KR20110121726A - Process for producing blast furnace coke - Google Patents

Abstract

In the method for producing blast furnace coke, the coal-based liquid caking additive is formed at a temperature equal to or more than a liquefaction temperature where the viscosity of the coal-based liquid caking additive becomes 100 cP and a liquefaction temperature such that the viscosity of the petroleum-based solid caking additive becomes 100 cP. It warms up, melt | dissolves the said solid petroleum caking additive in the said liquid caking additive of the said coal system, prepares a mixed caking additive, mixes raw coal with the said mixing caking additive, prepares a mixed raw material, and dry-mixes the said mixed raw material. .

Description

Production method of blast furnace coke {PROCESS FOR PRODUCING BLAST FURNACE COKE}

The present invention relates to a method for producing blast furnace coke using a caking additive.

This application claims priority in April 9, 2009 based on Japanese Patent Application No. 2009-094521 for which it applied to Japan, and uses the content for it here.

Even if the use of low quality raw coal (non-coking coal and non-coking coal) is increased, high strength blast furnace coke is manufactured at low cost.The raw coal is mixed without liquefying the solid caking material, charged into the coke oven and dried. The method is proposed (patent document 1).

In the manufacturing method of the blast furnace coke of the said patent document 1, as shown to FIG. 4A, the raw coal (coal) 1 is grind | pulverized by predetermined | prescribed particle size by the grinder 2, and is sent to the kneading machine 3 Lose. On the other hand, the solid caking additive 4 is grain-sorted by the sizing machine 5 containing a grinder to a predetermined particle size structure (50 mass% or more of fine particles less than 3 mm in diameter), and kneading machine ( 3) is kneaded with the raw coal 1. In this kneader 3, the solid caking additive 4 similar in particle size structure to the raw coal 1 is mixed. For example, this raw coal 1 has a particle size constitution in which coal particles having a particle diameter of less than 3 mm are 75 to 80 mass%. Moreover, the coal 1 which mix | blended the solid caking additive 4 is sent from the kneading machine 3 to the coke oven 6, and the coke 7 is manufactured.

Thus, since the particle size structure of the raw coal 1 and the solid caking material 4 are similar, the solid caking material 4 is uniformly dispersed in the coal particles, so that the raw coal 1 and the solid caking material 4 are dispersed. The contact area of is increased. Therefore, an ideal contact form is obtained between the raw coal 1 and the solid caking additive 4, so that the coke strength can be increased.

In addition, as shown in FIG. 4B, it is also proposed to add a liquid caking additive 8 such as coal tar to the pulverized coal 1.

Japanese Patent Application Publication No. 2007-002052

As a caking additive, tar, a pitch, and a petroleum caking additive are used, for example. It is preferable that the caking additive which is liquid at ordinary temperature such as tar is usually kneaded uniformly with raw coal. In addition, it is preferable that the caking additive which is solid at ordinary temperature, such as pitch, is usually kneaded with raw coal after heating to a liquefaction point or more and liquefying.

As mentioned above, as a caking additive, a solid caking additive and a liquid caking additive are known. As a caking additive, this inventor paid attention to the solid caking additive of the low softening point which is petroleum heavy residues, such as asphalt, for example.

This low softening point solid caking additive has a viscosity of 10000 cP or more at normal temperature, for example, as shown by data A of FIG. 3, and can be handled as a solid. However, when the solid caking additive is atomized using a grinder or the like as in Patent Literature 1, the viscosity of the solid caking additive decreases due to the heat generated during the grinding, and thus it is difficult to handle as a solid. Therefore, the solid caking additive of the low softening point is unsuitable for atomization.

It is also conceivable to liquefy the solid caking additive of low softening point by heating. However, as shown in FIG. 3, in order to make viscosity (cP) below 100 cP which is a reference | standard of liquid liquefaction (after-mentioned), it is necessary to heat the solid caking additive of a low softening point to 230 degreeC or more using a heat source. However, since the heating temperature of 230 degreeC cannot be obtained by normal industrial low pressure steam, a heat source separate from the said heat source is needed, and cost increases.

This invention is made | formed in view of such a viewpoint, and an object of this invention is to provide the manufacturing method of the blast furnace coke which can improve coke strength and reduce expansion pressure. Moreover, an object of this invention is to provide the manufacturing method of the blast furnace coke which can use the solid caking additive of the low softening point which is difficult to handle when grind | pulverizing as caking additive.

The gist of the present invention is as follows.

(1) A method for producing blast furnace coke, wherein the liquid point of the coal system is at a temperature equal to or higher than the liquefaction temperature at which the viscosity of the coal-based liquid caking additive is 100 cP and at a temperature below the liquefaction temperature at which the viscosity of the petroleum solid caking additive is 100 cP. Warm the binder, dissolve the petroleum-based solid binder in the coal-based liquid binder, prepare a mixed binder, mix raw coal with the mixed binder, prepare a mixed raw material, and prepare the mixed raw material. Carbonize it.

(2) In the method for producing blast furnace coke according to (1), the petroleum-based solid caking additive may have a softening point of 180 ° C. or less.

(3) In the method for producing blast furnace coke according to the above (1), the petroleum-based solid caking additive may be an asphalt pitch.

(4) Coal tar may be sufficient as the said liquid caking additive of the said coal type | system | group in the manufacturing method of the blast furnace coke of said (1).

(5) In the manufacturing method of the blast furnace coke as described in said (1), the heating temperature of the said liquid caking additive of the said coal system may be 150 degrees C or less.

(6) In the manufacturing method of the blast furnace coke as described in said (1), the viscosity of the said mixed caking additive in the said temperature may be 100 cP or less.

(7) In the method for producing blast furnace coke according to the above (1), the raw coal may be fine coal.

(8) In the method for producing blast furnace coke according to the above (7), the pulverized coal may be obtained by pulverizing coal and then classifying it.

According to the present invention, the coke strength was improved and the expansion pressure could be suppressed by adding the liquid mixed caking material in which the coal-based liquid caking material and the petroleum-based solid caking material was mixed to the raw coal.

In addition, according to the present invention, by dissolving a petroleum-based solid binder such as asphalt in a coal-based liquid binder such as coal tar, which is heated, using a commercial low pressure steam for industrial use of the solid binder of low softening point industrially You can handle it.

1 is a block diagram showing a first embodiment of a method for producing blast furnace coke according to the present invention.
It is a block diagram which shows 2nd Embodiment of the manufacturing method of the blast furnace coke which concerns on this invention.
It is a figure which shows the relationship between the temperature and the viscosity (cP) of a caking additive.
It is a block diagram which shows the conventional manufacturing method of blast furnace coke.
4B is a block diagram showing a conventional method for producing blast furnace coke.

EMBODIMENT OF THE INVENTION Preferred embodiment of this invention is described, referring an accompanying drawing below.

[First Embodiment]

1 is a block diagram showing a first embodiment of a method for producing blast furnace coke according to the present invention.

In FIG. 1, coal 1 which is raw coal of coke is grind | pulverized with the grinder 2, and it supplies to the kneading machine 3. As shown in FIG. In addition, the coal caking liquid 8 is put in the heating container 12. This heating container 12 is heated by heaters, such as a heating coil to which normal industrial low pressure steam is supplied. The temperature of the coal-based liquid caking additive 8 in the heating container 12 is equal to or more than the liquefaction temperature of the liquid caking additive 8 and below the liquefaction temperature of the petroleum-based solid caking additive 11. This heating temperature is 140 degreeC, for example. Therefore, in the heating container 12, the liquid caking additive 8 exists as a liquid. In addition, in this invention, the softening point is measured by JISK2531. For example, this softening point can be measured by ASTM D36, and can also be converted into the softening point of JISK2531. The temperature at which the viscosity becomes 100 cP is defined as a liquefaction temperature, and the state (solid or liquid) of the caking additive is determined based on the viscosity (0.1 Pa · s) of 100 cP.

In addition, a mass of petroleum-based solid caking additive 11 is introduced into a heating container 12 containing the liquid caking additive 8, and the solid caking additive 11 is dissolved to dissolve the liquid caking additive 13. To prepare. The mixed caking additive 13 is kneaded with the coal 1 pulverized in the kneader 3 to prepare a mixed raw material. The coal 1 (mixed raw material) mixed with the mixed caking additive 11 is supplied to the coke oven 6, and the coal 1 (mixed raw material) is carbonized by the coke oven 6 to coke 7 Are manufactured.

The petroleum-based solid caking additive 11 is, for example, asphalt pitch, petroleum solvent deasphalted asphalt, petroleum heavy oil, and petroleum pitch. In particular, as the petroleum-based solid caking additive 11, an asphalt pitch as a heavy oil residue in crude oil refining is suitably used. The petroleum-based solid caking additive 11 may be a caking additive which processed the asphalt pitch.

Moreover, the coal caking liquid 8 is tar (coal tar), tar heavy oil, coal tar pitch, and lead pitch, for example. In particular, tar (coal tar) is suitably used as the coal caking additive 8. The coal caking additive 8 may be a caking additive obtained by processing tar (coal tar).

In FIG. 3, the relationship between temperature and the viscosity of each caking additive is shown as an example. Solid caking additive A (data A in FIG. 3) of a low softening point is an asphalt pitch. Liquid caking additive B (data B in FIG. 3) is coal tar. Liquid caking additive C (data C in FIG. 3) is neutralized coal tar from which hard content of coal tar was removed by distillation.

In addition, mixed caking additive M1 (data M1 in FIG. 3) is obtained by melt | dissolving solid caking additive A in the liquid caking additive C in the mass ratio of 3 to 1. Mixed caking additive M2 (data M2 in FIG. 3) is obtained by dissolving solid caking additive A in the liquid caking additive B at a mass ratio of 3: 1. Mixed caking additive M3 (data M3 in FIG. 3) is obtained by dissolving solid caking additive A in the liquid caking additive B at a mass ratio of 1: 1.

As shown in FIG. 3, in order to make the viscosity of the solid caking additive A 100 cP or less, it is necessary to heat solid caking additive A to the temperature of 230 degreeC or more. Therefore, in order to liquefy the solid caking additive A alone, as described above, a dedicated heat source is required, and the cost increases. In addition, if solid caking additive A of the liquid state heated at high temperature is added to coal, solid caking additive A will harden | cure by temperature fall and will not mix uniformly with coal. Therefore, it is necessary to heat the kneader 3 as a whole at the temperature more than the liquefaction temperature which becomes the viscosity of the solid caking additive A 100 cP or less, and costs increase.

On the other hand, the viscosity of liquid caking additives B and C is 100 cP or less at 100 degrees C or less. In addition, as shown by M1, M2, and M3 in FIG. 3, the viscosity of a mixed caking additive is 140 degreeC by mixing the solid caking additive A which cannot be liquefied alone at 140 degrees C or less with liquid caking additive B or C. Can be lowered to 100 cP or less. Therefore, when the lump of solid caking additive A is thrown into the liquid caking additive B or C of the heating container 12 heated at 140 degreeC, solid caking additive A will melt | dissolve. That is, the coal-based liquid caking additive 8 in the heating container 12 is heated to a temperature below the liquefaction temperature of the solid caking additive 11 of the petroleum-based low softening point and above the liquefaction temperature of the coal-based liquid caking additive 8 The solid caking additive 11 of low softening point melt | dissolves by inject | pouring the solid caking additive 11 of low softening point into the liquid caking additive 8 in the heating container 12.

It is preferable that the heating temperature of the liquid caking additive 8 of the coal system in this heating container 12 is 150 degrees C or less. In this case, the viscosity of the coal type liquid caking additive 8 in the heating container 12 is 100 cP or less. In addition, when the dissolution rate of the petroleum-based solid caking additive 11 is taken into consideration, the temperature of the coal-based liquid caking additive 8 is preferably 60 ° C or higher. In addition, even when the petroleum-based solid caking additive 11 is added, the temperature of the coal-based liquid caking additive 8 is maintained at a predetermined value by maintaining the temperature of the heating vessel 12 at a constant value. Therefore, the temperature of the mixed caking additive 13 is the same as the temperature of the liquid caking additive 8. At this temperature, the viscosity of the mixed caking additive is preferably 100 cP or less.

In addition, the petroleum-based solid caking additive 11 preferably has a softening point of 180 ° C. or lower in order to dissolve efficiently in the coal caking liquid caking additive 8. In this case, the temperature (liquidation temperature) at which the viscosity of the petroleum-based solid caking additive 11 is 100 cP is 350 ° C. or less. The temperature (liquefaction temperature) at which the viscosity of the petroleum-based solid caking additive 11 becomes 100 cP or less may be 60 ° C. or higher in consideration of manufacturing conditions such as fractionation. Further, the petroleum-based solid binder 11 is dissolved in the coal-based liquid binder 8 so that the temperature at which the viscosity of the mixed binder 13 becomes 100 cP is 150 ° C. or lower, so that the mixed binder 13 is mixed. It is preferable to prepare. In addition, when the viscosity of the coal caking additive 8 is taken into consideration, the temperature at which the viscosity of the mixed caking additive 13 becomes 100 cP or less may be 40 ° C. or higher. Moreover, it is preferable that the addition rate of all the caking additives (mixing caking additive) in coal (mixed raw materials) is 0.5 mass% or more and 10 mass% or less.

In the first embodiment of the present invention, by adding the mixed caking additive 13 to the atomized coal 1, the amount per unit amount of the caking additive compared to the case where only the solid caking additive 11 is added to the coal 1 The increase amount of coke strength can be improved significantly, and an expansion pressure can also be reduced. Moreover, the solid caking additive of a petroleum low softening point can be used, without involving difficulty of handling.

It is thought that such an improvement effect of coke strength (improvement of the increase amount of coke strength per unit amount of a caking additive) arises as follows. Petroleum caking additives (caking additives of low softening point) are hardly compatible with coal particles, because the chemical structure is significantly different from coal particles. However, petroleum-based solid binders can be infiltrated between coal particles by accommodating petroleum-based binders with coal-based binders (liquid binders) that are easily compatible with coal particles. Therefore, by dissolving the petroleum-based solid binder in the coal-based liquid binder, the solid binder is very well dispersed between the coal particles. Coal particles are efficiently bonded by this petroleum solid caking additive and coal liquid caking additive, and the above-mentioned improvement effect of coke strength arises.

In addition, when the solid caking additive in the solid state is atomized and dispersed in the gap of the coal particles, sufficient coke strength improvement effect corresponding to the addition amount of the solid caking additive is not obtained. However, in the first embodiment of the present invention, sufficient effect of improving coke strength can be obtained by dissolving a petroleum-based solid binder in a coal-based liquid binder (binder).

In the first embodiment of the present invention, not only the coke strength was improved but also the expansion pressure was largely suppressed. As described above, since the solid caking additive could be sufficiently dispersed between the coal particles, it is considered that the expansion pressure was largely suppressed.

Second Embodiment

It is a block diagram which shows 2nd Embodiment of the manufacturing method of the blast furnace coke which concerns on this invention.

In this 2nd Embodiment, the liquid mixed caking additive 13 is prepared by putting the lump of the solid caking additive 11 in the liquid caking additive 8 in the heating container 12 similarly to 1st Embodiment. . However, the coal 1 crushed by the crusher 2 is classified into the pulverized coal 15 and the granulated coal 16 in the dry classifier 14. This pulverized coal 15 is supplied to the kneader 3, and the mixing caking additive 13 is added to this kneader 3. In the kneader 13, the pulverized coal 15 and the mixed caking additive 13 are kneaded (mixed) to prepare a mixed raw material. In addition, the granulated coal 16 is added to the pulverized coal 15 (mixed raw material) mixed with the mixed caking additive 13 and sent to the coke oven 6. The coke 7 is manufactured by distilling the pulverized coal 15 and the coal briquettes 16 from the coke oven 6. Also in this case, coke strength could be improved and the expansion pressure could be reduced. Thus, pulverized coal may be sufficient as the raw coal to mix with a mixed caking additive. In addition, this pulverized coal may be obtained by pulverizing coal and classifying it. In addition, granulated coal does not need to be directly mixed with the mixed caking additive, but may be mixed with the above-described mixed raw materials.

That is, the method common to at least 1st Embodiment and 2nd Embodiment mentioned above is as follows. The coal-based liquid binder is heated to a temperature above the liquefaction temperature of the coal-based liquid binder and also below the liquefaction temperature of the petroleum-based solid binder. Thereafter, the petroleum-based solid binder is dissolved in the coal-based liquid binder to prepare a mixed binder. After mixing this mixed caking additive and raw coal, and preparing a mixed raw material, this mixed raw material is dried and coke is manufactured.

By the method mentioned above, coke strength can increase and the yield of coke can be improved. In addition, the expansion pressure of the raw coal charged into the coke oven is suppressed, so that the load on the coke oven can be reduced. In addition, it is easy to handle the low-softening point solid caking material, which has been difficult to use industrially, and the caking properties of the solid caking material can be utilized to the maximum.

Example

In Table 1, petroleum-based solid binders A1 to A3 and coal-based liquid binders B and C are shown. Petroleum-based solid binders A1 to A3 in Table 1 have a low softening point of 180 ° C or lower. In Table 2, the raw material conditions of coke of 1st-7th Example and the 1st-7th comparative example, and the coke manufacturing result, such as coke strength and expansion pressure, are shown. In Examples 1-7, the lump of petroleum-based solid binder A1, A2, or A3 shown in Table 1 was melt | dissolved in the liquid binder B or C of coal type system 100 degreeC-150 degreeC, and the mixed binder was obtained. . In addition, this mixed caking additive was added to the raw coal. In the second comparative example and the fourth to seventh comparative examples, petroleum-based solid binder A1 is pulverized and used. After mixing the raw materials of coke shown in Table 2, coke was manufactured by distilling.

In addition, the raw coal b in Table 2 is a coal blend whose volatile matter (VM) is 27.0% and the total expansion coefficient (TD) is 70%. Here, volatile matter (VM) is calculated | required by the volatile matter quantification method of JIS M 8812 "industrial analysis method of coal and coke." In addition, total expansion rate (TD) (hereinafter "TD (%)") is a sum of shrinkage rate and expansion rate measured by the expansion test method of JIS M 8801.

In addition, the softening point of Table 1 was measured by the softening point test method of JISK2531 (method similar to ASTM D36). In addition, Table 2 D ¹⁵⁰ ₁₅ in the coke strength was measured by the rotation strength test method (drum method) of JIS K 2151. The expansion pressure in Table 2 was measured by the following method. Into the movable wall type test coke oven having a furnace width of 400 mm, a furnace length of 1000 mm, and a furnace height of 1000 mm, a coal mixture obtained by adjusting the moisture to 3% was charged at a charging density of 0.85 t / m 3, and the coal mixture was 1250. It dried at 18 degreeC for 18 hours. The load acting on the movable wall in this distillate was continuously measured, and the measured maximum load was divided by the furnace wall area where coal contacted, and the expansion pressure was calculated | required.

As shown in Table 2, in the first comparative example, no caking additive was added to the raw coal. In this case, the coke strength DI ¹⁵⁰ ₁₅ (drum index DI ¹⁵⁰ ₁₅ ) of the manufactured coke was 84.0. Incidentally, the amount of increase in coke strength (DI increase amount ΔDI ¹⁵⁰ ₁₅ ) in the second to seventh comparative examples and the first to seventh examples is calculated based on the coke strength of the first comparative example. That is, the increase amount of coke strength is a difference with the coke strength of a 1st comparative example.

In the first comparative example, the inflation pressure was 10.0 kPa. If the expansion pressure is too high, there is a possibility that the furnace wall or the like to the coke oven is damaged, so that the suppression of the expansion pressure is desired.

In the second comparative example, the petroleum-based solid caking additive A1 (85 mass% of particles having a particle size of less than 3 mm) was added to the raw coal b. The addition rate of the petroleum-based solid caking additive A1 with respect to all the raw materials was 3 mass%. Compared with the first comparative example, the coke strength DI ¹⁵⁰ ₁₅ increased 0.9 and the expansion pressure decreased. In addition, solid caking additive A1 can be atomized by grinding | pulverization at a laboratory level. However, since the solid caking additive A1 is softened (viscosity decreases) by heat at the time of grinding | pulverization industrially, it cannot be atomized. In addition, the caking additive total addition rate totaled the addition rates of all caking additives (solid caking additive and liquid caking additive). Improvement of the coke strength effects (DI improvement ΔDI ¹⁵⁰ ₁₅ /% by mass), is the increase of the addition points settlement coke strength per 1% by mass. The improvement effect of this coke strength was computed by dividing the increase amount of coke strength by the caking additive total addition rate. In the 2nd comparative example, the improvement effect (DI improvement effect) of coke strength was 0.30 (0.9 / 3) / mass%.

In the third comparative example, only the coal caking additive B was added to the raw coal b. The addition rate of the coal-based liquid caking additive B with respect to all the raw materials was 3 mass%. Compared with the first and second comparative examples, the coke strength increased and the expansion pressure decreased. In addition, the DI improvement effect was larger than the 2nd comparative example. From the comparison between the second comparative example and the third comparative example, it can be seen that the liquid caking additive which easily penetrates the raw coal is effectively bonded between the raw coals.

In Comparative Examples 4-7, the solid caking additive A1 (the ratio of the particles having a particle diameter of less than 3 mm was 85% by mass) and the liquid caking additive B were added to the raw coal b. In addition, in the 4th comparative example, the addition rate of the solid caking additive A1 was 0.75 mass%, the addition rate of the liquid caking additive B was 2.25 mass%, and the caking additive total addition rate was 3 mass%. In the 5th comparative example, the addition rate of the solid caking additive A1 was 1.5 mass%, the addition rate of the liquid caking additive B was 1.5 mass%, and the caking additive total addition rate was 3 mass%. In the 6th comparative example, the addition rate of the solid caking additive A1 was 0.3 mass%, the addition rate of the liquid caking additive B was 2.7 mass%, and the caking additive total addition rate was 3 mass%. In the 7th comparative example, the addition rate of the solid caking additive A1 was 1 mass%, the addition rate of the liquid caking additive B was 3 mass%, and the caking additive total addition rate was 4 mass%.

In Examples 1 to 4, according to the first embodiment of the present invention described above, the mixed caking material obtained by dissolving the solid caking material A1 in the liquid caking material B was added to the raw coal b. In Example 1, the addition rate of the solid caking additive A1 was 0.75 mass%, the addition rate of the liquid caking additive B was 2.25 mass%, and the caking additive total addition rate was 3 mass%. In Example 2, the addition rate of the solid caking additive A1 was 1.5 mass%, the addition rate of the liquid caking additive B was 1.5 mass%, and the caking additive total addition rate was 3 mass%. In Example 3, the addition rate of the solid caking additive A1 was 0.3 mass%, the addition rate of the liquid caking additive B was 2.7 mass%, and the caking additive total addition rate was 3 mass%. In Example 4, the addition rate of the solid caking additive A1 was 1 mass%, the addition rate of the liquid caking additive B was 3 mass%, and the caking additive total addition rate was 4 mass%.

In Example 5, the mixed caking additive obtained by dissolving the solid caking additive A1 in the liquid caking additive C was added to the raw coal b according to the first embodiment of the present invention described above. In Example 5, the addition rate of the solid caking additive A1 was 1 mass%, the addition rate of the liquid caking additive B was 3 mass%, and the caking additive total addition rate was 4 mass%.

In the sixth example, the mixed caking additive obtained by dissolving the solid caking additive A2 in the liquid caking additive B was added to the raw coal b according to the first embodiment of the present invention described above. In Example 6, the addition rate of the solid caking additive A2 was 1 mass%, the addition rate of the liquid caking additive B was 3 mass%, and the total addition rate of the caking additive was 4 mass%. In Example 7, according to the first embodiment of the present invention described above, the mixed caking material obtained by dissolving the solid caking additive A3 in the liquid caking additive B was added to the raw coal b. In Example 7, the addition rate of the solid caking additive A3 was 1 mass%, the addition rate of the liquid caking additive B was 3 mass%, and the total addition rate of the caking additive was 4 mass%.

Here, in the fourth comparative example and the first example, the fifth comparative example and the second example, the sixth comparative example and the third example and the seventh comparative example and the fourth example, the solid caking additive A1 and the liquid dot The addition rate of the binder B is the same. In addition, in the seventh comparative example and the fifth to seventh examples, the addition rates of the solid caking additive and the liquid caking additive are the same, and the types of the solid caking additive or the liquid caking additive are different.

In the fourth to seventh comparative examples and the first to seventh examples, the coke strength increased and the expansion pressure decreased, as compared with the first and second comparative examples. In Table 3, the coke strength, the expansion pressure, the coke strength increase amount, and the DI improvement effect in the fourth to seventh comparative examples and the first to seventh examples shown in Table 2 are described in accordance with the addition amount of each caking additive. I am arranging.

The coke strength of the first to seventh examples was larger than the coke strength of the corresponding fourth to seventh comparative examples. In addition, the inflation pressure of the 1st-7th Example was small compared with the inflation pressure of the corresponding 4th-7th comparative example. In particular, in the fourth to seventh embodiments, the expansion pressure was further suppressed. The DI improvement effect of the 1st-7th Example was all 0.6 or more, and was large compared with the DI improvement effect of the 4th-7th comparative example. In addition, the DI improvement effect of the 1st-7th Example was 2 times or more of the DI improvement effect of the 2nd comparative example which added only solid caking additive A1.

Moreover, the coke strength of the 3rd comparative example which added only 3 mass% of liquid caking additives was 85.8, and expansion pressure was 7.0 kPa. However, in the fourth to seventh embodiments in which 1 mass% of the solid caking additive was dissolved in the 3 mass% liquid caking additive, the coke strength was greatly increased to 86.4 or more, and the expansion pressure could be greatly reduced to 6.1 kPa or less. . In the first to seventh embodiments, the handling of the mixed caking additive including the solid caking additive was as easy as the handling of the liquid caking additive. In addition, the caking characteristic of the solid caking additive was able to be utilized to the maximum.

In the manufacturing method of blast furnace coke, a solid caking additive can be used as a caking additive of the liquid added to a coke raw material coal, and the coke strength can be improved and a swelling pressure can be reduced.

1: coal (raw coal)
2: grinder
3: kneader
4: solid caking additive
5: sizing machine
6: coke oven
7: coke
8: liquid caking additive
11: solid caking additive
12: heating container
13: mixed caking additive
14: dry classifier
15: pulverized coal
16: granulated coal

Claims (8)

The liquid caking additive of the coal system is heated to a temperature at or above the liquefaction temperature at which the viscosity of the coal-based liquid caking additive becomes 100 cP, and at a temperature below the liquefaction temperature at which the viscosity of the petroleum-based solid caking additive becomes 100 cP,
Dissolving the petroleum-based solid binder in the liquid binder of the coal-based to prepare a mixed binder;
Raw coal is mixed with the mixed caking additive to prepare a mixed raw material,
A method for producing blast furnace coke, characterized in that the mixed raw material is carbonized. The said petroleum-based solid caking additive has a softening point of 180 degrees C or less, The manufacturing method of the blast furnace coke of Claim 1 characterized by the above-mentioned. The said petroleum-based solid caking additive is asphalt pitch, The manufacturing method of the blast furnace coke of Claim 1 characterized by the above-mentioned. The said coal-based liquid caking additive is coal tar, The manufacturing method of the blast furnace coke of Claim 1 characterized by the above-mentioned. The heating temperature of the said liquid caking additive of the said coal system is 150 degrees C or less, The manufacturing method of the blast furnace coke of Claim 1 characterized by the above-mentioned. The viscosity of the said mixed caking additive in the said temperature is 100 cP or less, The manufacturing method of the blast furnace coke of Claim 1 characterized by the above-mentioned. The method for producing blast furnace coke according to claim 1, wherein the raw coal is pulverized coal. The method for producing blast furnace coke according to claim 7, wherein the pulverized coal is obtained by pulverizing and classifying coal.

Images