection pipe having an ejection port for ejecting the CWM, the CWM in the CWM storage tank disposed outside the CWM storage tank is recovered, and the recovered CWM is ejected through the liquid delivery branch pipe and the downcomer pipe. Supply to pipe C consisting of a CWM circulation mechanism for
In the coal particle deposition prevention device for a WM storage tank, the downcomer pipe is connected to the liquid delivery branch pipe via a joint capable of angular displacement, and the joint allows an angle of the downcomer pipe with respect to the liquid delivery branch pipe. Is variable.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a schematic front sectional view showing an embodiment of the apparatus according to the present invention as a whole, and FIG. 2 is a view showing a downcomer portion.
It is a partially expanded side view of FIG.

As shown in FIG. 1, the CWM storage tank 1 is a bottom plate 1.
It is a circular storage tank provided with 9. Above the liquid level of the storage liquid (CWM) 15 stored in the CWM storage tank 1, the ceiling 6 of the CWM storage tank 1 penetrates through the center of the ceiling 6 and the liquid delivery pipe 9
Are arranged vertically. At the lower end of the liquid feed pipe 9, a vertical portion 11a vertically connected to the lower end of the liquid feed pipe 9 via a rotary joint 10 and a horizontal portion in the radial direction from the vertical portion 11a (that is, the central axis of the CWM storage tank). A horizontal portion 11b provided at
A liquid delivery branch pipe 11 including an end portion on the side wall 1a side of the horizontal portion 11b and vertical portions 11c and 11d provided in the middle is connected.

The downcomer 12 is connected to the lower end of the vertical portion 11c via a rotational displacement absorbing mechanism 22. Downcomer 12
Are vertically arranged in the liquid of the liquid storage (CWM) 15, leaving a part of the upper part. Similarly, a vertical portion 11d is provided in the middle of the horizontal portion 11b, and the downcomer pipe 12 is connected to the lower end of the vertical portion 11d via a rotational displacement absorbing mechanism 22. The number of downcomers is not limited to two, and can be increased according to the situation.

As shown in FIG. 1, at each of the lower ends of the downcomers 12, 12, a cylindrical ejection pipe 13 is horizontally connected in a position close to the bottom plate 19 in a direction orthogonal to the traveling direction of the downcomer 12. ing. Jet ports 20 are provided at both ends of the jet pipe 13. Both end portions of the ejection pipe 13 are provided in such a shape that the cross-sectional area thereof gradually decreases toward the tip.

On the lower surface of the ceiling 6 of the CWM storage tank 1, the ceiling 6
A rail 14 is laid around the periphery of the rail 14, and a traveling mechanism 18 is provided on the rail 14 so as to be able to travel.
The traveling mechanism 18 and the liquid supply branch pipe 11 are connected by the connection frame body 5. As the traveling mechanism 18 travels along the rails 14, the liquid delivery branch pipe 11 and the downcomer pipe 1
2 and 12 are rotatable in the CWM storage tank 1 with the rotary joint 10 as the center of rotation.

On the outside of the CWM storage tank 1, a side wall 1a
The liquid suction pipe 2 is connected to the lower portion, and further, the liquid feed pipe 4 is connected via the circulation pump 3, and the liquid feed pipe 4 is connected to the upper end of the liquid feed pipe 9. Reference numeral 21 is a valve provided in the liquid supply pipe 4.

The downcomers 12, 12 and the ejection pipe 13 are C
The traveling mechanism 18 rotates the center of the WM storage tank 1 (the rotary joint 10) as the center of rotation. The stored liquid (CWM) 15 stored in the CWM storage tank 1 passes through the liquid suction pipe 2, the liquid feed pipes 4, 9, the liquid feed branch pipe 11, the descending pipe 12, and the jet pipe 13 by the circulation pump 3 and the jet outlet 20. The coal particles 17 ejected from the bottom pipe 19 in a direction orthogonal to the traveling direction of the downcomer pipe 12 are agitated to prevent the coal particles 17 from being deposited.

Further, as shown in FIG. 2, when the coal particles 17 are accumulated, the downcomer pipe 12 can rotate about the rotational displacement absorbing mechanism 22 in the direction opposite to the traveling direction thereof.
The downcomer pipe 12 is prevented from being damaged without an excessive force that damages the pipe body.

Further, as shown in FIG. 3, even when the downcomer pipe 12 receives the horizontal hydraulic pressure 7 by the liquid storage (CWM) 15 at the time of an earthquake, the downcomer pipe 12 and the ejection pipe 13 have the rotational displacement absorbing mechanism. Since it rotates around 22 and absorbs the displacement in the rotational direction, the downcomer 12 is prevented from being damaged without being subjected to the excessive force.

The rotational displacement absorbing mechanism 22 as a joint capable of angular displacement is only required to be capable of absorbing the rotational displacement of the downcomer pipe 12 in the direction orthogonal to the pipe axis, and is specifically used for ordinary pipes or the like. Expansion joints and spherical joints (ball joints) can be applied.

[0020]

As described above, according to the present invention, the following industrially useful effects are provided. Even if coal particles are deposited on the bottom plate of the CWM storage tank, the joint that can be angularly displaced absorbs the displacement in the rotation direction of the downcomer pipe, so that the downcomer pipe is excessively damaged by the coal particles during operation of the device. You will not receive any power. Further, since the joint capable of angular displacement absorbs the displacement in the direction of rotation of the downcomer pipe, an excessive force is applied to damage the downcomer pipe when it receives horizontal hydraulic pressure due to the liquid storage (CWM) during an earthquake. Never. A large force does not act on the traveling mechanism and the downcomer pipe, and the device can be operated safely without fear of damage.

[Brief description of drawings]

FIG. 1 is a schematic front sectional view showing an embodiment of an apparatus of the present invention with an overall configuration.

FIG. 2 is a partially enlarged side view of FIG. 1 showing a downcomer portion.

FIG. 3 is a partially enlarged side view of FIG. 1 showing an embodiment of the present invention in a state during an earthquake.

FIG. 4 is a schematic front sectional view showing a prior art.

FIG. 5 is a front view showing a deposition state of coal particles in the vicinity of an ejection pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CWM storage tank 1a Side wall 2 Liquid suction pipe 3 Circulation pump 4 Liquid transmission pipe 5 Connection frame 6 Ceiling 7 Horizontal liquid pressure 9 Liquid transmission pipe 10 Rotating joint 11 Liquid distribution branch pipe 11a Vertical part 11b Horizontal part 11c Vertical part 11d Vertical part Part 12 Downcomer pipe 13 Jet pipe 14 Rail 15 Liquid storage (CWM) 16 Conduit 17 Coal particle 18 Traveling mechanism 19 Bottom plate 20 Jet outlet 21 Valve 22 Rotational displacement absorbing mechanism

Claims (1)

[Claims] 1. A liquid delivery branch pipe, which is horizontally provided in a radial direction from a central axis of the CWM storage tank above a liquid level of the CWM storage tank in the CWM storage tank and is rotatable about the central shaft as a rotation center. One or a plurality of downcomers having a lower end located near the bottom of the CWM storage tank, which is connected to a liquid branch pipe, and the liquid branch pipe and the downpipe are rotated about the central axis as a rotation center. A rotating mechanism for
An ejection pipe, which is horizontally provided in a lower end portion of the downcomer pipe in a direction orthogonal to a traveling direction of the downcomer pipe and has an ejection port for ejecting CWM in a direction orthogonal to the traveling direction of the downcomer pipe,
C for collecting the CWM in the CWM storage tank, which is arranged outside the CWM storage tank, and supplying the recovered CWM to the ejection pipe via the liquid delivery branch pipe and the downcomer pipe.
In a coal particle deposition prevention device for a CWM storage tank comprising a WM circulation mechanism, the downcomer pipe is connected to the liquid delivery branch pipe via a joint capable of angular displacement, and the liquid delivery branch pipe is connected by the joint. The angle of the downcomer with respect to is variable, the coal particle deposition prevention device for a CWM storage tank.