JP2006348309A - Process for production of cokes and productive facilities therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process for the production of cokes and productive facilities therefor, which enable the production of the cokes having improved strength through the adjustment of particle size distribution of the coal used as the raw material, while inhibiting lowering in the productivity and increase in the cost. <P>SOLUTION: The process comprises the following steps: a classification step (sieve) 3 for classifying a part of the coal of the coke raw material to the coal with larger diameters and the coal with smaller diameters; a first pulverizing step (the first pulverizer) 4 for pulverizing the coal with the larger diameters; a first compounding step (the first compounding vessel) 5 for compounding the coal treated at the first pulverizing step with the coal with the smaller diameters; a second compounding step (the second compounding vessel) 6, 7 for treating the compounded coal by the second pulverizing step (the second pulverizer) 8 for treating the compounded coal, and compounding the remainder of the coal of the coke raw material with the pulverized product; a third pulverizing step (the third pulverizer) 9, 10 for pulverizing the compounded coal; and a step for charging the resultant product with the coal treated at the second pulverizing step to a coke furnace. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a production method and production equipment for coke used as an iron-making raw material.

  Coke used as a raw material for iron making desirably has a high strength because it deteriorates the air permeability of the blast furnace when pulverized when charged into the blast furnace. In order to produce high-strength coke, the smaller the coal particle size of the coke raw material, the better. On the other hand, the small particle size coal has problems such as difficulty in handling when charged in the coke oven, Since productivity does not improve, it is considered preferable to use coal having a particle size in the range of, for example, about 0.5 mm to 6 mm. In order to obtain such a particle size range, the pulverized coal can be made into a coal having a particle size of only 0.5 mm to 6 mm by sieving, except for those less than 0.5 mm and exceeding 6 mm. However, even if it exceeds 6 mm, it is pulverized again and used as a raw material for coke, but if it is less than 0.5 mm, it will be disposed of without a preferred use, resulting in processing costs and undesirable yield improvement. Since the filling rate of coal in the coke oven also decreases, this is not a realistic method.

  As a method of adjusting the particle size by specifying only the upper limit of the particle size of coal for charging coke ovens, the coal is classified with a sieve having a sieve that can obtain a predetermined particle size, and the under-sieved portion is used as a raw material for coke. In addition, a method of repeating pulverization and classification until the coarse particle portion on the sieve passes through the sieve is known (for example, see Patent Document 1). In the method described in Patent Document 1, the sieve grain is changed between coal rich in active ingredients (soft coal) and coal rich in active ingredients (hard coal), and coal particles not rich in active ingredients. The diameter is made smaller and used as a raw material. Coal whose particle size is adjusted to each is appropriately mixed and charged into a coke oven, and coke having a higher strength than conventional ones is produced.

In addition, by increasing the packing density of coal in the coke oven, it is possible to improve productivity and to produce high-strength coke. Of the coal for charging a coke oven, which is classified and pulverized with a crusher with the classified large particle size and small particle size or less and charged into the coke oven together with the previously classified medium particle size coal. A particle size adjustment method is also known (see, for example, Patent Document 2).
JP 56-32587 A Japanese Patent Laid-Open No. 11-302662

  However, in the method described in Patent Document 1, it is necessary to repeatedly crush coal having a predetermined particle size or more until it becomes smaller than the predetermined particle size, and the same coal is sieved and pulverized many times. Productivity decreases.

  Moreover, although the method of patent document 2 is the maximum number of times of crushing about the same coal, since the coal below the small particle diameter obtained by crushing is again crushed with a crusher, a fine particle increases. Thus, even if a distribution close to the ideal coal particle size distribution state in which the coke oven is in a close-packed state is obtained, it is not desirable in actual operation. Moreover, since the crushed coal is classified into three stages of large particle size, medium particle size, and small particle size, the equipment cost for sieving increases.

  Therefore, the object of the present invention is to solve such problems of the prior art, and to suppress the decrease in productivity and the increase in cost, while keeping the particle size distribution of the coke raw material coal within an appropriate range, thereby improving the coke strength. The object is to provide a method and equipment for producing coke, which is possible.

The features of the present invention for solving such problems are as follows.
(1) A classification step of classifying at least a part of coal as a coke raw material into coal having a large particle size and coal having a smaller particle size than the coal, and first pulverization for pulverizing the coal having a large particle size After processing by a step, a first blending step of blending the coal pulverized in the first pulverization step and the coal having a small particle size, and a second pulverization step of pulverizing the blended coal, A coke production method comprising charging a coke oven together with the remainder of the coal as the coke raw material.
(2) a classifying step of classifying a part of coal as a coke raw material into coal having a large particle size and coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, Coke after having been treated by a blending step of blending the coal treated in one grinding step, the coal having a small particle diameter and the remainder of the coal as the coke raw material, and a second grinding step of grinding the blended coal A method for producing coke, which is charged in a furnace.
(3) A classification step of classifying a part of coal as a coke raw material into coal having a large particle size and coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, Coal which is treated by a first blending step of blending the coal treated in one grinding step with the coal having a small particle diameter and a second grinding step of grinding the blended coal to become the coke raw material After being treated by the second blending step for blending the remainder of the mixture and the third grinding step for grinding the blended coal, the coal treated in the second grinding step is charged into a coke oven. Coke production method.
(4) A method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a particle size. A classification step of classifying the large coal and a coal having a particle size smaller than the coal, a first pulverization step of pulverizing the coal having a large particle size, the coal treated in the first pulverization step, and the After processing by a first blending step of blending a small particle size coal and / or the remainder of the coal (X) and a second grinding step of grinding the blended coal, the coal (X) and A method for producing coke, wherein the coal (Y) is charged into a coke oven.
(5) A method of producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X),
A classification step of classifying at least a part of the coal (X) into a coal having a large particle size and a coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, and the first pulverization After processing by the compounding process which mix | blends the coal processed by the process, the said small particle size coal, the remainder of coal (X), and the said coal (Y), and the 2nd grinding | pulverization process which grind | pulverizes this compounded coal A method for producing coke, which is charged in a coke oven.
(6) A method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a particle size. A classification process for classifying the large coal and a small particle diameter coal, a first pulverization process for pulverizing the large particle coal, the coal treated in the first pulverization process and the small particle diameter The first blending step of blending coal and / or the remainder of the coal (X) and the second milling step of pulverizing the blended coal, and the second blending the coal (Y) A method for producing coke, characterized by charging the coal (X) and the coal (Y) into a coke oven after the blending step and the third pulverization step of pulverizing the blended coal.
(7) A method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a particle size. A classification process for classifying the large coal and a small particle diameter coal, a first pulverization process for pulverizing the large particle coal, the coal treated in the first pulverization process and the small particle diameter The first blending step of blending coal and the second milling step of grinding the blended coal, and the second of blending the remainder of the coal (X) and the coal (Y) separately. Coke production characterized by charging the coal (X) and the coal (Y) into a coke oven after treating in a blending step and a third grinding step of separately grinding the blended coal. Method.
(8) A method for producing coke using coal (X ′) having a large amount of inert and coal (Y ′) having a smaller amount of inert than the coal (X ′), wherein the coal (X ′) A classification step of classifying at least a part of the coal into a coal with a large particle size and a coal with a particle size smaller than the coal, a first pulverization step of pulverizing the coal with a large particle size, and the first pulverization step. After processing by the first blending step of blending the treated coal and the small particle size coal and / or the remainder of the coal (X ′) and the second grinding step of grinding the blended coal The method for producing coke, wherein the coal (X ′), the coal (Y ′) and the coke oven are charged.
(9) A method for producing coke using coal (X ′) having a large amount of inert and coal (Y ′) having a smaller amount of inert than the coal (X ′),
A classification step of classifying at least a part of the coal (X ′) into a coal having a large particle size and a coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, By the blending step of blending the coal treated in the grinding step, the small particle size coal, the remainder of the coal (X ′) and the coal (Y ′), and the second grinding step of grinding the blended coal A method for producing coke, wherein the coke oven is charged after the treatment.
(10) A method for producing coke using coal (X ′) having a large amount of inert and coal (Y ′) having a smaller amount of inert than the coal (X ′), wherein the coal (X ′) A classification step of classifying at least a part of the coal into a coal with a large particle size and a coal with a particle size smaller than the coal, a first pulverization step of pulverizing the coal with a large particle size, and the first pulverization step. Processing by a first blending step of blending the treated coal with the small particle size coal and / or the remainder of the coal (X ′), and a second grinding step of grinding the blended coal; The coal (X ′) and the coal (Y ′) are treated by a second blending step for blending the coal (Y ′) and a third grinding step for pulverizing the blended coal. A method for producing coke, characterized in that it is charged into a coke.
(11) A method for producing coke using coal (X ′) having a large amount of inert gas and coal (Y ′) having a smaller amount of inert than the coal (X ′), wherein the coal (X ′) A classification step of classifying at least a part of coal into a coal with a large particle size and a coal with a small particle size, a first pulverization step of pulverizing the coal with a large particle size, and the coal treated in the first pulverization step And the second blending step of grinding the blended coal, and the remainder of the coal (X ′) and the coal (Y ′). Are processed in a second blending step in which the coal is separately blended and a third grinding step in which the blended coal is ground separately, and then the coal (X ′) and the coal (Y ′) are loaded in a coke oven. A method for producing coke, comprising:
(12) The coke according to any one of (1) to (11), wherein the coal is classified into a coal having a particle size set within a range of 1 to 20 mm and a coal having a large particle size and a coal having a small particle size. Production method.
(13) A classifier that classifies a part of coal as a coke raw material into coal having a large particle diameter and coal having a small particle diameter, a first pulverizer that pulverizes the coal having a large particle diameter, A blending tank for blending the coal treated in one grinding machine, the coal having a small particle diameter and the remainder of the coal as the coke raw material, a grinding machine for grinding the coal blended in the blending tank, and the grinding machine A coke production facility comprising a transporter for transporting coal treated in step 1 to a coke oven.
(14) A classifier that classifies a part of coal as a coke raw material into coal having a large particle diameter and coal having a small particle diameter, a first pulverizer that pulverizes the coal having a large particle diameter, A first blending tank for blending the coal treated with one grinding machine and the coal having a small particle diameter, a second grinding machine for grinding the coal blended in the first blending tank, and the coke raw material A second compounding tank for compounding the remainder of the coal, a third pulverizer for pulverizing the coal compounded in the second compounding tank, the coal treated in the second pulverizer and the third A coke production facility, comprising: a transporter for transporting the coal treated by the pulverizer to a coke oven.
(15) The coke production facility according to (13) or (14), wherein the pulverization capacity of the first pulverizer is larger than that of the second pulverizer.

  In the present invention, at least a part of coal as a raw material for coke is divided into coal having a large particle size and coal having a small particle size, and after pulverizing the coal having a large particle size, Is mixed again and pulverized again, and charged in a coke oven to produce coke. That is, a classification step of classifying at least a part of coal as a coke raw material into coal having a large particle size and coal having a smaller particle size than the coal, and a first pulverizing step of pulverizing the coal having a large particle size And after the first pulverizing step of blending the coal pulverized in the first pulverizing step and the coal having a small particle size, and the second pulverizing step of pulverizing the blended coal, A method for producing coke, comprising charging a coke oven together with the remainder of coal as a coke raw material. For the classification of coal having a large particle size and coal having a small particle size, it is sufficient to perform sieving using a sieve. Therefore, as a classification process, for example, a sieve is used to place coal on and below the sieve. Classify. In the first pulverization step, pulverization is performed on the sieve having a particle size larger than the sieve mesh to reduce the particle size. For sieving that has a particle size equal to or smaller than the sieve mesh, the second pulverization step is performed after the first pulverization step is blended with the first pulverization step (first blending step) without performing the first pulverization step. The pulverization process is performed. In the first blending step, it is sufficient to put coal with a large particle size and coal with a small particle size into a blending tank or the like to make a mixed state, and it is necessary to provide a special mixing means in the following blending step. There is no. By pulverizing only the coal having a large particle size in advance (first pulverization step), the proportion of coal having a large particle size is reduced. As a result, the ratio of coarse particles is reduced, so that it is possible to reduce the pulverization ability in the second pulverization step and pulverize. Is suppressed, and the particle size distribution of coal is improved as a whole. After pulverizing coal on a sieve with a large particle size in the first pulverization step, the same coal is repeatedly pulverized by pulverizing in the second pulverization step together with sieving without repeating classification by sieving again. This is advantageous in terms of productivity. Further, although coal having a large particle size is present after the first pulverization step, it is appropriately pulverized and refined in the second pulverization step. Therefore, even after the pulverization process in the first pulverization process and the second pulverization process, there is a certain proportion of coal with a large particle size that is classified on the sieve in the classification process. Compared to the case where it is not performed, the ratio is sufficiently reduced.

  Therefore, it is desirable to make the pulverization capacity smaller in the “second pulverization process” than in the “first pulverization process”. For example, the “first pulverization process” is different from the “second pulverization process”. This can be dealt with by using a pulverizer, or by reducing the number of revolutions of the crushing blade of the pulverizer so that the pulverization capability is lower in the “second pulverization step” than in the “first pulverization step”.

  When all the coal as the coke raw material is processed in the classification step and the first pulverization step, the remaining coal as the coke raw material naturally does not exist. On the other hand, when only a part of the coal as the coke raw material is processed in the classification step and the first pulverization step, the remainder of the coal as the coke raw material is coke together with the coal processed in the classification step and the first pulverization step. Charge into the furnace. That is, a classifying step of classifying a part of coal as a coke raw material into coal having a large particle size and coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, and the first A coke oven after being treated by a blending step of blending the coal treated in the pulverization step, the coal having a small particle diameter and the remainder of the coal as the coke raw material, and a second pulverization step of pulverizing the blended coal It is desirable to insert in

  When only a part of the coal that is the raw material for coke is processed in the above classification process and the first crushing process, the quality of the coal, such as the hardness and the amount of inert, varies depending on the brand, and the crushing conditions must be adjusted for each brand. Is desirable. Accordingly, a plurality of blending tanks are preferably arranged for each coal quality or brand, and a plurality of crushers are also arranged correspondingly, and the remainder of the coal is desirably separately pulverized. That is, a classifying step of classifying a part of coal as a coke raw material into coal having a large particle size and coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, Of the coal to be used as the coke raw material is processed by the first blending step of blending the coal pulverized in the pulverization step and the coal having the small particle diameter and the second pulverization step of pulverizing the blended coal. The remainder is crushed by the second blending step of blending the remainder of the coal as the coke raw material and the third pulverization step of pulverizing the blended coal, and coke together with the coal pulverized in the second pulverization step. It is desirable to charge the furnace. For the remainder of the coal that will be the coke raw material that is not treated in the classification step, the third pulverization step should be omitted if it is fine-grained or has a suitable particle size distribution for charging into the coke oven. Is also possible.

  Moreover, when processing only a part of coal used as a coke raw material by said classification process and a 1st grinding | pulverization process, it is desirable to process hard coal preferentially. That is, when producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), at least a part of the coal (X) having a high hardness has a large particle size. A classification step of classifying coal and coal having a particle size smaller than that of the coal, a first pulverization step of pulverizing the coal having a large particle size, the coal treated in the first pulverization step, and the particle size Of the coal (X) and the coal after being treated by a first blending step of blending a small amount of coal and / or the remainder of the coal (X) and a second grinding step of pulverizing the blended coal. It is preferable to charge (Y) into a coke oven.

  Further, coal (Y) can also be blended in the first blending step and pulverized in the second pulverization step. That is, a method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a particle size. Classification process for classifying into large coal and coal with small particle diameter, first pulverization process for pulverizing coal with large particle diameter, coal treated in the first pulverization process, and coal with small particle diameter It is desirable that the coke oven is charged after the blending step of blending the remainder of the coal (X) and the coal (Y) and the second pulverization step of pulverizing the blended coal.

  Also, the quality of coal, such as hardness and inert amount, varies depending on the brand, and it is desirable to pulverize by adjusting the grinding conditions for each brand. Therefore, it is preferable that a plurality of blending tanks are arranged according to quality or brand of coal, and a plurality of crushers are also arranged correspondingly. Coal (X) having a higher hardness and coal having a hardness lower than that of the coal (X) ( Y) and a method of producing coke using a classification step of classifying at least a part of the coal (X) into coal having a large particle size and coal having a small particle size, and the coal having a large particle size. A first pulverization step of pulverizing the coal, a first blending step of blending the coal treated in the first pulverization step with the small particle size coal and / or the remainder of the coal (X), The coal is treated by a second pulverizing step for pulverizing the blended coal, and then treated by a second blending step for blending the coal (Y) and a third pulverizing step for pulverizing the blended coal. (X) and the coal (Y) into a coke oven It is desirable to enter.

  Furthermore, in the above, it is also possible to mix | blend the remainder of coal (X) and coal (Y) using a separate mixing tank, respectively, and to grind | pulverize for each mixing tank. That is, a method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a particle size. Classification process for classifying into large coal and coal with small particle diameter, first pulverization process for pulverizing coal with large particle diameter, coal treated in the first pulverization process, and coal with small particle diameter And a second blending step of blending the remainder of the coal (X) and the coal (Y) separately, and a second blending step of grinding the blended coal. It is desirable to charge the coal (X) and the coal (Y) into a coke oven after the process and the third pulverization step of separately pulverizing the blended coal.

  Moreover, it is a method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a particle size. Classification process for classifying into large coal and coal with small particle diameter, first pulverization process for pulverizing coal with large particle diameter, coal treated in the first pulverization process, and coal with small particle diameter And / or a first blending step of blending at least a part of the remainder of the coal (X) and / or at least a portion of the coal (Y), and a second grinding step of grinding the blended coal And after the second blending step of blending the remaining coal not treated in the second grinding step and the third grinding step of grinding the blended coal, the coal (X) and Charge the coal (Y) into a coke oven. And it is possible to select as the preferred method also.

  In order to group coal, which is usually a coke raw material composed of multiple brands, into high-hardness coal (X) and low-hardness coal (Y), use predetermined criteria that are set appropriately. Thus, it may be classified into coal (X) whose hardness is higher than a predetermined standard and coal (Y) whose hardness is lower than a predetermined standard. For example, when coke is produced using coal brands A, B, and C, coal brand A having the highest average hardness is classified as coal (X) having high hardness, and coal brands B and C are classified into coal having low hardness ( Y). In addition, when using the coal brands D, E, and F, which have lower hardness than the coal brands A, B, and C, the predetermined standard is set low and the coal brands D, E, and F are relatively hard. Can be classified into coal (X) having high hardness. It is desirable to set the predetermined standard so that the cost and production efficiency of coke production are optimized in consideration of the brand of raw material coal used, the production capacity of coke, and the like. Further, as is clear from the above example, the high hardness coal (X) and the low hardness coal (Y) are not limited to a single brand, but are composed of a plurality of brands of coal. It is what you have.

  The reason why hard coal is preferentially treated in the first crushing process is that coal with a large particle size is mainly high-hardness coal, and the number of times of crushing hard coal that is difficult to grind is selected. This is because productivity can be improved by increasing the priority. That is, in the case where the processing in the classification step and the first pulverization step is not performed for all raw material coals, it is preferable to prioritize the coal (X) having high hardness to perform the classification and pulverization treatment. If only a part of the coal (X) is processed in the classification step and the first pulverization step, it is effective. For example, the coal is classified into coal having a large particle size and coal having a small particle size, and the particle size is large. Even if the amount of coal that is pulverized into coal is about 10% of the total amount of coal, the particle size distribution is improved significantly by preferentially classifying and pulverizing coal (X) in the entire raw material. can do. The classification of coal (X) and other coals is not strict, and the average hardness is defined for each brand of coal, and if the average hardness exceeds a predetermined standard, it will be classified as coal (X). What is necessary is just to classify | categorize and it does not interfere even if coal (X) contains the coal of the hardness below a predetermined standard partially. The particle size distribution is improved as the proportion of the coal (X) in the classification step and the first pulverization step is increased, but the processing cost is also increased.

  It is known that the hardness of coal varies depending on the production area. It is desirable to use HGI as a predetermined standard when classifying coal (X) when preferentially treating high-hardness materials in the classification process / first crushing process. It is preferable that a certain HGI (hard glove index: according to JIS-M-8801) is 80 or less as coal (X). As the coal having an HGI of 80 or less, it is preferable to use non-thin coal. Many non-thin coals have high hardness of HGI 80 or less and are inexpensive coals. Judgment of the hardness of coal with respect to a predetermined standard can be performed, for example, by measuring an average HGI for each brand of coal and comparing these average values with a predetermined standard.

  Moreover, when processing only a part of coal used as a coke raw material by said classification | category process and a 1st grinding | pulverization process, it is desirable to process coal with much inert amount preferentially. That is, a method for producing coke using coal (X ′) having a large amount of inert gas and coal (Y ′) having a smaller amount of inert than the coal (X ′), and comprising at least the coal (X ′). A classifying step for classifying a part of the coal into a coal having a large particle size and a coal having a smaller particle size than the coal, a first pulverizing step for pulverizing the coal having a large particle size, and the first pulverizing step. After being treated by a first blending step of blending the prepared coal with the small particle size coal and / or the remainder of the coal (X ′) and a second grinding step of grinding the blended coal, The coal (X ′), the coal (Y ′), and a coke oven are preferably charged.

  On the other hand, coal (Y ′) with a small amount of inert can be blended with coal (X ′) with a large amount of inert and pulverized. A method for producing coke using coal (Y ′) having a smaller amount of inert than coal (X ′), wherein at least a part of the coal (X ′) is composed of coal having a large particle size and small particle size. A classification step of classifying into coal, a first pulverization step of pulverizing the coal having a large particle size, coal treated in the first pulverization step, coal having a small particle size, and coal (X ′) It is desirable to charge the coke oven after processing by the blending step of blending the remainder and the coal (Y ′) and the second grinding step of grinding the blended coal.

  Also, the quality of coal, such as hardness and inert amount, varies depending on the brand, and it is desirable to pulverize by adjusting the grinding conditions for each brand. Therefore, it is preferable that a plurality of blending tanks are arranged according to quality or brand of coal, and a plurality of crushers are also arranged correspondingly. Coal (X ′) with a larger amount of inert and the amount of inert than the coal (X ′) Is a method for producing coke using a small amount of coal (Y ′), wherein at least a part of the coal (X ′) is classified into coal having a larger particle size and coal having a smaller particle size than the coal. A classification step, a first pulverization step of pulverizing the coal having a large particle size, coal treated in the first pulverization step, the small particle size coal and / or the remainder of the coal (X ′) The first blending step for blending and the second milling step for milling the blended coal, the second blending step for blending the coal (Y ′), and the blended coal is ground. The coal (X ) And it is preferable that the the coal (Y ') charged into the coke oven.

  Furthermore, in the above, it is preferable that the remainder of coal (X ′) and coal (Y ′) are blended using separate blending tanks and pulverized for each blending tank. That is, a method for producing coke using coal (X ′) having a large amount of inert gas and coal (Y ′) having a smaller amount of inert than the coal (X ′), and comprising at least the coal (X ′). A classification step of classifying a part of the coal into a coal with a large particle size and a coal with a small particle size, a first pulverization step of pulverizing the coal with a large particle size, and the coal treated in the first pulverization step; A first blending step of blending the coal having a small particle diameter and a second grinding step of pulverizing the blended coal, and the remainder of the coal (X ′) and the coal (Y ′) are treated. The coke oven is charged with the coal (X ′) and the coal (Y ′) after being treated by the second blending step of blending separately and the third grinding step of separately grinding the blended coal. It is desirable to do.

  Furthermore, it is a method for producing coke using coal (X ′) having a large amount of inert and coal (Y ′) having a smaller amount of inert than the coal (X ′), wherein at least of the coal (X ′). A classifying step for classifying a part of the coal into a coal having a large particle size and a coal having a smaller particle size than the coal, a first pulverizing step for pulverizing the coal having a large particle size, and the first pulverizing step. A first blending step of blending the formed coal with at least a portion of the coal having the small particle size and / or the remainder of the coal (X ′) and / or at least a portion of the coal (Y ′); The second pulverization step of pulverizing the blended coal, the second pulverization step of pulverizing the blended coal, and the second pulverization step of blending the remaining coal not processed by the second pulverization step. Processed by the process, with the coal (X ′) A serial coal (Y ') which can be selected as the method it is also desirable to charged into the coke oven.

  When coal having a large amount of inert coal is used as the coke raw material, cracks are likely to occur during the coke production process, and the strength of the coke produced tends to be reduced. Therefore, it is preferable to disperse as much as possible when charging into the coke oven, and for this purpose, it is desirable to pulverize into fine particles. Therefore, the coke strength can be improved by preferentially increasing the number of times of pulverizing coal with a large amount of inert. Therefore, in the case where the processing in the classification step and the first pulverization step is not performed for all raw material coals, it is preferable to prioritize the coal (X ′) having a large amount of inerting to perform the classification and pulverization treatment. If only a part of the coal (X ′) is processed in the classification step and the first pulverization step, it is effective. For example, the coal is separated into coal having a large particle size and coal having a small particle size. Even if the amount of coal that is pulverized into large coal is about 10% of the total amount of coal, preferential classification and pulverization of coal (X ') out of the entire raw material will result in significant particle size distribution as a whole. Can be improved. The classification of coal (X ') and other coals is not strict, and the average amount of inert for each brand of coal is specified, and if the average value exceeds a predetermined standard, coal (X The coal (X ′) may partially contain coal having a hardness below a predetermined standard. Increasing the proportion of coal (X ′) to be processed in the classification step and the first pulverization step increases the coke strength, but also increases the processing cost.

  Coal is known to have different amounts of inert (non-molten component) depending on the production area. When processing a large amount of inerts preferentially in the classification process / first crushing process, the criteria for classifying coal (X ′) with a large amount of inerts are the brands of the raw coal used and the coke It is desirable to set as appropriate so that the cost and production efficiency of coke production are optimized in consideration of production facility capacity, etc., but coal with an inert amount of 35% or more is regarded as coal with a large amount of inert (X ′). It is particularly preferable to do this. As coal having an inert amount of 35% or more, it is preferable to use non-thin coal. Many non-thin coals have a high inert amount and are inexpensive. The determination of the amount of inert coal can be performed, for example, by measuring the average amount of inert for each brand of coal and comparing these average values with a predetermined standard (for example, 35% of the amount of inert).

  Therefore, when only a part of the coal used as a coke raw material is processed in the classification step and the first pulverization step, the coal is classified using both the hardness and the inert amount criteria, and the high hardness and inert amount are classified. It is desirable to preferentially treat a large amount of material in the classification step / first grinding step. Particularly preferably, the coal having an HGI of 80 or less and an inert amount of 35% or more is preferentially treated in the classification step / first pulverization step. Non-thin cohesive coal is very suitable because it has many varieties having an HGI of 80 or less and an inert amount of 35% or more and is inexpensive.

  In the classification process, when classifying coal into coal having a large particle size and coal having a small particle size, the coal is classified into a coal having a particle size set within a range of 1 to 20 mm and a coal having a large particle size and a coal having a small particle size. It is preferable to classify. If the classified particle size (the particle size at the time of classification, for example, corresponding to the mesh size at the time of classification using a sieve) exceeds 20 mm, the proportion of coarse particles increases and the coke strength decreases. On the other hand, if the classified particle size is less than 1 mm, the proportion of fine particles increases, and the proportion of coal exceeding the classified particle size after separation into coal exceeding the classified particle size and coal smaller than the classified particle size increases. And since the processing amount in a 1st grinding | pulverization process increases, productivity also falls. FIG. 3 is a graph for explaining the production cost of coke when the classified particle diameter in the classification step is changed. The coke strength increases as the classified particle size decreases, and the higher the coke strength, the lower the reflectivity (Ro) of the coal used (mixed coal). The smaller the classified particle size, the lower the cost of blended coal per unit production of coke, and the greater the merit in terms of cost (A in FIG. 3). On the other hand, the charging amount per kiln of the coke oven increases as the classified particle size increases, and the amount of coke increases as the charging amount per kiln increases. The coke production cost decreases and the merit in terms of cost increases (B in FIG. 3). Therefore, the total cost (C in FIG. 3), which is the cost of coke production per unit production of coke as a whole, decreases when the classified particle size is about 20 mm or less, and the classified particle size is about 3 to 10 mm. Sometimes it tends to be particularly low. Therefore, it is desirable in terms of cost to have a classified particle size of 1 to 20 mm, particularly desirably about 3 to 10 mm. The coke strength was evaluated by the coke drum strength (DI30 / 15). The charging amount per kiln was evaluated by a kiln charging index indicating the filling rate of coal into the coke oven. If the particle size distribution of the raw coal is in a certain range, it is preferable that the proportion on the small particle side is large, and therefore a more desirable classified particle size is 3 to 6 mm. The classified particle size can be easily adjusted, for example, by changing the mesh of the sieve when classifying coal.

  Next, the coke production facility of the present invention will be described.

  In order to carry out the above-mentioned method for producing coke, a classifier for classifying a part of coal as a coke raw material into coal having a large particle size and coal having a small particle size, and pulverizing the coal having a large particle size A first pulverizer, a blending tank for blending the coal treated by the first pulverizer, the coal having a small particle diameter and the remainder of the coal as the coke raw material, and a coal blended in the blending tank. It is preferable to use a coke production facility characterized by comprising a pulverizer for pulverization and a conveyor for conveying coal treated by the pulverizer to a coke oven.

  Also, the quality of coal, such as hardness and inert amount, varies depending on the brand, and it is desirable to pulverize by adjusting the grinding conditions for each brand. Therefore, it is preferable to arrange a plurality of blending tanks according to quality or brand of coal, and a plurality of crushers to correspond to the blending tanks. Using the second blending tank and the third crusher, A classifier that classifies a part into coal having a large particle size and coal having a small particle size, a first pulverizer that pulverizes the coal having a large particle size, and coal that has been processed by the first pulverizer And a first compounding tank for compounding the coal having a small particle diameter, a second pulverizer for pulverizing the coal compounded in the first compounding tank, and a second compounding unit for the remainder of the coal as the coke raw material. Two blending tanks, a third pulverizer for pulverizing coal blended in the second blending tank, coal treated with the second pulverizer, and coal treated with the third pulverizer Of coke, characterized in that it comprises a transporter for transporting to a coke oven It is preferable to use an elephant facilities.

  In the blending tank, in addition to storing the coal, there is an effect of homogenizing the properties of the coal when charging into the coke oven by sequentially charging a plurality of brands of coal and cutting out after storage in the blending tank. Only a single brand of coal may be stored in the same blending tank, but if it is mixed with other brands of coal on the conveyor after crushing, the brand of coal charged into the coke oven will be Partial bias is prevented.

  Further, a sieve for classifying a part of the coal carried out from the coal yard, a first pulverizer for pulverizing the coal on the sieve classified by the sieve, and pulverized by at least the first pulverizer A first blending tank for mixing and storing coal and the unsieved coal classified by the sieve, a second pulverizer for pulverizing the coal cut out from the first blending tank, and the coal yard Crushed by the second pulverizer, the second pulverizer for storing the remaining coal transported from the above, the third pulverizer for pulverizing the coal cut out from the second compounder It is preferable to use a coke production facility characterized by comprising a transporter for transporting coal and coal pulverized by the third pulverizer to a coke oven. Coal other than the coal classified by the sieve can be stored in the first blending tank. In this case, the mixing ratio of different brands of coal increases, and the quality of the product coke becomes more uniform.

  Furthermore, it is desirable that the pulverization capacity of the first pulverizer is larger than that of the second pulverizer. As explained above, since only the coal with a large particle size is pulverized in advance by the first pulverizer, the “second pulverizer” has a smaller pulverization capacity than the “first pulverizer”. It is desirable to use it.

  FIG. 1 is a schematic view showing an embodiment of a coke production facility of the present invention.

  Of the coal yards 1 and 2, a part of the coal in the coal yard 1 is unloaded and sieved by the sieve 3, and the sieve a having a particle size exceeding a predetermined particle size is pulverized by the first pulverizer 4. Charge into one blending tank 5. The sieve b is put into the first blending tank 5 as it is. The remainder of the coal in the coal yard 1 is appropriately transported to the first blending tank 5 and the second blending tanks 6 and 7 as they are. The coal in the coal yard 2 is also appropriately transported to the first blending tank 5 and the second blending tanks 6 and 7. The coal in the first mixing tank 5 is appropriately pulverized by the second pulverizer 8. The coal in the second compounding tank 6 is appropriately pulverized by the third pulverizer 9 and the coal in the second compounding tank 7 is appropriately pulverized by the third pulverizer 10, and the coal pulverized by each pulverizer is mixed by a conveyor or the like. By being conveyed, it is homogenized to some extent and charged into the coke oven.

  In FIG. 1, the second blending tanks 6 and 7 are each installed in three tanks, the coal in the second blending tank 6 is crushed by the third crusher 9, and the coal in the second blending tank 7 is the third By crushing with the pulverizer 10, crushing by brand can be performed.

  When using non-slightly cohesive coal and strongly caking coal as raw material coal, it is desirable that coal yard 1 be non-slightly caking coal and coal yard 2 be strongly caking coal.

  Coke was manufactured using the coke manufacturing equipment shown in FIG. As raw material coal, 80% non-fine coking coal and 20% strong caking coal (HGI: about 85, inert amount about 30%) are used. Sieve the viscous coal (HGI: about 75, inert amount: about 36%) (classification process), and crush it over the 6 mm sieve with a hammerhead type first crusher at 680 rpm (the first Pulverizing step), and all the pulverized material is put into the first blending tank together with 6mm or less coal under sieve, and then pulverized at 570 rpm (second pulverizing step) with a hammerhead type second pulverizer. It was. The remaining non-microcoking coal and strong coking coal were separately pulverized at 600 rpm with a plurality of hammerhead type third pulverizers (third pulverization step), and sieved and pulverized. It mixed with the cohesive coal on the conveyor, and it charged in the coke oven, and manufactured coke (example of this invention). As a comparative example, a conventional manufacturing method in which non-microcoking coal and strong caking coal are separately pulverized (equivalent to only the third pulverizing step), mixed on a conveyor, and charged into a coke oven. Coke was also produced.

  In FIG. 2, the particle size distribution of the coal powder (mixed coal) before charging into the coke oven manufactured using the method of the present invention is shown. The particle size distribution of the blended coal in the conventional case not using the classification step and the first pulverization step, which is a comparative example, is also shown. It can be seen that when the method of the present invention is used, the particle size distribution becomes narrower and the number of coal particles having a preferable particle size in the range of 0.5 to 6 mm increases.

  The drum strength (DI) of the produced coke was measured. The drum strength (DI30 / 15) of the coke produced by the method of the present invention is 94.2, which is 0 in comparison with the drum strength (DI30 / 15) of the conventional coke as a comparative example being 94.0. Improved by 2%. DI30 / 15 is the drum strength measured under the condition of 30 revolutions and 15 minutes by the rotational strength test method of JIS K2151.

  It was found that if coke having the same strength as the conventional one is produced, the proportion of non-microcoking coal can be increased to about 85%, and the cost of coke can be reduced.

  As in Example 1, coke was produced using the coke production facility shown in FIG. As raw material coal, 80% non-fine coking coal and 20% strong caking coal (HGI: about 85, amount of inert about 30%) are used. Sieve the viscous coal (HGI: about 75, inert amount: about 36%) (classification process), and crush it over the 6 mm sieve with a hammerhead type first crusher at 680 rpm (the first Pulverizing step), and all the pulverized material is put into the first blending tank together with 6mm or less coal under sieve, and then pulverized at 570 rpm (second pulverizing step) with a hammerhead type second pulverizer. It was. The remaining non-microcoking coal and strong coking coal were separately pulverized at 600 rpm with a plurality of hammerhead type third pulverizers (third pulverization step), and sieved and pulverized. It mixed with the cohesive coal on the conveyor, and it charged in the coke oven, and manufactured coke (example of this invention). As a comparative example, a conventional manufacturing method in which non-microcoking coal and strong caking coal are separately pulverized (equivalent to only the third pulverizing step), mixed on a conveyor, and charged into a coke oven. Coke was also produced.

  The drum strength (DI) of the produced coke was measured. The drum strength (DI30 / 15) of the coke produced by the method of the present invention is 94.3, which is 0 compared to the drum strength (DI30 / 15) of the conventional coke as a comparative example, which was 94.0. Improved by 3%.

  It was found that if coke having the same strength as the conventional one is produced, the proportion of non-microcoking coal can be increased to about 87%, and the cost of coke can be reduced.

  As in Example 1, coke was produced using the coke production facility shown in FIG. As raw material coal, 80% non-fine coking coal and 20% strong caking coal (HGI: about 85, amount of inert about 30%) are used. Sieve the viscous coal (HGI: approx. 75, inert amount: approx. 22%) (classification process) and crush it at 680 rpm with the first hammerhead type crusher (the first crusher) Pulverizing step), and all the pulverized material is put into the first blending tank together with 6mm or less coal under sieve, and then pulverized at 570 rpm (second pulverizing step) with a hammerhead type second pulverizer. It was. The remaining non-microcoking coal and strong coking coal were separately pulverized at 600 rpm with a plurality of hammerhead type third pulverizers (third pulverization step), and sieved and pulverized. It mixed with the cohesive coal on the conveyor, and it charged in the coke oven, and manufactured coke (example of this invention). As a comparative example, a conventional manufacturing method in which non-microcoking coal and strong caking coal are separately pulverized (equivalent to only the third pulverizing step), mixed on a conveyor, and charged into a coke oven. Coke was also produced.

  The drum strength (DI) of the produced coke was measured. The drum strength (DI30 / 15) of the coke produced by the method of the present invention is 94.1, which is 0 in comparison with the drum strength (DI30 / 15) of the conventional coke as a comparative example being 94.0. Improved by 1%.

  It was found that if coke having the same strength as the conventional one is produced, the proportion of non-microcoking coal can be increased to about 82%, and the cost of coke can be reduced.

The schematic of one Embodiment of the coke manufacturing equipment of this invention. The graph which shows the particle size distribution of combination charcoal. The graph which shows the relationship between the classification particle size and coke manufacturing cost in a classification process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Coal yard 2 Coal yard 3 Sieve 4 1st grinder 5 1st compounding tank 6 2nd compounding tank 7 2nd compounding tank 8 2nd grinder 9 3rd grinder 10 3rd grinder a Sieve up b Sieve down

Claims (10)

  A classifying step for classifying a part of coal as a coke raw material into coal having a large particle size and coal having a small particle size, a first pulverizing step for pulverizing the coal having a large particle size, and the first pulverization It is processed by a first blending step of blending the coal treated in the step and the coal having a small particle diameter and a second pulverizing step of pulverizing the blended coal, and the remainder of the coal as the coke raw material is treated. Coke characterized by being charged in a coke oven after being treated by a second blending step to be blended and a third grinding step for grinding the blended coal together with the coal treated in the second grinding step. Manufacturing method. A method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X),
A classification step of classifying at least a part of the coal (X) into a coal having a large particle size and a coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, and the first pulverization After processing by the compounding process which mix | blends the coal processed by the process, the said small particle size coal, the remainder of coal (X), and the said coal (Y), and the 2nd grinding | pulverization process which grind | pulverizes this compounded coal A method for producing coke, which is charged in a coke oven.   A method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a large particle size. And a classification process for classifying the coal with a small particle diameter, a first pulverization process for pulverizing the coal with a large particle diameter, coal treated in the first pulverization process, coal with a small particle diameter and / or Or a first blending step of blending the remainder of the coal (X) and a second blending step of blending the coal (Y) by treating with a second grinding step of grinding the blended coal; The method for producing coke, wherein the coal (X) and the coal (Y) are charged into a coke oven after being treated in a third pulverization step of pulverizing the blended coal.   A method for producing coke using coal (X) having a high hardness and coal (Y) having a hardness lower than that of the coal (X), wherein at least a part of the coal (X) has a large particle size. A classification step of classifying the coal with a small particle size, a first pulverization step for pulverizing the coal with a large particle size, and a coal treated in the first pulverization step and a coal with a small particle size The first blending step of blending and the second blending step of treating the blended coal by the second pulverizing step and blending the remainder of the coal (X) and the coal (Y) separately A method for producing coke, wherein the coal (X) and the coal (Y) are charged into a coke oven after being treated in a third pulverization step of separately pulverizing the blended coal. A method for producing coke using coal (X ′) having a large amount of inert and coal (Y ′) having a smaller amount of inert than the coal (X ′),
A classification step of classifying at least a part of the coal (X ′) into a coal having a large particle size and a coal having a small particle size, a first pulverizing step of pulverizing the coal having a large particle size, By the blending step of blending the coal treated in the grinding step, the small particle size coal, the remainder of the coal (X ′) and the coal (Y ′), and the second grinding step of grinding the blended coal A method for producing coke, wherein the coke oven is charged after the treatment.   A method for producing coke using coal (X ′) having a large amount of inert and coal (Y ′) having a smaller amount of inert than the coal (X ′), wherein at least part of the coal (X ′) Is classified into a coal having a larger particle diameter and a coal having a smaller particle diameter than the coal, a first pulverizing process for pulverizing the coal having a larger particle diameter, and the first pulverizing process. It is processed by a first blending step of blending coal with the small particle size coal and / or the remainder of the coal (X ′) and a second pulverization step of pulverizing the blended coal, Y ′) is mixed with the second blending step and the blended coal is ground with a third grinding step, and the coal (X ′) and the coal (Y ′) are charged into the coke oven. A method for producing coke, characterized in that:   A method for producing coke using coal (X ′) having a large amount of inert and coal (Y ′) having a smaller amount of inert than the coal (X ′), wherein at least part of the coal (X ′) A classification step of classifying the coal into a coal with a large particle size and a coal with a small particle size, a first pulverization step of pulverizing the coal with a large particle size, the coal treated in the first pulverization step, and the particles It is processed by a first blending step for blending coal with a small diameter and a second grinding step for grinding the blended coal, and the remainder of the coal (X ′) and the coal (Y ′) are separated separately. The coke oven is charged with the coal (X ′) and the coal (Y ′) after being treated by the second blending step to be blended and the third grinding step for separately grinding the blended coal. A method for producing coke, characterized by:   The method for producing coke according to any one of claims 1 to 7, wherein classification is performed into coal having a particle size set within a range of 1 to 20 mm and having a large particle size and coal having a small particle size.   A classifier that classifies a part of coal as a coke raw material into coal having a large particle size and coal having a small particle size, a first pulverizer that pulverizes the coal having a large particle size, and the first pulverization A first blending tank for blending the coal treated in the mill with the coal having a small particle size, a second mill for grinding the coal blended in the first blending tank, and the coal as the coke raw material A second blending tank for blending the remainder, a third pulverizer for pulverizing the coal blended in the second blending tank, the coal treated by the second pulverizer, and the third pulverizer A coke production facility comprising a transporter for transporting the coal treated in step 1 to a coke oven.   10. The coke production facility according to claim 9, wherein the pulverization capacity of the first pulverizer is greater than that of the second pulverizer.

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