KR20210055305A - Coal briquettes, and method for manufacturing the same - Google Patents

Abstract

According to an embodiment of the present invention, provided are coal briquettes, a method for manufacturing the same, and an apparatus for manufacturing the coal briquettes. The coal briquettes charged in a dome part of a gasification melting furnace in a molten iron manufacturing device and heated rapidly contain raw coal, and rice powder binder. The damaged starch content in the rice powder binder is more than 5 wt%.

Description

Briquettes, and a manufacturing method thereof {COAL BRIQUETTES, AND METHOD FOR MANUFACTURING THE SAME}

It relates to coal briquettes, and a method of manufacturing the same. More specifically, it relates to coal briquettes to which a rice powder binder is applied, and a method of manufacturing the same.

In the melt-reduction steelmaking method, a reduction furnace for reducing iron ore and a melting gasification furnace for melting the reduced iron ore are used. In the case of melting iron ore in the melting gasifier, coal briquettes are charged into the melting gasifier as a heat source to melt the iron ore. Reduced iron is melted in a melting gasifier, converted into molten iron and slag, and then discharged to the outside. The coal briquettes charged in the melter gasification furnace form a coal filling layer. Oxygen is blown in through a windpipe installed in the melting gasifier, and then the coal-filled bed is combusted to generate combustion gas. As the combustion gas rises through the coal-filled bed, it is converted into a high-temperature reducing gas. The high-temperature reducing gas is discharged to the outside of the melting gasifier and supplied to the reduction furnace as a reducing gas.

Briquettes are manufactured by mixing pulverized coal and a binder and then compressing them. In order to be used for manufacturing molten iron, it is necessary to manufacture coal briquettes having excellent cold strength and hot strength. Therefore, the binder used for coal briquettes is required to have excellent adhesion and high strength at high temperatures.

In the case of the binder used in the existing coal briquettes for manufacturing molten iron, corn starch containing more than 99% starch on a dry basis is mainly used. However, in order to manufacture corn starch, there is a problem that a large-scale facility is required and the manufacturing cost is increased due to complex processes such as selection (remove foreign substances), immersion (acid treatment), crushing, embryo separation, oxidel separation, and gluten separation. .

In order to solve the above problems, it is intended to provide a method of manufacturing coal briquettes having excellent hot strength and cold strength by providing a water content and pulverization conditions capable of securing adhesive strength necessary for using rice as a binder.

The coal briquettes according to an embodiment of the present invention are loaded into the dome of the melting gasification furnace in a molten iron manufacturing apparatus including a melting gasification furnace into which reduced iron is charged, and a reduction furnace providing the reduced iron, and connected to the melting gasification furnace. A coal briquette that is rapidly heated, and includes a raw coal and a rice powder binder.

The damaged starch content in the rice powder binder may be greater than 5% by weight.

The rice powder binder may be greater than 3% by weight, based on 100% by weight of the total seonghyeongtan.

The starch content in the rice powder binder may be 85 to 95% by weight based on dry weight.

The amylose content in the starch may be 12 to 24% by weight.

A method for manufacturing coal briquettes according to an embodiment of the present invention is a molten iron manufacturing apparatus including a melting gasification furnace into which reduced iron is charged, and a reduction furnace connected to the melting gasification furnace and providing the reduced iron, the dome portion of the melting gasification furnace It is a method of manufacturing coal briquettes that are charged and heated rapidly.

The seonghyeongtan manufacturing method includes: preparing a raw coal, preparing a rice powder binder by adjusting the damaged starch content in rice powder to more than 5% by weight, and preparing a blended coal by mixing the raw coal and the rice powder binder , Gelatinizing the binder in the blended coal, and molding the blended coal.

The step of preparing a blended coal by mixing the raw coal and the rice powder binder

With respect to 100% by weight of the total blended coal, the rice powder binder may be mixed in an amount greater than 3% by weight.

The manufacturing of the rice powder binder may include drying the rice to adjust the moisture content, and pulverizing the rice whose moisture content is adjusted to adjust the particle size.

The step of controlling the moisture content of the rice may be controlling the moisture content to 10% by weight or less.

Adjusting the particle size of the rice powder may be pulverizing so that the average particle size of the rice powder is 20 to 100 μm.

The rice powder binder prepared in the step of preparing the rice powder binder may satisfy the following calculation formula 1.

[Calculation 1] Moisture content of dried rice (wt%) / Damaged starch content in the prepared rice powder binder (wt%) <0.92

The rice powder binder prepared in the step of preparing the rice powder binder may satisfy the following calculation formula 2.

[Calculation 2] The particle size of the prepared rice powder binder (㎛) / the content of damaged starch in the prepared rice powder binder (% by weight) <10

The rice powder binder prepared in the step of preparing the rice powder binder may have a maximum gelatinization viscosity of 300 cP or more at 30 to 95°C.

The step of gelatinizing the binder in the blended coal may be heat treatment by applying heat and moisture to the blended coal.

The heat treatment step may be performed for 5 to 30 minutes at a temperature of 70 to 150 °C.

According to an embodiment of the present invention, there is provided a coal briquette having excellent cold strength and hot strength by using rice powder as a binder, and a method of manufacturing the same.

Specifically, by controlling the damaged starch content of the rice powder binder, it is possible to improve the viscosity of the binder and secure the strength of the coal briquettes.

Specific conditions for controlling the damaged starch content of the rice powder binder are provided.

Diversity of the supply and demand of binder raw materials can be secured, and the binder can be manufactured by a simple method, thereby reducing the cost of manufacturing coal briquettes.

1 shows the starch content of each of corn starch, rice powder, corn fine powder, and corn powder.
2 is a schematic diagram of a method for manufacturing coal briquettes according to an embodiment of the present invention.
3 is a 5000 magnification SEM image of intact starch.
4 is a 5000 magnification SEM image of damaged starch.
5 is a 5000 magnification SEM image of corn starch.
6 is a 5000 magnification SEM image of rice powder having an average particle size of 81 μm.
7 is a 5000 magnification SEM image of rice powder having an average particle size of 28 μm.
8 is a schematic diagram of an apparatus for manufacturing coal briquettes according to an embodiment of the present invention.
9 is a schematic diagram of an apparatus for manufacturing molten iron.
10 is a schematic diagram of an apparatus for manufacturing molten iron.
11 is a graph of starch gelatinization properties.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, and the present invention is not limited thereby, and the present invention is only defined by the scope of the claims to be described later.

The terminology used herein is only for referring to specific embodiments and is not intended to limit the present invention. Singular forms as used herein also include plural forms unless the phrases clearly indicate the opposite. As used in the specification, the meaning of "comprising" specifies a specific characteristic, region, integer, step, action, element and/or component, and the presence of another characteristic, region, integer, step, action, element and/or component, or It does not exclude additions.

Damaged starch in the present invention means a starch with damage to the particle surface. Such damage to the surface of the starch particles may be caused by mechanical damage to the surface of the starch particles during the milling process, and the damaged starch has a property of increasing moisture absorption and being easily gelatinized by low temperature and heat.

Although not defined differently, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms defined in a commonly used dictionary are additionally interpreted as having a meaning consistent with the related technical literature and the presently disclosed content, and are not interpreted in an ideal or very formal meaning unless defined.

The present invention relates to a coal briquette for manufacturing molten iron requiring high strength, and a method for manufacturing the same, and not using pure starch as a binder, but pulverizing rice and using rice powder as a binder, and a briquette in which pure corn starch is applied as a binder. It relates to coal briquettes capable of securing equal or higher strength and quality, and a method of manufacturing the same.

Specifically, in order to use rice powder with a low starch content as a binder, by controlling the content of damaged starch in the rice powder by controlling the moisture content and the pulverized particle size, a rice powder binder that is easy to develop viscosity is prepared and used as a binder. Thus, it relates to a coal briquette for manufacturing molten iron having sufficient strength, and a method of manufacturing the same.

In the case of the binder used in the existing coal briquettes for manufacturing molten iron, corn starch containing more than 99% starch on a dry basis is mainly used. However, in order to manufacture corn starch, complicated processes such as selection (removal of foreign matter), immersion (acid treatment), pulverization, germ separation, octopus separation, and gluten separation require large-scale equipment and increase manufacturing cost.

In the case of rice, it may not be used for food due to long-term storage, or it may have to be disposed of due to heavy metal contamination, and there are cases where it is generated as a by-product during the milling process, such as rice bran, so it is highly likely to be supplied at a low price. .

However, since rice has a lower starch content than pure starch, there is a problem in that it is difficult to secure a sufficient level of seonghyeongtan strength when used as a binder for seonghyeongtan for molten iron production.

In the present invention, the rice powder binder is manufactured by simply pulverizing the rice, thereby simplifying the process required for manufacturing the binder. In addition, the rice used at this time can be stored for a long time or contaminated with heavy metals, and thus, by using raw materials that are not edible, the cost of the binder used for seonghyeongtan can be reduced, and the supply and demand can be stabilized through the diversification of raw materials. In addition, the strength of the coal briquettes can be secured by changing the properties of the rice powder to facilitate the expression of adhesive force.

When rice is pulverized, the starch particles contained in the rice are physically damaged depending on the moisture content, grinding method, and particle size of the rice, and the damage to the starch particles changes the gelatinization properties of the starch. In the present invention, by controlling the content of damaged starch in the rice powder according to the pulverization particle size and moisture content of the rice powder, it is possible to improve the performance as a binder and secure the strength of the coal briquettes.

Coal briquettes

The seonghyeongtan according to an embodiment of the present invention includes a raw coal and a rice powder binder. The damaged starch content in the rice powder binder may be greater than 5% by weight.

Damaged starch content can increase the moisture absorption rate of starch, thereby increasing adhesion.

Starch does not dissolve in cold water, but in hot water it dissolves in a gel form. It is not simply dissolved like sugar or salt, but undergoes a process called alpha (α) or gelatinization. Starch originally had a semi-crystalline structure. When starch is put in hot water, water penetrates through the starch particles, causing the starch particles to swell, eventually destroying the starch's semi-crystalline structure. At this time, the amylose molecules trapped come out of the starch particles, and as these amylose molecules are connected to each other, the viscosity of the starch solution increases and becomes sticky like a glue, which is called gelatinization. It may contain more than 5% by weight of damaged starch content in the rice powder binder. Specifically, the content of the damaged starch is more than 5% by weight, and 30% by weight or less, more than 5% by weight and 25% by weight or less, more than 5% by weight and 20% by weight or less, 8 to 20% by weight, 10 to 20% by weight, It may be 11 to 20% by weight, 14 to 20% by weight, and 17 to 20% by weight. In this case, despite the lower starch content compared to the conventional corn starch binder, excellent briquette strength can be secured. The higher the content of the damaged starch in the rice powder binder is, the better, but when it contains more than 5% by weight, strength similar to or higher than that of the conventional binder can be secured. If the damaged starch content is too low, the strength of the coal briquettes to which it is applied may be lowered, and if the damaged starch content is too high, it may be advantageous to secure the strength of the briquettes, but the cost of manufacturing the binder may increase, thereby lowering the economy.

The rice powder binder may be greater than 3% by weight, based on 100% by weight of the total seonghyeongtan. If the above range is satisfied, the strength of the coal briquettes can be secured. As the content of the binder increases, the strength of the coal briquettes may be improved, but the cost required for the binder may increase, resulting in a lower economical efficiency. If the amount of the rice powder binder is too small, the strength of the coal briquettes may decrease. Specifically, it may be more than 3% by weight and 10% by weight or less, 4 to 10% by weight, 4 to 8% by weight, or 4 to 7% by weight.

The starch content in the rice powder binder may be 85 to 95% by weight based on dry weight.

The amylose content in the starch may be 12% by weight or more. Specifically, it may be 12 to 24% by weight, 13 to 18% by weight, 13 to 17% by weight, or 14 to 16% by weight. In general, the higher the amylose content in the starch, the better the gelatinization and the adhesive strength may increase. However, the starch content and the amylose content in the starch may vary depending on the type of grain, the variety of rice, or whether it is improved, and the starch content in the rice powder binder is 85% by weight or more in terms of diversity in the supply and demand of binder raw materials, and If the amylose content is 12% by weight or more, the strength of the coal briquettes can be secured. If the starch content in the binder or the amylose content in the starch is too small, the strength of coal briquettes may decrease due to insufficient adhesion.

The starch content or the amylose content may vary depending on the type of grain as a binder raw material.

In the case of rice, the amylose content may vary depending on the variety or improvement. Journal Korean J. Food Cookery Sci. Vol. 29, No. Table 1 shows the approximate contents of amylose in major varieties published in 6 (2013).

Amylose content (% by weight) Hopyeong 13.61 Ilmi 14.45 Koshihikari 13.16 Hitomebore 13.55 Beauty (Mipum) 16.53

However, this is for aiding understanding of the present invention, and does not mean that the variety or amylose content of the rice of the present invention is limited thereto.

The raw coal may be pulverized coal. As the pulverized coal, raw materials containing carbon such as bituminous coal, subbituminous coal, anthracite, and coke may be used.

1 is a measurement of starch content in corn starch, rice powder, corn fine powder, and corn powder. In the case of rice powder, corn flour, and corn powder, it can be seen that the starch content is lower than that of corn starch. The higher the starch content, the greater the adhesive strength of the binder. Corn starch used as a conventional binder has a very high starch content, with a starch content of 99% by weight or more, but as shown in FIG. 1, rice powder has a problem that is difficult to apply as a binder because the starch content is lower than that of corn starch. .

In the present invention, although the starch content of the rice powder is relatively low, the content of damaged starch in the rice powder is increased, the gelatinization properties of the starch are changed, and the adhesiveness of the binder is improved, as a result, the strength of the coal briquettes is improved.

The amount of amylose in the starch may vary depending on the variety of rice, and as the amount of amylose in the starch increases, the adhesive strength of the binder may increase. When the amylose content in the starch is satisfied, the rice powder binder can secure sufficient adhesive strength by adjusting the damaged starch content, and the seonghyeongtan strength can be secured.

The moisture content in the coal briquettes may be 5 to 10% by weight. If the moisture content is too small, the strength of the coal briquettes may decrease, and if the moisture content is too high, the efficiency may decrease when used for manufacturing molten iron.

Since rice powder, not corn starch, is used in the coal briquettes according to an embodiment of the present invention, a difference may also appear in the contents of amylose and amylopectin in the separated starch binder. Corn starch generally has an amylose content of 25 to 31%, whereas rice powder has a lower amylose content than corn starch. In the case of the short-grained rice, the amylose content has a level of 12 to 24% by weight, specifically 13 to 18% by weight. By analyzing the amylose content of the starch binder separated from the coal briquettes, it is possible to distinguish between the coal briquettes using corn starch as the binder and the briquettes using rice powder as the binder.

Specifically, the content of damaged starch in the manufactured coal briquettes can be determined by the following method. The coal and starch are physically separated, the starch content is measured, and the damaged starch content in the separated starch is measured.

The starch content can be measured using an enzymatic digestion method. First, the starch and coal in the coal briquettes are treated with a starch decomposing enzyme to decompose the starch, and then separated through a 5A to 5C filter to check the total starch content.

Next, to measure the damaged starch content in the starch, the starch separated from coal is decomposed into maltodextrin using Fungal α-amylase, and then the damaged starch content is measured using a damaged starch content measurement kit. By measuring, it is possible to determine the damaged starch content of the total starch content of the starch binder used in the coal briquettes.

How to make coal briquettes

It relates to a method for manufacturing coal briquettes that are charged to the dome of the melting gasification furnace and rapidly heated in a molten iron manufacturing apparatus including a melting gasifier into which reduced iron is charged, and a reduction furnace connected to the melting gasification furnace and providing the reduced iron. .

2 schematically shows the sequence of a method for manufacturing coal briquettes according to an embodiment of the present invention.

The method of manufacturing coal briquettes according to an embodiment of the present invention includes: i) preparing a raw coal (S10), ii) preparing a rice powder binder by adjusting the damaged starch content in the rice powder to more than 5% by weight (S20), iii) mixing the raw coal and the rice powder binder to prepare a blended coal (S30), iv) gelatinizing the binder in the blended coal (S40), and v) molding the blended coal (S50). Includes.

The present invention includes the step (S20) of preparing a rice powder binder by adjusting the damaged starch content in the rice powder, thereby providing a method of manufacturing high-strength coal briquettes using rice having a low starch content as a binder.

Specifically, the step of preparing a rice powder binder by adjusting the damaged starch content in the rice powder (S20) includes drying the rice to adjust the moisture content, and pulverizing the rice whose moisture content is adjusted to adjust the particle size. Can include.

In addition, it may include a step (S40) of gelatinizing the binder in the blended coal after the step of manufacturing the blended coal (S30).

First, in the step S10 of preparing the raw coal, pulverized coal may be used as the raw coal. As pulverized coal, raw materials containing carbon such as bituminous coal, subbituminous coal, anthracite, and coke can be used. The particle size of the pulverized coal can be adjusted to 4 mm or less. When the particle size of the pulverized coal is satisfied, the blendability, uniformity, and handling properties with the binder may be improved, and the strength of the coal briquettes may be improved.

Then, a step (S20) of preparing a rice powder binder by adjusting the damaged starch content in the rice powder to more than 5% by weight is performed. Specifically, the content of the damaged starch is more than 5% by weight, and 30% by weight or less, more than 5% by weight and 25% by weight or less, more than 5% by weight and 20% by weight or less, 8 to 20% by weight, 10 to 20% by weight, It may be 11 to 20% by weight, 14 to 20% by weight, and 17 to 20% by weight.

The content of damaged starch in the rice powder binder may be adjusted according to the moisture content and grinding temperature of the rice before grinding, the grinding particle size, and the type of grinder. Damaged starch can be generated during the pulverization of grains, and by controlling the content of damaged starch, the temperature at which viscosity develops during the seonghyeongtan manufacturing process is lowered, and the impregnation performance that absorbs water is improved, thereby improving water binding strength. It is increased, the enthalpy for starch gelatinization is lowered, and the function as a seonghyeongtan binder can be improved.

Therefore, the higher the damaged starch content in the rice powder is, the more advantageous it is in terms of adhesion and briquette strength of the binder. However, in order to increase the damaged starch content, the cost of manufacturing the rice powder binder may increase, thereby reducing economic feasibility.

Figure 3 shows the SEM image (5000 magnification) of the intact starch, Figure 4 shows the SEM image (5000 magnification) of the damaged starch. As shown in FIG. 4, in the case of damaged starch, it means starch in which damage has occurred on the surface of the starch, and the damage that has occurred on the surface of the starch can improve water absorption into the starch. In the case of corn starch having a particle size of 14 μm in FIG. 5, the damaged starch content is only 1%, but in the case of the rice powder binder of FIGS. 6 and 7 prepared according to an embodiment of the present application, the content of damaged starch is 9.9% by weight. , 17.2% by weight, it can be seen that the damaged starch content is remarkably higher despite the larger particle size than corn starch.

Since rice before pulverization is removed from a portion with a small starch content in the outer shell according to the degree of polishing, the degree of polishing of the rice before pulverization may affect the composition of the rice powder binder to be produced. Specifically, rice milled for 9 to 12 minutes may be used. In an embodiment of the present invention to be described later, a rice powder binder was prepared using rice that has been polished for about 12 minutes.

The step of manufacturing a rice powder binder by adjusting the damaged starch content to more than 5% by weight (S20) may include drying the rice to adjust the moisture content, and pulverizing the rice to adjust the particle size.

In the step of controlling the moisture content by drying the rice, the moisture content may be adjusted to 10% by weight or less. Depending on the moisture content of the rice, the damaged starch content of the rice powder binder produced in the pulverization process changes, which greatly affects the quality of the binder.

If the moisture content is too high, the content of damaged starch in the rice powder binder obtained by the subsequent pulverization process may decrease. As the moisture content decreases, the damaged starch content may increase, but economic efficiency may decrease due to an increase in the cost required for the process, and the risk of fire may increase during pulverization. Specifically, the moisture content of rice may be 4 to 10% by weight or 5 to 10% by weight. The drying for controlling the moisture content may be by hot air or natural drying, and is not limited to such a drying method, and the moisture content may be adjusted by an appropriate drying method if necessary. In the examples of the present invention described later, moisture was controlled by drying in an oven at 80°C. The lower the moisture content at this time, the better, but it was divided into 5%, 10%, and 14% (undried) in consideration of the risk of fire or increased drying cost during pulverization.

Next, the step of pulverizing the rice to adjust the particle size may be adjusting the particle size of the rice powder by pulverizing the rice powder so that the average particle size of the rice powder becomes 20 to 100 μm. The content of damaged starch in the powder may increase in the process of adjusting the particle size by pulverizing the rice. If the pulverized particle size is too small, the likelihood of loss due to dust collection during the seonghyeongtan manufacturing process increases, and if it is too large, the dispersion degree of the binder decreases, or the amount of damaged starch in the prepared rice powder binder may decrease, resulting in a decrease in adhesion.

Grinding can be performed using a general grinder such as a pin mill, blade mill, or fine mill, and a hammer mill or roll mill before fine grinding. Coarse grinding can be performed through (Roll Mill). The pulverization may be performed by dry pulverization, and it is possible to simplify and simplify the manufacturing process in that a complex process condition control is not required, and the content of damaged starch can be simply controlled by dry pulverization. In the case of dry grinding, there is an advantage of not changing the moisture content of the rice adjusted in the previous step.

In the embodiment of the present invention described later, rice powder having an average particle size of 30 µm, 70 µm, 100 µm, and 200 µm was prepared to check the binder performance in order to find a range in which the quality of the coal briquettes is easily secured and the loss of dust collection is not large I did.

The rice powder binder prepared in the step (S20) of preparing the rice powder binder may have a starch content of 85 to 95 wt% based on a dry weight, and an amylose content in the starch may be 12 to 24 wt%. If the above range is satisfied, high-strength coal briquettes may be manufactured by using rice powder as a binder. Specifically, the amylose content in the starch may be 12 to 24% by weight, 12 to 24% by weight, 12 to 20% by weight, 12 to 18% by weight, 13 to 16% by weight, or 14 to 16% by weight. The rice powder binder, which satisfies the starch content and the amylose content in the starch, can secure the strength of coal briquettes when applied as a binder even if the amount of amylose is smaller than that of the corn starch binder. This is because the rice powder binder contains more than a certain level of damaged starch.

In the step of preparing the rice powder binder, the prepared rice powder binder may satisfy the following calculation formula 1.

[Calculation 1]

Water content of dried rice (% by weight) / Damaged starch content in the prepared rice powder binder (% by weight) <0.92

If the above range is satisfied, seonghyeongtan having a level similar to or higher than that of seonghyeongtan using a conventional corn starch binder can be manufactured.

In the step of preparing the rice powder binder, the prepared rice powder binder may satisfy the following calculation formula 2.

[Calculation 2]

Prepared rice powder binder particle size (㎛) / Damaged starch content in the prepared rice powder binder (% by weight) <10

If the above range is satisfied, seonghyeongtan having a level similar to or higher than that of seonghyeongtan using a conventional corn starch binder can be manufactured.

에서 농도 8% 수용액 상태에서의 최대 호화 점도가 300 cP 이상인 것일 수 있다. 구체적으로, 30 내지 95℃에서 최대 호화 점도는 350 cP 이상, 350 내지 1000 cP, 350 내지 800 cP, 400 내지 800 cP, 400 내지 764 cP, 600 내지 800 cP, 700 내지 800 cP, 760 내지 800cP, 또는 700cP 이상일 수 있다. 상기 최대 호화 점도 범위를 만족하는 경우 성형탄 강도를 확보할 수 있다. 상기 범위보다 낮은 경우 성형탄 강도가 저하되거나, 성형탄 제조시 필요한 바인더 함량 증가로 제조 비용이 상승할 수 있다. 최대 호화 점도는 높을수록 유리하나, 최대 호화 점도가 너무 높은 경우 바인더 제조 공정 비용이 상승하여 경제성이 저하되거나, 장치에의 부착 문제등이 발생할 수 있다. The rice powder binder prepared in the step (S20) of preparing the rice powder binder is 30 to 95

The maximum gelatinization viscosity in an aqueous solution of 8% concentration may be 300 cP or more. Specifically, the maximum gelatinization viscosity at 30 to 95°C is 350 cP or more, 350 to 1000 cP, 350 to 800 cP, 400 to 800 cP, 400 to 764 cP, 600 to 800 cP, 700 to 800 cP, 760 to 800 cP, Or it may be 700 cP or more. If the maximum gelatinization viscosity range is satisfied, the seonghyeongtan strength can be secured. If it is lower than the above range, the strength of the coal briquettes may decrease, or the manufacturing cost may increase due to an increase in the amount of binder required for manufacturing the coal briquettes. The higher the maximum gelatinization viscosity is, the more advantageous it is, but if the maximum gelatinization viscosity is too high, the cost of the binder manufacturing process rises, resulting in a decrease in economic efficiency, or a problem of adhesion to the device.

일 수 있다. 구체적으로 호화 개시온도가 40 내지 70

, 40 내지 68.2

, 40 내지 60

, 또는 50 내지 60

일 수 있다. The rice powder binder prepared in the step of preparing the rice powder binder has a gelatinization start temperature of 40 to 75

Can be Specifically, the gelatinization initiation temperature is 40 to 70

, 40 to 68.2

, 40 to 60

, Or 50 to 60

Can be

When satisfying the gelatinization initiation temperature range and the maximum gelatinization viscosity range at 30 to 95°C, there is an advantage that a conventional device can be used.

Next, in the step (S30) of preparing a blended coal by mixing the rice powder binder and the raw coal, a binder is added to the pulverized coal according to the determined ratio and then uniformly mixed to prepare a blended coal.

In the step of preparing the blended coal (S30), the rice powder binder may be mixed by adding more than 3% by weight and 7% by weight or less based on 100% by weight of the total blended coal.

If the amount of the binder is too small, the strength of the coal briquettes may decrease, and if the amount of the binder is too large, problems such as sticking to the device may occur in the process of molding the mixture. It can be degraded.

In the step (S30) of preparing the blended coal, other types of binders such as rice powder binder and corn starch may be used together.

Next, the step (S40) of gelatinizing the binder in the blended coal may be performed. The step of gelatinizing the binder in the blended coal may be to increase adhesion through a gelatinization reaction between water and the binder in the blended coal by heat treatment of the blended coal.

The heat treatment may be to apply heat and moisture to the blended coal, or to supply steam to the blended coal.

온도에서 5 내지 30분 동안 수행하는 것일 수 있다. 구체적으로 5 내지 20분 동안 수행하는 것일 수 있다. 상기 범위를 만족하는 경우 쌀 분말 바인더 내의 전분을 효과적으로 호화 시킴으로써, 바인더 점착력을 향상시키고 성형탄 강도를 확보할 수 있다.The heat treatment is 70 to 150

It may be performed for 5 to 30 minutes at temperature. Specifically, it may be performed for 5 to 20 minutes. If the above range is satisfied, the starch in the rice powder binder can be effectively gelatinized, thereby improving binder adhesion and securing the strength of coal briquettes.

Next, a step (S50) of molding the blended coal is performed. The blended coal can be manufactured by charging and pressing the mixture between a pair of rollers, thereby producing a pocket or strip-shaped seonghyeongtan. However, this is only an example of the present invention, and does not mean that it is limited to the above-described molding apparatus and molding form.

After the step of molding the blended coal (S50), the step of drying the molded body may be further performed, and the drying is not limited to a drying method such as natural drying or hot air drying, and may be performed by an appropriate method.

Coal briquette manufacturing equipment

The present invention is an apparatus for manufacturing coal briquettes which is charged to the dome of the melting gasification furnace and rapidly heated in a molten iron manufacturing apparatus including a melting gasification furnace into which reduced iron is charged, and a reduction furnace connected to the melting gasification furnace and providing the reduced iron. It is about.

The apparatus for manufacturing coal briquettes according to an embodiment of the present invention includes a raw coal supply bin 1, a rice supply bin 2, a drying device 3 connected to the rice supply bin 2 and receiving and drying rice, and the A pulverizing device 4 connected to a drying device and pulverizing the dried rice raw material to produce a rice powder binder, a rice powder binder supply bin 5 connected to the pulverizing device and storing a rice powder binder, the raw coal supply bin ( 1) and a mixing device 6 connected to the rice powder binder supply bin 5, respectively, to prepare a compound coal by mixing raw coal and a rice powder binder, and heat treatment by receiving the compound coal from the mixing device 6 The kneader 7 includes a molding device 8 for molding the blended coal.

The kneader 7 may supply heat and moisture.

The kneader 7 has a steam supply pipe connected, and may be supplied with steam from the steam supply pipe to heat-treat the blended coal.

8 schematically shows an apparatus for manufacturing coal briquettes according to an embodiment of the present invention.

As shown in Fig. 8, the coal briquettes manufacturing apparatus 60 includes a raw coal supply bin 1 and a rice supply bin 2 for storing raw coal, a drying device 3 for adjusting an appropriate moisture content, and dried raw materials. A pulverizing device 4 for pulverizing and a rice powder binder supply bin 5 for storing and supplying a rice powder binder, a mixing device 6 for mixing the raw coal and the rice powder binder, and heat and heat to the mixture mixed in the mixer 6 It includes a kneader 7 for supplying moisture to impart adhesiveness, and a molding apparatus 8 for manufacturing coal briquettes by molding the mixed mixture.

The molding apparatus 8 compresses the mixture to produce coal briquettes. For example, the molding apparatus 8 may be provided with a pair of rollers, and a mixture may be charged and compressed between the rollers to manufacture a pocket or strip-shaped coal briquettes.

9 schematically shows a molten iron manufacturing apparatus 100 using coal briquettes manufactured according to the present embodiment. The structure of the apparatus 100 for manufacturing molten iron in FIG. 9 is for illustrative purposes only, and the present invention is not limited thereto. Therefore, the molten iron manufacturing apparatus 100 of FIG. 9 can be modified in various forms.

The molten iron manufacturing apparatus 100 of FIG. 9 includes a melting gasification furnace 10 and a packed bed type reduction furnace 20. In addition, other devices may be included as needed. Iron ore is charged and reduced in the packed bed type reduction furnace 20. The iron ore charged in the packed bed type reduction furnace 20 is made of reduced iron while passing through the packed bed type reduction furnace 20 after being pre-dried. The packed bed type reduction furnace 20 is a packed bed type reduction furnace, and receives reducing gas from the melting gasifier 10 to form a packed bed therein.

Since the coal briquettes manufactured according to the present embodiment are charged into the melter gasifier 10, a coal filling layer is formed inside the melter gasifier 10. A dome 101 is formed on the upper part of the melter gasifier 10. That is, a wider space is formed than other parts of the melter gasifier 10, and there is a high-temperature reducing gas. Therefore, the coal briquettes charged into the dome 101 by the high-temperature reducing gas are converted into char by a pyrolysis reaction. The char produced by the pyrolysis reaction of the coal briquettes moves to the lower portion of the melting gasification furnace 10 and reacts exothermicly with oxygen supplied through the air outlet 30. As a result, coal briquettes can be used as a heat source for maintaining the melting gasifier 10 at a high temperature. On the other hand, since char provides air permeability, a large amount of gas generated in the lower part of the melting gasifier 10 and reduced iron supplied from the packed-bed reduction furnace 20 make the coal-filled bed in the melter gasifier 10 easier and more uniform. Can pass.

In addition to the above-described coal briquettes, bulk carbon material or coke may be charged into the melter gasifier 10 as necessary. An air vent 30 is installed on the outer wall of the melter gasifier 10 to inject oxygen. Oxygen is blown into the coal-filled bed to form a combustion zone. Coal briquettes can be burned in a combustion zone to generate reducing gas.

10 schematically shows an apparatus 200 for manufacturing molten iron using coal briquettes manufactured according to the present embodiment. The structure of the apparatus 200 for manufacturing molten iron of FIG. 10 is for illustrative purposes only, and the present invention is not limited thereto. Therefore, the molten iron manufacturing apparatus 200 of FIG. 10 can be modified in various forms. Since the structure of the molten iron manufacturing apparatus 200 of FIG. 10 is similar to that of the molten iron manufacturing apparatus 100 of FIG. 9, the same reference numerals are used for the same parts, and a detailed description thereof is omitted.

As shown in FIG. 10, the molten iron manufacturing apparatus 200 includes a melt gasification furnace 10, a fluidized bed reduction furnace 22, a reduced iron compression device 40, and a compressed reduced iron storage tank 50. Here, the compressed reduced iron storage tank 50 may be omitted.

The manufactured coal briquettes are charged into the melting gasification furnace 10. Here, the coal briquettes generate a reducing gas in the melter gasifier 10, and the generated reducing gas is supplied to the fluidized bed type reduction furnace 22. Powdered iron ore is supplied to a plurality of reduction furnaces 22 having a fluidized bed, and is made of reduced iron while flowing by the reducing gas supplied from the melting gasifier 10 to the fluidized bed type reduction furnace 22. The reduced iron is compressed by the reduced iron compression device 40 and then stored in the compressed reduced iron storage tank 50. The compressed reduced iron is charged from the compressed reduced iron storage tank 50 into the melting gasification furnace 10 together with coal briquettes and melted in the melting gasification furnace 10. Since the coal briquettes are supplied to the melting gasification furnace 10 and transformed into char with ventilation, a large amount of gas and compressed reduced iron generated in the lower portion of the melting gasification furnace 10 make the coal-filled layer in the melting gasification furnace 10 easier and more uniform. It can provide high-quality molten iron by passing through it.

Hereinafter, preferred examples and comparative examples of the present invention will be described. However, the following examples are only preferred examples of the present invention, and the present invention is not limited to the following examples.

Evaluation Example 1-Evaluation of binder gelatinization properties

(Corn starch (CS): Comparative Example 1 (CS)) As a comparative example, powdered corn starch was used. The corn starch is of high purity with a starch content of 99% or more on a dry basis. 5 shows a 5000 magnification SEM image of corn starch (CS). The measured average particle size of the corn starch binder (CS) was 14 μm, and the damaged starch content in the corn starch binder (CS) was approximately 1.0% by weight.

(Rice powder (RP): Experimental Example 1-1 (RP70), Experimental Example 1-2 (RP500)) Rice that was polished for about 12 minutes was used, the starch content was approximately 90% by weight, and the amylose content was approximately 15 Domestically produced single grains of weight% were used. After the moisture content was adjusted to 10% by weight or less through the drying process, the particles were pulverized to 70 mesh (Experimental Example 1-1: RP70, 81㎛) and 500 mesh (Experimental Example 1-2: RP500, 28㎛). Adjusted.

6 is a 5000 magnification SEM image of the rice powder binder Experimental Example 1-1 (RP70) prepared according to an embodiment of the present invention, and FIG. 7 is a 5000 magnification of the prepared rice powder binder Experimental Example 1-2 (RP500) This is an SEM image.

The prepared rice powder binder Experimental Example 1-1 (RP70) and Experimental Example 1-2 (RP500) had a damaged starch content of 9.9% by weight and 17.2% by weight, respectively. In the rice powder binder prepared according to an embodiment of the present invention, it can be seen that the smaller the particle size, the higher the damaged starch content. In addition, it can be seen that even though the particle size is larger than that of the corn starch of Comparative Example 1 (CS), it has a higher content of damaged starch,

(Method of measuring damaged starch content) The prepared rice powder binder was measured using a Megazyme assay kit using Fungal α-amylase at 40°C. Specifically, according to the method of measuring damaged starch provided by Megazyme, 50 Unit/ml of Fungal α-amylase was added to 100 mg of a sample containing damaged starch to convert the damaged starch with maltodextrins at 40°C. Let it react for 10 minutes. Next, dilute sulfuric acid is added to terminate the reaction. After separating this through centrifugation, 0.1 ml of amyloglucosidase solution was reacted at 40° C. for 10 minutes to 0.1 ml of the supernatant on the surface, and then 4.0 ml of GOPOD additive solution was added and reacted for 20 minutes. . Put this in a spectrophotometer, read the absorbance at 510 nm, and calculate the damaged starch content from the value compared with the absorbance of the standard sample.

(Method of measuring maximum gelatinization viscosity) The maximum gelatinization viscosity of the binder was measured using Brabender's Micro Visco-Amylo-Graph®-U. The binder was made into an 8% aqueous solution and heated from 30℃ to 5℃ per minute. The maximum measured value of the viscosity until reaching the maximum temperature of 95°C was taken as the maximum viscosity.

When the maximum gelatinization viscosity of starch is too low, the bonding strength to the pulverized coal decreases, and the strength of the coal briquettes may decrease.

Table 2 shows the components, content, particle size, and density of the binder used in the experimental and comparative examples.

Binder type Corn starch Rice powder Comparative Example 1-1
(CS) Experimental Example 1-1
(RP70) Experimental Example 1-2
(RP500) Moisture (%, 110℃, 3hr) 9.6 10 4.5 Starch content (% by weight) Dry base 99.6 90.7 90.7 (% by weight) Wet base 90.1 81.5 86.0 Damaged starch content (% by weight) 1.0 9.9 17.2 Starch component Amylose (% by weight) 25.1 15.9 14.6 Amylopectin (% by weight) 74.9 84.1 85.4 Granularity
(㎛) Dx (10%) 7.9 11.5 6.26 Dx (50%) 14.2 61.3 22.1 Dx (90%) 21.9 181 51.9 Average particle size 14.3 84 28 density
(g/cc) Bulk Density 0.498 0.637 0.531 Tap Density 0.701 0.887 0.807 Compression degree (%) 29.0 28.1 34.2 Wet
analysis
(weight%) K ₂ O 0.0105 0.19 0.17 Na ₂ O 0.0243 0.011 0.011

11 is a comparative example 1 corn starch binder (CS) of Table 2 and the gelatinization properties were tested using the rice powder binders of Experimental Example 1-1 (RP70) and Experimental Example 1-2 (RP500) with different pulverized particle sizes. .

11, it can be seen that all the experimental examples and comparative examples satisfy the range of 200 to 2000 cPs at 30 to 95°C. More specifically, in Experimental Example 1-1 (RP70) and Experimental Example 1-2 (RP500), it was confirmed that the maximum gelatinization viscosity at 30 to 95°C was 400 cP and 764 cP, respectively.

Experimental Example 1-1 (RP70) was found to have a slightly higher gelatinization initiation temperature and a slightly lower maximum gelatinization viscosity than that of Comparative Example 1 corn starch binder (CS). However, it can be seen that even in the case of Experimental Example 1-1 (RP70) through Evaluation Example 2 to be described later, it is possible to secure the viscosity necessary for application to the seonghyeongtan binder.

에서 52.3

로 낮아지고, 최대 호화 점도가 590cPs에서 764cPs로 증가한 것을 확인할 수 있다. 이는 성형탄에 바인더로서 적용시 충분한 점도를 확보할 수 있으며, 이를 바인더로 적용시 상대적으로 낮은 온도에서 호화시키는 경우에도 충분한 점도를 확보할 수 있는 바, 성형탄 제조 공정상 이점이 될 수 있다. In the case of Experimental Example 1-2 (RP500), the gelatinization initiation temperature compared to Comparative Example 1 corn starch (CS) was 68.2

52.3 in

And the maximum gelatinization viscosity increased from 590 cPs to 764 cPs. When applied as a binder to the seonghyeongtan, sufficient viscosity can be secured, and when applied as a binder, a sufficient viscosity can be secured even when gelatinized at a relatively low temperature, which can be an advantage in the seonghyeongtan manufacturing process.

In addition, it can be seen from the above experimental results that starch gelatinization properties may vary depending on the pulverized particle size.

Evaluation Example 2-Evaluation of cold strength of coal briquettes according to damaged starch content

(Production of seonghyeongtan) Prepare a blended coal by mixing pulverized coal of 3.4mm or less and a rice powder binder. As the pulverized coal, strong-viscous coal, non-viscous coal, and powder coke were mixed and used. Rice powder containing 5 to 20% by weight of damaged starch as a binder by drying short-grained domestic rice polished for about 12 minutes in an oven for a certain period of time to adjust the moisture content, and then pulverizing it to a certain particle size using a grinder. Was used to prepare a binder. Table 3 shows the specific conditions of the binder used.

The particle size of the rice powder was measured using a HELOS paticle size analyzer of Sympatec GmbH.

Damaged starch content of rice powder was measured in the same manner as described in Evaluation Example 1 using a Megazyme assay kit using Fungal α-amylase at 40°C.

Next, the mixture was put into a kneader and heat was applied from the outside so that the moisture and the binder dispersed in the blended coal were gelatinized to increase the adhesive strength. At a kneader temperature of 150 DEG C, the residence time was kept constant at 15 minutes.

Next, the uniformly mixed mixture was charged between a pair of rolls to prepare coal briquettes. In this case, a pair of rolls pressed the mixture at a pressure of 20 kN/cm to produce a pillow-shaped seonghyeongtan of 64.5 mm × 25.4 mm × 19.1 mm. The prepared coal briquettes were stored at room temperature for 1 hour and then their strength was measured.

Since the detailed manufacturing process of the remaining coal briquettes can be easily understood by those of ordinary skill in the art to which the present invention pertains, a detailed description thereof will be omitted.

(Experimental Example 2-1) After drying the rice to a moisture content of 5% by weight, a rice powder binder having a particle size of about 30 μm was prepared, and 4.5% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal, and then seonghyeongtan was prepared in the manner described above. I did.

(Experimental Example 2-2) After drying the rice to a moisture content of 10% by weight, a rice powder binder having a particle size of about 30 μm was prepared, and 4.5% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal, and then seonghyeongtan was prepared in the manner described above. I did.

(Experimental Example 2-3) After drying the rice to a moisture content of 5%, a rice powder binder having a particle size of about 70 μm was prepared, and 4.5% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal, and then seonghyeongtan was prepared in the manner described above. .

(Experimental Example 2-4) After drying the rice to a moisture content of 10%, a rice powder binder having a particle size of about 70 μm was prepared, and 4.5% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal, and then seonghyeongtan was prepared in the manner described above. . (Experimental Example 2-5) A rice powder binder having an average particle size of 96 μm was prepared by drying so that the moisture content of rice was 5%, and 4.5% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal. Coal briquettes were prepared in the same manner.

(Experimental Example 2-6) After drying the rice to a moisture content of 5%, a rice powder binder having a particle size of 31 μm was prepared, and 8% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal, and then seonghyeongtan was prepared in the manner described above.

(Comparative Example 2-1) After mixing 4.5wt% corn starch in the form of powder based on 100% by weight of the blended coal, seonghyeongtan was prepared in the manner described above. (Comparative Example 2-2) A rice powder binder having an average particle size of 193 μm was prepared by drying so that the moisture content of the rice was 5% by weight, and 4.5% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal, Coal briquettes were manufactured in the manner described above.

(Comparative Example 2-3) After drying the rice to a moisture content of 5% by weight, a rice powder binder having an average particle size of 31 μm was prepared, and 3% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal, and then seonghyeongtan was prepared in the manner described above. . (Comparative Example 2-4) A rice powder binder having an average particle size of about 100 μm was prepared in a state where the water content was 14% by weight without drying of the rice, and 4.5% by weight of the rice powder binder was mixed based on 100% by weight of the blended coal. , To prepare coal briquettes in the manner described above.

(Method of measuring the compressive strength of seonghyeongtan) The compressive load of the seonghyeongtan was measured as the maximum load when compressed at a speed of 50mm/min, and was measured as the average value of 20 seonghyeongtan samples.

(Method of measuring the drop strength of seonghyeongtan) The quality of the cold strength was evaluated by measuring the drop strength index of the manufactured seonghyeongtan. The drop strength index was expressed as a weight percentage of a particle size of 20 mm or more after 2 kg of the prepared coal briquettes were freely dropped four times from a height of 5 m.

division Comparative Example 2-1 Comparative Example 2-2 Comparative Example 2-3 Comparative Example 2-4 Experimental Example 2-1 Experimental Example 2-2 Experimental Example 2-3 Experimental Example 2-4 Experimental Example 2-5 Experimental Example 2-6 Total moisture content (%) - 5 5 14 5 10 5 10 5 5 Binder particle size (㎛) 14 193 31 98 28 33 70 69 96 31 Damaged starch (% by weight) One 3 19 5 20 17 14 11 10 19 Binder (% by weight) 4.5 4.5 3.0 4.5 4.5 4.5 4.5 4.5 4.5 8.0 Formula 1 - 1.67 0.26 2.80 0.25 0.59 0.36 0.91 0.50 0.26 Formula 2 14 64.33 1.63 19.60 1.40 1.94 5.00 6.27 9.60 1.63 Compressive strength (kgf) 69 49 45 58 74 69 68 65 67 112 Drop strength (%) 81 63 55 76 85 83 83 81 80 98

In the case of Comparative Example 2-1, the result of the strength test of coal briquettes when using conventional corn starch. In the case of compressive strength of 60kgf or more and dropping strength of 80% or more, seonghyeongtan strength suitable for molten iron production was secured.

In the case of Comparative Example 2-2, rice powder was used as a binder, but when the particle size of the powder was coarse to a level of 200 μm, it was confirmed that the content of the damaged starch was as low as 3% by weight, and the seonghyeongtan strength was not secured.

In the case of Comparative Example 2-3, a high level of damaged starch content was exhibited through sufficient drying and pulverization, but it was confirmed that the strength of the briquettes was not secured because the amount of the binder used was too small as 3% by weight.

In the case of Comparative Example 2-4, the average particle size of the rice powder was 98㎛, but when the water content was pulverized in a high state of 14% by weight, the content of damaged starch was as low as 5% by weight, and it was confirmed that the standard briquette strength was not satisfied. I can.

In the case of Experimental Example 2-1 of the present invention, rice powder having an average particle size of 28 μm was prepared through pulverization after drying the rice as a raw material before pulverization to lower the moisture content, and 4.5% by weight of this was mixed. In this case, even though the rice powder had a lower starch content than corn starch, it was possible to secure a higher strength of coal briquettes compared to Comparative Example 1.

By comparing Experimental Examples 2-1 and 2-2, and Experimental Examples 2-3 and 2-4, the effect of the moisture content before pulverization can be confirmed at a similar grain size of rice powder. In both cases, even if they have the same pulverization particle size, it can be seen that when pulverization is performed in a low moisture content state, the content of damaged starch increases and the strength of the coal briquettes increases compared to the same pulverization particle size.

Experimental Example 2-5 has a large particle size of the rice powder, but if the damaged starch content is increased compared to Comparative Example 2-4 through drying before grinding, a higher level of strength can be secured even at the same binder blending ratio.

By comparing Experimental Example 2-1 and Experimental Example 2-6, the seonghyeongtan strength according to the binder content can be confirmed. In the case of Experimental Example 2-6, it is possible to manufacture coal briquettes having significantly improved strength. However, since approximately twice the amount of the binder is used as compared to Experimental Example 2-1 having similar conditions, the cost of the binder may increase.

Formula 1 is an equation showing the relationship between the moisture content (% by weight) of dried rice and the content of damaged starch (% by weight) in the prepared rice powder binder under the condition that the binder content in the blended coal is more than 3% by weight.

In the case of Experimental Examples 2-1 to 2-6, it can be seen that the binder content in the blended coal is more than 3% by weight, the value of Calculation 1 is less than 0.92, and sufficient seonghyeongtan strength can be secured. On the other hand, in Experimental Example 2-3, since the binder content is 3% by weight or less, it can be seen that the seonghyeongtan has low strength. In addition, in the case of Experimental Examples 2-1, 2-2, and 2-4, the binder content in the blended coal exceeds 3% by weight, but it can be seen that the value of Formula 1 is 0.92 or more.

Calculation Equation 2 is an equation showing the relationship between the prepared rice powder binder particle size (㎛) and the damaged starch content (wt%) in the prepared rice powder binder under the condition that the binder content in the blended coal is more than 3% by weight.

In the case of Experimental Examples 2-1 to 2-6, it can be seen that the binder content in the blended coal is more than 3% by weight, the value of the formula 2 is less than 10, and sufficient seonghyeongtan strength can be secured. On the other hand, in Experimental Example 2-3, since the binder content is 3% by weight or less, it can be seen that even if the value of Formula 2 is less than 10, the seonghyeongtan has low strength. In addition, in the case of Experimental Examples 2-1, 2-2, and 2-4, the binder content in the blended coal exceeded 3% by weight, but it can be seen that the value of Formula 2 is 10 or more.

The present invention is not limited to the above embodiments, but may be manufactured in a variety of different forms, and those of ordinary skill in the art to which the present invention pertains, other specific forms without changing the technical spirit or essential features of the present invention. It will be appreciated that it can be implemented with. Therefore, it should be understood that the embodiments described above are illustrative and non-limiting in all respects.

1: raw coal supply bin 2: rice supply bin
3: drying device 4: grinding device
5: rice powder binder supply bin 6: mixing device
7: kneader 8: molding device
10: melting gasification furnace 20: packed bed type reduction furnace
22: fluidized bed type reduction furnace 30: windpipe
40: reduced iron compression device 50: compressed reduced iron storage tank
100, 200: molten iron manufacturing equipment

Claims (13)

A melting gasifier into which reduced iron is charged, and
As a coal briquette that is connected to the melting gasification furnace and rapidly heated by being charged to the dome of the melting gasification furnace in a molten iron manufacturing apparatus including a reduction furnace for providing the reduced iron,
Including a raw coal, and a rice powder binder,
Briquettes having a damaged starch content of more than 5% by weight in the rice powder binder.
The method of claim 1,
The rice powder binder is a seonghyeongtan that is more than 3% by weight, based on 100% by weight of the total seonghyeongtan.
The method of claim 1,
The starch content in the rice powder binder is 85 to 95% by weight based on dry weight,
The amylose content in the starch is 12 to 24% by weight of coal briquettes.
A melting gasifier into which reduced iron is charged, and
In the molten iron manufacturing apparatus including a reduction furnace connected to the molten gasification furnace and providing the reduced iron,
As a method of manufacturing coal briquettes charged to the dome of the melting gasifier and heated rapidly,
Preparing raw coal;
Preparing a rice powder binder by adjusting the damaged starch content in the rice powder to more than 5% by weight;
Preparing a blended coal by mixing the raw coal and the rice powder binder;
Gelatinizing a binder in the blended coal; And
Briquette manufacturing method comprising the step of molding the blended coal.
The method of claim 4,
The step of preparing a blended coal by mixing the raw coal and the rice powder binder
A method for producing coal briquettes by mixing more than 3% by weight of the rice powder binder with respect to 100% by weight of the total coal blended.
The method of claim 5,
The step of preparing the rice powder binder
Drying the rice to adjust the moisture content; And
Briquettes manufacturing method comprising the step of adjusting the particle size by pulverizing the water content of the rice is adjusted.
The method of claim 6,
Adjusting the moisture content of the rice
The method of manufacturing coal briquettes to control the moisture content to 10% by weight or less.
The method of claim 6,
Adjusting the particle size of the rice powder
The method for producing coal briquettes is pulverized so that the rice powder has an average particle size of 20 to 100 µm.
The method of claim 6,
In the step of preparing the rice powder binder
The prepared rice powder binder is a method for producing coal briquettes that satisfies the following calculation formula 1.
[Calculation 1]
Water content of dried rice (% by weight) / Damaged starch content in the prepared rice powder binder (% by weight) <0.92
The method of claim 6,
In the step of preparing the rice powder binder
The prepared rice powder binder is a method of manufacturing coal briquettes that satisfies the following calculation formula 2.
[Calculation 2]
Prepared rice powder binder particle size (㎛) / Damaged starch content in the prepared rice powder binder (% by weight) <10
The method of claim 4,
In the step of preparing the rice powder binder
The prepared rice powder binder is a method for producing coal briquettes having a maximum gelatinization viscosity of 300 cP or more at 30 to 95°C.
The method of claim 4,
The step of gelatinizing the binder in the coal briquettes is heat-treated by applying heat and moisture to the coal briquettes manufacturing method.
The method of claim 12,
The heat treatment step
Briquettes manufacturing method that is carried out for 5 to 30 minutes at a temperature of 70 to 150 ℃.

Images