JP5748890B2 - Metal manufacturing method - Google Patents

Description

  The present invention relates to a method for producing a metal, and more particularly to a method for producing a metal capable of stabilizing the additive concentration in an electrolytic solution during electrolytic purification and performing appropriate management of operation.

  One method for producing a metal is electrolytic purification. For example, when performing electrolytic purification of copper, an additive is generally added to the electrolytic solution. The additive is used for improving the deposited state of copper in the cathode plate. For example, organic additives such as glue, gelatin, and lignin (pulp waste liquor) that form protective colloids and organic substances that have functional groups such as thiourea and aloin are commonly used. The In general, the activation polarization at the time of deposition is increased by the additive, and the uniform electrodeposition is improved by increasing the polarization, so that the deposited metal can be dense and have a uniform surface. Since such additives are gradually consumed as electrolysis continues, it is necessary to add them from time to time. Until now, additives are usually put into the dissolution tank for daily use, dissolved at about 50 ° C while keeping warm, and added to the electrolyte during operation. It was done by driving.

  When electrolytic copper is produced by electrolytic purification, for example, thiourea exerts its effect by adhering to the surface of electrolytic copper, but the sulfur content (S content) contained in thiourea is a problem in the quality of electrolytic copper. Therefore, additive concentration control is an important production factor. Further, it is known that when the additive is dissolved, the additive is decomposed by raising the temperature of the additive solution, and the effect is reduced. For this reason, in order to increase the production efficiency of electrolytic copper, the operation was performed by adjusting the amount of the additive in advance so as to obtain an optimal additive concentration. In addition, glue and gelatin have protein as a main component, and are easily decomposed in an acidic / high-temperature electrolytic solution. Similarly, the amount of addition was adjusted in advance in consideration of the amount of decomposition.

  About the method of measuring the density | concentration of the additive in electrolyte solution, it describes in patent document 1, for example. Patent Document 1 discloses a method for measuring a glue concentration. An electrolytic solution is electrolyzed with a constant current in an electrolytic cell to obtain a cathode potential change rate of the electrolytic cell, and a calibration curve in which the cathode potential change rate is set in advance. In this way, the concentration of glue is measured so that the concentration of glue in the electrolyte can be measured quickly.

Japanese Patent Laid-Open No. 10-158881

  However, if the amount of additive added to the electrolytic solution is increased in consideration of the amount of decomposition in advance, the concentration of the additive in the electrolytic solution increases, and there is a problem that the power consumption during the production of electrolytic copper due to voltage increase is deteriorated. It was. Further, when the additive is thiourea, an increase in the amount added to the electrolytic solution causes an increase in the quality of S (sulfur) in the electrolytic copper, and the product cannot be produced. Therefore, in order to operate with the decomposition amount of the additive minimized, it is not a conventional batch operation, but the additive is continuously poured into the dissolution tank little by little, and the additive solution is electrolyzed. A method in which liquid is continuously fed into the liquid is preferable.

  In this way, the additive concentration in the electrolyte during operation greatly affects the quality of the metal produced, so it is necessary to appropriately control the concentration of the additive, but the temperature change of the electrolyte during operation When there is a short circuit between the cathode plate and the anode plate, decomposition and consumption of the additive are promoted and the additive concentration changes greatly. Accordingly, when the concentration of the additive in the electrolytic solution changes greatly, it is easily guessed that there is an abnormality such as a rise in the temperature of the electrolytic solution during operation or the occurrence of a short circuit between the cathode plate and the anode plate.

  Therefore, the present invention has been made in view of such problems, and is in operation by appropriately adjusting the concentration of the additive solution in the additive solution to be added to the replenishing electrolytic solution to be supplied to the operating electrolytic cell. In addition to stabilizing the additive concentration in the electrolyte solution, if there is a significant change in the additive concentration, it is judged that the operation is abnormal, thereby promptly finding the abnormal part and appropriately managing the operation. An object of the present invention is to provide a metal production method that can be performed.

In order to solve the above-mentioned problem, the invention according to claim 1 is a method for producing a metal by electrolytic refining, wherein the replenishing electrolytic solution to which the additive is added is continuously supplied into the electrolytic cell. Sampling the electrolyte solution in the vicinity of the mouth and the electrolyte solution in the drain tank extracted from the electrolyte tank at predetermined intervals to measure the concentration of the additive, and adding the electrolyte solution in the drain tank When the concentration of the agent is lower than the predetermined set value, the feeder device that supplies the additive to the dissolution tank for dissolving the additive is accelerated to increase the supply amount of the additive, and the electrolyte near the supply port If the concentration of the additive exceeds the predetermined set value, the feeder device operation is slowed down to reduce the supply amount of the additive, and the concentration of the additive in the electrolyte in the drainage tank and the vicinity of the supply port When the concentration of the additive in the electrolyte is within the set range It is by maintaining the supply of the additive from the feeder device, without concentration of the additive in the electrolytic solution recovered to the drainage tank from the electrolytic tank Waru falls below a predetermined concentration, and a supply port Suppress the decomposition of the additive by adjusting the concentration of the additive solution by continuously cutting out the required amount of the additive so that the concentration of the additive in the electrolyte in the vicinity is within the predetermined concentration range However, the present invention provides a method for producing a metal, characterized in that the amount of additive added to the electrolyte solution for replenishment before being supplied to the electrolytic cell is adjusted.

In order to solve the above-mentioned problem, the present invention according to claim 2 is the method for producing a metal according to claim 1, wherein the concentration of the additive in the electrolyte solution in the vicinity of the supply port and the drainage tank are recovered. Monitoring is performed so that the difference between the concentration of the additive in the electrolytic solution is within a predetermined range, and if the difference in the concentration of the additive deviates from the predetermined range, it is determined that the operation is abnormal. .

In order to solve the above problems, the present invention according to claim 3 is the method for producing a metal according to claim 1, wherein the additive is thiourea and the electrolyte is recovered from the electrolytic cell to the drainage cell. Before supplying to the electrolytic cell so that the concentration of thiourea in the electrolyte solution in the vicinity of the supply port is in the range of 2.5 to 5.0 ppm so that the concentration of thiourea in the electrolyte does not fall below 2.0 ppm The amount of thiourea added to the replenishing electrolyte solution is adjusted.

In order to solve the above problem, the present invention according to claim 4 is the method for producing a metal according to claim 2, wherein the additive is thiourea, and the concentration of thiourea in the electrolyte solution near the supply port the difference between the concentration of thiourea drainage electrolytic solution recovered to the tank monitor so that 0.5～3.0Ppm, operation in the case where the difference between the concentration of the additive was departing from its scope It is characterized that it is judged as abnormal.

  In order to solve the above problem, the present invention according to claim 5 is the method for producing a metal according to claim 3 or 4, wherein the concentration of thiourea in the electrolyte recovered from the electrolytic cell to the drainage cell is The amount of thiourea added to the replenishing electrolyte before being supplied to the electrolytic cell is adjusted so as to be close to 2.0 ppm.

According to the method for producing a metal according to the present invention, for supplementation in which an additive is added so that the concentration of the additive in the electrolytic solution recovered from the electrolytic bath to the drainage bath does not fall below a predetermined concentration. Add to the electrolyte for replenishment before supplying to the electrolytic cell so that the concentration of the additive in the electrolytic solution in the vicinity of the supply port that continuously supplies the electrolytic solution to the electrolytic cell is within the specified concentration range it and was therefore to adjust the amount of additive can be added only additive amount necessary in the electrolytic solution in the electrolytic refining, there is an effect that it is possible to stabilize the additive concentration.

Also, monitor the difference between the concentration of the additive in the electrolyte near the supply port and the concentration of the additive in the electrolyte recovered in the drain tank to be within a predetermined range. When the difference deviates from the specified range, it was determined that the operation was abnormal.Therefore, the prompt detection of abnormal points such as a rise in electrolyte temperature and the occurrence of a short between the cathode and anode plates was promoted. There is an effect that appropriate management can be performed.

It is a block diagram of one Embodiment of the apparatus for enforcing the manufacturing method of the metal which concerns on this invention. It is a front view which shows a feeder apparatus. It is a front view which shows the detail of the screw of a feeder apparatus. It is a front view which shows the detail of the hopper part of a feeder apparatus. It is explanatory drawing which shows the motion of a throwing chute. It is side surface sectional drawing which shows the structure of a hopper. It is a flowchart which shows one Embodiment of the manufacturing method of the metal which concerns on this invention. It is a flowchart which shows the step which judges abnormality of operation. It is a flowchart which shows the step which minimizes the addition amount of thiourea.

  First, after describing a metal production apparatus for carrying out the metal production method according to the present invention, a preferred embodiment of the metal production method according to the present invention will be described in detail. FIG. 1 is a block diagram of an embodiment of an apparatus for carrying out a metal manufacturing method according to the present invention.

[Configuration of metal manufacturing equipment]
Various metals are produced by electrolytic purification. In the present embodiment, a case where copper is produced by electrolytic purification will be described as an example. First, an electrolytic purification apparatus 1 which is a copper manufacturing apparatus shown in FIG. 1 is roughly an electrolytic tank 11 filled with an electrolytic solution 10 and a drainage tank for quantitatively recovering the electrolytic solution 10 from the electrolytic tank 11. 12, a supply tank 13 for quantitatively supplying a new electrolyte solution 10 for replenishment to the electrolytic tank 11, a hydrochloric acid tank 14 for storing hydrochloric acid 140 as one of the additives, and a supply tank 13 The electrolytic solution supply tank 15 for storing the electrolytic solution 10 is provided, and the additive dissolving device 2 and the additive solution supply device 3 are further provided. In addition, a pump 17a is provided in the middle of a pipe 16a for transferring the electrolytic solution 10 collected in the drain tank 12 to the supply tank 13, and a pipe for transferring the hydrochloric acid 140 stored in the hydrochloric acid tank 14 to the supply tank 13. A pump 17b is provided in the middle of 16b, and a pump 17c is provided in the middle of the pipe 16c for transferring the fresh electrolyte 10 stored in the electrolyte supply tank 15 to the supply tank 13. A pump 17d is disposed in the pipe 16d for transferring the electrolytic solution 10 to which the additive stored in the tank is added to the electrolytic cell 11.

  In the electrolytic cell 11, a plurality of anodes (not shown) formed by casting crude copper serving as an anode, and a plurality of cathode plates 5 for growing copper by electrodepositing copper on the electrodeposition surface. Are alternately immersed at a predetermined interval. In addition, the electrolytic solution 10 is supplied to the electrolytic cell 11 via a supply tank 13. The electrolytic solution 10 is supplied from a supply port (not shown) provided on the lower side of one end portion in the longitudinal direction of the electrolytic cell 11 and is collected from the upper side of the opposite end portion. As the cathode plate 5, a stainless steel plate is used for electrolysis purification by the permanent cathode method (PC method). The additive dissolving device 2 continuously dissolves the additive used in the electrolytic purification, and the additive solution 200 dissolved by the additive dissolving device 2 is put into the supply tank 13 by the additive solution supplying device 3. It is continuously supplied into the stored electrolyte 10.

[Configuration of additive dissolution apparatus]
The additive dissolution apparatus 2 includes a dissolution tank 23 for dissolving the additive and a first feeder device 22a that is an additive supply apparatus for continuously adding the additive to the dissolution tank 23. Dissolution apparatus 20a, a second dissolution apparatus 20b including a second feeder apparatus 22b which is an additive supply apparatus for continuously adding other additives to the dissolution tank 23, and a solvent in the dissolution tank 23. A solvent supply device 50 constituted by a valve 50a and a pipe 50b, a liquid level measuring device 27 for measuring a change in height of the liquid level of the additive solution 200 stored in the dissolution tank 23, The electronic thermometer 28 for measuring the temperature of the additive solution 200 in the dissolution tank 23 is provided. The operations of the first feeder device 22a, the second feeder device 22b, and the solvent supply device 50 are controlled by the control device 30, and the additive tank 200 adjusted in the dissolution tank 23 is supplied to the supply tank 13. A pump 25 is provided in a pipe 24 for transporting to the pipe. In FIG. 1, the pipes 16 a, 16 b, and 24 reach the supply tank 13 in a connected state. However, the pipes 16 a, 16 b, and 24 are not limited to this, and may separately reach the supply tank 13 independently. . In addition, the solvent in this embodiment is water.

  In the present embodiment, two types of additives, thiourea 60a and glue 60b, are used as additives, and these additives are dissolved and mixed in one dissolution tank 23. Therefore, the additive dissolution apparatus 2 is the first dissolution apparatus. Two systems, 20a and a second dissolving device 20b, are provided. As described above, the additive supply device 2 may be provided in a necessary number according to the type of additive to be added to the electrolytic solution 10 or a mixture of a plurality of additives in a predetermined ratio in advance. It can also be set as the structure which provides only one by using.

  The upper surface of the dissolution tank 23 is hermetically sealed by an upper surface plate 23b, and an axial fan 23c is attached to the upper surface plate 23b. By exhausting the air in the space in the dissolution tank 23 to the outside by the axial fan 23c, the steam generated inside the dissolution tank 23 is discharged to the outside, and the pressure inside the dissolution tank 23 is set to a charging chute 220a, which will be described later. The pressure is relatively lower than the pressure in the first feeder device 22a and the second feeder device 22b communicated through 220b. By forming in this way, it is prevented that the vapor | steam generate | occur | produced in the melting tank 23 reaches the 1st feeder apparatus 22a and the 2nd feeder apparatus 22b, and moisture is absorbed and solidified or deteriorated. In particular, since the thiourea 60a has high hygroscopicity, such a configuration makes it possible to prevent solidification and dissolve smoothly.

  In addition, a pipe 23a for passing steam is disposed around the dissolution tank 23, and the additive solution 200 stored in the dissolution tank 23 is kept at a predetermined temperature, for example, 50 ° C. by heat exchange. Be able to. In addition, it is good also as a structure which heat-reserves an additive solution by distribute | circulating warm water through the piping 23a, and it is also possible to cool the additive solution 200 by distribute | circulating cold water.

[Configuration of additive supply device]
The 1st feeder apparatus 22a and the 2nd feeder apparatus 22b which supply an additive to the dissolution tank 23 are comprised using "CE-W" type | mold "biaxial screw type cassette weighting feeder" by Kubota Corporation, for example. can do. Here, since the 1st feeder apparatus 22a and the 2nd feeder apparatus 22b are provided with the substantially same structure, the structure is demonstrated below based on the 1st feeder apparatus 22a. The first feeder device 22a is also referred to as a loss infeeder. As schematically shown in FIG. 2, the base 221; a drive unit 222 installed on the base 221; The screw mechanism 223 that is rotationally driven, the hopper portion 224 that is disposed above the screw mechanism 223 and supplies the additive to the screw mechanism 223, and the additive that has been fed to the end of the screw mechanism 223 is discharged. A discharge cylinder 235 and a load cell 26a for measuring the amount of the discharged additive are provided. The discharge tube 235 is connected to a charging chute 220 a that serves as an additive supply path to the dissolution tank 23.

  FIG. 3 is a diagram showing details of the screw of the screw mechanism 223. As shown in FIG. 3, the screw mechanism 223 includes screws 225a and 225b having spiral screw blades 226 provided on the outer periphery thereof, and these can be rotated by the driving unit 222 in a state where they are arranged in parallel. It is stored. The screw blades 226 of the screws 225a and 225b are installed with a slight gap so as not to contact each other. As a result, a necessary amount of additive is continuously cut out and supplied into the dissolution tank 23.

  FIG. 4 is an exploded view showing details of the hopper 224. As shown in FIG. 4, the hopper portion 224 is installed in the upper portion of the screw mechanism 223 and has a bowl-shaped supply hopper 227 having a supply port for supplying an additive to the screw mechanism 223 at the lower portion, and the supply hopper 227. The agitator 228 is disposed in a state where it is supported by the shafts 227a and 227b, and is agitated to prevent the additive from solidifying by being driven to rotate by the driving unit 222, and the upper surface of the supply hopper 227. Gasket 229, clamp 230 installed on the upper surface of gasket 229, weighing hopper 231 installed on the upper surface of clamp 230, gasket 232 installed on the upper surface of weighing hopper 231, and installed on the upper surface of gasket 232 It comprises a clamp 233 and a lid 234 installed on the upper surface of the clamp 233. There. The additive, particularly thiourea 60a, is highly hygroscopic and easily solidified, so that it is stirred by the agitator 228 so as not to clump.

  The charging chute 220a that guides the additive to the dissolution tank is formed with an inclined portion that is slanted from the middle, and from a pipe 50b of the solvent supply device 50 to a predetermined location on the discharge cylinder 235 side of the charging chute 220a. Branched pipes 50c are connected to form a solvent introduction part 50d. When the additive is introduced into the dissolution tank 23 via the introduction chute 220a, the dissolution tank 23 is dissolved while the additive is dissolved by supplying a part of water as a solvent to be supplied to the dissolution tank 23 from the solvent introduction part 50d. Can be thrown into. Thus, the additive is smoothly and reliably dissolved without the additive being attached to the inner wall of the charging chute 220a.

  Further, as shown in FIG. 5, the charging chute 220 a can be rotated in the horizontal direction, and by providing a spare dissolution tank 29 separately from the dissolution tank 23, the two dissolution tanks 23 and 29 can be provided. It can be changed and used as appropriate. By providing the two dissolution tanks 23 and 29, when performing the maintenance of the dissolution tank 23, residue cleaning, or the like, continuous operation is possible without stopping the operation by using the other dissolution tank 29. In the present embodiment, the number of dissolution tanks is two, but the number is not limited to this, and three or more tanks may be provided. Further, in this embodiment, the throwing chute 220a is manually rotated, but it may be configured to automatically rotate by electric means or the like.

  The load cell 26a measures the weight of 10 members from the supply hopper 227 to the lid 234 and the additive contained in the hopper unit 224. That is, if the total weight Wh of 10 members from the supply hopper 227 to the lid 234 is measured in advance and the total weight Wt associated with the storage of the additive is measured with respect to this weight Wh, (Wt−Wh = By calculating Wn), the weight Wn of the additive in the hopper 224 can be measured.

  Further, the first dissolving device 20a and the second dissolving device 20b store additives for replenishing the additive that has been cut out from the first feeder device 22a and the second feeder device 22b, respectively. Hoppers 21a and 21b are provided. As shown in FIG. 6, the hoppers 21 a and 21 b include a main body 211 a that stores the additive, a crusher 211 b that is provided inside the main body 211 a, a motor 211 d that drives the crusher 211 b, and a first additive. The screw conveyor 211c is provided to be transferred to the feeder device 22a. Since the additive thiourea 60a is highly hygroscopic and easily hardened, the agglomerated additive is pulverized by the crusher 211b before being transferred to the first feeder device 22a and then transferred by the screw conveyor 211c. It has become. The addition of the additive to the hoppers 21a and 21b is performed by opening the upper surface cover 211e provided at the upper portion and introducing the additive contained in a flexible container (not shown) from the opening.

[Configuration of additive solution supply apparatus]
The additive solution supply device 3 is a device that continuously supplies the additive solution 200 dissolved by the additive dissolving device 2 into the electrolytic solution 10 through the supply tank 13. The additive solution 200 is supplied from the dissolution tank 23. The pump 25 is transferred to the supply tank 13, and the control device 30 controls the pump 25. The control device 30 also controls the first feeder device 22 a and the second feeder device 22 b and the pump 17 b that transfers the hydrochloric acid 140 to the supply tank 13. The control device 30 includes at least a central processing unit and a storage device (both not shown), and various measurement data and measurement data sent to the control device 30 based on a program stored in the storage device in advance. Various controls are executed by processing in the central processing unit using.

  The supply of the electrolytic solution 10 from the supply tank 13 into the electrolytic cell 11 is performed by continuously supplying the electrolytic solution 10 stored in the supply tank 13 into the electrolytic cell 11 at a constant flow rate. The new electrolytic solution 10 stored in the electrolytic solution supply tank 15, the electrolytic solution 10 extracted from the electrolytic tank 10 at a constant flow rate and collected in the drainage tank 12, and dissolved in the dissolution tank 23. The additive solution 200 and the hydrochloric acid 140 stored in the hydrochloric acid tank 14 are mixed and stored as the electrolyte solution 10 for supply. Thus, the electrolytic solution 10 collected in the drainage tank 12 is circulated and used. Then, the control device 30 controls the pump 25 so as to transfer the additive solution 200 adjusted in the dissolution tank 23 into the supply tank 13 at a predetermined flow rate. In the present embodiment, the control device is configured so that the flow rate of the electrolytic solution 10 supplied from the supply tank 13 to the electrolytic cell 11 and the flow rate of the electrolytic solution 10 collected from the electrolytic cell 11 to the drainage tank 12 are substantially the same. 30 is controlled.

[Production Method of Metal According to the Present Invention]
Next, a preferred embodiment of the metal production method according to the present invention will be described together with the operation of the electrolytic purification apparatus 1 described above.
In the production of copper by electrolytic refining, an abnormal electrodeposition phenomenon occurs when the concentration of thiourea 60a in the electrolyte 10 of the drainage tank 12 recovered from the electrolytic tank 11 is less than 2.0 ppm based on the experience of operation so far. When the concentration of the thiourea 60a in the electrolytic solution 10 is increased, the concentration of sulfur (S) in the electrolytic copper is increased, which causes a problem as a product. However, the electrolytic solution 10 is transferred from the supply tank 13 to the electrolytic cell 11. It has been confirmed that the sulfur (S) concentration in the electrolytic copper is not a problem unless the concentration of thiourea 60a in the electrolytic solution 10 near the supply port to be supplied is higher than 5.0 ppm. In addition, since thiourea 60a is consumed and reduced during electrolytic purification, in order to prevent the concentration of thiourea 60a in the electrolytic solution 10 of the drainage tank 12 from falling below 2.0 ppm, electrolysis during operation is performed. The concentration of thiourea 60a in the liquid 10 needs to be at least 2.0 ppm. Therefore, the concentration of thiourea 60a in the electrolyte solution 10 of the additive is one index, and the concentration of the thiourea 60a in the electrolyte solution 10 of the drainage tank 12 is a predetermined set value, which is 2.0 ppm in this embodiment. The thiourea 60a in the electrolytic solution 10 in the vicinity of the supply port for supplying the electrolytic solution 10 from the supply tank 13 to the electrolytic cell 11 is taken into consideration so that the thiourea 60a is effectively consumed. If the additive solution 200 is supplied from the dissolution tank 23 to the supply tank 13 by the additive solution supply device 3 so that the concentration of the additive becomes 2.5 to 5.0 ppm, appropriate electrolytic copper can be obtained. it is conceivable that. In order to effectively exhibit the effect while suppressing the amount of thiourea 60a used, the concentration of thiourea 60a in the electrolytic solution 10 in the drainage tank 12 is adjusted to be as close to 2.0 ppm as possible. It is preferable.

  Therefore, the electrolytic solution 10 in the vicinity of the supply port for supplying the electrolytic solution 10 from the supply tank 13 into the electrolytic cell 11 and the electrolytic solution 10 in the drainage tank 12 extracted from the electrolytic cell 11 are sampled at predetermined intervals. Then, the concentration of thiourea 60a in the electrolytic solution 10 is measured, and the control device 30 controls the operation of the first feeder device 22a of the first dissolving device 20a based on the measurement data, thereby adding the additive solution. The concentration of thiourea 60a in 200 can be adjusted. Note that the concentration measurement of the thiourea 60a in the electrolytic solution 10 is automatically performed every predetermined time, and the measurement data can be input to the control device 30. Alternatively, the operator can measure the concentration every predetermined time. The measurement data may be measured and the measurement data may be input to the control device 30. Here, in the present embodiment, the “electrolyte solution near the supply port” is provided with a supply port on the lower side of one end in the longitudinal direction of the electrolytic cell 11. It is.

  That is, when the concentration of the thiourea 60a in the electrolytic solution 10 sampled from the drainage tank 12 is lower than the set value of 2.0 ppm, the control device 30 controls the screw mechanism 223 of the first feeder device 22a. By increasing the operation speed, the supply amount of thiourea 60a supplied to the dissolution tank 23 is increased so that the concentration of thiourea 60a in the electrolyte in the drainage tank 12 does not fall below 2.0 ppm. Further, when the concentration of thiourea 60a in the electrolytic solution 10 sampled near the supply port exceeds 5.0 ppm which is the upper limit of the set value, the control device 30 causes the screw mechanism 223 of the first feeder device 22a. To the dissolution tank 23 so that the concentration of thiourea 60a in the electrolyte 10 near the supply port is within the range of 2.5 to 5.0 ppm without exceeding the upper limit of 5.0 ppm. The supply amount of thiourea 60a to be supplied is reduced. When the concentration of thiourea 60a is within the range of the conditions, the control device 30 maintains the supply amount from the first feeder device 22a as it is. The supply amount of the thiourea 60 a to the dissolution tank 23 is measured by a load cell 26 a provided in the first feeder device 22 a, and the measurement data is sent to the control device 30. On the other hand, the necessary water for the amount of thiourea 60a to be added is controlled by controlling the opening and closing of the valve 50a of the solvent supply device 50 by the control device 30, and the amount of water supply is measured by a flow meter (not shown). The measurement data is sent to the control device 30. Therefore, the necessary amount of thiourea 60a can be calculated from the measurement data. On the other hand, when the change in the liquid level in the dissolution tank 23 is measured by the liquid level measuring device 27, and the liquid level of the additive solution 200 in the dissolution tank 23 is below a predetermined liquid level. In the case where the control device 30 operates the additive dissolving device 2 to create the additive solution 200, and the liquid level of the additive solution 200 in the dissolving tank 23 becomes equal to or higher than a predetermined liquid level. The control device 30 stops the operation of the additive dissolving device 2.

Next, the concentration adjustment of the additive described above will be described in detail together with the flow of the copper manufacturing method.
The electrolytic bath 11 of the electrolytic purification apparatus 1 is filled with an electrolytic solution 10, and a plurality of anodes (not shown) serving as anodes and cathode plates 5 are alternately arranged. The supply tank 13 stores the electrolyte 10 in a state where additives such as thiourea 60a, glue 60b, and hydrochloric acid 140 for improving the copper deposition state in the cathode plate 5 are added. The thiourea 60a and glue 60b are dissolved in the dissolution tank 23, and the additive solution 200 is transferred to the supply tank 13 by the pump 25. A predetermined number of cathode plates 5 are successively carried into the electrolytic cell 11 at a predetermined interval by a carry-in / carry-out system (not shown). Then, by applying a predetermined DC voltage between the anode and the cathode plate 5, copper is subjected to electrolytic purification, and electrolytic copper is electrodeposited on the surface of the cathode plate 5. When electrolytic copper is electrodeposited on the surface of the cathode plate 5 to a predetermined thickness, the cathode plate 5 is unloaded from the electrolytic cell 11 by the loading / unloading system and transferred to a predetermined location. Thereafter, a new cathode plate 5 is carried into the electrolytic cell 11 by the carry-in system, and the above-described electrolytic purification process is performed again.

FIG. 7 is a flowchart of an embodiment of the method for producing a metal according to the present invention. Each step shown in FIG. 7 is executed by a command from the control device 30. First, a predetermined amount of thiourea 60a as an additive is charged into the hopper portion 224 of the first feeder device 22a and a predetermined amount of glue 60b as another additive is charged into the hopper portion 224 of the second feeder device 22b. (Step S1). When the additive is stored in each weighing hopper 231, the weighing (including the weight of the weighing hopper 231) of the additives (thiourea 60 a and glue 60 b) in each weighing hopper 231 is performed by the load cells 26 a and 26 b. We (step S2), and the measured value _{S 0} is sent to the controller 30. In the following description, the first feeder device 22a for introducing the thiourea 60a will be described, but the operation thereof is substantially the same as that for the second feeder device 22b for introducing the glue 60b.

Next, the control device 30 operates the screw mechanism 223 provided in the hopper portion 224 of the first feeder device 22a to supply the additive thiourea 60a to the charging chute 220a at a predetermined flow rate (step S3). ). Then, the control unit 30 is adapted to measure the weight of thiourea 60a after supply, the weight of thiourea 60a supplied to the chute 220a by comparing the measured values S ₁ and the previous measured value S ₀ calculate. On the other hand, the control device 30 opens the valve 50a of the solvent supply device 50 and starts supplying water as a solvent into the dissolution tank 23 (step S4). At this time, a part of the water is introduced into the solvent introduction part 50d through the pipe 50c branched from the pipe 50b of the solvent supply device 50, and the thiourea 60a is dissolved in the charging chute 220a while being dissolved in water. Supply is performed (step S5). And the control apparatus 30 transfers the additive solution 200 created and adjusted in the dissolution tank 23 by operating the pump 25 to the supply tank 13 (step S6). On the other hand, separately from the additive solution 200 containing the thiourea 60a and the glue 60b, hydrochloric acid 140 as an additive is supplied from the hydrochloric acid tank 14 to the supply tank 13. The supply tank 13 stores the fresh electrolyte 10 supplied from the electrolyte supply tank 15 and the electrolyte 10 continuously collected from the electrolyte tank 11 to the drain tank 12. The collected electrolytic solution 10 is recycled. Thus, the electrolytic solution 10 in the supply tank 13 to which the predetermined amount of additive is added is continuously supplied into the electrolytic cell 11 through the pump 17d.

  The electrolytic solution 10 in the drainage tank 12 extracted from the electrolytic cell 11 and the electrolytic solution 10 in the vicinity of the supply port of the electrolytic solution 10 supplied from the supply tank 13 into the electrolytic cell 11 are sampled every predetermined time ( Steps S7 and 11), the concentration of thiourea 60a in the electrolyte is measured. Then, the measured concentration of thiourea 60a is compared with the set values (2.0 ppm, 5.0 ppm) (steps S8, S12), and based on the result, the control device 30 determines the first dissolving device 20a. By controlling the operation of the first feeder device 22a, the amount of thiourea 60a supplied to the additive tank 23 is appropriately adjusted. Specifically, when the concentration of thiourea 60a in the electrolytic solution 10 sampled from the drainage tank 12 is lower than the set value of 2.0 ppm, the control device 30 controls the first feeder device 22a. When the speed of the screw mechanism 223 is increased to increase the supply amount of the thiourea 60a to the dissolution tank 23 (step S9), and the concentration of the thiourea 60a does not fall below the set value of 2.0 ppm, the control device 30 Maintains the supply amount of the thiourea 60a to the dissolution tank 23 without changing the speed of the screw mechanism 223 of the first feeder device 22a (step S10). On the other hand, the control device 30 compares the concentration of thiourea 60a in the electrolytic solution 10 sampled near the supply port (step S11) with the set value (2.5 to 5.0 ppm) (step S12), and the measured value. When the value exceeds 5.0 ppm which is the upper limit of the set value, the speed of the screw mechanism 223 of the first feeder device 22a is decreased to reduce the supply amount of the thiourea 60a to the dissolution tank 23 (step S13), When the concentration of thiourea 60a is in the range of 2.5 to 5.0 ppm which is a set value, the rotational speed of the screw mechanism 223 of the first feeder device 22a is maintained as it is, and the thiourea 60a is supplied and dissolved. (Step S10). In addition, since the thiourea 60a is decomposed by impurities in the anode and a change in the chlorine concentration of the electrolytic solution 10 even under normal operation, the concentration of the thiourea 60a in the electrolytic solution 10 sampled from the drainage tank 12 is reduced. If it is not less than 2.0 ppm, it has been found empirically that the concentration of thiourea 60a in the electrolyte 10 sampled in the vicinity of the supply port is less than 2.5 ppm. What is necessary is just to monitor whether the density | concentration of the urea 60a exceeds 5.0 ppm (step S12). On the other hand, in the flowchart of FIG. 7, the concentration of thiourea 60a in the electrolytic solution 10 in the drainage tank 12 is less than 2.0 ppm, and the concentration of thiourea 60a in the electrolytic solution 10 near the supply port exceeds 5.0 ppm. If this occurs, it is determined that the operation is abnormal as described later (see FIG. 8).

  In addition, as described above, when the concentration of thiourea 60a in the electrolyte 10 of the drainage tank 12 recovered from the electrolytic tank 11 is less than 2.0 ppm from the experience of operation so far, an abnormal electrodeposition phenomenon occurs. Although it has been confirmed, this means that the electrodeposition abnormality phenomenon does not occur unless the concentration of thiourea 60a in the electrolyte 10 of the drainage tank 12 collected from the electrolyte tank 11 is less than 2.0 ppm. Therefore, the amount of thiourea 60a used can be reduced to a minimum by maintaining the concentration of thiourea 60a in the electrolyte 10 of the drainage tank 12 collected from the electrolytic tank 11 as close to 2.0 ppm as possible. it can. Therefore, as shown in FIG. 9, after the steps S1 to S7 in FIG. 7, the concentration of the thiourea 60a in the electrolyte 10 of the drainage tank 12 is measured (step S8), and as a result, the thiourea is measured. When the concentration of 60a is higher than 2.0 ppm, the supply amount of thiourea 60a supplied to the dissolution tank 23 is reduced (step S31), and when the concentration becomes 2.0 ppm, the supply amount of thiourea 60a is decreased. By maintaining (step S32), the amount of thiourea 60a used can be reduced to a minimum.

  The supply amount of the thiourea 60a to the dissolution tank 23 is measured by a load cell 26a provided in the first feeder device 22a, and the measurement data is sent to the control device 30. On the other hand, the necessary water is supplied to the amount of thiourea 60a to be added by the control device 30 controlling the opening and closing of the valve 50a of the solvent supply device 50. Specifically, it is measured by a flow meter (not shown) provided in the solvent supply device 50. The concentration control of the additive can also be performed by adjusting the amount of solvent supplied.

  As described above, the control device 30 rotates the screws 225a and 225b of the screw mechanism 223 while appropriately controlling the rotation speed of the drive unit 222 of the first feeder device 22a, and the thiourea 60a discharge cylinder from the hopper unit 224. 235 is supplied to the dissolution tank 23 through the charging chute 220a. At this time, since the thiourea 60a is stirred by the agitator 228 in the supply hopper 227, solidification in the supply hopper 227 is prevented. Further, a part of water as a solvent supplied to the dissolution tank 23 is sent to the solvent introduction part 50d provided above the charging chute 220a via the pipe 50c, and the inside of the dissolution tank 23 is dissolved while dissolving the thiourea 60a. It is thrown into. Thus, by dissolving thiourea 60a with water quickly, dissolution is prevented from being inhibited by solidification due to moisture absorption. Further, the temperature of the additive solution is maintained at about 50 ° C. by circulating the steam through the pipe 23 a of the dissolution tank 23. Moreover, the additive cut out and reduced from the first feeder device 22a and the second feeder device 22b is sequentially replenished from the separately stored hoppers 21a and 21b. And since the hoppers 21a and 21b are equipped with the crusher 211b, even the additive which has high hygroscopicity and is easy to harden like the thiourea 60a can be smoothly supplied by appropriately crushing.

On the other hand, the operation is normally performed by monitoring the difference d between the concentration of thiourea 60a in the electrolytic solution 10 near the supply port and the concentration of thiourea 60a in the electrolytic solution 10 collected in the drainage tank 12. A determination is made whether or not. That is, as shown in FIG. 8, the measured value (step S21) of the concentration of thiourea 60a in the electrolytic solution 10 sampled from the drainage tank 12 (step S7) and the electrolysis sampled near the supply port (step S11). A difference d from the measured value of the concentration of thiourea 60a in the liquid 10 (step S22) is obtained (step S23). The inventors have empirically found that the thiourea 60a as an additive greatly changes when there is an abnormality such as a rise in the temperature of the electrolyte or the occurrence of a short circuit between the cathode plate 5 and the anode. If the difference d is in the range of 0.5 to 3.0 ppm, it is determined that the operation is normally performed (step S24). If the difference d is out of the range of 0.5 to 3.0 ppm, the operation is performed. It is determined that the process is not performed normally and is abnormal (step S23). Accordingly, it is possible to promptly find an abnormal part such as a rise in temperature of the electrolytic solution 10 or occurrence of a short circuit between the cathode plate 5 and the anode, thereby appropriately managing the operation. Here, the case where the concentration difference d of the thiourea 60a exceeds 3.0 ppm means that the thiourea 60a sharply decreases when the decomposition amount of the thiourea 60a increases due to the temperature rise of the electrolyte or when the current efficiency increases. When the concentration difference d is less than 0.5 ppm, the consumption of thiourea 60a is reduced due to a decrease in the amount of electrodeposition due to a decrease in current efficiency during electrolytic purification, This is considered to occur when the temperature is lower than normal and temperature degradation of the thiourea 60a is suppressed.

  As described above, the preferred embodiment of the present invention has been described in detail. However, the present invention is not limited to the specific embodiment, and within the scope of the gist of the present invention described in the claims, Needless to say, various modifications and changes are possible.

DESCRIPTION OF SYMBOLS 1 Electrolytic refining apparatus 2 Additive dissolution apparatus 3 Additive solution supply apparatus 5 Cathode plate 10 Electrolytic solution 11 Electrolytic tank 12 Drainage tank 13 Supply tank 14 Hydrochloric acid tank 15 Electrolytic solution supply tank 20a First dissolution apparatus 20b Second dissolution Device 22a First feeder device 22b Second feeder device 23 Dissolution tank 24 Pipe 25 Pump 26a, 26b Load cell 27 Liquid level meter 28 Electronic thermometer 30 Control device 1 Solvent supply device

Claims (5)

A method of producing a metal by electrolytic purification,
The electrolyte solution in the vicinity of the supply port for continuously supplying the electrolyte solution for replenishment with the additive added to the electrolytic cell, and the electrolyte solution in the drainage tank drawn out from the electrolytic cell, respectively, every predetermined time Sampling to measure the additive concentration,
When the concentration of the additive in the electrolytic solution in the drainage tank is lower than a predetermined set value, the operation of the feeder device that supplies the additive to the dissolution tank for dissolving the additive is accelerated. Increase the supply amount of the additive, if the concentration of the additive in the electrolyte near the supply port exceeds a predetermined set value, the operation of the feeder device is slowed to reduce the supply amount of the additive, Supply of the additive from the feeder device when the concentration of the additive in the electrolyte in the drainage tank and the concentration of the additive in the electrolyte near the supply port are within a predetermined set value range By maintaining the quantity as it is,
The concentration of the additive in the electrolytic solution recovered from the electrolytic bath to the drainage bath does not fall below a predetermined concentration, and the concentration of the additive in the electrolytic solution near the supply port is a predetermined concentration. The replenishment before supplying to the electrolytic cell while suppressing decomposition of the additive by adjusting the concentration of the additive solution by continuously cutting out the necessary amount of additive so as to be in the range of A method for producing a metal, comprising adjusting an amount of an additive added to an electrolytic solution. In the manufacturing method of the metal of Claim 1,
The concentration of the additive in the electrolyte near the supply port and the concentration of the additive in the electrolyte recovered in the drain tank are monitored so that the difference is within a predetermined range. A metal manufacturing method characterized by determining that the operation is abnormal when the difference between the values deviates from the predetermined range. In the manufacturing method of the metal of Claim 1,
The additive is thiourea;
The concentration of thiourea in the electrolyte solution in the vicinity of the supply port is 2.5-5 so that the concentration of thiourea in the electrolyte solution recovered from the electrolytic cell to the drainage cell does not fall below 2.0 ppm. A method for producing a metal, characterized in that the amount of thiourea added to the replenishing electrolytic solution before being supplied to the electrolytic cell is adjusted to be within a range of 0.0 ppm. In the manufacturing method of the metal of Claim 2,
The additive is thiourea;
Monitor the difference between the concentration of thiourea in the electrolyte near the supply port and the concentration of thiourea in the electrolyte recovered in the drain tank to be 0.5 to 3.0 ppm, and add method for producing a metal, characterized in that to determine the abnormality of the operation if the difference between the concentration of the agent falls outside its scope. In the manufacturing method of the metal of Claim 3 or 4,
The amount of thiourea added to the electrolyte for replenishment before being supplied to the electrolytic cell so that the concentration of thiourea in the electrolytic solution recovered from the electrolytic cell to the drained tank is close to 2.0 ppm. A method for producing a metal, characterized by adjusting.

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