JP5532986B2 - Method for adjusting the appropriate amount of moisture during the production of granulated and sintered raw materials - Google Patents

Description

  The present invention relates to a method for adjusting an appropriate amount of moisture when producing a granulated and sintered raw material to be supplied to a sintering machine, and in particular, produces a granulated and sintered raw material using a sintered raw material blended in a mountain ( This also relates to a method for accurately adjusting an appropriate amount of water during granulation.

  Sinter is usually made from powdered iron ore of several brands (hereinafter also referred to simply as “ore”), secondary raw material powders such as limestone, quartzite, and serpentine, and miscellaneous raw materials such as dust, scales, and return minerals. And a granulated sintered raw material, which is mixed with a solid material such as powdered coke and appropriate amounts, mixed with a drum mixer or a disk pelletizer, and pseudo-particles are produced. It is obtained by charging the granulated and sintered raw material onto a pallet of a sintering machine, igniting the solid fuel in the surface layer portion of the charged layer, and firing it under downward suction.

  Generally, when a sintered ore is produced using a DL sintering machine, the properties of the granulated and sintered raw material affect the air permeability of the charging layer, and consequently the quality, productivity or yield of the sintered ore. It is well known that On the other hand, in the production of granulated and sintered raw materials, moisture plays a major role as a binder that attaches fine powder in the sintered raw materials to the surface of the coarse particles (core particles). Therefore, it is important to adjust the amount of water appropriately.

Therefore, conventionally, various attempts have been made to control the moisture content of the sintering raw material during granulation for the purpose of promoting the action of quasi-particle formation by imparting adhesion to fine powder and core particles. .
For example, in Patent Documents 1 and 2, the saturated moisture value of each powdery substance constituting the sintering raw material is obtained in advance, and sintering is performed by a weighted average from each saturated moisture value and the blending ratio of each powdery substance. A method is disclosed in which a saturated moisture value of a raw material is calculated, and a certain proportion of the weighted average saturated moisture value is added to the sintered raw material for granulation.

  In Patent Documents 3 and 4, the critical moisture concentration, which is the lower limit value of the moisture concentration at which the sintered raw material after the addition of water has adhesion, is calculated from the water absorption rate of the sintered raw material and the particle size distribution before granulation. A granulation method is disclosed in which the amount of moisture added is controlled so that the moisture concentration of the ligation raw material is equal to or higher than the critical moisture concentration.

  By the way, in recent years, there is a tendency to increase the blending rate of ores with high water absorption, such as pisolite ore and maramamba ore, as a sintering raw material. In the case of a sintering raw material containing a large amount of these ore with high water absorption, appropriate granulation water concentration can be accurately predicted with control based solely on indices such as saturated water value and water absorption rate, as in the prior art. It is difficult to determine the appropriate range of the amount of water added during granulation with high accuracy.

  In addition, while maramamba ore has a lot of fine powder, some of the psolite ore has a large amount of coarse particles.Therefore, the grain size composition of the sintered raw material varies greatly due to changes in the ore brand and raw material composition. Along with this, there is a possibility that the appropriate granulated water concentration also varies greatly. Therefore, the management of the granulation moisture concentration has become much more important than before, and there is an urgent need to develop a technology that can predict the proper granulation moisture concentration with higher accuracy.

  In order to solve such a problem, in Patent Document 5, in addition to the water retention rate of the sintering raw material, the open pore volume in the particle size range of 3 to 5 mm is also considered, and the actual particle size distribution and the standard particle size are further considered. The calculation method of the optimal granulation moisture concentration of a sintering raw material is disclosed by taking into account the amount of deviation caused by the difference from the distribution. And even if it mix | blends a large quantity of inferior ores with high absorbability and a particle size structure greatly different as a sintering raw material by this method, it is supposed that the optimal granulation water density | concentration can be estimated accurately.

Japanese Patent Publication No. 3-80849 Japanese Patent Laid-Open No. 5-51654 Japanese Patent Laid-Open No. 11-61281 JP 2000-1725 A Japanese Patent Laid-Open No. 2008-1960

By the way, in recent years, as a raw material for sintering, as the price of iron ore has risen, it has been in a situation where an inexpensive inferior ore has to be used, and in order to obtain a cheaper raw material, it has been previously blended in Yamamoto. There is a move to buy crushed ore. In Yamamoto, the iron grade of the mined powder ore, the components such as SiO ₂ and Al ₂ O ₃ are adjusted and shipped by the beneficiation, but if the purchase side relaxes the beneficiation standards, the purchase price will be lowered although the quality will be lowered. Can be suppressed. Against this background, the possibility of using blending ores is expected to increase as raw material prices rise.

  Conventionally, when producing pseudo-particles that are granulated and sintered raw materials, the amount of water for making the pseudo-particles is the open porosity of simple raw materials (raw materials consisting of a single brand) constituting the sintered raw materials, Calculation is based on basic physical properties such as water retention rate and blending ratio. However, in this case, when trying to use the ore blended at the foot of the mountain, the type and blending ratio of the blended ore are often unknown, so that there has been a problem that the conventional method for predicting the appropriate water content cannot be applied.

  Therefore, the present invention is suitable for the proper moisture content at the time of granulation, even when using a sintering raw material such as blending ore in which the ore species and the blending ratio of each ore species are unknown, so-called Yamamoto, where multiple brands of ores are mixed. A method for adjusting the proper moisture content at the time of granulated sintered raw material production, which can accurately predict the amount, taking into account the effects of auxiliary materials, and can determine the amount of water added during granulation with higher accuracy. The purpose is to propose.

In order to solve such problems, in the present invention, pseudo-particles are obtained by adding water to a sintered raw material containing iron ore, auxiliary raw materials, miscellaneous raw materials and solid fuel core particles and fine powder, and mixing and granulating the mixture. In the method of adjusting the appropriate moisture content when producing the granulated sintered raw material,
Before water addition to the sintering material, moisture absorbed index sintered material, adhering moisture index, obtains a correction index Hazuki group index of these, suitability granulation water necessary for the pseudo-particles An amount of water is estimated and the amount of water added is determined so that the estimated appropriate amount of granulated water is obtained.

In the present invention,
(1) that before the iron ore of the Kishoyui raw material, in which compounding ore types and mixing ratio is contained in at least a portion of the unknown blending ore,
Is preferred.

(1) According to the present invention, the sintered raw material can be easily and accurately made into pseudo particles (granulated) at the time of granulation, and a high-strength granulated sintered material (pseudo particles) is produced. As a result, it is possible to obtain a granulated and sintered raw material useful for ensuring the air permeability of the charging layer at the time of firing in a sintering machine.
(2) In the present invention, even when blending ore with an unknown type or blending ratio of blended iron ore is used as a sintering raw material, an appropriate amount of granulated water in granulation, Since it can be determined accurately and easily in consideration of the auxiliary raw material blending conditions, it is possible to predict the moisture content more accurately.
(3) Therefore, according to the present invention, the quality, productivity, and yield of the sintered ore can be further improved.

It is a schematic diagram of the sintering pot apparatus for a test used in order to confirm the effect | action of this invention. It is a graph which shows the influence of the granulation (pseudoparticle) water | moisture content which acts on the air permeability of a sintering charge layer, and a pseudoparticle diameter. It is a figure explaining the mechanism of appropriate granulation (pseudo particle) moisture. It is a graph which shows the influence of the particle diameter (1 / dp) which acts on a moisture content. It is a flowchart which shows the outline of the whole sinter manufacturing process. It is a graph which shows the relationship between the estimated value of the appropriate granulation moisture value in the case implemented by applying the conventional method, and an actual measurement value. It is a graph which shows the relationship between the estimated value of the appropriate granulation water value, and the actual measurement value in the case implemented by applying the method of the present invention. It is a graph which shows the comparison result of the conventional method and this invention method of the ventilation | gas_flowing fluctuation | variation during operation.

  The inventors produce a granulated (pseudo-particle) sintered raw material (granulated) using a sintered raw material containing so-called blending ore whose sintering raw material (ore type) is unknown because it is blended at the mountain base. ), Prior to the granulation, obtain the “absorption moisture index”, “adhesion moisture index”, and correction index (“chemical composition”, “wettability”) of the iron ore and auxiliary materials in the sintering raw material. , Using these indexes and the appropriate moisture predicted value calculated based on the blending ratio of each raw material, it was found that granulation (pseudo-particle formation) is performed stably and appropriately, the present invention Completed.

Hereinafter, the concept of the present invention will be described with respect to a method for determining the amount of proper granulation moisture required at the time of granulation of the sintered raw material.
FIG. 1 shows a schematic diagram of the experimental pan equipment used for investigating the influence of the granulated water concentration on the pseudo particle diameter and air permeability. For the powdered ore used, for each plain ore brand, the moisture content was changed in various ways while sequentially changing the amount of water added, and the mixture was granulated with a drum mixer. The particles were filled into the test sintering pan, and the air was sucked downward in the cold to calculate a cold air permeability index JPU (Japan Permeability Unit) from the following equation (1). In addition, JPU is a value which shows that air permeability is so favorable that it is large.

JPU = V / S (h / ΔP) ⁰ ... (1)
Here, each coefficient is V: air volume [Nm ³ / min],
S: sectional area of packed bed [m ² ],
h: packed bed height [mm],
ΔP: Pressure loss [mmH ₂ O]
It is.

  In the figure, 1 is an orifice, 2 is an air box, 3 is a test sintering pot (φ150 mm), 4 is a great, 5 is a Pitot tube, 6 is a differential pressure gauge, and 7 is a suction blower. In FIG. 3, 8 is fine powder, 9 is core particles, 10 is pores, 11 is ore particles, 12 is moisture, 13 is pseudo particles, 14 is cross-linked water, 15 is adhering water, 16 is added water, 17 is A raw material hopper, 18 is a conveyor, 19 is a drum mixer, 20 is a conveyor, 21 is a feeding hopper, 22 is a sintered pallet, and 27 is a sintered ore.

  FIG. 2 shows the measurement results of pseudo particle diameter (harmonic mean diameter) and air permeability (JPU) when the moisture concentration of the granulated product is changed for two types of ores (A ore and B ore). As is clear from this figure, although the particle size of the pseudo particles increases with the addition of moisture, it is understood that the granulated moisture (appropriate granulated moisture) that maximizes the air permeability (JPU) varies depending on the raw material.

  FIG. 3 shows the concept of granulated moisture. That is, the granulated moisture when the sintered raw material is granulated to produce pseudo particles is based on the relationship between the air permeability (JPU) and pseudo particle diameter and pseudo particle moisture (granulated moisture) shown in FIG. It is considered that there are three stages in how granulated water relates to ore particles: absorption (A), adhesion (B), and crosslinking (C). Hereinafter, the concept of each stage and the factors affecting the moisture during granulation will be described.

(1) Absorption (A): How water is absorbed into iron ore particles is expressed as “absorbed water index”. The absorbed water index is considered as follows.
In the graph of FIG. 3, it can be seen that in the region (A) where the ores are dispersed individually, the effect of moisture addition does not significantly affect both the pseudo particle diameter and the air permeability. As shown on the right side of the figure, as (A) region, there are fine open pores 10 on the surface of the ore particles 11, and the added water 12 is used to first penetrate into the voids. It is expected to be. From this, it is considered that the water necessary for granulation increases as the amount of pores and the amount of voids increase, and is consumed in the moisture contained therein.

(2) Adhesion (B): How the moisture affects the adhesion action (adhesion moisture index) of the fine powder to the core particles can be described as “particle size distribution”, that is, the mass ratio of the fine powder and the core particles.
When water is further added from the state of FIG. 3A, an area of (B) in the figure is obtained, and in this area, as shown as (B) area on the right side of the figure, adhering water 15 that wets the surface of the ore particles 11 is obtained. When it comes into contact with the adjacent ore particles 11, it acts as the crosslinking water 14. The so-called pendular, fanicular, and capillary regions are used. In this case, the contact between the ore particles 11 proceeds, and the fine powder 8 adheres to the surface of the core particles 9. As a result, the diameter of the pseudo particles 13 is increased and the powder ratio in the sintered raw material is decreased. Also goes up.

FIG. 4 is a diagram showing the influence of the particle diameter on the moisture content after suction filtration of an immersion sample for two types of ores (A ore and B ore). The horizontal axis represents the specific surface area 1 / dp [mm ⁻¹ ] of the submerged sample particle diameter. As is apparent from FIG. 4, it can be seen that the smaller the particle size, the larger the specific surface area and the more the adhering moisture. That is, it shows that the larger the mass ratio of the fine powder in the raw material, the larger the amount of attached water and the more water necessary for granulation.

  In other words, the amount of adhering moisture varies depending on the particle diameter, so it can be said that it is influenced by the “particle size distribution”. That is, when a large number of particles having a large particle size are present in the sintered raw material, the fine particle ratio is reduced, so that the water necessary for granulation is reduced. Depending on the raw material, the composition of the fine grain side (generally -1 mm) and the coarse grain side (+2 mm) are greatly different, so the coarse grain ratio is also an important index.

(3) Crosslinking (C): In determining the appropriate amount of granulated moisture, not only the above-mentioned “absorbed moisture index” and “adhesion moisture index” but also a correction index ( As the correction term), it is necessary to take into account at least one of the cross-linking water between the powders, that is, the “water wettability” and the “chemical component” of the powder.
a. Hereinafter, the “wettability” with the water will be described first.
In general, when the pseudo particles are regarded as wet agglomerated powder, the estimation formula of the pseudo particle strength σ can be expressed as the following formulas (2) and (3).
σ = ψ · S · Pc (2)
Pc = 6 · (1−ε) / ε · γ / Ds · cos θ (3)
Where each coefficient is
σ: Granule strength [N],
ψ: liquid fullness [−],
S: powder surface area [m ² ],
Pc: Suction pressure [Pa]
ε: porosity of the granule [−],
γ: surface tension of water [N / m],
Ds: specific surface area sphere equivalent diameter [m],
β: Contact angle with powder [°]
It is.

  It can be seen from the above formula that the strength of the pseudo particles composed of powder that is easy to wet (small contact angle) is large, and the strength of the pseudo particle composed of powder that is difficult to wet (large contact angle) is small. And if the wettability between the powder and water is poor, water (cross-linking water) is not retained in the aggregated powder, and water easily oozes out of the aggregated powder, and the excess moisture for that causes voids between the pseudo particles. Is buried and impairs breathability. That is, it is expected that a raw material with poor wettability will have less appropriate moisture. In addition, wettability with water, which is the wettability of powder with water, can be measured by various physical methods.

b. Next, the “chemical component” as the correction index will be described.
Here, the influence which the clay structure | tissue in an ore has on appropriate water | moisture content is demonstrated. Generally, iron ore contains a small amount of kaolin mineral, which is a clay mineral. The kaolin mineral is an aluminum hydrated silicate mineral (a kind of clay mineral), and the Al ₂ O ₃ mass ratio is about 30 to 40%. The particle size of kaolin mineral is as fine as several μm and is highly water-absorbing. That is, it is considered that when the Al ₂ O ₃ mass ratio in the raw material increases, the moisture necessary for granulation increases excessively.

Further, SiO ₂ in the ore are also believed to affect the proper amount of water. Sinter must be used as a stable raw material in a blast furnace, and slag component values such as SiO ₂ , Al ₂ O ₃ , MgO, and CaO / SiO ₂ are strictly controlled. In particular, since SiO ₂ differs from 3 to 8 mass% depending on the ore, it is necessary to adjust the blending with auxiliary materials such as silica. That is, in ores with low SiO ₂ content, silica is increased, and in the opposite case, silica is reduced. Since silica is a raw material with poor absorption water, it is considered that the required water content of the charging raw material is reduced by increasing the distribution of silica.

  When water is further added from the state shown in FIG. 3B, the state shown in FIG. 3C is obtained. As shown in the region (C) on the right side of the drawing, the water becomes excessive, so the added water 16 This is a so-called slurry region in which is continuously present. In this case, although the particle size increases, the porosity of the charging layer decreases due to excess water, leading to a decrease in air permeability.

From the above, the appropriate amount of granulated water (Wopt) when focusing only on iron ore is the “absorbed moisture index”, “adhesion moisture index” of the sintered raw material particles, and other such indexes are raised. The correct moisture content at the time of granulation can be determined with higher accuracy when correction is made in consideration of the correction index obtained from “wetability with water” and “chemical composition” which are correction terms for It is thought that it will become. That is, the proper granulation moisture amount (Wopt) when mixing and granulating the sintering raw material can be determined under the concept of the following formula.
(Wopt) = (Absorbed moisture) + (Adhered moisture) + (Correction index) (4)

  In the present invention, in particular, even when a blended ore type or blending ratio is unknown, that is, blending ore, before the addition of moisture, the sintered raw material (blending ore-containing material) and sub-material “ If the “absorption moisture index” and “adhesion moisture index” and the “correction index” (chemical component, wettability with water) are given, the appropriate granulated moisture content of the sintering raw material based on the above equation (4) Therefore, the amount of water added during granulation can be determined with higher accuracy.

  As a result, for example, proper blending (pseudo-particle formation) can be achieved even when blending ore with unknown ore type and blending ratio is used. Therefore, high-strength pseudo-particles (granulated sintered raw materials) are always obtained. It is done. As a result, the air permeability of the charging layer at the time of firing by the sintering machine becomes good, which contributes to improvement in quality of the ore, productivity, and yield.

Hereinafter, the method for estimating the appropriate granulated moisture content performed in the method of the present invention will be described. First, raw materials to be used are sampled, and physical property measurement and chemical analysis are performed.
(A) About “Absorbed Moisture Index”
As the absorbed moisture index, chemical analysis values such as LOI (ignition loss) and CW (bound water) can be used for both iron ore and auxiliary materials, but the amount of pores may be used as the absorption index. The amount of pores was determined by calculating the total volume of open pores having a diameter of 0.003 μm to 200 μm by a mercury intrusion method for a powdery substance obtained by regulating the dried sintered raw material to a diameter of 4 to 6.7 mm. Use the value converted per unit mass.
In addition, as the absorbed moisture index, a sintered raw material sized for each particle size may be immersed in water for a long time, and a moisture content (immersion moisture) after dehydration may be used. For example, as apparent from FIG. 4 in which the ores A and B are verified, the intercept of the graph is a constant term independent of the particle diameter, and can be regarded as representing the absorbability of the ore itself.
The above chemical analysis values, pore volume, and absorbed moisture (immersion moisture) have a strong correlation with each other. When used, they are unified with any index, and the coefficient of the above equation (4) is recalculated by multiple regression. do it.

(B) “Adhesion moisture index” In the present invention, the value of the particle size distribution is used as the adhesion moisture index for the above-described reason based on FIG. As the particle size distribution, the mass ratio of fine powder is -1 mm, -0.5 mm, -0.125 mm, -0.063 mm, the mass ratio of each particle is +1 mm, +2 mm, +2 in the raw material. A mass ratio of 0.8 mm or +4.0 mm is used as the adhesion moisture index. In some cases, other sieve meshes or a mass ratio of a certain particle size section (for example, a ratio of 1 to 2.8 mm) may be used as the adhesion moisture index.

(C) Next, regarding the “chemical component” that is the correction index, particularly the Al ₂ O ₃ ratio and the SiO ₂ ratio,
Since the Al ₂ O ₃ ratio is an index of a kaolin-based mineral with remarkable absorbability, the analytical value in a particle size sample of 1 mm or less in the raw material is used. However, since the Al ₂ O ₃ ratio in the ore has a strong correlation between the −1 mm sample and the +1 mm sample, the analysis value of the iron ore itself may be used as it is.
Since the SiO ₂ ratio is an index that affects the adjustment of the slag component of the entire charged raw material, the analysis value of the particle size sample of the fine ore raw material may be used as it is.

(D) Next, another correction index, “wetability with water” (contact index with water),
The contact angle H of water is used as an index of wettability with water. The measurement of the contact angle H between the powder and water includes a method of actually measuring the contact angle when a fine water droplet is dropped on the cut surface of the ore, and a penetration method using the Hagen-Poiseuille equation below. In the measurement by the infiltration method, ore adjusted to a particle size of −1 mm is used as a sample, and the contact angle θ is calculated from the rising speed of the water surface rising the ore packed bed.

H = (φRγcos θ / 2η) ^0.5 · t ^0.5 (6)
Where each coefficient is
H: Height of water rise [m]
R: particle size [m],
t: time [sec],
γ: surface tension of water [N / m],
η: water viscosity [N / s · m ² ],
θ: Contact angle [°] between water and powder.
φ: Labyrinth factor

  The wettability of water has a strong correlation between the FeO concentration of the raw material and the contact angle. Since the contact angle increases as the FeO concentration increases, this FeO concentration may be measured and used as an index.

  In the method of the present invention, by using these indexes, the above-mentioned appropriate granulated water content [Wopt] is determined based on the estimation formula shown in the above formula (4), thereby determining the proper moisture concentration at the time of granulation. It can be estimated accurately.

In addition, the addition of moisture estimated in the above description is performed on the granulator, on the upstream side of the granulator, for example, on the conveyor that conveys from the yard, the yard to the raw material layer, in the raw material layer, and from the raw material layer to the granulator. Water may be added in advance at any one or a plurality of locations on the conveyor to be conveyed, or a combination of this advance addition and addition in a granulator may be used.
In this way, the sintered raw material adjusted to an appropriate granulation water content [Wopt] based on the formula (4) is put into a granulator and granulated, thereby producing high-strength pseudo particles (granulation and sintering). Can be produced.

Next, the production formula of the granulated sintered ore raw material in the case of using the estimation formula of the proper granulation moisture amount in the present invention and the estimation formula of the conventional method will be described in comparison.
FIG. 5 shows the flow of the sinter production process. In FIG. 7, 17 is a raw material mixing tank for stocking and cutting out raw materials, 18 is a belt conveyor for transporting the raw materials, and 19 is a drum mixer for granulating the sintered raw materials. The sintered raw material is cut out from the blending tank 17 onto the belt conveyor 18 at a predetermined blending ratio and conveyed to the drum mixer 19. The raw material charged into the drum mixer 19 is added with moisture at the upstream side of the drum, is tumbled and granulated to become pseudo particles, and is charged into a sintering pallet 22 of a sintering machine via a feed hopper 21. Sintered and then crushed by a crusher to become sintered ore.

  Prior to granulation work, the coefficient of equation (4) above is regressed from the chemical composition, absorbed moisture index, adhesion moisture index (particle size distribution), and wettability index of simple ore given appropriate granulation moisture in the experiment. Estimated by analysis. Tables 1 and 2 show the measurement results of chemical composition, particle size distribution, immersion moisture, wettability (contact angle), pore volume, and appropriate granulation moisture (Wopt) of each ore brand used in the operation.

  FIG. 6 shows the correlation between the estimated value of the proper granulated water content and the actual measured value of appropriate granulated water when estimated using the conventional method and FIG. 7 using the method of the present invention. In addition, the measured value of appropriate granulation moisture is the moisture content when the air permeability becomes the highest when granulation is performed while changing the moisture content.

In FIGS. 6 and 7, simple means that the raw material is a single brand, and blending means that the raw material is blending ore. When FIG. 6 and FIG. 7 are compared, the proper granulated water amount estimated by the conventional method has a correlation of about 94% with the actual measurement value, whereas the correlation is 98% when estimated by the method of the present invention. it was high.
In addition, when using blending ores with unknown brands, the difference between the estimated value and the measured value is large in the conventional method, and the correlation coefficient is 88%, whereas in the method of the present invention, the evaluation index is selected. The correlation coefficient was 96%.

  FIG. 8 shows changes in raw material air permeability during the operation period. Proper granulation water content was estimated using a conventional method, and the operation was continued by changing the blending of raw materials in the middle (mixing 1 → mixing 2). After that, with the same raw material blending (blending 2), the amount of granulated water was estimated by the method of the present invention and the operation was continued, and the raw material blending was changed (blending 2 → blending 3). An operation was performed to estimate the grain moisture content.

As a result, in the conventional method, the fluctuation range of the air permeability in the same raw material was about 15%, whereas the fluctuation range in the method of the present invention was suppressed to about 9%.
In addition, regarding the stable period of air permeability change at the time of blending change (brand change), the conventional method required about 2 days after the brand change, but the method of the present invention shortened it to about 1 day. .

  The technique for adjusting the appropriate water content during the production of the granulated and sintered raw material according to the present invention is effectively used even in the case where the proper granulated water content of other granulated materials other than the sintered raw material is estimated.

1 Orifice 2 Wind box 3 Test sintering pot (φ150mm)
4 Great 5 Pitot tube 6 Differential pressure gauge 7 Suction blower 8 Fine powder 9 Core particle 10 Pore 11 Ore particle 12 Water 13 Pseudo particle 14 Cross-linking water 15 Adhering water 16 Added water 17 Raw material hopper 18 Conveyor 19 Drum mixer 20 Conveyor 21 Feeding hopper 22 Sintered pallet 27 Sintered ore

Claims (2)

Appropriate for producing granulated sintered raw materials that are pseudo particles by adding moisture to the sintered raw materials containing iron ore, auxiliary raw materials, miscellaneous raw materials and solid fuel core particles and fine powders In the method of adjusting the amount of moisture,
Before water addition to the sintering material, moisture absorbed index sintered material, adhering moisture index, obtains a correction index Hazuki group index of these, suitability granulation water necessary for the pseudo-particles A method for adjusting an appropriate amount of water during the production of a granulated and sintered raw material, wherein the amount of water is determined so that the amount is estimated and the estimated appropriate amount of granulated water is obtained. 2. The granulated sintered raw material according to claim 1, wherein the iron ore in the sintered raw material contains at least part of a blending ore whose mixed ore type and mixing ratio are unknown. The proper moisture content adjustment method.

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