KR101375061B1 - Process for producing granules of iron ore raw material, and granules of iron ore raw material - Google Patents

Abstract

The manufacturing method of the granulated material of an iron ore raw material has 0.01-10 mass parts of polymeric surfactants which have a hydrophobic group and an acidic functional group, and have a molecular weight of 10000-30000 with respect to 100 mass parts of total amounts of the iron ore raw material which consists of a powdered iron ore, CaO, and Ca (OH) with one or two of Ca ₂ (OH) total 0.5 parts by mass or more in terms of the _2, it comprises a step of adding water, 3 to 25 parts by weight.

Description

Manufacturing method of iron ore raw material and granulated iron ore raw material {PROCESS FOR PRODUCING GRANULES OF IRON ORE RAW MATERIAL, AND GRANULES OF IRON ORE RAW MATERIAL}

TECHNICAL FIELD This invention relates to the manufacturing method of the granulated material of an iron ore raw material, and the granulated material of an iron ore raw material. This application claims priority based on Japanese Patent Application No. 2010-228908 for which it applied to Japan on October 8, 2010, and Japanese Patent Application No. 2011-178956 for which it applied in Japan on August 18, 2011. Claim and use their content here.

Generally, as a raw material for blast furnace charging in a steelmaking process, water or a granulating agent is added to kneaded ore and kneaded to form a pseudo granulated product, and a sintered ore calcined in a sintering machine is used. In the firing step of the sintered ore, there is a problem that the pseudo granulated material is clogged in the sintered raw material filling layer, the air permeability is lowered, the combustion rate of coke which is the fuel is slowed, and the production efficiency of the sintered ore is lowered. Therefore, it is an important subject to obtain the granulated material which has favorable crushing strength which does not easily destroy the similar particle which comprises a similar granulated material, and also has good granulation property. The good granulation property means that the ratio which the particle size occupies is small among the similar particles which comprise a similar granulated material. For example, the ratio which the similar particle which has a particle diameter of less than 0.25 mm occupies is 3 mass% or less.

In recent years, high-quality iron ore raw materials are in a depleted direction. Therefore, the use of a poor quality iron-iron ore and pellet feed containing many fine powders has become a subject. Pellet feed is an inexpensive iron ore having an average particle diameter of about 10 to 100 µm, in which iron ore containing less iron is pulverized and washed with water to increase the iron content. This pellet feed has little gangue components of Al and Si, so the advantage of using a large amount is large. However, since the surface of the ore is smooth and contains almost no ultrafine powder of 10 µm or less, it is a poorly granulated ore and, when used, impairs air permeability in the sintered layer.

In order to obtain granules having good granularity, quicklime is now widely used as a binder having a binder function. This is because when quicklime is used, it is easy to obtain a granulated material having good granularity, and the crush strength of the obtained analogous particles is high and is hard to collapse.

However, in the case of using quicklime, a sufficient effect is not obtained unless the usage is increased. Moreover, even if 2 mass% or more of quicklime is added, since the improvement effect of granulation property tends to be saturated, cost performance is not good.

In Patent Literatures 1 to 2, a granulating agent having a function of breaking not only a function as a binder but also an aggregate in which water is introduced and dispersed is disclosed. In addition, a method is disclosed in which water exhibits an effect of efficiently assembling a powdered iron ore by sufficiently dispersing the powdered iron ore. Moreover, the high molecular compound which has a carboxyl group is disclosed as a granulation agent which has the function not only as a binder but the function which destroys and disperse | distributes the aggregate which introduces water.

Japanese Patent Application Laid-Open No. 2004-076132 Japanese Patent Application Laid-Open No. 2004-076133

However, in the method disclosed by patent document 1 and patent document 2, the request which the ratio which the similar particle which has a particle diameter of less than 0.25 mm occupies is 3% or less cannot fully be satisfied.

The present invention provides a method for producing a granulated product of ferrous iron ore showing excellent granulation even when poorly granulated raw materials such as poor quality iron-iron ore or pellet feed containing fine powder are used. Specifically, the smaller the particle size occupies among the similar particles constituting the similar granulated material, and the proportion occupied by similar particles having a particle diameter of less than 0.25 mm is 3% by mass or less.

In order to solve the above problems and achieve these objects, the present invention employs the following means.

(1) That is, the manufacturing method of the granulated material of the iron ore raw material which concerns on one form of this invention has a hydrophobic group and an acidic functional group, and has a molecular weight of 10000-30000 with respect to 100 mass parts of total amounts of the iron ore raw material which consists of a powdered iron ore. The process of adding 0.01-10 mass parts of activators, 1 type, or 2 types of CaO and Ca (OH) ₂ in Ca (OH) ₂ conversion in total 0.5 mass parts or more and 3-25 mass parts of water is added.

(2) In the manufacturing method of the granulated material of iron ore raw material as described in said (1), the said iron ore raw material may be formed from the said iron ore and a pellet feed.

(3) In the manufacturing method of the granulated material of the iron ore raw material as described in said (2), when the mass ratio of the said iron ore and the said pellet feed is (100-x): x, x may be 2 or more and less than 90.

(4) In the method for producing a granulated product of the iron ore raw material according to any one of the above (1) to (3), the hydrophobic group is at least one or more of an alkyl group, an alkyl ester group, and an aryl group, and M is an alkali metal or an alkali. When the earth metal or NH ₄ is used, the acidic functional group is represented by a carboxyl group, sulfonic acid group, phosphoric acid group, sulfate ester group, -COOM, -SO ₃ M, -HMPO ₄ , -M ₂ PO ₄ , or -OSO ₃ M At least one or more of the salts may be sufficient.

(5) In the manufacturing method of the granulated material of iron ore raw material as described in said (4), the said iron-iron ore contains 0.25 micrometer or less fine particle, and the ratio of the ultrafine particle of 10 micrometers or less in the said microparticle is 20 mass% or more 70 You may be mass% or less.

(6) In the method for producing a granulated product of the iron ore raw material according to any one of (1) to (3), the iron ore contains fine particles of 0.25 mm or less, and the ultra fine particles of 10 μm or less in the fine particles. 20 mass% or more and 70 mass% or less may be sufficient as a ratio.

(7) The granulated material of the iron ore raw material of one embodiment of the present invention is composed of iron ore, has a hydrophobic group and an acidic functional group, and has a molecular weight of 0.0096 to 9.05 mass% and a calcined lime of 0.45 mass% of 10000 to 30000. You may contain the above.

(8) The granulated material of the iron ore raw material according to one embodiment of the present invention comprises 0.0096 to 9.05 mass% of a polymer surfactant having a hydrophobic group and a pellet feed, having a hydrophobic group and an acidic functional group, and having a molecular weight of 10000 to 30000, and calcined lime You may contain 0.45 mass% or more.

(9) In the granulated product of the iron ore raw material according to the above (8), x may be 2 or more and less than 90 when the mass ratio of the iron ore and the pellet feed is (100-x): x.

(10) In the granulated product of the iron ore raw material according to any one of (7) to (9), the hydrophobic group is at least one or more of an alkyl group, an alkyl ester group, and an aryl group, and M is an alkali metal or an alkaline earth metal. or in the case of NH _4, wherein the acidic functional group, carboxyl group, a sulfonic acid group, phosphoric acid group, sulfuric ester _{group, -COOM, -SO 3 M, -HMPO} 4, -M 2 PO 4, salts represented by -OSO ₃ M At least 1 type or more may be sufficient as it.

According to the said aspect of this invention, the granule which the proportion which the particle | grains which comprise small granules occupies among the particle | grains which comprise granules occupies is small, for example, the proportion which the similar particle which has a particle diameter of less than 0.25 mm occupies is 3 mass% or less is obtained. Can be. As a result, for example, a granulated product having a strength of 10 kgf / cm 2 or more can be obtained. Sufficient sintering productivity can be improved only by substituting the granulated material of the present invention which assembled granules which were conventionally performed as a binder with the granulated material of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows copolymers, such as ammonium polyacrylate and methyl polyacrylate, concerning embodiment of this invention.
2 is a diagram showing a basic structure of a sulfonic acid type three-dimensional polymer according to an embodiment of the present invention.
It is a figure which shows the copolymer of sodium polysulfonate and ethyl polyacrylate which concerns on embodiment of this invention.
It is a figure which shows the copolymer of sodium polycarbonate, polystyrene, etc. which concerns on embodiment of this invention.
It is a figure which shows the sodium polyacrylate which concerns on embodiment of this invention.
It is a figure which shows the copolymer of sodium polymaleate and polyethylene which concerns on embodiment of this invention.
It is a figure which shows the relationship between the collapse strength of the granulated material of the iron ore raw material and the addition amount of Ca (OH) ₂ which concerns on embodiment of this invention.

It is preferable that the iron ore raw material which consists of powdered iron ore which concerns on embodiment of this invention contains 10-50 mass% of microparticles | fine-particles of the particle diameter of 0.25 mm or less when sifting a powdered iron ore. By setting it as 10-50 mass%, granulation property becomes favorable and the granulated material with a big particle diameter is easy to be obtained. More preferably, the ratio of the 0.25 mm or less microparticles | fine-particles which occupy in a ferrite ore is 20 mass% or more and 45 mass% or less.

Moreover, it is preferable that the ultrafine particle of 10 micrometers or less occupies 5 mass% or more among the fine particles of 0.25 mm or less. More preferably, they are 20 mass% or more and 70 mass% or less. It is because this ultrafine particle will fully function as a binder when 20 mass% or more of ultrafine particles of 10 micrometers or less are contained in 0.25 micrometer or less fine particles. On the other hand, when more than 70 mass% of ultrafine particles of 10 micrometers or less are contained in 0.25 micrometer or less fine particles, it becomes difficult to disperse them.

In manufacturing the granulated material of iron ore composed of iron ore, when the total amount of iron ore raw material is 100 parts by mass, 0.01 to 10 parts by mass of a polymeric surfactant having a hydrophobic group and an acidic functional group and a molecular weight of 10000 to 30000, At least one type of CaO and Ca (OH) ₂ is added in total to 0.5 or more parts by mass and 3 to 25 parts by weight of water in terms of Ca (OH) ₂ to the iron ore raw material. The hydrophobic group refers to a nonionic functional group having low affinity with water. An acidic functional group means a group which dissociates in water and becomes a negative ion. In the polymer compound having only a carboxyl group not containing a conventional hydrophobic group, the effect of dispersing ultrafine particles in the presence of CaO and Ca (OH) ₂ was small. As a result, such iron ore raw materials are poorly granulated, have low strength, and are easily collapsed. Further, in terms of the Ca (OH) _2, the amount of the CaO amount, CaO in the food 56 and Ca (OH) ₂ from the food 74, Ca (OH) ₂ in terms of parts by weight = CaO parts by mass × 74/56 of the It did by doing.

(Polymer surfactant)

The inventors of the present invention have a hydrophobic group and an acidic functional group and add 0.01 to 10 parts by mass of a polymer surfactant having a molecular weight of 10000 to 30000 as a coagulant to 100 parts by mass of iron ore, thereby obtaining a granulated product having good granulation. Found.

When assembling an iron ore raw material made of iron ore, particles of 0.5 mm or less are attached to nuclear particles having a diameter of 1 to 3 mm to form pseudo particles. At that time, the ultrafine particles having a diameter of 10 µm or less function as a binder, but the ultrafine particles adhere to the nuclear particles.

The present inventors have the effect of actively dispersing ultrafine particles from nuclear particles even in the presence of CaO or Ca (OH) ₂ , which is said to reduce the dispersing effect by adding a polymer surfactant having a hydrophobic group and an acidic functional group (hereinafter, , "Dispersion effect of ultrafine particles" is found.

Assembly which conventionally includes only the acidic functional group of a carboxyl group, etc., such as sodium polyacrylate used in the assembly of the raw materials is, the ability to disperse the second derivative of the α-FeOOH or α-Fe ₂ O _3. However, the ultrafine particles in the raw material include clay such as kaolin in addition to α-FeOOH and α-Fe ₂ O ₃ , and in some cases powder coke and the like. A cohesive agent containing only an acidic functional group lacked dispersibility to clay or powder coke. In this invention, the polymeric surfactant which introduce | transduced the hydrophobic group in molecular structure in addition to an acidic functional group is used as a granulation agent. By the presence of a hydrophobic group, α-FeOOH or α-Fe ₂ O _3, but also tends to Klee minutes or even polymeric surfactant is adsorbed coke, estimates that increasing the dispersion effect of the ultra-fine particles.

In addition, the polymer surfactant according to the embodiment of the present invention has a function of dispersing CaO or Ca (OH) ₂ particles. This is presumed to be because the hydrophobic group of the polymer surfactant preferentially adsorbs to the particle surface of the particles of CaO or Ca (OH) ₂ . CaO mixed with ultrafine particles and uniformly reacted with water, or Ca (OH) ₂ added from the beginning, functions as a binder and binds ultrafine powders and nuclear particles. Compared with the binder effect by only the ultrafine particles, the binder effect can be more markedly stronger. By using the polymer surfactant according to the embodiment of the present invention, Ca (OH) ₂ can be uniformly dispersed between ultrafine powders and nuclear particles. Therefore, the binder effect can be effectively taken out with a small amount of CaO or Ca (OH) ₂ . The reason for adding 0.01-10 mass parts of the polymeric surfactant which has a hydrophobic group and an acidic functional group at the same time, and has a molecular weight of 10000-30000 with respect to 100 mass parts of iron ore at the time of granulation is as follows.

When content of a polymeric surfactant is less than 0.01 mass part, dispersion of ultrafine particles is inadequate and granulation property does not improve and the granulated material which has favorable granulation property cannot be obtained. Therefore, a lower limit is made into 0.01 mass part. When the content of the polymer surfactant is more than 10 parts by mass, the raw materials are slurried and a granulated product is not obtained, resulting in high cost. Therefore, an upper limit is made into 10.0 mass parts.

When the molecular weight of the polymer surfactant having a hydrophobic group and an acidic functional group exceeds 30000, it is difficult to dissolve in water. Therefore, the upper limit of molecular weight was 30000.

When the molecular weight of the high molecular weight surfactant having a hydrophobic group and an acidic functional group is 10000 or less, the function as a surfactant is insufficient. This is presumed to be due to insufficient size of the hydrophobic portion of the hydrophobic group.

The hydrophobic group is an alkyl group, an alkyl ester group, an aryl group, and the acidic functional group is represented by a carboxyl group, a sulfonic acid group, a phosphoric acid group, a sulfate ester group, -COOM, -SO ₃ M, -HMPO ₄ , -M ₂ PO ₄ , or -OSO ₃ M In the case of using a losing salt or the like, a granulated product having excellent granulation property can be obtained. In addition, M represents an alkali metal, alkaline earth metal, or NH ₄ .

(Quick lime, slaked lime)

In general, it has been considered that when quicklime and slaked lime are incorporated into a coagulant having a function of breaking down and dispersing aggregates, the dispersing effect is lowered. However, with respect to 100 parts by mass of iron ore, the inventors have combined 0.01 to 10 parts by mass of the above-described polymer surfactant with quicklime (CaO) and / or slaked lime [Ca (OH) ₂ ] in total in terms of Ca (OH) ₂ . By using 0.5 mass part or more, it discovered that the granulated material which has favorable granulation property and high crushing strength can be obtained as shown in the example of FIG.

In embodiment of this invention, when CaO is added, it reacts with the water in granulated material, and it changes to Ca (OH) ₂ . It is considered that the ultrafine particles and Ca (OH) ₂ having a diameter of 10 μm or less uniformly dispersed by the polymer surfactant function as a binder, and complement each other to strengthen the bond between the nuclear particles, thereby increasing the crush strength of the granulated product. .

When the addition amount of quicklime and / or slaked lime is less than 0.5 parts by mass in terms of Ca (OH) ₂ , the improvement of the crush strength of the analogous particles is insufficient. Therefore, the minimum of the total content of Ca (OH) ₂ conversion was made into 0.5 mass part. When the total content of Ca (OH) ₂ equivalent is more than 4.0 parts by mass, the effect of improving the crush strength of the granulated product is saturated, and the cost increases. Therefore, it is preferable to make the upper limit of the total content of Ca (OH) ₂ conversion into 4.0 mass parts.

(Amount of water added)

When the addition amount of water is less than 3 mass parts with respect to 100 mass parts of iron-iron ores at the time of granulation, the granulated material which has favorable granulation property cannot be obtained. Therefore, the minimum of the addition amount of water shall be 3 mass parts. This is considered to be because the dispersion effect of the ultrafine particles by the polymer surfactant is not sufficiently obtained.

When the added amount of water exceeds 25 parts by mass, the whole is slurried and a granulated product cannot be obtained, or adhesion of the granulator to the container wall surface is severe, resulting in a decrease in productivity. Therefore, the upper limit of the addition amount of water shall be 25 mass parts.

(Combination of pellet feed)

In this embodiment, even if a part of fine iron ore containing a lot of fine powder is substituted by a pellet feed, a favorable granulated material can be obtained. Pellet feed is an average particle diameter in which iron ore containing less iron is pulverized and washed with water to increase the iron content to about 65% by mass or more and to reduce the gangue component, for example, the Al ₂ O ₃ content to about 1.5% by mass or less. It is an inexpensive iron ore about 10-100 micrometers. The surface of the ore is smooth and contains very little ultrafine powder of 10 µm or less, and thus is poorly granulated. In this embodiment, as a particle diameter of a pellet feed, the thing of 90 mass% or more and the ratio of the ultrafine powder of 10 micrometers or less of 5 micrometers or less of 0.25 micrometers or less was used. The inventors added quicklime (CaO) and / or hydrated lime [Ca (OH) ₂ ] to 100 parts by mass of iron ore raw materials even in the iron ore raw material in which pellet feed was mixed with the iron ore, and by adding 0.01 to 10 parts by mass of the polymer surfactant. It was found that a granulated product having high crush strength of the similar particles, high strength even in the presence of water, and no differentiation or collapse was obtained. As for the compounding quantity of the pellet feed in an iron ore raw material, when mass ratio of a powdered iron ore and a pellet feed is set to (100-x): x, it is preferable that x is 2 or more and less than 90. When x becomes 90 or more, the intensity | strength of a granulated material may fall and the quantity of the granulated material of 0.25 mm or less may increase. On the other hand, when x is less than a second, a, the effect of reducing the gangue components such as Al ₂ O ₃ due to the use of the feed pellets is reduced.

(Composition of the assembly)

The granulated material of the iron ore raw material which consists of iron-iron ore which concerns on embodiment of this invention, or the iron ore raw material which consists of iron-iron ore and pellet feed is manufactured by the manufacturing method of the granulated material which concerns on said embodiment of this invention. The composition of the granulated product of iron ore is in addition to the main component of iron ore or a mixture of iron ore and pellet feed, and has a hydrophobic group and an acidic functional group and has a molecular weight of 0.0000 (= 0.01 / 104.01 × 100) to 9.05 having a molecular weight of 10000 to 30000. It is (= 10 / 110.5 * 100) mass%, calcined lime 0.45 (0.5 / 110.5 x 100) mass% or more. Moisture is not included in the composition. The component ratio of the element contained in a granulated material can be identified by fluorescence X-ray analysis and ICP (Inductively Coupled Plasma) emission analysis. The crystal phase in the granulated material can be identified by powder X-ray diffraction.

Example

As a raw material for producing the granulated material of the iron ore raw material, iron ore I and II were used. In Table 1, the components and particle size distribution contained in iron-iron ore I and II were shown.

When the iron-iron ores I and II are sieved to more than 5 mm, 2 to 5 mm, 1 to 2 mm, 0.5 to 0.25 mm, and less than 0.25 mm, they contain fine particles of 10 µm or less in the particles of 0.25 mm or less. The ratio is 20 mass% or more. The quantity of the ultrafine particles of 10 micrometers or less was measured with the laser diffraction type particle size distribution measuring apparatus about the sample of 0.25 mm or less.

Table 2 shows the names of the granulating agents of A to F. In addition, the molecular structures of the granulating agents A-F are shown in FIGS. 1-6, respectively. Granulating agent B is a polymer having a complex three-dimensional structure based on the structure of FIG. 2. The molecular weight was measured by weight permeation chromatography (GPC: Gel Permeation Chromatography). A-D is a polymeric surfactant which has a hydrophobic group and an acidic functional group which concerns on embodiment of this invention, The molecular weight is 10000-30000. E and F are polymer surfactants which do not contain hydrophobic groups, such as sodium polyacrylate.

Table 3 and Table 4 show the results of granulation using the granulation agents A to F of the iron-iron ores I and II. Table 3 shows the results of the examples and Table 4 shows the results of the comparative examples. Underline is given to the item which deviates from the preferable range in this embodiment.

Table 5 and Table 6 show the results of granulation using iron granules of A to F with respect to iron ore raw materials in which lyodose-PF or MBR-PF was mixed as pellet feed to powdered iron ores I and II. Table 5 shows the results of the examples and Table 6 shows the results of the comparative examples. Underline is given to the item which deviates from the preferable range in this embodiment.

Evaluation evaluated the case where both the granulation property and the crushing strength of the granulated material were passed as GOOD, and it failed as other than (POOR).

In the Example, the component ratio of the element contained in the granulated iron ore was identified by fluorescence X-ray analysis. In addition, the crystal phase in the granulated material was identified by powder X-ray diffraction. Table 3 shows the granulation agent content and Ca (OH) ₂ content in the granulated material.

About granulation property, the thing of the thing of 3 mass% passing and rejecting that the ratio of the similar particle | grains of less than 0.25 mm in a granulated material being less than 3 mass% was rejected.

Regarding the crush strength of the granulated product, 10 dry granulated products having a particle diameter of 4 mm to 6 mm are selected, and a load F (kgf) (hereinafter referred to as "collapse load") in which the granulated product is crushed by applying a load with a compression tester. ) Was measured and the average value of the value divided by the cross-sectional area S (cm 2) passed 10 kgf / cm 2 or more, and less than 10 kgf / cm 2 was rejected.

Here, the cross-sectional area was regarded as a sphere and the cross-sectional area S (cm <2>) of the surface which cut | disconnected the said sphere into the surface containing the center. That is, if the diameter of the sphere is d (cm), since S = π x (d / 2) x (d / 2), the crush strength P is calculated as P = F / S = 4F / πd ² . The diameter d of a granulated material measures the diameter of the granulated material, for example, measures the maximum value d _max and the minimum value d _min , and makes the average value d _a the diameter d of the granulated material.

The 10 kgf / cm 2 crush strength is about 10 cmf / cm 2 × 0.2 cm 2 = 2 kgf since the area of the cross section cut into a plane including the center of a sphere having a diameter of 5 mm is 0.2 cm 2 (≒ 0.25 cm × 0.25 cm × π). Load F corresponds to a granulated product having a diameter of 5 mm and collapses.

Hereinafter, each Example is described concretely.

(When assembling iron ore)

When iron ore I and II shown in Table 1 are 100 mass parts, iron ores I and II which dissolve the granulation agents A to F and water by the formulations shown in Tables 3 and 4, and are prepared together with CaO or Ca (OH) _2. Was added to 100 parts by mass of to form a granulation process. In the granulation, the fan mixer was rotated for 5 minutes at a rotational speed of 20 min ⁻¹ . The result of granulation was described in Examples 1 to 44 of Table 3 and Comparative Examples 1 to 25 of Table 4. Comparative Examples 1 to 6 do not contain CaO or Ca (OH) ₂ .

Since the ratio which the similar particle | grains of less than 0.25 mm occupy is 3 mass% or less, and the crush strength test result is also 10 kgf / cm <2> or more, Examples 1-44 pass. On the other hand, as in Comparative Examples 1 to 25, when it does not contain CaO or Ca (OH) ₂ , when a coagulant outside the preferred range is used or when the amount of the coagulant added is outside the preferred range, similar particles smaller than 0.25 mm The ratio occupies more than 3 mass%, and also the crush strength test result was less than 10 kgf / cm <2>, and failed. Even when the granulated products of Examples 1 to 44 were immersed in water, the granulated materials did not collapse and were excellent in water resistance.

(When pellet feed is mixed with iron ore)

CaO and / or Ca (OH) ₂ is added when lyodose-PF or MBR-PF is mixed as a pellet feed to the iron-iron ore I or II shown in Table 1, and these total amounts are 100 mass parts, Furthermore, 0.01-10 mass parts of granulation agents A-F were melt | dissolved in 3-25 mass parts of water, and the granulation process was performed in addition to 100 mass parts of prepared iron ore raw materials. In the granulation, the fan mixer was rotated for 5 minutes at a rotational speed of 20 min ⁻¹ .

About the result, Examples 45-73 are shown in Table 5, and Comparative Examples 26-35 are shown in Table 6.

Since the ratio which the pseudo particle | grains of less than 0.25 mm occupy is 3 mass% or less, and the crushing strength test result is 10 kgf / cm <2> or more, Examples 45-73 have passed. On the other hand, in the case of using a dispersant outside the preferred range as in Comparative Examples 26 to 35, or when granulating using only pellet feed containing no iron ore, the proportion of similar particles smaller than 0.25 mm is more than 3% by mass, The crush strength test result is also failed because it is less than 10 kgf / cm 2. Even when the granulated products of Examples 45 to 73 were immersed in water, the granulated materials did not collapse and were excellent in water resistance.

It Ca (OH) in the vicinity of the lower limit of 0.5 parts by weight of the amount of addition of _2, to elucidate the relationship between the addition amount of Ca (OH) ₂ and the assembly performance and strength, was subjected to the experiment. 30 parts by mass of lyodoce-PF was mixed as a pellet feed to 70 parts by weight of the iron-iron ore I shown in Table 1, and the total amount thereof was used as an iron ore raw material having 100 parts by mass. And were subjected to a Ca (OH) ₂ 0 to 0.65 parts by weight, the assembly B 0.3 parts by weight, the granulation were dissolved in 10.0 parts by weight of water, it was added to 100 parts by mass of iron ore raw material prepared in the above. In the granulation, the fan mixer was rotated for 5 minutes at a rotational speed of 20 min ⁻¹ . The results are shown in Examples 74 and 75 and Comparative Examples 36 to 39 in Table 7. The relationship between the collapse strength of these granules and the addition amount of Ca (OH) ₂ is shown in FIG. 7. At 0.5 mass part or more which is a minimum of Ca (OH) ₂ addition amount of this invention, crushing strength improves significantly and it exceeds the strength of 10 kgf / cm <2> or more.

(Productivity of Sintered Ore)

In this embodiment, sufficient sintering productivity can be improved by substituting the granulated material of the iron ore raw material which concerns on this embodiment by replacing part or all of the granulated material which assembled the quicklime which was conventionally performed as a binder.

As productivity of a sintered ore, it can measure by the yield of a sintered ore and the sintering time. For example, the product yield can be evaluated by measuring the ratio of particles having a particle size of 5 mm or more when the sintered ore (sinter cake) after sintering is dropped five times on an iron plate from a height of 2 m in the sinter crucible test. Can be. In addition, a production rate can be computed by the following formula | equation.

Production rate (t / day / m 2) = total mass (t) / sintering time (day) / sintering machine (crucible) surface area (m 2) of particles having a particle size of 5 mm or more after evaluation of product yield

Specific examples are shown. Minutes that are shown in Table 1 Ⅰ iron ore, iron ore fines or Ⅱ Ⅰ, the addition of calcium oxide 1.0 parts by weight of coke and water in any parts of the 100 parts by weight of a mixture of the Ⅱ pellet feed material, and in a drum mixer for 20min ^-1 A granulated product (hereinafter referred to as a conventional granulated product) assembled for 5 minutes at a rotational speed was produced. The granulated material which concerns on this embodiment was added to this conventional granulated material, and it mixed for 1 minute by the rotation speed of 20min- ^{1 in} a drum mixer. In order to measure the amount of water, 500 g of the raw material after mixing was dried at 150 ° C. for 2 hours, and the weight before and after drying was measured. The quantity of coke was mix | blended so that it might become 4.5 mass parts with respect to all the raw materials. Using these raw materials, sintering was performed by the crucible test of 70 kg scale, and the sintered ore was obtained. The sinter crucible was 300 mm in diameter, 650 mm in height, and 500 mm in layer thickness, and the suction negative pressure was 9.8 kPa (constant) as the conditions of the said test. The production rate of the obtained sintered ore was measured. These results are summarized in Table 8.

Examples 76-87 are the result of the sintering production rate at the time of replacing the granulated material which concerns on embodiment of this invention, or the granule which concerns on embodiment of this invention in part or all. Comparative Examples 40-46 are the result when using only the conventional granulated material which does not contain the granulated material which concerns on embodiment of this invention, or when using the granulated material outside the preferable range in this embodiment. Sintering productivity failed less than 26% and made 26% or more the pass. In Examples 76-87 using the granulated material which concerns on embodiment of this invention, all high sintering production rates are achieved.

According to the manufacturing method of the granulated material of iron ore raw material which concerns on embodiment of this invention, the ratio which the particle | grains which comprise the granulated material with a small particle diameter occupies is small, for example, the particle | grains which have a particle diameter of less than 0.25 mm occupy. The granulated material which is 3 mass% or less can be obtained. As a result, for example, a granulated product having a strength of 10 kgf / cm 2 or more can be obtained. Moreover, sufficient sintering productivity can be improved only by substituting the granulated material of the granule which assembled the quicklime which was conventionally performed as a binder with the granulated material of this invention.

Claims (10)

With respect to 100 parts by mass of the total amount of iron ore raw material composed of iron ore,
0.01 to 10 parts by mass of a polymer surfactant having a hydrophobic group and an acidic functional group and having a molecular weight of 10000 to 30000,
0.5 part by mass or more of one or _two of CaO and Ca (OH) ₂ in terms of Ca (OH) ₂ ,
3-25 mass parts of water,
The manufacturing method of the granulated material of an iron ore raw material characterized by including the process of adding. The manufacturing method of the granulated material of iron ore raw material of Claim 1 characterized by the said iron ore raw material consisting of the said iron-iron ore and a pellet feed. The method for producing a granulated product of iron ore raw material according to claim 2, wherein x is 2 or more and less than 90 when the mass ratio of the iron-iron ore and the pellet feed is (100-x): x. The said hydrophobic group is at least 1 sort (s) of an alkyl group, an alkylester group, and an aryl group, in any one of Claims 1-3,
When M is an alkali metal, an alkaline earth metal, or NH ₄ , the acidic functional group is a carboxyl group, sulfonic acid group, phosphoric acid group, sulfate ester group, -COOM, -SO ₃ M, -HMPO ₄ , -M ₂ PO ₄ , -OSO ₃ M salt at least one member, the manufacturing method of water assembly of the iron ore raw material, characterized in that at least one represented by the following. 5. The granulated iron ore raw material according to claim 4, wherein the iron-iron ore contains fine particles of 0.25 mm or less, and the ratio of ultrafine particles of 10 μm or less in the fine particles is 20% by mass or more and 70% by mass or less. Method of making water. The said iron-iron ore contains microparticles of 0.25 mm or less, and the ratio of the ultrafine particle of 10 micrometers or less in the said microparticles is 20 mass% or more and 70 mass% or less. The manufacturing method of the granulated material of iron ore raw material characterized by the above-mentioned. Made of iron ore,
The granulated material of iron ore raw material which has a hydrophobic group and an acidic functional group, and contains 0.0096-9.05 mass% of polymeric surfactants with a molecular weight of 10000-30000, and 0.45 mass% or more of hydrated lime. Consisting of iron ore and pellet feed,
The granulated material of iron ore raw material which has a hydrophobic group and an acidic functional group, and contains 0.0096-9.05 mass% of polymeric surfactants with a molecular weight of 10000-30000, and 0.45 mass% or more of hydrated lime. The granulated material of the iron ore raw material according to claim 8, wherein x is 2 or more and less than 90 when the mass ratio of the iron-iron ore and the pellet feed is (100-x): x. The said hydrophobic group is at least 1 sort (s) of an alkyl group, an alkylester group, and an aryl group,
When M is an alkali metal, an alkaline earth metal, or NH ₄ , the acidic functional group is a carboxyl group, sulfonic acid group, phosphoric acid group, sulfate ester group, -COOM, -SO ₃ M, -HMPO ₄ , -M ₂ PO ₄ , that at least one or more kinds of the salts represented by -OSO ₃ M, characterized in, granulated iron ore raw material.

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