JPWO2010050332A1 - Method for producing coal caking filler - Google Patents

Abstract

A method for producing a coal-caking filler for addition to coal charged into a coke oven, wherein a distillation vapor containing low-boiling components generated from a distillation tower (10) is generated in a coke oven (1). The COG is returned to the generating COG line (2) for cooling and gas processing, and is processed together with the COG.

Description

  The present invention relates to a method for producing a coal-caking filler for addition to charging coal into a coke oven.

At steelworks, coke used in blast furnaces is produced in coke ovens. A coke oven is a large-scale furnace for carbonizing coal.
When the coal is charged into the coke oven, the moisture of the coal evaporates in the temperature rising process from room temperature to 100 ° C. When the temperature exceeds 300 ° C., the coal melts and expands, and when further heated, the coals are fused and consolidated. In this process, C, H, and the like contained in the coal are decomposed and combined to generate gas and coal tar, and semi-coke is generated.
When the temperature exceeds 500 ° C., solidification and shrinkage of semi-coke progress, and by 900 ° C., almost all of the semi-coke becomes coke.
The gas generated in the carbonization process is called COG (Coke Oven Gas, coke oven gas) and is used as an energy source in the steelworks. Coal tar is removed from the coke oven as a by-product.
The behavior of coal melting / expansion and fusion / consolidation varies greatly depending on the brand and type of coal. The property that coal coales with each other is called “caking”.
When coal with weak caking properties is dry distilled as it is, brittle coke is obtained, but when coal with strong caking properties is dry distilled, the whole is sufficiently fused and consolidated to obtain coke with high strength.
Steelworks consume a large amount of coke, and there is a need to reduce the cost of the coal used as the raw material.
Strong caking coal with strong caking properties is expensive because there are many inquiries as coke raw materials. Non-slightly caking coal with poor caking properties can produce only brittle, low-quality coke, but is inexpensive.
Therefore, techniques for producing higher quality, that is, strong coke, using inexpensive non-caking coal as a raw material have been studied.
As a technique for improving the quality of coke produced using non-slightly caking coal as a raw material, there is a method of increasing coal meltability and fluidity by adding coal caking filler.
Patent Document 1 discloses a method for producing high-strength coke by adding a heavy fraction obtained by removing a low-boiling light fraction from coal tar taken as a by-product from a coke oven to raw coal. ing.
Patent Document 2 discloses a method for producing a low-viscosity coal caking filler (caking aid) that separates and discharges low-boiling substances from coal tar. In this method, coal tar taken out as a by-product from the coke oven is blown from a conduit connected to the upper part of the distillation column, and steam is blown from a conduit connected to the lower part of the distillation column to remove low-boiling components in the coal tar. It is a method of removing. The coal tar blowing position and the steam blowing position are partitioned into two upper and lower chambers by a chimney tray, and the pressure in the distillation column is reduced to 6.7 to 26.7 kPa (50 to 200 Torr), The heating temperature is 170 to 200 ° C.

Japanese Patent Laid-Open No. 9-100473 Japanese Patent No. 3684063

In the conventional method for producing a coal caking filler disclosed in Patent Document 2, the pressure in the distillation column must be reduced to 6.7 to 26.7 kPa (50 to 200 Torr), such as a vacuum pump. The decompression equipment was required.
Further, a cooler for condensing and liquefying the distillation vapor containing the low boiling point components generated from the distillation tower was necessary.
Each of these facilities has a problem that the facility scale is large, the facility cost is expensive, and inspection and maintenance are not easy.
An object of the present invention is to provide a coal caking filler that can be produced at low cost from coal tar without newly installing a decompression equipment and a cooler that are large in equipment size and are not easily inspected and maintained. It is to provide a manufacturing method.

The present invention has been made to solve the above-described problems, and provides the following means.
(1) Coal tar taken out as a by-product from the coke oven is blown into the distillation column through a conduit connected to the upper part of the distillation column, and low-boiling components in the coal tar are removed to recover a heavy fraction. In the method for producing coal caking filler, distillation vapor containing low boiling point components generated from a distillation tower is returned to the generated COG line where COG generated in the coke oven is cooled and gas-treated, and processed together with COG. The manufacturing method of the coal caking filler characterized by the above-mentioned.
(2) Coal caking according to (1), which absorbs distilled vapor containing low-boiling components generated from a distillation tower by a suction blower provided in a generated COG line for cooling and gas treating COG generated in a coke oven. A method of manufacturing a filling material.
(3) The method for producing a coal-caking filler according to (1) or (2), wherein a distillation vapor containing a low-boiling component generated from a distillation tower is returned between a coke oven outlet and a COG gas cooler.
(4) The method for producing a coal caking filler according to any one of (1) to (3), wherein the pressure in the distillation column is 93.4 to 98.6 kPa and the heating temperature is 180 to 210 ° C.

  According to the present invention, it is possible to produce a coal caking filler from coal tar at a low cost without newly installing a decompression equipment or a cooler whose equipment scale is large and inspection and maintenance is not easy. A method can be provided.

  Drawing 1 is a figure showing an example of an embodiment of a manufacturing method of coal caking filler according to the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
In FIG. 1, coking coal is charged into a coke oven 1 to produce coke. Inside the coke oven 1, coal is carbonized into coke. During the temperature raising process, C and H contained in the coal are decomposed and combined to generate gas and coal tar as by-products.
The generated high temperature gas (COG) is sent to the COG gas cooler such as the primary cooler 3 and the direct cooler 4 through the generated COG line 2 and cooled by using seawater or the like. Further, the blower 5 is sent to a gas purification processing line (not shown) such as a naphthalene scrubber, ammonia scrubber, benzol scrubber, etc. (not shown) in the subsequent stage, purified and used as an energy source of the steelworks.
The generated COG line 2 is provided with a decanter 6 and a super decanter 7 for recovering coal tar. The collected coal tar is collected in the tar tank 8 and shipped.
In this invention, a coal caking filler is manufactured using a part of collect | recovered coal tar.
Coal tar in the tar tank 8 is dehydrated tar having a water content of 3% or less, and is sent to the distillation column 10 by the pump 9.
The heat exchanger 11 on the path is a device for heating the dehydrated tar by heat exchange with a high-temperature heavy fraction recovered from the distillation column 10. The heater 12 on the path is an apparatus for heating the dehydrated tar using a part of the high-temperature and high-pressure steam blown into the distillation column 10. The dehydrated tar is heated to about 200 ° C. by passing through the heat exchanger 11 and the heater 12.
The heated dehydrated tar is blown into the distillation column 10 through a conduit 17 connected to the upper portion of the distillation column 10. The inside of the distillation column 10 is divided into multiple stages by the partition wall 13 to enhance the distillation effect.
High-temperature and high-pressure steam is blown into the distillation column 10 from the conduit 18 connected to the lower part of the distillation column 10, and low boiling components in the coal tar are evaporated to form distillation vapor. A conduit connected to the upper end of the distillation column 10. 19 is taken out.
The heavy fraction from which the low boiling point components in the coal tar have been removed is collected in the lower part of the distillation column 10 and taken out to the tank 15 by the pump 14. The retained heat of the heavy fraction is used by the heat exchanger 11 to heat the dehydrated tar.
As described above, coal tar is distilled inside the distillation column 10, and the heavy fraction is used as a coal caking filler.
Distilled vapor containing a low-boiling component absorbs naphthalene in the naphthalene absorption tower 16 and then returns to the generation COG line 2 without condensing.
The generated COG line 2 is connected to a gas purification processing line such as a primary cooler 3 or a direct cooler 4 or other gas purification equipment such as a blower 5, a naphthalene scrubber, an ammonia scrubber, or a benzol scrubber (not shown), and thus has a low boiling point. Distilled vapor containing the components is cooled and gas purified along with COG.
In the present invention, the distillation vapor containing the low boiling point component generated from the distillation column 10 is returned to the generated COG line 2 of the coke oven 1 without being condensed and processed together with the COG. There is no need to install equipment or a cooler.
In the present invention, the inside of the distillation column 10 is depressurized using the blower 5 arranged in the subsequent stage of the generation COG line 2, and the pressure inside the distillation column 10 is 93.4 to 98.6 kPa (700 to 740 Torr). Therefore, when compared with the method disclosed in Patent Document 2 in which the pressure in the distillation column is reduced to 6.7-26.7 kPa (50-200 Torr) and the heating temperature is 170-200 ° C. Needs to be set to a slightly higher 180-210 ° C. Therefore, although the energy cost required for the distillation operation in the distillation column 10 is increased, the total cost can be reduced because the effect of reducing the equipment cost is greater.
For this reason, according to the present invention, a coal caking filler can be manufactured at low cost from coal tar without newly installing a decompression facility or a cooler that has a large facility scale and is not easily inspected and maintained.
The quality of the coal caking filler obtained by the method of the present invention is equivalent to that of the conventional product. When adding 1 to 4% by mass of coal caking filler to non-slightly caking coal and charging into coke oven 1, the quality (strength) of the resulting coke is made from strong caking coal Can be improved to the same level.
For this reason, it becomes possible to increase the mixing ratio of inexpensive non-caking coal as a coke raw material, and the economic effect is extremely large.
As mentioned above, although preferred embodiment of this invention was described, said embodiment is an illustration and this invention should not be limited and limited to this. It is obvious that those having ordinary knowledge in the technical field to which the present invention pertains can conceive various changes and modifications within the scope of the technical idea of the present invention. It is understood that it belongs to the technical scope of the invention.

According to the present invention, a coal caking filler can be produced at low cost from coal tar without newly installing a decompression equipment or a cooler that has a large equipment scale and is not easily inspected and maintained. The manufacturing method of can be provided.
Further, the quality of the coal caking filler obtained by the method of the present invention is equivalent to that of the conventional product, and 1 to 4% by mass of the coal caking filler is added to the non-fine caking coal and the coke oven is loaded. By entering, the quality of the obtained coke can be improved to the same level as the case where strong caking coal is used as a raw material.
Therefore, the present invention has great industrial applicability.

1 Coke Oven 2 Generated COG Line 3 Primary Cooler 4 Direct Cooler 5 Blower 6 Decanter 7 Super Decanter 8 Tar Tank 9 Pump 10 Distillation Tower 11 Heat Exchanger 12 Heater 13 Bulkhead 14 Pump 15 Tank 16 Naphthalene Absorption Tower 17 Conduit 18 Conduit 19 conduit

  The present invention relates to a method for producing a coal-caking filler for addition to charging coal into a coke oven.

  At steelworks, coke used in blast furnaces is produced in coke ovens. A coke oven is a large-scale furnace for carbonizing coal.

  When the coal is charged into the coke oven, the moisture of the coal evaporates in the temperature rising process from room temperature to 100 ° C. When the temperature exceeds 300 ° C., the coal melts and expands, and when further heated, the coals are fused and consolidated. In this process, C, H, and the like contained in the coal are decomposed and combined to generate gas and coal tar, and semi-coke is generated.

  When the temperature exceeds 500 ° C., solidification and shrinkage of semi-coke progress, and by 900 ° C., almost all of the semi-coke becomes coke.

  The gas generated in the carbonization process is called COG (Coke Oven Gas) and is used as an energy source in the steelworks. Coal tar is removed from the coke oven as a by-product.

  The behavior of coal melting / expansion and fusion / consolidation varies greatly depending on the brand and type of coal. The property that coal coales with each other is called “caking”.

  When coal with weak caking properties is dry distilled as it is, brittle coke is obtained, but when coal with strong caking properties is dry distilled, the whole is sufficiently fused and consolidated to obtain coke with high strength.

  Steelworks consume a large amount of coke, and there is a need to reduce the cost of the coal used as the raw material.

  Strong caking coal with strong caking properties is expensive because there are many inquiries as coke raw materials. Non-slightly caking coal with poor caking properties can produce only brittle, low-quality coke, but is inexpensive.

  Therefore, techniques for producing higher quality, that is, strong coke, using inexpensive non-caking coal as a raw material have been studied.

  As a technique for improving the quality of coke produced using non-slightly caking coal as a raw material, there is a method of increasing coal meltability and fluidity by adding coal caking filler.

  Patent Document 1 discloses a method for producing high-strength coke by adding a heavy fraction obtained by removing a low-boiling light fraction from coal tar taken as a by-product from a coke oven to raw coal. ing.

  Patent Document 2 discloses a method for producing a low-viscosity coal caking filler (caking aid) that separates and discharges low-boiling substances from coal tar. In this method, coal tar taken out as a by-product from the coke oven is blown from a conduit connected to the upper part of the distillation column, and steam is blown from a conduit connected to the lower part of the distillation column to remove low-boiling components in the coal tar. It is a method of removing. The coal tar blowing position and the steam blowing position are partitioned into two upper and lower chambers by a chimney tray, and the pressure in the distillation column is reduced to 6.7 to 26.7 kPa (50 to 200 Torr), The heating temperature is 170 to 200 ° C.

Japanese Patent Laid-Open No. 9-100473 Japanese Patent No. 3684063

  In the conventional method for producing a coal caking filler disclosed in Patent Document 2, the pressure in the distillation column must be reduced to 6.7 to 26.7 kPa (50 to 200 Torr), such as a vacuum pump. The decompression equipment was required.

  Further, a cooler for condensing and liquefying the distillation vapor containing the low boiling point components generated from the distillation tower was necessary.

  Each of these facilities has a problem that the facility scale is large, the facility cost is expensive, and inspection and maintenance are not easy.

  An object of the present invention is to provide a coal caking filler that can be produced at low cost from coal tar without newly installing a decompression equipment and a cooler that are large in equipment size and are not easily inspected and maintained. It is to provide a manufacturing method.

  The present invention has been made to solve the above-described problems, and provides the following means.

(1) Coal tar taken out as a by-product from the coke oven is blown into the distillation column through a conduit connected to the upper part of the distillation column, and low-boiling components in the coal tar are removed to recover a heavy fraction. In the production method of coal caking filler,
The pressure in the distillation column is 93.4 to 98.6 kPa, the heating temperature is 180 to 210 ° C.,
Production of coal caking filler characterized by returning distilled vapor containing low boiling point components generated from a distillation tower to COG line for cooling and gas treatment of COG generated in coke oven and processing with COG Method.

  (2) The coal according to (1), wherein CO vapor generated in a coke oven is cooled and gas-treated, and the suction vapor provided in the generation COG line absorbs the distillation vapor containing low boiling point components generated from the distillation tower. Method for producing caking filler.

(3) The method for producing a coal-caking filler according to (1) or (2) above, wherein a distillation vapor containing a low-boiling component generated from a distillation tower is returned between the coke oven outlet and the COG gas cooler. .

  According to the present invention, it is possible to produce a coal caking filler from coal tar at a low cost without newly installing a decompression equipment or a cooler whose equipment scale is large and inspection and maintenance is not easy. A method can be provided.

It is a figure which shows an example of embodiment of the manufacturing method of the coal caking filler based on this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG.

  In FIG. 1, coking coal is charged into a coke oven 1 to produce coke. Inside the coke oven 1, coal is carbonized into coke. During the temperature raising process, C and H contained in the coal are decomposed and combined to generate gas and coal tar as by-products.

  The generated high temperature gas (COG) is sent to the COG gas cooler such as the primary cooler 3 and the direct cooler 4 through the generated COG line 2 and cooled by using seawater or the like. Further, the blower 5 is sent to a gas purification processing line (not shown) such as a naphthalene scrubber, ammonia scrubber, benzol scrubber, etc. (not shown) in the subsequent stage, purified and used as an energy source of the steelworks.

  The generated COG line 2 is provided with a decanter 6 and a super decanter 7 for recovering coal tar. The collected coal tar is collected in the tar tank 8 and shipped.

  In this invention, a coal caking filler is manufactured using a part of collect | recovered coal tar.

  Coal tar in the tar tank 8 is dehydrated tar having a water content of 3% or less, and is sent to the distillation column 10 by the pump 9.

  The heat exchanger 11 on the path is a device that heats the dehydrator by heat exchange with the high-temperature heavy fraction recovered from the distillation column 10. The heater 12 on the path is an apparatus for heating the dehydrated tar using a part of the high-temperature and high-pressure steam blown into the distillation column 10. The dehydrated tar is heated to about 200 ° C. by passing through the heat exchanger 11 and the heater 12.

  The heated dehydrated tar is blown into the distillation column 10 through a conduit 17 connected to the upper portion of the distillation column 10. The inside of the distillation column 10 is divided into multiple stages by the partition wall 13 to enhance the distillation effect.

  High-temperature and high-pressure steam is blown into the distillation column 10 from the conduit 18 connected to the lower part of the distillation column 10, and low boiling components in the coal tar are evaporated to form distillation vapor. A conduit connected to the upper end of the distillation column 10. 19 is taken out.

  The heavy fraction from which the low boiling point components in the coal tar have been removed is collected in the lower part of the distillation column 10 and taken out to the tank 15 by the pump 14. The retained heat of the heavy fraction is used by the heat exchanger 11 to heat the dehydrated tar.

  As described above, coal tar is distilled inside the distillation column 10, and the heavy fraction is used as a coal caking filler.

  Distilled vapor containing a low-boiling component absorbs naphthalene in the naphthalene absorption tower 16 and then returns to the generation COG line 2 without condensing.

  Since the generated COG line 2 is connected to a gas purification processing line such as a primary cooler 3 or a direct cooler 4 or a COG gas cooler, a blower 5, a naphthalene scrubber, an ammonia scrubber, a benzol scrubber or the like (not shown), it has a low boiling point. Distilled vapor containing the components is cooled and gas purified along with COG.

  In the present invention, the distillation vapor containing the low boiling point component generated from the distillation column 10 is returned to the generated COG line 2 of the coke oven 1 without being condensed and processed together with the COG. There is no need to install equipment or a cooler.

  In the present invention, the inside of the distillation column 10 is depressurized using the blower 5 arranged in the subsequent stage of the generation COG line 2, and the pressure inside the distillation column 10 is 93.4 to 98.6 kPa (700 to 740 Torr). Therefore, when compared with the method disclosed in Patent Document 2 in which the pressure in the distillation column is reduced to 6.7-26.7 kPa (50-200 Torr) and the heating temperature is 170-200 ° C. Needs to be set to a slightly higher 180-210 ° C. Therefore, although the energy cost required for the distillation operation in the distillation column 10 is increased, the total cost can be reduced because the effect of reducing the equipment cost is greater.

  For this reason, according to the present invention, a coal caking filler can be manufactured at low cost from coal tar without newly installing a decompression facility or a cooler that has a large facility scale and is not easily inspected and maintained.

  The quality of the coal caking filler obtained by the method of the present invention is equivalent to that of the conventional product. When adding 1 to 4% by mass of coal caking filler to non-slightly caking coal and charging into coke oven 1, the quality (strength) of the resulting coke is made from strong caking coal Can be improved to the same level.

  For this reason, it becomes possible to increase the mixing ratio of inexpensive non-caking coal as a coke raw material, and the economic effect is extremely large.

  As mentioned above, although preferred embodiment of this invention was described, said embodiment is an illustration and this invention should not be limited and limited to this. It is obvious that those having ordinary knowledge in the technical field to which the present invention pertains can conceive various changes and modifications within the scope of the technical idea of the present invention. It is understood that it belongs to the technical scope of the invention.

  According to the present invention, a coal caking filler can be produced at low cost from coal tar without newly installing a decompression equipment or a cooler that has a large equipment scale and is not easily inspected and maintained. The manufacturing method of can be provided.

  Further, the quality of the coal caking filler obtained by the method of the present invention is equivalent to that of the conventional product, and 1 to 4% by mass of the coal caking filler is added to the non-fine caking coal and the coke oven is loaded. By entering, the quality of the obtained coke can be improved to the same level as the case where strong caking coal is used as a raw material.

  Therefore, the present invention has great industrial applicability.

DESCRIPTION OF SYMBOLS 1 Coke oven 2 Generation | occurrence | production COG line 3 Primary cooler 4 Direct cooler 5 Blower 6 Decanter 7 Super decanter 8 Tar tank 9 Pump 10 Distillation tower 11 Heat exchanger 12 Heater 13 Bulkhead 14 Pump 15 Tank 16 Naphthalene absorption tower 17 Pipe 18 Pipe 19 conduit

Claims (4)

  Coal tar extracted as a by-product from the coke oven is blown into the distillation column through a conduit connected to the upper part of the distillation column, and low-boiling components in the coal tar are removed to recover a heavy fraction. In the method for producing a binding filler, a distillation vapor containing a low boiling point component generated from a distillation tower is returned to a generated COG line for cooling and gas treating COG generated in a coke oven, and is treated with COG. A method for producing coal caking filler.   2. The coal caking filler according to claim 1, wherein CO vapor generated in the coke oven is cooled and gas-treated, and the suction vapor provided in the generating COG line absorbs the distillation vapor containing low-boiling components generated from the distillation tower. Manufacturing method.   The method for producing a coal-caking filler according to claim 1 or 2, wherein a distillation vapor containing a low-boiling component generated from the distillation tower is returned between the outlet of the coke oven and the COG gas cooler.   The method for producing a coal-caking filler according to any one of claims 1 to 3, wherein the pressure in the distillation column is 93.4 to 98.6 kPa and the heating temperature is 180 to 210 ° C.

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