KR100923286B1 - Method for briquetting without binder - Google Patents

Abstract

The present invention relates to a method for producing coal briquettes, and in particular, in the production of coal briquettes, the pre-compression roll mill is passed before the coal briquette manufacturing process, and thus, the strength of the coal briquettes is excellent without using a binder such as molasses or a binder. By not using molasses, it has the advantage of simultaneously solving the troublesome manufacturing process due to the strong viscosity caused by molasses.

Briquettes, 1st Pre-Compression Roll Mill, 2nd Pre-Compression Roll Mill, Compressive Strength

Description

Manufacturing method of binderless coal briquettes {METHOD FOR BRIQUETTING WITHOUT BINDER}

1 is a view showing a plan view and a front view of the first preliminary compression roll mill used in the present invention,

2 is a view showing a plan view and a front view of another type of primary preliminary compression roll mill used in the present invention,

Figure 3 is a view showing the differentiation test results of coal briquettes according to the present invention,

4 is a view showing the results of the differentiation test of coal briquettes in which the preliminary compression process is omitted.

The present invention relates to a method for manufacturing coal briquettes, and more particularly, molasses or polymer added to increase the bonding strength and the compressive strength of coal briquettes by passing a preliminary compression roll mill prior to the operation of a compression roll for producing coal briquettes in the production of coal briquettes. The present invention relates to a method for producing coal briquettes that exhibits excellent strength without using a binder such as a binder.

Conventional coal briquette manufacturing method has been mainly used to use quicklime to remove the moisture in the pulverized coal, and to use a binder to increase the bonding force.

Specifically, a method for producing coal briquettes is known, which comprises mixing and ripening quicklime with pulverized coal, mixing molten molasses as a binder in the aged mixture, and molding the mixed mixture to form coal briquettes. .

U.S. Patent No. 4,738,685 discloses a method for producing coal briquettes by making molasses coal and an inorganic hardener to make coal briquettes for 1 hour at 200 to 300 ° C. In this method, since the curing efficiency is not good, the initial strength is low to cure for 1 to 3 days at room temperature or for 1 hour in an oven at 200 to 300 ℃ to improve the strength of coal briquettes. However, in order to heat the coal briquettes at 200 ° C. or more, a large-scale heat-drying facility is required, which requires a large cost and low productivity.

As described above, the prior arts use a binder such as molasses to maintain the strength of the coal briquettes.

However, the above methods require long working time due to the aging process, and due to the strong viscosity of molasses, molasses grows by attaching to the equipment, resulting in equipment instability due to the increased load and deterioration of workability to produce coal briquettes. It is disrupting the supply.

Another conventional technique discloses a method of manufacturing coal briquettes without using a binder. However, this method uses a force feeder to press coal, which is a raw material of coal briquettes, using a press roll (bracking machine). ) Is a method of manufacturing coal briquettes by supplying raw materials to the die) and compressing the raw materials. However, the strength of the coal briquettes manufactured is inferior to that of the binder coal briquettes, and thus the coal briquettes are broken during the transfer of the coal briquettes and the charging of the coal briquettes. .

The present invention has been made to solve the problems of the prior art as described above, the present invention in the manufacture of coal briquettes used in steel mills, thermal power plants and cement plants, the binder by a pre-compression roll mill process before the coal briquette manufacturing process It is an object of the present invention to provide a method of manufacturing non-binder coal briquettes that can not only provide excellent strength of coal briquettes but also stably manufacture and supply coal briquettes without sacrificing workability due to the use of conventional molasses, and can greatly reduce manufacturing costs. .

In order to achieve the above object, the present invention

In the coal briquette manufacturing method using coal,

Coal briquette production Provides a binderless coal briquette manufacturing method comprising the step of passing a pre-compression roll mill before compression molding by a compression roll.

Preliminary compression roll mill in the present invention is characterized in that it consists of primary and secondary.

Specifically, the present invention,

Conveying coal stored in a coal storage bin to a coal bin through a conveyor belt;

Transferring the coal delivered to the coal bin to a first preliminary compression roll mill in a constant amount of 20 to 30 tonnes per hour to form a sphere or bar;

Transferring the spherical or bar shaped primary preliminary coal briquettes to a second preliminary compression roll mill for compression grinding;

Feeding the pulverized pre-compressed coal into a force screw feeder; And

It provides a binderless coal briquette manufacturing method comprising the step of compressing the coal passing through the force screw feeder in the coal briquette manufacturing compression roll to produce a final coal briquettes.

Hereinafter, the present invention will be described in detail.

Coal conveyed after use as fuel in the steel mill is stored in a storage bin, and then a coal belt conveyor is transferred to the coal bin. The coal transferred to the coal bin is weighed in a constant amount of 20 to 30 tons per hour in a constant feed weight (C.F.W.) and loaded on a conveyer belt conveyor to be transported to the first preliminary compression mill installed continuously.

Primary pre-compression mill used in the present invention is a two-roll mill, grooves are formed on the roll surface as shown in Figs. 1 and 2, when the two rolls are engaged with each other when the grooves rotate to form a space and the inside Coal in the can obtain a circular primary pre-compression coal briquettes as shown in Figure 1 when the groove length is not long, and bar as shown in Figure 2 when the groove is formed long on the roll surface It is possible to obtain the shape of the first pre-compressed coal briquettes.

The depth of the grooves on the surface of the primary preliminary compression roll mill used in the present invention is preferably 10 to 20 mm, preferably 13 to 15 mm, for workability in the secondary pre-extrusion roll mill. The primary preliminary compression roll mill in the present invention has a speed of 10 to 20 rpm, and the pressure is preferably controlled to a linear pressure of 2 to 4 ton / cm.

The primary pre-compression briquettes obtained as described above are continuously transferred to a secondary pre-compression roll mill. The secondary pre-compression roll mill used in the present invention is a two-roll mill, which is a roll mill having a smooth or rough surface. Use The coal briquettes passed through the second preliminary compression roll mill are compressed and crushed to obtain a powder form.

Secondary pre-compression roll mill used in the present invention is fixed on one side, only the opposite roll is rotated, the pressure is controlled to about 200 to 250 kg / ㎠. If foreign matters are contained in the first preliminary compacting coal conveyed to the second preliminary compression roll mill, the control pressure is out of the range, and the roll is pushed backward to stop the work.

The particle size of the pre-compressed coal briquettes pulverized in the secondary pre-compression roll mill is at most 10 mm or less, preferably 5 mm or less in view of the overall characteristics of the coal briquettes.

In the present invention, the preliminary compression mill was carried out continuously in the first and second, that is, twice, which is not preferable because the primary alone cannot bring the strength of the coal briquettes formed without a binder, and from the third or more, Since the improvement in strength does not increase proportionally, it is most preferable to pass the preliminary compression roll mill up to the secondary in terms of equipment cost, workability, and compressive strength.

The preliminary coal briquettes passed through the primary and secondary preliminary compression roll mills are passed through a roller press, which is a coal briquetting machine that produces coal briquettes through a force screw feeder to obtain final coal briquettes.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by the following Examples.

Example 1

The coal stored in the coal storage bin is transferred to the coal bin through the belt conveyor, and then preliminarily pre-compressed into a two-roll mill with a groove depth of about 14 mm at a constant amount of 25 ton (36 rubes) per hour. The primary preliminary coal briquettes of were obtained. The obtained primary preliminary coal briquettes were transferred to a two-roll mill having a smooth surface, subjected to secondary preliminary compression at a pressure of 250 kg / cm 2, and compacted to a size of about 5 mm. The pulverized compressed pre-coal briquettes were obtained by a force screw feeder with a coal briquette having a width of 47 mm and a thickness of 28 mm at a pressure of 200 kg / cm 2 at a press roll.

Example 2

Coal briquettes were obtained in the same manner as in Example 1, except that in Example 1, a 2-roll mill in which the surface shape of the first preliminary compression roll mill had long grooves was used.

Comparative Example 1

Coal briquettes of the same size as in Example 1 were obtained through a press roll, which is a coal briquette making machine using only coal, without undergoing primary and secondary preliminary compression processes according to the present invention.

Property test

* Differentiation Test: After dropping 2,011 and 2,002 g of coal briquettes at a height of 5 m, it was expressed as% of coal briquettes having a size of 19 mm or more, 9.7 mm or more, 6.7 mm or more and 6.7 mm or less.

* Compressive strength: It indicates the maximum strength when compressed by SPG Co.

Differentiation test results, compressive strength and specific gravity of the coal briquettes obtained by Examples 1 and 2 and Comparative Examples are shown in Tables 1 and 2, and FIGS. 3 and 4.

TABLE 1

division Test amount Particle size distribution 19 mm or more 9.7 mm or more 6.7mm or more 6.7mm or less Coal briquettes manufactured without precompression 2,011 g 834 g 266 g 115 g 796 g Share 100% 41.5% 13.2% 5.7% 39.6% Coal briquettes manufactured after the first and second precompression 2,002 g 1160 g 260 g 100 g 482 g Share 100% 58% 13% 5% 24%

As can be seen through Table 1, and Figure 3, when looking at the differentiation state of the coal briquettes according to the present invention, the granular coal according to the comparative example as shown in FIG. The powder generation rate is high and the size after the differentiation is smaller than the coal briquettes according to the present invention.

This indicates that the bonding force between coals is increased even without the binder during the first and second preliminary compression processes according to the present invention.

Table 2 is a table comparing the specific gravity and strength of the coal briquettes prepared according to the present invention and the coal briquettes prepared by the comparative example.

TABLE 2

division Coal Coal briquettes importance Remarks importance burglar Remarks Coal briquettes manufactured without precompression 0.68 Specific gravity: 0.22 increase 1.15 3 ~ 7kg / ㎠ Specific gravity: 0.1 Increased strength: 7-13 kg / ㎠ increase Coal briquettes manufactured after two preliminary compressions 0.9 1.25 10 ~ 20kg / ㎠

As can be seen from Table 2, not only the specific gravity was increased through the preliminary compression process, but also the strength was significantly increased from 3 to 7 to 10 to 20 kg / cm 2.

According to the method for manufacturing coal briquettes according to the present invention as described above, the strength of the coal briquettes is not only excellent without using molasses or a binder, which is a binder that maintains the strength of the coal briquettes. Therefore, there is no phenomenon that impurities are deposited in the equipment during long time operation, there is an advantage that workability is improved.

The present invention described above is not limited to the detailed description and examples of the above-described invention, and various modifications are made by those skilled in the art without departing from the spirit and scope of the present invention described in the claims below. And modifications are also included within the scope of the invention.

Claims (5)

In the coal briquette manufacturing method using coal, Before compression molding by the coal briquette manufacturing press roll, The first step of conveying the coal into a spherical or bar shape by transferring to a first preliminary compression roll mill consisting of a two-roll mill having grooves on the surface, and the spherical or bar shaped primary pre-compressed coal A method of manufacturing a binderless coal briquette comprising the step of passing through a precompression roll mill comprising a second step of transferring to a second preliminary compression roll mill made of a smooth two-roll mill and compressing and crushing. delete The method of claim 1, Compression molding by the coal briquette manufacturing press roll Supplying the compression milled pre-compressed coal into a force screw feeder; And, Binder coal briquette manufacturing method comprising the step of compressing the coal passing through the force screw feeder in the coal briquette manufacturing compression roll to produce a final coal briquettes. delete delete

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