Raw material manufacturing apparatus for blast furnace and raw material manufacturing method for blast furnace

Abstract

To provide a method and an apparatus for manufacturing a raw material for a blast furnace by which it is possible to enhance quality and productivity of the raw material for the blast furnace, such as ferro coke.SOLUTION: An apparatus for manufacturing a raw material for a blast furnace includes a pyrolysis furnace and a charging chute that is disposed above the pyrolysis furnace and supplies a carbon-containing material to the pyrolysis furnace. The pyrolysis furnace includes a gas ejection part that ejects gas toward a housing part surrounded by a wall part. The gas ejection part is located above a heat supply means disposed on the wall part of the pyrolysis furnace, and is disposed on the wall part below the charging chute.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an apparatus for manufacturing raw materials for a blast furnace used in a blast furnace such as formed coke, particularly ferrocoke, and a method for manufacturing raw materials for a blast furnace.

Background Art

[0002] In recent years, from the perspective of global warming, the steel industry has been required to reduce the amount of CO2 gas generated. For this reason, it has become an urgent task to reduce the use of fossil fuels. In the steel industry, hot metal is produced by reducing iron ore with carbon (coke produced by carbonizing coal in a coke oven) in a blast furnace. And, in order to reduce the coke unit, the development of a technology using ferrocoke as a raw material for a blast furnace has been carried out. Ferrocoke is a formed coke in which a certain amount of iron ore is mixed with coal, pelletized, and then subjected to carbonization treatment to disperse fine metallic iron particles in the coke, and the reactivity of the coke is enhanced by the catalytic action of the metallic iron.

[0003] As a carbonization method for ferrocoke, a method using a vertical carbonization furnace has been proposed. Patent Document 1 discloses a vertical carbonization furnace having a carbonization zone at the upper part and a cooling zone at the lower part. The method for manufacturing ferrocoke in a vertical carbonization furnace includes a charging step of charging a molded product composed of a carbon-containing substance and an iron-containing substance into the vertical carbonization furnace using a charging device, a carbonization step of blowing a heating gas into the carbonization zone and carbonizing the molded product to produce ferrocoke, a cooling step of cooling the ferrocoke by blowing a cooling gas into the cooling zone, a furnace gas discharging step of discharging the furnace gas from the discharge port at the top of the vertical carbonization furnace, and a ferrocoke discharging step of discharging the ferrocoke from the lower part of the cooling zone.

[0004] In the carbonization step, the molded product is heated by blowing a low-temperature gas from a low-temperature gas blowing port in the middle part of the carbonization zone and a high-temperature gas from a high-temperature gas blowing port in the lower part of the carbonization zone into the furnace. In the cooling step, the ferrocoke is cooled by blowing a cooling gas from a cooling gas blowing port in the lower part of the cooling zone.

[0005] Here, in order to increase the production amount of ferrocoke, it is necessary to increase the volume of the vertical retort furnace. Generally, the charged material is charged in an inclined direction using an inclined charging chute with the inclined direction as the charging direction. However, since the heating gas and the cooling gas are injected in the depth direction of the vertical retort furnace (parallel to the horizontal component of the charging direction of the charged material), it is necessary to keep the inner dimension in the depth direction below a certain level in order to allow the gas to penetrate to the central part of the furnace. Therefore, the vertical retort furnace is configured to have a longer inner dimension in the furnace width direction (the direction orthogonal to the depth direction in the cross section of the retort furnace) than in the depth direction, ensuring a large volume.

[0006] In addition, Patent Document 2 discloses a method of uniformly charging (conveying) materials by providing a dispersion guiding part having an inclined surface that slopes radially downward from the central part in the width direction of the conveying path toward the outlet side to disperse the materials radially.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] However, in a vertical retort furnace having a structure with a larger size in the furnace width direction than in the depth direction, in order to evenly disperse the carbon-containing material corresponding to the size in the furnace width direction, it is difficult to arrange a large number of charging chutes corresponding to all positions in the furnace width direction. On the other hand, the powder generated by the collision between the molded product and the wall surface of the charging chute or the collision between the molded products is likely to segregate, and tends to gather on the charging chute side at the bottom of the furnace inside the vertical retort furnace. This is because most of the powder in the charged material passes through the gaps between the molded products and settles during the process of passing through the charging chute, causing the charged material to separate into two layers, namely, a molded product layer (upper layer) and a powder layer (lower layer), before reaching the retort furnace. When 1 ton of molded products is charged, the thickness of the charged material when entering the retort furnace is at most about 150 mm. However, since the molded products are charged from a position higher than the powder existing below them, they are likely to fly to a position far from the charging port, while the powder in the lower layer falls near the charging port.

[0009] Also, at the bottom of the furnace inside the vertical retort furnace, the deposited molded products form a mountain-shaped slope according to the angle of repose. And the formed mountain-shaped slope has a greater inclination as it gets closer to the top. Therefore, even when the powder lands at a position far from the charging port, it is slightly pushed back toward the charging port side and comes to rest. Thus, the moving distance of the powder from when it lands until it comes to rest becomes larger. That is, the mountain-shaped slope formed by the molded products reduces the dispersion in the depth direction of the retort furnace and causes significant uneven distribution of the powder. Due to the segregation of the powder, the gas flow inside the furnace becomes non-uniform, causing problems such as poor carbonization of the molded products.

[0010] In addition, since the dispersion guiding part disclosed in Patent Document 2 does not affect the flying distance of the powder, even if the dispersion guiding part is installed, the powder segregation on the charging port side cannot be eliminated.

[0011] The present invention has been made in view of such circumstances, and an object thereof is to provide a raw material manufacturing apparatus for a blast furnace and a raw material manufacturing method for a blast furnace that improve the distribution of the charged material in the furnace of a vertical retort furnace, particularly the distribution of the powder contained in the charged material.

Means for Solving the Problems

[0012] To solve the above problems, the present invention has the following features.

[0013] [1] In a raw material manufacturing apparatus for a blast furnace having a retort furnace body and a charging chute provided above the retort furnace body and supplying a carbon-containing substance to the retort furnace body, the retort furnace body has a gas ejection part that ejects gas toward a housing part surrounded by a wall part, the gas ejection part is above a heat supply means provided on the wall part of the retort furnace body and is provided on the wall part below the charging chute, a raw material manufacturing apparatus for a blast furnace. [2] the gas ejection part is provided with a discharge port that discharges the gas at a position not in contact with the carbon-containing substance deposited on the retort furnace body, the discharge port, at least a part of which is located below the apex of the carbon-containing substance deposited on the retort furnace body, the raw material manufacturing apparatus for a blast furnace according to [1]. [3] the retort furnace body has a pair of wall parts arranged opposite to each other in the depth direction thereof, the gas ejection part ejects the gas in the depth direction, the raw material manufacturing apparatus for a blast furnace according to [1] or [2]. [4] the charging chute is provided on one of the pair of wall parts, the gas ejection part ejects the gas from the wall part on which the charging chute is provided in a direction in which the pair of wall parts face each other, the raw material manufacturing apparatus for a blast furnace according to [3]. [5] the gas ejection part ejects the gas at a flow rate of 15 to 20 m / s, the raw material manufacturing apparatus for a blast furnace according to any one of [1] to [4]. [6] the gas ejection part has a discharge port for discharging the gas, The height from the lower end of the discharge port of the gas ejection part to the apex of the charged material of the carbon-containing material supplied to the retort furnace and the distance between the pair of wall parts satisfy the following formula, The raw material manufacturing apparatus for blast furnaces according to any one of [3] to [5]. 0.07 ≦ d / W ≦ 0.15 d: Height from the lower end of the discharge port of the gas ejection part to the apex of the charged material W: Distance between the pair of wall parts [7] A method for manufacturing a raw material for a blast furnace, which manufactures a raw material for a blast furnace using the raw material manufacturing apparatus for a blast furnace according to any one of [1] to [6]. [8] A supply step of supplying the carbon-containing material to the retort furnace, A leveling step of discharging the gas from the gas ejection part, and has, The supply step is executed two or more times, The leveling step is executed between the execution of the supply step and the execution of the next supply step. The method for manufacturing a raw material for a blast furnace according to [7]. [Advantages of the Invention]

[0014] According to the present invention, it is possible to improve the distribution of the charged material in the retort furnace, particularly the distribution of the powder contained in the charged material. [Brief Description of the Drawings]

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0016] Hereinafter, taking the case of manufacturing ferrocoke, which is a kind of formed coke obtained by mixing a certain amount of iron ore with coal and forming it into lumps, as an example, the present invention will be described through embodiments of the present invention. Here, each drawing is schematic and may be different from the actual one. Further, the following embodiments illustrate apparatuses and methods for embodying the technical idea of the present invention, and do not specify the configuration to be the following. That is, various changes can be made to the technical idea of the present invention within the technical scope described in the claims.

[0017] Referring to FIG. 1, the configuration of a conventional vertical retort furnace 100 will be described. FIG. 1 shows a side schematic view of the vertical retort furnace 100. In the following description, the "charged material" is not limited to the "formed product containing a carbon-containing substance and an iron-containing substance" for manufacturing ferrocoke, and may also include a "formed product containing a carbon-containing substance". That is, any formed product containing at least a carbon-containing substance may be used. The "charged material" includes a "formed product" and "powder" attached to or separated from the "formed product". Further, the "blast furnace raw material" means "coke" containing ferrocoke.

[0018] The vertical retort furnace 100 has a charging chute 10, a charging gate 20, a diffusing section 30, and a retort furnace body 70. First, the charge containing the molded product containing the carbon-containing substance (coal) and the iron-containing substance (iron ore) is supplied to the charging chute 10 provided above the retort furnace body. The charge is once accumulated inside the charging chute 10 (in the middle of the charging chute 10) by closing the charging gate 20 (refer to the dashed line in the figure). The charge passes through the inside of the charging chute 10 toward the retort furnace body 70 when the charging gate 20 is opened (shown by the solid line in the figure). The charge is dispersed so as to spread inside the charging chute 10 by passing through the diffusing section 30 of the charging chute 10. After passing through the inside of the charging chute 10, the charge accumulates inside the retort furnace body 70. The charge forms a mountain shape according to the angle of repose inside the retort furnace body 70.

[0019] Here, as described above, the charge charged into the retort furnace body 70 is separated into two layers, a molded product layer (upper layer) and a powder layer (lower layer), inside the charging chute 10 before reaching the retort furnace body 70. Therefore, as shown in FIG. 1, the charge charged into the retort furnace body 70 falls inside the retort furnace body 70 while separating into the molded product layer 40 and the powder layer 50. For this reason, the charge 60 accumulated inside the retort furnace body 70 is in a state where the molded product and the powder are unevenly distributed. Due to this uneven distribution, in the conventional vertical retort furnace 100, the gas flow inside the retort furnace body 70 becomes non-uniform, and problems such as poor carbonization of the molded product occur.

[0020] <Configuration of gas ejection part etc.> Next, with reference to FIG. 2, the configuration of the vertical retort furnace 11 which is an embodiment of the present invention will be described. FIG. 2 is a side schematic view of the vertical retort furnace 11 as a raw material manufacturing apparatus 12 for a blast furnace. The vertical retort furnace 11 shown in FIG. 2 further includes a gas ejection part 80 with respect to the vertical retort furnace 100 shown in FIG. 1.

[0021] Fig. 2(a) shows the state where a prior charge is charged into the vertical retort furnace 11. Fig. 2(b) shows the operation mode of the gas ejection part 80 of the vertical retort furnace 11. Fig. 2(c) shows the mode in which a subsequent charge is charged onto the prior charge from which gas has been ejected by the gas ejection part 80.

[0022] As shown in Fig. 2, the retort furnace main body 7 has a pair of wall parts 7a facing each other in the depth direction S. The gas ejection part 80 is provided on one of the wall parts 7a where the charging chute 1 of the retort furnace main body 7 is provided. By ejecting gas toward the charge 6 (toward the depth direction S), the gas ejection part 80 can level the charge 6 formed in a mountain shape. And by leveling the charge 6 formed in a mountain shape, the "formed product" and "powder" of the charge 6 are mixed in the vertical direction and the horizontal direction. Thereby, the distribution of the charge 6 in the furnace of the vertical retort furnace 11, particularly the distribution of the powder contained in the charge 6, can be improved.

[0023] The tuyere 14 as a heat supply means is provided on the wall part 7a. The gas ejection part 80 is provided above the tuyere 14 and below the charging chute 1.

[0024] The gas ejection part 80 has a pipe 81 serving as a gas flow path, and a discharge port 82 which is the tip of the pipe 81 and is formed by opening to the wall part 7a. The discharge port 82 is provided at a position not in contact with the charge 6 deposited on the retort furnace main body 7. At least a part of the discharge port 82 is located below the apex of the charge 6 deposited on the retort furnace main body 7.

[0025] The gas ejected from the gas ejection part 80 is not particularly limited, but those having poor reactivity with the charge 6 and the raw material for blast furnace obtained by carbonizing the charge 6 in the retort furnace are preferred, and examples thereof include inert gases such as N2, CO2, and Ar.

[0026] The pipe 81 preferably has corrosion resistance against the gas discharged to the retort furnace main body 7. A gas supply device (not shown) is connected to the proximal end of the pipe 81. As the gas supply device, gas supply facilities such as a candle can be used.

[0027] The discharge port 82 is formed so as to be able to supply a predetermined wind pressure to the charged material 6. The wind pressure of the gas discharged from the discharge port 82 is preferably at least a wind pressure capable of moving a powder having an average particle size of 20 mm or less. The average particle size of the powder can be measured, for example, by sieving with a mesh.

[0028] In consideration of the above, the gas ejection unit 80 preferably discharges gas from the discharge port 82 at a flow velocity of 15 to 20 m / s. The flow velocity and flow rate of the gas flowing through the pipe 81 can be adjusted using a known pressure regulator such as a solenoid valve. Thus, the gas ejection unit 80 preferably has a gas flow velocity adjusting means for adjusting the flow velocity of the gas discharged from the discharge port 82.

[0029] If the flow velocity of the gas discharged from the discharge port 82 is less than 15 m / s, the desired charged material 6 cannot be sufficiently moved, and it is difficult to level the mountain-shaped charged material 6. Further, if the flow velocity of the gas discharged from the discharge port 82 exceeds 20 m / s, the charged material 6 blown away by the gas may vigorously contact the wall portion 7a, and a part of it may become powder.

[0030] The gas ejection unit 80 is preferably provided so as to satisfy the following formula (1) when the height from the lower end of the discharge port 82 to the apex of the charged material is d and the distance between the pair of wall portions 7a is W. By providing the gas ejection unit 80 at a position satisfying the relationship of the following formula (1), the mountain-shaped charged material 6 can be efficiently leveled (collapsed). 0.07 ≦ d / W ≦ 0.15 (1)

[0031] When d / W is less than 0.07, the contact between the gas discharged from the gas ejection unit 80 and the chevron-shaped charged material decreases. For this reason, the amount of the charged material 6 moved by the gas discharged from the gas ejection unit 80 decreases, and the chevron-shaped charged material 6 cannot be leveled sufficiently.

[0032] When d / W exceeds 0.15, the amount of the charged material 6 present in the gas progress direction increases, making it difficult to move the charged material 6. For this reason, the time required to level the chevron-shaped charged material 6 becomes longer. If the amount of the gas discharged from the gas ejection unit 80 is increased so that the time does not become longer, the operation cost becomes high, which is not preferable.

[0033] <Method for manufacturing raw material for blast furnace> Next, a method for manufacturing a raw material for a blast furnace that levels the chevron-shaped charged material 6 deposited inside the dry distillation furnace body 7 by means of the vertical dry distillation furnace 11 having the gas ejection unit 80 will be described.

[0034] The method for manufacturing a raw material for a blast furnace includes a supply step of supplying a carbon-containing substance to the dry distillation furnace body 7 and a leveling step of discharging gas from the gas ejection unit 80. The supply step is executed two or more times, and the leveling step is executed after one supply step is executed and before the next supply step is executed.

[0035] FIG. 3 shows the operation mode of the gas ejection unit 80 in the leveling step. As shown in FIG. 3, in the leveling step, the gas ejection unit 80 ejects gas 83 against the charged material 6 deposited inside the dry distillation furnace body 7. Thereby, the chevron-shaped charged material 6 can be leveled (collapsed) efficiently.

[0036] Here, as described above, the charge (hereinafter also referred to as "preceding charge") that is first charged into the vertical retort furnace 11 is formed in a mountain shape and deposited inside the retort furnace body 7. Then, the charge (hereinafter also referred to as "subsequent charge") that is subsequently charged into the vertical retort furnace 11 is separated into two layers, namely, the formed product layer 4 and the powder layer 5, when it falls from the charging chute 1 toward the inside of the retort furnace body 7. And when the powder layer 5 of the subsequent charge lands near the top of the mountain shape formed by the preceding charge, the moving distance until it moves along the slope of the mountain shape and comes to rest becomes large. For this reason, the moving distance of the powder contained in the powder layer 5 of the subsequent charge becomes large, and the uneven distribution of the powder in the charge 6 deposited inside the retort furnace body 7 becomes prominent.

[0037] On the other hand, in the present embodiment, when the preceding charge previously charged into the vertical retort furnace 11 is deposited in a mountain shape inside the retort furnace body 7, gas is discharged from the gas ejection part 80 to the preceding charge to level the charge 6.

[0038] FIG. 4 shows the mode of the supply step after the leveling step is executed. As shown in FIG. 4, after the leveling step is executed, the subsequent charge is charged into the vertical retort furnace 11. Thereby, when the subsequent charge falls toward the inside of the retort furnace body 7, since the preceding charge is not formed in a mountain shape, uneven distribution of the powder contained in the subsequent charge due to moving along the slope does not occur, and powder segregation can be alleviated.

[0039] As described above, according to the present invention, by providing the gas ejection part 80 on the wall part 7a of the retort furnace body 7, the distribution of the charge 6 in the furnace of the vertical retort furnace 11, particularly the distribution of the powder contained in the charge 6, can be improved.

Example

[0040] (Test Example 1: Gas Discharge Direction Test) The influence of the gas ejection direction on the leveling of the unevenness of the charged material was investigated. That is, for a plurality of examples in which the gas ejection direction was changed, in a test system modeled after a retort furnace, the influence was evaluated using the standard deviation of the height of the charged material and the maximum powder ratio.

[0041] (Raw material manufacturing equipment for blast furnace) A test device that simulated a ferrocoke manufacturing device was used as the test system. A charging chute having the same shape as that installed in the actual machine was used, and a recovery box having the same shape as a retort furnace modeled after a retort furnace was installed on the outlet side of the charging chute.

[0042] A gas ejection part was provided in the recovery box, and the operation mode thereof was changed. Specifically, when no gas was ejected from the gas ejection part (none), a gas ejection part was provided on one of a pair of wall parts provided in a direction orthogonal to the depth direction of the recovery box, and gas was ejected toward the other wall part (B1), a gas ejection part was provided on the other of a pair of wall parts provided in a direction orthogonal to the depth direction of the recovery box, and gas was ejected toward one wall part (B2), a gas ejection part was provided on one of a pair of wall parts provided in the depth direction of the recovery box, and gas was ejected toward the other wall part (A1), and a gas ejection part was provided on the other of a pair of wall parts provided in the depth direction of the recovery box, and gas was ejected toward one wall part (A2). Tests were conducted for these examples.

[0043] In addition, d / W: (height from the lower end of the discharge port 82 to the apex of the charged material) / (distance between wall parts in the gas ejection direction of the gas ejection part 80) was set to 0.10. Further, the flow velocity of the gas ejected from the gas ejection part was set to 20 m / s. Nitrogen was used as the gas ejected from the gas ejection part.

[0044] The charged material consisted of 95% by mass of the molded product and 5% by mass of the powder. Also, the amount of the charged material supplied to the recovery box in one supply operation was set to 25 kg. In this example, the charged material with a diameter of 20 mm or more was defined as the "molded product", and the charged material with a diameter of less than 20 mm was defined as the "powder". For measuring the particle size, a square sieve with a mesh opening of 20 mm was used. What remained on the sieve was regarded as the granular material, and what fell through the sieve was regarded as the powder.

[0045] (Measurement and Evaluation) After discharging gas from the gas ejection part to level the unevenness of the charged material, the height of each charged material was measured at five points (in the depth direction) of the charged material, and the standard deviation of the height was calculated from the measurement results.

[0046] After that, the second supply operation of the charged material was performed. Further, at the above five locations, sampling was carried out to investigate the powder ratio. The powder ratio was defined as the weight ratio of the sample (powder) that fell through a square sieve with a mesh opening of 20 mm. Also, the maximum powder ratio was the maximum value of the powder ratios obtained by comparing the powder ratios at these five points. The results are shown in Figure 5.

[0047] As shown in Figure 5, regardless of whether the gas was discharged in the directions of B1, B2, A1, or A2, better results were obtained for the "standard deviation of height" and the "maximum powder ratio" than when no gas was discharged from the gas ejection part (none).

[0048] Also, regardless of whether the gas ejection part was operated in the directions of A1 or A2, better results were obtained for the "standard deviation of height" and the "maximum powder ratio" than when the gas ejection part was operated in the directions of B1 or B2.

[0049] Furthermore, when the gas ejection part was operated in the direction of A2, better results were obtained for the "maximum powder ratio" than when the gas ejection part was operated in the direction of A1.

[0050] From the above results, it was confirmed that, particularly by setting the gas ejection direction to the depth direction of the apparatus (A1, A2), the chevron-shaped molded product (charged material) can be effectively leveled. As a result, it can be seen that the deposition of the powder contained in the charged material supplied for the second time at a biased position can be suppressed.

[0051] In addition, particularly by ejecting the gas from the wall portion provided with the charging chute toward the opposing wall portion (A2), while leveling the chevron-shaped molded product (charged material), the powder staying in the vicinity of the charging chute can be pushed out in that direction. As a result, the deposition of the powder contained in the charged material at a biased position can be suppressed.

[0052] (Test Example 2: Gas Flow Velocity Test) Next, the results of an investigation into the influence of the gas flow velocity on the leveling of the unevenness of the charged material will be described. In the gas flow velocity test, for a plurality of examples with different gas flow velocities, in a test system modeled after a retort furnace, the influence was evaluated using the standard deviation of the height of the charged material and the maximum powder ratio. In this test example, the same apparatus as in Test Example 1 was used. Also, in this test example, the standard deviation of the height of the charged material and the maximum powder ratio were measured in the same manner as in Test Example 1. The results are shown in FIG. 6.

[0053] Note that d / W: (height from the lower end of the discharge port 82 to the apex of the charged material) / (distance between the wall portions in the gas ejection direction of the gas ejection portion 80) was set to 0.10. Also, a gas ejection portion was provided on the wall portion where the charging chute is provided among the pair of wall portions, and the gas was ejected toward the other wall portion.

[0054] As shown in FIG. 6, when the gas flow velocity was less than 15 m / s, better results were obtained than when no gas was ejected from the gas ejection portion (gas flow velocity: 0). On the other hand, when the gas flow velocity was 15 m / s or more, better results were obtained for the standard deviation and the maximum powder ratio than when no gas was ejected from the gas ejection portion (gas flow velocity: 0).

[0055] Furthermore, when the gas flow rate exceeded 20 m / s, the maximum powder ratio increased. That is, in this flow rate range, it was confirmed that the charged material blown away by the gas vigorously contacted the wall and shattered, increasing the powder.

[0056] From the above results, it was confirmed that the flow rate of the gas discharged from the gas ejection part is preferably 15 - 20 m / s.

[0057] (Test Example 3: Gas Injection Position Test) Next, the results of investigating the influence of the arrangement relationship of the gas ejection part on the leveling of the unevenness of the charged material will be described. In the gas injection position test, for a plurality of examples in which the height d from the lower end of the discharge port to the apex of the charged material was changed, the standard deviation of the height of the charged material and the maximum powder ratio in the test system modeled after the retort furnace were confirmed. In this test example, the same apparatus as in Test Example 1 was used. Also, in this test example, the standard deviation of the height of the charged material and the maximum powder ratio were measured in the same manner as in Test Example 1. Furthermore, the gas discharge by the gas ejection part was made horizontal.

[0058] Note that the flow rate of the gas discharged from the gas ejection part was 20 m / s. Also, the gas ejection part was provided on the side where the charging chute was provided among the pair of wall parts, and the gas was discharged toward the other wall part.

[0059] The results are shown in Fig. 7. As shown in Fig. 7, when d / W was less than 0.07, the standard deviation of the height exceeded 75 mm in all cases. That is, when d / W was less than 0.07, since the lower end of the discharge port was located at approximately the same height as the apex of the charged material, it was found that it was difficult to sufficiently level the mountain-shaped charged material.

[0060] Also, when d / W is 0.07 or more, good results were obtained for the standard deviation of height and the maximum powder ratio. Here, in the example where d / W is 0.07 or more, the time required to level the mountain-shaped charge is as follows. When d / W is 0.10, it was 11 seconds. When d / W is 0.15, it was 12 seconds. When d / W is 0.18, it was 16 seconds. When d / W is 0.20, it was 21 seconds. Thus, it was found that when d / W exceeds 0.15, the time required to level the mountain-shaped charge tends to become longer.

[0061] From the above results, it was confirmed that the ratio of the height d from the lower end of the discharge port to the apex of the mountain-shaped charge to the distance W between the wall portions in the gas discharge direction of the gas ejection portion is preferably in the range of 0.07 ≤ d / W ≤ 0.15.

Explanation of Signs

[0062] 1 Charging chute 4 Molded product layer 5 Powder layer 6 Charge 7 Carbonization furnace body 7a Wall portion 10 Charging chute 11 Vertical carbonization furnace 12 Blast furnace raw material manufacturing apparatus 13 Accommodation portion 80 Gas ejection portion 82 Discharge port 83 Gas

Claims

1. In a raw material manufacturing apparatus for a blast furnace, comprising a retort furnace body, and a charging chute provided above the retort furnace body and configured to supply a carbon-containing substance to the retort furnace body, the retort furnace body has a gas ejection part that ejects gas toward an accommodation part surrounded by a wall part, the gas ejection part is provided above a heat supply means provided on the wall part of the retort furnace body and is provided on the wall part below the charging chute, the gas ejection part is provided with a discharge port that discharges the gas at a position not in contact with the carbon-containing substance deposited in the retort furnace body, the discharge port is, at least in part, located below the apex of the carbon-containing substance deposited in the retort furnace body, a raw material manufacturing apparatus for a blast furnace.

2. The retort furnace body has a pair of wall parts arranged opposite to each other in the depth direction thereof, the gas ejection part ejects the gas in the depth direction, a raw material manufacturing apparatus for a blast furnace according to Claim 1.

3. The charging chute is provided on one of the pair of wall parts, the gas ejection part ejects the gas in the direction in which the pair of wall parts face each other from the one wall part on which the charging chute is provided, a raw material manufacturing apparatus for a blast furnace according to Claim 2.

4. The gas ejection part discharges the gas at a flow rate of 15 to 20 m / s, a raw material manufacturing apparatus for a blast furnace according to Claim 1.

5. The gas ejection part discharges the gas at a flow rate of 15 to 20 m / s, a raw material manufacturing apparatus for a blast furnace according to Claim 2.

6. The gas ejection part discharges the gas at a flow rate of 15 to 20 m / s, a raw material manufacturing apparatus for a blast furnace according to Claim 3.

7. The gas ejection part has a discharge port for discharging the gas, a raw material manufacturing apparatus for a blast furnace according to Claim 2, wherein the distance between the pair of wall parts and the height from the lower end of the discharge port of the gas ejection part to the apex of the charge of the carbon-containing substance supplied to the retort furnace satisfy the following formula. 0.07 ≤ d / W ≤ 0.15 d: The height from the lower end of the discharge port of the gas ejection part to the apex of the charge W: The distance between the pair of wall parts

8. The gas ejection part has a discharge port for discharging the gas, a raw material manufacturing apparatus for a blast furnace according to Claim 3, wherein the distance between the pair of wall parts and the height from the lower end of the discharge port of the gas ejection part to the apex of the charge of the carbon-containing substance supplied to the retort furnace satisfy the following formula. 0.07 ≤ d / W ≤ 0.15 d: Height from the lower end of the gas ejection port of the gas ejection part to the apex of the charged material W: Distance between a pair of wall parts

9. The gas ejection part has a gas ejection port for ejecting the gas, The height from the lower end of the gas ejection port of the gas ejection part to the apex of the charged material of the carbon-containing material supplied to the retort furnace and the distance between a pair of wall parts arranged to face each other in the depth direction of the retort furnace main body satisfy the following formula. The raw material manufacturing apparatus for blast furnace according to claim 4. 0.07 ≤ d / W ≤ 0.15 d: Height from the lower end of the gas ejection port of the gas ejection part to the apex of the charged material W: Distance between a pair of wall parts

10. The gas ejection part has a gas ejection port for ejecting the gas, The height from the lower end of the gas ejection port of the gas ejection part to the apex of the charged material of the carbon-containing material supplied to the retort furnace and the distance between a pair of wall parts satisfy the following formula. The raw material manufacturing apparatus for blast furnace according to claim 5. 0.07 ≤ d / W ≤ 0.15 d: Height from the lower end of the gas ejection port of the gas ejection part to the apex of the charged material W: Distance between a pair of wall parts

11. The gas ejection part has a gas ejection port for ejecting the gas, The height from the lower end of the gas ejection port of the gas ejection part to the apex of the charged material of the carbon-containing material supplied to the retort furnace and the distance between a pair of wall parts satisfy the following formula. The raw material manufacturing apparatus for blast furnace according to claim 6. 0.07 ≤ d / W ≤ 0.15 d: Height from the lower end of the gas ejection port of the gas ejection part to the apex of the charged material W: Distance between a pair of wall parts

12. A method for manufacturing a raw material for a blast furnace, which manufactures a raw material for a blast furnace using the raw material manufacturing apparatus for a blast furnace according to claim 1.

13. A supply step of supplying the carbon-containing material to the retort furnace, A leveling step of ejecting the gas from the gas ejection part, and having, The supply step is executed two or more times, The leveling step is executed between when the supply step is executed and when the next supply step is executed. The method for manufacturing a raw material for a blast furnace according to claim 12.

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