JP2013116964A - Method for producing metallurgical coke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing high-strength metallurgical coke by molding raw material coke including non-caking coal by using a compaction molding method, charging the obtained compaction-molded product into the carbonization chamber of a coke oven and dry-distilling the same.SOLUTION: There is provided the method in which low-volatile non-caking coal (A) containing more than 10% and less than 23% volatile components by mass ratio or high-volatile non-caking coal (B) containing more than 32% volatile components by mass ratio is selected, the relational expression of the coke strength index DIto the blending ratio for each of the low-volatile non-caking coal (A) and the high-volatile non-caking coal (B) is estimated, the blending ratio of the non-caking coal is determined so that the coke strength index DIsatisfies a predetermined value, the coke raw material is adjusted in accordance with the determined blending ratio to obtain the compaction-molded product, and then the obtained compaction-molded product is charged into the coking chamber of the coking oven and dry-distilled.

Description

  The present invention relates to a method for producing metallurgical coke, particularly for metallurgical metal having a step of forming coking raw material coal by a compacting method, and charging and carbonizing the obtained compacted product into a carbonization chamber of a coke oven. The present invention relates to a method for producing coke.

Metallurgical coke, especially coke charged into a blast furnace for iron making, has a role as a reducing agent and a role for maintaining air permeability, in addition to a role as a heat source for reaction in the blast furnace. In particular, the role for maintaining air permeability is important, and it is generally required that the strength index represented by the coke strength index DI ¹⁵⁰ ₁₅ exceeds 80. With the recent increase in the size of blast furnaces and the severer operating conditions, the index is even larger, for example, 84 or more is required.

  Such a metallurgical coke having a high strength index can be produced by using so-called strong caking coal as a main raw material and adding examinations from various viewpoints to its production conditions. Attempts to improve the productivity have also been made, contributing to the reduction of iron manufacturing costs. For example, as a means of increasing the bulk density of the charged coal and improving the productivity and coke quality of the coke oven, instead of the conventional gravity charging method, the coal charging method or stamping method (also called the stamp charge method) ) Has been adopted. Among these, the casting coal charging method is to charge about 10 to 30% of the charging coal in a briquette shape and increase the bulk density of the charging coal, but the rate of increase is 10 It remains at around%.

  On the other hand, in the compacting method represented by the stamping method, the blended coal is compacted into a substantially rectangular parallelepiped shape slightly smaller than the size of the carbonization chamber, and the resulting compacted product is charged into the carbonization chamber of the coke oven and dry-distilled. It is a method to do. In this stamping method, the entire amount of the charged coal is compacted, so the bulk density of the charged coal is increased by about 1.5 times compared to the gravity charging method used in the past, and the coal particles are compressed. In addition, the inter-particle distance is shortened, and the generated coke is densified and the coke strength is improved, and many proposals have been made to further utilize the feature (see Patent Documents 1 to 4).

  However, the recent rise in the steel industry, particularly in emerging countries, has led to an increase in demand for strong caking coal, which is essential for the production of metallurgical coke, and in the future it must be assumed that it will be depleted. I have been invited. For this reason, it has become important to blend and use a low-grade, particularly non-caking coal that does not exhibit softening and melting properties during heating, as a coke raw material.

  In consideration of such a resource situation, proposals have been made to mix and blend non-coking coal with raw coal even in the gravity charging method (see, for example, Patent Document 5). Such a proposal can be diverted even in the stamping charging method. On the other hand, Patent Document 6 states that “a total amount of coke oven charging coal composed of coal having different caking properties is rapidly heated to 300 to 500 ° C., and a coal cake is compacted by using coal in a softening and melting zone as a binder. Discloses a preheating stamping method for coal, which is characterized in that it is charged in a coke oven.

JP 59-38279 A JP 59-126495 A JP 61-106691 A Japanese Patent Laid-Open No. 61-87788 Japanese Patent Laid-Open No. 2007-9016 JP-A-7-109467

  Patent Documents 1-4 describe a method for adjusting blended coal and additives necessary for carrying out the compacting method. However, these patent documents do not teach the use standard of non-coking coal in the compacting method. In particular, non-caking coal does not show softening and melting properties when heated, so the fusion between the non-caking carbonized carbide and the surrounding coke structure is poor, and in order to achieve the target coke strength, It is necessary to specifically determine the blending means of caking coal, particularly the blending ratio. On the other hand, the coal preheating stamping charging method disclosed in Patent Document 6 allows charging 30% of non-slightly caking coal and does not require a new binder. It is necessary to rapidly heat all raw materials including non-slightly caking coal and weak / strong caking coal to be charged to 300 to 500 ° C. in advance. Therefore, when using this means, ancillary facilities such as a hot air drying furnace and a hot air generator are required in addition to the stamping device.

  The present invention forms a blended coal comprising a plurality of coal types including non-caking coal by a compacting method, and the obtained compacted product is charged into a carbonization chamber of a coke oven and subjected to dry distillation. An object is to determine a specific blending ratio of caking coal, and to propose a means capable of producing a high strength metallurgical coke by compacting a blended charcoal containing non-caking coal at room temperature.

In the present invention, a blended coal composed of a plurality of coal types including caking coal and non-caking coal is smaller than the furnace width of the coke oven carbonization chamber, and the other two sides are 0.5 m or more. In producing coke for metallurgy by compacting into a substantially rectangular parallelepiped, and charging and dry-distilling the obtained compacted product into the carbonization chamber of the coke oven,
As the non-caking coal, a low volatile non-caking coal (A) with a dry base volatile content of more than 10% and less than 23% or a high volatile content of a dry base with a volatile content of more than 32%. Selecting non-coking coal (B);
Estimating the relational expression of the coke strength index DI ¹⁵⁰ ₁₅ with respect to the blending ratio of the non-caking coal for each of the low volatile matter non-caking coal (A) and the high volatile content caking coal (B);
The blending ratio of the non-coking coal is determined so that the coke strength index DI ¹⁵⁰ ₁₅ satisfies a predetermined value with respect to the blending amount of the low-volatile non-coking coal (A) and the high volatile non-coking coal (B). Stages,
Adjusting the coke raw material according to the blending ratio of the non-caking coal to obtain a compacted molded product,
The step of charging the compacted product into a carbonization chamber of a coke oven and dry-distilling is sequentially performed.
Here, the coke strength index DI ¹⁵⁰ ₁₅ is 10 kg of lump coke having a particle size of 25 mm or more taken as a test sample according to JISK2151, and the whole amount of coke after rotating the drum 150 is recovered, and the coke weight having a particle size of 15 mm or more. This is the ratio measured.

In the above invention, the compacting is preferably performed so that the density of the compacted product satisfies 1.0 to 1.2 t / m ³ on a dry base. Moreover, it is preferable to determine the blending ratio of non-caking coal so that the coke strength index DI ¹⁵⁰ ₁₅ satisfies 84 or more.

When blending only the low volatile matter non-caking coal (A) as the non-caking coal, the blending ratio of the low volatile matter non-caking coal (A) may satisfy the following formula (1). desirable.
P _A ≦ 0.47 × (VM _L ) ^1.4 (1)
here,
P _A : refers to the blending ratio (mass% on dry base) of low volatile non-coking coal (A),
(Amount of low volatile non-coking coal (A), (t) / (total amount of blended coal (t))) × 100
Means what is required by Here, VM _L : refers to the content ratio of the volatile content of the low volatile matter non-coking coal (A), and refers to the volatile content (mass% on a dry base) determined according to JIS M8812.

In addition, when blending only high volatile matter non-caking coal (B) as non-caking coal, the blending ratio of high volatile matter non-caking coal (B) should satisfy the following formula (2). Is desirable.
P _B ≦ −1.03 × (VM _H ) +49.53 (2)
here,
P _B : refers to the blending ratio of high volatile content non-coking coal (B) (mass% on dry basis),
(Blend amount of high volatile matter non-coking coal (B), (t) / (total amount of raw coal (t)) × 100
Means what is required by Here, VM _H : The content ratio of the volatile content of the highly volatile non-coking coal (B) is referred to, and the content of volatile content (mass% on a dry base) determined according to JIS M8812.

When the low volatile matter non-caking coal (A) and the high volatile matter non-caking coal (B) are blended together as the non-caking coal, the low volatile matter non-caking coal and the high volatile matter non-caking coal are used. It is desirable to perform the blending ratio of charcoal so that the following formulas (3) and (4) are satisfied.
ΔS = ΔS _A + ΔS _B (3)
S−ΔS ≧ DI ¹⁵⁰ ₁₅ = 84 (4)
Where S: basic strength index of blended coal (DI ¹⁵⁰ ₁₅ )
ΔS _A and ΔS _B : Amount of decrease from the basic strength index S by adding low volatile content non-coking coal (A) or high volatile content non-coking coal (B) (DI ¹⁵⁰ ₁₅ )

The low volatile content non-coking coal (A) and the high volatile content non-coking coal (B) used in each of the inventions have a gieseler fluidity of MF ≦ 1 ddpm.
It is preferable to be.

  Furthermore, in the present invention, it is preferable that the consolidation molding is performed by cold stamping.

According to the present invention, blended coal containing non-coking coal is molded by a compacting method, and the obtained compacted product is charged into a carbonization chamber of a coke oven and dry-distilled to obtain high strength metallurgical coke, for example, coke. It becomes possible to produce metallurgical coke having a strength index DI ¹⁵⁰ ₁₅ value of 84 or more. Further, according to the present invention, it is possible to produce a high strength metallurgical coke by using a compacted molded product molded at room temperature, and it is possible to reduce equipment costs and energy costs.

Mixing ratio (mass ratio in dry base) of low volatile non-caking coal (A) obtained by blending low volatile non-caking coal (A) and dry distillation and strength index DI ^{150 of} metallurgical coke ₁₅ is a graph showing the relationship with. It is the graph which calculated | required the limit with which the coke strength index | exponent 84 is satisfy | filled about the case where a low volatile matter non-coking coal (A) is used. Compounding ratio (mass ratio on dry base) of high volatile content non-coking coal (B) obtained by blending high volatile content non-coking coal (B) and dry distillation and strength index of metallurgical coke DI ¹⁵⁰ ₁₅ is a graph showing the relationship with. It is the graph which calculated | required the limit with which the coke strength index | exponent 84 is satisfy | filled about the case where a high volatile matter non-coking coal (B) is used. It is a graph which shows the relationship between the coal bulk density of the compacting molding in the experiment which obtains coke for metallurgy by dry-distilling the compacting molding obtained from the combination coal containing non-caking coal, and the coke strength index for product metallurgy.

  The present invention is applied to a method for producing metallurgical coke comprising a series of processes in which a coke raw material is molded by a compacting method, and the obtained molded product is charged and carbonized in a carbonization chamber of a coke oven. Here, the compacting method is a method in which blended coal is compacted and the molded product is charged into a carbonization chamber of a chamber furnace coke oven, and includes a so-called stamping method.

  In this method, the entire blended coal is compacted. Therefore, the total amount of blended coal including non-caking coal is a compacted product of a substantially rectangular parallelepiped block having a width smaller than the furnace width of the carbonizing chamber of the coke oven and the other two sides being 0.5 m or more. Note that the length of the compacted product should be 1/3 to 1/2 or more of the coking chamber furnace length of the coke oven, so that the compacted product can be charged efficiently into the carbonization chamber. It is preferable to carry out.

  In this invention, what mixed the non-caking coal which has a fixed property with the coal which has caking property is used as the coal blend which is the said coke raw material. As coal having caking properties, in addition to so-called strong caking coal, weak caking coal, quasi-strong caking coal, and slightly caking coal used for ordinary blended coal are used. As non-caking coal, the coal has a Gieseler maximum fluidity MF specified by JISM8801 of 1 ddpm or less. Specifically, as coal having caking properties, an ordinary blended coal, for example, a coal mainly composed of strongly caking coal and blended with a required weak caking coal, etc., is selected, and has a certain property. Use non-caking coal.

  There are various non-coking coals having such a maximum Gieseller fluidity. In the present invention, low volatile non-coking coals having a dry base volatile content of more than 10% and less than 23% by mass ratio. Only (A) or high volatile content non-coking coal (B) having a dry base volatile content of more than 32% by mass is used. Here, the dry base volatile content is measured by JISM8812.

Here, so-called anthracite having a volatile content of 10% or less is not regarded as low-volatile non-coking coal (A). As will be shown later, in the present invention, when anthracite is blended as non-coking coal (A), the coke strength index DI ¹⁵⁰ ₁₅ decreases greatly, and only a few percent can be blended at most (see FIG. 2). . Further, non-caking coal having a volatile content of 23 to 32% is also referred to as non-caking coal (low volatile non-caking coal (A) or high volatile non-caking coal (B)) blended in the present invention. do not do. Those having a volatile content in this range are not only causative, but also have limited resources, and are not practical from the viewpoint of expanding the use of non-caking coal that is the object of the present invention. It is. In addition, even if the non-caking coal has a volatile content of more than 32%, the one whose value exceeds 50% has a large decrease in the coke strength index DI ¹⁵⁰ ₁₅ due to its blending. It is good not to adopt as non-coking coal (B).

In the present invention, in blending the non-caking coal (low volatile non-caking coal (A) and / or high volatile non-caking coal (B)), first, the blending ratio of non-caking coal The relational expression of the coke strength index DI ¹⁵⁰ ₁₅ is estimated.

FIG. 1 shows the quality of ordinary blended coal in coke properties, with average Ro: 1.00, MF: 200 ddpm, and TI: 30% non-caking coal (hereinafter referred to as “standard blended coal”). On the other hand, low volatile matter non-caking coal (A) having a dry base volatile content of more than 10% and less than 23% shown in Table 1 is added to form a blended coal, and the low volatile matter content obtained when dry distillation is performed under the following conditions: the mixing ratio of caking coal (a) (weight ratio on a dry basis, _{P a)} is a graph showing the relationship between the strength index ^DI _{0.99 15} of metallurgical coke. Here, the blending ratio P _A (% by mass) of the low volatile content non-coking coal (A) is given by the following formula.
P _A = (Blend amount of low volatile content non-coking coal (A) (t)) / (Total amount of blended coal (t)) × 100

Adjustment of blended charcoal: pulverized to a total amount of 3 mm or less.
Consolidation molding: Adjusting coal blend with 8% (constant) coal moisture and adding non-caking coal at a prescribed blending rate, charge 80 kg of dry base into a 500 mm x 600 mm x 400 mm stainless steel dry distillation can Then, the coal is compacted at room temperature by applying a pressure of 10 to 30 MPa from the upper part of the coal bed in the dry distillation can so as to obtain a coal charging density (1.0 to 1.2 t / m ³ ).
Carbonization: A carbonization can is loaded into a carbonization furnace and carbonized according to the following conditions.
Carbonization oven wall temperature: 1000 ° C (constant)
Dry distillation time: 6 hours Cooling method: Measurement of coke strength index DI ¹⁵⁰ ₁₅ with nitrogen stream: Collect 10 kg of coke with a particle size of 25 mm or more according to JISK2151, and collect all the coke after 150 drum rotation. Then, the weight ratio of coke having a particle diameter of 15 mm or more is measured, and the coke strength index DI ¹⁵⁰ ₁₅ is calculated.

FIG. 1 shows that when non-caking coal is blended, the decrease in the coke strength index is smaller as the volatile content of the blended non-caking coal is higher. FIG. 2 is a graph obtained by arranging the above-mentioned FIG. 1 and obtaining the limit at which the coke strength index 84 is satisfied in the case where the low volatile content non-coking coal (A) is used. From Figure 2, the condition for satisfying the coke strength index 84, it can be seen that determined by the non-tacky volatile content of coals and non-tacky coals compounding ratio P _A.

The relationship shown in FIG. 2 can be expressed by equation (1), and metallurgical metal having sufficient strength even if low volatile content non-coking coal (A) is blended under the conditions satisfying this relationship. Coke can be produced.
P _A ≦ 0.47 × (VM _L ) ^1.4 (1)
here,
VM _L : refers to the content ratio of the volatile content of the low volatile matter non-coking coal (A), and refers to the volatile content (mass% on a dry base) determined by JISM8812.

The above relational expression indicates that if the content of the volatile content of the non-caking coal to be blended is high, the blending ratio of more non-caking coal can be increased. However, as described above, when non-coking coal having a volatile content of 23% or more is used, although the coke strength index DI ¹⁵⁰ ₁₅ is high, resource constraints are large and it is not practical. Therefore, the application range of the above formula (1) is limited to the content (VM _L ) of volatile content of the low volatile content non-coking coal (A) being less than 23%.

FIG. 3 shows blending and dry distillation of the high volatile content non-coking coal (B) having a dry base volatile content of 32% or more shown in Table 2 under the same conditions as those for the low volatile content non-coking coal. is a graph showing the compounding ratio of high volatile free caking (B) obtained (weight percent on a dry basis, P _B) the relationship between the strength index DI ^0.99 ₁₅ of metallurgical coke when tested . Here, the blending ratio P _B of the high volatile content non-coking coal (B) is given by the following.
P _B = (Blend amount of high volatile matter non-coking coal (B) (t)) / (total amount of blended coal (t)) × 100

FIG. 3 shows that when the high volatile content non-coking coal (B) is blended, the decrease in the coke strength index increases as the volatile content (VM _H ) of the blended non-coking coal increases. When the results of FIG. 3 are arranged and the limit at which the coke strength index 84 is satisfied is obtained for the case of using the high volatile content non-coking coal (B), the graph of FIG. 4 is obtained. It can be seen that the conditions satisfying the strength index 84 are determined by the volatile content of the non-coking coal and the blending ratio of the non-coking coal.

The relationship shown in FIG. 4 can be expressed by equation (2), and sufficient strength (in this case) even if high volatile content non-coking coal (B) is blended under the conditions satisfying this relationship , A metallurgical coke having a coke strength index of 84) can be produced.
P _B ≦ −1.03 × (VM _H ) +49.53 (2)
Means what is required by
here,
VM _H : Refers to the content ratio of the volatile content of the high volatile content non-coking coal (B), and refers to the dry base volatile content (mass%) determined according to JIS M8812.

The above relational expression shows that the blending ratio of more non-caking coal can be increased if the volatile content of the high-volatile non-caking coal to be blended is low. However, as described above, when non-coking coal having a volatile content of 32% or less is used, although the coke strength index DI ¹⁵⁰ ₁₅ is high, resource constraints are large and it is not practical. Therefore, the range of application of the above formula (1) is limited to a low volatile content non-coking coal (A) having a volatile content (VM _H ) of more than 32%.

As described above, the coke strength index DI ¹⁵⁰ ₁₅ with respect to the blending ratio of the non-caking coal is used regardless of whether the low-volatile matter non-caking coal (A) or the high volatile content non-caking coal (B) is used. Based on the result, the blending ratio of non-coking coal can be determined so that the required coke strength index DI ¹⁵⁰ ₁₅ satisfies a predetermined value.

According to the present invention, the coke raw material is adjusted according to the blending ratio of the non-caking coal determined as described above, and the compacted product obtained by the compacting method is charged into the carbonization chamber of the coke oven and dry-distilled for metallurgy. Characterized by the production of coke, thereby using a blended coal containing non-coking coal to produce a metallurgical coke having a high coke strength index DI ¹⁵⁰ ₁₅ , for example, DI ¹⁵⁰ ₁₅ of 84 or more. It becomes possible. Hereinafter, specific conditions for carrying out the present invention will be described.

In the present invention, it is necessary to compact the raw coal to sufficiently increase the coal bulk density. FIG. 5 shows a low volatile matter non-coking coal (A) with a raw coal symbol 3 shown in Table 1 and a high volatile non-caking coal (B) with a raw coal symbol 13 shown in Table 2 with respect to the standard blended coal described above. ) Are blended so that the blending ratios P _A and P _B are 10% and 5%, respectively, and the compacted products obtained by varying the compaction molding conditions are dry-distilled under the same conditions as above to obtain the metallurgical coke. It is a graph which shows the obtained experimental result. As shown here, in order to achieve the object of the present invention, it is desirable that the compacting is performed on a dry base so that the density of the compacted product satisfies 1.0 to 1.2 t / m ³ .

  The consolidation molding method is not particularly limited as long as it can be molded so that the entire molded product has a uniform density. For example, preheating stamping described in Patent Document 6 can be used, but normal cold stamping is preferable from the viewpoint of energy saving. As the cold stamping method, a known method, for example, a method of tamping coal with a large number of rod-shaped indenters while charging coal into a coal container little by little can be used. Moreover, the shaping | molding method which applies a pressure uniformly with an indenter etc. to the whole coal bed with which the container was charged can also be used widely.

When producing metallurgical coke according to the present invention, from the viewpoint of stability of blast furnace operation, low volatile matter non-coking coal (A) and high volatile matter so that the coke strength index DI ¹⁵⁰ ₁₅ is 84 or more. It is important to determine the blending ratio of non-caking coal (B). Specifically, these compounding ratios are determined as follows.

(1) When blending only low volatile matter non-caking coal (A) When blending a single coal type, the content of the volatile component is constant, The relational expression of the coke strength index DI ¹⁵⁰ ₁₅ with respect to the blending ratio of charcoal is estimated, and the blending ratio may be determined based on the relational expression so that the coke strength index DI ¹⁵⁰ ₁₅ satisfies 84, for example. In the case where a plurality of coal types are mixed and blended, the weighted average value of the content of the volatile component of each blended coal type is taken, and the above-described step may be performed using this.

(2) In the case of blending only the high volatile content non-coking coal (B) The same as the case of blending only the low volatile content non-coking coal (A).

(3) When using low volatile matter non-caking coal (A) and high volatile content non-caking coal (B) In this case, low volatile content non-caking coal (A) and high volatile content non-caking coal In order to show the tendency that the blending amount of the charcoal (B) has different effects on the coke strength index, the blending ratio of the low volatile matter non-caking coal and the high volatile matter non-caking coal is expressed by the following formulas (3) and (4) To do so.
ΔS = ΔS _A + ΔS _B (3)
S−ΔS ≧ DI ¹⁵⁰ ₁₅ = 84 (4)
Where S: basic strength index of blended coal (DI ¹⁵⁰ ₁₅ )
ΔS _A and ΔS _B : Amount of decrease from the basic strength index (DI ¹⁵⁰ ₁₅ ) due to blending of low volatile content non-coking coal (A) or high volatile content non-coking coal (B)

First, the basic strength index S (DI ¹⁵⁰ ₁₅ ) of the blended coal is obtained. The basic strength index S of the blended coal refers to the coke strength index of the metallurgical coke produced by the blended coal serving as a base into which the non-caking coal is blended. This value can be determined by a normal test furnace. In addition, since a coke intensity | strength index falls by mix | blending non-caking coal, this value must be over 84.

Then, the amount of decrease in coke strength index when blended with low-volatile non-coking coal (A) and high volatile free caking (B), obtains the [Delta] S _A and [Delta] S _B, the blending of these total amount Adjustment is made so that the value subtracted from the basic strength index S of charcoal is 84 or more. In other words, the required coke strength index DI can be obtained by subtracting the total amount of strength reduction when non-caking coal is blended with the base coal blend from the coke strength when using the base coal blend. ¹⁵⁰ ₁₅ is adjusted to 84 or more.

  In the present invention, a compacted product obtained by compacting a blended coal blended with non-caking coal is charged into a carbonization chamber of a normal chamber-type coke oven and dry-distilled. The charging / drying process may be the same as in the case of a normal compacting method, for example, a stamping method. In addition, the shape of the compacted product has a width that can be charged into a coking chamber furnace of the coke oven, and has a length that is 1/3 to 1/2 or more of the coking chamber length of the coke oven, It is particularly preferable to use a rectangular parallelepiped block having a height of 1/2 or more of the chamber height, or a rectangular parallelepiped block having a size substantially equal to the size of the carbonization chamber, whereby the compacted product is charged into the carbonization chamber. Can be performed efficiently.

  As described above, according to the present invention, since the blending standard has not been clear so far, it has become possible to produce high-strength metallurgical coke by appropriately using non-caking coal that could not be used sufficiently. . Thereby, while being able to aim at the reduction of the caking coal indispensable for manufacture of the metallurgical coke, the improvement of the operation efficiency of a coke oven can be aimed at.

Claims (8)

Consolidation coal consisting of a plurality of coal types including caking coal and non-caking coal is consolidated into a substantially rectangular parallelepiped whose width is smaller than the furnace width of the coke oven carbonization chamber and the other two sides are 0.5 m or more. In producing metallurgical coke by molding and charging and dry-distilling the resulting compacted molding into the coking oven carbonization chamber,
As the non-caking coal, a low volatile non-caking coal (A) with a dry base volatile content of more than 10% and less than 23% or a high volatile content of a dry base with a volatile content of more than 32%. Selecting non-coking coal (B);
Estimating the relational expression of the coke strength index DI ¹⁵⁰ ₁₅ with respect to the blending ratio of the non-caking coal for each of the low volatile matter non-caking coal (A) and the high volatile content caking coal (B);
The blending ratio of the non-coking coal is determined so that the coke strength index DI ¹⁵⁰ ₁₅ satisfies a predetermined value with respect to the blending amount of the low-volatile non-coking coal (A) and the high volatile non-coking coal (B). Stages,
Adjusting the coke raw material according to the blending ratio of the non-caking coal to obtain a compacted molded product,
A method for producing metallurgical coke, comprising sequentially performing the step of charging the compacted product into a carbonization chamber of a coke oven and dry-drying. 2. The method for producing a metallurgical coke according to claim 1, wherein the density of the compacted product is 1.0 to 1.2 t / m ³ on a dry basis. The method for producing metallurgical coke according to claim 1 or 2, wherein the blending ratio of non-coking coal is determined so that the coke strength index DI ¹⁵⁰ ₁₅ satisfies 84 or more. When blending only low volatile matter non-caking coal (A) as non-caking coal, the blending ratio of the low volatile matter non-caking coal (A) is such that the following formula (1) is satisfied. A method for producing metallurgical coke according to claim 3.
P _A ≦ 0.47 × (VM _L ) ^1.4 (1)
here,
P _A : refers to the blending ratio (mass% on dry base) of low volatile non-coking coal (A),
(Amount of low volatile non-caking coal (A), (t)) / (total amount of coal (t)) × 100
Means what is required by
VM _L : refers to the content ratio of the volatile content of the low volatile matter non-coking coal (A), and refers to the volatile content (mass% on a dry base) determined by JISM8812. When blending only the high volatile matter non-caking coal (B) as the non-caking coal, the blending ratio of the high volatile content non-caking coal (B) satisfies the following formula (2). A method for producing metallurgical coke according to claim 3.
P _B ≦ −1.03 × (VM _H ) +49.53 (2)
here,
P _B : refers to the blending ratio of high volatile content non-coking coal (B) (mass% on dry basis),
(Amount of high volatile content non-coking coal (A), (t)) / (total amount of blended coal (t)) × 100
Means what is required by
VM _H : Refers to the content ratio of the volatile content of the highly volatile non-coking coal (B), and refers to the volatile content (mass% on a dry base) determined according to JIS M8812. In blending together the low volatile matter non-caking coal (A) and the high volatile matter non-caking coal (B) as the non-caking coal, the low volatile matter non-caking coal and the high volatile matter non-caking coal The method for producing metallurgical coke according to claim 3, wherein the blending ratio is set so as to satisfy the following formulas (3) and (4).
ΔS = ΔS _A + ΔS _B (3)
S−ΔS ≧ DI ¹⁵⁰ ₁₅ = 84 (4)
Where S: basic strength index of blended coal (DI ¹⁵⁰ ₁₅ )
ΔS _A and ΔS _B : Amount of decrease from the basic strength index S by adding low volatile content non-coking coal (A) or high volatile content non-coking coal (B) (DI ¹⁵⁰ ₁₅ ) The low volatile matter non-coking coal (A) and the high volatile content non-caking coal (B) have a gieseler fluidity of MF ≦ 1 ddpm.
The method for producing metallurgical coke according to any one of claims 1 to 6.   The method for producing metallurgical coke according to any one of claims 1 to 7, wherein the compacting is performed by cold stamping.

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