JP2020084302A - Production method of sintered ore with carbon material and production facility of sintered ore with carbon material ore - Google Patents

Abstract

To provide a method and an apparatus for manufacturing a sintered ore with high quality of carbonaceous material.SOLUTION: When a sintering raw material obtained by mixing a compression-molded carbonaceous material interior-shaped particles for producing sintered ore containing iron ore powder, a raw material containing CaO and a carbonaceous material with raw material particles for producing sintered ore is charged on a pallet of a sintering machine to form a charging layer, a large amount of the carbonaceous material interior-shaped particles is charged on the lower layer side of the charging layer, and a sintered ore is produced by combustion heat of the carbonaceous material contained in the raw material particles for producing the sintered ore. This is formed into a production equipment of sintered ore formed of a raw material hopper, a compression molding machine for compression-molding carbonaceous material interior-shaped particles, a drum mixer for granulating the usual raw material particles for sintering, and a Dwight Lloyd sintering machine for sintering the mixed sintering raw material.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a technology for producing a sintered ore used as a raw material for iron making in a blast furnace or the like, and specifically, a method and a method for producing a sintered ore by using a carbon material-containing molded body as a raw material for sintering. It concerns equipment.

In the blast furnace ironmaking method, iron-containing raw materials such as iron ore and sinter are mainly used as iron sources at present. Here, the above-mentioned sintered ore is, in addition to iron ore having a particle size of 10 mm or less, a SiO ₂ containing raw material made of silica stone, serpentine, refined nickel slag or the like, or a sub raw material made of CaO containing raw material such as limestone or quick lime. , A suitable amount of water is added to a granulation raw material such as solid fuel (carbonaceous material) that is a coagulating material such as powder coke or anthracite, and mixed using a drum mixer or the like to be granulated and sintered as pseudo particles. After being used as a raw material, the sintering raw material is placed on a pallet that moves circularly in a sintering machine, the carbonaceous material contained in the pseudo particles is burned and sintered, and the obtained sintered cake is crushed. It is a kind of agglomerated ore that has been sized and recovered as a product with a certain particle size or more.

By the way, in recent years, as the above-mentioned agglomerated ore, one in which an iron source such as iron ore and dust and a carbonaceous material such as coke are arranged close to each other has attracted attention. The reason is that, for example, when an iron source such as an iron ore and a carbonaceous material are placed close to each other in one agglomerated ore, a reduction reaction (exothermic reaction) on the iron source side and a gasification reaction (endothermic reaction) on the carbonaceous material side. ) And (2) occur repeatedly at a high speed, the iron-making efficiency is improved and the temperature inside the furnace such as the blast furnace can be lowered.

The agglomerated ore is, for example, a carbonaceous material interior for sinter ore production, which is a pseudo particle formed by forming an outer layer made of iron ore powder and a CaO-containing raw material around a carbonaceous material nucleus disclosed in Patent Document 1. When the sintering raw material obtained by mixing the granulated particles with the normal granulated particles is charged on the pallet of the sintering machine to form the charging layer, the carbon material-containing granulated particles are mixed with the charging layer. There is a carbonaceous material-containing sintered ore that is charged in a large amount in the lower layer side to produce a sintered ore by the combustion heat of the carbonaceous material contained in the usual granulated particles.

In this technique, as the carbon material-containing granulated particles, coke particles having a particle size of 3 mm or more are used for the carbon material core, and pellet feed having a controlled particle size is used for the iron ore powder. Further, only a method of granulating granulated particles with a drum mixer or a pelletizer is disclosed.

Patent No. 5790966

However, the method of Patent Document 1 has a limitation on the particle size of the pellet feed or the carbonaceous material, which is a raw material of the granulated particles containing carbonaceous material.
In order to use a pellet feed with a particle size adjusted to a specific range, control the particle size distribution of the pellet feed in the market, and adjust the size of undersize and oversize particles to remove it. Or it was necessary to remove coarse particles by crushing. On the other hand, the particle size is 3
In order to use coke particles of mm or larger, it is general to select coke with a 3 mm sieve. However, the coke is usually handled outdoors, and thus is in a humidity-controlled state. When it is attempted to select such a humidity control raw material with a 3 mm sieve mesh, powder adheres to the mesh and the sieving efficiency is significantly reduced, which makes it difficult to obtain the necessary amount.

Therefore, the present invention has been made in view of the above-mentioned problems that the prior art has, and its purpose is to relax the constraint conditions of the particle size of the raw material, to obtain a high-strength carbonaceous material-containing particles, It is to propose a method for producing a high-quality carbon material-containing sintered ore. At the same time, it is to provide a manufacturing facility suitable for the method.

As a result of intensive studies to solve the above-mentioned problems, the inventors have found that it is effective to form carbonaceous material-containing molded particles by molding by applying an external force, and the present invention Came to develop. That is, the present invention is, first of all, formed by mixing compression-molded carbonaceous material-containing molded particles for producing a sintered ore containing iron ore powder, a CaO-containing raw material and a carbonaceous material, with raw material particles for producing a sintered ore. When the sintering raw material is charged on the pallet of the sintering machine to form the charging layer, many of the carbon material-containing molded particles are charged in the lower layer side of the charging layer to produce the sintered ore. We propose a method for producing a carbonaceous material-containing sintered ore characterized by producing a sintered ore by the combustion heat of the carbonaceous material contained in the raw material particles.

In addition, about the manufacturing method of the carbonaceous material-containing sintered ore according to the present invention,
a. The raw material particles for producing the sinter ore are granulated with a drum mixer, and the particle size is smaller than the carbon material-containing molded particles,
b. The iron ore powder is a powdered iron ore with a particle size of 1 mm or less,
c. In the range from the outer surface of the carbonaceous material-containing molded particles to 2 mm, the melting point is 1200° C. or more and 1500° C. or less,
d. The carbonaceous material is coke particles having a particle size of 8 mm or less,
e. The carbonaceous material-containing molded particles have a particle size of 8 mm or more,
f. The carbonaceous material-containing molded particles are iron ore powder, a CaO-containing raw material as a melting point adjusting agent, and a carbonaceous material that are molded using a compression molding machine,
Is considered to be a more preferable solution.

In addition, the present invention is secondly the equipment used in the method for producing any of the above carbonaceous material-containing sintered ore, comprising a hopper for holding iron ore powder, a hopper for holding a CaO-containing raw material, and a charcoal. And at least one hopper for holding the material, at least, iron ore powder, CaO-containing raw material and a raw material containing a carbonaceous material are mixed, compressed and molded to form a carbonaceous material-containing molded particle for sinter production. A compression molding machine, a drum mixer that granulates a normal raw material for sinter ore into raw material particles for producing sinter, and the above-mentioned carbonaceous material-containing molded particles and the above raw material particles for producing sinter are mixed. A charcoal having a surge hopper held as a sintering raw material, and a Dwightroid type sintering machine for sintering the sintering raw material charged from the surge hopper to obtain a sintered ore. Providing manufacturing facilities for material-containing sinter.

According to the present invention, it becomes possible to mold high-strength carbonaceous material-containing molded particles without worrying about the particle size of the carbonaceous material or iron ore powder used. In particular, since such a carbonaceous material-containing molded particle can be used to produce a sintered ore using a general Dwightroid type (DL) sintering machine, it is possible to produce a large amount and inexpensive carbonaceous material-containing sintered ore. Will be possible. Further, the carbonaceous material-containing sintered ore of the present invention has a structure in which the iron-containing raw material and the carbonaceous material are arranged in close proximity in addition to having sufficient strength for use as a raw material for a blast furnace, etc. It improves the reaction efficiency, lowers the temperature in the furnace, reduces the fuel ratio, and contributes to the reduction of manufacturing cost.

FIG. 1 is a conceptual diagram of carbonaceous material-containing molded particles (A) showing one embodiment of the present invention and carbonaceous material-containing granulated particles (B) according to a conventional technique. It is a manufacturing equipment conceptual diagram (A) which shows one Embodiment of this invention, and the manufacturing equipment conceptual diagram (B) of a prior art.

FIG. 1 shows a conceptual diagram of carbonaceous material-containing molded particles (A) showing an embodiment of the present invention and carbonaceous material-containing granulated particles (B) according to the conventional technique described in Patent Document 1. As shown in FIG. 1A, the carbon material-containing molded particle 1 of the present invention has a structure in which the carbon material 2 is dispersed in the mixed phase 3 of the iron ore powder and the CaO-containing raw material by compression molding. For the compression molding, a twin roll type or flat plate type briquette machine, a cylinder press type or the like can be used. Reference numeral 4 in the drawing is a sintering boundary surface indicating a boundary between a carbonaceous material remaining region (nucleus) and a carbonaceous material disappearing region (outer layer) after sintering which will be described later. On the other hand, what is shown in FIG. 1B is a prior art, and it is granulated into a material having a mixed phase 3 of iron ore powder and CaO-containing raw material as an outer layer containing no carbon material around a carbon material 2 nucleus of 3 mm or more. It is the carbon material-containing granulated particles 5.

It has been known from conventional general knowledge that if the coating layer thickness from the carbonaceous material 2 to the surface of the molded body is 2 mm or more, the combustion and disappearance of the carbonaceous material 2 can be prevented in the sintering process. In this respect, in the carbonaceous material-containing molded particles of the present invention, as is clear from FIG. 1A, the carbonaceous material 2 is distributed also in the vicinity of the surface layer, and voids are generated due to burning and disappearance in the sintering process. However, there is a sound carbonaceous material remaining region even after sintering. Further, in the case of the present invention, a molded product having sufficient hot strength is obtained despite such voids. It is considered that the reason for this is that since the molded body is forcibly compressed, the decrease in hot strength due to the formation of voids can be compensated.

Here, as the iron ore powder used in the present invention, it is preferable to use powdery iron ore having a particle size of 1 mm or less. Here, the particle size of 1 mm or less means that the entire amount passes through a sieve having a nominal opening of 1 mm defined in JIS Z8801-1:2006.

If the iron ore powder used in the present invention has a particle size within the above range, in addition to pellet feed, a sinter feed containing a larger particle size of 10 μm or less than the pellet feed, mill scale, converter exhaust gas recovery dust ( OG dust), tailing generated during beneficiation, and crushed products thereof, or may be a mixture of them in a pellet feed. A mixture mainly composed of pellet feed or a pellet feed is preferable. Pellet feed is a fine grain ore with a size of 1 mm or less of 90% or more, is mainly composed of high-quality (high Fe, low gangue) hematite or magnetite, and is excellent in that it can be obtained in large quantities at low cost.

However, the melting point of the above-mentioned magnetite, particularly high-grade magnetite, is as high as about 1580° C., which is much higher than the suitable sintering temperature (1200 to 1400° C.) for obtaining high-quality sinter, It does not melt at the sintering temperature of 1, that is, the sintering reaction does not occur.

The present invention reduces the melting point of the mixed phase of the iron ore and the CaO-containing raw material by adding the CaO-containing raw material, which is a melting point adjuster, to the iron ore powder described above, so that the temperature at the time of sintering (1200°C or higher) is early. To form a fusion layer on the surface layer of the pseudo particles, and by acting the fusion layer as an oxygen barrier layer, it is possible to prevent combustion and disappearance of the carbonaceous material dispersed inside the carbonaceous material-containing molded particles. The characteristic is that the carbonaceous material remains.

Further, according to the present invention, with the above structure, the carbonaceous material remaining region (nucleus) can be present even if air invades during firing of the sintered ore. This is because due to the oxygen blocking effect of the surface layer (outer layer) of the carbon material-containing molded particles (pseudo particles), the invasion O ₂ does not reach the carbon material contained in the nucleus inside the sintering boundary surface 4, and the surface layer portion This is because it is considered that the carbonaceous material can remain because the inside of the outer layer is basically held by the CO gas in the reducing atmosphere due to the reaction of C with the invading O ₂ .

Here, the melting point of the mixture of the iron ore and the melting point adjusting agent adjusted above is preferably in the range of 1200 to 1500°C, and more preferably in the range of 1200 to 1400°C from the viewpoint of promoting melting on the sintering machine. is there. This is because if the temperature is less than 1200° C., a melt is not generated, and calcium ferrite, which has the highest strength and relatively high reducibility among the constituent minerals of the sintered ore, is not generated. On the other hand, above 1500° C., it does not melt on the sintering machine and does not fuse with the sinter structure mainly composed of calcium ferrite.

The CaO-containing raw material added as the melting point adjuster is selected from quicklime (CaO), slaked lime (Ca(OH) ₂ ), calcium carbonate (CaCO ₃ ), and dolomite (CaMg(CO ₃ ) ₂ ). It is preferably composed of one kind or two or more kinds. CaO is particularly preferable. The amount of CaO-containing raw material added is, in terms of CaO, the pellet feed (PF) as the iron ore powder used for the outer layer, which contains a small amount of gangue components such as Anglo American-PF (hematite (Fe ₂ O ₃ )). 97.7 mass%), it may be determined from the Fe ₂ O ₃ —CaO binary system phase diagram. In addition, when using iron ore powder with a large amount of gangue components, the addition amount as CaO components is determined using a SiO ₂ —Fe ₂ O ₃ —CaO ternary phase diagram that considers SiO ₂ , which is a gangue component. Just decide. In addition to quick melting point, quick lime acts as a binder.

In the present invention, it is preferable to adjust the water content to about 4 to 10 mass% from the viewpoint of improving moldability. The reason is that when the water content is 4 mass% or more, the strength after molding becomes higher, and when the water content is 10 mass% or less, molding defects can be further reduced.

Further, as the binder, pregelatinized starch, bentonite, polyvinyl alcohol, magnesium lignin sulfonate, polyacrylamide, CMC (carboxymethyl cellulose) or the like can be used. For example, it is preferable to add 0.1 to 10 mass% of pregelatinized starch. The reason for this is that when the content of pregelatinized starch is 0.1 mass% or more, the strength after molding further increases, and when it exceeds 10 mass%, the effect of increasing the strength after molding begins to saturate, and it becomes uncomfortable to increase the addition cost. This is because there is a risk.

As the carbonaceous material, it is preferable to use a carbonaceous material having a low volatile content such as coke grains and anthracite such as Hongay charcoal. The particle size of the carbonaceous material is preferably 8 mm or less. Here, the particle size of 8 mm or less means that all the particles pass through a sieve having a nominal mesh size of 8 mm defined in JIS Z8801-1:2006. In the conventional method, since one granulated particle always requires one carbonaceous material core, it was necessary to regulate the coke to have a particle diameter of 3 mm or more. However, in the present invention, the carbonaceous material remains at the center of the molded particle. Since it is effective if one or more carbon material grains are present in the layer (nucleus), the grain size is preferably 8 mm or less, and the lower limit is not limited. As a characteristic of compression molding, since the center of the carbonaceous material particle cannot exist closer to the outer surface of the molded material than the radius of the carbonaceous material particle, the carbonaceous material preferably has a particle size distribution of 2.8 mm or more. The presence of 20% or more on the mass basis is more preferable because the ratio of the carbonaceous material that disappears during sintering in a place within 1 to 2 mm from the outer surface of the molded particle is reduced and the strength is improved. Here, when the particle size exceeds 2.8 mm, it means that the particle size does not pass through a sieve having a nominal opening of 2.8 mm defined in JIS Z8801-1:2006. More preferably, the arithmetic average particle diameter is in the range of 1.5 mm or more and 4.0 mm or less.

Further, in the region where the carbonaceous material burns and disappears after sintering, the thickness of the outer layer of the pseudo particles is preferably 2 mm or more at the thinnest place. The reason is that if it is less than 2 mm, the void strength of the carbonaceous material that has disappeared may reduce the hot strength of the molded particles. Usually, in compression molding, since the density other than in the compression direction varies and the shape does not become a true sphere, the thickness of the molded particles from the surface layer to the sintered boundary layer is not uniform. Since the hot strength of the sintered layer is considered to be proportional to the thickness of the sintered layer, it is evaluated based on the thinnest portion of the outer layer. Since the molded particles are usually heated from the outside, it is difficult for the temperature to rise during heating toward the center. Therefore, in order to increase the thickness of the outer layer, the melting point of the outer layer can be adjusted to a low value or the compression force can be decreased. The thickness of the outer layer is more preferably in the range of 3 to 7 mm from the viewpoint of oxygen barrier and hot strength.

Further, the particle size of the carbonaceous material-containing molded particles (pseudo particles) of the present invention is 7 mm from the sum of the minimum value of the sphere-equivalent diameter of the carbonaceous material remaining region (nucleus) and the minimum value of the outer layer. However, from the viewpoint of suppressing the reaction of the carbonaceous material on the sintering machine, in consideration of the temperature distribution in the formed particles, the particle diameter is not less than a sufficient temperature to reach the center of the particles in the sintering process, that is, 8 mm or more. Preferably. It is more preferably 10 mm or more, and further preferably 20 mm or more. Here, the particle diameter is the equivalent spherical diameter.

Further, the carbonaceous material-containing molded particles of the present invention are required to be segregated into the lower layer side of the sintered layer at the time of charging the sintering raw material into the sintering machine described later. The particle size is preferably larger than (granulated particles). Here, the above-mentioned normal granulated particles are granules of auxiliary raw materials including iron ore powder, carbonaceous materials and CaO-containing raw materials, and granules of 2 to 4 mm (arithmetic mean diameter) by a drum mixer or pelletizer. This refers to pseudo particles that are granulated into particles (the same applies hereinafter). The particle size of the granulated particles in the present invention means the particle size measured by sieving.

Next, a carbonaceous material-containing molded particle of the present invention and a method for producing a sintered ore using the molded particle as a sintering raw material will be described.
FIG. 2A shows an example of a method for producing a carbon material-containing sintered ore using the carbon material-containing molded particles according to the present invention. On the other hand, FIG. 2B shows an example of a method for producing a carbonaceous material-containing sintered ore using the conventional carbonaceous material-containing granulated particles described in Patent Document 1. In the example of FIG. 2A, the iron ore powder 8 having a particle diameter of 1 mm or less, the CaO-containing raw material 9 as a melting point adjusting agent, and the carbonaceous material (coke powder) 10 having a particle diameter of 8 mm or less are compressed by a compression molding machine. It is loaded into a certain briquette machine 11 and compression-molded to obtain carbonaceous material-containing molded particles (pseudo particles) having a particle diameter of 8 mm or more. Here, the compressive force of the briquette machine is preferably 0.5 tonf/cm (490 kN/m) or more as the axial pressure (load per axial length of the roll). The reason is that a sufficient hot strength can be obtained by doing so. Since an excessive load leads to an increase in size of the device, a more preferable axial pressure is in the range of 0.7 to 1.8 tonf/cm (690 to 1760 kN/m).

Next, the carbonaceous material-containing molded particles (pseudo particles) obtained as described above are obtained by agitating the ordinary raw material 6 for producing a sintered ore with a drum mixer 7 and granulating it to produce a normal sintered ore. The particles are mixed with the granulated particles (pseudo particles) for mixing, and both particles are mixed and carried into the surge hopper of the sintering machine 13, and are loaded from the surge hopper onto a pallet that circulates in the sintering machine. Since the carbonaceous material-containing molded particles (pseudo particles) have a larger particle size than ordinary granulated particles for sinter production (pseudo particles), they segregate at the time of charging and the temperature during sintering becomes the upper layer. Since a large amount is deposited on the side of the middle layer and the side of the lower layer, which tends to be higher than the side, the sintering reaction has a characteristic that the reaction easily proceeds sufficiently.

As described above, since the carbonaceous material-containing sintered ore of the present invention can be produced using a general DL sintering machine, it can be mass-produced at low cost. In addition, since iron ore powder and coke coke which are raw materials for the outer layer can be obtained inexpensively and in large quantities without worrying about the particle size, there is no restriction on production. In addition, it is possible to suppress capital investment such as a sieving machine and a crusher.

Further, a sinter production facility suitable for producing the carbonaceous material-containing sinter of the present invention will be described.
In order to carry out the present invention, as shown in FIG. 2A, at least one of a hopper 8 for holding iron ore powder, a hopper 9 for holding a CaO-containing raw material, and a hopper 10 for holding carbonaceous material is provided. , And at least iron ore powder, CaO-containing raw material, and raw material containing carbonaceous material are mixed, compressed, and molded into a carbonaceous material-interior molded particle for sintering ore production, and normal sintering. A drum mixer 7 that granulates the raw material 6 for ore into raw material particles for producing a sintered ore, and the surge in which the above-mentioned carbonaceous material-containing molded particles and the above raw material particles for producing a sintered ore are mixed and held as a sintering raw material. It is necessary to use a manufacturing facility including a hopper (not shown) and a Dwightroid-type sintering machine 13 that sinters the sintering raw material charged from the surge hopper into a sintered ore. is there. In the present invention, the sintering raw materials are adjusted by at least two rows of apparatus groups, which are connected by a raw material conveying line (not shown). The carrying line in the present invention is not particularly limited as long as it can carry the powder at a constant speed, but a belt conveyor or the like can be preferably used.

First, in the production facility of the present invention, a hopper 8 for holding iron ore powder, a hopper 9 for holding a CaO-containing raw material, and a carbonaceous material for holding carbonaceous material-containing molded particles for production of sinter ore. At least one hopper 10 is provided and a compression molding machine is provided. As the compression molding machine, a twin roll type or flat plate type briquette machine, a cylinder press type, or the like can be used. If necessary, a hopper (not shown) for holding an auxiliary material such as pregelatinized starch can be provided. The compression molding machine of the present invention may be any machine that can obtain molded particles of a predetermined size with a predetermined compression force (load).

In addition, the production facility of the present invention is provided with a drum mixer 7 as a granulating device for adjusting ordinary raw material particles for producing a sintered ore. As the drum mixer of the present invention, a known drum mixer can be used. The sinter ore raw material 6 for granulation may be cut out from a raw material hopper used for adjusting the above-mentioned carbonaceous material interior molding particles, or cut out from a separately prepared raw material hopper and conveyed. You may. As the raw material 6 used for the normal raw material particles for producing a sintered ore, those generally used as a sintering raw material for a sintered ore can be widely used.

Further, the production facility of the present invention is equipped with a Dwightroid type sintering machine having a surge hopper which mixes and holds the above carbonaceous material-containing molded particles and the above-mentioned raw material particles for producing a sintered ore as a sintering raw material. The Dwightroid type sintering machine is preferably a downward suction type Dwightroid type sintering machine.

As an invention example, 93 mass% of iron ore powder (≦1 mm=100%, −1+0.25 mm=15%), 5 mass% of quicklime as a CaO source, and powder coke (arithmetic mean particle size 1. 5mm, >2.8mm=20%) to 2mass% of raw material, 4mass% of pregelatinized starch as a binder is added, and a briquette machine of 1.2cc (sphere equivalent diameter of about 13mm) is molded using a briquette machine. did. At that time, the load was adjusted to 0.8 tonf/cm (780 kN/m) as the axial pressure and adjusted to 8 mass% as the raw material water content. It should be noted that the iron ore was conditioned in a humidity-controlled state collected in a yard, and the water content was adjusted appropriately before use. The water content of the quicklime and coke powder was 0 mass%. As shown in FIG. 1A, coke powder was dispersed inside the briquette, and it was confirmed that sufficient coke was dispersed in the core of the briquette (inside the sintering boundary surface). Here, the melting point of the mixed phase of iron ore and CaO was 1500°C.

This molded briquette was charged into an electric furnace kept at 1200° C., held for 2 minutes, and then taken out of the furnace. When the crush strength of the briquettes after heating was measured with a uniaxial compression tester, the strength was about 20 to 30 kgf (196 to 294 N). The outer layer surface had a fragile structure, and peeling powder was generated, but the inner part had a healthy structure. From the observation of the cross section, the equivalent sphere diameter of the core in which the carbonaceous material remained was about 4 mm, and the outer layer was about 2.5 mm where the outer layer was thin.

As a comparative example, according to the conventional method described in Patent Document 1, 93 mass% of iron ore (≦1 mm=100%, −1+0.25 mm=15%) and 5 mass of quicklime as a CaO source were used according to the flow of FIG. 2B. %, powder coke (arithmetic mean particle size 1.5 mm, >2.8 mm=20%), 2 mass% of raw material was supplied to a disk pelletizer having a diameter of 1.2 m, and granulated while adding water. Here, the iron ore was used after adjusting the moisture content of the iron ore sampled in the yard and adjusting the moisture content. The water content of the quicklime and coke powder was 0 mass%.

Among the obtained granulated particles, the ratio satisfying the target size of 10 mm was as low as about 10% to 50%, and the granules were granulated without containing small carbonaceous material-containing granulated particles or carbonaceous material nuclei. Many things were generated. The carbon material-containing granulated particles having a size of about 10 mm were placed in an electric furnace kept at a temperature of 1300° C., held for 1.5 minutes, and then taken out of the furnace. When the crush strength of the carbon material-containing granulated particles after heating was measured by a uniaxial compression tester, the crush strength was about 5 to 10 kgf (4.9 to 9.8 N).

The carbonaceous material-containing molded particles of the invention example produced in Example 1 and ordinary granulated particles were charged into a sintering experimental pot having an inner diameter of the raw material charging part of 300 mmφ and a height of 400 mm. In the lower layer side ⅓ (133 mm) of the raw material charging part, the carbon material-containing granulated particles and the normal granulated particles were mixed in a mass ratio of 1:1 to obtain the carbon material-containing granulated particles in the normal granulated particles. The mixture is uniformly mixed so as to be embedded in the above, and the upper layer side 2/3 (267 mm) is charged with normal granulated particles, and then the upper layer surface of the charging layer is ignited and placed under the test pot. The air above the test pot was sucked by the blower arranged on the side to be introduced into the charging layer to burn the carbonaceous material in the sintering raw material. Here, the reason why the carbonaceous material-containing granulated particles were charged in the lower layer side 1/3 so as to be embedded in the ordinary granulated particles was that only the combustion heat of the surrounding ordinary granulated particles was used. This is because a sintering reaction is allowed to proceed between the granular particles and the outer layer of the carbon material-containing granulated particles to obtain a sintered sinter that is provided without burning the carbon material of the central core. This is because it is advantageous on the lower layer side ⅓ where the temperature is likely to rise during binding.
After the sintering experiment, the carbonaceous material-containing sinter obtained from the lower layer side 1/3 (133 mm) of the raw material charging section and the normal firing obtained from the upper layer side 2/3 (267 mm) of the raw material charging section With respect to the slag, the reducibility index (reduction rate) RI was measured by the method specified in JIS M8713:2009, and the reduction dusting index RDI was measured by the method specified in JIS M8720:2009.

The RDI of the upper layer of the raw material was about 35, and the RDI of the lower layer was 40. On the other hand, the reducibility (RI) was 68 in the upper layer portion and 72 in the lower layer portion. It is considered that the reason why the RDI of the lower layer was higher than that of the upper layer was that the briquette became porous due to the disappearance of a part of the carbonaceous material in the briquette and the strength after reduction was reduced. On the other hand, since it is porous, it has become possible to manufacture a sinter that is highly reducible.

The technique of the present invention is not limited to the examples described above, for example, as a sintering heat source, in addition to the carbonaceous material added to the sintering raw material, a sintering technique of supplying a gaseous fuel, Further, it can be applied to a sintering technique in which oxygen is enriched and supplied.

1 Carbon material interior molding particles 2 Carbon material (coke grain)
3 Mixed Phase of Iron Ore Powder and CaO-Containing Material 4 Sintering Interface 5 Carbonaceous Material Granulated Particles 6 Ordinary Sintered Raw Material 7 Drum Mixer 8 Iron Ore Powder Hopper 9 CaO-Containing Material Hopper 10 Carbon Material (Coke) Powder) hopper 11 Compression molding machine (briquette machine)
12 Disc pelletizer 13 Sintering machine

Claims (8)

A sintering raw material obtained by mixing compression-molded carbonaceous material-containing molded particles for sinter ore production, which contains iron ore powder, CaO-containing raw material and carbonaceous material, with a sintering machine pallet When charging on top to form the charging layer,
Charcoal characterized in that a large amount of the carbonaceous material-incorporated molded particles are charged in a lower layer side of a charging layer, and a sintered ore is produced by combustion heat of the carbonaceous material contained in the raw material particles for producing a sintered ore. A method for producing a material-containing sintered ore. The method for producing a carbon material-containing sintered ore according to claim 1, wherein the raw material particles for producing a sinter ore are granulated by a drum mixer and have a particle size smaller than that of the carbon material-containing molded particles. .. The method for producing a carbonaceous material-containing sintered ore according to claim 1 or 2, wherein the iron ore powder is a powdery iron ore having a particle size of 1 mm or less. The range of 2 mm from the outer surface of the carbonaceous material-containing molded particles has a melting point of 1200° C. or more and 1500° C. or less, and the carbonaceous material-containing sintered ore according to any one of claims 1 to 3, Production method. The method for producing a carbonaceous material-containing sintered ore according to any one of claims 1 to 4, wherein the carbonaceous material is coke particles having a particle size of 8 mm or less. The method for producing a carbonaceous material-containing sintered ore according to claim 1, wherein the carbonaceous material-containing molded particles have a particle diameter of 8 mm or more. 7. The carbonaceous material-containing molded particle is a molded body obtained by molding iron ore powder, a CaO-containing raw material as a melting point adjusting agent, and a carbonaceous material using a compression molding machine. The method for producing a carbon material-containing sintered ore according to item 1. A facility used in the method for producing a carbonaceous material-containing sintered ore according to any one of claims 1 to 7,
At least one hopper that holds the iron ore powder, a hopper that holds the CaO-containing raw material, and a hopper that holds the carbonaceous material,
A compression molding machine that mixes at least iron ore powder, a CaO-containing raw material and a raw material containing carbonaceous material, compresses, and molds them to obtain carbonaceous material-containing molded particles for producing sinter,
A drum mixer that granulates a raw material for normal sinter ore into raw material particles for sinter production,
It has a surge hopper in which the carbonaceous material-containing molded particles and the raw material particles for producing the sintered ore are mixed and held as a sintering raw material, and the sintering raw material charged from the surge hopper is sintered and fired. An apparatus for producing a carbonaceous material-containing sintered ore, comprising a Dwightroid type sintering machine for forming mine.

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