JP6551027B2 - Method for cooling rolls of coal agglomerator - Google Patents

Description

  The present invention relates to a method for cooling a roll of a coal agglomerator.

In the production of coke for iron making, a process of drying, classifying, and agglomerating coal is performed in advance. At that time, it is general to agglomerate coal using a double roll type agglomeration machine.
In recent years, there has been progress in increasing the dryness of coal and the application of technology using heavy tar-based binders in response to the demand for utilizing inexpensive coal, but all are in the direction of raising the coal temperature. Therefore, the coal temperature at the time of agglomeration tends to rise. When the temperature of the agglomerated coal rises, the coal tends to adhere to the roll surface of the coal agglomerator, resulting in a problem that the agglomerated yield is lowered.

In order to cope with the above-mentioned problems, measures for cooling coal compactor rolls and coal have been devised conventionally. For example, in Patent Document 1, coal adhesion to the surface of the mold becomes remarkable when the surface temperature of the mold approaches the binder softening point temperature, and cold air is blown to the surface of the mold as a method of cooling the surface of the mold. Or, it is described that cooling water is passed into the forming roll.
Patent Document 2 discloses a method of spraying mist water or water vapor onto the roll surface in order to improve the biting property of pulverized coal in a roll molding machine.

JP-A-57-151695 JP 2014-80523 A

However, in the case of the method described in Patent Document 1, since the method of blowing cold air on the molding mold surface is air cooling, the temperature reduction effect is not sufficient, and there is a possibility that the agglomeration yield may be lowered due to high temperature. In the case of water cooling as well as air cooling, cooling is insufficient in cooling only the roll portion (see the verification test described later).
On the other hand, according to the method described in Patent Document 2, the roll surface temperature can be reduced, but in order to obtain a sufficient cooling effect, it is necessary to spray a large amount of water on the roll surface, and the dried coal There is a concern to raise water content.

  The present invention has been made in view of such circumstances, and a method for stabilizing the agglomeration and maintaining the agglomeration yield at a high level by sufficiently reducing the temperature of the roll surface of the double roll coal agglomerator. The purpose is to provide.

  The roll of the coal agglomerator is heated by the calorie of the supplied coal or heat generated by the agglomeration load when agglomerating, and the surface temperature rises. When the surface temperature of the roll rises, coal adheres to the roll surface due to the influence of softening of the tar binder. If the adhesion of coal is remarkable, the agglomeration is hindered and the yield of the agglomerated coal decreases. Therefore, it is necessary to reduce the surface temperature of the roll for stable agglomeration.

The present invention has a large effect of heat generation in the bearing portion that supports the bearing portion of the roll as a factor that affects the roll surface temperature, and that the effect of cooling the bearing portion supported by the bearing portion is large. This is based on what the present inventors have found.
That is, the method for cooling a roll of a coal agglomerator according to the present invention is characterized in that the bearings at both ends of the roll of the double roll type coal agglomerator are cooled.

  In the method of cooling a roll of a coal agglomeration machine according to the present invention, a hole reaching from the outer end of one of the bearings to the outer end of the other of the bearings is provided to allow water to flow through the holes. Alternatively, a hole that penetrates one of the bearing portions and a hole that penetrates the other bearing portion may be provided to allow water to pass through each of the holes.

When providing a hole that reaches from the outer end portion of one of the bearing portions to the outer end portion of the other bearing portion, a pipe is inserted into the hole from the one bearing portion side, and from the one bearing portion side, Water may be supplied into the hole and drained from the pipe extending from the bearing.
Further, when providing a hole penetrating one of the bearing portions and a hole penetrating the other bearing portion, a pipe is inserted into each hole, and water is supplied into the hole from the one bearing portion. It is only necessary to drain from the pipe extending from the pipe, and to supply water into the hole from the other bearing section and to drain from the pipe extending from the bearing section.

  In the method of cooling a roll of a coal agglomerator according to the present invention, the heat generation of the bearing part supporting the bearing part is effectively removed by cooling the bearing parts at both ends of the roll of the double roll type coal agglomerator. Thus, the temperature of the roll surface can be sufficiently lowered. As a result, the agglomeration can be stabilized and the agglomeration yield can be maintained at a high level.

It is a schematic diagram of a double roll type coal agglomerator. (A) is the schematic diagram which showed the pressurization method by the roll of a double roll type coal agglomeration machine, (B) is the schematic diagram which showed the support mechanism of the roll. It is the schematic diagram which showed the method of cooling the roll of the coal agglomerator which concerns on the 1st Embodiment of this invention. It is the schematic diagram which showed the method of cooling the roll of the coal agglomeration machine which concerns on the 2nd Embodiment of this invention. It is the schematic diagram which showed the method of passing water to an agglomerated roll part and one bearing part. It is the schematic diagram which showed the method of water-cooling or air-cooling an agglomerated roll part. It is the graph which showed roll surface temperature and the agglomeration yield about each roll cooling method.

  Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention.

A double roll coal agglomerater 10 for agglomerating coal is shown in FIG.
The double roll type coal agglomeration machine 10 includes a pair of rolls 11 and 12 arranged opposite to each other, a hopper 18 in which coal is stored, and a screw 19 for charging the coal in the hopper 18 into a gap between the rolls 11 and 12. It is roughly composed of

The pair of rolls 11 and 12 are housed in a casing 17, and one roll 11 is a fixed roll and the other roll 12 is a movable roll (see FIG. 2A). As shown in FIG. 2 (B), each roll 11, 12 is located at both ends of the agglomerated roll part 13 for agglomerating coal and the agglomerated roll part 13, and is integrated with the agglomerated roll part 13. The bearing parts 14 and 15 are comprised, and a pair of bearing parts 14 and 15 are supported by the bearing part 16 fitted by each bearing part 14 and 15. FIG.
By pressurizing the bearing portions 14 and 15 of the roll 12 serving as a movable roll with hydraulic pressure, the pair of rolls 11 and 12 are pressed against each other. The roll 12 that is a movable roll is pressed against the roll 11 that is a fixed roll and rotated while being pressed, and the coal discharged from the hopper 18 is caught in the gap between the rolls 11 and 12 so that the coal is agglomerated. Ru.

Next, a method of cooling the roll of the coal agglomeration machine according to the first embodiment of the present invention will be described with reference to FIG.
In the present embodiment, a hole 20 reaching from the outer end of one bearing 14 to the outer end of the other bearing 15 is provided, and the pipe 32 is inserted into the formed hole 20 from one bearing 14 side. To form a double tube.
Here, the “outer end” refers to the end of the bearing 14, 15 which is remote from the agglomeration roll 13. Further, “the hole 20 reaching the outer end portion of the other bearing portion 15” indicates that the hole 20 exists in a portion that is half or more of the axial length of the other bearing portion 15.

The inner diameter of the hole 20 is about 100 mm, and the outer diameter of the pipe 32 is about 50 mm. A gap for water to flow is provided between the bottom of the hole 20 and the tip of the pipe 32. Further, an outer pipe 28 for supplying water to the hole 20 is attached to the inlet of the hole 20 so as to surround the pipe 32 extending from the one bearing portion 14.
When water is supplied into the outer pipe 28, the water supplied into the hole 20 from the outer pipe 28 enters the pipe 32 from the bottom of the hole 20 and is discharged from the rear end of the pipe 32 extending from one bearing portion 14. Be done.

FIG. 4 shows a method of cooling a roll of a coal agglomeration machine according to a second embodiment of the present invention.
In the present embodiment, a hole 21 that penetrates one bearing portion 14 and a hole 22 that penetrates the other bearing portion 15 are provided, and pipes 33 and 34 are inserted into the respective holes 21 and 22. In this Embodiment, the hole which penetrates the agglomerated roll part 13 is not provided, but only a pair of bearing parts 14 and 15 is cooled, and the agglomerated roll part 13 is not cooled.
As in the first embodiment, the water supplied into the hole 21 from the outer pipe 29 attached to the inlet of the hole 21 is discharged from the rear end of the pipe 33 extending from the one bearing portion 14, and the hole 22. The water supplied into the hole 22 from the outer pipe 30 attached to the inlet of the pipe 34 is discharged from the rear end of the pipe 34 extending from the other bearing portion 15.

Next, a verification test performed to verify the effects of the present invention will be described.
In this verification test, the first embodiment is referred to as Example 1 and the second embodiment is referred to as Example 2. Further, for comparison, tests were also performed on comparative examples 1 to 3 with different cooling methods and cases without cooling.

Comparative Example 1 is shown in FIG. In this example, a hole 23 penetrating one of the bearing portion 14 and the agglomeration roll portion 13 is provided, and the pipe 35 is inserted into the hole 23. In this example, the hole which penetrates the other bearing part 15 is not provided, one bearing part 14 and the agglomerated roll part 13 are cooled, and the other bearing part 15 is not cooled.
The water supplied into the hole 23 from the outer pipe 31 attached to the inlet of the hole 23 is discharged from the rear end of the pipe 35 extending from the one bearing portion 14.

Comparative Examples 2 and 3 are shown in FIG. In this example, the cooling nozzle 40 is arranged directly under the agglomerated roll part 13 of the rolls 11 and 12 so that water or air is applied over the entire width of the agglomerated roll part 13.
In Comparative Example 2, 30 L / h of water was sprayed per roll from the cooling nozzle 40 toward the agglomeration roll portion 13. The amount of water is such that the injected water is substantially evaporated and the water content of the coal does not increase.
In Comparative Example 3, air of 300 Nm ³ / h was sprayed per roll from the cooling nozzle 40 toward the agglomeration roll portion 13.

Coal agglomeration was performed as follows.
A tar-based binder was added at 8% by mass to dry pulverized coal with a particle diameter of 1 mm or less, and mixed and kneaded. The coal temperature after kneading was about 70 ° C. This coal was continuously supplied to a double roll coal agglomerator having a diameter of 1 m and a width of 1 m, and agglomerated at a roll reaction force of 180 tons and a roll rotation speed of 10 rpm. The roll surface temperature during agglomeration was measured with a radiation thermometer, and agglomeration was continued under the same conditions until a stable temperature was reached. When the surface temperature of the roll was stabilized, the agglomerated coal was sampled and classified by a classifier, and the mass ratio of a particle size of 1 mm or more was taken as the agglomeration yield.

The results of the verification test are shown in FIG. The following can be understood from the figure.
The surface temperature of the roll was not sufficiently lowered by simply cooling the agglomerated roll part with air or water, and the improvement of the agglomeration yield was low (see Comparative Examples 2 and 3, no cooling). On the other hand, when water was cooled in the roll, the roll surface temperature was relatively decreased and the agglomeration yield was greatly improved (see Examples 1 and 2 and Comparative Example 1). In particular, compared to Comparative Example 1 in which the cooling range is an agglomerated roll part and one bearing part, when both bearing parts are cooled as in Examples 1 and 2, the roll surface temperature is greatly reduced, The improvement in yield was also significant.

  When this cause was examined, it was thought that the heat input from the coal mixture and the heat generation due to the agglomeration load were dominant as the factors that raise the temperature of the roll surface. It turned out that the influence was also great. Therefore, in order to cool the roll surface, it is effective to cool the bearing portion of the roll, and it is defined in the present invention that the bearing portion of the roll is cooled.

  The embodiment of the present invention has been described above, but the present invention is not limited to the configuration described in the above-described embodiment, and considered within the scope of the matters described in the claims. Other embodiments and modifications are also included. For example, in the above embodiment, water is supplied into the hole and drained from the pipe, but water may be supplied into the pipe and drained from the hole.

10: Double roll type coal agglomerating machine, 11, 12: Roll, 13: Agglomerated roll part, 14, 15: Bearing part, 16: Bearing part, 17: Casing, 18: Hopper, 19: Screw, 20, 21 , 22, 23: hole, 28, 29, 30, 31: outer pipe, 32, 33, 34, 35: pipe, 40: cooling nozzle

Claims (4)

  A method for cooling a roll of a coal agglomerator, comprising cooling the bearings at both ends of the roll of a double roll coal agglomerator.   In the method of cooling a roll of a coal agglomeration machine according to claim 1, providing a hole extending from the outer end of one of the bearing portions to the outer end of the other of the bearing portions, and passing water through the hole A method of cooling a roll of a coal agglomerator characterized by the above.   In the method for cooling a roll of a coal agglomeration machine according to claim 2, a pipe is inserted into the hole from the one bearing portion side, water is supplied into the hole from the one bearing portion side, and extended from the bearing portion A method for cooling a roll of a coal agglomerator characterized by draining from the pipe to be discharged.   In the method of cooling a roll of a coal agglomeration machine according to claim 1, a hole is provided through one of the bearing portions and a hole is provided through the other of the bearing portions, and a pipe is inserted into each of the holes; Water is supplied from the bearing portion into the hole and drained from the pipe extending from the bearing portion, and water is supplied from the other bearing portion into the hole and drained from the pipe extending from the bearing portion. A method of cooling a roll of a coal agglomerator characterized.

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