KR20190005649A - Method for manufacturing coal briquettes and coal briquettes using the same - Google Patents

Abstract

The present invention relates to a method for manufacturing coal briquettes and coal briquettes manufactured by using the same. The method comprises the steps of: preparing a raw material containing pulverized coal and dextrin; mixing the raw material to prepare a mixture; aging the mixture; and molding the aged mixture to manufacture coal briquettes. The generation of low-melting point compounds can be inhibited in the production of molten iron, thereby preventing the equipment from being damaged by deposits.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of manufacturing a molded coal and a method of manufacturing the same,

More particularly, the present invention relates to a method of manufacturing a molded coal capable of preventing the clogging of a pipe in a melter-gasifier during molten iron production, and a molded carbon produced using the method.

In the steel mills around the world, the melting and reducing steelmaking method has been developed, in which general coal is directly used as a fuel and reducing agent, and iron ore, which occupies more than 80% of the world ore production, is directly used as iron source.

In the melting reduction steelmaking method, reduced iron and iron reduced by iron ore are charged into a melter-gasifier, the oxygen-containing gas is blown into the melter-gasifier, the molten iron is burned, and the reduced iron is melted by using heat generated when the molten- The charcoal is manufactured.

On the other hand, the briquette can be produced by mixing pulverized coal and a binder, and press-molding a mixture of pulverized coal and a binder in a molding machine. The blast furnace is used as a fuel material in the production of molten iron. In order to stably load the molten gas into the melting gasification furnace, it is necessary to have a cold strength and a hot strength. And molasses or the like having excellent viscosity as a binder is used.

However, since molasses is different in its composition depending on its origin and it is difficult to control its components according to the sugar manufacturing process, the quality of the molten carbonate can not be controlled uniformly when molasses is used as a binder.

Since molasses contains a large amount of an alkali component, when a molten gas produced by molasses is used in a melter-gasifier, a large amount of low melting point compounds such as KCl is generated. The low-melting point compound thus formed is contained in the reducing gas, clogging the pipe through which the reducing gas is discharged, and is adhered to the inside of the fluidized-bed reactor for producing the reduced iron by using the reducing gas.

KR 0627469 B KR 10-2017-0018275 A

The present invention provides a method for producing a molded-formed carbon capable of inhibiting the formation of a low-melting-point compound, and a molded carbon produced using the method.

The present invention provides a method of manufacturing a shaped coal capable of improving operational efficiency and productivity by suppressing equipment damage, and a molded carbon produced using the method.

A method for manufacturing a molded coal according to an embodiment of the present invention includes the steps of: preparing a raw material containing pulverized coal and dextrin; Mixing the raw materials to prepare a mixture; Aging the mixture; And a step of molding the aged mixture to produce a blast furnace.

And a step of preparing dextrin having DE (Dextrose Equivalent) of more than 0 and 10 or less in the process of preparing the raw material.

And a step of preparing dextrin having a particle size of 10 to 20 탆 in the process of preparing the raw material.

The process for preparing the mixture may include mixing 91 to 97 wt% of the pulverized coal and 3 to 9 wt% of the dextrin with respect to the total weight of 100 wt% of the pulverized coal and the dextrin combined.

The aging may include heating the mixture using steam to maintain the temperature at 50 to 100 ° C.

In the aging process, the mixture may be adjusted to have a moisture content of 3 to 10 wt% with respect to 100 wt% of the entire mixture.

In the aging process, the ratio of the amount of water to the amount of dextrin may be adjusted to 1 to 3.

The aging may include stirring the mixture.

The aging process may be performed for 7 to 20 minutes.

The briquette according to the embodiment of the present invention includes pulverized coal and dextrin, and the dextrin may exist in a gelled state.

According to the embodiments of the present invention, it is possible to produce molded charcoal having excellent strength using dextrin which does not contain calcium (K), which is an alkali component, as a binder. Therefore, it is possible to secure the strength of the briquette and to inhibit or prevent the formation of the low melting point compound due to the alkali component when the molten iron is produced using the briquette. This makes it possible to inhibit the clogging of piping and the formation of deposits in the facility by a low melting point compound. For example, it is possible to suppress the clogging of pipes in the melting and gasifying furnace, and to prevent clogging of the dispersion plate and the like of the fluidized-bed reactors. In addition, since the facility can be stably operated, maintenance and repair of the facility can be facilitated, and operational efficiency and productivity can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view schematically showing a configuration of a molten iron manufacturing apparatus according to an embodiment of the present invention; FIG.
FIG. 2 is a schematic view showing a configuration of a molding machine according to an embodiment of the present invention; FIG.
3 is a flow chart sequentially illustrating a method of manufacturing a briquette according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. In the drawings, the size is exaggerated or enlarged in order to clearly illustrate the various elements, and the same reference numerals denote the same elements in the drawings.

Before describing the present invention, the configuration of the chartering machine will be described.

FIG. 1 is a view schematically showing a configuration of a molten iron manufacturing apparatus according to an embodiment of the present invention, and FIG. 2 is a view schematically showing the configuration of a molten iron manufacturing apparatus according to an embodiment of the present invention. In Fig. 1, the solid line indicates the movement path of the raw material, and the dotted line indicates the movement path of the gas.

1, a molten iron manufacturing apparatus includes a fluidized-bed reactor 200 for producing reduced iron by reducing iron ore, a molten-gasification furnace 100 for producing molten iron using a reduced- . ≪ / RTI > Further, the molten iron manufacturing apparatus may include a molding apparatus 400 for molding the reduced iron into a coarse light in a hot state.

The fluidized-bed reactor 200 is a means for producing reduced iron by reducing iron ore. The iron ore may be a minute iron ore, and may be supplied with additives if necessary. That is, a space for reducing iron ores can be formed in the fluidized-bed reactor 200, and a dispersion plate capable of uniformly diffusing a gas supplied into the fluidized-bed reactor 200, such as a reducing gas, Can be installed. Thus, the fluidized-bed reduction reactor 200 can reduce the iron ores while flowing the reducing gas therein. A plurality of such fluidized-bed reactors 200 may be provided, and the iron ores may be made of reduced iron while sequentially moving the plurality of fluidized-bed reactors 200. For example, the fluidized-bed reactor may have three fluidized-bed reactors (hereinafter, referred to as a first fluidized-bed reactor 201, a second fluidized-bed reactor 202, and a third fluidized-bed reactor 203). At this time, the first fluidized-bed reactor 201 can dry and preheat the iron ores using the exhaust gas and the reducing gas discharged from the second fluidized-bed reactor 202 where the iron ore is initially charged. The iron ores that have been dried and preheated in the first fluidized-bed reactor 201 are reduced or preliminarily reduced through the second fluidized-bed reactor 202 and the second fluidized-bed reactor 202 is returned to the third fluidized- The iron ore can be reduced by the discharged exhaust gas and the reducing gas. And the third fluidized-bed reactor 203 can finally reduce the iron ores by the reducing gas discharged from the melter-gasifier 100. The number of fluidized-bed reactors 200 is not limited to this, and can be adjusted as needed.

The molding apparatus 400 can reduce the reduced iron produced in the fluidized-bed reactor 200, that is, the reduced iron in the finely divided state, in a hot state. The molding apparatus 400 includes a first reservoir 410 for storing reduced iron discharged from the fluidized-bed reactor 200, and a reduced-iron reduced iron such as a briquettes supplied from the first reservoir 410 And a second reservoir (not shown) for temporarily storing the molded body manufactured by the first molding machine 420 and supplying the molded body to the melter-gasifier 100. At this time, the first molding machine 420 may be a twin roll type molding machine having a pair of rolls arranged to face each other. Thus, when the reduced iron in the powder state is charged between the pair of rolls, the reduced iron compacted by extrusion due to the rotation of the pair of rolls can be manufactured.

The apparatus 300 for producing molded coal may pressurize a mixture of pulverized coal and a binder to produce a blast furnace, and charge the blast furnace to the molten gasification furnace 100. The apparatus 300 for producing molded coal includes a mixer 310 for mixing pulverized coal and a binder, an aging unit 320 for aging a mixture of pulverized coal and a binder mixed in the mixer 310, And a third reservoir 340 for storing the briquetted coal and charging it into the melter-gasifier 100. Here, the mixer 310 may be a drum mixer formed with a space capable of receiving pulverized coal and a binder therein, and formed to be rotatable. The aging machine 320 includes a body 322 having a space for receiving a mixture of pulverized coal and a binder therein, an agitator 324 capable of agitating the mixture, And may include steam supply means 326,

The configuration and structure of the briquette supplying device 300 are not limited to this, and may be modified into various forms.

The melting and gasifying furnace 100 may be provided with an inner space capable of producing molten iron by dissolving the reduced iron reduced in the molding apparatus and producing a reducing gas to be supplied to the fluidized-bed reactors 200. The melter-gasifier (100) has a lower space in which a carbonaceous material such as reduced iron, molded coal and algae is received and a molten iron is manufactured, and a lower space in which the exhaust gas generated in the process of manufacturing molten iron is supplied to the fluidized- And an upper space for making the gas. At this time, the upper space may be formed into a dome shape wider than the lower space, and the reduced iron and the carbon material (molding coal) may be charged through the upper space. The melter-gasifier 100 may be provided with a tuyere (not shown) through which an oxygen-containing gas for burning the carbonaceous material is blown to secure a heat source for melting the reduced iron.

The melter-gasifier 100 may further include a blowing nozzle (not shown) for supplying an oxygen-containing gas to remove volatile substances such as tar generated in the process of dissolving the reduced iron. When carbonaceous materials such as a molding bath and an algae are charged into the melter-gasifier 100, volatile substances such as tar are generated during the heating process. When such volatile materials are discharged to the outside of the melter-gasifier 100, A problem arises. In this case, oxygen-containing gas is blown into the upper space of the melter-gasifier 100 into which volatile substances are introduced to burn carbon monoxide, carbon dust, etc., and the temperature of the upper space is raised to about 900 to 1100 ° C The volatile material can be converted into carbon monoxide (CO) and hydrogen gas (H ₂ ) through a high-temperature chemical cracking process and discharged from the melter-gasifier 100.

Hereinafter, a method of manufacturing a molded product according to an embodiment of the present invention will be described.

FIG. 3 is a flowchart illustrating a method of manufacturing a shaped coal according to an embodiment of the present invention.

Referring to FIG. 3, the method for producing molded coal according to an embodiment of the present invention includes a step (S100) of preparing a raw material containing pulverized coal and a binder, a step (S110) of preparing a mixture by mixing the raw materials, (S120) a process of aging (S120), and a process of forming a shaped coal using the aged mixture (S130). At this time, the binder may include dextrin. In addition, the method of manufacturing a molded coal according to an embodiment of the present invention may further include an additional process in addition to the processes shown as necessary.

In the process of preparing the raw materials, carbonaceous materials such as bituminous coal, subbituminous coal, anthracite and coke can be used. The pulverized coal preferably has a uniform particle size distribution of the pulverized coal in order to reduce variations in the quality of the pulverized coal. The pulverized coal preferably has a particle size distribution of not more than 90% by weight and not more than 80% Of the average particle size. The pulverized coal can be used after crushing the coking coal so as to have a particle size in the range shown and then selecting the particle size. The pulverized coal may contain about 3 to 10 wt% of water relative to 100 wt% of the whole pulverized coal. In this case, in order to control the water content in the pulverized coal, the step of drying the pulverized coal or the pulverized coal may be further included in the process of preparing the pulverized coal.

And the binder may include dextrin. Dextrin is produced by hydrolyzing starch with acid, heat, enzyme, etc. and can be produced by hydrolyzing various starches such as corn, wheat, tapioca, potato, rice and the like. Dextrin can be manufactured in a wide range from low molecular weight starch slightly decomposed to low molecular weight ones showing no iodine-starch reaction. Depending on the degree of hydrolysis of the starch, three types of dextrin are produced: white, pale yellow and yellow. White is a high molecular weight dextrin and yellow is a low molecular weight dextrin.

The dextrose equivalent (DE) of dextrin can be from about 0 to about 10, preferably from about 0 to about 5. DE of dextrin is a measure of how much starch formed by glucose binding is decomposed to produce glucose. The higher the DE, the greater the degradation, and when it is completely degraded and becomes glucose, the DE is denoted as 100. If the DE of dextrin exceeds 10, the decomposition of the starch is too much, and the bonding strength to pulverized coal may be deteriorated, which may cause a problem in that the strength of the briquette is lowered. Therefore, it is possible to secure the strength of the briquette by using dextrin having DE in the range shown.

Dextrin does not contain alkaline components such as potassium (K). Therefore, the use of briquettes made of dextrin as a fuel material in the production of molten iron can inhibit the generation of low melting point compounds such as KCl generated by alkali components in the exhaust gas. Therefore, the phenomenon that the pipe of the melter-gasifier is clogged by the low-melting-point compound or the clogging of the dispersion plate or the like of the fluidized-bed reduction reactor can be suppressed.

The dextrin may be provided in a powder state and may have a particle size of about 10 to 20 mu m. In this case, when the particle size of dextrin is larger than the indicated range, it is not uniformly distributed in the pulverized coal when mixed with the pulverized coal, so that the bonding force to the pulverized coal may be lowered. If the particle size of the dextrin is within the range, it is possible to uniformly distribute the dextrin in the pulverized coal to ensure a sufficient contact area with the pulverized coal, and it is not necessary to be smaller than the range shown.

On the other hand, when a binder in a liquid state is used, the flowability of the binder and the pulverized coal mixture is lowered due to a high moisture content, so that adhesion occurs during the production of the shaped coal, and the mixture is unevenly charged into the molding machine So that the phenomenon that the strength and shape of the briquettes become uneven occurs. In addition, since the briquette thus produced has a high moisture content, a drying process must be additionally performed before charging it into the melter-gasifier in order to secure the strength of the briquette, thereby increasing the overall process time and cost, . In addition, the binder in the liquid state is difficult to maintain the binder component uniformly due to the layer separation, and the transportation cost is high due to the need for special transportation vehicle such as a tank lorry during transportation, and it is frozen in winter, so storage is not easy.

In contrast, when a powdery binder is used, the flowability of the pulverized coal and the binder mixture is improved, and uniform molded coal can be produced. Further, when a binder in a powder state is used in the production of the briquettes, the strength of the briquette can be sufficiently secured without further drying before being used for operation. In addition, the binder in a powder state minimizes its volume and is easy to store and transport, and there is no need to worry about freezing in winter.

When the raw material, that is, the pulverized coal and the dextrin as a binder are prepared, the mixture is uniformly mixed in the mixer 310 to prepare a mixture. At this time, pulverized coal may be contained in an amount of 91 to 97 wt% and dextrin may be contained in an amount of 3 to 9 wt% based on 100 wt% of the whole mixture. Preferably, 93 to 97 wt% of pulverized coal and 3 to 7 wt% of dextrin can be contained with respect to 100 wt% of the whole mixture. When the content of the binder is less than the range shown in Table 1, the strength of the briquette to be produced can not be sufficiently secured, and when the content of the binder is larger than the range, the cost for producing the briquette increases.

The mixture thus prepared may contain about 3 to 10 wt% of water relative to 100 wt% of the mixture. At this time, when the amount of water contained in the mixture is less than the indicated range, the inside of the aging unit 320 may be put into a supersaturated vapor state in a subsequent aging process to add water to the mixture. The ratio of the amount of water to the amount of dextrin can be about 1 to 3. This is to ensure smoothness of gelatinization of the dextrin during the aging process and to secure the viscosity. If the moisture content is less than the indicated range, the dextrin gelation reaction does not occur smoothly, I can not. If the moisture content is higher than the above-mentioned range, the water content of the molded coal increases, and a drying process must be additionally performed to secure the strength. However, when the amount of water in the mixture is less than the indicated range during the preparation of the mixture, the water content in the body 322 can be adjusted to the indicated range by controlling the vapor pressure in the course of aging the mixture.

When the mixture is prepared, the mixture is charged into the body 322 of the aging machine 320, and the mixture is aged while supplying steam into the body 322 through the steam supply means 326.

The aging process may be performed under the condition that the internal pressure of the body 322 is 5 to 10 bar and the internal temperature of the body 322 is 110 ° C or more. During aging of the mixture, the internal environment of the body 322 can be controlled such that the mixture is maintained at 50 to 100 캜, preferably at 50 to 100 캜. If the temperature of the mixture is higher than the indicated range, it takes a lot of energy to increase the temperature of the mixture, which is not desirable from the viewpoint of the process efficiency. If the temperature of the mixture is lower than the prescribed range, the dextrin- It is difficult to produce a molded coal.

The agitator 324 may be used to agitate the mixture during the aging process. When the mixture is stirred using the agitator 324, the temperature of the mixture can be uniformly adjusted as a whole. When the mixture is agitated by the agitator 324, the mixture and the agitator 324 come into contact with each other to generate frictional heat. The frictional heat thus generated can be used as a heat source to cause a dehydrogenation reaction of dextrin with the steam supplied into the body 322.

When the mixture is aged in this manner, the dextrin uniformly dispersed in the pulverized coal meets the moisture, and when the temperature inside the body 322 of the aging machine 320 is increased, do. As a result, the hydrolyzed dextrin exhibits the binding force against the pulverized coal, and the strength of the briquettes produced in the subsequent process can be greatly improved.

The aging time of the mixture can be performed for about 7 to 20 minutes. At this time, the aging time can be longer than the mixing time of the raw material, so that the dextrin is uniformly and sufficiently smoothed in the pulverized coal. In addition, since raw materials, that is, pulverized coal and dextrin are provided in powder form, it takes much time to uniformly mix them. However, since the dextrin is aged in the aging process, to be. The aging time is preferably 2 to 5 times longer than the time for preparing a mixture of pulverized coal and dextrin.

When the aging process is completed, the mixture is taken out from the body 322 of the aging machine 320 and charged into the second molding machine 330 to produce a blast furnace. The briquettes can be manufactured by charging the aged mixture between a pair of rollers, followed by pressing, and can be formed into various shapes such as briquettes and strips. When the briquettes are manufactured, the molding pressure can be adjusted so that the briquettes to be produced have an apparent density of about 1.25 to 1.35 kg / m3. Thus, the briquettes having the strength that can be used in the melting and gasifying furnace can be produced.

The bins thus formed may be temporarily stored in the third reservoir 340 and then charged into the melter-gasifier 100 for the production of molten iron.

Hereinafter, an experimental example for verifying the physical characteristics of the briquette produced by the embodiment of the present invention and the effect obtained when the briquetting charcoal is applied to actual operation will be described.

Briquette Hot Strength  And Cold strength  Measurement experiment

The pulverized coal and dextrin powder having a particle size of 3.4 mm or less and having a particle size of 90% or more were homogeneously mixed for 2 to 3 minutes and then added to the aging machine and the steam was supplied into the aging machine to raise the temperature inside the aging machine and aged for a certain period of time . At this time, as the pulverized coal, a blend of tough coal, unripe coal and minute coke was used. As a dextrin, WSCR Wheat Dextrin product of MANILDRA was used. During aging, the mixture of pulverized coal and dextrin was stirred using a stirrer.

Then, the aged mixture was charged into a pair of rolls of a second molding machine to produce a blast furnace. The rolls of the second molding machine were pressurized with a pressure of 20 kN / cm to produce 64.5 mm x 25.4 mm x 19.1 mm sized pillow-shaped molded briquettes.

Experimental Example 1

95.5 wt% of pulverized coal having a moisture content of 7.6 wt% and 4.5 wt% of powdered dextrin were mixed for 3 minutes and aged for 10 minutes. At this time, dextrin having a DE of 2 was used, and the moisture content of the aged mixture discharged from the aging period was 7.4 wt% and the temperature was 62 ° C. And the mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was manufactured, it was allowed to stand at room temperature for about 1 hour, and the drop strength and compression load were measured. The falling strength of the briquettes was determined from the ratio of the briquette having a particle size of 20 mm or more after freely dropping 2 kg of the briquettes produced by the respective examples at a height of 5M eight times. The compressive load of the briquette was measured as the maximum load when the bottom of the briquette was compressed at a constant speed at the top of the briquette.

Experimental Example 2

95.5 wt% of pulverized coal having a moisture content of 8.0 wt% and 4.5 wt% of powdered dextrin were mixed for 3 minutes and aged for 15 minutes. At this time, dextrin having a DE of 2 was used, and the moisture content of the aged mixture discharged from the aging period was 6.9 wt% and the temperature was 68 ° C. And the mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was produced, the drop strength and the compression load were measured in the same manner as in Experimental Example 1.

Experimental Example 3

95.5 wt% of pulverized coal having a moisture content of 6.2 wt% and 4.5 wt% of powdered dextrin were mixed for 3 minutes and then aged for 10 minutes. At this time, dextrin having a DE of 2 was used, and the moisture content of the aged mixture discharged from the aging period was 5.4 wt% and the temperature was 63 ° C. And the mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was produced, the drop strength and the compression load were measured in the same manner as in Experimental Example 1.

Experimental Example 4

95.0 wt% of pulverized coal having a moisture content of 9.8 wt% and 5.0 wt% of powdered dextrin were mixed for 3 minutes and then aged for 10 minutes. At this time, dextrin having a DE of 2 was used, and the moisture content of the aged mixture discharged from the aging period was 8.5 wt% and the temperature was 66 ° C. And the mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was produced, the drop strength and the compression load were measured in the same manner as in Experimental Example 1.

Experimental Example 5

97.5 wt% of pulverized coal having a moisture content of 7.6 wt% and 2.5 wt% of powdered dextrin were mixed for 3 minutes and then aged for 10 minutes. At this time, dextrin having a DE of 2 was used, and the moisture content of the aged mixture discharged from the aging period was 7.2 wt% and the temperature was 63 ° C. And the mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was produced, the drop strength and the compression load were measured in the same manner as in Experimental Example 1.

Experimental Example 6

95.5 wt% of pulverized coal having a moisture content of 6.0 wt% and 4.5 wt% of powdered dextrin were mixed for 3 minutes and then aged for 5 minutes. At this time, dextrin having a DE of 2 was used, and the moisture content of the aged mixture discharged from the aging period was 5.8 wt% and the temperature was 63 ° C. And the mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was produced, the drop strength and the compression load were measured in the same manner as in Experimental Example 1.

Experimental Example 7

95.5 wt% of pulverized coal having a moisture content of 7.5 wt% and 4.5 wt% of powdered dextrin were mixed for 3 minutes and the process of aging in an aging machine was omitted. At this time, dextrin having a DE of 2 was used. Then, the aged mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was produced, the drop strength and the compression load were measured in the same manner as in Experimental Example 1.

Experimental Example 8

95.5 wt% of pulverized coal having a moisture content of 7.5 wt% and 4.5 wt% of powdered dextrin were mixed for 3 minutes and then treated for 10 minutes in an aging machine. Dextrin having a DE of 42 was used, and the moisture content of the aged mixture discharged from the aging period was 7.1 wt% and the temperature was 62 ° C. And the mixture was charged between a pair of rolls to produce a blast furnace. When the blast furnace was produced, the drop strength and the compression load were measured in the same manner as in Experimental Example 1.

The results of Experimental Examples 1 to 8 are shown in Table 1 below.

Experimental Example Compounding ratio (wt%) The aged mixture Briquette quality Pulverized coal dextrin Aging time (min) moisture
(wt%) Temperature
(° C) Drop strength (%) Compressive load
(Kgf) Experimental Example 1 95.5 4.5 10 7.4 62 90 62 Experimental Example 2 95.5 4.5 15 6.9 68 88 78 Experimental Example 3 95.5 4.5 10 5.4 63 78 69 Experimental Example 4 95.0 5.0 10 8.5 66 97 74 Experimental Example 5 97.5 2.5 10 7.2 63 49 37 Experimental Example 6 95.5 4.5 5 5.8 63 62 49 Experimental Example 7 95.5 4.5 0 7.5 25 24 14 Experimental Example 8 95.5 4.5 10 7.1 62 57 44

Referring to Table 1, in the case of Experimental Examples 1 to 4 produced by the method of producing a molded carbon according to the present invention, it is found that the falling acceleration and the compression load of the briquette are measured very well. That is, in the case of the briquette produced under the conditions shown in the method of the present invention, the drop strength was 70% or more and the compression load was 60 kgf or more.

However, in the case of Experimental Example 5, in which the dextrin content was smaller than the range suggested in the present invention, the falling strength and compressive load of the briquette were measured lower than those in Experimental Examples 1 to 4.

Also, in the case of Experimental Example 6 in which the aging was shortened in the range as shown in the present invention and Experimental Example 7 in which the aging was not carried out, the falling strength and compressive load of the briquette were lower than those in Experiments 1 to 4.

In the case of Experimental Example 8 using dextrin having a DE of 42 in textlin, the drop strength and the compression load of the briquettes were also lower than those of Experiments 1 to 4 Respectively.

As a result, it can be seen that when the content of the raw materials and the process conditions are satisfied, the strength of the briquette can be sufficiently secured.

An experiment for examining the degree of formation of a low-melting point compound or the like when the blast furnace produced by the present invention is used for actual operation will be described.

Experimental Example 9

The briquettes produced in Experimental Example 4 were pulverized into a pulverized state. Then, about 7 g of crushed molded charcoal, for example, Sample 1, was charged into a 30 ml magnetic crucible. Then, the furnace crucible was charged into a heating furnace at 850 DEG C and then heated for 10 hours to burn the sample 1. Then, the components of the burned sample 1 were analyzed.

Experimental Example 10

2.7 parts by weight of quicklime and 11 parts by weight of molasses were uniformly mixed with 100 parts by weight of pulverized coal having a particle size of 3.4 mm or less and 90% or more. Then, the mixture was charged into a pair of rolls to produce a blast furnace. At this time, the same molding pressures as in Experimental Example 4 were used in the production of briquette to produce molded briquettes of the same size. The briquettes thus produced were pulverized into a pulverized state. Then, about 7 g of crushed molded charcoal, for example, sample 2, was charged into a 30 ml magnetic crucible. Then, the crucible was charged into a heating furnace at 850 DEG C and then heated for 10 hours to burn the sample 2. [ The components of the burned sample 2 were then analyzed.

Table 2 below shows the results of analyzing the components of Samples 1 and 2.

division Ash Component (wt%) SiO ₂ CaO Al ₂ O ₃ MgO TiO ₂ Fe ₂ O ₃ K ₂ O Na ₂ O Experimental Example 9 50.9 8.2 24.3 2.2 1.3 8.2 1.9 0.8 Experimental Example 10 38.8 27.3 20.2 2.2 1.0 4.6 3.3 0.3

In Table 2, it can be seen that the amount of alkali component, i.e., K ₂ O, which forms deposits on piping or equipment, is remarkably reduced in comparison with the briquettes produced by using molasses, in the case of the briquettes produced using dextrin . Since the dextrin used as the binder does not contain the K component, it is preferable that K ₂ O is not detected after the sample 1 is burned. However, since the K ₂ O component is partially contained in the pulverized coal, Respectively.

When the briquettes produced using dextrin are used in the melter-gasifier, the formation of a low-melting point compound (melting point 770 ° C) such as KCl produced by the alkali component can be suppressed. Therefore, it is possible to stably operate the facility by inhibiting the formation of deposits by the low melting point compound in the fluidized-bed reactor in which iron ore is reduced by using the reducing gas generated from the melter-gasifier or when the piping of the melter- .

Although the technical idea of the present invention has been specifically described according to the above embodiments, it should be noted that the above embodiments are for explanation purposes only and not for the purpose of limitation. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

100: melt gasification furnace 200: fluidized-bed reduction furnace
300: Molded-coal supply device 400: Molding device

Claims (10)

Preparing a raw material containing pulverized coal and dextrin;
Mixing the raw materials to prepare a mixture;
Aging the mixture;
A step of molding the aged mixture to produce a shaped coal;
≪ / RTI > The method according to claim 1,
In the process of preparing the raw material,
And a dextrin having DE (Dextrose Equivalent) of more than 0 and 10 or less. The method of claim 2,
In the process of preparing the raw material,
Providing a dextrin having a particle size of 10 to 20 占 퐉. The method of claim 3,
The process for preparing the mixture comprises:
The method comprising mixing 91 to 97 wt% of the pulverized coal and 3 to 9 wt% of the dextrin with respect to a total weight of 100 wt% of the pulverized coal and the dextrin combined. The method of claim 4,
The above-
And heating the mixture using steam to maintain the temperature at 50 to 100 占 폚. The method of claim 5,
During the aging process,
And adjusting the mixture to have a water content of 3 to 10 wt% with respect to 100 wt% of the whole mixture. The method of claim 6,
During the aging process,
And adjusting the ratio of the amount of water to the amount of dextrin to 1 to 3. The method of claim 7,
The above-
And stirring the mixture. The method of claim 8,
Wherein the aging process is performed for 7 to 20 minutes. It contains pulverized coal and dextrin,
The dextrin is present in a gelled state.

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