JP2006070294A - Method for producing sintered ore - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a sintered iron ore containing metallic iron which has good reducibility even when the content of a blast furnace slag forming component is small and has a high drop strength of 90% or more.
SOLUTION: A blended raw material composed of fine iron ore and other iron-based raw materials, auxiliary raw materials and carbonaceous materials is supplied to a sintering machine, and the carbonaceous materials are burned to melt at least a part of the iron-based raw materials. the method of manufacturing a sintered ore cooling and agglomerated of then was, compounding the raw material SiO ₂ content containing 3.6 mass% or less of the fine iron ore with the addition of carbonaceous material 10 mass% or more to the sintering machine A method for producing sintered ore to be supplied and sintered.
[Selection] Figure 1

Description

The present invention relates to a method for producing a sintered ore, and in particular, a method for advantageously producing a sintered ore exhibiting high strength characteristics even though the content of SiO ₂ and CaO as blast furnace slag forming components is small. suggest.

In recent years, the iron-based raw material charged in the blast furnace has been increasingly dependent on sintered ore due to the lack of high-quality massive iron ore. In general, the sintered ore is not only powdered iron ore, but also iron-based raw materials such as returned ore, sulfated iron, sand iron, scale, blast furnace dust and converter dust, limestone as a slagging material, heat source for firing It is manufactured by sintering mainly powdery blended raw materials obtained by mixing carbonaceous materials and the like. That is, an appropriate amount of water is added to the blended raw material, mixed, granulated, charged onto a sinter pallet, and the carbonaceous material is burned while circulating air downwards. At least a part is melted and then cooled, solidified, and crushed. In other words, sintered ore is an artificial ore in which iron-based raw materials such as powdered iron ore react with a slag component such as CaO or SiO ₂ used as a flux and at least partly melts and agglomerates. It can be said.

The sintered ore used in the blast furnace usually has a higher content of SiO ₂ and CaO than the massive iron ore. Therefore, as the blending ratio of the sintered ore in the iron-based raw material charged into the blast furnace increases, the amount of blast furnace slag generated increases, resulting in an increase in the fuel ratio of the blast furnace and the processing cost of the blast furnace slag. The problem arises. Moreover, recently, from the viewpoint of resource saving and energy saving, there is an increasing demand for reduction in the fuel ratio and slag ratio of the blast furnace.

On the other hand, reducing the SiO ₂ and CaO contents in the sintered ore leads to a decrease in the strength of the sintered ore. Therefore, the lower limit value of the SiO ₂ content is currently about 4.5 mass%, CaO The lower limit of the content is suppressed to about 9.O mss%. For example, a manufacturing method (see Patent Document 1) low slag sinter of CaO is 6～9Mass%, of SiO ₂ is less than or equal to the average 5 mass%, the production method of the sintered ore of CaO / SiO ₂ is 1.90 to 2.10 (JP Reference 2), a method for producing sintered ore with 4.2 to 4.9 mass% of SiO ₂ , 1.5 to 3.O mass% of MgO and 1.8 to 2.2 of CaO / SiO ₂ (see Patent Document 3), or SiO ₂ There 4.6 mass% or less, CaO / SiO ₂ is 1.0 to 3.0, MgO is like 0.5 mass% greater than the production method of the sintered ore (refer to Patent Document 4) have been proposed.

However, in any of these conventional technologies, the drop strength (shutter strength: SI) is reduced to about 85% as the SiO ₂ and CaO contents decrease, and the SiO ₂ content in the sintered ore is 4.5%. About 5.5 mass%, CaO content is currently at the lower limit of about 9.O mass%. Incidentally, the SiO ₂ content of 4.5 to 5.5 mass% or more, the current sintered ore containing CaO or 9.O mass%, the drop strength (SI) is set to about 89%. In addition, there is an idea to secure the necessary strength by increasing the carbonaceous material content in the blended raw material against the decrease of so-called flux components such as SiO ₂ and CaO to be contained. There is a problem that the microstructure of the ore becomes a large number of crystals derived from the olivine-based melt formed at the time of melting, and the reducibility (RI) of the sintered ore is deteriorated.
Japanese Patent Laid-Open No. 10-273738 Japanese Patent Laid-Open No. 11-80845 Hokkei 11-131151 Japanese Unexamined Patent Publication No. 2000-178659

The object of the present invention is to establish a technique capable of overcoming the above-mentioned problems of the prior art, that is, 90% even if the content of components (SiO ₂ , CaO, etc.) forming the blast furnace slag is less than that of the prior art. An object of the present invention is to propose an advantageous method for producing a sintered ore that can exhibit the above-described drop strength (SI) and that can obtain a metal iron-containing sintered ore having high reducibility characteristics.

The inventors have arrived at the present invention according to the gist configuration described below during research aimed at realizing the above object.
That is, the present invention supplies a blended raw material consisting of fine iron ore and other iron-based raw materials, auxiliary raw materials, and carbonaceous materials to a sintering machine, and burns the carbonaceous materials to at least part of the iron-based raw materials. the method of manufacturing a sintered ore cooling and agglomerated of mixture was allowed to melt, the formulation in the raw material SiO ₂ content containing 3.6 mass% or less of the fine iron ore with the addition of carbonaceous material 10 mass% or more sintering This is a method for producing a sintered ore, characterized in that it is supplied to a machine and sintered.

The present invention also provides a compounding raw material comprising powdered iron ore and other iron-based raw materials, auxiliary raw materials, and carbonaceous materials to a sintering machine and combusting the carbonaceous materials to at least part of the iron-based raw materials. In the method for producing sintered ore which is melted and then cooled and agglomerated, first, a blended raw material containing fine iron ore containing 10% by mass or more of carbonaceous material and 3.6% by mass or less of SiO ₂ and some pressurized Zhuang molded into a molded article to be obtained, along with containing carbonaceous material 10 mass% or less, and granulating the blended raw materials SiO ₂ content contains fine iron ore of more than 3.6 mass% to obtain the A method for producing a sintered ore, characterized in that a mixture comprising a granulated product is supplied to a sintering machine and sintered.

In the present invention, said the SiO ₂ content in the mixed material containing fine iron ore is 3.6 mass% or less, containing 6 mass% or less of CaO, and is obtained by pressure forming in briquette machine, The granulated product is granulated with a drum mixer.

In the present invention, the SiO ₂ content in the mixed material containing fine iron ore is 3.6 mass% or less, those obtained by adding the carbonaceous material 10 mass% or more is supplied to the sintering machine and sintered Based on the above, it is based on the proposal of the technique which manufactures high strength metallic iron containing sintered ore. As a background to the development of this technology, fine iron ore with a SiO ₂ content of 3.6 mass% or less is a compounding raw material that makes it difficult to produce high-strength sintered ore as described above. However, there is a strong demand for the development of a technique for producing a high-strength sintered ore using such a powdered iron ore.

In view of this, the inventors first considered using 3.6% by mass or less of a fine iron ore with a low SiO ₂ content and another fine iron ore with a high SiO ₂ content. Moreover, it was found that, for example, it is desirable to use a compact obtained by separately press-molding as the fine iron ore having a SiO ₂ content of 3.6 mass% or less. For example, in a granulated product such as a drum mixer, the SiO ₂ content once granulated is 3.6 mass% or less at the time of mixing with other powdered iron ore when combined with other powdered iron ore. This is because the pseudo particles made of fine iron ore collapse and mix with other fine iron ores. Therefore, in the present invention, carbonaceous material content of 10 mass% or more, CaO content is less 6 mass%, and, when the SiO ₂ content of the mixed material containing 3.6 mass% or less of the fine iron ore, sintered Preferably, the blended raw material is once pressure-molded with a briquette machine to form a compact, and this compact is supplied to the sintering machine as a mixture of other blended raw materials such as simple iron ore or granulated material. To do.

According to the present invention, it is possible to obtain a sintered ore having high strength and good reducibility even when powdered iron ore having a SiO ₂ content of 3.6 mass% or less is used as a blending raw material for charging into a sintering machine. it can. In particular, sintered materials containing powdered iron ore containing 10 mass% or more of carbonaceous material and 3.6 mass% or less of SiO ₂ are metallic iron such as metallic iron, wustite and magnetite. Since the system melt can be generated, a sintered ore with high strength, high reducibility, and a portion of metallic iron remaining can be obtained.

Furthermore, a part of the blended raw material containing 10% by mass or more of carbonaceous material and powdered iron ore containing 3.6% by mass or less of SiO ₂ is formed into a compact, and the remaining blended raw material is a granulated product. When the mixture raw material in the state of a mixture of these compacts and granulated materials is placed on a sintering machine pallet and sintered, the resulting sintered ore is The amount of SiO ₂ is lower than that of the conventional one, that is, SiO ₂ is 4.0 to 5.0 mass%, CaO is 7 to 9 mass%, high strength and high reducibility, and part of metal iron remains stably. It can be set as the sintered ore of the state.

  As described above, according to the present invention, even if the content of the blast furnace slag forming component is smaller than that of the conventional one, the high-strength metallic iron-containing fired metal having high reducibility and exhibiting a drop strength (SI) value of 90% or more. The ore can be produced easily.

  In general, as one method for reducing the fuel ratio of a blast furnace, there is a concept of using metallic iron as a raw material for charging a blast furnace. Therefore, it is considered that if the metallic iron is contained in the sintered ore in advance, the same effect as described above, that is, effectively acts for reducing the blast furnace fuel ratio. However, the actual condition is that ordinary sintered ore contains almost no metallic iron. The reason for this is that the iron source in the blended raw material is temporarily reduced by the reducing atmosphere due to the action of the carbonaceous material, etc. to produce metallic iron, but is re-oxidized in the high-temperature oxidizing atmosphere after the sintering reaction is completed. Because it will end up.

Hereinafter, the best embodiment of the present invention will be described together with the motivation for developing the present invention.
The sintered ore is obtained by reacting and melting powder iron ore with a flux (that is, slag components such as CaO and SiO ₂ ) and then agglomerating by cooling. Therefore, it is well known that various factors such as the particle size and blending ratio (basicity) of the blended raw material influence the strength of the sintered ore. In particular, SiO ₂ content is 4.0~5.O mass%, the sinter of CaO content low slag system about 7 to 10 mass%, with a decrease of the flux components such as CaO and SiO _2, fusion It is known that the drop strength (SI) of the product sinter decreases due to the lack of liquid volume.

Therefore, the inventors have made various studies on the product sintered ore having the characteristics that the melt generation amount does not depend on the added flux component amount. As a result,
(1) When using powdered iron ore with a SiO ₂ content of 3.6 mass% or less as the blended raw material, is this powdered iron ore charged into the sintering machine as a blended raw material premixed with carbonaceous materials? ,
(2) In a blended raw material, a powdered iron ore having a SiO ₂ content of 3.6 mass% or less and a carbonaceous material are mixed in advance and then formed into a compact by molding and the remaining blended raw materials, for example, After preparing coke powder etc. and granulating it to prepare a granulated product, these compacts and granulated product are mixed together, and the blended raw material consisting of this mixture is loaded into a sintering machine. Or as a raw material
When the sintered ore was produced by this method, it was found that a highly reducible and high-strength metallic iron-containing sintered body was obtained, and the present invention was completed.

Incidentally, in a general sinter ore, in a reducing atmosphere at the time of the carbonaceous material burned to generate many olivine melt derived from Fe2O3 and SiO _2, comprising a microstructure resulting from this melt sinter Is known to have low reducibility.
On the other hand, in the production of sintered ore, when using an ore containing 3.6 mass% or less of SiO ₂ and using as a blending raw material containing 10 mass% or more of carbonaceous material, It was found that the amount produced was reduced, the microstructure derived from the wustite melt was increased, the residual metal iron was observed, and as a result, a sintered body having both high strength and high reducibility was obtained. Furthermore, when an ore containing 3.6 mass% or less of SiO ₂ is used as a compounded raw material as a molded product obtained by pressure molding a carbonaceous material containing 10 mass% or more, the molded product becomes It becomes denser and increases the internal pressure of the molded body accompanying the gasification of the carbonaceous material, strengthens the reducing atmosphere, and acts to suppress the invasion of oxidizing gas. As a result, it can be seen that a large amount of metallic iron remains in the sintered ore (on the compact side), resulting in both high strength and high reducibility characteristics and a sintered iron containing metallic iron. It was.

Next, in order to obtain a sintered ore having the above-described desired characteristics, the inventors have added an amount of carbonaceous material added to fine iron ore containing 3.6 mass% or less of SiO ₂ in the blended raw material, particularly this amount. The suitable range of the carbonaceous material addition amount in the said molded object shape | molded using the ore was examined. As a result, when the amount of carbonaceous material added to the compact was less than 10 mass%, metallic iron could not be obtained, so 10 mass% was set as the lower limit. On the other hand, if this carbonaceous material addition amount is 10 mass% or more, a sintered ore having both high strength and high reducibility characteristics due to the presence of metallic iron and an increase in the microstructure derived from the wustite melt. It turns out that it is obtained. The upper limit of the carbon material addition amount is not particularly required, but may be determined according to manufacturing requirements, economics, and the like, and is preferably about 25 mass%, for example, 10 to 20 mass%. It is more preferable.

Further, in the present invention, when using fine iron ore having a SiO ₂ content of 3.6 mass% or less as a part of the blended raw material, in addition to the carbonaceous material, a CaO-containing auxiliary raw material (for example, limestone or calcined lime) It is preferable that the addition amount of CaO is previously stopped at a relatively small amount of 6 mass% or less. The reason is that if the CaO content in the compact is 6 mass% or less, the strength and reducibility of the sintered ore will not be reduced so much. Use as a molded body to be molded by pressurization can be performed without adding a CaO-containing auxiliary material.
In addition, when using the fine iron ore whose content of SiO ₂ is 3.6 mass% or less as a part of the mixed raw material, the remaining mixed raw material uses fine iron ore with a content of SiO ₂ exceeding 3.6 mass%. Carbonaceous material is added to 10 mass% or less of this iron ore with SiO ₂ > 3.6 mass%. In this case, the reason for setting the amount of the carbon material to 10 mass% or less is that if it exceeds 10 mass%, the amount of olivine-based melt produced becomes excessive, the reducibility is reduced, and the aeration of sintering is also deteriorated. This is because productivity decreases.
Then, those granulated with Doramukikisa for carbonaceous material containing powder ore of the remainder _{(SiO 2> 3.6 mass%)} , it is preferable to use as part of the mixed material. The reason is that it is not necessary to briquette this part, and a normal granulation method can be applied.

Next, an example of a preferable method for producing a sintered ore according to the present invention will be described with reference to FIG.
First, to determine the raw material formulation for the production of sintered ore in the SiO ₂ content of 4.0 to 5.0 mass%.
That is, the reference, SiO ₂ content based on the amount of fine iron ore is not more than 3.60 mass%, this and seek other fine iron ore amount used in mixture, SiO ₂ content of the entire mixed material The formulation is designed to be 4.0-5.0 mass%. Conversely, the other compounding ingredients other than fine iron ore content of SiO ₂ is 3.60 mass% or less, for example, a fine iron ore content of SiO ₂ is 3.6 mass% than the formulation ingredients together with carbonaceous material as a reference, SiO ₂ content of the entire mixed material is such that 4.0 to 5.0 mass%, may determine the amount of fine iron ore SiO ₂ content is 3.60 mass% or less.

Subsequently, the CaO addition amount and the carbonaceous material addition amount with respect to the fine iron ore whose content of SiO ₂ is 3.60 mass% or less are determined, and these are mixed. Similarly, the SiO ₂ content of other formulation materials other than fine iron ore is 3.60 mass% or less, for example fine iron ore content of SiO ₂ exceeds 3.6 mass%, CaO addition amount, addition carbonaceous material Determine the amount.

The SiO ₂ content of 3.60 mass% or less of the fine iron ore, CaO to this, determining the respective amount of carbonaceous material, after mixing, water was added and molded under pressure to the molded body. The molded body only needs to have a shape capable of maintaining the shape formed when charged on a sintering machine, and water, bentonite, molasses, or the like may be used as a binder.

On the other hand, other raw materials other than fine iron ore with a SiO ₂ content of 3.60 mass% or less, such as fine iron ore with more than 3.6 mass% of SiO ₂ , are mixed and granulated (typically Use a drum mixer) to make a granulated product. To this granulated product, CaO, charcoal, and further SiO ₂ raw material were added if necessary, charged from the entrance side of the drum mixer, granulated by a rolling method and granulated, and thus obtained. The granulated product is supplied to the compact, preferably to the sintering machine together with the above two types. In the process of supplying to the sintering machine, both blended raw materials (molded product, granulated product) are mixed in advance, and the two raw materials are mixed and charged on the sintering machine pallet and then sintered. .

  In the mixing operation, a mixing drum mixer is used, and both raw materials are once passed through the drum mixer to achieve uniform mixing, or the molded product is granulated with other blended raw materials (granulated product mixture). A method of adding to the drum mixer, or a method of mixing the molded body and the granulated material when discharged on the same belt conveyor and stored in a sintering machine hopper may be used.

  Hereinafter, while manufacturing the sintered ore manufacturing method concerning this invention is demonstrated concretely based on an Example, the example which remove | deviates from the requirements of this invention was compared, and each effect was compared. In manufacturing, nine brands of fine iron ore were used, and these were set as the ore blending ratios shown in Table 1. Table 2 shows a breakdown of the main raw materials and auxiliary raw materials.

Example 1
In this example, when adjusting the blending raw material, the silica was added so that the SiO ₂ content in the sintered ore was 4.O mass%, and the CaO content in the sintered ore was 7.O mass. Limestone was blended so as to be%. Also, the return ore was blended so as to be 20 mass% with respect to the new raw material (main raw material and auxiliary raw material).

And in manufacturing,
(1) First, the ores A, B, D, and G are mixed after adding so that the carbonaceous material (powder coke) content is 10 mass%. A compact was obtained by pressure molding.
In this pressure molding treatment, bentonite and molasses were added as needed for those with insufficient molded body strength. The molded body was formed into a particle size having a volume of 10 cc as an almond-like shape. Therefore, among the ore brands in Table 1, those other than the above are the remaining blended raw materials that are not pressure-molded, and are to be formed into so-called granules.
(2) Next, the remaining blended raw materials (C, E, F, H, I, the amount of which can be determined in advance by blending design) are put into a drum mixer, and auxiliary raw materials and moisture are added. While mixing and granulating, a granulated product was obtained.
(3) Next, the molded product (63 mass%) obtained in (1) is charged into the drum mixer in which the granulated product is accommodated, and the granulated product (37 mass%) and Mix well.
The total amount of carbon in the blended mixture was 7.O mass% with respect to the new raw material. Next, these manufacturing conditions are organized and shown in Table 3.

Next, the mixture consisting of the compact and the granulated product pretreated as described above was placed on a pallet of a sintering machine and subjected to a sintering operation according to a conventional method under air suction. Table 4 shows the quality of the obtained sintered ore. The evaluation of sintered ore is to obtain the metallic iron content by ordinary chemical analysis, to determine the drop strength (shutter index (SI)) by the method specified in Japanese Industrial Standard JIS M8711, and to be specified in Japanese Industrial Standard JIS M8713. The reducibility index (RI) was obtained by the method described above. The obtained sinter has a SiO ₂ content of 4.O mass%, a CaO content of 7.O mass%, stably contains metallic iron of about 8.2 mass%, SI is 92, and RI is A sintered ore with high strength and good reducibility was obtained.

(Example 2)
When the powdered iron ore of ore brands A, B, D, and G, the carbonaceous material and the auxiliary raw material containing CaO are mixed to obtain the molded body, the added amount of CaO in the molded body is 6 mass%. In addition to adding limestone and blending so that the carbonaceous material content is 10 mass%, mixing these, adding moisture and pressing with a briquette machine to obtain a molded body This was carried out in the same manner as in Example 1. The obtained sinter has a SiO ₂ content of 4.O mass%, a CaO content of 7.0 mass%, a metal iron content of 6.6 mass%, an SI of 93, and an RI of 66 with high strength. A sintered ore with good reducibility was obtained.

(Example 3)
Carbonaceous materials were added to ores A, B, D, and G so as to be 12 mass%, and after mixing these, moisture was added and pressure-molded with a briquette machine to obtain a compact. The total amount of blended charcoal was carried out in the same manner as in Example 1 except that the amount was 8.0 mass% with respect to the new raw material. The obtained sinter has a SiO ₂ content of 4.O mass%, a CaO content of 7.O mass%, a metal iron content of 11.2 mass%, an SI of 93, and a RI of 68. A sintered ore with good reducibility was obtained.

Example 4
SiO ₂ content of finished product sintered ore is blended with silica so that 5.O mass%, also except for blending the limestone as CaO content of sintered ore is 10.0 mass%, performed This was carried out in the same manner as in Example 1. The obtained sinter has an SiO ₂ content of 5.O mass%, a CaO content of 10.O mass%, a metal iron content of 7.5 mass%, an SI of 94, and an RI of 64. A sintered ore with high strength and good reducibility was obtained.

(Comparative Example 1)
Silica stone was blended so that the SiO ₂ content of the sintered ore was 4.O mass%, and limestone was blended so that the CaO content of the product sintered ore was 7.O mass%. Further, the return ore was blended so as to be 20 mass% with respect to the new raw material.
All raw materials were put together in a drum mixer and mixed and granulated while adding moisture. The total amount of coal in the blended raw material was 7.O mass% with respect to the new raw material. These manufacturing conditions are organized and shown in Table 5. Table 6 shows the quality of the sintered ore obtained after charging the above blend into a sintering machine. The sintered ore obtained here had a SiO ₂ content of 4.O mass% and a CaO content of 7.O mass%, but contained almost no metallic iron, so SI was 77, The RI was 69 and it became a sintered ore with low drop strength.

(Comparative Example 2)
Pre-mixed ore grades C, E, F, H, and I powdered iron ore is blended so that it becomes 10 mass% as a carbonaceous material, and after mixing these, water is added and mixed and granulated. did. That is, it was carried out in the same manner as in Example 1 except that all the blended raw materials were pressure-molded with a briquette machine. The obtained sintered ore has a SiO ₂ content of 4.O mass%, a CaO content of 7.O mass%, and almost no metallic iron, so that SI is 86 and RI is 50. It became a sintered ore with low strength and poor reducibility.

(Comparative Example 3)
In addition to blending ore brands A, B, D, and G powdered iron ore, carbonaceous materials and CaO containing auxiliary materials so that the amount of CaO added to the molded product is 7 mass%, the carbonaceous material is 10 mass. After blending so as to be%, water was added and mixing and granulation were carried out. That is, it was carried out by the same method as in Example 1 except that it was formed by a briquette machine. Although the obtained sintered ore had a SiO ₂ content of 4.O mass% and a CaO content of 7.O mass%, there was a portion containing about 5 mass% of metallic iron. However, the strength of the sinter was slightly low and the reducibility was poor.

(Comparative Example 4)
Carbonaceous materials were blended in advance to 4 mass% with respect to ore brands A, B, D, and G, and after mixing these, water was added and mixed and granulated. That is, it was carried out in the same manner as in Example 1 except that it was pressure molded by a briquette machine. The obtained sintered ore had a SiO ₂ content of 4.O mass% and a CaO content of 7.O mass%, but the one containing almost no metallic iron (0.1 mass%) No. 87, RI was 65, low in strength and poor reducibility.

(Comparative Example 5)
Except that silica stone is blended so that the SiO ₂ content of sintered ore is 5.O mass%, and limestone is blended so that the CaO content of the product sintered ore is 10.O mass%. The same method as in Comparative Example 1 was performed. The obtained sintered ore had a SiO ₂ content of 5.O mass% and a CaO content of 10.O mass%. 89, RI was 64 and the strength was low and the reducibility was poor.

  The technique according to the present invention is not only useful as a technique for producing sintered ore that is a raw material for blast furnace charging, but can also be used as a technique for producing reduced iron or sponge iron raw material.

It is a flowchart explaining the process example of the manufacturing method of the sintered ore which concerns on this invention.

Claims (4)

Supply blended raw material consisting of fine iron ore and other iron-based raw materials, auxiliary raw materials and carbonaceous materials to a sintering machine, burn the carbonaceous materials to melt at least a part of the iron-based raw materials, and then cool. In the method for producing the agglomerated sintered ore,
Compounding the raw material SiO ₂ content containing 3.6 mass% or less of the fine iron ore with the addition of carbonaceous material 10 mass% or more is supplied to the sintering machine, the production of sintered ore, which comprises sintering Method. Supply blended raw material consisting of fine iron ore and other iron-based raw materials, auxiliary raw materials and carbonaceous materials to a sintering machine, burn the carbonaceous materials to melt at least a part of the iron-based raw materials, and then cool. In the method for producing the agglomerated sintered ore,
First, a carbonaceous material as well as containing more than 10 mass%, a molded product obtained by vulcanizing Sho forming part of the formulation ingredients SiO ₂ content contains fine iron ore is 3.6 mass% or less, the carbonaceous material A mixture consisting of a granulated product obtained by granulating a blended raw material containing 10% by mass or less of SiO ₂ and more than 3.6% by mass of powdered iron ore is supplied to a sintering machine and sintered. A method for producing a sintered ore, characterized by comprising: Wherein the SiO ₂ content in the mixed material containing fine iron ore is 3.6 mass% or less, the method of producing sintered ore according to claim 1 or 2, characterized in that it contains 6 mass% or less of CaO . The method for producing a sintered ore according to claim 2, wherein the formed body is formed by pressure forming with a briquette machine, and the granulated material is formed by granulation with a drum mixer.

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