JPS6119694A - Production of coal/water slurry having high coal content - Google Patents

Abstract

PURPOSE:To produce efficiently a coal/water slurry which is of good quality and has a high coal content, by separating a coarse particle-contg. slurry from a slurry having a low coal content obtd. by crushing coal in a wet process and returning it to a wet-process mill in the production of a coal/water slurry by a low-concentration wet process. CONSTITUTION:(i) Coal from a line 1 and water from a line 2 are fed to a wet- process mill 3 where coal is crushed. The resulting low-concentration slurry (coal content: 20-60wt%) is diluted (coal content: 15-40wt%) in a diluting tank 5 and then classified in a classifier 8. (ii) The resulting coarse particle-contg. slurry is returned through a line 9 to the wet-process mill 3 where the coarse particles are again crushed. The coarse particle-cut slurry is fed to a dehydrator 11. (iii) The dehydrated cake is fed to an agitator 14 where adjusting water from a line 15 and additives from a line 16 are mixed with the cake to form a high-concentration slurry having a low viscosity. The slurry is then drawn out from a line 17.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a highly concentrated coal water slurry with good slurry properties.

Coal high concentration water slurry (hereinafter referred to as high concentration slurry)
means 60-90% by weight of finely ground coal and 40-10% by weight of water.
It is a fluid fuel that is a mixture of heavy weight and some additives, and can be burned as is in a boiler etc. without dehydration.By converting coal, which is a solid fuel, into a fluid, the range of its uses can be dramatically expanded. It is something that expands.

Conventionally, there are eight types of methods for producing high concentration slurry: dry method, high concentration wet method, and low concentration wet method.

The dry method uses a mill to pulverize lime in the air and then
This is mixed and stirred with water and additives to form a highly concentrated slurry.

In addition, the high concentration wet method uses coal in a tube mill.

Water and additives are added at the same time, and pulverization, mixing, and stirring are performed at the same time.

Furthermore, in the low concentration wet method, coal and water are put into a tube mill and pulverized at a low concentration to form a coal low concentration water slurry, which is then dehydrated in a dehydrator to form a dehydrated cake, which is then transferred to a stirring tank. In this step, a small amount of water and an additive are again mixed and stirred to form a highly concentrated slurry.

The present invention overcomes the drawbacks of the conventional method of making a highly concentrated slurry using this one-component wet method.

What is illustrated in FIG. 1 is a flow sheet relating to a conventional method for producing a high concentration slurry using a low concentration wet method.

In Figure 1, a is a coal supply line, b is a water supply line, C is a wet mill, and d is a coal-concentrated water slurry (hereinafter referred to as low The dehydrator (e) is a dehydrator that dehydrates the low-concentration slurry to form a dehydrated cake. f is a dehydration circulation line for recirculating the water obtained by dehydration in the dehydrator e to the supply line a.

Coal and water are supplied to the mill C from respective supply lines a and b, and a low concentration slurry of 20 to 60% by weight is produced in the pulverization process 17. This low concentration slurry is dehydrated by a low concentration slurry transport line d. Supply to machine e. Dehydrator e
Then, the low concentration slurry is dehydrated, the dehydrated water is recirculated to the water supply line b via the dehydration circulation line f, and the dehydrated slurry is transferred to the dehydrated cake coal import line g as a dehydrated cake.
The mixture is fed to the mixer via the agitator. In this mixer, the supplied dehydrated cake is mixed and stirred with water and additives supplied from the water supply line i and the additive supply line j to prepare a high concentration slurry with low viscosity. The slurry is transported from the slurry transport line k to a boiler combustion means (not shown) or the like.

In the production process shown in FIG. 1, two coals are crushed in water at a low concentration, so only a small amount of ultrafine coal particles are produced.

Since only a small amount of ultrafine coal particles are contained in the finished highly concentrated slurry, the rheological properties of the highly concentrated slurry are dilatant and the storage stability is poor.

On the other hand, since the finished high-concentration slurry contains a large amount of coarse particles, the high-concentration slurry prepared by the conventional low-concentration wet method high-concentration slurry manufacturing method is combusted using a combustion means such as a boiler (not shown). However, there were eight drawbacks: a large amount of unburned carbon, a large amount of residue in the boiler, and poor combustion efficiency.

Based on these findings, the present invention aims to eliminate the drawbacks of the conventional low-concentration wet high-concentration slurry production methods described above, and to provide a high-quality high-concentration water slurry with good storage stability and high combustion efficiency. That is.

That is, the first invention of the present invention is to prepare a low-concentration slurry by wet-pulverizing 7 coal in water using a wet mill, and then diluting the low-concentration slurry with water, and then using a classifier to prepare a low-concentration slurry containing coarse particles. Slurry (hereinafter referred to as low concentration slurry containing coarse particles) and low concentration slurry from which coarse particles have been removed (hereinafter referred to as low concentration slurry containing coarse particles).

This is referred to as coarse-grained, low-concentration slurry. ) Classified into ゛.

The coarse particle-containing resistance slurry is returned to the wet mill for recirculation, while the coarse particle low concentration slurry is dehydrated to form a dehydrated cake (hereinafter referred to as coarse cut dehydrated cake). This is a method for producing a highly concentrated slurry, which is characterized by introducing a cake into a mixer, supplying water and additives, and mixing and stirring to prepare a highly concentrated slurry.

Hereinafter, two preferred embodiments of the first aspect of the present invention will be described in detail with reference to the embodiments illustrated in FIGS. 2 to 4.

The embodiment illustrated in FIG. 2 is a flow sheet of the first embodiment according to the first invention of the present invention.

In Figure 2, 1 is a coal supply line, 2 is a water supply line, 3 is a wet mill, and 4 is transportation of a low-concentration slurry with a coal content of 20 to 60% by weight obtained in a wet Mi/I/8 process. line, 5 is a dilution tank that dilutes the supplied low concentration slurry to a concentration that is easy to classify with dilution water supplied from dilution water supply line 6; A line 8 for supplying concentrated slurry (hereinafter referred to as diluted low concentration slurry) separates coarse grains in the supplied diluted low concentration slurry to produce coarse grain-containing diluted low concentration slurry and coarse grain cut diluted low concentration slurry. 9 is a return circulation line for the diluted resistance slurry containing coarse particles for wet milling the coarse particles classified by the classifier 8 again in the wet mill 3; 10 is a return circulation line for the coarse particles classified by the classifier 8; The transportation line ν11 for the coarse grain cut diluted low concentration slurry is a dehydrator.
The dehydration 11 is to dehydrate the coarse grain cut diluted low concentration slurry to form a dehydrated cake. 12 is a drainage line for dehydrated water obtained by dehydration in the dehydrator, and 13 is the coarse grain power obtained in the dehydrator 11.

14 is a dehydrated cake transport line; 14 is a mixing agitator;

15 and 16 are supply lines for adjusting water and additives such as surfactants, which are supplied to prepare a highly concentrated slurry; 17 is a coarse cut dehydrated cake using a mixing agitator 14;
This is a transportation line for highly concentrated slurry obtained by mixing and stirring adjustment water and additives.

In the embodiment configured as described above, coal and water are supplied to the wet mill 3 from the coal supply line 1 and the water supply line 2, and are wet-pulverized to produce a low-concentration slurry containing 9 coals and 20 to 60 parts by weight. make. This low concentration slurry is led to a dilution tank 5, where it is diluted with dilution water supplied from a dilution water supply line 6 to a concentration that is easy to classify, that is, 15 to 40% by weight of coal.

Next, this diluted low concentration slurry is supplied to the classifier 8 from the diluted low concentration slurry transport line 7.

The slurry is classified into coarse grain-containing diluted 1-component slurry and coarse grain cut diluted low concentration slurry. The diluted low-concentration slurry containing coarse particles is returned to the wet mill 8 via the return circulation line 9 of the diluted low-concentration slurry containing coarse particles. crushed into On the other hand, the coarse grain cut diluted low-concentration slurry obtained in the first classifier 8 is supplied to a dehydrator 11 from a transport line 10.

The dehydrator 11 dehydrates the coarse grain cut diluted low concentration slurry, and the dehydrated water is discharged from the dehydrated water discharge line 12.
Dehydrated cake is coarse grain cuff) Transport line 1 as dehydrated cake
3 is supplied to the mixing agitator 14. The mixer 14 mixes and stirs the supplied coarse-grain cut dehydrated cake with the conditioning water and additives supplied from the conditioning water supply line 15 and the additive supply line 16 to form a high-viscosity powder with a low viscosity. The concentrated slurry is adjusted and transported from the highly concentrated slurry transport line 17 to a combustion means such as a boiler or a storage tank (not shown).

FIG. 8 is a flow sheet of the second embodiment according to the first invention. The second embodiment shown in FIG. 3 is different from the first embodiment shown in FIG. A dehydrated water storage tank 18 for storing the obtained dehydrated water is provided, and a dehydrated water circulation line 19 is further added to connect the dehydrated water storage tank 18 and the water supply line 2. Note that 20 is a line for replenishing water in the dehydrated water storage tank 18 when water becomes insufficient.

The dehydrated water obtained by the dehydrator 11 is stored in a temporary dehydrated water storage tank 18 via a line 12, and the required amount is supplied to the wet mill 3 from a dehydrated water circulation line 19 via a water supply line 2.

In this way, in the second embodiment, by returning the dehydrated water to the water supply line 2, the supply of water from outside the yarn is reduced as much as possible.

FIG. 4 is a flow sheet of the third embodiment according to the first invention, in which the dehydrated water circulation line 19 and the dilution water supply line 6 are connected in the second embodiment illustrated in FIG. Therefore, by reusing a part of the dehydrated water obtained in the dehydrator 11 to the dilution tank 5, the water supply from outside the system can be further reduced. The aim was to reduce costs by eliminating the supply tank.

FIG. 5 is a flowchart of the fourth embodiment according to the first invention -1-
In addition, a branch supply line 21 for dehydrated water is added to the third embodiment shown in FIG. be. Then, a part of the dehydrated water obtained in the dehydrator 11 is supplied from the dehydrated water storage tank 18 to the adjustment water supply line 15 that is supplied to the mixing agitator 14 through the dehydrated water branch supply line 21. The aim is to further reduce the amount of water supplied from outside, and to omit the supply tank for adjusting water to be supplied to the mixer agitator 14, thereby further reducing costs.

As described above in detail based on the flow sheets of FIGS. 2 to 4 showing the embodiments of the first invention, the second invention involves wet-pulverizing lime in water using a wet mill to prepare a low-concentration slurry. After diluting the low concentration slurry with water, it is classified by a classifier into a low concentration slurry containing coarse particles and a low concentration slurry containing coarse particles, and the low concentration slurry containing coarse particles is returned to the wet mill for recirculation.

On the other hand, the above-mentioned coarse-grained, low-concentration three is dehydrated to make a coarse-grain cut dehydrated cake, and the coarse-grained and dehydrated cake is led to a mixing stirrer, and water for adjustment and additives are supplied, mixed and stirred to achieve a high concentration. Since slurry is obtained, the following effects can be obtained.

1) In a wet mill, pulverization is carried out at a low concentration (20 to 60% by weight of coal), which minimizes the pulverizing power.

It is possible to operate at the point where the crushing power is minimum.

2) Since the low concentration slurry containing coarse particles is re-pulverized using a wet mill, there are very few coarse particles in the high concentration slurry, and the fine coal particles increase, making the rheological properties of the high concentration slurry pseudoplastic and storage. Improved stability.

3) Since the coarse particles are classified using a classifier and the low concentration slurry containing coarse particles is crushed again using a wet grinder, the maximum diameter of the coarse particles in the high concentration slurry can be arbitrarily selected. Therefore, it becomes easy to obtain a highly concentrated slurry with a desired particle size distribution.

4) Since the slurry is classified using a classifier and the low concentration slurry containing coarse particles is ground again using a wet grinder, the amount of coarse particles in the high concentration slurry is extremely reduced. Therefore, when it is combusted by combustion means such as a boiler.

The amount of unburned carbon is extremely reduced, there is almost no residue in the boiler, and the combustion efficiency is improved.

5) Also, before classification with the classifier 1, the low concentration slurry of 20 to 60 parts by weight of coal is diluted to make a thin low concentration slurry of 15 to 40 parts by weight of coal.

The classification efficiency of the classifier is improved, making it possible to mass-produce high-concentration slurry products.

Next, the second invention of the present invention is provided in order to solve the problems of the first invention as described below and to obtain a high-density nullary of better quality. .

That is, in the production according to the flows illustrated in FIGS. 2 to 5, the coarse cut dehydrated cake supplied to the mixer 14 via the dehydrated cake transport line 13 is plate-shaped or in large chunks. When adjusting water for adjustment and additives were mixed and stirred all at once to form a slurry again to prepare a high-concentration nurary with low viscosity, it was difficult to atomize the slurry. Therefore, in order to obtain uniform mixing, it is necessary to operate the mixer agitator 14 for a long time, which increases the power cost, and the productivity per unit time to obtain a high-quality, high-concentration slurry is poor.

The purpose of the present invention is to eliminate the drawbacks of the low-concentration wet method high-concentration slurry production method in the first invention, and to produce high-quality high-concentration slurry at a low cost and with a high productivity per unit time. It was submitted as.

In other words, the second aspect of the present invention is to wet-pulverize coal in water to prepare a low-concentration slurry, dilute the low-concentration water slurry with water, and then use a classifier to form a low-concentration slurry containing coarse particles. The coarse grain cuff) is classified into low concentration slurry and the coarse grain-containing low concentration slurry is recycled to the wet mill.

On the other hand, the above-mentioned coarse grain force 7) low concentration slurry is dehydrated to form a coarse cut dehydrated cake, and the coarse cut dehydrated cake is crushed by a crusher and then guided to a mixing agitator and supplied with water for adjustment and additives. This is a method for producing a high concentration water nullary, which is characterized by mixing and stirring to prepare a high concentration water nullary.
1 Below 2 Preferred embodiments of the second invention of the present invention will be described in detail with reference to the embodiments illustrated in FIGS. 6 to 9.

The embodiments illustrated in FIG. 6, FIG. 7, FIG. 8, and FIG. 9 are flow sheets of the first embodiment, the second embodiment, the eighth embodiment, and the fourth embodiment according to the second invention of the present invention. It is.

In the embodiments shown in FIGS. 5, 6, 8 and 9, reference numerals 1 to 21 refer to FIG.

Since they are equivalent to the reference numerals 1 to 21 in the embodiments shown in FIGS. 3, 4, and 5, their explanation will be omitted. Further, 22 is a crushing device, and 23 is a transportation line for the small block frame-shaped dehydrated cake crushed by the crushing device 22.

In a flow sheet as shown in FIG. 5, coal and water are supplied from respective supply lines 1 and 2 to the wet mill 3 and pulverized to a low concentration to form a low concentration slurry of 85 to 60 parts by weight of coal.

This low concentration slurry is led to a dilution tank 7.

In this dilution tank 7, the dilution water supplied from the dilution water supply line 6 reaches a concentration that is easy to classify, that is, Ishiji 25 to 4.
Dilute to zero weight. Next.

This diluted resistivity nurary is supplied from the diluted resistivity nullary transport line 7 to a classifier 8, and is classified into coarse grain-containing diluted low concentration slurry and coarse grain cut diluted low concentration slurry. The diluted low concentration slurry containing coarse particles is returned to the wet mill 3 via the return circulation line 9 for the diluted low concentration slurry containing coarse particles,
The contained coarse particles are further pulverized in a wet mill 8 into pulverized coal or super-granular coal. On the other hand, the coarse grain cut diluted low concentration slurry obtained in the classifier 8 is supplied to a dehydrator 11 from a transport line 10. The dehydrator 11 dehydrates the coarse grain cut diluted low concentration slurry.

The dehydrated water is discharged from a dehydrated water discharge line 12, and the dehydrated cake is transported as a coarse cut dehydrated cake to a transportation line 13.
It is supplied to the agglomeration device 22 via.

This agglomeration device 22 agglomerates the supplied plate-shaped or block-shaped dehydrated cake into small or micro-agglomerates. This small lump-shaped cake or micro lump-shaped dehydrated cake (hereinafter referred to as small lump frame-shaped dehydrated cake) is transported to the transportation line 2 of small lump frame-shaped dehydrated cake.
3 to a mixer agitator 14. Mixer agitator 1
In step 4, the supplied small block frame-shaped dehydrated cake is mixed and stirred with the conditioning water and additives supplied from the conditioning water supply line 15 and the additive supply line 16 to form a high concentration slurry with low viscosity. The slurry is adjusted and transported from the high concentration slurry transport line 17 to a combustion means such as a boiler (not shown) or to a storage tank.

FIG. 7 is a flow sheet of a second embodiment according to the second invention. A dehydrated water storage tank 18 and a dehydrated water circulation line 19 are added to reduce the amount of water newly supplied to the water supply line 2, similar to the one shown in FIG.

FIG. 8 is a flow sheet of a third embodiment according to the second invention, in which the dehydrated water circulation line 19 and the dilution water supply line 6 are connected in the embodiment shown in FIG. By.

As in the case shown in FIG. 4, part of the dehydrated water obtained in the dehydrator 11 is reused in the dilution tank 5 to further reduce the supply of water from outside the system.

In addition, the water source for dilution was designed to be completely drained so as to omit the supply tank for dilution water.

FIG. 9 is a flow sheet of a fourth embodiment according to the second invention, which is similar to that shown in FIG. 5 by adding a branch supply line 21 for dehydrated water to the third embodiment shown in FIG. In addition to further reducing water supply from outside the system, mixing agitator 1
The aim was to eliminate the need for a supply tank for water for adjustment, which would be supplied to the fourth tank.

As described above in detail based on the flow sheets shown in FIGS. 6 to 9 which are embodiments of the second invention, the second invention of the present invention is as follows: The low concentration slurry is adjusted, and then the above low concentration slurry is diluted with water, and then classified into a coarse particle-containing resistance slurry and a coarse particle cut low concentration slurry using a classifier. It is returned to the wet mill and recirculated, while the low-concentration nurary is dehydrated to form a coarse cut dehydrated cake, and after the coarse cut dehydrated cake is crushed in a crusher, it is introduced into a mixing agitator for adjustment. Since water and additives are supplied and mixed and stirred to obtain a highly concentrated slurry, the following effects can be obtained in addition to the above-mentioned effects obtained in the first invention.

1) In order to supply the dehydrated cake to the mixing agitator by crushing it into small rings, the water for adjusting the nullary and the additives supplied to the mixing agitator can be uniformly mixed and agitated, resulting in good quality and uniformity. A highly concentrated slurry can be obtained.

2) Also, uniform mixing can be done smoothly.

The amount of highly concentrated slurry produced per unit time is significantly increased, and therefore productivity is improved.

Next, the third invention of the two inventions is a further improvement of the second invention.

That is, the third aspect of the present invention is to wet-pulverize coal in water using a wet mill to prepare a low-concentration water slurry, then dilute the low-concentration slurry with water, and then use a classifier to prepare a low-concentration slurry containing coarse particles. Separated into slurry and coarse cut low concentration slurry.

The coarse grain-containing low concentration slurry is returned to the wet mill and recirculated, while the coarse cut low concentration slurry is dehydrated to form a coarse cut dehydrated cake, and the coarse cut dehydrated cake is agglomerated using a torque equalization type agglomeration device. This is a method for producing a high-concentration slurry, which is characterized in that after crushing, the slurry is introduced into a mixing agitator, and water for adjustment and additives are supplied, and the slurry is mixed and agitated to adjust a high-concentration slurry.

Hereinafter, preferred embodiments of the eighth aspect of the present invention will be described in detail with reference to the embodiments illustrated in FIGS. 10 to 13.

The embodiments illustrated in FIG. 10, FIG. 11, FIG. 12, and FIG. 13 are flow sheets of the first embodiment, second embodiment, third embodiment, and fourth embodiment according to the third invention of the present invention. It is.

In the embodiments illustrated in FIGS. 10, 11, 12, and 13, reference numerals 1 to 21 refer to FIG.

Since they are equivalent to the reference numerals 1 to 21 in the embodiments shown in FIGS. 3, 4, and 5, their explanation will be omitted. And 24 is a torque equalization type crushing device.

25 is a transport line for the small crushed dehydrated cake crushed by the torque equalization type crushing device 24.

FIG. 14 is a perspective partial view of the torque equalization type crushing device applied to each of the above embodiments. In Figure 14, 24
a is the inlet of the dehydrated cake, 24b is the outlet of the small crushed dehydrated cake, 24C is a group of wedge-shaped nurisoto rods installed in parallel with appropriate intervals and tapers toward the upper end, and 24d is the slit 7. ) A rotating shaft disposed substantially perpendicular to the longitudinal direction of the monthly salary group 240, 24e is a motor that rotates the rotating shaft 24d,
Reference numeral 24f denotes a group of agglomerate crushing rods which are provided out of phase when viewed in the circumferential direction of the rotating shaft 24d, and which are fitted so as to engage with each of the slots 7) made by the slits 240. be.

In a flow sheet as shown in FIG. 10, coal and water are supplied from respective supply lines 1 and 2 to a wet mill 3 and pulverized at a low concentration to form a low concentration slurry of 35 to 60% by weight. This low concentration slurry is transferred to dilution tank 7.
In this dilution tank 7, the coal is diluted with dilution water supplied from the dilution water supply line 6 to a concentration that is easy to classify, that is, 15 to 40% by weight of coal. Next, this diluted resistance slurry is supplied from the diluted low concentration slurry transport line 7 to the classification 8 and is classified into a coarse particle-containing diluted low concentration slurry and a coarse particle cut diluted low concentration slurry. The diluted low concentration slurry containing coarse particles is returned to the wet mill 3 via the return circulation line 9 for the diluted low concentration slurry containing coarse particles, and the contained coarse particles are further pulverized into pulverized coal or ultrafine coal in the wet mill 3. be done. On the other hand, the coarse grain cut diluted low-concentration nullary obtained in the classifier 8 is supplied to a dehydrator 11 from a transport line 10. The dehydrator 11 dehydrates the coarse cut diluted low-concentration slurry, the dehydrated water is discharged from the dehydrated water discharge line 12, and the dehydrated cake is transported as a coarse cut dehydrated cake through the transport line 13 to Torrek evenly. It is supplied to the mold crushing device 24. This torque-equalized crushing device 24 crushes the supplied plate-shaped or block-shaped dehydrated cake.

This dehydrated cake in the form of crushed small pieces is supplied to the mixer agitator 14 via a transport line 25. The mixing agitator 14 mixes and stirs the supplied small-sized crushed dehydrated cake with the conditioning water and additives supplied from the conditioning water supply line 15 and the additive supply line 16 to form a high concentration with low viscosity. The high concentration slurry is adjusted by adjusting the nullary and is transported from the high concentration slurry transport line 17 to a combustion means such as a boiler or a storage tank (not shown).

FIG. 11 is a flow sheet of the second embodiment according to the third invention, in which a water supply source to the water supply line 2 not shown in the first embodiment shown in FIG. A water storage tank 18 and a dehydrated water circulation line 19 are added to reduce the amount of water newly supplied to the water supply line 2, similar to the one shown in FIG.

FIG. 12 is a flow sheet of the eighth embodiment according to the third invention, and in the third embodiment illustrated in FIG. 11, the dehydrated water circulation line 19. and a dilution water supply line 6, whereby a portion of the dehydrated water obtained from the dehydrator 11 is transferred to the dilution tank 5, similar to the one shown in FIG.
The aim is to further reduce the amount of water supplied from outside the system by reusing it, and to reduce costs by eliminating the dilution water source and the dilution water supply tank.

FIG. 13 is a flow sheet of a fourth embodiment according to the third invention, in which a branch supply line 21 for dehydrated water is added to the third embodiment shown in FIG. 12 to create a system similar to that shown in FIG. This aims at reducing costs by further reducing the supply of water from outside and by omitting the supply tank for adjusting water that is supplied to the mixer agitator 14.

As described above, FIGS. 10 to 18 which are embodiments according to the third invention
As described in detail based on the flow sheet illustrated in the figure, 1. The third invention of the present invention is to wet-pulverize coal in water using a wet mill to prepare a low-concentration slurry, and then dilute the low-concentration slurry with water. After that, the coarse grain-containing low-concentration slurry and the coarse-grain cut low-concentration slurry are classified in two classifiers, and the coarse grain-containing low-concentration slurry is returned to the wet mill for recirculation, while the coarse grain power, The concentrated slurry is dehydrated to form a coarse cut dehydrated cake, and the coarse cut dehydrated cake is crushed using a torque equalization type agglomeration device, and then introduced into a mixing agitator and supplied with conditioning water and additives to mix and agitate it. Since a concentrated slurry is obtained, the following effects can be obtained in addition to the above-mentioned effects obtained in the first and second inventions.

1) Since the agglomeration device is of a torque-equalizing type, the torque applied to the motor is uniform, preventing the motor from overheating, and the agglomeration work can be carried out smoothly with a small-capacity motor. Since the agglomeration process is carried out very smoothly in this way, a large amount of highly concentrated slurry can be produced smoothly.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a flow sheet of a conventional high concentration slurry manufacturing method using a low concentration wet method, FIGS. 2 to 5 are flow sheets of an embodiment according to the first invention of the present invention, and FIG. 9th to 9th
The figure is a flow sheet of an embodiment according to the second invention of the present invention,
FIGS. 10 to 13 are flow sheets of an embodiment according to the third aspect of the present invention, and FIG. 1...Coal supply line, 2...Water supply line. 3... Wet mill, 4... Low concentration slurry transport line, 5... Dilution tank, 6... Dilution water supply line. 7...Transport line for diluted low concentration slurry, 8...Classifier, 9...Return circulation line for low concentration slurry containing coarse particles, 10...Transport line for coarse particle power, diluted low concentration slurry , ii... Dehydrator, 12... Drainage line for dehydrated water, 13... Transportation line for coarse cut dehydrated cake. Work 4...Mixing agitator, 15...Adjustment water supply line. 16...Additive supply line, 17...High concentration slurry transport line, 18...Dehydrated water storage tank, 1
9... Dehydrated water circulation line, 20... Replenishment water supply line. 21... Branch supply line for dehydrated water, 22... Clumping device. 23... Transportation line for small block frame-shaped dehydrated cake, 24...
・Torque uniform type agglomeration device, 25...Transportation line for small agglomerated frame-shaped dehydrated cakes. Figure 1 Figure 20 Figure 6 Port 10

Claims (1)

[Claims] 1) Coal is wet-pulverized in water using a wet mill to prepare a low-concentration coal water slurry, and then the low-concentration coal water slurry is diluted with water and then passed through a classifier to contain coarse particles. The coal low concentration water slurry was classified into a low concentration coal water slurry and a low concentration coal water slurry from which coarse particles were removed, and the low concentration coal water slurry containing the coarse particles was returned to the wet mill for recirculation, while the coarse particles were removed. The coal low concentration water slurry is dehydrated to form a dehydrated cake.
A method for producing a high-concentration coal water slurry, which comprises introducing the dehydrated cake into a mixing agitator, supplying water and additives, and mixing and stirring to prepare a high-concentration coal water slurry. 2) Coal is wet-pulverized in water using a wet mill to prepare a coal low-concentration water slurry, and then the above-mentioned coal low-concentration water slurry is diluted with water, and then a coal low-concentration water slurry containing coarse particles is prepared using a classifier. The coal low concentration water slurry from which coarse particles have been removed is classified, and the coal low concentration water slurry containing coarse particles is returned to the wet mill for recirculation, while the coal low concentration water slurry from which coarse particles have been removed is Dehydrate to make dehydrated cake,
A method for producing a high-concentration coal water slurry, which comprises crushing the dehydrated cake using a crusher, then introducing it into a mixer and agitator, supplying water and additives, and mixing and stirring to prepare a high-concentration coal water slurry. 3) Coal is wet-pulverized in water using a wet mill to prepare a coal low-concentration water slurry, and then the above-mentioned coal low-concentration water slurry is diluted with water, and then a coal low-concentration water slurry containing coarse particles is prepared using a classifier. The coal low concentration water slurry from which coarse particles have been removed is classified, and the coal low concentration water slurry containing coarse particles is returned to the wet mill for recirculation, while the coal low concentration water slurry from which coarse particles have been removed is The dehydrated cake is dehydrated to form a dehydrated cake, and the dehydrated cake is crushed using a torque equalization type crushing device, and then introduced into a mixer and stirrer, and water and additives are supplied thereto and mixed and stirred to prepare a highly concentrated coal water slurry. Method for producing highly concentrated coal water slurry.