JP2017100094A - Heavy metal separation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heavy metal separation system for inexpensively and efficiently separating-recovering heavy metal in a processing object by using magnetic powder.SOLUTION: This heavy metal separation system 100 comprises a first tank 30 for separating a heavy metal component from a processing object by eluting in a supernatant liquid, a second tank 40 for mixing-agitating magnetic powder in the supernatant liquid of including the heavy metal component, a magnet part 60 for transferring the heavy metal component by including the magnetic powder by a bar-shaped magnet 62, a third tank 50 for eliminating an adsorption state of the magnetic powder and the heavy metal component by an acid solution, and a magnetic powder recovery part 70 for separating the heavy metal component and the magnetic powder, and these functionally operate, so that heavy metal in the processing object such as incinerated ash can be inexpensively and efficiently separated-recovered.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heavy metal separation system that separates heavy metal components contained in an object to be treated such as waste incineration ash, sewage treatment sludge, and sewage.

  Household waste and industrial waste incinerated ash, sewage treatment sludge, other waste sludge, sewage, and the like may contain heavy metals such as zinc, copper, manganese, lead, cadmium, and chromium. And these heavy metals may adversely affect the natural environment and health, and it is not preferable to use them for landfill and reuse as they are. For this reason, for example, incinerated ash containing heavy metals is treated by a cement solidification method, a melt solidification method, or the like. However, in cement solidification, heavy metal components may be eluted by acid rain in recent years. In addition, melt solidification is expensive due to high temperature treatment, and some heavy metals volatilize. Regarding these problems, the following [Patent Document 1] discloses an invention relating to a method for separating and recovering heavy metal components using magnetic powder.

Japanese Patent No. 486718

  However, [Patent Document 1] only describes a method for separating and recovering heavy metal components using magnetic powder, and there is no specific description regarding a system configuration for efficiently separating and recovering heavy metal components at low cost. .

  This invention is made | formed in view of the said situation, and it aims at providing the heavy metal separation system which isolate | separates and collects the heavy metal in a process target object at low cost using magnetic powder.

The present invention
(1) a first tank 30 provided with stirring means 32 and stirring a processing object containing a heavy metal component in water;
A first settling tank 34 provided below the first tank 30;
First opening / closing means 36 for opening / closing between the first sedimentation tank 34 and the first tank 30;
A first discharge part for discharging the precipitate in the first settling tank 34;
A delivery means for delivering the supernatant liquid in the first tank 30;
A second tank 40 provided with stirring means 42 and stirring the supernatant liquid and magnetic powder delivered from the delivery means;
A magnet part 60 that can be put in and out of the second tank 40 and magnetizes the magnetic powder together with heavy metal components;
Transfer means 66 for transferring the magnet part 60;
A second settling tank 44 provided below the second tank 40;
Second opening and closing means 46 for opening and closing between the second sedimentation tank 44 and the second tank 40;
A second discharge part for discharging the precipitate in the second settling tank 44;
A third tank 50 in which the magnet unit 60 can be taken in and out;
Demagnetizing means 80 for releasing the magnetic adhesion of the magnet part 60 and dropping the magnetic powder together with the heavy metal component into the acidic solution in the third tank 50;
A third settling tank 54 provided below the third tank 50;
Third opening and closing means 56 for opening and closing between the third sedimentation tank 54 and the third tank 50;
A third discharger for discharging the magnetic powder precipitated in the third settling tank 54 together with heavy metal components;
A magnetic powder recovery unit 70 for separating the magnetic powder from the precipitate discharged by the third discharge unit,
The magnet unit 60 includes a plurality of bar-shaped magnets 62 and a holding unit 64 that fixes the plurality of bar-shaped magnets 62 in a vertical direction with a predetermined gap therebetween. This solves the above problem.
(2) The rod-shaped magnet 62 is provided up to a position of 80% to 90% of the inner dimension of the second tank 40, and is arranged and fixed at equal intervals of 5 cm to 10 cm. The above problem is solved by providing the heavy metal separation system 100.
(3) The rod-shaped magnet 62 is a permanent magnet having a magnetized surface on the side surface,
The demagnetizing means 80 includes a sheath tube 82 into which the rod-shaped magnet 62 can be inserted, and an attaching / detaching mechanism 84 for inserting and removing the sheath tube 82 from the rod-shaped magnet 62.
The magnetic powder in the second layer 40 is magnetically deposited on the surface of the sheath tube 82 together with the heavy metal components in the state where the rod-shaped magnet 62 is housed in the sheath tube 82, and is immersed in an acidic solution in the third tank 50. The heavy metal separation system 100 according to (1) or (2) above, wherein the magnetism is released by pulling out the rod-shaped magnet 62 from the sheath tube 82 and the magnetic powder is dropped into the third tank 50. By providing the above, the above-described problems are solved.
(4) The heavy metal separation according to (1) or (2) above, wherein the rod-shaped magnet 62 is an electromagnet, and the degaussing means 80 is a switch mechanism 88 for turning on / off the energization of the rod-shaped magnet 62. By providing the system 100, the above problem is solved.
(5) In the above (1) to (4), the stirring means 32, 42 of the first tank 30 and the second tank 40 are pulsator-type dish-shaped impellers provided in the lower part of the tank. By providing the heavy metal separation system 100 according to any one of the above, the above-described problems are solved.
(6) Floating substance recovery piping 58 for recovering levitated material containing inorganic silicon floating in the third tank 50 is provided in the vicinity of the liquid surface of the third tank 50. (1) to (5) By providing the heavy metal separation system 100 according to any one of the above, the above-described problems are solved.

  According to the heavy metal separation system according to the present invention, it is possible to efficiently separate and recover heavy metals using magnetic powder with respect to a processing object such as incineration ash.

1 is a schematic configuration diagram of a heavy metal separation system according to the present invention. It is a figure explaining the magnet part of the heavy metal separation system which concerns on this invention. It is a figure which shows the example of the demagnetizing means of the heavy metal separation system which concerns on this invention.

  An embodiment of a heavy metal separation system according to the present invention will be described with reference to the drawings. A heavy metal separation system 100 according to the present invention shown in FIG. 1 includes a first tank 30 that stirs an object to be processed containing heavy metal in water, and a supernatant liquid from the first tank 30 that is taken and mixed and stirred with magnetic powder. Two tanks 40, a magnet unit 60 that transfers the heavy metal component in the magnetic powder mixed water in the second tank 40 to the third tank 50 together with the magnetic powder, and a third tank 50 that separates the magnetic powder and the heavy metal component, And a magnetic powder recovery unit 70 for separating the magnetic powder from the precipitate separated in the third tank 50.

  In addition, the first tank 30 has a stirring means 32 in the lower part, and the lower side is a funnel-shaped hopper part 30a. And the 1st sedimentation tank 34 is provided in the tip of this hopper part 30a via the 1st opening-and-closing means 36. As shown in FIG. The first settling tank 34 is preferably provided with an observation window 38a that allows the state of precipitation to be visually observed or a detection means 38b such as a turbidity sensor that detects the state of precipitation. Further, a first discharge part having a discharge valve 10a, a pump means 18 and a discharge pipe 12a is connected to the front side of the first settling tank 34. In addition, since the deposit in the first tank 30 is generally high in concentration and low in water content, it is preferable to use a vacuum pump or the like as the pump means 18 of the first discharge unit that is less likely to be clogged. Further, the first tank 30 is connected to a delivery means including a delivery pipe 20 for delivering the supernatant liquid in the first tank 30, an on-off valve 20a, and a pump means 20b. In addition, when a processing target object is incineration ash, the liquid mixture of a processing target object and water shows alkalinity. Therefore, these members are preferably made of an alkali-resistant material or subjected to an alkali-resistant surface treatment from the viewpoint of preventing aging of the apparatus.

  Moreover, the 2nd tank 40 has the stirring means 42 in the lower part similarly to the 1st tank 30, and the lower side is the funnel-shaped hopper part 40a. As the stirring means 42 and the stirring means 32 of the first tank 30, it is preferable to use a pulsator-type dish-shaped impeller. According to this configuration, in addition to easy maintenance such as cleaning, the magnet unit 60 can be taken in and out of the tank while stirring in the second tank 40 in particular, and the magnetic powder can be transferred efficiently. Can do. Further, a second settling tank 44 is provided at the tip of the hopper portion 40a through a second opening / closing means 46. And the 2nd discharge part which has the discharge valve 10b and the discharge piping 12b connects to the front side of the 2nd sedimentation tank 44. FIG. The second tank 40 includes a water supply pipe 14 for supplying predetermined water into the tank, a return pipe 16 that includes an on-off valve 16a and a pump means 16b, and sends the residual water after separation of the magnetic powder to the first tank 30. Is connected.

  Further, the lower side of the third tank 50 is also a funnel-shaped hopper portion 50 a, and a third sedimentation tank 54 is provided on the front side of the hopper portion 50 a via a third opening / closing means 56. Further, a third discharge part having a discharge valve 10c, a pump means 19, and a discharge pipe 12c is connected to the front side of the third settling tank 54. Further, the third tank 50 is provided with an open / close valve 22a and an acidic solution discharge pipe 22 for collecting the acidic solution in the tank, and a floating substance provided near the liquid surface and including an open / close valve 58a and containing inorganic silicon or the like. A floating substance recovery pipe 58 to be recovered is connected. Here, inorganic silicon refers to inorganic silicic acid, inorganic silicon compounds, and the like. Further, since the acidic solution is stored in the third tank 50, it is preferable that these members and the like are subjected to an acid-resistant material or an acid-resistant surface treatment from the viewpoint of preventing deterioration of the apparatus over time.

  The first opening / closing means 36, the second opening / closing means 46, the discharge valves 10a, 10b, and the opening / closing valves 20a, 16a have the same diameters as the pipes to be connected, and use electromagnetic valves that open and close by manual and electrical control. Is preferred. The third opening / closing means 56, the discharge valve 10c, and the opening / closing valves 22a and 58a are preferably inexpensive manual valves.

  The magnet unit 60 includes a plurality of bar magnets 62 and a holding unit 64 that fixes the plurality of bar magnets 62 in a vertical direction with a predetermined gap therebetween. It moves between 40 and the 3rd tank 50. Further, the magnet unit 60 can be moved in the vertical direction within a predetermined range by the transfer means 66, whereby the magnet unit 60 can be taken in and out of the second tank 40 and the third tank 50.

  Here, the preferable structure and external dimension of the magnet part 60 are demonstrated using FIG. Here, FIG. 2A is a schematic plan view of the state in which the magnet unit 60 is placed in the second tank 40, and FIG. 2B is a schematic side view. 2A and 2B, the bar-shaped magnet 62 has a predetermined length, and is fixed so that the upper end side is fixed to the holding portion 64 and hangs downward. The magnet used for the rod-shaped magnet 62 is not particularly limited, and a permanent magnet such as a well-known ferrite magnet or rare earth magnet, or an electromagnet can be used. Further, the diameter of the rod-shaped magnet 62 is not particularly limited, and it is preferable to use one having a diameter of about 50 mm. Furthermore, it is preferable from the viewpoint of the collection efficiency of the magnetic powder that the rod-shaped magnets 62 are inserted almost uniformly throughout the second tank 40. Therefore, the distance L1 between the rod-shaped magnets 62 located at the outermost parts of the magnet part 60 is 80% to the inner diameter dimension of the second tank 40 (inner dimensions of each side when the second tank 40 is rectangular) L2. 90% is preferable. Further, the number of the bar-shaped magnets 62 to be installed on the holding portion 64 and the interval between them are set as appropriate according to the magnetic force of the bar-shaped magnets 62. Arrange sparsely. However, in the case of a general bar-shaped magnet 62, it is preferable to arrange and fix the holding portions 64 at regular intervals in a range of approximately 5 cm to 10 cm. In addition, when using a permanent magnet for the rod-shaped magnet 62, it is preferable from the surface of the collection efficiency of a magnetic powder to use the magnet of the radial direction magnetization in which the side surface with a large area functions as a magnetized surface. When the radially magnetized rod-shaped magnet 62 is used, it is preferable to immerse the rod-shaped magnet 62 as deeply as possible in the second tank 40. Therefore, the length of the bar-shaped magnet 62 is preferably longer than the distance T from the upper position of the hopper portion 40a to the liquid level. Moreover, when the rod-shaped magnet 62 is an electromagnet, the length by which the end surface which is a magnetized surface is located in the middle of the 2nd tank 40 is preferable. Moreover, you may make it arrange | position the rod-shaped magnet 62 of different length so that the end surface which is a magnetic attachment surface may be distributed in the 2nd tank 40 whole.

  Moreover, the magnet part 60 is provided with a demagnetizing means 80 for releasing the magnetic adhesion of the magnetic powder. Here, an example of the demagnetizing means 80 is shown in FIG. First, as the demagnetizing means 80 when the rod-shaped magnet 62 is a permanent magnet, as shown in FIG. 3A, the same number of rod-shaped magnets 62 are arranged and fixed at the same position, the rod-shaped magnets 62 can be inserted, and the magnet itself is magnetic. It is preferable to include a sheath tube 82 that does not have the structure and an attachment / detachment mechanism 84 that inserts and removes the sheath tube 82 from the rod-shaped magnet 62. Further, as shown in FIG. 3B, the demagnetizing means 80 in the case where the bar magnet 62 is an electromagnet is preferably a switch mechanism 88 for turning on / off the energization to the coil 86 that excites the bar magnet 62. . In addition, since the rod-shaped magnet 62 and the sheath tube 82 of the electromagnet are immersed in the acidic solution in the third tank 50, it is preferable to perform acid-resistant material or acid-resistant surface treatment.

  The magnetic powder recovery unit 70 includes a receiving tank 72 that receives the precipitate in the third tank 50 discharged from the discharge pipe 12c, and magnetic powder separation means 74 that separates and recovers the magnetic powder in the precipitate. Yes. As the magnetic powder separating means 74, a known permanent magnet, an electromagnet, a known filter, or the like can be used. When a permanent magnet is used for the magnetic powder separating means 74, a demagnetizing means such as a sheath tube or a cover plate is provided. In the case of an electromagnet, a switch for turning on / off energization of the coil for exciting the magnetic powder separating means 74 is provided. It is preferable to provide a mechanism.

  Next, the operation of the heavy metal separation system 100 according to the present invention will be described. First, in a state where the first opening / closing means 36 and the opening / closing valve 20a are closed, a predetermined amount of a processing object such as incineration ash, sewage treatment sludge, and sewage is put into the first tank 30. Any method such as pressure feeding, dropping by a belt conveyor, a hopper, or the like may be used as a method for loading the processing object.

  Next, water is supplied to the first tank 30. At this time, the supplied water is preferably used after adjusting the residual water after separation of the magnetic powder in the second tank 40 to a pH of about 7-8. In this case, the on-off valve 16a on the second tank 40 side is opened by electrical control or manually, the pump means 16b is activated, and the residual water in the second tank 40 is supplied to the first tank 30 through the reflux pipe 16. . Moreover, when residual water is insufficient, city water or industrial water may be supplied from a water supply pipe (not shown). Further, when the object to be treated is sewage, these waters are appropriately supplied according to the concentration of sewage. In addition, when a process target object is incineration ash, it is preferable that the amount of water supply shall be about 4 to 5 times the weight of a process target object in general.

  When water and the processing object are put into the first tank 30, the stirring means 32 operates to stir the processing object in water. The rotation speed and stirring time of the stirring means 32 at this time are approximately 30 minutes at approximately 200 rpm to 3000 rpm, although depending on the capacity of the first tank 30, the type and amount of the object to be treated, the amount of water, the ability of the stirring means 32, and the like. It is preferable to do. In addition, when a process target object is incineration ash, the mixed water with a process target object becomes alkaline. And the heavy metal component in a process target object melt | dissolves in this mixed water by this stirring.

  Next, the stirring means 32 is stopped, and the first opening / closing means 36 is opened by electrical control or manually. At this time, the discharge valve 10a is in a closed state. And it leaves still for 3min-60min in this state. As a result, the object to be treated is deposited in the first sedimentation tank 34 through the first opening / closing means 36 in the open state. The state of sedimentation of the processing object is monitored by visual observation through the observation window 38a or by the detection means 38b. When it is determined that the object to be treated has sufficiently settled in the first settling tank 34, the first opening / closing means 36 is closed by electrical control or manually. Then, after opening the discharge valve 10a of the first discharge part by electric control or manually, the pump means 18 is started. Thereby, the processing object which settled in the 1st sedimentation tank 34 is discharged | emitted to a predetermined tank through the discharge piping 12a of a 1st discharge part. In addition, since the heavy metal component, minerals, such as inorganic silicon, salts, etc. which are contained in the processing object are eluted in the supernatant liquid in the 1st tank 30, the processing object which settled contains these components almost. In particular, heavy metal components are below the standards of the Ministry of the Environment. Therefore, the processing object discharged by the first discharge unit can be subjected to predetermined landfill processing or the like, and can be reused as a material for cement or concrete block in the case of incinerated ash, for example.

  After the first opening / closing means 36 is closed, the opening / closing valve 20a of the delivery means is opened by electric control or manually, and the pump means 20b is activated. At this time, the second opening / closing means 46 and the opening / closing valve 16a of the second tank 40 are closed. Thereby, the supernatant liquid of the first tank 30 in which the heavy metal component and the like are dissolved is sent to the second tank 40 through the delivery pipe 20. When the delivery of the supernatant liquid is completed, the on-off valve 20a is closed and the pump means 20b is stopped.

  Next, city water or industrial water is supplied from the water supply pipe 14 to the supernatant liquid sent to the second tank 40, and thereby the pH of the supernatant liquid is adjusted to neutral. Next, a predetermined amount of magnetic powder is introduced into the supernatant liquid whose pH has been adjusted, and the stirring means 42 is activated to mix and stir the supernatant liquid and the magnetic powder. The stirring time by the stirring means 42 is approximately 10 minutes, although it depends on the capacity of the second tank 40 and the capacity of the stirring means 42. In addition, as the magnetic powder used at this time, any powder such as a magnetic oxide powder such as ferrite or magnetite, a magnetic metal powder, or the like may be used. The average particle size of the magnetic powder is preferably 100 μm or less, particularly preferably 10 nm to 500 nm. Further, the amount of magnetic powder input is preferably 1 wt% to 100 wt%, particularly preferably about 10 wt%, with respect to the weight of the object to be processed. In addition, as a manufacturing method of magnetic powder, well-known manufacturing methods, such as a wet oxidation method, can be used. And the heavy metal component melt | dissolved in the supernatant liquid precipitates when pH is adjusted to neutrality, and it adsorb | sucks to magnetic powder by an electrical attractive force etc. Moreover, when inorganic silicon exists in a supernatant liquid, this also adsorb | sucks to magnetic powder. In addition, the adsorption | suction power of a magnetic powder and a heavy metal component increases by adjusting pH to neutrality.

  Next, while lowering the rotation speed of the stirring means 42 and stirring to such an extent that magnetic powder does not accumulate on the bottom of the second tank 40, the transfer means 66 is operated to bring the magnet unit 60 into the magnetic powder mixed water in the second tank 40. Immerse. As a result, the magnetic powder adheres to the magnetized surface of the rod-shaped magnet 62 or the surface of the sheath tube 82 while adsorbing the heavy metal component and the like.

  Next, the transfer means 66 takes out the magnet part 60 from the second tank 40, moves it onto the third tank 50, and immerses it in the third tank 50. At this time, the third opening / closing means 56 is open, and the discharge valve 10c and the opening / closing valves 22a, 58a are closed. A predetermined acidic solution is stored in the third tank 50. As the acid used in the acidic solution, inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid are preferable, and it is particularly preferable to dilute nitric acid with about 4 times water.

  Next, the demagnetizing means 80 is operated to release the magnetic adhesion of the magnetic part 60. For example, in the demagnetizing means 80 using the sheath tube 82 shown in FIG. 3A, the magnet unit 60 is raised while holding the attaching / detaching mechanism 84 and immersing the sheath tube 82 in the acidic solution of the third tank 50. Thereby, the rod-shaped magnet 62 is extracted from the inside of the sheath tube 82, and the magnetic adhesion of the magnetic powder on the surface of the sheath tube 82 is released. Thereby, magnetic powder, heavy metal components, etc. are dropped into the acidic solution in the third tank 50. The sheath tube 82 from which the magnetic powder has fallen is raised by the attaching / detaching mechanism 84, taken out from the third tank 50, and worn on the rod-shaped magnet 62. Further, in the demagnetizing means 80 for the rod-shaped magnet 62 composed of the electromagnet shown in FIG. 3B, the switch mechanism 88 is turned off while the rod-shaped magnet 62 is immersed in the acidic solution. Thereby, the energization to the coil 86 that excites the bar magnet 62 is stopped, and the magnetic adhesion of the magnetic powder is released. Thereby, magnetic powder, heavy metal components, etc. are dropped into the acidic solution in the third tank 50. Thereafter, the magnet unit 60 is taken out from the third tank 50 by the transfer means 66. Then, the switch mechanism 88 is turned on, and the bar magnet 62 functions again as a magnet.

  The transfer of the magnetic powder and heavy metal components from the second tank 40 to the third tank 50 by the magnet unit 60 is repeated 5 to 6 times until there is no magnetic powder magnetically attached to the rod-shaped magnet 62. The magnetic powder and heavy metal components that have fallen into the third tank 50 are separated from the adsorbed state by the acidic solution.

  In addition, for example, a predetermined amount of calcium-based coagulant is added to the residual water in the second tank 40 to which the magnetic powder has been transferred by the magnet unit 60. As a result, the salts remaining in the residual water are solidified as calcium chloride, for example. When the salt or the like is solidified, the stirring means 42 is stopped and the second opening / closing means 46 is opened by electric control or manually. At this time, the discharge valve 10b is in a closed state. And it leaves still in this state. Thereby, aggregates, such as salts, precipitate in the 2nd sedimentation tank 44 through the 2nd opening-and-closing means 46 in an open state. Then, after a predetermined time has passed and the aggregate has sufficiently settled in the second settling tank 44, the second opening / closing means 46 is closed by electrical control or manually. Next, the discharge valve 10b of the second discharge unit is opened by electrical control or manually. Thereby, the aggregate which settled in the 2nd sedimentation tank 44 is discharged | emitted by the predetermined tank through the discharge piping 12b of a 2nd discharge part. The discharged agglomerates are subjected to appropriate treatment according to the substance. The residual water from which aggregates such as salts have been separated and removed is appropriately supplied to the first tank 30 through the reflux pipe 16 by the on-off valve 16a and the pump means 16b as described above and reused. At this time, the residual water is diluted with tap water (city water) or industrial water to adjust the pH to a neutral level.

  Further, the magnetic powder and heavy metal components transferred to the third tank 50 are allowed to stand in an acidic solution for about 24 hours. As a result, the magnetic powder and the heavy metal component are precipitated in the third settling tank 54 through the third opening / closing means 56 in the open state. In addition, inorganic silicon or the like floats on the surface of the third tank 50 with bubbles. When a predetermined time has passed and the magnetic powder and heavy metal components have sufficiently settled in the third settling tank 54 and inorganic silicon or the like has floated, the third opening / closing means 56 is closed and the discharge valve 10c of the third discharge section. Is opened and the pump means 19 is started. As a result, the magnetic powder and heavy metal components precipitated in the third settling tank 54 are discharged to the receiving tank 72 of the magnetic powder collecting section 70 through the discharge pipe 12c of the third discharge section. At the same time, the on-off valve 58a is opened and a pump means (not shown) connected to the floating substance recovery pipe 58 is activated. Thereby, the levitated material containing inorganic silicon is discharged to the predetermined tank through the levitated substance recovery pipe 58. The discharged levitated matter is subjected to appropriate treatment according to the substance. In addition, the acid solution from which the precipitate and the floating matter are discharged is reused as it is, and is appropriately collected through the acid solution discharge pipe 22.

  The magnetic powder and heavy metal components discharged to the receiving tank 72 are separated by the magnetic powder separation means 74. Here, when a magnet is used for the magnetic powder separation means 74, the magnetic powder separation means 74 is brought close to or in contact with the magnetic powder and heavy metal components discharged to the receiving tank 72. Thereby, magnetic powder is magnetically attached to the magnetic powder separating means 74. The separation of the magnetic powder may be performed by a wet method, or may be performed by a dry method after drying. Since the magnetic powder and the heavy metal component are separated by the acidic solution, only the magnetic powder is magnetically attached to the magnetic powder separating means 74, and other heavy metal components and the like remain on the receiving tank 72 side. The magnetic powder magnetically attached to the magnetic powder separation means 74 is dropped from the magnetic powder separation means 74 by the demagnetization means of the magnetic powder separation means 74 and collected. The collected magnetic powder is appropriately washed with water, dried and reused. The heavy metal component remaining in the receiving tank 72 is separated and reused for each substance by appropriate disposal or a known method.

  As described above, the heavy metal separation system 100 according to the present invention mixes and stirs magnetic powder in the first tank 30 that elutes the heavy metal component into the supernatant liquid and separates it from the processing target, and the supernatant liquid containing the heavy metal component. The second tank 40, the magnet part 60 for transferring the heavy metal component together with the magnetic powder by the rod-shaped magnet 62, the third tank 50 for eliminating the adsorption state of the magnetic powder and the heavy metal component by the acidic solution, the heavy metal component and the magnetic powder. And a magnetic powder recovery unit 70 that separates and collects heavy metals in a processing object such as incineration ash at low cost and efficiently.

  It should be noted that the configuration, shape, operation, conditions, piping route, etc. of each part of the heavy metal separation system 100 shown in this example are examples, and the present invention can be modified and implemented without departing from the scope of the present invention. Is possible.

30 1st tank
32, 42 Stirring means
34 First sedimentation tank
36 First opening / closing means
40 Second tank
44 Second sedimentation tank
46 Second opening / closing means
50 3rd tank
54 Third sedimentation tank
56 Third opening / closing means
58 Floating substance recovery piping
60 Magnet part
62 Bar magnet
64 Holding part
66 Transfer means
70 Magnetic powder recovery unit
80 Degaussing means
82 sheath tube
84 Detachment mechanism
88 Switch mechanism
100 Heavy metal separation system

Claims (6)

A first tank that is equipped with a stirring means and stirs a processing object containing a heavy metal component in water;
A first settling tank provided below the first tank;
First opening and closing means for opening and closing between the first sedimentation tank and the first tank;
A first discharger for discharging the precipitate in the first settling tank;
A delivery means for delivering the supernatant liquid in the first tank;
A second tank comprising stirring means and stirring the supernatant liquid and magnetic powder sent from the sending means;
A magnet part that can be put in and out of the second tank and magnetizes the magnetic powder together with the heavy metal component;
Transfer means for transferring the magnet part;
A second settling tank provided below the second tank;
Second opening and closing means for opening and closing between the second sedimentation tank and the second tank;
A second discharger for discharging the precipitate in the second settling tank;
A third tank in which the magnet part can be taken in and out;
Demagnetization means for releasing the magnetic adhesion of the magnet part and dropping the magnetic powder together with the heavy metal component into the acidic solution in the third tank;
A third settling tank provided below the third tank;
Third opening and closing means for opening and closing between the third precipitation tank and the third tank;
A third discharger for discharging the magnetic powder precipitated in the third settling tank together with the heavy metal component;
A magnetic powder recovery unit for separating the magnetic powder from the precipitate discharged by the third discharge unit,
The magnet part has a plurality of bar magnets and a holding part for arranging and fixing the plurality of bar magnets in a vertical direction with a predetermined gap. 2. The heavy metal separation system according to claim 1, wherein the bar-shaped magnets are provided up to a position of 80% to 90% of the inner dimension of the second tank, and are arranged and fixed at equal intervals of 5 cm to 10 cm. The rod-shaped magnet is a permanent magnet having a magnetically attached surface on its side surface,
The demagnetizing means has a sheath tube into which the rod-shaped magnet can be inserted, and an attaching / detaching mechanism for inserting and removing the sheath tube from the rod-shaped magnet,
The magnetic powder in the second layer is magnetically deposited on the surface of the sheath tube together with the heavy metal components in the state where the rod-shaped magnet is housed in the sheath tube, and the rod-shaped magnet from the sheath tube is immersed in the acidic solution in the third tank. The heavy metal separation system according to claim 1, wherein the magnetic powder is released by removing the magnetic powder and the magnetic powder is dropped into the third tank. 3. The heavy metal separation system according to claim 1, wherein the bar magnet is an electromagnet, and the demagnetizing means is a switch mechanism that turns on and off the energization of the bar magnet. The heavy metal separation system according to any one of claims 1 to 4, wherein the stirring means of the first tank and the second tank is a pulsator-type dish-shaped impeller provided at a lower portion of the tank. The heavy metal according to any one of claims 1 to 5, further comprising a floating substance collection pipe for collecting levitated material including inorganic silicon floating in the third tank in the vicinity of the liquid surface of the third tank. Separation system.

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