JP2010077332A - Manufacturing method of coke - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of coke comprising increasing a bulk density using a bulk density-increasing agent when raw material coal is charged into a coke oven that permits sufficient exhibition of performances of the bulk density-increasing agent to make the bulk density larger than before thereby enhancing productivity of coke. <P>SOLUTION: The manufacturing method of coke includes adding a bulk density-increasing agent to coal by means of a nozzle 8, subsequently crushing and conditioning the coal, then charging the coal into a coke oven 4 and dry-distilling the coal. Preferably, coal is crushed in 2 after the bulk density-increasing agent is added to coal, and the crushed coal is heated in a rotary conditioning apparatus 3 to decrease the water content. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method for producing coke by carbonizing coal using a coke oven, and more particularly to a method for producing coke using a coal bulk density improver.

  Various cokes represented by blast furnaces are manufactured by blending and pulverizing many brands of coal and then charging them into a coke oven. The charged coal is hot-distilled in the furnace to become coke.

  Conventionally, in order to produce high-quality coke with high strength, strong caking coal has been mainly used as a raw material. However, for reasons such as resource depletion, there is a demand for a method for producing coke in which coke quality does not deteriorate even if the blending ratio of strong caking coal is reduced, and various methods have been proposed.

  As one method for obtaining high-quality coke, it is conceivable to improve the bulk density of the coal charged into the coke oven. Since the coke oven is a constant volume reactor, coke productivity is improved by increasing the bulk density of the coal charge. As a method of improving the bulk density of coal charging, a method of pressing the raw coal charged in the coke oven (stamp charge), a method of granulating dry pulverized coal, and directing coal close packing in the coke oven There are methods. In addition, a method using a bulk density improver is known (see, for example, Patent Document 1 and Patent Document 2).

  A bulk density improver imparts a bulk density improving effect by imparting a slip accelerating action to coal when carbonizing the coal to produce coke. To be added. Surfactant as a bulk density improver is dissolved in a solvent and added to coal as a solution to reduce the surface tension of water adhering to the coal surface and increase the bulk density of the charged coal using lubricity. It is possible to produce high-quality coke with high productivity by using it for coal charged in a coke oven.

  By increasing the packing density of the coal charged into the coke oven in this way, it is possible to produce higher quality coke when using the same coal, and to produce the same quality coke. When manufacturing, cheaper coal can be used as a raw material.

On the other hand, as a method for obtaining high-quality coke, a method is known in which coke is produced using conditioned coal that has been dried so that the coal has a predetermined moisture content (for example, Patent Document 3, (See Patent Document 4). The method of using conditioned coal as a raw material for coke requires a large-scale equipment modification and the equipment cost is high, but it is possible to adjust large fluctuations in the moisture content of coal due to the weather, and coke production under certain conditions Can be performed. By using conditioned coal, the charging bulk density of the coal is improved, the productivity is improved, and it becomes possible to stably produce high-quality coke.
JP 2007-63420 A JP-A 61-28385 JP 2001-262156 A JP 2002-265955 A

  At present, a method for producing coke using conditioned coal that has been modified to a predetermined moisture and used after drying the coal to a specified moisture content, the bulk density improver is no longer used as coke feed coal. The method of adding and improving the bulk density is no longer performed, and the method using conditioned coal becomes the mainstream in the operation of producing coke.

  The use of the bulk density improver is limited in some cases, such as use in a factory that does not have humidity control coal production facilities, and treatment of generated dust in the humidity control coal production facilities.

  The background that the bulk density improver is less used in the coke production process is that the bulk density improving effect is small. If the bulk density improver and the raw material coal are not mixed uniformly, the effect of improving the bulk density will not be sufficiently exhibited. Therefore, even if a large effect can be obtained at the laboratory level, the bulk density improver is not practically effective. There is a problem that the density improvement effect is small. Using a mixing device to uniformly mix coal and a bulk density improver increases the equipment cost of coke production and also reduces productivity.

  Accordingly, an object of the present invention is a method for solving such problems of the prior art and improving the bulk density when charging raw coal into a coke oven using a bulk density improver, It is an object of the present invention to provide a method for producing coke that can sufficiently enhance the above-described performance and increase the bulk density more than before, thereby improving the coke productivity.

The features of the present invention for solving such problems are as follows.
(1) In a method for producing coke in which coal is charged into a coke oven and then carbonized,
A method for producing coke, comprising adding a bulk density improver to the coal, then conditioning the humidity, and charging the conditioned coal in a coke oven.
(2) The method for producing coke according to (1), wherein the humidity is controlled by heating in a rotary humidity control coal facility to reduce the water content.
(3) The method for producing coke according to (1) or (2), wherein after the bulk density improver is added to the coal, the coal is pulverized and humidity-controlled.

  According to the present invention, after the bulk density improver is added, the bulk density improver is dispersed in the entire coal by drying the coal while stirring the coal in a humidity control coal facility. The bulk density can be improved more than before.

  In addition, after adding a bulk density improver to the coal, the coal is pulverized and dried while stirring the coal in a humidity control coal facility, so that the bulk density improver is dispersed throughout the coal. With a small addition amount of the agent, the bulk density of the entire coal is improved, and the bulk density can be improved more than before.

  As a result, coke productivity can be improved. For this reason, it becomes possible to manufacture a higher quality coke and to use cheaper coal as a raw material.

  In the present invention, a method of adding a bulk density improver to coal and improving the bulk density of the coal when charging into the coke oven is used, but after adding the bulk density improver to the coal, the humidity of the coal is adjusted. Is what you do. In the present invention, as the humidity control equipment, a rotary humidity control capable of continuously drying a large amount of coal, called a rotary dryer with an indirect heating pipe, a rotary inclined tube dryer with a heat transfer pipe, or a rotary tube dryer. Use charcoal equipment.

  In addition, after adding the bulk density improver to the coal, by performing a humidity control step of adjusting the moisture content by heating and drying the coal with a rotary humidity control coal equipment, the bulk density improver in the coal Dispersibility is improved and sufficient mixing can be performed. And the effect that the surface tension of the water | moisture content adhering to coal by a bulk density improvement agent falls is exhibited to the maximum, and the bulk density of coal at the time of charging into a coke oven can be made high. Thus, coke is manufactured by charging coal in a coke oven with a high bulk density and subjecting it to dry distillation.

  It is preferable to add the bulk density improver to the coal before pulverizing the coal.

  After adding the bulk density improver to the coal, the coal is pulverized and dried while stirring the coal in a humidity control coal facility, so that the bulk density improver is dispersed throughout the pulverized coal. By adding a small amount of the density improver, the bulk density of the entire coal is improved, and the bulk density can be improved more than before. That is, by adding the bulk density improver to pulverize the coal, it is possible to further improve the mixability of the bulk density improver into the coal, and by drying the coal while stirring the coal in the humidity control equipment, The bulk density improver is dispersed throughout the pulverized coal, and the bulk density of the entire coal is improved with a small addition amount of the bulk density improver.

  FIG. 1 is a flow chart of raw coal charged into a coke oven, and is an explanatory view showing an embodiment of the present invention. Hereinafter, the present invention will be described more specifically with reference to FIG.

  The raw coal used for coke production is imported and landed, stored in a predetermined place in the field, transported to the coke production site, and pretreated. In this pretreatment step, raw material coal is mixed, pulverized, and humidity-controlled, and then introduced into a coke oven via a conveyor such as a belt conveyor, and dry distillation is performed. In some cases, blending is performed after pulverization. In FIG. 1, 1 is a compounding tank, in which various brands of coal are stored, cut out at a predetermined cutting ratio by a quantitative cutting device (not shown), mixed at a predetermined ratio, It is pulverized, charged into the humidity control equipment 3, dried (humidity control) in the humidity control equipment 3 so that the moisture content of the coal reaches a predetermined value, and supplied to the coke oven 4. It has become. 5 is a belt conveyor which conveys coal.

The humidity control facility 3 may be any facility that can heat and stir coal, and preferably heats coal while stirring. As described above, the humidity control facility 3 is a rotary dryer with an indirect heating pipe. Rotational humidity control equipment that can continuously dry a large amount of coal, called a rotary inclined tube dryer with a heat transfer tube or a rotary tube dryer, is used.
It is preferable that the humidity control equipment 3 has a rotation control device and controls the dry state according to the amount of coal and the water content. The moisture content of the dried coal is preferably 3 to 9% by mass. If it is less than 3% by mass, it becomes excessively dry, generating dust and the like, and hindering the charging of the coke oven, preferably 4% by mass or more and 9% by mass or less.

  In the present embodiment, in the above pretreatment step, a bulk density improver is added to the coal before the moisture conditioning treatment is performed before the coal is crushed. In FIG. 1, the bulk density improver in the bulk density improver tank 6 is sprayed from the nozzle 8 onto the coal on the belt conveyor 5 by using a pump 7. The coal to which the bulk density improver is added is pulverized by the pulverizer 2 and dried by the humidity control equipment 3 so that the bulk density improver and the coal are sufficiently mixed. In addition to the addition before crushing coal, it may be added and conditioned after crushing.

  A surfactant is preferably used as the bulk density improver. The surfactant improves the bulk density of the coal by reducing the surface tension of the water adhering to the surface of the raw coal particles and imparting lubricity between the coal particles. As the surfactant, for example, dialkylsulfosuccinic acid, polyoxyethylene alkyl ether and the like can be used.

  The amount of the bulk density improver added to the coal must be at least 0.05% by mass, and if it is less than 0.05% by mass, the effect of improving the bulk density by addition is not seen. Although the effect is high, the cost is high, so it is preferable that the upper limit is about 1% by mass of coal from the economical viewpoint. More preferably, 0.05-1 mass% of coal is added.

  A coal bulk density measurement test was performed using the same equipment as shown in FIG. 1 in which coal is pulverized and charged into a coke oven, and carbonized to produce coke.

  After adding 0.16% by mass of the raw material coal, polyoxyethylene alkyl ether sulfate as a bulk density improver, and pulverizing and measuring the bulk density when charged in a coke oven, no bulk density improver is added. Compared to the case, the bulk density was improved by 1.1%. In this case, the coal was not conditioned.

  Next, the effect of the bulk density improver when drying in a humidity control facility was performed so that the moisture content of coal was 6% by mass. Coke oven after adding 0.16% by mass of raw material coal, polyoxyethylene alkyl ether sulfate as bulk density improver, pulverizing, and adjusting humidity under conditions of 3-6 rpm using rotary humidity control equipment When the bulk density at the time of charging was measured, the bulk density was improved by 3.2% compared to the case where the humidity was adjusted without adding the bulk density improver.

  The results are shown in FIG.

  It was found that the bulk density was improved 3 times or more by adjusting the humidity after adding the bulk density improver.

Explanatory drawing which shows one Embodiment of this invention. The graph which shows the effect of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compounding tank 2 Crusher 3 Humidifier 4 Coke oven 5 Belt conveyor 6 Bulk density improver tank 7 Pump 8 Nozzle

Claims (3)

In the method for producing coke, in which coal is charged into a coke oven and carbonized,
A method for producing coke, comprising adding a bulk density improver to the coal, then conditioning the humidity, and charging the conditioned coal in a coke oven.   The method for producing coke according to claim 1, wherein the humidity is adjusted by heating in a rotary humidity control coal facility to reduce the water content.   The method for producing coke according to claim 1 or 2, wherein after adding a bulk density improver to the coal, the coal is pulverized and conditioned.

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