The present invention relates to a control device of a granulator (briquetting machine) for producing granulated substances (briquettes) by successively supplying materials between a pair of rotating rolls and applying a high-compressive force to the supplied materials.
The briquetting machine produces the briquettes by successively supplying the materials between the pair of rotating rolls and applying the high-compressive force to the supplied materials (see Patent Documents 1 and 2, for example).
Conventionally, the briquetting machine for adjusting the briquette quality has been controlled by an operator to appropriately maintain the state of the briquetting machine, for example, the pressing load of the rolls, the power of the rolls, and the like. In this situation, as to the quality control in the production process of the briquettes by the briquetting machine, the operator regularly samples a part of the produced briquettes. The states of the sampled briquettes (briquette samples) can be determined as numeric values in consideration of the physical properties such as apparent density, crush strength, or the like. It is noted that the apparent density can be calculated by volume and weight of the briquette.
Patent Document 1: JP 2001-62280 A
Patent Document 2: JP H07-308565 A
The control of the conventional briquetting machine is, however, done by the operator's decision to maintain the state of the machine in an appropriate manner. Hence, such a control method is an indirect one in adjusting the briquette quality. For this reason, the quality control depends on the operator's decision. Even if the pressing load of the rolls and the power of the rolls are appropriately adjusted, there is a problem that the briquette quality is not in a desirable state, in some cases.
Therefore, the present invention has been made in view of the above problem, and has an object to provide a briquetting machine control device capable of improving the quality of the briquettes.
In order to solve the above problem, according to an aspect of the present invention, there is provided a briquetting machine control device for use in a briquetting machine having an operation set value adjusting unit and producing a briquette by successively supplying a material between a pair of rotating rolls and applying a high-compressive force onto the supplied material, the briquetting machine control device comprising: a briquette inspection device for sampling the briquette produced by the briquetting machine to measure a quality of the sampled briquette; and a controller for controlling the operation set value adjusting unit of the briquetting machine so that an actual measurement value about the quality of the briquette measured by the briquette inspection device comes closer to a predefined briquette quality target value, wherein a feeder adjusting unit for adjusting a rotation speed of a screw feeder, a pressing force adjusting unit for adjusting a pressing force of the pair of rotating rolls, and a roll adjusting unit for adjusting rotation speeds of the pair of rotating rolls each operate as the operation set value adjusting unit.
Preferably, the above-described briquetting machine control device further comprise a material characteristic measuring device for sampling the material to be supplied to the briquetting machine to measure a characteristic of the sampled material, wherein the controller comprises a briquette quality target value correcting unit for correcting the predefined briquette quality target value based upon the characteristic of the sampled material measured by the material characteristic measuring device, and wherein the controller controls each of the operation set value adjusting units of the briquetting machine so that the actual measurement value of the briquette measured by the briquette inspection device comes closer to the corrected briquette quality target value that has been corrected by the briquette quality target value correcting unit.
In addition, preferably, in the above-described briquetting machine control device, the controller sets each of operation set values of each of the operation set value adjusting units based upon the characteristic of the sampled material measured by the material characteristic measuring device, and then starts controlling each of the operation set value adjusting units of the briquetting machine, compares the actual measurement value about the quality of the briquette measured by the briquette inspection device with the briquette quality target value, with respect to each of the operation set values that have been set, and corrects each of the operation set values so that the actual measurement value about the quality of the briquette comes closer to the briquette quality target value, and controls each of the operation set value adjusting units of the briquetting machine based upon each of the operation set values that has been corrected.
According to the present invention, each of the operation set value adjusting units for adjusting the rotation speed of the screw feeder, the rotation speed of the rolls, the pressing force of the rolls, and the like of the briquetting machine is automatically controlled, based upon control information with sufficient objectivity such as the actual measurement values (measurement data) about the characteristics of the materials obtained by sampling the materials, or the actual measurement values (measurement data) about the quality of the briquettes obtained by sampling the briquettes that are products. Hence, it is possible to achieve more preferable operation situations than the settings of the operation states depending on the operator's decisions in a conventional briquetting machine. This improves the quality of the briquettes.
Hereinafter, a briquette production facility provided with a briquetting machine control device according to an embodiment of the present invention will be described with reference to the drawings as necessary.
The briquette production facility is provided with a briquetting machine 10 having a material supply inlet 1 at the upper part thereof as illustrated in
The feed hopper 2 has a funnel shape with its diameter enlarged upwardly, and has therein a screw feeder 3 having a spiral blade. In addition, a feeder driver 4 for driving the screw feeder 3 for rotation is provided at the upper part of the feed hopper 2 as a feeder adjusting unit for adjusting the rotation speed of the screw feeder 3.
An opening is arranged at the lower part of the feed hopper 2, and a pair of rolls 5 are arranged on both of left and right sides of the opening to be opposite to each other with respect to the opening. The pair of rolls 5 has a roll driver 6 as a roll adjusting unit for synchronously driving the rolls 5 at the same time and adjusting their rotation speeds. Further, one of the pair of rolls 5 has a hydraulic device 7 and a roll receded amount measuring sensor 8. The roll receded amount measuring sensor 8 is a measuring instrument capable of measuring the distance (receded amount) between the opposite rolls 5. Moreover, the hydraulic device 7 is a pressing force adjusting unit for adjusting the pressing force of the rolls 5. It is to be noted that each of the feeder driver 4, the roll driver 6, and the hydraulic device 7 corresponds to “an operation set value adjusting unit” described in “Solution to the Problem”.
Multiple depressed portions, not illustrated, are formed on each surface of the pair of rolls 5 making pairs, respectively, between the pair of rolls 5. Such paired depressed portions form a shape corresponding to a briquette B to be granulated in cooperation of the pair of rolls 5 with each other. When the rolls 5 are driven for rotation, materials M discharged from the lower part of the feed hopper 2 are pressed between the paired depressed portions. Thus, the briquette B having a desired shape is formed. Then, the shaped briquette B is discharged onto a transportation conveyor 23 from the lower parts of the pair of rolls 5, and is then carried out to the subsequent process by the transportation conveyor 23.
In this situation, the briquette production facility includes: a controller 31 for controlling the briquetting machine; a material characteristic measuring device 32 for measuring the quality of the materials; and a briquette inspection device 33 for measuring the quality of the briquette, as a control device of the briquetting machine 10, as illustrated in
In detail, the material characteristic measuring device 32 is provided in the vicinity of a material conveyor 22, and is capable of sampling the materials supplied to the briquetting machine 10 and measuring the characteristics thereof. The material characteristic measuring device 32 is configured to be capable of measuring grain size, bulk density, contained moisture amount, internal friction angle, and compressibility factor, as characteristics of the materials. The actual measurement values (measurement data) about material characteristic measured by the material characteristic measuring device 32 are output to the controller 31.
Additionally, the briquette inspection device 33 is arranged in the vicinity of the transportation conveyor 23 to sample the briquettes granulated by the briquetting machine 10, and is capable of measuring at least apparent density and crush strength as qualities of the sampled briquettes. The briquette inspection device 33 according to the present embodiment is capable of measuring the weight, volume, apparent density, and crush strength, as the qualities of the sampled briquettes, and at the same time, are capable of determining the yield rate of the briquettes. The actual measurement values (measurement data) about the qualities of the briquettes measured by the briquette inspection device 33 are also output to the controller 31.
The controller 31 is a controller including a personal computer. To the controller 31, the measurement data about the characteristics of the materials measured by the material characteristic measuring device 32, the measurement data about the qualities of the sampled briquettes measured by the briquette inspection device 33, and the measurement data about the receded amount output from the roll receded amount measuring sensor 8 are respectively input. Moreover, outputs of a feeder drive motor from the feeder driver 4 (hereinafter, also referred to as “feeder kW (kilowatt)”) and outputs of a roll drive motor from the roll driver 6 (hereinafter, also referred to as “roll kW (kilowatt)”) are also input to the controller 31, as the measurement data. Then, the controller 31 performs a program of a predefined briquetting machine control process to control the feeder driver 4, the roll driver 6, and the hydraulic device 7 based upon the predefined briquetting machine control process.
In the present embodiment, when the controller 31 performs the program of the briquetting machine control process, referring to
At step S30, the processing returns to step S10 with current operation set values being maintained. Herein, the “operation set values” are set values respectively corresponding to the rotation speed of the feeder driver 4, the rotation speed of the roll driver 6, and the pressing force of the hydraulic device 7. At step S40, it is determined whether or not the measurement data (actual measurement value) of the briquette obtained at step S10 is smaller than the given lower threshold with respect to the predefined briquette quality target value. That is to say, if the measurement data is under the allowable range of the predefined briquette quality target value (Yes), the processing proceeds to step S50. If not (No), the processing proceeds to step S60.
At step S50, the current operation set value is changed to a modified operation set value to improve the briquette quality by a predefined value, and the processing returns to step S10. At step
S60, since it is determined that the measurement data exceeds the allowable range of the predefined briquette quality target value, the current operation set value is changed to the modified operation set value to drop the briquette quality by a predefined value, and the processing returns to step S10. In this briquetting machine control process, the feeder driver 4, the roll driver 6, and the hydraulic device 7 constituting the operation set value adjusting unit of the briquetting machine 10 are controlled so that the measurement data (actual measurement value) of the briquette comes closer to the predefined briquette quality target value.
The setting of the above “briquette quality target value” will now be described with reference to
As to the “briquette quality target value”, a correlation line (i.e., a graph indicating a relationship between the apparent density and the crush strength) illustrated in
On the other hand, the rotation speed of the screw feeder 3, the pressing force of the pair of rolls 5, and the rotation speed of the pair of rolls 5, with respect to the briquette quality (i.e., the apparent density), can be defined and managed based upon the correlation with the apparent density of the briquette.
Specifically, referring to
Then, referring to
Herein, when the measurement data (actual measurement value) of the briquette is made to come closer to the predefined briquette quality target value, the specific feedback control of the “operation set value adjusting unit” is performed as follows. For example, in a case where the measurement data (actual measurement value) lies on a quality correlation line A and the apparent density and the crush strength of the briquette are both lower than the predefined range of the briquette quality target value as indicated by *(1) mark in
For example, in a case where the measurement data (actual measurement value) lies on the quality correlation line A and the apparent density of the briquette is higher than the predefined range of the briquette quality target value and the crush strength of the briquette is lower than the predefined range of the briquette quality target value as indicated by *(2) mark in
Which operation set value adjusting unit should be made to correspond to a change in which measurement data (actual measurement value) may naturally change depending on the different material, and depending on the type, the size, and the like of the briquettes to be produced. Therefore, the above quality correlation line, the operation set value, and its setting order are appropriately determined based upon the data of test results or the like that have been performed beforehand in accordance with the conditions on that occasion.
For example, the quality correlation line A is set to be the baseline in
In other words, in such a case, the baseline serving as the basis of settings deviates from the quality correlation line A.
Accordingly, if the quality correlation line A′ is stored as data beforehand, the controller 31 starts the corresponding control with the quality correlation line A′ changed to a new baseline.
Unless the quality correlation line A′ is stored as the data beforehand, the material characteristic measuring device 32 measures the characteristics of the materials, and in addition, the briquette inspection device 33 measures the quality of the briquettes produced with the materials and the new quality correlation line A′ is obtained from the quality results to be stored as a new baseline. Then, when the baseline corresponding to the characteristics of the materials is determined to be the new quality correlation line A′, the target range of the apparent density is set in accordance therewith. The roll pressing force and the roll rotation speed are determined to be conditions of starting the operation, based on the set target range. Thus, the operation of the briquetting machine starts, and then, it is controlled as described above so that the apparent density becomes constant (a target value), that is the pressing force of the pair of rolls becomes constant. For example, since the roll pressing force is proportional to the output from the roll drive motor (roll kW), the rotation speed of the feeder is controlled so that the output from the roll drive motor is constant. Modifications of the case where the quality correlation line changes will be described later.
Next, control and operation effects of the briquetting machine in the above-described briquette production facility will be described.
When the above-described briquette production facility is operated, the controller 31 starts operating the feeder driver 4, the roll driver 6, and the hydraulic device 7 with the predefined operation set values of the briquetting machine 10 being as the initial operation set values, based upon the initial operation set values. When the operation starts, the materials are successively supplied between the pair of rolls 5 that are rotating, and the briquette B is produced by the pair of rolls 5 applying a high-compressive force onto the supplied material M.
When the briquette is produced, the briquette inspection device 33 samples the briquette granulated by the briquetting machine 10 and measures the apparent density and the crush strength of the sampled briquette. The controller 31 controls each operation set value adjusting unit of the briquetting machine 10, while controlling each operation set value adjusting unit of the briquetting machine 10 so that the actual measurement value of the measured briquette comes closer to the predefined briquette quality target value in the processes of steps S10 to S60 of the above briquette control process, successively supplies the materials between the pair of rotating rolls, and applies the high-compressive force onto the supplied materials, for production of the briquettes.
That is, according to the briquette production facility, the briquette inspection device 33 and the controller 31 are included as a control device of the briquetting machine 10. The controller 31 automatically controls the feeder driver 4, the roll driver 6, and the hydraulic device 7 of the briquetting machine 10 so that the measurement data of the actual measurement values of the briquettes measured by the briquette inspection device 33 come closer to the predefined briquette quality target values. It is thus possible to provide more suitable operation situations than the settings of the operation states depending on the operator's decision in the conventional briquetting machine. Accordingly, it is possible to improve the quality of the briquettes.
It is to be noted that the briquetting machine control device according to the present invention is not limited to the above embodiment. Various modifications may occur without departing from the scope of the present invention.
For example, in the above embodiment, an example has been described such that as to the measurement data of the characteristics of the materials measured by the material characteristic measuring device 32, the materials to be supplied to the briquetting machine are sampled beforehand, the characteristics of the materials are measured beforehand, and the quality correlation line is obtained as a baseline for the initial settings from the quality results of the briquettes produced from the materials measured by the briquette inspection device 33. No description has been given as the control target of the controller 31 in the control device. However, the controller 31 can be further provided with a configuration of correcting the predefined briquette quality target value (briquette quality target value correcting unit) depending upon the measurement data of the characteristics of the materials measured by the material characteristic measuring device 32. Then, the controller 31 can be configured to control the feeder driver 4, the roll driver 6, and the hydraulic device 7 of the briquetting machine 10 so that the measurement data of the actual measurement values of the briquettes measured by the briquette inspection device 33 come closer to the briquette quality target value corrected by the briquette quality target value correcting unit.
To be specific, as indicated by a first modification in
When the briquettes are produced in the briquette production facility according to the first modification, the materials to be supplied to the briquetting machine 10 are sampled and the characteristics thereof are measured by the material characteristic measuring device 32 (step S1). The briquette quality target value is corrected based upon the characteristics of the measured materials (step S2). After that, the briquettes are produced in the same manner with the above embodiment.
That is, according to the first modification, it is possible to produce the briquettes by successively supplying the materials between the pair of rolls and applying the high-compressive force onto the supplied materials, while each operation set value adjusting unit of the briquetting machine 10 is being controlled so that the actual measurement values of the briquettes measured by sampling by the briquette inspection device 33 come closer to the briquette quality target value corrected by the briquette quality target value correcting unit. Accordingly, for example, in the case where there are the quality correlation line A and the quality correlation line A′ as illustrated in
Furthermore, as indicated by a second modification in
When the briquettes are produced in the briquette production facility according to the second modification, the materials to be supplied to the briquetting machine 10 are sampled and the characteristics thereof are measured by the material characteristic measuring device 32 (step S3). Each operation set value is determined based upon the characteristics of the measured materials (step S4). After that, the briquettes are produced in the same manner with the above embodiment.
That is, when the briquettes are produced in the briquette production facility according to the second modification, the controller 31 sets each operation set value of the feeder driver 4, the roll driver 6, and the hydraulic device 7, based upon the characteristics of the materials measured by the material characteristic measuring device 32. After that, the controller 31 starts the control of each operation set value adjusting unit of the briquetting machine 10. Then, the briquettes are produced by successively supplying the materials between the pair of rotating rolls and applying the high-compressive force onto the supplied materials, while sampling the briquettes produced with the operation set value that has been set based upon the characteristics of the materials, comparing the actual measurement value of the briquette measured by the briquette inspection device 33 with the briquette quality target value, correcting each operation set value so that the measurement data of the actual measurement value of the briquette comes closer to the briquette quality target value, and controlling each operation set value adjusting unit of the briquetting machine 10 based upon each operation set value that has been corrected. Accordingly, according to the second modification, for example, in the case where there are the quality correlation line A and the quality correlation line A′ as illustrated in
Furthermore, although not illustrated, the controller 31 can be configured to perform the program of the briquetting machine control process including the steps S1, S2, S3 and S4 described in the first and second modifications and all the processes at steps S10 to S60 in the above embodiment. With such a configuration, the briquette quality target value is corrected based upon the measurement data of the characteristics of the materials, and in addition, the operation starts after each operation set value is set based upon the actually measured characteristics of the materials. Therefore, this is more preferable for improving the quality of the briquettes.
Number | Date | Country | Kind |
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2012-258588 | Nov 2012 | JP | national |