Granulation device, method for producing granulated sintered raw material, and method for producing sintered ore

Abstract

Provided are: a granulation device capable of efficiently heating a sintering raw material by blowing steam into the sintering raw material; a method for producing a granulation sintering raw material; and a method for producing a sintered ore using the method for producing a granulation sintering raw material.　This granulation device granulates a sintering raw material including an iron-containing material, a CaO-containing raw material, and a coagulation material. The granulation device has: a cylindrical drum that rotates around the horizontal direction as a rotation axis and is provided with an inlet through which the sintering raw material is put in, and a discharge port through which the granulated sintering raw material is discharged; a steam pipe provided inside the drum and provided only in an anterior half portion between the inlet and the intermediate position between the inlet and the discharge port; and multiple nozzles which are connected to the steam pipe and from which steam is ejected toward a deposition surface of the sintering raw material, wherein the multiple nozzles are provided 500 mm or more apart from the deposition surface of the sintering raw material.

Description

[Technical field]

[0001] The present invention relates to a granulating device for granulating a sintering raw material, a method for producing a granulated sintering raw material, and a method for producing sintered ore.

[0002] Sintered ore, which is a raw material for blast furnaces, is generally produced by using iron-containing raw materials such as iron ore powder, recovered powder in steelworks, and sintered ore undersize powder, CaO-containing raw materials such as limestone and dolomite, and carbonaceous materials (solid fuel) such as coke powder and anthracite as sintering raw materials, using a Dwight Lloyd sintering machine (hereinafter, sometimes referred to as "sintering machine"), which is an endless moving sintering machine. The sintering raw materials are charged into the endless moving pallet of the sintering machine to form a charging layer. The thickness (height) of the charging layer is about 400 to 800 mm. Then, the carbonaceous materials on the surface of the charging layer are ignited by an ignition furnace installed above the charging layer. The carbonaceous materials in the charging layer are sequentially burned by sucking air downward through a wind box arranged under the pallet. This combustion progresses gradually downward and forward as the pallet moves. The sintering raw materials are burned and melted by the combustion heat generated at this time, and a sintered cake is produced. The resulting sintered cake is then crushed in the ore discharge section, cooled in a cooler, and sized to produce sintered ore.

[0003] In the production of sintered ore using the above-mentioned sintering machine, a technique is known in which the ratio of the wet zone in the charging bed is reduced by preheating and drying the sintering raw material, thereby improving the permeability of the charging bed and improving the productivity of sintered ore. For example, Patent Document 1 discloses a method for producing granulated sintered raw material in which steam such as water vapor is injected during granulation of the sintering raw material to heat the sintering raw material. According to Patent Document 1, the sintering raw material is preheated and dried by granulating the sintering raw material while injecting water vapor, which improves the permeability of the charging bed and improves the productivity of sintered ore. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2019 / 167888 Summary of the Invention [Problem to be solved by the invention]

[0005] In the method disclosed in Patent Document 1, the sintering raw material is granulated while injecting steam, so that steam to be injected into the sintering raw material must be prepared separately. This poses a problem that the cost of preparing steam increases the cost of producing sintered ore. On the other hand, if the sintering raw material can be efficiently heated using steam, the amount of steam used can be reduced, and the increase in the cost of producing sintered ore can be suppressed. The present invention has been made in consideration of such problems in the prior art, and its purpose is to provide a granulation device that can efficiently heat the sintering raw material by injecting steam into the sintering raw material, a method for producing granulated sintered raw material, and a method for producing sintered ore using the method for producing granulated sintered raw material. [Means for solving the problem]

[0006] The means for solving the above problems are as follows. [1] A granulation device for granulating a sintering raw material containing an iron-containing raw material, a CaO-containing raw material, and a coagulant, comprising: a cylindrical drum having an inlet through which the sintering raw material is fed and an outlet through which the granulated sintering raw material is discharged, the drum rotating about a horizontal axis of rotation; a steam pipe provided within the drum only in the front half between the inlet and a midpoint between the inlet and the outlet; and a plurality of nozzles connected to the steam pipe and spraying steam onto the deposition surface of the sintering raw material, the plurality of nozzles being provided at a distance of 500 mm or more from the deposition surface of the sintering raw material. [2] The granulation apparatus described in [1], wherein the steam ejection direction of more than half of the plurality of nozzles is tilted toward the exhaust port, and the steam ejection direction of the remaining nozzles is set so as to eject steam perpendicular to the deposition surface of the sintering raw material. [3] The granulation apparatus described in [1] or [2], wherein the steam ejection direction of the multiple nozzles is tilted so that the nozzles face more toward the outlet as they approach the outlet. [4] A method for producing granulated sintered raw materials, which uses a granulating device to granulate sintered raw materials containing an iron-containing raw material, a CaO-containing raw material, and a coagulant, said granulating device having a cylindrical drum which is provided with an inlet through which the sintered raw materials are fed and an outlet through which the granulated sintered raw materials are discharged, and which rotates about a horizontal axis of rotation, and in which steam is blown into the sintered raw materials in the drum from a position 500 mm or more away from the deposition surface of the sintered raw materials in the first half of the drum between the inlet and a midpoint between the inlet and the outlet, to produce granulated sintered raw materials at a temperature 10°C or more higher than that of granulated sintered raw materials granulated without blowing in the steam. [5] The method for producing a granulated sintered raw material according to [4], wherein more than half of the total amount of steam injected into the sintered raw material is injected at an angle so that the direction of the steam injection faces the exhaust port side. [6] A method for producing sintered ore, comprising sintering in a sintering machine granulated raw material granulated by the method for producing granulated sintered raw material according to [4] or [5] to produce sintered ore. Effect of the Invention

[0007] By using the granulating device according to the present invention, the raw sinter material can be efficiently heated by injecting steam, thereby reducing the steam consumption rate used during granulation. By using this heated granulated raw sinter material, the permeability of the charging bed is improved and the productivity of sintered ore is improved. Therefore, by using the granulating device according to the present invention, the productivity of sintered ore can be improved and the manufacturing cost of sintered ore can be suppressed. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing an example of a sintered ore production facility 10 having a drum mixer 32 which is a granulating device according to this embodiment. [Diagram 2] FIG. 2 is a graph showing the relationship between the temperature of the sintering raw material at the outlet of the drum mixer and the permeability index JPU of the sintering bed. [Diagram 3] FIG. 3 is a graph showing the relationship between the temperature of the sintering raw material at the outlet of the drum mixer and the permeability index JPU of the sintering bed. [Figure 4]FIG. 4 is a schematic diagram illustrating the configuration of a drum mixer. [Diagram 5] FIG. 5 is a cross-sectional view of a drum mixer showing the location of multiple nozzles. [Figure 6] FIG. 6 is a graph showing the results of the steam injection experiment. [Figure 7] FIG. 7 is a schematic diagram showing a steam pipe. [Figure 8] FIG. 8 is a graph showing the results of the steam injection experiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The present invention will be described below through embodiments of the invention. Fig. 1 is a schematic diagram showing an example of a sintered ore production facility 10 having a drum mixer 32, which is a granulation device according to this embodiment. Iron-containing raw materials 12 stored in a yard 11 are transported to a blending tank 22 by a transport conveyor 14. The iron-containing raw materials 12 include various brands of iron ore and dust generated in a steelworks.

[0010] The raw material supply section 20 includes a plurality of blending tanks 22, 24, 25, 26, and 28. The blending tank 22 stores the iron-containing raw material 12. The blending tank 24 stores the CaO-containing raw material 16 containing limestone and quicklime, and the blending tank 25 stores the MgO-containing raw material 17 containing dolomite and refined nickel slag. The blending tank 26 stores the coke powder and anthracite aggregate 18 crushed to a particle size of 1 mm or less using a rod mill. The blending tank 28 stores the return ore (sintered ore undersieve powder) having a particle size of 5 mm or less that is undersieved from the sintered ore. A predetermined amount of each raw material is cut out from the blending tanks 22 to 28 of the raw material supply section 20, and these are blended to form the sintered raw material. The sintered raw material is transported to the drum mixer 32 by the transport conveyor 30. The MgO-containing raw material 17 is an optional blended raw material, and may or may not be blended with the sintered raw material.

[0011] The drum mixer 32 is a granulation device that granulates the sintering raw material while spraying steam onto it. The drum mixer 32 has a cylindrical drum 33 that rotates around a horizontal axis, a steam pipe 36, and a number of nozzles 37 that are connected to the steam pipe 36 and spray steam 38 onto the pile surface of the sintering raw material. Note that steam is an example of steam.

[0012] The cylindrical drum 33 is provided with an inlet 34 at one end face of the drum 33 through which the sintering raw material is introduced, and an outlet 35 at the other end face of the drum 33 through which the granulated sintering raw material (hereinafter referred to as pseudo particles) is discharged. The steam pipe 36 is provided in the drum 33 in a region that is the first half between the inlet 34 and the intermediate position between the inlet 34 and the outlet 35. The multiple nozzles 37 are provided at positions 500 mm or more away from the piled surface of the sintering raw material in the vertical direction, and blow steam from these positions toward the piled surface of the sintering raw material.

[0013] In this way, the pseudo-particles are produced by granulating the sintering raw material while blowing in water vapor, and the pseudo-particles are granulated to pseudo-particles with an average particle size of about 3.0 mm at a temperature 10° C. higher than that of pseudo-particles granulated without blowing in water vapor. The pseudo-particles are transported to the sintering machine 40 by a transport conveyor 39. In this embodiment, the average particle size of the pseudo-particles is an arithmetic mean particle size, which is defined as Σ(Vi×di) (where Vi is the abundance ratio of particles in the i-th particle size range, and di is the representative particle size of the i-th particle size range). The drum mixer 32 is an example of a granulating device that granulates the sintering raw material.

[0014] The sintering machine 40 is, for example, a downward suction type Dwight Lloyd type sintering machine. The sintering machine 40 has a sintering material supply device 42, an endless movable pallet cart 44, an ignition furnace 46, and a wind box 48. The sintering material is charged from the sintering material supply device 42 to the pallet cart 44, and a charging layer of the sintering material is formed. The charging layer is ignited by the ignition furnace 46. By sucking air through the wind box 48, the coagulant 18 is combusted in the charging layer, and the combustion and melting zone in the charging layer is moved downward in the charging layer. As a result, the charging layer is sintered to form a sintered cake. In this embodiment, a gas fuel supply device 47 may be provided. The gaseous fuel supplied from the gaseous fuel supply device 47 is any combustible gas selected from blast furnace gas, coke oven gas, blast furnace / coke oven mixed gas, converter gas, city gas, natural gas, methane gas, ethane gas, propane gas, shale gas, and mixed gases thereof.

[0015] The sintered cake is crushed by a crusher 50 to produce sintered ore. The sintered ore crushed by the crusher 50 is cooled by a cooler 52. The sintered ore cooled by the cooler 52 is sieved by a sieving device 54 having a plurality of sieves, and is sieved into a finished sintered ore 56 having a particle size of more than 5 mm and a return ore 58 having a particle size of 5 mm or less. The finished sintered ore 56 is used as a blast furnace raw material. Meanwhile, the return ore 58 is transported by a transport conveyor 60 to the blending tank 28 of the raw material supply section 20. In this embodiment, the particle size of the finished sintered ore 56 and the particle size of the return ore 58 refer to the particle size sieved by a sieve. For example, a particle size of more than 5 mm means a particle size sieved onto a sieve with a mesh size of 5 mm, and a particle size of 5 mm or less means a particle size sieved onto a sieve with a mesh size of 5 mm. The particle size values ​​of the product sinter 56 and the return ore 58 are merely examples and are not limited to these values.

[0016] In this way, in the production of sintered ore using the sinter ore production equipment 10, steam is blown into the sintering raw material in the drum mixer 32 to granulate and heat the sintering raw material. This improves the permeability of the sintering raw material charging bed, thereby increasing the productivity of the sintering raw material. FIG. 2 is a graph showing the relationship between the temperature of the pseudo-particles at the outlet of the drum mixer and the permeability index JPU of the charging bed. The horizontal axis of FIG. 2 is the temperature (°C) of the pseudo-particles discharged from the drum mixer 32. The temperature of the pseudo-particles is the average temperature of the pseudo-particles discharged from the drum mixer 32.

[0017] The temperature of the sintering raw material before being fed into the drum mixer 32 is 35.0°C. The sintering raw material includes a CaO-containing raw material. CaO reacts with water to form Ca(OH). 2 Since heat is generated when steam is generated, the temperature of the sintering raw material rises from 35.0°C to approximately 42.5°C even without blowing in steam. The plot at 42.5°C on the horizontal axis of Figure 2 is an example of granulation in which the sintering raw material was granulated without blowing in steam into the sintering raw material, and the other plots are examples of granulation in which steam was blown into the sintering raw material and the sintering raw material was heated.

[0018] The vertical axis of Figure 2 is the permeability index JPU of the sintering bed. JPU is the permeability index measured by cold sucking air downward through the sintering bed formed by charging pseudo-particles into a pallet. The permeability index JPU is calculated using the following formula (1).

[0019] JPU = V / [S × (ΔP / h) 0.6 ]···(1) In the above formula (1), V is the air volume (m 3 / min, and S is the effective area of ​​the sintering machine (m 2 ), h is the bed height (mm), ΔP is the pressure loss (mmH 2 O).

[0020] When the permeability of the sintering bed is high, the permeability index JPU becomes large, and when the permeability is low, the permeability index JPU becomes small. As shown in Figure 2, the permeability of the sintering bed was improved by injecting steam into the sintering raw material and raising the temperature of the pseudo-particles to above 42.5°C. In addition, the permeability of the sintering bed formed by the pseudo-particles at 56.0°C, which is 10°C higher than 42.5°C, was significantly higher than that of the pseudo-particles at 47.0°C. From this result, it is preferable to granulate the sintering raw material by injecting steam into the pseudo-particles at a temperature 10°C higher than that of the pseudo-particles granulated without injecting steam, and this leads to the pseudo-particles that form a sintering bed with high permeability.

[0021] FIG. 3 is a graph showing the relationship between the temperature of the pseudo-particles at the outlet of the drum mixer and the productivity of sintered ore. The horizontal axis of FIG. 3 is the temperature (°C) of the pseudo-particles discharged from the drum mixer 32. The vertical axis of FIG. 3 is the productivity of sintered ore (t / (hr×m 2 )). As shown in Fig. 3, the productivity of sintered ore produced using pseudo particles at a temperature of 56.0°C, which is 10°C higher than 43.5°C, was significantly higher than the productivity of sintered ore produced using pseudo particles at 47.0°C. From this result and the result in Fig. 2, it can be seen that the productivity of sintered ore can be improved by granulating the sintering raw material by injecting steam into it to produce pseudo particles at a temperature 10°C higher than pseudo particles granulated without injecting steam, and by using these pseudo particles to produce sintered ore.

[0022] Next, the configuration of the drum mixer 32 that can blow in steam of the sintering raw material and efficiently increase the temperature of the pseudo-particles discharged from the drum mixer 32 will be described. Since the drum 33 rotates with the horizontal direction as its rotation axis, the deposition position of the sintering raw material in the drum 33 is tilted toward the rotation direction of the drum 33 with respect to the vertical downward direction. The multiple nozzles 37 are provided at a position 500 mm or more away from the deposition surface of the sintering raw material in the vertical direction. In this way, by providing the multiple nozzles 37 at a position 500 mm or more away from the deposition surface of the sintering raw material in the vertical direction, the temperature of the pseudo-particles can be efficiently increased. The rotation axis of the drum mixer 32 may be approximately horizontal. In addition, in order to efficiently discharge the pseudo-particles, the rotation axis may be tilted so that the discharge port 35 is located vertically below the inlet 34.

[0023] Fig. 4 is a schematic diagram illustrating the configuration of drum mixer 32. Fig. 4(a) is a schematic cross-sectional view of drum mixer 32. Fig. 4(b) is a schematic diagram of steam piping 36. In Fig. 4(b), multiple nozzles 37 are indicated by arrows indicating the ejection direction of steam ejected from each nozzle.

[0024] As shown in FIG. 4, in the drum mixer 32 according to this embodiment, the steam pipe 36 is provided at a position 5000 mm from the inlet 34 of the drum 33, which is the first half of the distance between the inlet 34 and the middle position between the inlet 34 and the discharge outlet 35. In addition, the steam pipe 36 is provided with 15 nozzles 37 at 350 mm intervals. Of these nozzles 37, the first to seventh nozzles from the inlet 34 side are provided so that steam is ejected perpendicularly to the deposition surface of the sintering raw material. The eighth to fourteenth nozzles from the inlet 34 side are provided so as to face the discharge outlet 35 side, inclined at 30° toward the discharge outlet 35 side with respect to the perpendicular line to the deposition surface of the sintering raw material. The nozzle closest to the discharge outlet 35 side is provided so as to be inclined at 45° toward the discharge outlet 35 side with respect to the perpendicular line to the deposition surface of the sintering raw material. That is, of the multiple nozzles 37, more than half of the nozzles are arranged so that the steam ejection direction is tilted toward the exhaust port 35, and the remaining nozzles are arranged so that the steam ejection direction is perpendicular to the deposition surface of the sintering raw material.

[0025] Fig. 5 is a cross-sectional view of a drum mixer showing the positions of multiple nozzles. In order to confirm the effect of the nozzle installation position, a drum mixer shown in Fig. 4 was manufactured with steam piping so that the nozzle position was 100 mm, 300 mm, 500 mm, 1500 mm, and 2500 mm away from the deposition surface of the sintering raw material 62 in the vertical direction, and a steam injection experiment was carried out using the drum mixer.

[0026] FIG. 6 is a graph showing the results of the steam injection experiment. The horizontal axis of FIG. 6 is the position (m) in the drum mixer, and the vertical axis is the temperature (℃) of the sintering raw material. In FIG. 6, the temperature of the sintering raw material is the average temperature of the sintering raw material at each position in the drum mixer shown on the horizontal axis. The conditions of this experiment (steam injection experiment) in all experimental examples (1 to 5) were as follows: steam injection rate 7.5t / h, steam temperature 170℃ (steam pipe pressure: 0.7MPa), raw material (sintering raw material) input rate 730t / h.

[0027] As shown in Fig. 6, in the drum mixers of Experimental Examples 1 and 2, which are located at a vertical distance of less than 500 mm from the deposition surface of the sintering raw materials, the temperature near the inlet was high, but the temperature then decreased, and the temperature of the pseudo-particles discharged from these drum mixers was low. On the other hand, in the drum mixers of Experimental Examples 3, 4, and 5, which are located at a vertical distance of 500 mm or more from the deposition surface of the sintering raw materials, the temperature near the inlet was low, but the subsequent temperature decrease was suppressed, and the temperature of the pseudo-particles discharged from these drum mixers was higher than in Experimental Examples 1 and 2. From these results, it was confirmed that by providing multiple nozzles at a position 500 mm or more vertically away from the deposition surface of the sintering raw materials and blowing steam into the sintering raw materials from these nozzles, the temperature of the pseudo-particles discharged from the drum mixer can be increased compared to the case of providing multiple nozzles at a position less than 500 mm vertically from the deposition surface of the sintering raw materials. As described above, in the drum mixer according to the present embodiment, the temperature of the pseudo-particles can be efficiently increased by injecting steam. Therefore, if the amount of steam injected is the same, the temperature of the pseudo-particles discharged from the drum mixer can be increased, and if the temperature of the pseudo-particles discharged from the drum mixer is the same, the amount of water steam injected can be reduced.

[0028] On the other hand, the moisture content of the pseudo-particles discharged from the drum mixer is also important. If the moisture content of the pseudo-particles discharged from the drum mixer is less than the target moisture content (6.5 mass%), the granulation of the sinter raw material does not proceed, and the particle size of the pseudo-particles after granulation becomes small. If the particle size of the pseudo-particles becomes small in this way, the air permeability of the charging bed formed by the pseudo-particles with a small particle size deteriorates, and the productivity of sintered ore decreases.

[0029] FIG. 7 is a schematic diagram showing a steam pipe. In FIG. 7, multiple nozzles are also shown with arrows indicating the direction of steam emitted from each nozzle. FIG. 7(a) shows a steam pipe of Experimental Example 11 in which multiple nozzles are provided so that the direction of steam emitted is vertically downward. FIG. 7(b) shows a steam pipe of Experimental Example 12 in which the direction of steam emitted from the first to seventh nozzles from the inlet side among the multiple nozzles is vertically downward, the direction of steam emitted from the eighth to fourteenth nozzles from the inlet side is inclined 30° toward the outlet side from the vertically downward, and the direction of steam emitted from the nozzle closest to the outlet side is inclined 45° toward the outlet side from the vertically downward. Figure 7(c) shows the steam pipe of Experimental Example 13, in which the direction of steam emitted from the first to seventh nozzles from the inlet side among the multiple nozzles is inclined at 30° toward the outlet side from the vertical downward direction, the direction of steam emitted from the eighth to fourteenth nozzles from the inlet side is inclined at 45° toward the outlet side from the vertical downward direction, and the direction of steam emitted from the nozzle closest to the outlet side is inclined at 60° toward the outlet side from the vertical downward direction. A steam injection experiment was carried out using a drum mixer in which these steam pipes were installed so that steam was injected from a position 1500 mm away from the pile surface of the sintering raw material in the vertical direction.

[0030] Fig. 8 is a graph showing the results of the steam injection experiment. The horizontal axis of Fig. 8 is the position (m) in the drum mixer, and the vertical axis is the moisture content (mass%) of the sintering raw material, which shows the average moisture content of the sintering raw material at each position in the drum mixer shown on the horizontal axis.

[0031] As shown in Fig. 8, the moisture content of the pseudo-particles granulated by the drum mixer provided with the steam pipe in Experimental Examples 12 and 13 was higher than that of the pseudo-particles granulated by the drum mixer provided with the steam pipe in Experimental Example 11. From these results, it is found that it is preferable to tilt the nozzle so that the ejection direction of the ejected steam faces the ejection port more as the nozzle position approaches the outlet. In addition, since the moisture content of the pseudo-particles was higher in Experimental Example 13 than in Experimental Example 12, it is found that it is preferable that the steam ejection direction of more than half of the nozzles is tilted to face the outlet, and it is more preferable that all of the nozzles are tilted to face the outlet. Since the amount of steam injected from each nozzle is the same, it is preferable to inject the steam into the sintering raw material with the direction of injection of more than half of the total amount of steam tilted to face the exhaust port side, and it is even more preferable to inject the steam into the sintering raw material with the direction of injection of all of the steam tilted to face the exhaust port side.

[0032] As described above, the drum mixer 32, which is the granulation device according to this embodiment, can efficiently heat the sintered raw material by blowing steam into it. Therefore, if the amount of steam used is the same, the pseudo-particles can be heated to a higher temperature, and if the temperature at the outlet side is the same, the pseudo-particles can be heated with a smaller amount of steam used. In this way, by using the granulation device according to this embodiment, the amount of steam used during sintered ore production can be reduced while heating the sintered raw material to a predetermined temperature, thereby improving the productivity of the sintered ore and suppressing the increase in the production cost of sintered ore. [Explanation of symbols]

[0033] 10. Sintered ore manufacturing facility 11 yards 12 Iron-containing raw materials 14 Transport Conveyor 16 CaO-containing raw materials 17 MgO-containing raw materials 18 Setting agent 20 Raw material supply department 22 Blending tank 24 Blending tank 26 Mixing tank 28 Blending tank 30 Transport Conveyor 32 Drum Mixer 33 Drums 34 Inlet 35 Outlet 36 Steam piping 37 Nozzle 38 Water Vapor 39 Transport Conveyor 40 Sintering machine 42 Sintering material supply device 44 Pallet Trolley 46 Ignition Furnace 48 Wind Box 50 Crusher 52 Cooler 54 Sieving device 56 Finished sinter 58 Return Mine 60 Transport Conveyor 62 Sintering materials

Claims

1. A granulation apparatus for granulating a sintering raw material containing an iron-containing raw material, a CaO-containing raw material, and a coagulant, comprising: A cylindrical drum having an inlet through which the sintering raw material is introduced and an outlet through which the granulated sintering raw material is discharged, the drum rotating about a horizontal axis; A steam pipe is provided in only a first half portion of the drum between the inlet and an intermediate position between the inlet and the outlet; a plurality of nozzles connected to the steam pipe for ejecting steam onto the deposition surface of the sintering raw material; The plurality of nozzles are provided at a distance of 500 mm or more from the deposition surface of the sintering raw material, A granulating apparatus, wherein at least half of the plurality of nozzles are provided with steam ejection directions inclined toward the exhaust port.

2. The granulation apparatus according to claim 1, wherein the steam ejection direction of more than half of the plurality of nozzles is inclined so as to face the exhaust port side, and the steam ejection direction of the remaining nozzles is arranged so as to eject steam perpendicular to the deposition surface of the sintering raw material.

3. 3. The granulation apparatus according to claim 1, wherein the steam ejection direction of the plurality of nozzles is tilted so that the closer the nozzle position is to the outlet, the more the nozzle is oriented toward the outlet.

4. A method for producing a granulated sintered raw material, comprising the steps of: granulating a sintered raw material containing an iron-containing raw material, a CaO-containing raw material, and a coagulant using a granulator; The granulating device has an inlet through which the sintering raw material is introduced and an outlet through which the granulated sintering raw material is discharged, and has a cylindrical drum that rotates about a rotation axis in the horizontal direction, In the drum, steam is blown into the sintering raw material from a position 500 mm or more away from the deposition surface of the sintering raw material in the first half portion between the inlet and the midpoint between the inlet and the discharge outlet, to obtain a granulated sintering raw material having a temperature 10° C. or higher than that of the granulated sintering raw material granulated without blowing the steam, A method for producing a granulated sintered raw material, wherein the steam is blown into the sintered raw material at an angle such that the blowing direction of at least half of the total amount of steam is directed toward the discharge port.

5. A method for producing sintered ore, comprising sintering a granulated raw material granulated by the method for producing a granulated sintered raw material according to claim 4 in a sintering machine to produce sintered ore.

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