JPH0892576A - Production of cwp and apparatus therefor - Google Patents

Abstract

PURPOSE: To obtain a coal-water paste(CWP) having high fluidity. CONSTITUTION: In producing this CWP with 70-85wt.% coal concentration and 1.0-1.5mm average coal granular diameter, part of crushed coal with 85-99wt.% content of coal <=3mm in granular diameter is wet-ground to form a CWP with 50-65wt.% coal concentration, which is then blended with the rest of the crushed coal, followed by kneading to afford the objective CWP with 20-30wt.% content of fine coal particles <=50μm in diameter.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a CWP (Coal) used as a fuel for a pressurized fluidized bed boiler combined cycle power plant.
Water Paste: Coal / water paste manufacturing method and apparatus.

[0002]

2. Description of the Related Art CWP is a paste-like fluid in which coal particles and water are mixed, and its typical properties are a maximum particle size of 10 mm, an average particle size of 1.0 to 1.5 mm, and a coal concentration of 7 mm.
0-85% by weight, viscosity 10,000 mPa · S (at2
5 ° C., 100 sec ⁻¹ , down). Conventionally, in this type of CWP, a part of the pulverized coal required for the production of CWP (for example, 60 to 90% by weight of the total pulverized coal) is stirred by the first stage stirring means together with the total amount of water required for the production. CWP, and then the remaining crushed carbon is added to this CWP and stirred by the second-stage stirring means (see JP-A-6-108067), or the crushed carbon is divided by batch operation. It is manufactured by supplying crushed charcoal at the next stirring and mixing stage when the amount of change in the torque detection value of the mixture becomes saturated at each stirring and mixing stage of batch operation. See Kaihei 6-108068).

[0003]

However, in the conventional method for manufacturing CWP, a coarse crusher such as a roll crusher or a hammer crusher and a coarse grain separator such as a vibrating screen are used.
Since the average particle size is 1 to 2 mm by dry crushing, and coarse particles having a maximum diameter of 6 mm or more are separated and removed to obtain a crushed carbon whose particle size is adjusted, it becomes difficult to include many fine particles of 50 μm or less in CWP. , High fluidity CW
There is a problem that P cannot be obtained. Therefore, it is an object of the present invention to provide a method for producing CWP and an apparatus therefor that can obtain high fluidity.

[0004]

In order to solve the above-mentioned problems, the first method for producing CWP of the present invention has a coal concentration of 70%.
~ 85 wt%, CW with an average coal particle size of 1.0 to 1.5 mm
When producing P, the grain size is 3 mm or less 85-99% by weight
After crushing a part of the crushed coal of No. 2 to CWP having a coal concentration of 50 to 60% by weight, the remaining crushed coal is added to this CWP and kneaded. The second method for producing CWP is the same as the first method, except that the crushed coal is preliminarily reduced to 10
It is characterized in that coarse particles of mm or more are separated and removed. A part of the crushed coal is preferably 15 to 30% by weight of the total crushed coal. On the other hand, the first CWP of the present invention
Is a CWP manufacturing apparatus having a coal concentration of 70 to 85% by weight and a coal average particle size of 1.0 to 1.5 mm, and crushing a part of crushed coal having a particle size of 3 mm or less and 85 to 99% by weight together with water. A wet pulverizer for preparing CWP having a coal concentration of 50 to 65% by weight and a kneader for kneading by adding the remaining crushed coal to the CWP discharged from the pulverizer. The second CWP manufacturing apparatus is characterized in that, in the first apparatus, a coarse particle separator for separating and removing coarse particles of 10 mm or more in advance from the crushed coal is provided. A part of the crushed coal is preferably 15 to 30% by weight of the total crushed coal. The wet crusher is preferably a wet ball mill.

[0005]

In the first CWP manufacturing method and apparatus according to the present invention, it is possible to add 20 to 30% by weight of coal fine particles having a size of 50 μm or less. Further, in the second CWP manufacturing method and apparatus, in addition to the function of the first one, it becomes possible to remove coarse particles of 10 mm or more.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing an embodiment of the CWP manufacturing apparatus of the present invention. In the figure, 1 is a crusher such as an impact crusher or a roll crusher.
Raw coal supplied from a raw coal bunker by a raw coal dispenser (both not shown) is crushed to obtain crushed coal having a particle size of 3 mm or less and 85 to 99% by weight. The crushed coal is supplied by a conveyor 2 to a coarse particle separator 3 such as a vibrating screen, and after the coarse particles of 10 mm or more are separated and removed, the crushed coal is stored in a crushed coal hopper 5 by the conveyor 4 while the coarse particles of 10 mm or more are stored. Are returned to the crusher 1 by the conveyor 6 and crushed again. Part of the crushed coal stored in the crushed coal hopper 5, that is, 15 to 30 of all the crushed coal necessary for manufacturing the required CWP.
The weight% is supplied to a wet pulverizer 10 composed of a wet ball mill by a first fixed amount feeder 7, a conveyor 8 and a screw feeder 9, and a wet pulverizer is passed from a water tank 11 through a pipe line 13 having a flow rate control valve 12 interposed. Wet-milled with water supplied to No. 10 and less than 50 μm and about 60 wt% C
The particle size is adjusted to WP. In this case, the ratio of crushed coal and water supplied to the wet crusher 10 is set so that the coal concentration is 50 to 60% by weight.

The CWP discharged from the wet crusher 10 is
From the crushed coal hopper 5 to the second fixed amount feeder 14 and the conveyor 1
5, the remaining crushed coal supplied from No. 5 and limestone as a desulfurizing agent supplied from the limestone bunker 16 from the limestone bunker 16 are put into a kneading machine 18 such as a line mixer and kneaded to obtain a coal concentration of 70 to 85. CWP of about weight%
Becomes The CWP discharged from the kneading machine 18 is divided into the branch line 2 which is branched from the line 13 through the flow rate control valve 19.
CWP tank 21 with the required amount of water supplied by
And is stirred by the stirring blade 22 to obtain a coal concentration of 70 to 85% by weight and a coal average particle size of 1.0 to 1.5.
mm, coal fine particles 50 μm or less 20 to 30% by weight, viscosity 10,000 mPa · S (at 25 ° C., 100 se)
c ^-1 , down) desired CWP and stored.
The CWP is supplied to the pressurized fluidized bed boiler by a CWP pump (not shown) and burned.

[0008] Here, when CWP was produced from the above-mentioned production apparatus (Example 1), the apparatus from which the coarse particle remover was removed (Example 2), and the raw coal having the same properties according to the conventional example, the average particle size, The cumulative weight ratio of 50 μm or less, viscosity, and coal concentration were as shown in Table 1.

[0009]

[Table 1]

From Table 1, the CWP manufacturing method and apparatus according to the present invention can increase the amount of coal fine particles of 50 μm or less by 10 to 20% by weight as compared with the conventional example, and obtains high fluidity at the same coal concentration. On the other hand, in the case of the same fluidity, it can be seen that a high coal concentration can be achieved.

[0011]

As described above, the first C of the present invention is used.
According to the WP manufacturing method and the apparatus thereof, it is possible to contain 20 to 30% by weight of coal fine particles having a size of 50 μm or less.
The amount can be increased by 0 to 20% by weight, and in the case of the same coal concentration, CWP having high fluidity can be obtained. Further, according to the second CWP manufacturing method and the apparatus thereof, in addition to the function and effect of the first one, coarse particles of 10 mm or more can be removed. Obtainable.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of a CWP manufacturing apparatus of the present invention.

[Explanation of symbols]

 3 Coarse Particle Separator 5 Crushed Coal Hopper 7 1st Constant Feeder 10 Wet Crusher 11 Water Tank 18 Kneader 21 CWP Tank

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[Procedure amendment]

[Submission date] November 28, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

[0004]

In order to solve the above-mentioned problems, the first method for producing CWP of the present invention has a coal concentration of 70%.
~ 85 wt%, CW with an average coal particle size of 1.0 to 1.5 mm
When producing P, the grain size is 3 mm or less 85-99% by weight
After the CWP part of wet milled coal concentration 50-6 5% by weight of crushed charcoal, characterized by kneading by adding remaining crushed coal to the CWP. The second method for producing CWP is the same as the first method, except that the crushed coal is preliminarily reduced to 10
It is characterized in that coarse particles of mm or more are separated and removed. A part of the crushed coal is preferably 15 to 30% by weight of the total crushed coal. On the other hand, the first CWP of the present invention
Is a CWP manufacturing apparatus having a coal concentration of 70 to 85% by weight and a coal average particle size of 1.0 to 1.5 mm, and a part of the crushed coal having a particle size of 3 mm or less and 85 to 99% by weight is crushed together with water. A wet pulverizer for preparing a CWP having a coal concentration of 50 to 65% by weight and a kneader for kneading by adding the remaining crushed coal to the CWP discharged from the pulverizer. Further, the second CWP manufacturing apparatus is characterized in that, in the first apparatus, it is provided with a coarse particle separator for separating and removing coarse particles of 10 mm or more in advance from the crushed coal. A part of the crushed coal is preferably 15 to 30% by weight of the total crushed coal. The wet crusher is preferably a wet ball mill.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing an embodiment of the CWP manufacturing apparatus of the present invention. In the figure, 1 is a crusher such as an impact crusher or a roll crusher.
Raw coal supplied from a raw coal bunker by a raw coal dispenser (both not shown) is crushed to obtain crushed coal having a particle size of 3 mm or less and 85 to 99% by weight. The crushed coal is supplied by a conveyor 2 to a coarse particle separator 3 such as a vibrating screen, and after the coarse particles of 10 mm or more are separated and removed, the crushed coal is stored in a crushed coal hopper 5 by the conveyor 4 while the coarse particles of 10 mm or more are stored. Are returned to the crusher 1 by the conveyor 6 and crushed again. Part of the crushed coal stored in the crushed coal hopper 5, that is, 15 to 30 of all the crushed coal necessary for manufacturing the required CWP.
The weight% is supplied to a wet pulverizer 10 composed of a wet ball mill by a first fixed amount feeder 7, a conveyor 8 and a screw feeder 9, and a wet pulverizer is passed from a water tank 11 through a pipe line 13 having a flow rate control valve 12 interposed. Wet-milled with water supplied to No. 10 and less than 50 μm and about 60 wt% C
The particle size is adjusted to WP. In this case, the proportion of crushed coal and water supplied to the wet pulverizer 10 is made to be a coal concentration 50-6 5 wt%.

Claims (7)

[Claims] 1. When producing a CWP having a coal concentration of 70 to 85% by weight and an average coal particle size of 1.0 to 1.5 mm, a portion of crushed coal having a particle size of 3 mm or less and 85 to 99% by weight is wet pulverized to obtain coal. A method for producing CWP, which comprises forming a CWP having a concentration of 50 to 65% by weight and then adding the remaining crushed coal to the CWP and kneading. 2. The method for producing CWP according to claim 1, wherein coarse particles of 10 mm or more are separated and removed from the crushed coal in advance. 3. A part of the crushed coal is 15 to 15% of the total crushed coal.
It is 30% by weight, and the method for producing CWP according to claim 1 or 2. 4. A CWP manufacturing apparatus having a coal concentration of 70 to 85% by weight and a coal average particle size of 1.0 to 1.5 mm, wherein a part of the crushed coal having a particle size of 3 mm or less and 85 to 99% by weight is ground together with water. A wet pulverizer for preparing a CWP having a coal concentration of 50 to 65% by weight and a kneader for kneading by adding the remaining crushed coal to the CWP discharged from the pulverizer, and manufacturing the CWP. apparatus. 5. The CWP manufacturing apparatus according to claim 4, further comprising a coarse particle separator that separates and removes coarse particles of 10 mm or more from the crushed coal in advance. 6. A part of the crushed coal is 15 to 15% of the total crushed coal.
The CWP manufacturing apparatus according to claim 4 or 5, wherein the content is 30% by weight. 7. The CWP manufacturing apparatus according to claim 4, wherein the wet crusher is a wet ball mill.