JP6665972B2 - Sinter production method - Google Patents

Description

  The present invention relates to a method for producing a sintered ore, specifically, a method for measuring a component concentration of a sintered ore and adjusting a traveling speed of a pallet truck using the component concentration. About.

In the blast furnace ironmaking method, iron-containing raw materials such as sintered ore, lump ore, and pellets are mainly used as blast furnace raw materials as iron sources. Here, sinter is used as a source of iron ore having a particle size of 10 mm or less and various iron sources such as dust generated in steel works, a CaO-containing raw material such as limestone, quicklime, and steelmaking slag, and a coke fine or anthracite. Using a drum mixer, a sintering raw material obtained by mixing a coagulant, an MgO-containing raw material such as smelted nickel slag, dolomite, and serpentine as an optional mixing raw material and a SiO ₂ -containing raw material such as smelted nickel slag and silica stone is mixed with a drum mixer. Is a kind of agglomerate that is mixed, granulated, and fired while adding lime.

In recent years, the iron concentration of iron ore contained in the sintering raw material that is the raw material of the sinter has decreased, and instead the concentration of gangue components such as SiO ₂ and Al ₂ O ₃ has increased. In addition, the concentration of components in iron ore produced is so unstable that the concentration of components may differ from ship to ship at the time of import.

  Various kinds of dust generated in a steel mill have a large variation in the amount of generation and a large amount of variation in the contained carbon. When the amount of carbon contained in the sintering material fluctuates greatly, the reaction temperature of sintering fluctuates.

  Fluctuations in the sintering reaction temperature lead to fluctuations in the quality of the product sinter (hereinafter simply referred to as “sinter”), which greatly affects the quality of the sinter. For example, when the calorific value is excessive, the sintering reaction temperature rises, a vitreous low-strength structure is formed in the sinter, or the magnetite structure increases, and the reducibility decreases. Quality of the product. On the other hand, when the calorific value is insufficient, the reaction temperature of the sintering decreases, and there is a possibility that the sintering reaction does not occur in the first place, and in that case, the sintered ore itself cannot be obtained. Therefore, controlling the reaction temperature of sintering is indispensable for maintaining stable sinter quality.

  However, it is very difficult to continuously measure the sintering reaction temperature. For this reason, it is common to estimate the reaction temperature of sintering and analyze the calorific value by analyzing the components of the sinter. Specifically, the FeO concentration and the residual C concentration of the sinter are measured. In the sintering reaction, the sinter ore hematite undergoes thermal dissociation into magnetite with increasing temperature. As the temperature decreases after the reaction, the magnetite changes from hematite to hematite again, but the entire amount of thermally dissociated magnetite does not return to hematite. Therefore, when the sintering reaction temperature is high, a large amount of magnetite remains in the sintered ore. Since magnetite contains divalent Fe, the FeO concentration of the sinter serves as an index indicating the reaction temperature of sintering. Since C remaining in the sinter indicates that it was not used as a heat source in the sintering reaction, if the concentration of C remaining in the sinter is high, shortage of heat during the sintering reaction is suspected.

  Conventionally, the measurement of the components of the sinter and the adjustment of the calorific value of the sintering reaction have been performed. For example, Patent Literature 1 discloses a technique in which the FeO concentration of a sinter is measured, and the coagulant, granulated moisture, and exhaust air volume of a sintering raw material are adjusted using the FeO concentration of the sinter. Patent Literature 2 discloses a technique in which the FeO concentration of a sinter is measured, and the amount of city gas blown in a sintering machine is adjusted using the FeO concentration of the sinter.

  Further, in Patent Document 3, a laser-type component measuring device is installed on a sintering machine, and the component concentration of a raw material charged layer surface layer charged in a pallet measured using the component measuring device is used. There is disclosed a technique of estimating the component concentration of a sinter ore and adjusting the compounding amount of a sintering raw material using the guess.

Japanese Patent No. 1464203 Japanese Patent No. 5544784 JP-A-60-262926

  The techniques disclosed in Patent Literature 1 and Patent Literature 2 measure the FeO concentration of the sinter and adjust the amount of the coagulant, the amount of granulated water, the amount of exhaust air, and the amount of city gas blown so as to be the target values. It is. However, it takes time for the results of these adjustments to be reflected in the components of the sinter, and if the reaction temperature for sintering rises, the cooler stops abnormally or the equipment downstream of the cooler fails. There is a possibility of causing equipment trouble such as.

  The technology disclosed in Patent Document 3 estimates the component concentration of the sintered ore from the component concentration of the raw material charging layer surface layer. It fluctuates due to segregation that accompanies the particle size of the binding material. For this reason, the relationship between the component concentration of the charging layer surface layer and the component concentration of the sintered ore is not uniform, and it is difficult to actually estimate the component concentration of the sintered ore from the component concentration of the charging layer surface layer. .

  The present invention has been made in view of such a problem of the related art, and an object of the present invention is to detect the fluctuation of the reaction temperature of sintering and detect the fluctuation of the reaction temperature even if the reaction temperature of sintering changes. An object of the present invention is to provide a method for producing a sintered ore capable of suppressing the occurrence of sinter.

The features of the present invention for solving such a problem are as follows.
(1) A method for producing a sintered ore in which water is added to a sintering raw material in which an iron-containing raw material, a CaO-containing raw material and a coagulant are blended, granulated, and sintered by a sintering machine to produce a sintered ore. A measuring step of continuously measuring the component concentration of the sinter, and adjusting the speed of the pallet truck to adjust the traveling speed of the pallet truck using the component concentration of the sinter measured in the measuring step. Process and
A method for producing a sintered ore, comprising:
(2) The method for producing a sintered ore according to (1), wherein the sintering raw material further contains at least one of an MgO-containing raw material and a SiO ₂ -containing raw material.
(3) The method for producing a sintered ore according to (1) or (2), wherein in the measuring step, the concentration of at least one or more components of FeO and C in the sintered ore is continuously measured. The production of the sintered ore according to any one of (1) to (3), further including a blending amount adjusting step of adjusting the blending amount of the coagulant of the sintering raw material using the component concentration of the ore. Method.
(5) In the sintering machine, at least one of gaseous fuel and oxygen is blown to sinter the sintering raw material, and at least one of the gaseous fuel and the oxygen is blown using the component concentration of the sinter. The method for producing a sintered ore according to any one of (1) to (4), further comprising a step of adjusting a blowing amount for adjusting the amount.

  By carrying out the method for producing a sintered ore of the present invention, the component concentration of the sintered ore is continuously measured, and the traveling speed of the pallet truck of the sintering machine is changed. Thereby, the temperature rise of the sintered ore on the outlet side of the cooler can be suppressed, and equipment troubles such as equipment failure of the sintering machine can be suppressed.

FIG. 1 is a schematic diagram illustrating an example of a sinter ore manufacturing apparatus 10 that can perform the method of manufacturing a sinter according to the present embodiment. FIG. 2 is a graph showing the time change of the FeO concentration of the sinter, the traveling speed of the pallet truck, the mixing ratio of the coke breeze, and the temperature of the sinter at the outlet of the cooler in the example. FIG. 3 is a graph showing the time change of the FeO concentration of the sinter, the traveling speed of the pallet truck, the mixing ratio of the coke breeze, and the temperature of the sinter at the outlet of the cooler in the comparative example.

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

The raw material supply unit 20 includes a plurality of compounding tanks 22, 24, 25, 26, 28. The iron-containing raw material 12 is stored in the mixing tank 22. A CaO-containing raw material 16 containing limestone, quicklime, and the like is stored in the mixing tank 24. In the mixing tank 25, an MgO-containing raw material 17 containing dolomite, refined nickel slag, and the like is stored. The coagulant 18 containing coke breeze or anthracite crushed to a particle size of 1 mm or less using a rod mill is stored in the mixing tank 26. In the mixing tank 28, returned ore 74 (sinter ore sieved powder) having a particle size of 5 mm or less that has been sieved from the sinter is stored. A predetermined amount of each raw material is cut out from the mixing tanks 22, 24, 25, 26, and 28 of the raw material supply unit 20, mixed and formed into a sintering raw material on the conveyor 30. The sintering raw material is transported to the drum mixer 36 by the transport conveyor 30. A raw material containing SiO ₂ may be blended with the raw material for sintering. In this case, the SiO ₂ -containing raw material may be mixed with the iron-containing raw material 12 stored in the yard 11 in a predetermined amount, and a mixing tank for storing the SiO ₂ -containing raw material is separately provided. May be done.

The sintering raw material conveyed to the drum mixer 36 is charged into the drum mixer 36, and an appropriate amount of water 34 is added to the sintering material, for example, to be granulated into pseudo particles having an average particle diameter of 3.0 to 6.0 mm. The granulated sintering raw material is conveyed by a conveyor 38 to a sintering raw material supply device 42 of a sintering machine 40. The drum mixer 36 is an example of a granulator for granulating the sintering raw material, and a plurality of drum mixers 36 may be used, 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, or a high-speed stirrer may be installed upstream of the drum mixer 36 to stir the sintering raw material before the drum mixer 36 is charged. In the present embodiment, the average particle size is an arithmetic average particle size, Σ (Vi × di) (where, Vi is an 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 by the following formula: In the sintering machine 40, the sintering raw material granulated by the drum mixer 36 is sintered. 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 endlessly movable pallet truck 44 circulating and moving, an ignition furnace 46, and a wind box 48. The sintering raw material granulated from the sintering raw material supply device 42 is charged into the pallet of the pallet truck 44, and a charged layer of the sintering raw material is formed. The charged bed is ignited by the ignition furnace 46, and the air in the charged bed is sucked downward through the wind box 48, thereby moving the combustion and melting zones in the charged bed below the charged bed. Thereby, the charging layer is sintered to form a sintered cake. When the air in the bed is sucked downward through the wind box 48, at least one of gaseous fuel and oxygen may be blown from above the bed. The gaseous fuel is any combustible gas selected from blast furnace gas, coke oven gas, converter gas, city gas, natural gas, methane gas, ethane gas, propane gas, shale gas, and a mixture thereof.

  The sinter cake is crushed by the crusher 50 to be sinter. 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 apparatus 70 having a plurality of sieves, and sieved into a product sintered ore 72 having a particle size of more than 5 mm and a returned ore 74 having a particle size of 5 mm or less. Is done.

  The product sintered ore 72 is transported to the blast furnace 82 by the transport conveyor 76. An infrared spectrometer 80 is provided on a conveyor 76 for conveying the sintered product ore 72. In the infrared spectrometer 80, a measurement process is performed. In the measuring step, the concentration of at least one or more components of FeO and C in the product sintered ore 72 is continuously measured using the infrared spectrometer 80.

  The infrared spectrometer 80 irradiates the product sintered ore 72 with infrared light having a wavelength in the range of 0.5 to 50.0 μm, and receives reflected light from the product sintered ore 72. Since the molecular vibration of FeO contained in the product sintered ore 72 absorbs a specific wavelength component of the irradiated infrared ray, FeO gives the reflected infrared ray a specific wavelength component. The crystal structure of a monoatomic molecule such as C also starts to vibrate due to the irradiation of infrared rays, and imparts a unique wavelength component to the reflected infrared rays. Therefore, the component concentrations of FeO and C in the sintered product ore 72 can be measured by analyzing the irradiation infrared rays and the reflected infrared rays.

  The infrared spectrometer 80 irradiates infrared rays having a wavelength of 20 or more at a frequency of, for example, 128 times per minute, and receives the reflected light reflected on the product sinter 72. Since infrared rays can be emitted and received in such a short time, the infrared spectrometer 80 can continuously measure the component concentration of the product sinter 72 conveyed by the conveyor 76 online. The infrared spectrometer 80 is an example of an analyzer that measures the component concentration of the sintering raw material. Instead of the infrared spectrometer 80, a laser spectrometer that irradiates a laser to a measurement target, a neutron analysis that irradiates a neutron to a measurement target, A meter or a microwave analyzer that irradiates a measurement target with microwaves may be used.

  The sintered product ore 72 having a particle size of more than 5 mm is transported to the blast furnace 82 by the transport conveyor 76 and charged into the blast furnace as blast furnace raw material. On the other hand, the returned ore 74 having a particle size of 5 mm or less is transported by the transport conveyor 78 to the mixing tank 28 of the raw material supply unit 20.

  Since the product sintered ore 72 is obtained by cooling and sieving the sintered ore crushed by the crusher 50, the product sintered ore 72 and the sintered ore crushed by the crusher 50 and the ore return 74 Are sintered ores having the same component concentration. For this reason, the infrared spectrometer 80 may be provided between the cooler 60 and the sieving device 70, or may be provided on the transport conveyor 78. When the infrared spectrometer 80 is provided between the cooler 60 and the sieving device 70, the component concentration of the sintered ore after cooling is measured in the measuring step. When the infrared analyzer 80 is provided on the conveyor 78, the component concentration of the returned ore 74 is measured in the measuring step.

  In the present embodiment, the particle size of the product sintered ore 72 and the particle size of the ore return 74 mean a particle size sieved by a sieve. For example, a particle size of more than 5 mm means that a sieve having a mesh size of 5 mm is used. The particle size to be sieved on the sieve, and the particle size of 5 mm or less is the particle size to be sieved under the sieve using a sieve having an opening of 5 mm. Each value of the particle diameter of the product sintered ore 72 and the returned ore 74 is merely an example, and is not limited to this value.

  The method for producing a sintered ore according to the present embodiment includes a pallet truck speed adjusting step of adjusting the traveling speed of the pallet truck. In the step of adjusting the speed of the pallet truck, for example, the traveling speed of the pallet truck is adjusted using the FeO concentration of the product sintered ore 72 measured in the measuring process.

  The high FeO concentration of the product sinter 72 indicates that a large amount of magnetite remains in the product sinter 72, which indicates that the sintering reaction temperature is high and the sinter cake is heated to a high temperature. It is expected to be. For this reason, even if the sintered cake is pulverized and cooled by the cooler 60, the sintered ore cannot be cooled below the upper limit temperature on the outlet side of the cooler 60. There is a possibility that equipment trouble such as a failure of equipment downstream of 60 will be caused.

  For this reason, the correspondence between the FeO concentration of the sinter and the sinter temperature at the outlet of the cooler 60 is grasped in advance for each traveling speed of the pallet truck, and the FeO concentration exceeding the upper limit temperature at the outlet of the cooler 60 is determined. A management value is determined in advance. In the adjustment process of the pallet truck, when the FeO concentration of the product sintered ore 72 is higher than the control value, and the sinter ore temperature at the outlet side of the cooler 60 calculated from the above correspondence is predicted to exceed the upper limit temperature. Then, the traveling speed of the pallet truck is adjusted to reduce the traveling speed of the pallet truck. If the traveling speed of the pallet truck is reduced, the cooling time of the chiller 60 becomes longer, so that the temperature of the sintered ore on the exit side of the chiller 60 becomes lower. As described above, since the temperature of the sintered ore on the exit side of the cooler 60 can be lowered, occurrence of equipment troubles such as abnormal stop of the cooler 60 and failure of equipment on the downstream side of the cooler 60 can be suppressed.

  In the above example, the FeO concentration of the product sintered ore 72 is continuously measured in the measurement process, and the FeO concentration of the product sintered ore 72 rises above the control value. Although the example in which the traveling speed of the pallet truck is adjusted when the condensing temperature exceeds the upper limit temperature has been described, the C concentration of the product sintered ore 72 may be measured instead of the FeO concentration in the measurement process. The correspondence between the C concentration of the sinter and the sinter temperature at the outlet of the cooler 60 is grasped in advance, and a control value of the C concentration exceeding the upper limit temperature of the outlet of the cooler 60 is determined in advance. If the value rises above the control value, the traveling speed of the pallet truck is reduced. This indicates that the temperature in the width direction of the sintering machine was not uniform and C was not burned, thereby increasing the C concentration, indicating that unsintered ore was discharged. . For this reason, the traveling speed of the pallet truck is reduced to completely burn C on the sintering machine, and abnormal stoppage of the cooling machine 60 due to the combustion of C in the cooling machine 60 or in the equipment downstream of the cooling machine 60. The occurrence of equipment trouble due to the combustion of C at the time can be suppressed.

  The method for producing a sintered ore according to the present embodiment adjusts the blending amount of the coagulant as a sintering raw material using the concentration of at least one or more of FeO and C of the product sintered ore 72 measured in the measuring step. The method may further include a step of adjusting the blending amount. For example, even if the FeO concentration of the product sinter 72 is higher than the control value and the sintering reaction temperature is expected to be high, the compounding amount of the coagulant should be reduced by the compounding amount adjusting step. Thus, the sintering reaction temperature can be lowered. After lowering the sintering reaction temperature, the pallet truck speed can be returned in the process of adjusting the speed of the pallet truck, so the productivity of sinter decreases due to the slower pallet truck speed. Can be suppressed. If the change in the reaction temperature of sintering can be suppressed by adjusting the blending amount of the coagulant, the change in the FeO concentration of the sinter is suppressed, and the quality of the sinter increases.

  The method for producing a sintered ore according to the present embodiment uses the concentration of at least one or more components of FeO and C in the sintered ore measured in the measuring step to determine a blowing amount of at least one of gaseous fuel and oxygen. The method may include a step of adjusting the blowing amount to be adjusted. For example, even when the FeO concentration of the sinter is higher than the control value and the sintering reaction temperature is expected to be high, at least one of the gaseous fuel and oxygen is injected by the injection amount adjusting step. By reducing the amount, the time during which the sintering reaction temperature is maintained at a high temperature can be shortened. After shortening the high-temperature holding time of the sintering reaction temperature, the progress speed of the pallet truck slowed down in the process of adjusting the speed of the pallet truck can be returned. Can be suppressed. If the reaction temperature fluctuation of sintering can be suppressed by adjusting at least one of the injection amounts of the gaseous fuel and oxygen, the fluctuation of the FeO concentration of the sinter is suppressed, and the quality of the sinter increases.

  In the present embodiment, each raw material is cut out from the mixing tanks 22, 24, 25, 26, and 28 of the raw material supply unit 20 and mixed, and the raw material is converted into a sintering raw material by the transport conveyor 30 and granulated by the drum mixer 36. However, the present invention is not limited to this. For example, a sintering raw material including the iron-containing raw material 12, the CaO-containing raw material 16, the MgO-containing raw material 17, and the ore return 74 is put into the drum mixer 36, water is added to the sintering raw material, and granulation is performed. By charging the coagulant 18 in the latter half, the carbon material exterior particles having the coagulant 18 in the surface layer may be used as the granulated sintering raw material.

  The sintering raw material obtained by mixing the iron-containing raw material 12, the CaO-containing raw material 16, the MgO-containing raw material 17, and the ore return 74, and a part of the coagulant 18 is charged into the drum mixer 36, and water is added to the sintering raw material. In the latter half of the granulation, the remaining part of the coagulant 18 is added, and the carbon material exterior particles in which the coagulant 18 is present on the surface layer of the granulated sintering raw material are converted into the granulated sintering raw material. May be used. Coke powder or anthracite is used as a coagulant added in the latter half of granulation by adding water to the coagulation raw material.

  In the case where a plurality of drum mixers 36 are provided, and in the case of using carbon-coated particles in which the coagulant 18 is present in the surface layer, a part or all of the coagulant 18 is put into the latter half of the last drum mixer 36. Alternatively, the sintering raw material may be charged into the drum mixer 36 by the above-described method to granulate the carbon material exterior particles having the coagulant 18 in the surface layer. Furthermore, when a plurality of drum mixers 36 are used, all of the water to be added to the sintering raw material may be added to the first drum mixer 36, and some of the water may be added to the first drum mixer 36. And the rest may be added by another drum mixer 36.

  In the present embodiment, each raw material is cut out from the mixing tanks 22, 24, 25, 26, and 28 of the raw material supply unit 20 and mixed, and the raw material is converted into a sintering raw material by the transport conveyor 30 and granulated by the drum mixer 36. However, the present invention is not limited to this. For example, a sintering raw material containing the iron-containing raw material 12, the MgO-containing raw material 17 and the ore return 74 is put into the drum mixer 36, water is added to the sintering raw material, and granulation is performed. The granulated particles in which the CaO-containing raw material 16 and the coagulant 18 are present in the surface layer by adding the coagulant 16 and the coagulant 18 may be used as the granulated sintering raw material.

  A sintering raw material obtained by mixing a part of the iron-containing raw material 12, the MgO-containing raw material 17 and the ore return 74, and the coagulant 18 is put into a drum mixer 36, and water is added to the sintering raw material to granulate the raw material. By charging the remainder of the iron-containing raw material 12 and the CaO-containing raw material 16 in the latter half of the granulation, the granulated particles having the iron-containing raw material 12 and the CaO-containing raw material 16 in the surface layer are granulated and sintered. It may be used as a raw material.

  The sintering raw material obtained by mixing the iron-containing raw material 12, the ore return 74, the MgO-containing raw material 17, and a part of the CaO-containing raw material 16 is charged into a drum mixer 36, and the sintering raw material is granulated by adding water. By blending the remainder of the CaO-containing raw material 16 and the coagulant 18 in the latter half of the granulation, the granulated particles having the CaO-containing raw material 16 and the coagulant 18 present in the surface layer can be used as the granulated sintering raw material. Good.

  A sintering raw material obtained by blending the iron-containing raw material 12, the ore return 74, the MgO-containing raw material 17, a part of the CaO-containing raw material 16, and a part of the coagulant 18 is put into a drum mixer 36, and water is added to the sintering raw material. Is added, and granulation is carried out. By mixing the remainder of the CaO-containing raw material 16 and the balance of the coagulant 18 in the latter half of the granulation, the granulated particles having the CaO-containing raw material 16 and the coagulant 18 in the surface layer are obtained. It may be used as a granulated sintering raw material.

  In the case where a plurality of drum mixers 36 are used and granulated particles in which the CaO-containing raw material 16 or the CaO-containing raw material 16 and the coagulant 18 are present in the surface layer, a part or all of the CaO-containing raw material is used. The granulated particles having the CaO-containing raw material 16 and the coagulant 18 in the surface layer by introducing the coke 16 and the coagulant 18 into the latter half of the last drum mixer 36 and charging the sintering raw material into the drum mixer 36 by the method described above. May be granulated.

  In the present embodiment, an example has been shown in which the respective raw materials are cut out from the mixing tanks 22, 24, 25, 26, and 28 of the raw material supply unit 20 and mixed, and the raw materials are sintered on the conveyor 30. However, the present invention is not limited thereto. . For example, a part of each raw material cut out from the mixing tanks 22, 24, 25, 26, and 28 of the raw material supply unit 20 is transported directly to the drum mixer 36 by the transport conveyor 30, and the remaining part is transported by a transport conveyor different from the transport conveyor 30. After being conveyed to a high-speed stirring device and subjected to a stirring treatment, the mixture is granulated by a granulator such as a drum mixer 36 or a pelletizer and, if necessary, dried by a drier and then charged into the conveyor 30 or 38. Good. After the stirring process, the mixture may be directly charged into the conveyor 30 without granulation by a granulator such as a drum mixer 36 or a pelletizer. Further, at least one of a crushing step and a sieving step may be provided before the stirring treatment with the high-speed stirring device. When a plurality of drum mixers 36 are used, the drum mixers 36 may be fed to a conveyor between any of the drum mixers.

  Further, the number of infrared analyzers 80 in the measurement process is not limited to one, and a plurality of infrared analyzers 80 may be provided. A plurality of infrared analyzers 80 may be used to measure the concentration of at least one or more components of FeO and C in the sintered ore.

  In both Examples and Comparative Examples, sintered ore was manufactured using the sintered ore manufacturing apparatus 10 shown in FIG. In both Examples and Comparative Examples, an infrared analyzer 80 was installed on the conveyor 76, and the FeO concentration was continuously measured at a frequency of 18 times per hour as the component concentration of the sinter, and the measured FeO concentration was used. The sinter was manufactured for 5 hours by adjusting the mixing ratio of coke breeze as a coagulant so that the FeO concentration of the sinter became the FeO control value. In both Examples and Comparative Examples, the raw material pile containing dust having a high C concentration was changed after one hour.

  The embodiment is an example having a pallet truck speed adjusting step for adjusting the traveling speed of the sintering machine pallet truck, and the comparative example is an example having no pallet truck speed adjusting step. Therefore, when the FeO concentration of the sinter becomes high, in the embodiment, the traveling speed of the pallet truck is reduced and the mixing ratio of the coke breeze is adjusted to cope with it. In the comparative example, the traveling speed of the pallet truck is adjusted. And the mixing ratio of coke breeze was adjusted.

  FIG. 2 shows the FeO concentration (% by mass) of the sinter in the example, the traveling speed of the pallet truck (m / min), the mixing ratio of the coke breeze (% by mass), and the sinter temperature (° C.) at the outlet of the cooler. 4 is a graph showing a time change of FIG. FIG. 3 shows the FeO concentration (mass%) of the sinter in the comparative example, the traveling speed of the pallet truck (m / min), the mixing ratio of the coke breeze (mass%), and the sinter temperature (° C.) on the exit side of the cooler. 4 is a graph showing a time change of FIG.

  Since the measuring step for continuously measuring the FeO concentration of the sintered ore by the infrared spectrometer 80 is provided, it is possible to early detect that the FeO concentration of the sintered ore is higher than the FeO control value after the material pile is changed. Since it was detected that the reaction temperature of sintering increased due to the increase in the FeO concentration and the temperature of the sinter ore on the outlet side of the cooler exceeded the upper limit temperature, in the embodiment, the sintering machine was used in the step of adjusting the speed of the pallet truck. The traveling speed of the pallet truck was reduced and the mixing ratio of coke breeze was adjusted. As a result, an increase in the temperature of the sinter ore at the outlet of the cooler was suppressed, and the operation could be performed without exceeding the upper limit temperature of the outlet of the cooler. After the FeO concentration returned to the control value by adjusting the mixing ratio of the coke breeze, the traveling speed of the pallet truck was returned to the original speed. Thereby, the decrease in the productivity of the sinter could also be suppressed.

  As described above, in the method for manufacturing a sintered ore according to the present embodiment, when the FeO concentration of the sintered ore is continuously measured and the increase in the FeO concentration of the sintered ore is detected, the traveling speed of the pallet truck of the sintering machine is determined. To adjust. As a result, it was confirmed that the rise in the temperature of the sinter ore on the outlet side of the cooler can be suppressed, the load on the cooler and subsequent equipment can be reduced, and equipment troubles such as equipment failure can be avoided.

  In the comparative example as well, it was detected that the temperature of the sintered ore on the outlet side of the cooler exceeded the upper limit temperature from the increase in the FeO concentration of the sintered ore, so the mixing ratio of the coke breeze was adjusted. However, the temperature of the sinter at the outlet of the cooler decreases only after about 30 minutes have elapsed since the raw material already charged into the sintering machine was replaced after the mixing ratio of the coke breeze was adjusted. Before that, the temperature of the sinter increased above the upper limit temperature on the exit side of the cooler, and as a result, the cooler stopped abnormally. After the cooling machine and the pallet truck are stopped, the temperature of the sintering machine has dropped. Production has resumed.

  In both Examples and Comparative Examples, an increase in the FeO concentration of the sinter was detected, and when it was detected that the temperature of the sinter on the cooler exit side exceeded the upper limit temperature, the reaction temperature of sintering was increased. A sintering raw material derived from a raw material pile containing dust having a high C concentration is loaded on a pallet of a pallet truck of a sintering machine. In the comparative example, the mixing ratio of the coke breeze is adjusted, but the adjustment of the mixing ratio is reflected from the sintering raw material cut out from the raw material supply unit and mixed, and is already loaded on the pallet. It is not reflected in the sintering raw materials. For this reason, in the comparative example, the temperature of the sinter increased due to the increase in the reaction temperature of sintering, and the temperature of the sinter exceeded the upper limit temperature on the outlet side of the cooler. As a result, equipment troubles such as abnormal stop of the cooler occurred.

  In the embodiment, an increase in the FeO concentration of the sinter is detected, and when it is detected that the temperature of the sinter on the outlet side of the cooler exceeds the upper limit temperature, the traveling speed of the pallet truck is adjusted in the pallet truck speed adjusting process. Slow down. As a result, the cooling time of the sintering raw material already loaded on the pallet can be extended by the cooler, so that even if the reaction temperature of sintering of the sintering raw material increases, the sintering ore at the outlet side of the cooler can be reduced. Temperature rise can be suppressed, and thereby troubles such as abnormal stop of the cooler and equipment failure can be suppressed. In the present embodiment, an example is shown in which the measurement frequency of the infrared spectrometer 80 installed on the conveyor 76 is set to 18 times per hour. However, even if the measurement frequency is lower than this, the effect of adjusting the speed of the pallet truck can be obtained. The measurement frequency may be at least once every about 30 minutes required for the replacement of the raw materials charged in the sintering machine.

  As described above, in the method for manufacturing the sintered ore according to the present embodiment, the measurement of the FeO concentration of the sintered ore is continuously performed to detect an increase in the reaction temperature of sintering at an early stage, and to adjust the speed of the pallet truck. In the process, the traveling speed of the pallet truck is reduced. Thereby, for example, even when the reaction temperature of sintering is increased by changing to a raw material pile containing dust having a high C concentration, it is possible to suppress a rise in the temperature of the sintered ore on the exit side of the cooling machine, It has been confirmed that equipment troubles such as abnormal stoppage of sintering machine and equipment failure of sintering machine can be suppressed.

REFERENCE SIGNS LIST 10 sinter ore production apparatus 11 yard 12 iron-containing raw material 14 transport conveyor 16 CaO-containing raw material 17 MgO-containing raw material 18 coagulant 20 raw material supply unit 22 mixing tank 24 mixing tank 25 mixing tank 26 mixing tank 28 mixing tank 30 transfer conveyor 34 water 36 Drum mixer 38 Conveyor 40 Sintering machine 42 Sintering material supply device 44 Pallet truck 46 Ignition furnace 48 Wind box 50 Crusher 60 Cooler 70 Sieving device 72 Product sinter ore 74 Returning ore 76 Transport conveyor 78 Transport conveyor 80 Infrared analyzer 82 Blast furnace

Claims (5)

A method for producing a sintered ore, which comprises adding water to a sintering raw material in which an iron-containing raw material, a CaO-containing raw material and a coagulant are blended, granulating the mixture, and sintering with a sintering machine to produce a sinter. ,
A sintering process in which the granulated sintering raw material is charged into a pallet truck and sintered to form a sinter cake;
A crushing step of crushing the sintered cake to obtain a sintered ore,
A cooling step of cooling the sinter,
A sieving step of sieving the cooled ore into product sintered ore and returned ore,
A measuring step of continuously measuring the concentration of at least one component of the cooled ore, the product ore and the ore return ;
Wherein using the measured component concentration of the sintered ore was in the measuring step, the adjustment step of the pallet truck speed to adjust the rate of progression of the pallet truck,
A method for producing a sintered ore, comprising: The method for producing a sintered ore according to claim 1, wherein at least one of an MgO-containing raw material and a SiO ₂ -containing raw material is further blended with the sintering raw material.   The method for producing a sintered ore according to claim 1 or 2, wherein in the measuring step, the concentration of at least one or more components of FeO and C in the sintered ore is continuously measured.   The sintered ore according to any one of claims 1 to 3, further comprising a blending amount adjusting step of adjusting the blending amount of the coagulant as a sintering raw material using the component concentration of the sintered ore. Manufacturing method. In the sintering machine, sintering the raw material by blowing at least one of gaseous fuel and oxygen,
The method according to any one of claims 1 to 4, further comprising a blowing amount adjusting step of adjusting the blowing amount of at least one of the gaseous fuel and the oxygen using the component concentration of the sinter. The method for producing a sintered ore according to the above.

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