JP2007224385A - Process for recovery of metal and equipment therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process and equipment for recovering heavy metals etc. as metals as valuable substances from a liquid to be treated containing them, by which only the metals to be recovered can be recovered as the metals as valuable substances from the liquid to be treated and in which a probability of containing impurities other than the metals to be recovered is low and, further, the recovery rate is high and also the purity of the metals recovered is high. <P>SOLUTION: The liquid to be treated in which the metals to be recovered are contained in the form of ions is allowed to flow into a reactor body. Metal wires composed of a metal having an ionization tendency higher than that of the metals to be recovered are put in the reactor body. The metals contained in the liquid to be treated are deposited by the difference of ionization tendency on the surfaces of the metal wires. Then, in the state where an ultrasonic oscillating body is brought into contact with the metal wires, the metal wires are vibrated by the ultrasonic oscillating body to strip off the deposited metals from the metal wires and recover them. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for recovering a metal, and more specifically, a waste liquid containing heavy metals such as Ni (nickel), Cu (copper), Sn (tin), In (indium), and Ga (gallium). The present invention relates to a method and an apparatus for recovering from a liquid as a valuable metal simple substance or alloy.

  In general, industrial waste liquids may contain various metals, and attempts have been made to collect them as valuable metals as simple substances. For example, plating factory waste liquid contains Ni, Cu, Zn, etc., semiconductor manufacturing factory waste liquid contains Cu, Ga, etc., and liquid crystal manufacturing factory waste liquid contains In etc. If these can be recovered, it becomes possible to reuse those metals.

  Conventionally, coagulation-precipitation treatment, co-precipitation treatment using chemicals, etc. are generally adopted as waste liquid treatment technology for recovering heavy metals, and when the concentration is low, metals can be removed using an adsorbent. It is done. As for metal recovery from the waste plating solution, there is a method in which iron scrap is put into the waste plating solution and a recovery target metal such as Cu is recovered by a cementation method. For example, there is an invention according to the following Patent Document 1 as a technique using coprecipitation processing.

JP 2002-126758 A

  However, in the coagulation sedimentation treatment using a chemical, there is a problem that a precipitate of hydroxide is generated as sludge. In addition, in the method in which iron scrap is introduced into the waste plating solution and Cu is deposited by the cementation method, the precipitation reaction ends when the deposited Cu covers the surface of the iron scrap, and the iron coated with Cu is recovered. As a result, only the target metal cannot be recovered as the metal to be recovered. In addition, there is a problem that only those having a low recovery rate and low purity can be obtained.

  The present invention has been made to solve such a problem, and can recover only a metal to be recovered from a liquid to be treated such as a waste liquid as a valuable metal simple substance or alloy, and recovery. It is an object of the present invention to provide a recovery method and apparatus that are less likely to contain impurities other than the target metal, have a high recovery rate, and a high purity of the recovery target metal.

  SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and the invention according to claim 1 relating to a metal recovery method is characterized in that a liquid to be processed containing a metal to be recovered in an ionic state is used as a reactor body. The metal wire 2 made of a metal that flows into the reactor and has a higher ionization tendency than the metal to be recovered is accommodated in the reactor body, and the metal contained in the liquid to be treated is converted into the metal wire by the difference in ionization tendency. 2, and then the metal wire 2 is vibrated by the ultrasonic oscillator 15 in a state where the ultrasonic oscillator 15 is in contact with the metal wire 2, and the deposited metal from the metal wire 2. It is characterized by recovering, characterized in that it is peeled off and recovered.

  The invention described in claim 2 is characterized in that, in the metal recovery method according to claim 1, the recovered metal deposit 3 is constituted by a large number of metal wires 2. Further, the invention according to claim 3 is the metal recovery method according to claim 2, wherein the recovered metal deposit 3 comprises a plurality of wire meshes 4 formed by intersecting a number of metal wires 2 vertically and horizontally. Has been. Further, the invention according to claim 4 is the metal recovery method according to claim 2 or 3, wherein the recovered metal deposit 3 is fixed in the reactor body. Furthermore, the invention according to claim 5 is the metal recovery method according to any one of claims 2 to 4, wherein the surface of the metal wire 2 constituting the recovered metal deposit 3 that contacts the ultrasonic oscillator 15 is arranged. The metal wire 2 to be formed is made of a metal having a smaller ionization tendency than the metal to be recovered.

  Furthermore, the invention according to claim 6 relating to the metal recovery apparatus is a metal wire made of a metal having a greater ionization tendency than the metal to be recovered while flowing the liquid to be processed containing the metal to be recovered in an ionic state. 2 is deposited on the metal wire 2 and the reactor main body 1 for performing a metal deposition reaction for depositing the metal contained in the liquid to be treated on the surface of the metal wire 2 due to the difference in ionization tendency. In order to recover the metal, an ultrasonic oscillator 15 for contacting the metal wire 2 and peeling the deposited metal from the metal wire 2 is provided.

  Furthermore, a seventh aspect of the invention is characterized in that, in the metal recovery apparatus according to the sixth aspect, the recovered metal deposit 3 is constituted by a large number of metal wires 2. Further, the invention according to claim 8 is the metal recovery apparatus according to claim 7, wherein the recovered metal deposit 3 comprises a plurality of wire meshes 4 formed by intersecting a number of metal wires 2 vertically and horizontally. It is characterized by being. Furthermore, a ninth aspect of the invention is characterized in that, in the metal recovery method according to the seventh or eighth aspect, the recovered metal deposit 3 is fixed in the reactor body 1. Furthermore, the invention according to claim 10 is the metal recovery method according to any one of claims 7 to 9, wherein the surface of the metal wire 2 constituting the recovered metal deposit 3 that contacts the ultrasonic oscillator 15 is arranged. The metal wire 2 to be formed is made of a metal having a smaller ionization tendency than the metal to be recovered.

  As described above, the present invention allows a liquid to be treated such as a waste liquid containing a metal to be recovered to flow into the reactor main body, accommodates a metal wire in the reactor main body, and causes a difference in ionization tendency in the waste liquid. The metal contained in the metal wire is deposited on the surface of the metal wire, and then the metal wire is vibrated by the ultrasonic wave oscillating body in a state where the metal wire is in contact with the ultrasonic wave oscillating body. Since the deposited metal is peeled off and collected, using such a metal wire increases the total surface area of the metal for the reaction compared to the conventional method using iron scrap, and the deposition reaction rate is increased. It is possible to improve the metal recovery efficiency because the reaction rate can be maintained by constantly exposing a new metal surface by peeling the deposited metal that has been improved to some extent by ultrasonic vibration. There is a cormorant effect.

Further, since the ultrasonic oscillator is brought into direct contact with the metal wire, there is an advantage that the energy efficiency for peeling the metal deposited on the metal wire is also good. That is, if the ultrasonic oscillator and the metal wire are not in direct contact, the energy generated by the ultrasonic oscillator is transmitted to the metal wire through water, but the ultrasonic wave is generated between the ultrasonic oscillator and water. Since the light is reflected at the interface, the transmittance of ultrasonic waves from the ultrasonic oscillator to water is low. Furthermore, when energy propagates from water to the metal wire, the transmittance of ultrasonic waves is similarly low, so that the energy transmitted from the ultrasonic oscillator to the metal wire is very low.
In this regard, when the ultrasonic oscillator and the metal wire are brought into contact with each other as described above, the ultrasonic wave propagates from the solid to the solid. The reflection of the ultrasonic wave at the contact interface is small, and as a result, the ultrasonic wave transmittance is high and the energy propagation efficiency is also high.

  In addition, when the recovered metal precipitate is composed of a large number of metal wires, the shape of the recovered metal precipitate can be changed according to the concentration of the liquid to be treated in the reactor body by freely changing the assembly of the metal wires. It can be changed freely. Further, in the case where the recovered metal deposit comprises a plurality of wire meshes formed by intersecting a large number of metal wires vertically and horizontally, the flow path of the liquid to be treated in the reactor body is made uniform. There is an effect that can be.

  Further, when the recovered metal precipitate is constituted by a large number of metal wires and the recovered metal precipitate is fixed in the reactor main body, the metal wire is prevented from being accidentally released from the reactor main body. Moreover, since a metal wire will be fixed, the peeling effect of the deposit metal by ultrasonic vibration will increase.

Furthermore, in the case where the recovered metal precipitate is constituted by a large number of metal wires as described above, among the metal wires constituting the recovered metal precipitate, the metal wires constituting the surface in contact with the ultrasonic oscillator are In the case where the metal is made of a metal having a smaller ionization tendency than the metal to be recovered, the metal constituting the metal wire that will be in contact with the ultrasonic oscillator is not eluted into the liquid to be treated. Even if the recovery reaction of the metal to be collected on the wire proceeds, the adhesion between the metal wire and the ultrasonic oscillator is poor, and the ultrasonic oscillator does not inadvertently come off the metal wire.
In addition, since the contact state between the metal wire and the ultrasonic oscillator does not deteriorate, the ultrasonic wave oscillated from the ultrasonic oscillator is reliably transmitted to the metal wire, resulting in a loss of ultrasonic transmission. There is little, and it can suppress that energy efficiency falls large.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
As shown in FIGS. 1 and 2, the metal recovery apparatus of this embodiment includes a vertically long reactor main body 1. This embodiment demonstrates the case where waste liquid is made into object as a to-be-processed liquid. The reactor body 1 is formed so that the cross-sectional area is the same in the entire top and bottom.

  An inflow chamber 7 (not shown) is provided on the lower side of the reactor main body 1 for inflowing waste liquid to be treated, and an upper chamber 9 is provided on the upper side of the reactor main body 1. . The upper chamber 9 is a part for discharging the recovered metal.

  The upper chamber 9 is formed in a shallow cylindrical shape as shown in FIGS. 1 and 2, and the inflow chamber 7 includes a central cylindrical portion 20 and the central cylindrical portion 20 as shown in FIGS. Is formed in a shape including side cylinder portions 21 and 21 provided on the left and right sides.

The upper chamber 9 is composed of an inner cylinder 9a and an outer cylinder 9b as shown in FIG.
As shown in the figure, the upper chamber 9 is attached to the reactor main body 1 by fitting the inner cylinder 9 a to the upper part of the reactor main body 1. A discharge pipe 10 for discharging the recovered flaky or particulate metal is attached to the lower portion of the upper chamber 9 and between the inner cylinder 9a and the outer cylinder 9b. As a result of such a configuration, the liquid to be treated that flows upward in the reactor body 1 overflows from the upper opening of the inner cylinder 9a between the outer cylinder 9b and the inner cylinder 9a, and from the discharge pipe 10 It will be discharged to the outside.

  Further, inflow pipes 8 and 8 are provided on the distal end sides of the side tube portions 21 and 21 of the inflow chamber 7, respectively. Further, two baffle plates 22 and 23 are provided in the longitudinal direction in the side tube portions 21 and 21 of the inflow chamber 7, and the liquid to be treated flowing in from the inflow pipes 8 and 8 is supplied to these baffle plates. The flow is disturbed by 22 and 23 (FIGS. 3 and 4).

Further, a metal wire 2 is accommodated inside the reactor main body 1. More specifically, as shown in FIG. 5, a recovered metal deposit 3 configured in a mesh shape with a large number of metal wires 2 is fixed inside the reactor main body 1. The fixing means is not particularly limited. For example, a means for attaching to the inner wall surface via a fixing member, or a bowl-like body is erected substantially at the center of the reactor body 1, and the recovered metal deposit 3 is placed on the bowl-like body. It is possible to fix by means such as hooking, and various conventionally known fixing means can be employed.

  As shown in FIG. 6, the recovered metal deposit 3 has a plurality of metal meshes 4 formed in a rectangular plate shape by intersecting the metal wires 2 vertically and horizontally, and arranged in parallel at substantially equal intervals. Another wire mesh 4 having the same shape is attached to the upper part of the plurality of wire meshes 4 in a direction orthogonal to the wire mesh 4. The recovered metal deposit 3 is entirely formed in a block-like and three-dimensional mesh shape by the plurality of wire nets 4. Further, among the plurality of wire meshes 4 arranged in parallel, the wire mesh 4 on the end side is formed longer than the other wire meshes 4, and a portion formed longer than the other wire meshes 4 is formed as an extension piece 4a. Has been. By forming the extension piece 4 a in this way, it becomes easy to fix the recovered metal deposit 3 to the reactor body 1. That is, when the recovered metal deposit 3 is attached to the inner wall surface of the reactor main body 1 via the fixing member as described above, a rod-shaped body is erected substantially at the center of the reactor main body 1 and the recovered metal deposit is deposited on the rod-shaped body. Even when any fixing means is employed, such as when the body 3 is hooked, the extension piece 4a as described above is formed, so that the convenience in fixing the recovered metal deposit 3 is improved. Will be illustrated. An ultrasonic oscillator 15 is attached to the side surface of the long wire mesh 4 having the extension piece 4a.

  Furthermore, in addition to the reactor main body 1, the metal recovery apparatus of the present embodiment includes a filter 5 and a pump 6 as shown in FIG. 5. Channels 11, 12, and 13 are provided between the discharge pipe 10 of the reactor main body 1 and the filter 5, between the filter 5 and the pump 6, and between the pump 6 and the inflow pipe 8 of the reactor main body 1, respectively. In FIG. 5, the discharge pipe 10 and the inflow pipe 8 are schematically shown, and the upper chamber 9 and the inflow chamber 7 are not shown.

  In the present embodiment, aluminum (Al) or zinc (Zn) is used as the metal constituting the metal wire 2 of the recovered metal deposit 3, and the recovered metal deposit 3 is a portion to which the ultrasonic oscillator 15 is attached. Copper (Cu) is used in place of the Al or Zn as the metal constituting the surface, that is, the wire mesh 4 on the end side having the extension piece 4a. Further, as a waste liquid to be treated, a flat panel display (FPD) manufacturing factory waste liquid containing indium (In) ions is used. In this case, In is recovered as a metal.

  A method of recovering metal by the metal recovery apparatus having such a configuration will be described. First, waste liquid to be treated flows into the reactor main body 1 from the inflow pipe 8 through the inflow chamber 7. In this case, the inflow chamber 7 is composed of the central cylindrical portion 20 and the side cylindrical portions 21 and 21 as described above, and the side cylindrical portions 21 and 21 are provided with two baffle plates 22 and 23 in the vertical direction. Therefore, the waste liquid flowing in from the inflow pipes 8 and 8 attached to the side cylinder portion 21 in a horizontal direction does not flow in the horizontal direction at once, but the baffle plate 22 provided in the vertical direction, Then, the gas flows into the central cylindrical portion 20 while alternately flowing up and down in the side cylindrical portion 21 along the flow path 23, and flows upward from the central cylindrical portion 20 toward the reactor body 1. Accordingly, the waste liquid flowing in from the inflow pipes 8 and 8 is disturbed by the baffle plates 22 and 23 and is easily circulated upward in the reactor main body 1 without causing a drift. If necessary, for example, a cylindrical basket containing glass or ceramic balls can be installed in the inflow chamber 7, thereby making it possible to prevent drifting more reliably. .

  Then, when the waste liquid flows through the reactor main body 1, a so-called cementation reaction is caused based on a difference in ionization tendency between In contained in the waste liquid and Zn or Al constituting the metal wire 2. This will be described in more detail. The reduction reaction of each metal ion is as follows, and the standard electrode potential (E °) of each metal ion is shown respectively.

In ³⁺ + 3e → In (1) -0.34V
Zn ²⁺ + 2e → Zn (2) −0.76V
Al ³⁺ + 3e → Al (3) -1.66V
Cu ²⁺ + 2e → Cu (4) + 0.34V

As is clear from the above (1) to (4), the standard reduction potential of Zn ²⁺ and Al ³⁺ is smaller than that of In ³⁺ . In other words, the ionization tendency of Zn and Al is larger than that of In. Therefore, due to the circulation of the waste liquid as described above, Zn or Al having a large ionization tendency is eluted as Zn ²⁺ or Al ³⁺ into the waste liquid, and the In ³⁺ contained in the waste liquid is also changed into In and Thus, it is deposited on the surface of Zn or Al particles.

Moreover, although the metal wire which comprises the metal mesh 4 which attaches the ultrasonic oscillator 15 and becomes a contact surface with this ultrasonic oscillator 15 is comprised with Cu, it is clear also from said (1), (4). Thus, the standard reduction potential of Cu ²⁺ is larger than that of In ³⁺ . In other words, the ionization tendency of Cu is smaller than that of In. Therefore, Cu constituting the metal wire does not elute into the waste liquid due to the flow of the waste liquid as described above, and the bonding state between the metal wire 2 and the ultrasonic oscillator 15 becomes poor even when the In precipitation reaction proceeds. Thus, the ultrasonic oscillator 15 is not inadvertently detached from the metal wire 2 constituting the wire mesh 4. As a result, even if the precipitation reaction proceeds, the contact state between the metal wire and the ultrasonic oscillator is not deteriorated, and the ultrasonic wave oscillated from the ultrasonic oscillator 15 is reliably transmitted to the recovered metal precipitate 3. As a result, there is little loss of ultrasonic transmission, and it is possible to suppress a significant decrease in energy efficiency.

After depositing In on the surface of the Zn metal wire or Al metal wire by such a cementation reaction, the ultrasonic oscillator 15 is actuated to provide a long wire mesh on the end side to which the ultrasonic oscillator 15 is attached. 4 is vibrated. As a result, the vibration of the metal mesh 4 on the end side is transmitted to the other metal mesh 4, whereby the entire recovered metal deposit 3 is vibrated. By thus vibrating the recovered metal precipitate 3, the precipitated In is forcibly separated from the metal wire 2 constituting the recovered metal precipitate 3. In this case, the ultrasonic oscillator 15 can be operated continuously. However, if the ultrasonic oscillator 15 is operated continuously, the ultrasonic oscillator generates heat, and it is difficult to operate the ultrasonic oscillator for a long time. There is a fear. In addition, when the ultrasonic oscillator 15 is continuously operated, the deposited metal (In) is sequentially peeled before it grows to a certain size, and as a result, a deposited metal having a certain size cannot be obtained. There is a fear. In this regard, when the ultrasonic oscillator is operated intermittently, there is little risk of inadvertent peeling until the deposited metal becomes large to some extent, so that the separated metal can be easily separated. Therefore, it is preferable to operate the ultrasonic oscillator 15 intermittently. The intermittent operation in this case is performed by, for example, 10 ON, 30 seconds OFF, and the like.

  As described above, as a result of applying the vibration force by the ultrasonic oscillator 15, vibration is transmitted to the entire metal wire 2 constituting the recovered metal precipitate 3, and In deposited on the metal wire 2 is extracted from the metal wire 2. The peeled and peeled In is discharged from the upper chamber 9 through the discharge pipe 10 to the outside of the reactor body 1 and collected.

  In this case, in the present embodiment, the recovered metal deposit 3 for depositing the metal to be recovered is composed of a large number of metal wires 2, so that, for example, cementation is performed compared to the case where zinc scrap is used. The surface area of the metal (Zn or Al) for causing the reaction is increased, and the speed of the In precipitation reaction is improved.

  In addition, after the deposition of the metal that has grown to some extent is recognized, the surface of the new metal wire 2 is always exposed by operating the ultrasonic oscillator 15 as described above to vibrate the wire mesh 4 to maintain the reaction rate. can do. Further, compared to the conventional method of throwing in zinc scrap, the separated deposited metal contains very few impurities other than In.

  Further, since the recovered metal deposit 3 includes a plurality of metal meshes 4 formed by intersecting the metal wires 2 vertically and horizontally and is formed in a mesh shape, the void area of the mesh between the metal wires 2 is the whole. As a result, there is no risk of unevenness in the flow of the liquid to be processed, and the flow path of the liquid to be processed in the reactor main body can be made uniform.

  Further, since the recovered metal deposit 3 is fixedly provided in the reactor main body 1, the metal wire is prevented from being inadvertently released from the reactor main body 1, and the metal wire is fixed. Then, the effect of peeling the deposited metal by ultrasonic vibration is enhanced. Further, since the metal wire is not inadvertently released from the reactor main body 1, it is possible to reduce the mixing of precipitates into the recovered metal.

(Embodiment 2)
In the present embodiment, the type of waste liquid to be processed is different from that in the first embodiment. That is, in this embodiment, the metal surface treatment factory waste liquid containing metal ions such as Cu and Sn is used as the waste liquid. In this respect, in the case of the first embodiment targeting the FPD manufacturing factory waste liquid containing In ions. Is different. As the recovered metal deposit 3 composed of the metal wire 2, the one having the same structure as in the first embodiment is used. The metal wire 2 constituting the recovered metal deposit 3 is made of Zn, and the metal wire 2 constituting the end-side wire mesh 4 to which the ultrasonic oscillator 15 is attached is made of copper (Cu). Things are used. In the present embodiment, since a waste liquid containing metal ions such as Cu and Sn is used, Cu and Sn are recovered as metal.

  Then, a so-called cementation reaction is caused based on a difference in ionization tendency between metals such as Cu and Sn contained in the waste liquid and Zn constituting the metal wire 2. This will be described in more detail. The reduction reaction of Sn ions is as shown in the following formula (5), and the standard electrode potential (E °) is also shown.

Sn ²⁺ + 2e → Sn (5) −0.14V

As is clear from the above formulas (2), (4), and (5), the standard reduction potential of Zn ²⁺ is the smallest compared to Cu ²⁺ and Sn ²⁺ . In other words, the ionization tendency of Zn is the largest compared to Cu and Sn. Therefore, due to the circulation of the waste liquid as described above, Zn having a large ionization tendency becomes Zn ²⁺ (reaction opposite to the above formula (2)) and is eluted in the waste liquid, along with Cu contained in the waste liquid. ²⁺ and Sn ²⁺ become Cu and Sn and are deposited on the surface of the metal wire 2 of Zn.

  Since the action of separating the Cu and Sn thus deposited by the ultrasonic oscillator 15 is the same as that of the first embodiment, detailed description thereof is omitted. The Cu and Sn thus peeled are discharged from the upper chamber 9 through the discharge pipe 10 to the outside of the reactor main body 1 and collected as metal (in this embodiment, an alloy of Cu and Sn). It becomes.

In this embodiment as well, since the metal wire 2 constituting the wire mesh 4 on the end side which is the attachment portion of the ultrasonic oscillator 15 in the recovered metal deposit 3 is made of Cu, the ultrasonic oscillator The metal (Cu) constituting the contact surface with the liquid does not elute into the liquid to be treated, and the ultrasonic oscillator 15 is prevented from being inadvertently detached from the recovered metal precipitate 3, and the adhesion is poor. This also prevents a decrease in ultrasonic energy transmission. That is, in the present embodiment, the type of waste liquid to be processed is different from that in the first embodiment, and Cu ²⁺ and Sn ²⁺ are contained. One of the contained metals is the end portion. It is the same kind of metal (Cu) that constitutes the wire mesh 4 on the side, and the other one Sn ²⁺ is more standard than Cu ²⁺ as is clear from the above formulas (4) and (5). Since the reduction potential is small and, therefore, the ionization tendency of Cu is small compared to Sn, the metal constituting the wire mesh 4 on the end side is not eluted in this embodiment.

(Embodiment 3)
In this embodiment, as shown in FIG. 7, two reactors are provided, and this is different from the case of Embodiments 1 and 2 consisting of only one reactor. That is, in the present embodiment, the filter 17 is provided on the rear side of the first-stage reactor main body 1a and on the front-stage side of the second-stage reactor main body 1b, and further on the rear-stage side of the second-stage reactor main body 1b. 18 is provided. For example, a cartridge filter, a drum filter, or the like is used as the filter. Moreover, it is also possible to use solid-liquid separation means such as a belt press and a filter press in place of the filter.

In this embodiment, for example, when Cu and Sn are contained in the target waste liquid, the first-stage reactor main body 1a is provided with the metal wire 2 made of iron (Fe), and the metal wire 2
Then, Cu is deposited on the first stage filter 17, and the second stage reactor body 1 b is provided with a metal wire 2 made of Zn, and Sn is deposited on the metal line 2 to form the second stage. It is possible to collect Sn with the filter 18.

Here, the metal wire 2 provided in each of the reactor main bodies 1a and 1b constitutes the recovered metal precipitate 3 as in the first and second embodiments, and the configuration of the recovered metal precipitate 3 Is the same as the embodiment. That is, the metal wire 2 constituting the wire mesh 4 on the end side of the recovered metal deposit 3 fixed in the reactor body 1a is made of Cu, and the metal wire 2 constituting the other part is made of Fe. ing. Reactor body 1b
The metal wire 2 constituting the wire mesh 4 on the end side of the recovered metal deposit 3 fixed inside is made of Cu, and the metal wire 2 constituting the other part is made of Zn.

The reduction reaction of iron (Fe) ions and the standard electrode potential are as follows.
Fe ²⁺ + 2e → Fe (6) −0.44V
On the other hand, the reduction reaction and standard electrode potential of Cu and Sn are as shown in the above formulas (4) and (5), and the numerical value of the standard electrode potential is smaller than that of Cu and Sn. Since the ionization tendency is larger than the ionization tendency of Cu or Sn, theoretically, Cu or Sn is deposited on the metal wire 2 made of Fe, but the difference in the ionization tendency is more than the difference between Fe and Sn. The difference between Fe and Cu is much larger. Therefore, in the first-stage reactor main body 1a, Cu is preferentially deposited on the metal wire 2 made of Fe.

  On the other hand, from the numerical value of the standard electrode potential expressed by the above equation (2), the ionization tendency of Zn is larger than the ionization tendency of Cu and Sn. Therefore, in the second-stage reactor body 1b, both Cu and Sn are Zn. However, since Cu has already precipitated on the metal wire 2 made of Fe in the first-stage reactor main body 1a, Sn is mainly contained in the second-stage reactor main body 1b. It is deposited on the metal wire 2 made of Zn. Therefore, in this embodiment, there is an advantage that two kinds of metals can be selectively recovered from the waste liquid using two different kinds of metal wires 2.

  In this embodiment as well, the metal wire 2 constituting the wire mesh 4 to which the ultrasonic oscillator 15 is attached in the recovered metal deposit 3 has a smaller ionization tendency than Sn, which is one of the contained metals in the waste liquid. Since Cu, which is the same kind of metal as the other one-containing metal, is used, it is suitably prevented that the metal constituting the wire mesh 4 of the attachment portion of the ultrasonic oscillator 15 is eluted due to the cementation reaction in the waste liquid. The Rukoto.

(Embodiment 4)
In the present embodiment, as shown in FIG. 8, three reactors are arranged, and in this respect, it is different from the case of the first embodiment consisting of only one reactor or the second embodiment where two reactors are arranged. In the present embodiment, a filter 17, a filter 18, and a filter 19 are provided on the rear side of these three reactor main bodies 1a, reactor main bodies 1b, and reactor main bodies 1c. In the present embodiment, the metal wire 2 made of Fe is provided in the first-stage reactor main body 1a as in the third embodiment, and the metal wire 2 made of Zn is provided in the second-stage reactor main body 1b. The third-stage reactor main body 1c is provided with a metal wire 2 made of Al.

When this embodiment is applied to a waste liquid containing Cu and Sn as in the third embodiment,
In the first-stage reactor main body 1a, Cu is deposited on the metal wire 2 made of Fe as in the third embodiment, and Cu is recovered by the first-stage filter 17, and the second-stage reactor main body 1b is also in the third embodiment. Similarly, Sn is deposited on the metal wire 2 made of Zn, and Sn is recovered by the second-stage filter 18.

  However, in the third-stage reactor main body 1c, an unexpected action occurs from the third embodiment. That is, as described above, Fe eluted by the cementation reaction in the first-stage reactor body 1a and Zn eluted by the cementation reaction in the second-stage reactor body 1b are provided in the third-stage reactor body 1c. It deposits on the metal wire 2 made of Al.

  This point will be described in more detail. Fe constituting the metal wire 2 provided in the first-stage reactor body 1a and Zn constituting the metal wire 2 provided in the second-stage reactor body 1b are: As described above, the ionization tendency is larger than that of the metal to be recovered. From the comparison of the numerical values of the standard electrode potentials expressed by the above formulas (2), (3), and (6), the ionization tendency of Al is Fe, Zn It is clear that this is even greater than the ionization tendency. Accordingly, both Fe eluted from the first-stage reactor body 1a and Zn eluted from the second-stage reactor body 1b are both deposited on the metal wire 2 made of Al by the third-stage reactor body 1c. It is. And it becomes possible to collect | recover as a Fe-Zn alloy with the metal wire 2 which consists of Al.

  Therefore, the work of coagulating and precipitating Fe and Zn eluted from the first-stage reactor main body 1a and the second-stage reactor main body 1b, respectively, becomes unnecessary, and the amount of sludge generated can be suppressed. . In addition, Al elutes in the third-stage reactor body 1c, but trivalent Al needs only a smaller amount of elution than divalent Zn or Fe, the specific gravity of Al is light, and the sludge weight can be reduced. Sludge generation does not increase.

  Furthermore, also in this embodiment, Cu is used for the metal wire 2 which comprises the metal mesh 4 to which the ultrasonic oscillator 15 is attached similarly to each said embodiment. More specifically, the recovered metal precipitate 3 in the first-stage reactor main body 1a is composed of Fe, and the recovered metal precipitate 3 in the second-stage reactor main body 1b is composed of Zn. The recovered metal deposit 3 in the reactor main body 1c is made of Al. However, in any of these three recovered metal precipitates 3, the metal wire 2 constituting the end-side wire mesh 4 is made of Cu. Yes. Therefore, also in this embodiment, the metal constituting the metal mesh 4 of the attachment portion of the ultrasonic oscillator 15 is preferably prevented from eluting due to the cementation reaction in the waste liquid.

(Other embodiments)
In the above-described embodiment, the case where it is applied to an FPD manufacturing factory waste liquid containing In ions as a waste liquid (liquid to be treated) and a metal surface treatment factory waste liquid containing Cu and Sn ions is described. The type of waste liquid to be produced is not limited to this, and can be applied to plating factory waste liquid, semiconductor manufacturing factory waste liquid, and the like. Further, as the liquid to be treated, the main purpose is to use the waste liquid in the present invention, but the liquid to be treated other than the waste liquid, for example, an aqueous solution in which a metal to be recovered is dissolved and ionized using a chemical such as an acid. It is applicable to. In this case, it is of course possible to use a waste liquid as the metal-containing liquid.

  Accordingly, the type of metal to be collected is not limited to In, Cu, and Sn in the embodiment, and for example, Ni, Ga, Zn, and the like can be collected. Absent. Further, the shape of the recovered metal deposit 3 constituted by the metal wire 2 is not limited to the above embodiments, and the shape is not limited. Further, the recovered metal deposit 3 may be fixed to the reactor main body 1 as in the above embodiment, or may be suspended in the liquid to be treated in the reactor main body 1 without being fixed.

  Furthermore, in the above-described embodiment, a plurality of wire meshes 4 formed in a rectangular plate shape by intersecting the metal wires 2 vertically and horizontally are arranged at substantially equal intervals and in parallel, and are in a direction orthogonal to the plurality of wire meshes 4. By attaching another wire mesh 4 having the same shape to the upper part of the plurality of wire meshes 4 and further forming the wire mesh 4 on the end side of the wire meshes 4 longer than the other wire meshes 4, the recovered metal Although the precipitate 3 is configured, the configuration of the recovered metal precipitate 3 is not limited to the embodiment.

  However, when a plurality of wire meshes 4 of the same size are provided as in the embodiment, vibrations from the ultrasonic oscillator 15 are evenly transmitted to the plurality of wire meshes 4, and as a result, the entire recovered metal deposit 3 is obtained. Thus, a preferable effect is obtained in that vibration is efficiently transmitted to the metal, and the separation action of the deposited metal to be collected is improved. Moreover, in this embodiment, since the wire mesh 4 on the end side to which the ultrasonic oscillator 15 is attached is formed longer than the other wire mesh 4, the area of the wire mesh 4 on the end side is formed large. As the area increases, the vibration increases, so that the vibration force of the wire mesh 4 of the oscillation part is efficiently transmitted to the whole.

  Furthermore, in the said embodiment, although the collection | recovery metal deposit 3 was comprised with many metal wires 2, and the collection | recovery object metal was deposited on this collection | recovery metal deposit 3, such a collection | recovery metal deposit 3 is comprised. This is not an essential condition for the present invention. For example, a large number of metal wires 2 may be suspended in the liquid to be treated in the reactor body 1 as they are. In short, the metal wire 2 made of a metal having a higher ionization tendency than the metal to be collected may be accommodated in the reactor main body 1.

  Here, “accommodates” means that the recovered metal precipitate 3 is constituted by the metal wire 2 and fixed to the reactor main body 1 as described above, or the recovered metal precipitate 3 is configured and formed in the reactor main body 1. Floating in the liquid to be treated, or the metal wire 2 forms the wire mesh 4 and floats in the liquid to be treated in the reactor main body 1, or floats in the liquid to be treated in the reactor main body 1 in the state of the metal wire 2. It is meant to include widely. Therefore, the metal wire 2 may be fixedly accommodated before the liquid to be treated flows into the reactor main body 1, or may be accommodated at the same time as the liquid to be treated flows. The metal wire 2 may be added and accommodated after the processing liquid is introduced.

  Furthermore, in the said embodiment, although the ultrasonic oscillation body 15 was attached to the side surface side of the metal mesh 4 of the edge part among the several metal meshes 4 which comprise the collection | recovery metal deposits 3, the place which attaches the ultrasonic oscillation body 15 Is not limited to this embodiment. For example, the extension piece 4 a may be attached to the upper end portion or the lower end portion, and the ultrasonic oscillator 15 is attached to the wall surface of the reactor main body 1, and the tip end side of the ultrasonic oscillator 15 is connected to the interior of the reactor main body 1. And the tip of the protruding ultrasonic oscillator 15 is brought into contact with the recovered metal deposit 3 or the metal mesh 4 made of the metal wire 2 or in contact with the metal wire 2 itself. It is also possible. In short, it is sufficient that the ultrasonic oscillator 15 is provided in contact with the metal wire 2.

  Further, the frequency of the ultrasonic wave oscillated from the ultrasonic oscillator 15 is not particularly limited, but a frequency of 20 kHz or more and several MHz or less can be suitably used. This is because if it is 20 kHz or less, there is a problem of noise, and if it is several MHz or more, the attenuation becomes high and energy may be lost.

  Furthermore, in the said embodiment, although Cu was used for the metal wire 2 which comprises the metal mesh 4 used as the contact surface of the collection | recovery metal deposit 3 to which the ultrasonic oscillator 15 is attached, it is not restricted to this, For example, stainless steel and various metals An alloy or the like can also be used. In short, any metal wire 2 constituting the contact surface with the ultrasonic oscillator 15 can be used as long as it has a smaller ionization tendency than the metal to be collected.

In addition, by using a metal having a smaller ionization tendency than the metal to be collected as a constituent member of the metal wire 2 that constitutes the contact surface with the ultrasonic oscillator 15 as described above, the metal is coated by the cementation reaction as described above. A preferable effect is obtained that the ultrasonic oscillator 15 can be prevented from being carelessly detached without being deposited in the treatment liquid, but only the metal wire 2 constituting the contact surface with the ultrasonic oscillator 15 is thus obtained. It is not an essential matter of the present invention to use a metal different from the metal wire 2 of the other part and a metal having a smaller ionization tendency than the metal to be collected,
You may use the same kind of metal as the metal wire 2 of another part. Therefore, the recovered metal deposit 3 may be entirely composed of the same metal.

Further, in the present embodiment, the extension piece 4a is provided on the wire mesh 4 that constitutes the contact surface with the ultrasonic oscillator 15 so as to be easily fixed in the reactor main body 1, but the present invention is not limited thereto.
The plurality of wire meshes 4 may all be the same length.

  Furthermore, in the present embodiment, the metal wire uses a single metal, but may be an alloy. As the alloy, an iron-aluminum alloy, a calcium-silicon alloy, or the like can be used.

  Furthermore, in the first embodiment, the reactor main body 1 is formed so that the cross-sectional areas thereof are substantially the same. However, the formation of the reactor main body 1 is not an essential condition for the present invention. For example, the reactor main body 1 It is also possible to form such that the cross-sectional area increases toward the top of 1.

The schematic perspective view of the collection | recovery apparatus of the metal as one Embodiment. The schematic sectional drawing of the collection | recovery apparatus of the metal of the embodiment. The schematic plan view of the chamber for inflow in the metal collection | recovery apparatus of the embodiment. AA line expanded sectional view of FIG. The schematic block diagram of the metal collection | recovery apparatus of the embodiment. The perspective view which shows the collection | recovery metal deposit. The schematic block diagram of the metal collection | recovery apparatus of other embodiment. The schematic block diagram of the metal collection | recovery apparatus of other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c ... Reactor main body 2 ... Metal wire 3 ... Collected metal deposit 4 ... Wire mesh 15 ... Ultrasonic oscillator

Claims (10)

  A liquid to be treated containing the metal to be recovered in an ionic state flows into the reactor body, and a metal wire (2) made of a metal having a higher ionization tendency than the metal to be recovered is accommodated in the reactor body. The state in which the metal contained in the liquid to be treated is deposited on the surface of the metal wire (2) due to the difference in ionization tendency, and then the ultrasonic oscillator (15) is brought into contact with the metal wire (2). Then, the metal wire (2) is vibrated by the ultrasonic oscillator (15), and the deposited metal is peeled off from the metal wire (2) and recovered.   The method for recovering a metal according to claim 1, wherein the recovered metal precipitate (3) is constituted by a number of metal wires (2).   The metal recovery method according to claim 2, wherein the recovered metal deposit (3) comprises a plurality of metal meshes (4) configured by intersecting a number of metal wires (2) vertically and horizontally.   The metal recovery method according to claim 2 or 3, wherein the recovered metal deposit (3) is fixed in the reactor main body.   Among the metal wires (2) constituting the recovered metal precipitate (3), the metal wire (2) constituting the surface in contact with the ultrasonic oscillator (15) has a smaller ionization tendency than the metal to be recovered. The metal recovery method according to any one of claims 2 to 4, comprising:   Into the liquid to be treated containing the metal to be recovered in an ionic state, the metal wire (2) made of a metal having a higher ionization tendency than that of the metal to be recovered is accommodated, In order to recover the metal deposited on the metal wire (2), the reactor main body (1) for performing a metal deposition reaction for depositing the metal contained in the treatment liquid on the surface of the metal wire (2), An apparatus for recovering metal, comprising: an ultrasonic oscillator (15) for contacting the metal wire (2) to separate the deposited metal from the metal wire (2).   The metal recovery device according to claim 6, wherein the recovered metal deposit (3) is constituted by a large number of metal wires (2).   8. The metal recovery apparatus according to claim 7, wherein the recovered metal deposit (3) comprises a plurality of metal meshes (4) formed by intersecting a number of metal wires (2) vertically and horizontally.   The metal recovery device according to claim 7 or 8, wherein the recovered metal deposit (3) is fixed in the reactor main body (1).   Among the metal wires (2) constituting the recovered metal precipitate (3), the metal wire (2) constituting the surface in contact with the ultrasonic oscillator (15) has a smaller ionization tendency than the metal to be recovered. The metal recovery device according to any one of claims 7 to 9, comprising:

Images