JP4681688B2 - Iron ore sintering carbon - Google Patents

Description

  The present invention relates to a carbon material that can be used as a fuel when iron ore is sintered to produce a sintered ore.

  In the production of sintered ore, first, powdered iron ore is used as the main raw material, mixed raw materials such as limestone, quartzite, serpentinite, and other raw materials, solid fuel, return ore are mixed and granulated using a drum mixer or the like. Pseudo particles are used, and after mixing the mixed material pseudo particles into the sintered pallet in layers, the solid fuel in the surface layer mixed material is ignited, and the combustion is sequentially transferred to the lower layer by sucking air from below the sintered pallet. The charged blended raw materials are fired into sintered ore.

  Conventionally, powder coke has been used as a solid fuel for producing sintered ore. Powdered coke is obtained by sieving the bulk coke produced in the coke oven, which has a small particle size and cannot be charged into the blast furnace.

  Further, as solid fuel for iron ore sintering other than powder coke, for example, those relating to Patent Documents 1 and 2 below are known.

  Patent Document 1 describes that 10% by weight or more of a fuel (fuel coal material) to be blended in the production of sintered ore is blended with char obtained by pyrolyzing coal in a temperature range of 300 ° C to 900 ° C. Yes.

  In Patent Document 2, a mixture of powdered iron ore and coal is heated and held at 300 ° C. or more and 900 ° C. or less sufficient for the coal to thermally decompose, and a solid substance made of char and partially reduced ore is obtained. A fuel for sintering is disclosed.

JP-A-5-230558 JP-A-5-230557

  In recent years, the price of caking coal, which is a raw material for anthracite and powdered coke, is increasing. Therefore, there is a need for a cheaper alternative solid fuel that can be used for sinter production.

  In addition, carbon dioxide emissions are being reduced due to environmental problems, and in order to achieve this purpose, reduction of fuel intensity is required. Therefore, an alternative solid fuel that is superior in combustion efficiency to a conventional solid fuel is desired.

  Furthermore, an increase in the amount of blast furnace tapping and an improvement in the tapping ratio are achieved. For this purpose, it is essential to increase the production of sintered ore and improve the quality of the ore. Accordingly, there is a need for a new method for producing sinter that enables improvement in the production rate and product yield of the sinter than in the case of using a conventional solid fuel. In this regard, Patent Document 1 or 2 does not disclose any improvement in the production rate of the sintered ore and the product yield.

  Furthermore, as with carbon dioxide, it is also required to reduce nitrogen oxide (NOx) in the exhaust gas from the sintering machine.

  The present invention has been made in view of such circumstances, and is cheaper and superior in combustion efficiency than conventionally used sintering fuels, and improves the production rate and product yield of sintered ore. An object of the present invention is to provide a solid fuel for sintering iron ore, that is, a carbon material, which can reduce the amount of nitrogen oxide emission during production of sintered ore.

The present invention has been made in view of the above problems, and the gist of the present invention is (1) a carbon material for use as a solid fuel for iron ore sintering, which has the following properties: Charcoal material.
(i) the reaction start temperature is 550 ° C. or lower,
(ii) Volatile content (VM) is 1.0% or more
(iii) The atomic ratio (H / C) of hydrogen to carbon is 0.040 or more,
(iv) The amount of pores with a pore diameter of 0.1 to 10 μm measured by mercury porosimetry is 50 mm ³ / g or more. (2) The charcoal according to (1), wherein the charcoal further has the following properties: Wood.
(v) the maximum reaction rate temperature is 600 ° C. or less,
(vi) The reaction rate at 1000 ° C. is 0.19 min ⁻¹ or more. (3) The carbon material further has the following properties. The carbon material according to (1) or (2).
(vii) The micro strength index (MSI _0.21 ) is 20 or more. (4) The charcoal material according to (1) or (2), wherein the charcoal material is manufactured using sub-bituminous coal or lignite.
(5) The carbon material according to (3), wherein the carbon material is manufactured using sub-bituminous coal or lignite.
(6) A method for producing a sintered ore, wherein the carbonaceous material according to (1) or (2) is used as a solid fuel.
(7) A method for producing a sintered ore, wherein the carbonaceous material according to (3) is used as a solid fuel.
(8) A method for producing a sintered ore, wherein the carbonaceous material according to (4) is used as a solid fuel.
(9) A method for producing a sintered ore, wherein the carbonaceous material according to (5) is used as a solid fuel.

  In this specification, the reaction start temperature refers to the following temperature. That is, a predetermined weight (10 to 20 mg) of a sample adjusted to a predetermined particle size (0.15 to 0.25 mm) is put on a thermobalance, and the temperature is increased at a predetermined temperature increase rate (10 ° C./min) in an air atmosphere. And measure weight loss. Here, the temperature at which the weight reduction rate stably exceeds 0.002 (1 / min) is referred to as the reaction start temperature.

  In the present specification, the temperature at which the slope of the weight loss curve is maximized (the temperature at which the weight loss per unit time is maximized) is referred to as the maximum reaction rate temperature.

  Further, in this specification, the reaction rate at 1000 ° C. means that a sample adjusted to a predetermined particle size (0.15 to 0.25 mm) is placed in a thermobalance and a predetermined weight (10 to 20 mg) is placed in a nitrogen atmosphere. It refers to the weight reduction ratio per unit time (ratio of weight reduction amount to initial weight) (1 / min) in the initial stage where the temperature is raised to 1000 ° C. and then the atmosphere is an air atmosphere.

  Moreover, the volatile matter (VM) of this specification can be measured by the method as described in JISM8812.

  The atomic ratio of hydrogen to carbon (H / C) is calculated based on the weight percentages C% and H% of carbon and hydrogen measured by elemental analysis. H / C = (H% / 1) / ( C% / 12).

  In the present specification, the amount of pores is measured by a mercury intrusion method. The mercury intrusion method is a technique for obtaining information such as the pore size distribution from the relationship between the pressure and the amount of injected mercury by injecting mercury into the pores of a sample such as porous particles while applying pressure. The pore volume distribution by the mercury intrusion method is determined using a mercury porosimeter which is a device that measures the pore volume distribution with a pore size of 0.01 to 100 μm in a solid substance and is generally used. Can do.

Moreover, in this specification, the micro strength index (MSI _0.21 ) means that a 0.5 to 1.0 mm sample 2 g and 12 φ7.9 mm iron balls are placed in a cylindrical container of φ24.2 × L300 mm at 25 rpm. After applying an impact of 800 rotations, the weight percentage with respect to the sample of +0.21 mm (0.21 mm or more) when the weight is measured with a 70 mesh (0.21 mm) sieve.

  According to the present invention, it is cheaper than the conventionally used sintering fuel, has excellent combustion efficiency, can improve the production rate of the sintered ore, and the yield of the product, and at the time of producing the sintered ore It is possible to provide a fuel for sintering iron ore that makes it possible to achieve a reduction in nitrogen oxide emissions.

It is the schematic of the manufacturing process of the carbonaceous material of embodiment of this invention. It is a graph which shows the pore volume distribution of Example H and Comparative Example A. It is a graph which shows the relationship between the weight of Example H and Comparative Example A, and temperature. It is a graph which shows the weight reduction rate of Example H and Comparative Example A, and the relationship of temperature. It is the schematic of the manufacturing process of the sintered ore using the carbonaceous material of embodiment of this invention. It is a schematic diagram which shows the state of the sintering raw material of a sintering process.

  The charcoal material of the embodiment of the present invention is manufactured by, for example, using subbituminous coal or lignite as a raw material, and pyrolyzing it using a pyrolysis furnace such as a rotary kiln. The subbituminous coal and lignite can be obtained much cheaper than powdered coke, and can be made cheaper than conventional solid fuels even in consideration of production costs and the like. In addition, the raw material of the carbonaceous material which concerns on embodiment of this invention is not limited to this, Coals (non-slightly caking coal, general coal, subbituminous coal, lignite etc.) whose coalification degree is lower than caking coal ), More specifically, coal having an oxygen / carbon atomic ratio (O / C) of 0.07 or more can be used as a raw material. Of these, sub-bituminous coal or lignite is preferable because the production rate and product yield are further improved when a sintered ore is produced using the carbonaceous material of the embodiment of the present invention.

  First, manufacture of the carbonaceous material of the embodiment of the present invention will be specifically described with an example. FIG. 1 is a schematic view of a manufacturing process of a carbonaceous material 1 according to an embodiment of the present invention. Reference numeral 2 denotes a pyrolysis furnace (rotary kiln), which is a closed container in which an internal space cut off from an atmospheric atmosphere by a heat insulating wall is formed. . 3 is a preheating furnace, and 4 is a watering cooler. Moreover, the solid line arrow in FIG. 1 represents the raw material of carbonaceous materials, such as subbituminous coal or lignite, and the flow of the manufactured carbonaceous material 1. On the other hand, a broken line arrow represents a gas flow generated by a pyrolysis process or the like.

  First, subbituminous coal or lignite as raw material is loaded into a hopper (not shown) and supplied to the screw conveyor 3a of the preheating furnace 3 through the first rotary valve 5a. The subbituminous coal or lignite charged into the preheating furnace 3 via the screw conveyor 3a is heated, for example, at 490 ° C. in the preheating furnace 3 to remove moisture.

The pretreated subbituminous coal or lignite is sent out from the preheating furnace 3 and then supplied to the screw conveyor 2a of the rotary kiln 2 through the second rotary valve 5b and charged into the rotary kiln 2. In the rotary kiln 2, pyrolysis is performed at 650 to 850 ° C. while stirring and moving the raw subbituminous coal or lignite at an arbitrary speed. Thereby, a part of volatile matter (VM: gas components such as hydrocarbons, CO, H ₂ ) and tar are released from subbituminous coal or lignite. On the other hand, the solid component remaining in the rotary kiln is referred to as char, and this becomes the carbon material of the embodiment of the present invention having the properties described later. After the char is delivered from within the rotary kiln 2, it is cooled by a watering cooler 4 and can be stored for use in a sintering furnace.

  Unlike a solid coke, the carbonaceous material (cheer) produced by thermal decomposition in the rotary kiln 2 is a powdered carbonaceous material. As is well known, coke is carbonized in a coke oven at 1100 to 1200 ° C., and coal particles are caking together to form a lump. In the case of the carbonaceous material of the present invention, Such caking property is not necessary, and any pyrolysis product in which a part of volatile matter and tar are removed from coal may be used.

  In the present embodiment, the pretreatment by the preheating furnace 3 is performed and then the rotary kiln 2 is charged to perform the thermal decomposition. However, the pretreatment may be omitted and the thermal decomposition may be performed. Further, the cooling method is not particularly limited, and an external cooling type rotary cooler may be used in addition to the watering cooler.

  Moreover, the gas (VM gas) produced | generated by thermal decomposition can be reused by supplying to gas utilization equipment from the inside of a furnace. Specifically, the gas generated by pyrolysis may be supplied to the rotary kiln 1 as fuel to pyrolyze subbituminous coal or lignite. Further, after the gas is combusted in the combustion furnace 6, the generated flue gas can be sent to the preheating furnace 2 and effectively used in the preheating process.

Thus, the carbonaceous material (char) of the embodiment of the present invention manufactured by pyrolyzing subbituminous coal or lignite at 650 to 850 ° C. has a volatile content (VM) of 1.0% or more, hydrogen and carbon. The atomic number ratio (H / C) is 0.040 or more, the 0.1 to 10 μm porosity measured by the mercury intrusion method is 50 mm ³ / g or more, and the reaction start temperature is 550 ° C. or less.

  That is, the carbonaceous material according to the embodiment of the present invention having a volatile content (VM) of 1.0% or more is easily cut in the chemical structure, and at a lower temperature when charged into a sintering furnace together with iron ore or the like. The reaction is started. Further, when the atomic ratio (H / C) is 0.040 or more, the structure contains many hydrogen atoms, the aromatic polycyclization is not sufficiently advanced, the chemical structure is easily cut off, and the temperature is low. The structure that starts the reaction is included.

Further, when the pore size measured by mercury porosimetry is 0.1 to 10 μm and the amount of pores is 50 mm ³ / g or more, the combustion start temperature is lower than when the value is smaller than 50 mm ³ / g, and the combustion rate is Since it becomes larger, the sintering reaction is further promoted. Note that pores having a pore size smaller than 0.1 μm are the factors that determine the flammability because the oxygen diffusion rate is relatively slow compared to the combustion rate under the reaction atmosphere conditions in the sintered layer. Must not. In addition, pores larger than 10 μm have a small effect on the flammability since the pore surface area is small. Therefore, in the carbonaceous material according to the embodiment of the present invention, the amount of pores having a pore diameter of 0.1 to 10 μm greatly affects the combustibility. Here, for easier understanding, FIG. 2 shows the pore volume distribution of Comparative Example A, which is a carbonaceous material and powder coke of Example H described later. As shown in FIG. 2, in Example H, there are much more pores having a pore diameter of 0.1 to 10 μm than in Comparative Example A.

  Carbonaceous materials having the above properties with respect to the volatile matter (VM), the atomic ratio (H / C), and the pore diameter measured by mercury porosimetry of 0.1 to 10 μm pore volume have a reaction start temperature. The reaction is started at a temperature lower than 550 ° C. and lower than the powder coke. Here, for easier understanding, the weight reduction curves of Example H and Comparative Example A are plotted in FIG. 3, and the first derivative of FIG. 3 is plotted on the vertical axis, and the relationship between temperature and reaction rate is shown. The expressed weight loss rate curve is shown. As shown in FIGS. 3 and 4, the carbonaceous material of Example H has a lower reaction start temperature than the coke boil of Comparative Example A, and is 550 ° C. or lower.

  Therefore, the solid fuel of the embodiment of the present invention made of the carbon material emits a gas (combustion gas) such as hydrocarbon at a temperature lower than that of the powder coke when ignited in the sintering machine. The combustion gas accelerates the temperature rise of the raw materials and fuel for sintering and promotes the sintering reaction in the combustion zone, improving the combustion efficiency, so that the unit consumption of the fuel for sintering can be reduced. In addition, the amount of carbon dioxide emitted during the production of sintered ore can be reduced as compared with the prior art. In addition, the sintered ore manufactured using the solid fuel according to the embodiment of the present invention made of the carbon material has higher strength than that manufactured using the powder coke, and thus the production rate of the sintered ore and The product yield can be improved.

  In addition, since the combustion efficiency is improved as described above, the amount of nitrogen oxide generated during combustion is reduced. This is presumably because the CO concentration around the carbonaceous material is relatively high due to good combustibility, and nitrogen oxides generated from the carbonaceous material are easily reduced. Therefore, by producing sintered ore using the carbonaceous material of the present embodiment, it is possible to reduce the amount of nitrogen oxide emissions during the production of sintered ore than before.

  For carbon materials with high volatile matter (VM), when used in a sintering machine, part of the volatile matter (VM) generated in the low temperature region is sucked into the dust collector and blower without contributing to combustion. More frequent maintenance of the dust collector or the like may be required, which requires labor and cost. For this reason, it is preferable that the carbonaceous material of embodiment of this invention is 10% or less of volatile matter (VM).

The carbonaceous material according to the embodiment of the present invention preferably has a maximum reaction rate temperature of 600 ° C. or lower and a reaction rate at 1000 ° C. of 0.19 min ⁻¹ or higher. By having the property, the sintering reaction can be further promoted, so that the production rate and product yield of the sintered ore can be further improved.

Furthermore, the carbonaceous material of the embodiment of the present invention preferably has a microstrength index (MSI _0.21 ) of 20 or more in addition to the above conditions. When it is 20 or more, the production rate and yield of the sintered ore are further improved. The reason why the production rate and the yield are further improved when the microstrength index is 20 or more is not clear, but the process of mixing and granulating the raw iron ore and adjusting the blended raw material In, the rate of exposure to the carbonaceous material of the embodiment of the present invention is increased on the surface of the granulated product as a blended raw material by reducing the rate at which the carbonaceous material of the embodiment of the present invention is broken and becomes a fine powder. This is probably because the ignitability of the granulated material is increased and the pulverization is suppressed, so that the number of particles that scatter and do not function as a fuel is reduced.

  Next, the production of sintered ore using the carbonaceous material of the present embodiment will be described by taking as an example the case of using a downward suction type dwyroid type sintering machine. FIG. 5 is a schematic view of a manufacturing process of sintered ore, 10 is a sintering machine, 11 (11a to 11d) is a hopper, and 12 (12a, 12b) is a drum mixer.

  First, the iron ore, which is a raw material of sintered ore, crushed and adjusted to a suitable particle size, auxiliaries such as limestone and serpentine, return ore, and the carbonaceous material and powder coke of this embodiment Solid fuel is loaded into the iron ore hopper 11a, the auxiliary material hopper 11b, the return hopper 11c, and the solid fuel hopper 11d. The iron ore, secondary raw material, return mineral, and solid fuel delivered from each hopper are loaded into the kneading drum mixer 12a at a predetermined ratio, crushed and kneaded, and then water is added in the granulating drum mixer 12b. To be pseudo-particles (granulated products). The pseudo particles are loaded into the surge hopper 13 and then cut out by the drum feeder 14 and are layered so as to have a predetermined thickness (for example, 500 to 700 mm) on the pallet 10a, which is the endless of the dwelloid type sintering machine 10. (Hereinafter, the layer in which the pseudo particles are laminated is referred to as a raw material layer 31).

  Next, the solid fuel in the granulated material (pseudoparticles) on the surface layer on the pallet 10a is ignited by the ignition furnace 15, and the sintering process is started. After ignition, the wind box 10b burns solid fuel and volatile matter released from the solid fuel while sucking air downward, and the quasi particles on the pallet 10a are sintered by the combustion heat to sinter. This is cake 40.

  FIG. 6 schematically shows the state of the sintering raw material in the sintering process, and the temperature at a certain point of the sintering raw material on the pallet 10b when the solid fuel of the present embodiment is used as the sintering fuel. This is an example of the distribution. In the ignition furnace 15, the carbonaceous material of the present embodiment above the raw material layer 31 is ignited and the combustion zone 32 is lowered downward, but in the dry zone 33 immediately below the combustion zone, the temperature of the raw material and fuel is increased by the combustion gas. . On the other hand, the temperature of the portion where the combustion has proceeded and ended is lowered to become a cooling zone 34. Referring to FIG. 5 in addition to FIG. 6, as the end point of the endless pallet 10a approaches, the combustion proceeds, the raw material layer 31 decreases and the cooling zone 34 increases to form the sintered cake 40. This is understood schematically. The temperature distribution shown in FIG. 6 is substantially the same behavior as in the conventional case where powder coke is used as a solid fuel.

  The sintered cake formed by the sintering process is sent out from the endless pallet 10 a, then crushed by the first crusher 16, and cooled by ventilation in the cooler 17. Subsequently, after being further crushed by the screen 18 and the second crusher 19, it is provided to a multistage sieve 20 to become a sintered ore having a predetermined particle size. On the other hand, the sintered ore that does not satisfy the predetermined particle size is returned to ore and reused as a sintering raw material.

  The gas generated by the sintering process is sent out from the wind box 10b and discharged from the exhaust cylinder 23 through the dust collector 21 and the fan 22.

  The carbonaceous material of the embodiment of the present invention can be used as at least part of the solid fuel loaded in the hopper. The mixing ratio of the carbonaceous material of the present embodiment in the solid fuel used for the production of sintered ore is not particularly limited, and it is also possible to use all the solid fuel as the carbonaceous material of the present embodiment. You may mix and use the carbonaceous material and powdered coke of embodiment.

  Examples of the present invention will be described below. Note that the present invention is not limited to the following conditions and the like as long as the object of the present invention is not impaired.

  From the raw materials shown in Table 1, the carbonaceous materials of Examples C to I were produced by thermal decomposition at 650 to 850 ° C. using a rotary kiln. About these, ratio of volatile matter (VM), atomic ratio of hydrogen and carbon (H / C), reaction start temperature, reaction rate maximum temperature, reaction rate at 1000 ° C., 0.1 to 10 μm pore by mercury intrusion method The quantity (measured using a mercury porosimeter) and the microintensity index were determined.

  That is, for the reaction start temperature, 10 mg of a sample having a particle size adjusted to 0.15 to 0.25 mm was put into a thermobalance, the temperature was raised at a rate of temperature rise of 10 ° C./min in an air atmosphere, and weight loss was measured. The temperature at which the weight loss rate at this time stably exceeded 0.002 (l / min) was defined as the reaction start temperature.

  For the maximum reaction rate temperature, a weight raw material curve as shown in FIG. 1 is prepared from the above-described measurement of weight loss, and the temperature at which the slope of the weight decrease curve is maximum (the weight loss per unit time is the maximum). Temperature) was defined as the maximum reaction rate temperature.

  As for the reaction rate at 1000 ° C., 10 mg of a sample whose particle size was adjusted to 0.15 to 0.25 mm was put in a thermobalance, the temperature was raised to 1000 ° C. in a nitrogen atmosphere, and then the atmosphere was an initial atmosphere. The weight reduction ratio per unit time (ratio of weight loss to initial weight) (1 / min) was determined by measuring.

  Moreover, the volatile matter (VM) was measured by the method described in JISM8812.

  In addition, the atomic ratio (H / C) of hydrogen and carbon is calculated based on the weight percentages C% and H% of carbon and hydrogen measured by elemental analysis. H / C = (H% / 1) / ( C% / 12).

  Moreover, the amount of pores having a pore diameter of 0.1 to 10 μm measured by mercury porosimetry was measured using a mercury porosimeter.

The micro-strength index (MSI _0.21 ) was measured by placing a 0.5-1.0 mm sample 2 g and 12 φ7.9 mm iron balls in a cylindrical container of φ24.2 × L300 mm and applying an impact of 800 revolutions at 25 rpm. After the addition, it was determined by sieving with a 70 mesh (0.21 mm) sieve and determining the weight percentage of the weight of +0.21 mm (0.21 mm or more) relative to the sample weight when the weight was measured.

  Furthermore, the production rate and product yield of sintered ore when using the carbonaceous materials of Examples C to I were evaluated by a sintering pot test.

  As a sintering pot test, using a sintering test apparatus having a diameter of 30 cm and a layer height of 60 cm, the prescribed raw materials of Australian iron ore: 53%, Brazilian iron ore: 30%, limestone: 14%, serpentine : The test which manufactures a sintered ore at 3% (all are the mass%) was implemented. First, the blended raw material was charged to a height of 60 cm in the sintering test apparatus, and then added to the surface carbon material of the raw material layer with a propane gas burner for 90 seconds. Thereafter, a sintering reaction was performed while suctioning air downward at a constant negative pressure of 15 kPa. The sintered body after a series of sintering treatments was sufficiently cooled, dropped from a height of 2 m four times and crushed, and a particle size of 5 mm or more was recovered as sintered ore. From this material balance, the production rate and yield of sintered ore were measured. Evaluation is based on production rate and product yield. Compared to the base conditions using coke breeze (carbon material A), △ is equivalent, ◯ is excellent, and ◎ is better. did. Further, NOx in the exhaust gas in the sintering pot test was also measured.

  These results are shown in Table 1. Further, as Comparative Example A, powder coke was used as the solid fuel, and the same measurements and evaluations as in Examples were performed. Furthermore, as Comparative Example B, a carbonaceous material was produced in the same manner as in the example using caking coal as the raw material for the carbonaceous material, and the same measurement and evaluation as in the example were performed.

As shown in Table 1, in Examples C to I each having a reaction start temperature of 550 ° C. or lower, the production rate is improved and the product yield is also improved as compared with the comparative example that is powder coke. In particular, Examples F to I in which the maximum reaction rate temperature is 600 ° C. or less and the reaction rate at 1000 ° C. is 0.19 min ⁻¹ or more further improve the production rate and product yield. Furthermore, Examples H and I satisfying the above conditions and having a microstrength index of 20 or more can further improve the production rate and the product yield. Further, the concentration of NOx in the exhaust gas can be reduced.

  According to the present invention, it is cheaper than the conventionally used sintering fuel, has excellent combustion efficiency, can improve the production rate of the sintered ore, and the yield of the product, and at the time of producing the sintered ore It is possible to provide a fuel for sintering iron ore that makes it possible to achieve a reduction in nitrogen oxide emissions.

Claims (9)

A carbonaceous material for use as a solid fuel for sintering iron ore and having the following properties.
(i) the reaction start temperature is 550 ° C. or lower,
(ii) Volatile content (VM) is 1.0% or more
(iii) The atomic ratio (H / C) of hydrogen to carbon is 0.040 or more,
(iv) The amount of pores having a pore diameter of 0.1 to 10 μm measured by the mercury intrusion method is 50 mm ³ / g or more The carbonaceous material according to claim 1, wherein the carbonaceous material further has the following properties.
(v) the maximum reaction rate temperature is 600 ° C. or less,
(vi) Reaction rate at 1000 ° C. is 0.19 min ⁻¹ or more The charcoal material according to claim 1 or 2, wherein the charcoal material further has the following properties.
(vii) Micro strength index (MSI _0.21 ) is 20 or more   The carbonaceous material according to claim 1 or 2, wherein the carbonaceous material is manufactured using subbituminous coal or lignite.   The carbonaceous material according to claim 3, wherein the carbonaceous material is manufactured using subbituminous coal or lignite.   A method for producing sintered ore, wherein the carbonaceous material according to claim 1 or 2 is used as a solid fuel.   A method for producing a sintered ore, wherein the carbonaceous material according to claim 3 is used as a solid fuel.   A method for producing a sintered ore, wherein the carbonaceous material according to claim 4 is used as a solid fuel.   A method for producing a sintered ore, characterized in that the carbonaceous material according to claim 5 is used as a solid fuel.

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