WO2018151024A1

WO2018151024A1 - Method for manufacturing sintered ore

Info

Publication number: WO2018151024A1
Application number: PCT/JP2018/004516
Authority: WO
Inventors: 俊輔野中; 祥和早坂; 直幸竹内; 義憲秋山; 友司岩見
Original assignee: Ｊｆｅスチール株式会社
Priority date: 2017-02-16
Filing date: 2018-02-09
Publication date: 2018-08-23
Also published as: TWI658148B; KR102290001B1; EP3550037A4; CN110325654A; JP6680369B2; JPWO2018151024A1; TW201833337A; EP3550037A1; KR20190109451A; PH12019501877A1

Abstract

Provided is a method for manufacturing sintered ore with which product sintered ore wherein reductions in quality are suppressed can be manufactured using sintered feedstock that includes iron ore and dust generated within a steel mill even when the component concentrations thereof vary. The manufacturing method for sintered ore, which is for manufacturing sintered ore by granulating sintered feedstock wherein at least feedstock including iron, feedstock including CaO, and an aggregating material are mixed and sintering the sintered feedstock in a sintering machine, has a measurement step for continuous measurement of at least one component concentration among the feedstock containing iron, sintered feedstock, and granulated sintered feedstock. Using the component concentration measured in the measurement step, at least one of the amount of feedstock containing CaO mixed in, the amount of aggregating material mixed in, the amount of water added, and the rate of progress of a pallet truck for the sintering machine is adjusted.

Description

Method for producing sintered ore

The present invention relates to a method for producing sintered ore that adjusts the blending amount of CaO-containing raw materials and the like in a sintered raw material. Specifically, the component concentration of the sintered raw material is continuously measured and the component concentration is used. The present invention relates to a method for producing sintered ore that adjusts the blending amount of CaO-containing raw materials.

In the blast furnace iron manufacturing method, currently, sintered ore, massive iron ore, pellets, and the like are mainly used as blast furnace raw materials as iron sources. Here, in addition to iron ore having a particle size of 10 mm or less, sintered ore is a source of miscellaneous iron such as various kinds of dust generated in the steelworks, raw materials containing CaO such as limestone, quicklime, and slag, serpentinite, and auxiliary material as SiO ₂ source or MgO source made of dolomite and smelting nickel slag, and a solid fuel (carbon material) is a condensation material made of coke breeze and anthracite, water was added in a drum mixer It is a kind of agglomerated mineral that is mixed, granulated and fired.

In recent years, the iron concentration of iron ore contained in the sintered raw material, which is the raw material of sintered ore, has decreased, and instead the concentration of gangue components such as SiO ₂ and Al ₂ O ₃ has increased. However, the component concentration of the iron ore produced becomes more unstable as the component concentration may differ from ship to ship at the time of import. As for various types of dust generated in steelworks, variations in the amount of generation and fluctuations in the components of the dust itself are large, and it is very difficult to manage the components as a sintering raw material.

The variation in the component concentration in the sintered raw material leads to the variation in the component concentration of the product sintered ore that is the product. For example, an increase in SiO ₂ is generally a factor that decreases the reducibility of the sintered ore, and an increase in Al ₂ O ₃ is a factor that generally decreases the strength of the sintered ore. For this reason, when the component of a sintering raw material remove | deviates from a plan value, the operation adjustment and mixing | blending adjustment for avoiding a quality fall are needed.

In general, the component concentration of sintered ore charged in a blast furnace is always controlled for reasons such as slag quality control. If the basicity rises or the alumina rises in the component concentration of the product sinter, the viscosity of the blast furnace slag rises, so it is necessary to raise the hot metal temperature in order to suppress the rise in the viscosity. Due to the increase in the viscosity of the blast furnace slag, the slag discharge at the lower part of the blast furnace deteriorates and the gas flow is hindered, so the air permeability is also deteriorated. For this reason, it is necessary to increase the amount of coke in order to increase the hot metal temperature and ensure the air permeability of the lower part of the blast furnace. As described above, when the component concentration of the blast furnace raw material greatly deviates from the target component concentration due to the variation in the component concentration of the product sintered ore, the blast furnace operation becomes unstable, and various measures are required.

In order to deal with such problems, efforts have been made to grasp the quality of sintered raw materials. For example, Patent Document 1 focuses on clay minerals contained in iron ores, and appropriately sets the content of clay minerals (kaolin: Al ₂ Si ₂ O ₅ (OH) ₄ ) in fine ores contained in iron ores. The technique which improves the granulation property of a sintering raw material by adjusting to the range is disclosed.

Patent Document 2 discloses a technique of measuring the FeO concentration of a product sintered ore and adjusting the coagulation material, granulated moisture, and exhaust air amount of the sintered raw material using the FeO concentration of the product sintered ore. Patent Document 3 also discloses a technique for measuring the FeO concentration of a product sintered ore and adjusting the amount of city gas blown in a sintering machine using the FeO concentration of the product sintered ore. Yes.

In Patent Document 4, a laser-type component measuring machine is installed on a sintering machine, and product baking is performed using the component concentration of the raw material charging layer surface layer charged in the pallet measured using the component measuring machine. A technique for estimating the component concentration of the ore and adjusting the blending amount of the sintering raw material using this is disclosed.

JP 2003-049227 A JP-A-57-149433 JP 2011-038735 A JP 60-262926 A

The technique disclosed in Patent Document 1 weighs a certain amount of iron ore sample and measures the component concentration of kaolin offline. In this way, it is possible to predict the component concentration of the sintered ore by measuring the components of the sintered raw material offline, but this is caused by fluctuations in the component concentration of the sintered raw material during the production of the sintered ore. It is difficult to cope with excess or deficiency of heat.

The techniques disclosed in Patent Document 2 and Patent Document 3 are techniques for continuously measuring the FeO concentration of the product sintered ore, and reflect the component analysis results of the product sintered ore to the adjustment of the blending amount of the sintering raw material. Therefore, it is difficult to quickly cope with fluctuations in the component concentration of the sintering raw material during sinter production.

The technique disclosed in Patent Document 4 estimates the component concentration of the product sintered ore from the component concentration of the raw material charging layer surface layer, but the state of the raw material charging layer depends on the sintering raw material charging device and the sintering material. Since it varies depending on the moisture content of the binding raw material, the component concentration of the surface layer of the raw material charging layer also varies. For this reason, the relationship between the component concentration of the charged layer surface layer and the component concentration of the product sintered ore is not uniform, and it is difficult to actually estimate the component concentration of the product sintered ore from the component concentration of the charged layer surface layer. It is.

The present invention has been made in view of such problems of the prior art, and the object thereof is to use a sintering raw material containing these even if the component concentration of dust generated in iron ore and ironworks fluctuates. Another object of the present invention is to provide a method for producing a sintered ore that can produce a product sintered ore with small fluctuations in the component concentration.

The features of the present invention that solve such problems are as follows.
(1) A method for producing a sintered ore comprising granulating a sintered raw material containing at least an iron-containing raw material, a CaO-containing raw material, and a coagulant, and producing a sintered ore by sintering with a sintering machine, The measurement step of continuously measuring at least one component concentration of the iron-containing raw material, the sintered raw material and the granulated sintered raw material, and the composition of the CaO-containing raw material using the component concentration measured in the measuring step And adjusting step of adjusting at least one of the amount, the blending amount of the coagulant, the added amount of water, and the traveling speed of the pallet carriage of the sintering machine.
(2) The sintered raw material is further mixed with an MgO-containing raw material, and in the adjustment step, the component concentration measured in the measuring step is used to mix the CaO-containing raw material and the MgO-containing raw material. The method for producing a sintered ore according to (1), wherein at least one of an amount, a blending amount of the coagulant, an amount of water added, and a traveling speed of a pallet carriage of a sintering machine is adjusted.
(3) Sintered raw material containing at least an iron-containing raw material, a CaO-containing raw material and a coagulating material is granulated, and the sintered raw material is sintered by supplying gaseous fuel and oxygen with a sintering machine. A method for producing a sintered ore to be produced, comprising: a measurement step of continuously measuring at least one component concentration of the iron-containing raw material, the sintered raw material, and the granulated sintered raw material, Using the measured component concentration, the amount of the CaO-containing raw material, the amount of the coagulant, the amount of water added, the speed of the pallet carriage of the sintering machine, the amount of gaseous fuel supplied, and the amount of oxygen supplied A method for producing a sintered ore, comprising: an adjustment step of performing at least one adjustment.
(4) The sintered raw material is further mixed with an MgO-containing raw material, and in the adjustment step, the compounding amount of the CaO-containing raw material and the mixing of the MgO-containing raw material are determined using the component concentrations measured in the measuring step. The amount, the blending amount of the coagulant, the addition amount of the water, the traveling speed of the pallet carriage of the sintering machine, the supply amount of gaseous fuel, and the supply amount of oxygen are adjusted. A method for producing sintered ore.
(5) In the measurement step, the concentration of one or more components of total CaO, SiO ₂ , MgO, Al ₂ O ₃ , FeO, C and moisture is measured, and any one of (1) to (4) The manufacturing method of the sintered ore as described.

By carrying out the method for producing a sintered ore of the present invention, a product in which the fluctuation of the component concentration is small and the deterioration of the quality is suppressed using a sintered raw material containing iron ore having a large fluctuation of the component concentration and dust generated in the ironworks. Sintered ore can be produced.

FIG. 1 is a schematic diagram illustrating an example of a sintered ore production apparatus 10 that can implement the method for producing a sintered ore according to the present embodiment. FIG. 2 is a graph showing the basicity of the sintering raw material of Invention Example 1 and the drop strength of the product sintered ore 72. FIG. 3 is a graph showing the basicity of the sintering raw material of Comparative Example 1 and the drop strength of the product sintered ore 72. FIG. 4 is a graph showing fluctuations in the production rate of the sintering machine of Invention Example 2, the carbon concentration of the sintering raw material, and the traveling speed of the pallet carriage. FIG. 5 is a graph showing fluctuations in the production rate of the sintering machine of Comparative Example 2, the carbon concentration of the sintering raw material, and the traveling speed of the pallet truck.

Hereinafter, the present invention will be described through embodiments of the invention. FIG. 1 is a schematic diagram illustrating an example of a sintered ore production apparatus 10 that can implement the method for producing a sintered ore according to the present embodiment. The iron-containing raw material 12 stored in the yard 11 is transported to the blending tank 22 by the transport conveyor 14. The iron-containing raw material 12 includes various brands of iron ore and dust generated in the steelworks.

The raw material supply unit 20 includes a plurality of

blending tanks

22, 24, 25, 26, and 28. The iron-containing raw material 12 is stored in the blending tank 22. The compounding tank 24 stores a CaO-containing raw material 16 containing limestone or quicklime, and the compounding tank 25 stores an MgO-containing raw material 17 containing dolomite, refined nickel slag, or the like. The blending tank 26 stores a coagulant 18 containing powdered coke and anthracite that have been crushed to a particle size of 1 mm or less using a rod mill. In the blending tank 28, returned ore (sintered ore sieving powder) having a particle size of 5 mm or less that has been sieved under the sintered ore is stored. A predetermined amount of each raw material is cut out from the mixing tanks 22 to 28 of the raw material supply unit 20, and these are mixed to become a sintered raw material. The sintered raw material is transported to the drum mixer 36 by the transport conveyor 30. The MgO-containing raw material 17 is an optional blending raw material, and may be blended with the sintering raw material or may not be blended.

An infrared analyzer 32 is provided on the conveyor 30 between the mixing tank 28 and the drum mixer 36. A measurement process is performed using the infrared analyzer 32. In the measurement step, the concentration of at least one component of total CaO, SiO ₂ , MgO, Al ₂ O ₃ , FeO, C and moisture contained in the sintered raw material is measured. Here, the moisture is a combination of the moisture adhering to the sintering material and the inherent moisture that is contained in the material in a constant temperature state and is expelled by heating.
The infrared analyzer 32 irradiates the sintering material with infrared rays having a wavelength in the range of 0.5 to 50.0 μm, and receives reflected light from the sintering material. Since each molecular vibration of total CaO, SiO ₂ , MgO, Al ₂ O ₃ , FeO, and water contained in the sintering raw material absorbs the intrinsic wavelength component of the irradiated infrared, these components are reflected in the reflected infrared. A unique wavelength component is added. A crystal structure of a monoatomic molecule such as carbon (C) also starts to vibrate when irradiated with infrared rays, and gives a unique wavelength component to reflected infrared rays. For this reason, the component concentration of total CaO, SiO ₂ , MgO, Al ₂ O ₃ , FeO, C and moisture in the sintering raw material can be measured by analyzing the irradiated infrared rays and the reflected infrared rays. Total CaO is obtained by converting Ca in all compounds having Ca and O such as CaO, CaCO ₃ , Ca (OH) _2, and Fe ₂ CaO ₄ into CaO.

The infrared analyzer 32 irradiates infrared rays having a wavelength of 20 or more at a frequency of 128 times per minute, for example, and receives the reflected light reflected by the sintering material. Thus, since infrared rays can be irradiated in a short time, the infrared analyzer 32 can continuously measure the component concentration of the sintering raw material conveyed on the conveyor 30 on-line. The infrared analyzer 32 is an example of an analyzer for measuring the component concentration of the sintering raw material. Instead of the infrared analyzer 32, a laser analyzer that irradiates the measurement target with a laser, and a neutron analysis that irradiates the measurement target with a neutron. You may use the meter or the microwave analyzer which irradiates a measuring object with a microwave.

The sintered raw material conveyed to the drum mixer 36 is put into the drum mixer 36, and an appropriate amount of water 34 is added, and granulated into, for example, pseudo particles having an average particle diameter of 3.0 to 6.0 mm. The granulated sintered raw material is conveyed to the sintered raw material supply device of the sintering machine 40 by the conveying conveyor 38. The drum mixer 36 is an example of a granulating apparatus that granulates a sintered raw material. There may be a plurality of drum mixers 36, and a pelletizer granulator may be used instead of the drum mixer 36. Both the drum mixer 36 and the pelletizer granulator may be used, and a high-speed stirrer may be installed upstream of the drum mixer 36 to stir the sintered raw material. In the present embodiment, the average particle size is an arithmetic average particle size, and Σ (Vi × di) (where Vi is the abundance ratio of particles in the i-th particle size range, and di is the i-th particle size) It is a particle size defined in the above.

Using the component concentration of the sintered raw material measured in the measurement step, the blending amount of the CaO-containing raw material 16, the blending amount of the coagulant 18, and the water added by the drum mixer 36 so as to reach a predetermined target value. An adjustment step of adjusting at least one of the addition amounts of 34 is performed. The predetermined target value is, for example, the basicity (CaO / SiO ₂ ) of the sintering raw material, the carbon concentration, the MgO concentration, the moisture concentration, the Al ₂ O ₃ concentration of the sintering raw material, or the amount of heat during sintering. These target values may be determined in advance using past production results of sintered ore and the like. When the MgO-containing raw material 17 is blended, the blending amount of the MgO-containing raw material 17 may be adjusted in the adjusting step using the component concentration of the sintered raw material measured in the measuring step.

In the present embodiment, the component concentration measurement frequency by the infrared analyzer 32 is 128 times per minute, the average value of the 128 component concentrations is calculated once per minute, and the calculated average value of the component concentrations is calculated. Was used to adjust the blending amount of the blast furnace raw material every minute.

Even if the component concentration of the gangue component of the iron ore fluctuates by this adjustment step, for example, the basicity (CaO / SiO) of the sintering raw material is determined using the component concentration of the sintering raw material measured in the measurement step. _By controlling the blending amount of the CaO-containing raw material 16 so that ₂ ) becomes a predetermined target value, fluctuations in the basicity (CaO / SiO ₂ ) of the sintered raw material are reduced.

Even if the carbon concentration of the dust generated in the steel works fluctuates, the carbon concentration of the sintered raw material measured in the measurement process is used so that the carbon concentration of the sintered raw material becomes a predetermined target value. The feedback control of the blending amount of 18 reduces the variation in the carbon concentration in the sintering raw material.

Even if the moisture concentration of the iron ore and the dust generated in the ironworks fluctuates, the water added by the drum mixer 36 from the moisture concentration of the sintered raw material measured in the measurement process and the predetermined moisture concentration as a target. It is possible to perform feedforward control for determining the amount of addition of 34. Then, the amount of water 34 adjusted by the control is added by the drum mixer 36, whereby the moisture concentration of the sintered raw material can be adjusted to the target moisture concentration.

The sintering machine 40 is, for example, a downward suction type dwyroid sintering machine. The sintering machine 40 includes a sintering raw material supply device 42, an endless moving pallet truck 44, an ignition furnace 46, a gaseous fuel supply device 47, and a wind box 48. Sintered raw material is charged into the pallet truck 44 from the sintered raw material supply device 42 to form a charged layer of the sintered raw material. The charge layer is ignited in an ignition furnace 46. By sucking air through the wind box 48, the charging layer takes in the gaseous fuel and oxygen supplied from the gaseous fuel supply device 47 provided above into the charging layer, and condenses with the gaseous fuel in the charging layer. While burning the material 18, the combustion / melting zone in the charging layer is moved below the charging layer. Thereby, the charging layer is sintered to form a sintered cake. In this embodiment, the gaseous fuel is selected from blast furnace gas, coke oven gas, blast furnace / coke oven mixed gas, converter gas, city gas, natural gas, methane gas, ethane gas, propane gas, shale gas, and mixed gas thereof. Any flammable gas.

Using the component concentration of the sintering raw material measured in the measurement process, the traveling speed of the pallet truck 44 in the sintering machine 40, the supply amount of gaseous fuel on the sintering machine, and the supply amount of oxygen on the sintering machine At least one of the adjustments may be performed.

The sintered cake is crushed by the crusher 50 and made into sintered ore. The sintered ore crushed by the crusher 50 is cooled by the cooler 60. The sintered ore cooled by the cooler 60 is sieved by a sieving device 70 having a plurality of sieves, and is sieved into a product sintered ore 72 having a particle size of more than 5 mm and a return ore 74 having a particle size of 5 mm or less. Is done. The sintered product ore 72 is transported to the blast furnace 80 by the transport conveyor 76 and charged into the blast furnace as a blast furnace raw material. On the other hand, the return ore 74 is transported to the blending tank 28 of the raw material supply unit 20 by the transport conveyor 78. Since the sintered ore 72 crushed by the crusher 50 is cooled and sieved, the product sintered ore 72 has the same components as the sintered ore 72 and the sintered ore crushed by the crusher 50. Concentration of sintered ore. In this embodiment, the particle size of the product sintered ore 72 and the particle size of the return ore 74 mean a particle size that is sieved by a sieve. For example, a particle size of more than 5 mm means using a sieve having an opening of 5 mm. The particle diameter is sieved on the sieve, and the particle diameter of 5 mm or less is the grain diameter sieved under the sieve using a sieve having an opening of 5 mm. Each value of the particle size of the product sintered ore 72 and the return ore 74 is an example to the last, and is not limited to this value.

Thus, in the manufacturing method of the sintered ore which concerns on this embodiment, it mix | blends the CaO containing raw material 16 so that it may become a predetermined target value using the component density | concentration measured with the infrared analyzer 32 in a measurement process. An adjustment step of adjusting at least one of the amount, the blending amount of the coagulant 18 and the amount of water 34 added by the drum mixer 36 is performed. Thereby, the fluctuation | variation of the component density | concentration of a sintering raw material becomes small, and the fluctuation | variation of the component density | concentration of the product sintered ore 72 manufactured using the said sintering raw material also becomes small, As a result, the quality deterioration of the product sintering ore 72 Can be suppressed.

For example, using the CaO and SiO ₂ concentrations measured in the measuring step in the adjustment step, the basicity of the sintered raw material (CaO / SiO ₂ ) is adjusted to a predetermined target value. You may adjust a compounding quantity. As a result, even if iron ore having a large variation in the component concentration of the gangue component is used, the variation in the basicity (CaO / SiO ₂ ) of the sintering raw material is reduced, and the product ware manufactured using the sintering raw material is reduced. The fluctuation of the basicity of the ore 72 is also reduced, and the product sintered ore 72 with stable strength can be manufactured. It is possible to contribute to stable operation of the blast furnace by using the sintered product ore 72 having a small basicity variation as a blast furnace raw material.

When the variation of the carbon concentration of the sintering raw material is large, the variation of the calorific value at the time of sintering becomes large, and thereby the variation of the FeO concentration of the product sintered ore 72 also becomes large. Thus, when the fluctuation | variation of FeO density | concentration becomes large, the compounding quantity of the condensing material 18 and the supply of gaseous fuel on a sintering machine so that the calorie | heat amount at the time of sintering may become a predetermined target value in an adjustment process. At least one of the amount and the supply amount of oxygen on the sintering machine may be adjusted. Thereby, the fluctuation | variation of the calorie | heat amount at the time of sintering becomes small, and the fluctuation | variation of the FeO density | concentration of the product sintered ore 72 also becomes small.

The amount of water 34 added by the drum mixer 36 may be adjusted using the method for producing sintered ore according to the present embodiment. By adjusting the amount of water 34 added so as to be a predetermined target value of the moisture concentration, fluctuations in the moisture concentration of the sintering raw material are reduced, and fluctuations in the amount of heat during sintering are further reduced. Thereby, the fluctuation | variation of the FeO density | concentration of the product sintered ore 72 becomes still smaller.

If the FeO concentration of the product sintered ore 72 varies and the FeO concentration increases, the reducibility of the blast furnace raw material deteriorates. When the reducibility of the blast furnace raw material deteriorates, indirect reduction, which is an exothermic reaction, decreases, direct reduction, which is an endothermic reaction, increases, and the inside of the blast furnace becomes short of heat. In order to eliminate this heat shortage, the reducing material is further charged into the blast furnace, and the coke ratio in blast furnace operation increases. For this reason, the increase in the coke ratio of the blast furnace operation can be suppressed by controlling the FeO concentration of the product sintered ore 72 to the target component concentration.

When the amount of heat during sintering increases and the temperature of the sintered cake increases, the cooler 60 is overloaded. For this reason, when the increase in the carbon concentration of the sintering raw material is confirmed in the measurement process, the traveling speed of the pallet truck 44 of the sintering machine is reduced when the sintering raw material is sintered by the sintering machine 40. May be. Thereby, the load of the cooler 60 can be reduced. In the measurement process of the present embodiment, since the component concentration of the sintering raw material is continuously measured online, it is possible to grasp a sudden increase in carbon concentration. By reducing the traveling speed of the pallet carriage 44 of the sintering machine according to the increase in the carbon concentration, it is possible to prevent the equipment from being damaged due to the temperature increase of the sintered cake.

When the MgO-containing raw material 17 is blended with the sintered raw material, the MgO-containing raw material 17 is set to a predetermined target value of the MgO concentration using the MgO concentration measured by the infrared analyzer 32 in the measurement process. The blending amount of may be adjusted. Thereby, the fluctuation | variation of the component density | concentration of MgO of the product sintered ore 72 also becomes small. The MgO component in the product sintered ore 72 has an effect of improving the softening and melting property by increasing the melting point. For this reason, the effect of improving the softening and melting property can be obtained by reducing the fluctuation of the MgO component concentration of the product sintered ore 72, which can contribute to the stable operation of the blast furnace.

In this embodiment, the example which manufactures a sintered ore using the sintering machine 40 which has the gaseous fuel supply apparatus 47 was shown, However, not only the sintering machine 40 which has the gaseous fuel supply apparatus 47 but gaseous fuel supply apparatus Even a sinter production apparatus having a sintering machine without 47 can be applied. When a sintering machine that does not have the gaseous fuel supply device 47 is used, the component concentration measured in the measurement step is used, the compounding amount of the CaO-containing raw material 16, the compounding amount of the coagulant 18, and the additive amount of water 34. And adjusting at least one of the traveling speeds of the pallet carriage 44 of the sintering machine. That is, in the present embodiment, the supply of gaseous fuel and oxygen in the sintering machine 40 may be performed as necessary, and the adjustment of the supply amount of gaseous fuel and / or the supply amount of oxygen in the adjustment step is also necessary. Just do it.

In this embodiment, although the infrared analyzer 32 was provided in the conveyance conveyor 30 between the mixing tank 28 and the drum mixer 36, the example which measures the component density | concentration of a sintering raw material was shown, It is not restricted to this. One or more components of total CaO, SiO ₂ , MgO, Al ₂ O ₃ , FeO, C and moisture contained in the iron-containing raw material 12 which is provided with the infrared analyzer 32 on the conveyor 14 and is conveyed to the blending tank 22 The concentration may be measured, and an infrared analyzer 32 is provided on the transport conveyor 30 between the blending tank 22 and the blending tank 24, and the total CaO and SiO ₂ contained in the iron-containing raw material 12 transported from the blending tank 22. One or more component concentrations of MgO, Al ₂ O ₃ , FeO, C, and moisture may be measured. Factors causing fluctuations in the component concentration of the sintered raw material are greatly affected by fluctuations in the component concentrations of various brands of iron ore and dust generated in the ironworks contained in the iron-containing raw material 12 stored in the yard 11. For this reason, the infrared analyzer 32 is provided in the conveyance conveyor 14, the component density | concentration of the iron containing raw material 12 is measured, and the mixing | blending of the CaO containing raw material 16 is used using the said measured value and the component density | concentration of the target sintering raw material. The feedforward control that determines at least one of the amount, the blending amount of the coagulant 18 and the addition amount of the water 34 can be performed, whereby the concentration fluctuation of each component of the sintered raw material can be reduced. An infrared analyzer 32 is provided on the conveyor 14 to measure the component concentration of the iron-containing raw material 12, and the measured value is used to advance the pallet carriage 44 of the sintering machine, the gaseous fuel on the sintering machine, and / or By adjusting the supply amount of oxygen, adverse effects due to fluctuations in the amount of heat during sintering can be suppressed.

The infrared analyzer 32 is provided on the conveyor 38, and the total CaO, SiO ₂ , MgO, Al ₂ O ₃ , FeO, C, and moisture contained in the granulated sintered raw material conveyed to the sintering machine 40 You may measure the component density | concentration of a seed | species or more. Since the granulated sintered raw material is uniformly mixed by the drum mixer 36 and each raw material is not segregated, the component concentration of the sintered raw material can be measured with high accuracy. Then, by using at least one of the blending amount of the CaO-containing raw material 16, the blending amount of the coagulant 18, and the addition amount of water 34 using the component concentration, feedback control is performed to reduce the concentration fluctuation of each component of the sintering raw material. it can. Furthermore, the traveling speed of the pallet carriage 44 of the sintering machine and the supply amount of gaseous fuel and / or oxygen may be adjusted by using the measured values, thereby suppressing adverse effects due to fluctuations in the amount of heat during sintering. .

In the present embodiment, an example has been shown in which each raw material is cut out from the mixing tanks 22 to 28 of the raw material supply unit 20 and used as a sintered raw material by the conveyor 30 and a sintered raw material granulated by the drum mixer 36. Not limited to. For example, a sintered raw material in which the iron-containing raw material 12, the CaO-containing raw material 16 and the return mineral 74 are blended is put into the drum mixer 36, and water is added to the sintered raw material for granulation. May be used as the granulated sintered raw material. In this case, the concentration of at least one of the iron-containing raw material 12 and the sintered raw material is measured using the infrared analyzer 32, and the blended amount of the CaO-containing raw material 16 and the coagulant 18 are measured using the measured values. At least one of the mixing amount, the addition amount of water 34, the traveling speed of the pallet carriage 44 of the sintering machine, the supply amount of gaseous fuel, and the supply amount of oxygen.

A sintered raw material in which a part of the iron-containing raw material 12, the CaO-containing raw material 16, the return mineral 74, and the coagulating material 18 is mixed is put into the drum mixer 36, and water is added to the sintered raw material for granulation. By putting the remainder of the coagulation material 18 in the latter half of the time, the carbonaceous material exterior particles in which the coagulation material 18 is present in the surface layer of the granulated sintering material may be used as the granulated sintering material. Powdered coke and anthracite are used as the coagulant added in the latter half of the granulation by adding water to the coagulation raw material.

In the case of using a plurality of drum mixers 36 and using carbonaceous material-coated particles in which the coagulant 18 is present on the surface layer, a part or all of the coagulant 18 is introduced into the latter half of the last drum mixer 36. The carbonaceous material outer particles having the coagulant 18 existing on the surface layer may be granulated by introducing the sintered raw material into the drum mixer 36 by the method described above. Further, when a plurality of drum mixers 36 are provided, the water added to the sintering raw material may be all water added by the first drum mixer 36, or a part of the water may be added by the first drum mixer 36. And the remainder may be added by another drum mixer 36.

In the present embodiment, an example has been shown in which each raw material is cut out from the mixing tanks 22 to 28 of the raw material supply unit 20 and used as a sintered raw material by the conveyor 30 and a sintered raw material granulated by the drum mixer 36. Not limited to. For example, a sintered raw material containing the iron-containing raw material 12 and the return mineral 74 is charged into the drum mixer 36, and water is added to the sintered raw material for granulation. The granulated particles in which the CaO-containing raw material 16 or the CaO-containing raw material 16 and the coagulant 18 are present on the surface layer may be used as the granulated sintered raw material by introducing the No. 16 and the coagulant 18. In this case, the concentration of at least one of the iron-containing raw material 12 and the sintered raw material is measured using the infrared analyzer 32, and the blended amount of the CaO-containing raw material 16 and the coagulant 18 are measured using the measured values. At least one of the mixing amount of water, the addition amount of water 34, the traveling speed of the pallet carriage 44 of the sintering machine, the supply amount of gaseous fuel on the sintering machine, and the supply amount of oxygen on the sintering machine To do.

A sintered raw material in which iron-containing raw material 12, return mineral 74, a part of CaO-containing raw material 16 or a part of CaO-containing raw material 16 and a part of aggregating material 18 are mixed is put into a drum mixer 36, and used as a raw material for sintering. By adding water and granulating, the CaO-containing raw material 16 and the coagulant 18 are added to the surface layer of the granulated sintered raw material by blending the remainder of the CaO-containing raw material 16 and the remainder of the coagulating material 18 in the latter half of the granulation. The existing granulated particles may be used as a granulated sintering raw material.

In the case where a plurality of drum mixers 36 are provided and the granulated particles having the CaO-containing raw material 16 or the CaO-containing raw material 16 and the coagulant 18 existing on the surface layer, some or all of the CaO-containing raw material 16 and the coagulant 18 are added to the last half of the final drum mixer 36, and the sintered raw material is input to the drum mixer 36 by the method described above, whereby the granulated particles in which the CaO-containing raw material 16 and the coagulant 18 are present on the surface layer. May be granulated.

In the present embodiment, an example has been described in which each raw material is cut out from the mixing tanks 22 to 28 of the raw material supply unit 20 and is used as a sintered raw material by the transport conveyor 30, but the present invention is not limited thereto. For example, a part of each raw material cut out from the mixing tanks 22 to 28 of the raw material supply unit 20 is directly transported to the drum mixer 36 by the transport conveyor 30 and the remaining part is transported to the high-speed stirring device by a transport conveyor different from the transport conveyor 30. And stir. Thereafter, the remaining portion may be granulated with a granulator such as a drum mixer or a pelletizer, and if necessary, dried with a dryer and then put into the conveyor 30 or conveyor 38. The remaining portion may be directly fed to the conveyor 30 without being granulated by a granulator such as a drum mixer or a pelletizer after being stirred. Further, a crushing step and / or a sieving step may be provided before stirring with the high-speed stirring device. When there are a plurality of drum mixers 36, the drum mixers 36 may be put on a conveyor between any drum mixers.

In the present embodiment, an example in which the infrared analyzer 32 in the measurement process is provided on the transport conveyor 30 between the blending tank 28 and the drum mixer 36 is shown, but the present invention is not limited thereto. For example, the infrared analyzer 32 is connected to the conveyor 14 between the yard 11 and the most incoming mixing tank 22, the conveyor 30 between the mixing tank 22 and the mixing tank 24, or the drum mixer 36 and the sintering machine 40. You may provide in the conveyance conveyor 38 in between. However, when granulated particles in which the coagulant 18 or the CaO-containing raw material 16 and the coagulant 18 are present on the surface layer are used, the surface layer components may affect the measurement of the component concentration. More preferably, an infrared analyzer 32 is provided on the conveyor 30 between the blending tank 22 and the blending tank 24 or on the conveyor 30 between the blending tank 28 and the drum mixer 36.

The number of infrared analyzers 32 in the measurement process is not limited to one, and a plurality of infrared analyzers 32 may be provided. The transport conveyor 14, the transport conveyor 30 between the blending tank 22 and the blending tank 24, and the transport conveyor 30 between the blending tank 28 and the drum mixer 36. Two or more infrared analyzers may be provided on the conveyor 38. Using a plurality of infrared analyzers, two or more component concentrations of the sintered raw material, the iron-containing raw material 12 and the granulated sintered raw material are measured, and using the measured values, the blending amount of the CaO-containing raw material 16 At least one of the blending amount of the coagulant 18, the amount of water 34 added, the traveling speed of the pallet carriage 44 of the sintering machine, the supply amount of gaseous fuel on the sintering machine, and the supply amount of oxygen on the sintering machine You may adjust one.

Example 1
Inventive Example 1 and Comparative Example 1 were both manufactured using the sintered ore manufacturing apparatus 10 shown in FIG. In Invention Example 1, the component concentration of the sintering raw material is continuously measured using an infrared analyzer 32 provided on the conveyor 30, and the basicity (CaO / SiO ₂ ) of the sintering raw material is measured using the measured component concentration. The product sintered ore was manufactured for 36 hours while adjusting the blending amount of the CaO-containing raw material 16 so that the basicity (CaO / SiO ₂ ) becomes the target. On the other hand, in Comparative Example 1, the component concentration of the sintering raw material is measured every two hours offline instead of continuous measurement, and the basicity (CaO / SiO ₂ ) of the sintering raw material is set as a target using the measured component concentration. The product sintered ore was produced for 36 hours while adjusting the blending amount of the CaO-containing raw material 16 so that the basicity (CaO / SiO ₂ ) was obtained.

FIG. 2 is a graph showing the basicity of the sintering raw material of Invention Example 1 and the drop strength of the product sintered ore. FIG. 3 is a graph showing the basicity of the sintered raw material of Comparative Example 1 and the drop strength of the product sintered ore. The basicity shown in FIGS. 2A and 3A is obtained by dividing the total CaO concentration in the sintering raw material by the SiO ₂ concentration. The drop strengths shown in FIGS. 2B and 3B are strengths measured using a drop strength test method defined in JIS M 8711.

As shown in FIGS. 2 (a) and 2 (b), in Invention Example 1, the deviation of the basicity of the sintered raw material from the target value was reduced, and the fluctuation in the drop strength of the product sintered ore was also reduced. In Invention Example 1, the component concentration of the sintering raw material is continuously measured. For this reason, even if the component concentration suddenly fluctuates, the amount of the CaO-containing raw material 16 can be adjusted at an early stage so that the fluctuation of the component concentration is detected early and the component concentration becomes the target value. . Thereby, in Invention Example 1, the deviation of the basicity of the sintering raw material from the target value and the fluctuation of the basicity could be reduced, and the fluctuation of the drop strength of the product sintered ore could also be reduced.

On the other hand, as shown in FIGS. 3 (a) and 3 (b), in Comparative Example 1, the basicity of the sintered raw material greatly fluctuates with respect to the target value, and the drop strength of the product sintered ore greatly fluctuates. A low product sinter was produced. When the drop strength of the product sinter becomes low, the product sinter is easily crushed by the impact at the time of transportation and charging to the blast furnace, and the particle size of the product sinter varies. Variation in the particle size of the sintered product ore is not preferable because it causes disturbance of the raw material charging distribution in the blast furnace.

From these results, it was confirmed that by using the production method of Invention Example 1, it is possible to produce a product sinter with small fluctuations in the component concentration and drop strength of the product sinter.
(Example 2)
In both Invention Example 2 and Comparative Example 2, a product sinter was produced using the sinter production apparatus 10 shown in FIG. In Invention Example 2, the carbon concentration of the sintering raw material is continuously measured using the infrared analyzer 32 provided on the transport conveyor 30, and the carbon concentration of the sintering raw material is adjusted to the target concentration using the measured carbon concentration. The product sintered ore was produced for 36 hours while adjusting the blending amount of the coagulant 18 so as to be. On the other hand, in Comparative Example 2, the carbon concentration of the sintering raw material is measured every four hours offline, not continuously, and the measured carbon concentration is used so that the carbon concentration of the sintering raw material becomes a target concentration. The product sintered ore was produced for 36 hours while adjusting the blending amount of the coagulant 18. The target value of the carbon concentration of the sintering raw material is calculated using the components of the sintering raw material to calculate the sintering temperature at which the liquid phase ratio of the sintering raw material during sintering is within a preferable range, It was determined based on the amount of carbon that could be raised to the sintering temperature. In both Invention Example 2 and Comparative Example 2, the sintered raw material was changed to a sintered raw material with a high carbon concentration during the production of the product sintered ore, and then the production of the product sintered ore was continued by replacing the sintered raw material. did.

FIG. 4 is a graph showing fluctuations in the production rate of the sintering machine of Invention Example 2, the carbon concentration of the sintering raw material, and the traveling speed of the pallet carriage. FIG. 5 is a graph showing fluctuations in the production rate of the sintering machine of Comparative Example 2, the carbon concentration of the sintering raw material, and the traveling speed of the pallet truck. FIG. 4A and FIG. 5A show fluctuations in the production rate (t / (h × m ² )) of the sintering machine. The production rate (t / (h × m ² )) of the sintering machine is obtained by dividing the mass (t) of the sintered cake per hour produced by the sintering machine by the area (m ² ) of the pallet truck. This is a calculated value. FIG. 4B and FIG. 5B show fluctuations in the carbon concentration (mass%) of the sintering raw material. 4 (c) and 5 (c) show fluctuations in the traveling speed (m / min) of the pallet truck. 4 and 5, the portion surrounded by a broken line frame indicates a “raw material change period” in which the raw material is changed to a sintered raw material having a high carbon concentration.

In Invention Example 2, the carbon concentration of the sintering raw material is continuously measured, and the blending amount of the coagulant 18 is adjusted so that the carbon concentration becomes a target value. Thus, since the component concentration of the sintering raw material is continuously measured, an increase in the carbon concentration can be detected at the initial stage of the raw material change period, and the carbon concentration of the sintering raw material is set to the target carbon concentration using the concentration. Thus, the blending amount of the coagulant 18 was adjusted at an early stage. Thereby, as shown in FIG.4 (b), the raise of the carbon concentration of a sintering raw material is suppressed, and as shown in FIG.4 (c), a sintered ore is manufactured, without reducing the advancing speed of a pallet truck. As a result, as shown in FIG. 4A, the production rate of the sintering machine 40 was not greatly reduced.

On the other hand, in Comparative Example 2, since the carbon concentration of the sintering raw material is not continuously measured, detection of an increase in the carbon concentration of the sintering raw material is delayed. For this reason, as shown in FIG.5 (b), the carbon concentration of a sintering raw material has raised large. If the temperature of the sintered cake becomes too high due to an increase in the carbon concentration, the cooler 60 is overloaded. Therefore, it is necessary to reduce the traveling speed of the pallet truck to reduce the load on the cooler 60. For this reason, as shown in FIG.5 (c), the advancing speed of the pallet truck was reduced, As a result, the production rate of the sintering machine 40 fell significantly as shown in Fig.5 (a).

In this way, by using the manufacturing method of Invention Example 2, even if the carbon concentration of the sintering raw material fluctuates, the change in the carbon concentration is detected at an early stage, and the condensation occurs at an early stage in response to the change in the carbon concentration. The amount of the material 18 can be adjusted. Thereby, the fluctuation of the carbon concentration of the sintering raw material is reduced, and the fluctuation of the calorie during the production of the sintered ore is also reduced. As a result, the temperature rise of the product sintered ore is suppressed and the production rate of the sintering machine 40 is reduced. It was confirmed that the decrease was suppressed.

DESCRIPTION OF SYMBOLS 10 Sinter production apparatus 11 Yards 12 Iron containing raw material 14 Conveyor 16 CaO containing raw material 17 MgO containing raw material 18 Condensed material 20 Raw material supply part 22 Compounding tank 24 Compounding tank 25 Compounding tank 26 Compounding tank 28 Compounding tank 30 Conveying conveyor 32 Infrared rays Analyzer 34 Water 36 Drum mixer 38 Conveyor 40 Sintering machine 42 Sintering raw material supply device 44 Pallet cart 46 Ignition furnace 47 Gaseous fuel supply device 48 Wind box 50 Crusher 60 Cooling device 70 Sieving device 72 Product sintered ore 74 Returning 76 Transport conveyor 78 Transport conveyor 80 Blast furnace

Claims

A method for producing a sintered ore in which at least an iron-containing raw material, a CaO-containing raw material and a coagulating material are mixed with water, granulated and sintered with a sintering machine to produce a sintered ore. ,
A measurement step of continuously measuring the concentration of at least one of the iron-containing raw material, the sintered raw material, and the granulated sintered raw material;
Using the component concentration measured in the measurement step, at least one adjustment among the blending amount of the CaO-containing raw material, the blending amount of the coagulant, the addition amount of the water, and the traveling speed of the pallet carriage of the sintering machine An adjustment process to perform
A method for producing sintered ore.
The sintered raw material is further blended with an MgO-containing raw material,
In the adjustment step, using the component concentration measured in the measurement step, the blending amount of the CaO-containing raw material, the blending amount of the MgO-containing raw material, the blending amount of the coagulant, the addition amount of the water, and the sintering The manufacturing method of the sintered ore of Claim 1 which adjusts at least 1 among the advancing speeds of the pallet truck of a machine.
At least iron-containing raw material, CaO-containing raw material, and a sintering raw material mixed with water are granulated by adding water, and the sintering raw material is sintered and sintered while supplying gaseous fuel and oxygen with a sintering machine. A method for producing a sintered ore for producing ore,
A measurement step of continuously measuring the concentration of at least one of the iron-containing raw material, the sintered raw material, and the granulated sintered raw material;
Using the component concentration measured in the measurement step, the blending amount of the CaO-containing raw material, the blending amount of the coagulant, the amount of water added, the traveling speed of the pallet carriage of the sintering machine, the supply of the gaseous fuel An adjustment step of adjusting at least one of the amount and the supply amount of oxygen;
A method for producing sintered ore.
The sintered raw material is further blended with an MgO-containing raw material,
In the adjustment step, using the component concentration measured in the measurement step, the blending amount of the CaO-containing raw material, the blending amount of the MgO-containing raw material, the blending amount of the coagulant, the addition amount of the water, and the sintering The method for producing a sintered ore according to claim 3, wherein at least one of a traveling speed of a pallet truck of the machine, a supply amount of the gaseous fuel, and a supply amount of the oxygen is adjusted.
5. The firing according to claim 1, wherein in the measuring step, the concentration of one or more components of total CaO, SiO 2 , MgO, Al 2 O 3 , FeO, C and moisture is measured. Production method of ore.