APPARATUS FOR MANUFACTURING COMPACTED IRONS AND CONTROL METHOD THEREOF

Abstract

To provide a manufacturing apparatus of an agglomerate which can improve productivity of an agglomerate such as a molding coke, and a control method of the same.SOLUTION: A manufacturing apparatus of an agglomerate includes a pair of rolls which is fixed and provided at a predetermined gap, raw material supply adjustment means for dividing an amount of a raw material supplied to a gap between the pair of rolls in a width direction, and adjusting the amount, one or more pressure measurement means which are provided on each of the raw material supply adjustment means divided in the width direction, and measure a pressure acting on the raw material to which the pair of rolls is charged, and control means that controls the raw material supply adjustment means and to which a measurement value is supplied from the pressure measurement means, wherein the control means controls the raw material supply adjustment means divided in the width direction on the basis of the measurement value of the pressure by the pressure measurement means, and thereby agglomerates the raw material while controlling the amount of the raw material supplied to the gap between the pair of rolls in the width direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an apparatus for manufacturing compacted irons and a control method thereof. [Background technology]

[0002] In recent years, in order to improve the reactivity of coke, a technology has been developed in which carbon-containing materials (coal, etc.) are mixed with a binder and molded into lumps, and the lumps are then carbonized to produce molded coke, which can be used as a raw material for blast furnaces.

[0003] Among the molded cokes, those made by mixing a certain amount of carbon-containing material (coal, etc.) with iron-containing material (iron ore, etc.) and molding them into lumps are called ferro-coke. A method has been proposed for manufacturing molded coke in which the molded product is generally made by molding the mixed raw materials with a molding roll, and then carbonizing the molded product in a vertical carbonization furnace.

[0004] Conventionally, in the molding of mixed raw materials, in order to ensure that the quality of compacted iron is within an appropriate range, a method has been proposed in which the roll gap of a molding machine that molds the mixed raw materials by roll compression is controlled to suppress fluctuations in pressure between the rolls, thereby adjusting the pressing force when the raw materials are fed into the rolls.

[0005] For example, Patent Document 1 discloses a roll agglomeration machine including a pair of molding rolls that are pressed by a hydraulic cylinder with a predetermined pressure, the roll gap maintained at this predetermined pressure can be continuously changed, and the rotation speed can be adjusted, and a powder supplying device. The powder supplying device in Patent Document 1 includes a screw feeder and a casing for the screw feeder that are installed above the pair of molding rolls. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2011-57970 A [Patent Document 2] JP 2014-172060 A Summary of the Invention [Problem to be solved by the invention]

[0007] In Patent Document 1, powder is supplied and pressed onto a pair of forming rolls by the rotation of a screw feeder, and the powder is agglomerated into plates as the rotating rolls rotate. The rotation speed of the screw feeder is controlled so that the gap between the pair of forming rolls is constant.

[0008] However, the technology proposed in Patent Document 1 requires a roll gap adjustment mechanism, such as a hydraulic servo or an electric one, to control the roll gap. This not only complicates the device configuration but also requires maintenance and management of the roll gap adjustment mechanism.

[0009] Therefore, it has been desired to ensure high quality of compacted irons produced by a manufacturing device with a simple structure, but when a manufacturing device with a simple structure is adopted, the controllability is poor with the conventional control method, and it is difficult to automatically control the pressure. Therefore, an operator needs to manually control the pressure between the rolls while constantly monitoring the molding pressure.

[0010] In response to this, Patent Document 2 proposes a control method that makes it possible to suppress the molding pressure fluctuation without controlling the roll gap and ensure the quality of the compacted irons within an appropriate range.

[0011] However, it has been found that the technology proposed in Patent Document 2 is not very effective in achieving uniform dispersion across the width of the forming roll. That is, due to raw material segregation in the raw material hopper above the screw feeder that feeds the raw material into the forming roll, the amount of raw material fed to the forming roll differs across the width, so the forming pressure at the forming roll becomes non-uniform across the width, which is a factor in reducing the forming yield.

[0012] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an apparatus for manufacturing compacted irons and a control method thereof that can improve the productivity of compacted irons such as molded coke. [Means for solving the problem]

[0013] In order to solve the above-mentioned problems and achieve the object, an apparatus for manufacturing compacted irons according to the present invention includes a pair of rolls fixedly disposed with a predetermined gap therebetween, raw material supply adjusting means for adjusting an amount of raw material supplied to the gap between the pair of rolls by dividing it in a width direction, at least one pressure measuring means provided for each of the raw material supply adjusting means divided in the width direction and measuring a pressure that the pair of rolls apply to raw material input thereto, and control means for controlling the raw material supply adjusting means and receiving a measurement value from the pressure measuring means, wherein the control means controls the raw material supply adjusting means divided in the width direction based on the pressure measurement value by the pressure measuring means, thereby agglomerating the raw material while controlling in the width direction the amount of raw material supplied to the gap between the pair of rolls.

[0014] Furthermore, in the apparatus for manufacturing compacted irons according to the present invention, the control device has control tables, each of which is the number of raw material supply adjustment means divided in the width direction, the control tables being configured from a predetermined target value of pressure to be applied to the raw material fed from the pair of rolls, a deviation between the target value of pressure and the measured value of pressure by the pressure measuring means, and a control variable of the raw material supply adjustment means, the control device calculates a deviation between the target value of pressure and the measured value of pressure by the pressure measuring means, retrieves a control variable of the raw material supply adjustment means in the control table from the target value of pressure and the deviation, and controls each raw material supply adjustment means based on the retrieved control variable.

[0015] In order to solve the above-mentioned problems and achieve the object, a method for controlling an apparatus for manufacturing compacted irons according to the present invention includes: a pair of rolls fixedly installed with a predetermined gap therebetween; raw material supply adjusting means for adjusting an amount of raw material supplied to a gap between the pair of rolls by dividing it in a width direction; pressure measuring means for measuring a pressure to be applied to raw material input by the pair of rolls by the number of the raw material supply adjusting means divided in the width direction; and control means for controlling the raw material supply adjusting means and receiving a measured value from the pressure measuring means, wherein the control means controls the raw material supply adjusting means divided in the width direction based on the pressure measured by the pressure measuring means, thereby agglomerating the raw materials while controlling in the width direction the amount of raw material supplied to the gap between the pair of rolls. Effect of the Invention

[0016] According to the apparatus for manufacturing compacted irons and a control method thereof according to the present invention, when manufacturing compacted irons by molding mixed raw materials using a pair of molding rolls, the mixed raw materials can be uniformly charged into the pair of molding rolls in the depth direction, thereby making it possible to manufacture compacted irons of high quality with high productivity. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram showing a configuration of a manufacturing apparatus for compacted irons according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a flowchart showing a flow of a control method of the apparatus for manufacturing compacted irons according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A manufacturing apparatus for compacted irons and a control method thereof according to an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiment described below.

[0019] (Production equipment for compacted irons) The configuration of an apparatus for manufacturing compacted irons according to an embodiment will be described with reference to Fig. 1. In the apparatus for manufacturing compacted irons, a pair of rolls are rotated in opposite directions to supply raw materials into a gap, whereby the raw materials are compression-molded into compacted irons (molded products). At this time, since a difference in the supply amount in the width direction affects the quality of the molded products, if the difference in the supply amount becomes large, the quality difference of the molded products increases, making quality control difficult. Therefore, in the present invention, a plurality of raw material supply adjusting means are provided to reduce this deviation.

[0020] As shown in FIG. 1, the apparatus 1 for manufacturing compacted irons includes a raw material hopper 2, a pair of screw feeders 4, a plurality of adjusting gates 5 and 6, a pair of molding rolls 7, load cells 8 and 9, and a controller 10.

[0021] The raw material hopper 2 has, for example, a funnel shape. The raw material hopper 2 drops raw materials for compacted bodies (briquettes), for example, granular powder raw materials (hereinafter referred to as "raw materials") 3 obtained by crushing coal and iron ore and mixing a binder, from a discharge port.

[0022] The screw feeder 4 functions as a raw material conveying means for conveying the raw material 3 to the adjustment gates 5 and 6. The screw feeder 4 is configured as a pair, and each includes a motor 4a, 4b controlled by the control device 10. Each screw feeder 4 conveys the raw material 3 put into the raw material hopper 2 to the adjustment gates 5 and 6 by rotating, for example, a spiral screw by the motor 4a, 4b. Note that the screw feeder 4 is configured as multiple shafts as shown in FIG. 1, and therefore also functions as a raw material supply adjusting means for adjusting the amount of raw material supplied to the forming roll 7 in the width direction.

[0023] The adjustment gates 5 and 6 function as raw material supply adjustment means for dividing and adjusting the amount of raw material 3 supplied to the gap (roll gap) between a pair of molding rolls 7 in the width direction. A plurality of adjustment gates 5 and 6 are arranged side by side in the width direction, for example, above the roll gap between the pair of molding rolls 7. In this embodiment, the "width direction" refers to the width direction of the molding rolls 7.

[0024] The adjustment gates 5, 6 are equipped with motors 5a, 6a controlled by the control device 10. The motors 5a, 6a move the adjustment gates 5, 6 up and down, for example, to adjust the gate opening of the adjustment gates 5, 6. The amount of raw material 3 supplied to the forming roll 7 is controlled by adjusting the gate opening of the adjustment gates 5, 6. In other words, when the gate opening of the adjustment gates 5, 6 is increased, the amount of raw material 3 introduced is increased, and when the gate opening of the adjustment gates 5, 6 is decreased, the amount of raw material 3 introduced is decreased.

[0025] The pair of molding rolls 7 are provided below the adjustment gates 5 and 6, and are fixed to the manufacturing apparatus 1 as a pair on the left and right with a predetermined roll gap between them. The molding rolls 7 are equipped with a motor 7a controlled by the control device 10. The raw material 3 that is dropped by gravity and extruded from the adjustment gates 5 and 6 is supplied to the roll gap of the molding rolls 7. In addition, the molding rolls 7 are provided with corresponding pockets (not shown) on the rotating surface.

[0026] The roll gap of the molding rolls 7 is changed depending on, for example, changes in the composition or mix of the raw materials 3, but is fixed at a predetermined roll gap during operation of the manufacturing apparatus 1. The molding rolls 7 rotate in opposite directions to each other so as to pressurize the raw materials 3 passing through the roll gap and push out the compacted irons formed by the pressure. In addition, the amount of raw materials 3 fed into the roll gap of the molding rolls 7 is adjusted by adjusting the gate opening of the adjustment gates 5 and 6 arranged above the molding rolls 7.

[0027] The load cells 8, 9 function as pressure measuring means for measuring the pressure applied to the input raw material 3 by the pair of forming rolls 7 for the number of adjustment gates 5, 6 divided in the width direction. The load cells 8, 9 also function as supply amount estimating means for estimating the supply amount of raw material 3 from the measured pressure. The load cells 8, 9 are installed near (outside) the forming rolls 7 and measure the inter-roll pressure of the pair of forming rolls 7. Furthermore, one or more load cells 8, 9 are provided for each of the adjustment gates 5, 6 divided in the width direction.

[0028] As the supply amount estimating means, a contact or non-contact level meter may be used instead of the load cells 8 and 9.

[0029] The control device 10 controls the gate opening of the adjustment gates 5 and 6, and functions as a control means to which measurement values ​​are supplied from the load cells 8 and 9. The control device 10 is composed of a processing unit such as a CPU (Central Processing Unit), a recording unit such as a ROM (Read Only Memory), a RAM (Random Access Memory) and a hard disk, and an input unit that can input data from the outside (all not shown). The control device 10 also includes control table storage units 10a and 10b.

[0030] The control device 10 controls the gate opening of the adjustment gates 5, 6 divided in the width direction based on the pressure measurements by the load cells 8, 9, thereby agglomerating the raw material 3 while controlling the amount of raw material 3 supplied to the roll gap between a pair of forming rolls 7 in the width direction.

[0031] In the control device 10, a pressure target value related to the pressure in the forming rolls 7 is set according to the composition and mix of the raw material 3. Data on this pressure target value is stored in the control table storage units 10a and 10b of the control device 10. Furthermore, in the control table storage units 10a and 10b, table data of, for example, "pressure target value x pressure actual deviation" is stored.

[0032] In addition, the control table 10a stores, for example, data of the pressure target value for the load cell 8 on the back side of the paper in Fig. 1, table data of "pressure target value x pressure actual deviation." In addition, the control table 10b stores, for example, data of the pressure target value for the load cell 9 on the front side of the paper in the same figure, table data of "pressure target value x pressure actual deviation."

[0033] The control device 10 is supplied with measured values ​​of pressure between the rolls of the forming rolls 7 from the load cells 8 and 9. The control device 10 controls the motors 5a and 6a based on the measured values ​​supplied from the load cells 8 and 9, thereby controlling the gate opening degrees of the adjustment gates 5 and 6.

[0034] The control device 10 has control tables each consisting of a target value of pressure to be applied from the forming roll 7 to the raw material 3, a deviation between the target value of pressure and the pressure measured by the load cells 8, 9, and a control amount for the adjustment gates 5, 6, for the number of adjustment gates 5, 6. The control device 10 calculates the deviation between the target value of pressure and the pressure measured by the load cells 8, 9, and retrieves the control amount for the adjustment gates 5, 6 in the control table from the target value of pressure and the deviation. Then, based on the retrieved control amount, the control device 10 controls the gate opening degree for each adjustment gate 5, 6 so that the pressure measured by the load cells 8, 9 becomes the target value.

[0035] In this manner, in the manufacturing apparatus 1, adjustment gates 5, 6 divided into multiple pieces in the width direction are provided above the roll gap of the forming roll 7, and load cells 8, 9 in the width direction, the same number as the number of adjustment gates 5, 6, are provided on the outside of one of the forming rolls 7.

[0036] As a result, when raw material 3 is supplied, the pressure according to the supply amount is measured by the load cells 8, 9. In addition, in the manufacturing device 1, a pressure target value is set in advance to achieve the target molding quality, and the adjustment gates 5, 6 corresponding to the same position in the width direction are raised and lowered so that the measurement values ​​of the load cells 8, 9 become the pressure target value. By raising these adjustment gates 5, 6, the supply amount of raw material 3 increases and the pressure increases, while by lowering the adjustment gates 5, 6, the opposite occurs, making it possible to control the supply amount of raw material 3 at each position.

[0037] (Method of Controlling Apparatus for Manufacturing Compacted Irons) A control method for the apparatus for manufacturing compacted irons according to the embodiment will be described with reference to Fig. 2. In the following, a control method will be described in which the raw material supply adjusting means is of the split gate type and the measurement method is the load cells 8 and 9.

[0038] First, the measured values ​​(pressure measured values) of the load cells 8 and 9 are supplied to the control device 10 (step S1). Then, the control device 10 processes the measured values ​​(step S2). Then, the control device 10 compares the processed measured values ​​with a pressure target value (step S3).

[0039] Next, the control device 10 judges whether the absolute value of the deviation between the pressure target value and the measured value is within a preset range (step S4). If it is judged in step S4 that the absolute value of the deviation is not within the set range (No in step S4), the control device 10 retrieves an output value (control amount) from the control table stored in the control table storage units 10a and 10b (step S5). Next, the control device 10 changes the opening degree of the adjustment gates 5 and 6 based on the retrieved output value (step S6).

[0040] Next, the control device 10 determines whether or not compacted irons are being manufactured (whether or not the manufacturing of compacted irons is to be continued) (step S7). If it is determined that compacted irons are not being manufactured (No in step S7), the control device 10 ends this process.

[0041] Here, when it is determined in step S4 that the absolute value of the deviation is within the set range (Yes in step S4), the control device 10 performs the processes in step S7 and after. When it is determined in step S7 that compacted irons are being manufactured (Yes in step S7), the control device 10 returns to step S1 and performs the processes in step S1 and after.

[0042] According to the above-described manufacturing apparatus for compacted irons and its control method, when manufacturing compacted irons by molding mixed raw materials using the pair of molding rolls 7, the mixed raw materials can be uniformly charged in the depth direction between the pair of molding rolls 7. This makes it possible to manufacture compacted irons of high quality with high productivity.

[0043] (Example) An example of the manufacturing apparatus for compacted irons and a control method thereof according to the embodiment will be described. In this example, an adjustment gate is used as the raw material supply adjustment means, and a load cell is used as the supply amount estimation means, and the standard deviation of molded product IDs for each number of adjustment gates is estimated.

[0044] Here, the number of adjustment gates and the number of load cells installed are the same. The quality of the compacted irons is evaluated by ID strength (30 / 15) (hereinafter referred to as "formed product ID"). The size of the compacted irons is 30 mm x 25 mm x 18 mm (6 cc) and their shape is egg-shaped. The estimated effect model assumes that when an infinite number of adjustment gates and load cells exist, the standard deviation of the molded product ID approaches 0 infinitely.

[0045] In this example, assuming that the adjustment gate is ideally controlled (= the pressure of the molding roll for each width unit, i.e., the amount of material flowing in per width unit, is equal), the standard deviation of the molding ID was calculated using the following formula (1).

[0046] y = a ln(x) + b (1) Where, x: number of adjustment gates, y: standard deviation of molded product ID, a, b: constants

[0047] Of these, constant b is the standard deviation of the molded product ID when there is one adjustment gate, and since this is 0.045 based on the measurement results using an actual machine, the constant is determined as follows:

[0048] a=-0.005,b=0.045

[0049] Using this model formula, the standard deviation of the molded product ID was estimated for each number of adjustment gates, and the results are shown in Table 1.

[0050] [Table 1]

[0051] As shown in Table 1, it was confirmed that the standard deviation of molded product IDs decreased as the number of adjustment gates increased. These results demonstrated the effectiveness of dividing the adjustment gates.

[0052] Although the apparatus for manufacturing compacted irons and a control method thereof according to the present invention have been specifically described above with reference to the preferred embodiments and examples, the gist of the present invention is not limited to these descriptions and should be broadly construed based on the claims. Furthermore, it goes without saying that various changes and modifications based on these descriptions are also included in the gist of the present invention. [Explanation of symbols]

[0053] 1. Compacted iron manufacturing equipment 2 Raw material hopper 3 Raw materials 4. Screw feeder 4a, 4b Motor 5,6 Adjustment gate 5a,6a Motor 7 Forming roll 7a Motor 8,9 Load cells 10 Control device 10a, 10b Control table storage unit

Claims

1. A pair of rolls fixedly provided with a predetermined gap therebetween; A raw material supply adjusting means for adjusting the amount of raw material supplied to the gap between the pair of rolls by dividing it in the width direction; a pressure measuring means for measuring a pressure applied to the raw material input by the pair of rolls, the pressure measuring means being provided for each of the raw material supply adjusting means divided in the width direction; a control means for controlling the raw material supply adjusting means and receiving a measurement value from the pressure measuring means; Equipped with the control device controls the raw material supply adjusting device divided in the width direction based on a value of the pressure measured by the pressure measuring device, thereby agglomerating the raw materials while controlling an amount of raw material supplied to the nip of the pair of rolls in the width direction.

2. 2. The apparatus for manufacturing compacted irons of claim 1, wherein the control device has control tables, each of which is the number of raw material supply adjusting means divided in the width direction, the control tables being configured from a predetermined target value of pressure to be applied to the raw material fed from the pair of rolls, a deviation between the target value of pressure and the pressure measured by the pressure measuring means, and a control variable of the raw material supply adjusting means, the control device calculates a deviation between the target value of pressure and the pressure measured by the pressure measuring means, searches for a control variable of the raw material supply adjusting means in the control table from the target value of pressure and the deviation, and controls each raw material supply adjusting means based on the searched-out control variable.

3. A control method for an apparatus for manufacturing compacted irons, comprising: a pair of rolls fixedly disposed with a predetermined gap therebetween; raw material supply adjusting means for adjusting an amount of raw material supplied to the gap between the pair of rolls by dividing it in a width direction; pressure measuring means for measuring a pressure applied to the raw material input by the pair of rolls by the number of the raw material supply adjusting means divided in the width direction; and control means for controlling the raw material supply adjusting means and receiving a measured value from the pressure measuring means, the control device controls the raw material supply adjusting device divided in the width direction based on a value of the pressure measured by the pressure measuring device, thereby agglomerating the raw materials while controlling an amount of raw material supplied to the nip of the pair of rolls in the width direction.

Images