JPH0958785A - Method and device for preventing accumulation of cwm in storage tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent CWM(cool/water mixture) from accumulating in a CWM storage tank by a method wherein a blowoff pipe which is provided at the end of a down pipe and located near the bottom of the CWM storage tank is turned about the down pipe which moves, while it sucks up CWM liquid stored in the tank to blow off the liquid thereby to agitate it. SOLUTION: A blowoff pipe 13 is connected to a down pipe 12 through a rotary joint 22 so as to be turned about the pipe 12. The pipe itself is turned about a rotary joint 10 by a travel device 18. By forming the blowoff pipe 13 into an S-shape to turn the pipe 13, stored liquid 15 which blows off can be utilized as a power source to turn the pipe 13. That is, when a liquid 15 is blown off from a blowoff port 20, the pipe 13 itself is turned about the joint 22 by the reaction force of the liquid 15. As a result, effects of blowoff of the liquid are provided below the pipe 13 and hence a dead space of agitation is eliminated, whereby CWM(cool/water mixture) is efficiently prevented from accumulating in a CWM storage tank 1.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a CWM (Coal
Water Mixture: A device for preventing coal particles from accumulating at the bottom of a storage tank for a mixture of fine coal and water.

[0002]

2. Description of the Related Art CWM is a liquid produced by adding water to coal and adding a small amount of an additive (surfactant) to a finely pulverized product to maintain a stable mixed state for a long time and is used as a fuel. ing. 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 (temperature 25 ° C., shear rate (At 100 (1 / 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 sediment layer is formed at the bottom of the storage tank. If left unattended, the accumulated layer will gradually increase, 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. In an actual CWM storage tank, there is also an example in which a deposit of 1 to 2 m is generated during the storage period of one year.

As a conventional technique for solving this,
There is a technique disclosed in Japanese Utility Model Publication No. 1-100795.

FIG. 3 shows an explanatory view of an embodiment of the apparatus.
A liquid delivery pipe 9 is vertically provided in the center of the CWM storage tank 1, and the liquid delivery branch pipe 11 and the downcomers 12, 12 are rotated by a traveling device 18 traveling along a rail 14 to form a rotary joint 10.
You can rotate around. A jet pipe 13 is provided at the lower end of each downcomer pipe 12 at a position close to the bottom plate 19 at the bottom of the CWM storage tank 1. The ejection pipe 13 is provided horizontally in a direction orthogonal to the traveling direction of the cylindrical downcomer 12, and the ejection ports 20 are provided at the ends 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 via the liquid suction pipe 2, the liquid feed pipes 4 and 9, the liquid feed branch pipe 11, the down pipes 12 and 12 by the circulation pump 3. Deposition C that is ejected from 20 in a direction orthogonal to the traveling direction of the downcomer 12, and is deposited on the bottom plate 19 by the ejected CWM
WM17 is stirred and removed.

[0006]

However, in the above apparatus, as shown in FIG. 4, the effect of preventing the deposition of the jet flow does not extend to the lower portion of the jet outlet, so that the CWM deposits at the lower portion of the jet outlet and the deposit grows. By doing so, there is a problem that the rotation of the ejection pipe about the central axis of the storage tank is hindered.

[0007]

[Means for Solving the Problems] The above problems are caused by the C in the storage tank.
A method of preventing CWM from accumulating in the CWM storage tank by absorbing the WM storage solution and agitating the storage solution by ejecting the WM storage solution from the ejection pipe provided at the tip of the moving downcomer and located near the bottom of the storage tank. CW characterized in that the stored liquid is jetted and agitated while the jet pipe is swung around the downcomer pipe as an axis.
It is solved by the method of preventing the accumulation of M storage tank.

[0008] Since the jetting pipe swirls around the moving down pipe to spout the stored liquid to stir it, the blind spot of stirring is eliminated, and the volume of the CWM can be effectively prevented.

According to this method, one or a plurality of movable downcomers having a lower end located at a position close to the bottom of the CWM storage tank and an ejection port for ejecting the CWM provided at the lower end of the downcomer are provided. Injecting the ejection pipe and the CWM in the CWM storage tank installed outside the CWM storage tank,
This can be realized by a deposition preventing device for a CWM storage tank, which has a CWM circulation mechanism for supplying the sucked CWM to the ejection pipe through the downcomer pipe.

Further, in this apparatus, the jet pipe is installed in the descending pipe portion of the CWM liquid feed pipe via the rotary joint, and the jet pipe is formed into a "~" shape, so that the jet pipe is Since the descending pipe is swung around the center of rotation by its own jet reaction force, the jet pipe can be swung without using a special drive device.

[0011]

1 shows an example of an embodiment of the present invention.

In FIG. 1, the same parts as those in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted. The jet pipe 13 is a rotary joint 2
It is connected to the downcomer pipe 12 via 2 and turns around the downcomer pipe 12 as an axis. The downcomer pipe 12 itself rotates around the rotary joint 10 by the traveling device 18. With this configuration, there is no blind spot in the portion agitated by the liquid storage 15, and the effect of the jet flow also extends to the lower portion of the ejection pipe 13, and the accumulation of CWM in that portion can be prevented.

As a method of rotating the jet pipe 13, a known method such as a method using a motor can be adopted.
As shown in FIG. 2, by forming the ejection pipe itself into a "-" shape, the ejected storage liquid 15 can be used as a power source for swirling. That is, FIG. 2 shows a view of the ejection pipe 13 and the ejection port 20 as seen from above, but in FIG. 2, the ejection pipe 13 has a “-” shape, so When the stored liquid 15 is ejected, the ejection pipe 13 is rotated about the rotation joint 22 provided on the downcomer pipe 12 by the reaction force thereof.

Therefore, the effect of the jet flow also extends to the lower portion of the jet pipe 13, and the accumulation of CWM in that portion can be prevented.

[0015]

EFFECTS OF THE INVENTION According to the present invention, since CWM deposits do not occur in the lower part of the ejection pipe, the device can be operated safely without hindering the rotation of the ejection pipe centering on the center of the storage tank.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of an embodiment of the present invention.

FIG. 2 is a diagram showing an example of an embodiment of an ejection pipe of the present invention.

FIG. 3 is a diagram showing an example of a conventional technique.

FIG. 4 is a diagram showing a problem in the conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CWM storage tank 2 Liquid absorption pipe 3 Circulation pump 4 Liquid supply pipe 9 Liquid supply pipe 10 Rotary joint 11 Liquid supply branch pipe 12 Downcomer pipe 13 Ejection pipe 14 Rail 15 Storage liquid (CWM) 17 Deposited CWM 18 Traveling device 19 Storage tank bottom plate 20 Spout 22 Rotating joint

Claims (3)

[Claims] 1. A CWM is stored in a CWM storage tank by absorbing the CWM storage liquid in the storage tank and ejecting it from an ejection pipe provided at the tip of a moving downcomer located near the bottom of the storage tank to stir the stored liquid. A method for preventing accumulation, wherein a stored liquid is jetted and agitated while the jet pipe is swung around a downcomer pipe as an axis, to prevent deposition in a CWM storage tank. 2. A spout having one or a plurality of movable downcomers having a lower end located in the vicinity of the bottom of the CWM storage tank and an ejection port for ejecting CWM provided at the lower end of the downcomer. The pipe and the CWM in the CWM storage tank installed outside the CWM storage tank are inhaled, and the inhaled C
In a deposition preventing device for a CWM storage tank, which comprises a CWM circulation mechanism for supplying WM to the ejection pipe via the downcomer pipe, the ejection pipe provided at the lower end of the downcomer pipe is swirled. CWM storage accumulation prevention device. 3. The CWM storage tank according to claim 2, wherein a jetting pipe is installed in the descending pipe portion of the CWM liquid sending pipe via a rotary joint, and the jetting pipe has a “-” shape. Accumulation prevention device.