JPH05263155A - Production of sintered or pelletized ore as blast-furnace material using lime cake - Google Patents

Abstract

PURPOSE:To effectively utilize a lime cake discarded in the sugar manufactory in sintering or pelletizing a blast-furnace material in making iron. CONSTITUTION:Up to 100 pts.wt. of water is added to 1 pts.wt. of a lime cake to obtain a lime cake slurry. The slurry is added by <=10wt.% to the blast- furnace material to be sintered or pelletized and the blast-furnace material is kneaded to lump or pelletized. The lump or green pellet is calcined at <=about 1400 deg.C and then cooled. Consequently, calcium oxide combines with quartz sand in the course of sintering to form a low-viscosity slag, and the reducibility is improved. Meanwhile, a sintered article having a relatively uniform grain size capable of improving the ventilation of the charge bed in blast-furnace operation is obtained. Since molasses are also contained in the lime cake, the lime cake functions as a binder to lump powder ore, and a caking agent need not be added.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a sinter or pellet ore using a lime cake as a blast furnace raw material. The present invention relates to a method for producing a blast furnace raw material that enables to use lime cake discharged as industrial waste from a sugar factory in place of limestone used when producing mine.

[0002]

2. Description of the Related Art Iron and steel products are roughly classified into a pig iron production process for producing pig iron from iron ore, a steel production process for producing steel from hot metal or scrap, a rolling process and a surface treatment process for producing products from billets. Is manufactured through. For iron making equipment,
Blast furnace for smelting pig iron, sinter machine for producing raw ore sinter for charging into blast furnace, coke oven for producing reducing coke,
Further, a raw material processing device for compounding / crushing is provided. The sintering machine is an apparatus that sinters a mixture of powdered ore and other raw materials, and a coke oven mixes various coals and dry-distills at high temperature to produce coke. Then, iron ore, sintered ore, limestone, coke, etc. are charged into the blast furnace, and in a state where the ore and coke form a layer, the iron ore is reduced by the CO gas generated by the combustion of the coke, and pig iron is melted. It is supposed to do. By the way, the pig iron raw material must be one capable of economically producing hot metal. Therefore, it is preferable that the iron ore be of good quality, but generally, the iron ore is accompanied by various impurities. Moreover, in recent years, it has become difficult to obtain high-quality ores as the amount of steel production increases. However, even if it is a low-grade ore, if it is used in a blast furnace, if it is subjected to some treatment to separate and remove impurities and change the physical and chemical properties to carry out pretreatment to facilitate refining It can be used as a raw material. On the other hand, if the iron ore charged into the blast furnace is often in the form of powder, ventilation in the furnace is impaired and a non-uniform distribution is exhibited. In extreme cases, it causes bridges and slips, which hinders the operation. Therefore, it is necessary to make the iron ore finer as much as possible within the range where the ventilation is not impaired, improve the reducibility and improve the indirect reduction rate. That is, if the particle size is appropriately reduced, the surface area is increased, and it is possible to easily receive indirect reduction.

Iron ore mined from a mine is generally crushed to about 200 mm to 250 mm at the base of a mountain, but is sent to a steel mill with various sizes from large lumps to fine powder mixed. To use this as a blast furnace raw material,
It must be crushed to an appropriate size, sieved to a fine ore and, if necessary, agglomerated to give the most convenient condition for use. Iron ore, which has been crushed and sized to 10 mm to 50 mm, is directly charged into the blast furnace, while powder ore of 10 mm or less is generally used as a sintering raw material. Sintered ore is an excellent material for blast furnace charging because it can remove harmful components such as sulfur in the raw material during the sintering process. Widely adopted. Sintered ore should be agglomerated from iron ore powder such as dust or scale powder, scale powder, sulfuric acid slag, etc. generated in the process of crushing and screening mined iron ore and desulfurization roasting. Was the original purpose. However, the sizing process of the blast furnace charge for the purpose of improving the efficiency of the blast furnace causes a large amount of fine ore in the steel plant, and contributes to the process and the treatment of gas ash containing carbon and iron that is recovered together with the blast furnace gas. The need for firing has increased even further. Furthermore, improving the chemical and physical properties of the raw materials to increase the productivity of the blast furnace,
In order to reduce the fuel consumption, the pretreatment of the charged raw material was necessary, which was also one of the factors that greatly promoted the development.

Further enhancing the evaluation of sinter is the appearance of self-fluxing sinter, which replaces the previously used acid sinter (SiO ₂ ). This is also called lime sinter, and generally has a basicity (CaO / SiO ₂ ) of 1.20 or more. To this, a part or all of the solvent medium charged into the blast furnace is added in the sintering step, and limestone powder (CaO) is previously baked into the sintered ore. Compared to other raw materials, this self-fluxing sinter is artificially adjusted in composition and particle size, has excellent reducibility, and has excellent softening and melting characteristics in the blast furnace. There are advantages. As mentioned above, the increase of the undersize powder generated by the crushing and sieving of iron ore and the use of low grade ore for the agglomeration treatment of these powder ores will increase the supply of powder ore. ing. At the time of sintering these, if limestone is added as described above, the thermo-economic efficiency of the ore is improved, and at the same time, it can greatly contribute to the stability of the furnace condition in the blast furnace operation, so powdered ore is indispensable as a blast furnace raw material. It is becoming a thing.
That is, when limestone powder is mixed in the sintering raw material, the hard-to-reduce ferrite is reduced and the reducibility of the sintered ore itself is significantly improved. For the above reasons, the use ratio of lime sinter is increasing every year, but with the increase, the coke ratio gradually decreases. Therefore, at present, agglomeration processing of powdered ore,
Sintering methods that enable mass production of sinter with excellent quality have come into widespread use, and are now the method of manufacturing high-grade artificial raw materials.

The sinter ore is required to have appropriate grain size, strength and reducibility, and it is also desired that it has high drop strength and high pressure resistance. As the sintering raw material, mainly the blended ore, powdered ore and other selected powder such as limonite containing sulfur and arsenic that can be removed by sintering, sulfuric acid ore, sand iron, serpentine, blast furnace dust, open hearth slag, coke and It is also used in addition to return ore, mill scale and Dalai powder generated in the processing process. In the production of the self-fluxing sinter described above, powdered limestone having a size of 3 mm or less is mixed in the sintering raw material, and 5% to 12% of the limestone is added, whereby calcium oxide and silica sand are added in the sintering process. And form a slag with low viscosity and improve the reducibility of the sinter.
Further, in the operation, the air permeability of the charging layer is also improved and the production amount is increased, so that a product having a relatively uniform particle size can be obtained. As a sintering machine for agglomerating the powdered ore for the production of such a self-fluxing sinter, a Dwightroid type sintering machine, a Grinwald type sintering machine and an A.S. I. A B-type sintering machine and the like can be mentioned, but most of them actually operating are of the Dwightroid type. As described above, various binders (binders) are added to the sintering raw material as a measure to reduce the size of the sintering raw material and to improve productivity in the sintering process. There is also a method to use.
In this quick lime addition method, by substituting a portion of limestone in the sintering raw material with quick lime powder, the fact that the fine sintering raw material adheres around the core particles to form pseudo particles, is used in the sintering operation. The purpose is to improve the air permeability of the sintered pellets and improve the productivity. Addition amount of quicklime 1%
The productivity has been improved by as much as 5% to 8%, and the strength has been confirmed to be improved in terms of quality as well, but it is effective in reducing NOx in exhaust gas and is attracting attention.

Since the rich ore tends to be depleted as the production of iron and steel increases, the sinter ore as described above is largely in the spotlight as a poor ore treatment method. There is also a briquette method. These are based on the difference in the particle size of the raw materials used, and the pellet method is preferably finer than the briquette method. The raw material used to make the pellets is very fine and the sintering method is 8 mm
Is significantly different from using raw materials composed of 0.1 to 0.1 mm. Among the agglomeration mechanism of pellets, when basic gangue is present in the raw material and in self-fluxing pellets containing limestone, slag and calcium ferrite similar to sinter ore function as a binder, Are joined together. The pellet manufacturing process is roughly divided into three processes: a crushing process, a spheroidizing process for manufacturing raw pellets, and a firing process. In the pulverizing step, the raw material is pulverized into the extremely small particle size described above by a rod mill, a ball mill, or a combination thereof. When making self-dissolving pellets, finely crushed limestone is added to make blended raw materials. In the spheroidizing process, 8% to 10% in the blended raw material
Water is added and pelletized with a pelletizer such as a boring drum or a boring disk to form spherical raw pellets. Bentonite, so that it can withstand the impacts, etc. received when the raw pellets are transported to the firing process,
About 0.5% of binder such as lime is added. The firing process is the process of firing the raw pellets at 1,200 ° C.
It is heated and baked at a high temperature of 1 to 1,300 ° C. After that, it is cooled and becomes a product pellet with sufficient strength to withstand the drop impact and pressure during transportation and in the blast furnace.

The briquette method described above is a method of agglomerating the powder ore in which an appropriate amount of water or a binder is added and mixed, and the mixture is pressure-molded, and then the powder ore is cured by standing or heating and firing. It is suitable for small-scale powder agglomeration. The pressure molding in the briquette method is performed by a briquetting machine, but it is classified into a method of not heating after molding and a method of heating after molding depending on the difference in treatment method after molding. It should be noted that, as the lump making machine, there are an impeller type lump making machine and a compression type molding machine. The binder is extremely important when hardening the briquettes without heating and firing. As the binder, clinker dust, bentonite, lime, slaked lime, Portland cement, calcium chloride, magnesium chloride, silica sand, dregs powder, etc. may be used alone or in combination. In addition, organic substances such as pitch, molasses, pine resin, and cellulose may be used.

[0008]

As can be seen from the above-mentioned details, limestone that has been sized to 30 mm to 15 mm is directly charged into the blast furnace. Finer particles of limestone are powders as raw material for the blast furnace. It is used for the production of sinter or pellet ore in various pretreatments of ores and is essential as a binder in iron ores. Then, by adding limestone, a slag having a low melting point can be produced, and a desulfurization action can be performed. This limestone is a sedimentary rock whose main component is calcium carbonate (CaCO ₃ ), and is mainly collected as calcite. By the way, limestone is abundant in Japan, but it is not always guaranteed to be stable. On the other hand, using a large amount of lime is
There is a sugar industry in addition to the steelmaking field. Above all, in sugar mills that produce beet sugar, shredded beet (sugar radish)
The sugar is extracted as exudate from the exudation tower, and lime milk is added to it, which is then contacted with carbon dioxide to saturate the carbon dioxide. That is, when producing beet sugar, an extraction process, a cleaning process, a concentration process, and a crystallization process are performed, and limestone is used in the cleaning process. The crude sugar juice that has been exuded in the exudation tower contains colloidal impurities such as pigments, proteins, and pectic substances, forming a black-grey emulsion. Since the impurities cannot normally be filtered, they are purified by the lime carbonate cleaning method to obtain clean sugar juice.

Limestone becomes quicklime (CaO) when it is fired with coke in a firing furnace. When this is digested and added as lime milk (Ca (OH) ₂ ) to the crude sugar juice transferred to the lime treatment tank, it is introduced into the carbon dioxide gas filling tank and the carbon dioxide gas generated in the firing furnace is blown into it, (CaCO ₃ ) is produced. This lime carbonate is rich in adsorptivity and adsorbs colloidal impurities contained in the crude sugar juice in the thickener to coagulate and precipitate. Although this precipitate is fluffy and highly compressible, it is difficult to filter it. However, if lime is present, it becomes easy to filter and is discharged as a lime cake. As described above, limestone functions as an adsorbent for impurities and a filter aid, but the amount of limestone used is about 50 kg per ton of normal beet. Since about 140 kg of beet sugar is produced per ton of beet, about 180,000 ton of limestone is required for producing 500,000 ton of beet sugar per year. Therefore, the amount of lime cake discharged from the sugar factory also becomes quite large, but in general, there is no way to use it and it is currently disposed of as industrial waste. This limecake contains most of the lime consumed for sugar making, so if you look at it, it could potentially be consumed by the steel industry. However, as a sugar industry product used for iron making technology,
At most, it is about molasses used as an organic substance in the briquette method described above. On the other hand, lime cake contains a large amount of lime, but its crystals are so fine that it cannot be replaced with limestone that is directly charged into the blast furnace. Therefore, if it is used as a binder in a sintered ore or pellet ore as a blast furnace raw material, its development is desired.

The present invention has been made in view of the above problems, and an object thereof is to effectively use a lime cake discarded in a sugar factory for sintering or pelletizing a blast furnace raw material in a pig iron making process. To provide a method for producing a sintered ore or pelletized ore. The inventors of the present invention have paid attention to the fact that a lime cake discarded in a sugar factory contains a large amount of lime and that the lime is finely divided. Then, in various pretreatments of powdered ore for producing sinter or pellet ore as a blast furnace raw material, lime cake is added to iron ore to function as a desired binder, and further, addition of lime cake reduces the amount of lime cake. It was confirmed by conducting various studies whether or not a slag having a melting point can be produced and a predetermined desulfurization action can be performed, and as a result, the present invention has been completed.

[0011]

The present invention is applied to a method for producing a sintered ore as a blast furnace raw material by using a blended ore or the like. The feature is that 100% of the weight of the lime cake is added to the lime cake discarded from the sugar factory.
Add up to twice the amount of water to make a lime cake slurry. This lime cake slurry is added to a sintered ore raw material such as a blended ore in an amount of 10% by weight or less and kneaded into a lump. Then, the agglomerate is fired at a temperature up to about 1,400 ° C., and the fired agglomerate is cooled thereafter. Secondly, the lime cake discarded from the sugar factory is dried by heat at 100 ° C. to 500 ° C. so that the water content is 5% by weight or less, and the lime cake is pulverized into fine powder. The lime cake fine powder is added to a sinter ore raw material such as a blended ore and mixed to form a powder. Then, the powdery body is fired at a temperature up to about 1,400 ° C., and the lumps formed by firing are cooled thereafter. Thirdly, the lime cake discarded from the sugar factory is granulated to a size of 10 mm or less to prepare a granulated lime cake. This granulated lime cake is added to a sinter ore raw material such as a blended ore and molded into a lump. Then, the lumps are fired at a temperature up to about 1,400 ° C., and the fired lumps are cooled thereafter. In the step of granulating the lime cake, 10% by weight or more of powdered ore may be mixed. Unlike any of the above,
In a method of producing pellet ore as a blast furnace raw material using a blended ore, a lime cake slurry made into a slurry by adding water up to 100 times the weight of the lime cake to a lime cake discarded from a sugar factory. deep. Add 10% by weight or less of the lime cake slurry to a pellet raw material such as a blended ore for 10 mm to 30 mm.
Raw pellets are manufactured by granulating into spherical particles of about mm. And, the raw pellets are 1,200 ℃ to 1,300 ℃
That is, the fired pellets were fired, and the fired pellets were then cooled.

[0012]

According to the present invention, as described in the above-mentioned first, up to 100 times the amount of water is added to a lime cake to make a lime cake slurry, and 10% by weight of the sinter raw material is added.
Starting with the case of kneading into a mass in addition to the following,
In any case, the lime cake, which is a large amount of waste that is not used in the sugar mill, is used for the production of sinter or pellet ore that should be charged to the blast furnace during the ironmaking process. You can Most of the lime cake is not only limestone but also its lime is finely divided, and it is suitable for adding to a blended ore in which various kinds of powdered ores are mixed when producing sinter or pellet ore. It becomes a thing. In addition,
The lime cake can be used after being processed into various forms depending on its properties and the blast furnace raw material to be produced. Since lime cake also contains molasses, not only does sinter or pellet ore contain limestone,
It can also function as a binder for powdered ore. When the lime cake, which is an industrial waste, is used in the iron-making industry in this way, it is possible to reduce the consumption of limestone and to recycle the lime component, thereby saving resources. In addition,
In the step of granulating the lime cake, if the powdered ore of 10% by weight or more is mixed in advance, the amount of the powdered ore of the sintered ore raw material to which the granulated lime cake is added can be reduced. Not only that, the lime cake functions as a binder to improve the degree of binding of the powdered ore.
In addition, the sintering reaction and the melting or semi-molten reaction between the raw ore particles in the firing step are further promoted, and a self-fluxing sinter having a high porosity can be obtained.

[0013]

EXAMPLES The method for producing sinter as a blast furnace raw material using the lime cake according to the present invention will be described in detail below. Sintered ore is used in the ironmaking process when producing steel products through the ironmaking process, steelmaking process, rolling / surface treatment process,
Powdered ore, limestone, quicklime, sand iron, serpentine, coke, return ore, etc. were mixed as raw materials into the blended ore charged into the blast furnace together with iron ore, limestone, coke, etc. It is a thing. By the way, the blended ore
It is a blend of iron ore from each production area, and the components have been leveled in advance. When manufacturing a blast furnace raw material mainly composed of such a blended ore into a sintered ore, a lime cake discarded from a sugar factory is used, and the following procedure is taken. The lime cake is calcium carbonate (CaC
O ₃ ) is the main component, and has chemical and physical properties almost equal to limestone.

First, water is added to a lime cake up to 100 times the weight of the lime cake to form a slurry. Next, the iron ore charged into the blast furnace is crushed and sieved to prepare a fine ore having a diameter of 10 mm or less. Since there are many kinds of sinter ore raw materials and their components and particle sizes are different, these raw materials are mixed so that the components and particle sizes are adjusted to meet the sintering conditions. For example, the average particle size of the sintering raw material is usually preferably 2.0 mm to 4.0 mm, and it is preferable that the amount of the ultrafine powder is small in order to maintain the air permeability in the charging layer of the blast furnace. Powder coke is added to the powdered ore thus homogenized. The optimum value of this blended raw material varies depending on its properties, but it is generally the same as when adding an amount of water of about 6%, so that 10% by weight or less of lime cake is added to a sintered ore raw material made of blended ore. Add the slurry and knead into a mass. The basicity of the sinter is the most important factor in adjusting the sinter composition, and this is controlled by the blending amount of the lime cake slurry.

Next, the agglomerate is fired at a temperature of up to about 1,400 ° C. by using, for example, a Dwightroid type sintering machine. In this sintering machine, the air above the charged raw material layer is sucked downward to burn the coke mixed in the raw material, and the generated heat causes the sintering reaction and melting or semi-melting reaction between the raw ore particles. Is promoted. As a result, a self-fluxing sinter having a high porosity and a mineral composition different from that of iron ore can be obtained. A large amount of air is evenly flowed in the raw material layer in order to burn the powdered coke premixed with the charging raw material and efficiently perform the sintering reaction. Therefore, the particle size distribution of the raw material is adjusted in a pretreatment step for improving the ventilation resistance of the charging raw material layer, that is, the apparent particle size of the raw material particles is improved by the addition of the lime cake slurry, and the particles are collapsed during the transportation process. Can also be prevented. During this sintering process, calcium oxide (CaO) and silica sand (SiO ₂ ) combine to form a low-viscosity slag (CaO · SiO ₂ ), which improves the reducibility of the sinter. After that, if the fired body is cooled,
A relatively uniform particle size product is produced which also improves the permeability of the charge layer during hot metal operation. The sinter produced in this way is charged into a blast furnace together with large iron ore, limestone, coke, and the like. Limestone content has already been added to the sinter, and the amount of limestone charged at the time of charging the blast furnace can be reduced, and in the end, the limestone content consumed in the ironmaking process is at least that of lime cake. Only the amount used will be saved.

Even when lime cake is used instead of limestone, low-grade ore can be used as a raw material for iron making, as in the case of using limestone. Of course, harmful components such as sulfur in the raw material are removed during the sintering process, the chemical and physical properties of the raw material for blast furnace are improved, the productivity of the blast furnace is increased, and the fuel consumption is reduced. That is, by blending the lime cake in the sintering raw material,
Farelite (2), which is hard to reduce, is often produced in sinter.
FeO.SiO ₂ ) is reduced, and the sintered ore itself has appropriate grain size and strength, and has remarkably improved reducibility, high drop strength, and pressure resistance. As a result, it is possible to increase the mixing ratio of the sinter in the blast furnace raw material, and thereby increase the amount of tapped iron and decrease the ratio of the charging coke amount. Combined with the injection of heavy oil, a significant reduction in fuel consumption can be achieved.

As a method for producing a sintered ore using a lime cake, the following procedure different from the above may be adopted.
First, the lime cake is dried by heat such as 100 ° C. to 500 ° C. by a rotary dryer or the like so that the water content becomes 5% by weight or less. Originally, lime cake is very easily deformed, but dried lime cake is easily and easily pulverized by crushing. Next, 0.1 wt% or more of lime cake fine powder is added to the same sintered ore raw material as in the above-mentioned example and mixed into a powder. Then, the powdery material is subjected to 1,40 by a Dwightroid sintering machine or the like.
Bake at a temperature of up to about 0 ° C. The fired body is lumped and cooled to obtain a sintered ore. The self-fluxing sinter produced in this way can also sufficiently withstand as a blast furnace raw material, like the sinter described above.

As a method for producing a sinter using a lime cake, the following different procedures can be adopted. First, make 10 lime cakes using a pelletizer.
Granulate to a size of mm or less. The lime cake has some caking properties because it contains some sugar, but when the water content is low, a small amount of water necessary for granulation is added. Then, 0.1% by weight or more of granulated lime cake is added to the same sintered ore raw material as described above, and kneaded into a lump. Next, the agglomerate is dwitroid type sintering machine,
Baking is performed at a temperature up to about 1,400 ° C. Then, the fired body is cooled thereafter. The sinter produced in this manner also serves as a blast furnace raw material having the above-described functions and effects and can be charged into the blast furnace. In the granulation step of the lime cake, 10% by weight or more of powdered ore may be mixed in advance. In that case, it is possible to reduce the amount of powdered ore in the sinter ore raw material to which the granulated lime cake is added. Since the powdered ore is premixed with the granulated lime cake, the binding effect of the powdered ore is further improved by the binder action of the lime cake. Moreover, the sintering reaction and the melting or semi-melting reaction between the raw ore particles in the firing step are drastically promoted, so that a self-melting sinter having a high porosity can be obtained.

By the way, although there is the above-mentioned sinter as a poor ore treatment method, a pellet method as a lump-making method for making agglomerates is finer than a briquette method as mentioned in the prior art. There is. Therefore, it can be said that the lime cake that is likely to be in a finely divided state is suitable for the production of pellet ore. Therefore, a method for producing a pelletized ore using a lime cake as a blast furnace raw material using a blended ore will be described below. First, water is added to a lime cake up to 100 times the weight of the lime cake to form a slurry. Next, the particle size is 44μ or less 60% to 95%
And the specific surface area is 1,500 cm ² / g to 3,0
An extremely fine pellet raw material of 00 cm ² / g is prepared. A lime cake slurry of 10% by weight or less is added to the pellet raw material, and granulated by a pelletizer such as a boring drum or a boring disk. The raw material charged in the pelletizer rises along the wall with the rotation of the disc or drum and repeats the movement to fall inside,
Spherical raw pellets having a particle diameter of about 10 mm to 30 mm are formed by a snowman method. The raw pellets are required to be able to withstand impacts during transportation to the firing step and to have strength that can withstand pressure and abrasion during drying or firing. However, as described above, the lime cake slurry also contains molasses and has a function as a binder, and it is not required to add a binder. That is,
In the self-dissolving pellet to which the lime cake slurry is added, the lime cake functions as a binder and binds the ore grains. The basicity adjustment of this pellet ore is the most important part of the sintering component adjustment, but it is adjusted by the blending amount of the lime cake slurry. The raw pellets granulated as described above are subjected to 1, 2 or 2 by a vertical firing furnace (shaft furnace), a moving grate firing machine, a rotary kiln, or other firing equipment.
It is heated and baked at a high temperature of 00 ° C to 1,300 ° C. The sintered pellets are then cooled into spherical pellet ores of the order of 10 mm to 30 mm with sufficient strength to withstand drop impact and pressure during shipping and in the blast furnace. As described above, even when the lime cake is used for granulating raw pellets, the low-grade ore can be used as a blast furnace raw material. Of course, harmful components such as sulfur in the raw material are removed during the sintering process, and the chemical and physical properties of the blast furnace charging raw material are improved. Therefore, increase the productivity of the blast furnace,
A reduction in fuel consumption is realized. That is, by adding the lime cake in the raw pellets, less hard-to-reduce ferrite which is often produced in the pellets,
The pellet itself has an appropriate grain size and strength, and has remarkably improved reducibility, high drop strength, and pressure resistance. This makes it possible to increase the blending ratio of pellet ore in the blast furnace charging raw material, thereby increasing the amount of tapped iron and reducing the quantitative ratio of the coke charged.

As can be seen from the above description, the lime cake used in any of the examples is an industrial waste produced from a sugar mill that produces beet sugar, but as described in the prior art, lime carbonate is used. It contains a large amount of limestone used for purification by the cleaning method. Therefore, not only the molasses that is a regular product or a semi-finished product obtained in the sugar industry is used in the iron industry, but also a large amount of waste lime cake is charged into the blast furnace during the ironmaking process. It can be consumed for the production of sinter or pellet ore. This saves limestone and saves resources, and also eliminates the need for industrial waste treatment. In this way, lime cake can be used in place of limestone for the production of sinter or pellet ore because most of the lime cake is limestone, that the lime is finely divided, It is based on the fact that the suitable addition form proposed in the present invention can be selected when adding to the sintered ore raw material or the pellet raw material mixed with the powdered ore of No. In addition, the lime cake also contains molasses, and can also function as a binder for powdered ore and the addition of a binder can be omitted.

Claims (5)

[Claims] 1. A method for producing a sinter ore as a blast furnace raw material using a blended ore and the like, to a lime cake discarded from a sugar factory, water up to 100 times the weight of the lime cake is added to form a slurry. And a step of kneading into a lump by adding 10% by weight or less of the lime cake slurry to a sinter raw material such as the blended ore, A method for producing sinter ore as a blast furnace raw material using a lime cake, which comprises a step of firing at a temperature up to about ℃, and a step of cooling the fired lump. 2. A method for producing a sintered ore as a blast furnace raw material using a blended ore, wherein the lime cake discarded from the sugar factory has a water content of 5% by weight or less when heated at 100 ° C. to 500 ° C. So that the lime cake fine powder is finely pulverized and mixed, and the sinter ore raw material such as the blended ore is mixed with the lime cake fine powder and mixed to form a powder, and the powder is , A step of firing at a temperature of up to about 1,400 ° C., and a step of cooling the agglomerates formed by firing thereafter, as a blast furnace raw material using a lime cake. Manufacturing method of sinter. 3. A method for producing a sintered ore as a blast furnace raw material using a blended ore, etc., wherein a lime cake discarded from a sugar factory is granulated to a size of 10 mm or less to obtain a granulated lime cake. A step of adding the granulated lime cake to a sintered ore raw material such as the blended ore to form a lump, and firing the lump at a temperature of up to about 1,400 ° C. A method for producing sinter ore as a blast furnace raw material using a lime cake, comprising the step of subsequently cooling the calcined lump. 4. Sintering as a blast furnace raw material using the lime cake according to claim 3, wherein 10% by weight or more of powdered ore is mixed in the step of granulating the lime cake. Manufacturing method of ore. 5. A method for producing pellet ore as a blast furnace raw material using a blended ore, etc., wherein water is added to a lime cake discarded from a sugar factory up to 100 times the weight of the lime cake to form a slurry. And 10 mm to 3% by weight of the lime cake slurry is added to the pellet raw material such as the blended ore.
A step of producing raw pellets by granulating into spherical particles of about 0 mm, a step of firing the raw pellets at 1,200 ° C to 1,300 ° C, and a step of cooling the fired pellets thereafter. A method for producing a pellet ore as a blast furnace raw material using a lime cake, comprising: