JP2013046465A - Rare earth magnet raw material recovery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To propose a rare earth magnet raw material recovery system which can recover rare earth magnet raw material powder from rotors having rare earth magnets as motor members used in a compressor, etc. safely and separately for each prescribed particle diameter.SOLUTION: The rare earth magnet raw material recovery system comprises: a crusher 5 which has a revolving shaft 3 and a wire rod 4 fixed at one end to the revolving shaft 3 installed in a cylindrical body into which a rotor 13 having been demagnetized is thrown, and also has a supply pipe 6a which supplies inert gas and a first exhaust pipe 7 connected thereto; a cyclone 8 which has the first exhaust pipe 7 connected thereto and also a recovery unit 8a for recovering rare earth magnet raw material powder larger in size than a prescribed particle diameter installed at the bottom, and which also has a second exhaust pipe 9 for discharging rare earth magnet raw material powder less than the prescribed particle diameter installed at the top; and a wet type dust collector 10, having the second exhaust pipe 9 connected thereto and also a suction fan 14 for sucking in via the first and the second exhaust pipes 7, 9 installed therein, which collects the rare earth magnet raw material powder less than the prescribed particle diameter to recover it.

Description

  The present invention relates to a rare earth magnet material recovery system for recovering a rare earth magnet material from a motor member used in a compressor or the like.

  In recent years, from the viewpoint of energy saving and ecology, next-generation eco-friendly vehicles such as hybrid vehicles and electric vehicles have been desired, and the automobile industry has been developing and selling next-generation eco-friendly vehicles one after another. The progress has been remarkable, and in particular, motors and batteries, which can be said to be the heart of hybrid cars and electric cars, have been reduced in size and performance, and further evolution is required in the future. Along with this, raw materials such as rare metals and rare earths are used in rare earth magnets used in motors, and their prices are on the rise, and there is a need for recycling from the viewpoint of resource protection.

  By the way, the rare earth magnet containing the rare earth (rare earth element) is used not only for motors of next-generation environment-friendly vehicles such as hybrid vehicles, but also for OA equipment and home appliances using advanced technology. Particularly in home appliances, rare earth magnets are used in relatively new types of air conditioners, refrigerator compressors, and washing machine motors manufactured after 2000.

  In addition, considering that the usage period of home appliances is approximately 10 years, it is speculated that home appliances using rare earth magnets, especially air conditioners and washing machines, have already been recovered in existing home appliance recycling routes. . Therefore, it is considered possible to recover recycled resources such as rare metals and rare earths by collecting home appliances such as air conditioners and washing machines using rare earth magnets from this home appliance recycling route.

  Therefore, in the process of collecting and recycling used home appliances, disassemble the motor member of the compressor of the air conditioner or refrigerator, or the washing machine, and collect the rare earth magnet as a plate from the rotor having the rare earth magnet. Although the method has been studied, there are problems such as taking time and labor, so it has not been commercialized.

  Further, as a rare earth recovery method, there is a recycling method in which a rare earth magnet is dissolved in an acid to extract a rare earth element. This method requires crushing of the rare earth magnet as a pretreatment. As a pretreatment for crushing the rare earth magnet, for example, in the following Patent Document 1, a rotor separated from a motor member used for a compressor or the like is demagnetized, and the demagnetized rotor is put into a crusher to crush. Then, a method of separating the crushed crushed material into a powder containing ferrous and non-ferrous metals and a rare earth magnet material using a sieving machine or the like has been proposed.

  However, in the conventional crushing method, since the rotor is crushed by the crusher and the crushed material is separated by a sieving machine, the rare earth magnet material obtained by crushing and sorting is performed in an air atmosphere. There is a problem that the powder of this product is easily oxidized and has a high risk of ignition. In particular, since the powder of rare earth magnet material is ignited at about several hundred μm, when the rotor is crushed by the crusher and when the crushed material is separated by the sieving machine, the crusher There is also a problem that the above-mentioned crushed material crushed in is extremely high in danger of igniting.

  In addition, when the pulverized material obtained by crushing in the crusher is transported to the next step in which the rare earth magnet raw material powder separated and separated by the sieving machine is dissolved in the acid, which is the rare earth recovery method, The rare earth magnet powder must be soaked and sludged to reduce the risk of ignition, resulting in increased costs and labor due to additional equipment and increased personnel for transportation and storage. There is also.

JP 2001-110636 A

  The present invention has been made in view of such circumstances, and safely and rarely collects rare earth magnet material powder for each predetermined particle size from a rotor having a rare earth magnet of a motor member used in a compressor or the like. It is an object of the present invention to propose a rare earth magnet material recovery system that can be used.

  In order to solve the above problems, the invention according to claim 1 is a rare earth magnet material recovery system for recovering a rare earth magnet material from a motor member in which a rotor having a rare earth magnet is incorporated, wherein the rare earth magnet material recovery system is separated from the motor member. In the cylinder into which the rotor that has been demagnetized is placed, a rotating shaft that is rotationally driven and a flexible wire that is fixed at one end to the rotating shaft and crushes the rotor, and an inert gas are provided. A crusher to which a supply pipe is connected and a first exhaust pipe is connected to the gas exhaust side, and the first exhaust pipe is connected to the gas introduction side and has a predetermined particle size or more at the bottom. A collection unit for collecting the rare earth magnet material powder is provided, and a second exhaust pipe for discharging the rare earth magnet material powder having a particle diameter of less than a predetermined particle size together with the inert gas is connected to the top. Ron and the second exhaust pipe are connected to the gas introduction side, a suction fan for sucking the inert gas through the first and second exhaust pipes is provided on the gas exhaust side, and And a wet dust collector that collects and collects the powder of the rare earth magnet material having a particle diameter of less than a predetermined particle accompanying the active gas.

  The invention according to claim 2 is the invention according to claim 1, wherein the cyclone has a particle size of 1 to 2 mm in which the powder of the rare earth magnet material having a predetermined particle size or more is separated by centrifugation. In addition, the rare earth magnet material powder having a particle size of less than a predetermined particle size has a particle size of less than 1 mm.

  According to this invention of Claim 1-2, the crusher which crushes the rotor which carried out the demagnetization process, the cyclone which isolate | separates the powder of a rare earth magnet raw material, and the powder of the said rare earth magnet raw material of less than predetermined particle diameter The wet dust collector that collects the body is connected by the first and second exhaust pipes, and the inert gas supplied by the supply pipe connected to the crusher is sucked in the wet dust collector. Since the air is sucked through the first and second exhaust pipes by the fan, the inside of the crusher, the cyclone and the wet dust collector can be made an inert gas atmosphere, and the cooling effect is increased and the powdery state is increased. The risk of ignition of the rare earth magnet material can be reduced. Thereby, it is possible to safely handle the rare earth magnet material powder that is easily oxidized and has a high risk of ignition.

  In addition, the rare earth magnet material is powdered by the impact of a flexible wire rod that is rotated by rotating the rotating shaft that is rotated at one end by inserting the rotor into the cylinder of the crusher. The rare earth magnet material powder is discharged from the crusher along with the inert gas via the first exhaust pipe connected to the gas exhaust side of the cylinder. Therefore, the powder of the rare earth magnet material can be quickly and easily taken out from the crushed material crushed by the crusher.

  Then, the cyclone separates the rare earth magnet material powder entrained in the inert gas from the first exhaust pipe connected to the gas introduction side by the cyclone, and has a predetermined particle size or more, for example, about 1 to 2 mm. The rare earth magnet material powder is recovered from a recovery portion provided at the bottom, and the rare earth magnet material powder having a particle size of less than a predetermined particle size, for example, less than 1 mm, is connected to the upper portion. Since the exhaust pipe is accompanied and discharged by the inert gas, the inert gas sucked by the suction fan can easily separate the rare earth magnet material powder and has a predetermined particle size or more. Only the powder of the rare earth magnet material can be recovered. Thereby, the next process which changes with the particle size of the powder of the said rare earth magnet raw material can be performed efficiently.

  In addition, the wet type dust collector collects the rare earth magnet material powder having a specific particle size less than the specific particle size, which is easy to oxidize and has the highest risk of ignition. Therefore, the rare earth magnet material powder is recovered in a sludge state. can do. As a result, the collected powder of the rare earth magnet material can be safely and promptly transported to the next process, and the cost of equipment and personnel can be reduced.

It is process drawing which simulated the series of processes of the rare earth magnet raw material collection | recovery system of this invention.

  As shown in FIG. 1, one embodiment of the rare earth magnet material recovery system 1 of the present invention is a rotary shaft that is rotationally driven to a cylindrical body 2 into which a rotor 13 separated from a motor member and demagnetized is inserted. 3 and one end of which is fixed to the rotating shaft 3 to provide a flexible wire 4 for crushing the rotor 13, a supply pipe 6a for nitrogen gas (inert gas) is connected, and a gas exhaust side is A crusher 5 to which one exhaust pipe 7 is connected, a first exhaust pipe 7 connected to the gas introduction side, and a recovery unit 8a for recovering the rare earth magnet material powder having a predetermined particle size or more at the bottom. A cyclone 8 provided on the upper side and connected to a second exhaust pipe 9 for exhausting the rare earth magnet material powder having a particle size less than a predetermined particle size with the nitrogen gas; and the second exhaust pipe 9 is provided on the gas introduction side. Connected to the gas exhaust side A suction fan 14 for sucking the nitrogen gas through the first and second exhaust pipes 7 and 9 is provided, and the rare earth magnet material powder less than a predetermined particle size accompanied by the nitrogen gas is collected. A wet dust collector 10 to be recovered is provided and schematically configured.

  Here, the crusher 5 is a chain crusher 5. The chain crusher 5 is provided in a cylindrical body 2 with a bottom, and is provided with a columnar rotating shaft 3 that is erected at the center of the bottom of the cylindrical body 2 and is rotated by driving of a motor 11. One end is connected to the outer peripheral surface of the rotating shaft 3 and the other end is a free end, and the other end is connected to a position separated by 180 ° C. in the circumferential direction of the rotating shaft 3. It has a chain (wire) 4 whose end is a free end. Further, at least two chains 4 are connected to one side of the outer peripheral surface of the rotating shaft 3.

  The cylinder 2 is connected to the nitrogen gas generator 6 through a supply pipe 6a. By this nitrogen gas generator 6, nitrogen gas is supplied into the cylinder 2, and the inside of the cylinder 2 is maintained in a nitrogen gas atmosphere. And while the one side of the 1st exhaust pipe 7 is connected to the gas exhaust side of the cylinder 2, the opening-and-closing type which collects the iron and nonferrous metal in the crushed material which fractured the rotor 13 in the lower part of the cylinder 2 The chute 15 is connected.

  The cyclone 8 has the other side of the first exhaust pipe 7 connected to the gas introduction side, and discharges and collects the powder of the rare earth magnet material having a predetermined particle size or more, for example, about 1 to 2 mm, at the bottom. A collecting portion 8a is formed. Further, one side of a second exhaust pipe 9 that discharges the rare earth magnet material powder having a particle size of less than a predetermined particle size, for example, less than 1 mm, accompanied with the nitrogen gas is connected to the gas exhaust side at the top of the cyclone 8. ing.

  Further, the wet dust collector 10 is connected to the gas introduction side on the other side of the second exhaust pipe 9 and is provided with a suction fan 14 on the gas exhaust side and exhausts the nitrogen gas to the atmosphere on the gas exhaust side. A tube 12 is connected. Moreover, the wet dust collector 10 can use, for example, an electrostatic dust collection type wet electrostatic dust collector. This wet electrostatic precipitator forms a water film by allowing water to flow on the surface of the dust collecting electrode, and a method of collecting a mist (dust mist) in the water film and washing it with the water film, or a mist. There is a method of collecting the above-mentioned fumes of droplets and causing the surface of the dust collecting electrode to flow down. Furthermore, it is also possible to use a wet scrubber that efficiently collects dust by gas-liquid mixing a gas containing dust. Since this wet scrubber has a simple structure, it can be easily maintained.

  In order to recover the rare earth magnet material powder using the rare earth magnet material recovery system 1 configured as described above, first, the rotor 13 is separated from the motor member of the compressor by a machine and a manual operation. Then, as a pretreatment, the rotor 13 is demagnetized. This demagnetization process can be performed even at room temperature demagnetization (electrical demagnetization). However, if resin powder is mixed into the rare-earth magnet material powder that is the final recovered material, Since treatment is required, it is preferable to remove the resin by thermal demagnetization.

  When performing the above thermal demagnetization, the rotor 13 is put into a heating furnace, and the temperature is raised above the Curie temperature of the rare earth magnet contained in the rotor 13 and held for a certain time. At this time, when the rare earth magnet is a neodymium magnet, the Curie temperature of the neodymium magnet is 330 to 380 ° C., so the rotor 13 is heated at a temperature of 380 ° C. or higher by the heating furnace for about 15 minutes. Hold. As a result, the rare earth magnet contained in the rotor 13 is completely demagnetized.

  Then, after 15 minutes, the rotor 13 is taken out of the heating furnace and transferred to the cooling chamber. In this cooling chamber, for example, air is injected into the rotor 13 to cool it to a temperature at which handling is not hindered. At this time, considering that the incineration residue remains, the air in the cooling chamber is sucked by the suction means through the suction pipe connected to the cooling chamber, and the residue and dust are removed by the bag filter. Later, it is discharged to the atmosphere via a discharge pipe.

  Next, the rotor 13 that has been demagnetized is put into the cylinder 2 of the chain crusher 5 and crushed. At this time, the inside of the cylinder 2 is maintained in a nitrogen gas atmosphere by being supplied with nitrogen gas from the nitrogen gas generator 6 through the supply pipe 6a.

  In the cylinder 2, the rotor 13, one of which is connected to the rotating shaft 3 and the other of which is crushed by the impact of the flexible chain 4 having a free end, is greatly deformed by iron and non-ferrous metal. Instead, it is cut into a middle piece (a block of 3 mm square or more), and only the rare earth magnet material is selectively crushed into powder. This is due to the difference in the elastoplasticity of each material, and the crushing shape varies depending on the material due to the impact of the impact of the flexible chain 4. Then, the iron and non-ferrous metal are discharged and collected from an openable chute 15 provided below the cylinder 2.

  Also, the rare earth magnet material powder is entrained by the nitrogen gas sucked by the suction fan 14 provided in the wet dust collector 10, and from the first exhaust pipe 7 connected to the gas exhaust side of the cylindrical body 2. Discharged. The discharged rare earth magnet material powder is collected in a cyclone 8 to which the other side of the first exhaust pipe 7 is connected.

  The powder of the rare earth magnet material is centrifuged in the cyclone 8 by the flow rate of the nitrogen gas sucked by the suction fan 14, and the rare earth magnet material having a specific particle size or more, for example, about 1 to 2 mm. The rare earth magnet material powder having a specific particle size or larger is provided at the bottom of the cyclone 8. It is discharged from the collecting unit 8a and collected. The rare earth magnet material powder having a specific particle size or larger discharged and collected from the collection unit 8a of the cyclone 8 is difficult to be acid-dissolved at this particle size, so that it is pulverized by a machine such as a mill as the next step. There is a need to.

  Further, from the second exhaust pipe 9 connected to the gas exhaust side at the upper part of the cyclone 8, the rare earth magnet material powder having a particle diameter less than a specific particle size is discharged along with the nitrogen gas sucked by the suction fan 14. Is done. Then, the discharged rare earth magnet material powder having a particle diameter less than the predetermined particle diameter is collected and collected by the wet dust collector 10 to which the other side of the second exhaust pipe 9 is connected. At this time, the rare earth magnet material powder having a particle diameter less than the specific particle size entrained by the nitrogen gas is collected by a wet dust collector 10 such as a wet scrubber and collected in a sludge state.

  Further, the nitrogen gas is released to the atmosphere from an exhaust pipe 12 provided on the gas exhaust side of the wet dust collector 10. And since the rare earth magnet raw material powder having a particle diameter less than the specific particle size collected and collected by the wet dust collector 10 is in a sludge state, it is directly conveyed to the next step in which the acid dissolution treatment is performed.

  According to the rare earth magnet material recovery system 1 according to the above-described embodiment, the chain crusher 5 that crushes the rotor 13 that has been demagnetized, the cyclone 8 that centrifuges the rare earth magnet material powder, and the predetermined particle size. A wet dust collector 10 that collects less than the rare earth magnet material powder is connected by the first and second exhaust pipes 7 and 9 and supplied by the supply pipe 6 a connected to the chain crusher 5. Since the nitrogen gas (inert gas) is sucked through the first and second exhaust pipes 7 and 9 by the suction fan 14 provided in the wet dust collector 10, the chain crusher 5 and the cyclone 8 and The inside of the wet dust collector 10 can be made into a nitrogen gas atmosphere, the cooling effect can be increased, and the risk of ignition of the powdery rare earth magnet material can be reduced. Thereby, it is possible to safely handle the rare earth magnet material powder that is easily oxidized and has a high risk of ignition.

  Further, the rotor 13 is inserted into the cylindrical body 2 of the chain crusher 5, and the rare earth is caused by the impact of the flexible chain 4 having one end fixed to the rotating shaft 3 that rotates and rotating. While the magnet material is crushed into powder, the rare earth magnet material powder is accompanied by the inert gas via the first exhaust pipe 7 connected to the gas exhaust side of the cylindrical body 2, Since it is discharged from the chain crusher 5, the powder of the rare earth magnet material can be quickly and easily taken out from the crushed material crushed by the chain crusher 5.

  The cyclone 8 separates the rare earth magnet material powder entrained in the nitrogen gas from the first exhaust pipe 7 connected to the gas introduction side, and has a predetermined particle size or more, for example, about 1 to 2 mm. The rare earth magnet material powder is recovered from the recovery portion 8a provided at the bottom, and the rare earth magnet material powder having a particle size of less than a predetermined particle size, for example, less than 1 mm, is connected to the upper portion of the second exhaust. Since the tube 9 discharges the nitrogen gas along with the nitrogen gas, the nitrogen gas sucked by the suction fan 14 can easily separate the rare earth magnet material powder, and the rare earth having a predetermined particle size or more. Only the magnetic material powder can be collected. Thereby, the next process which changes with the particle size of the powder of the said rare earth magnet raw material can be performed efficiently.

  In addition, the wet dust collector 10 collects the rare earth magnet material powder having a specific particle size less than the specific particle size, which is easy to oxidize and has the highest risk of ignition. Therefore, the rare earth magnet material powder is recovered in a sludge state. can do. As a result, the collected powder of the rare earth magnet material can be safely and promptly transported to the next process, and the cost of equipment and personnel can be reduced.

In the above embodiment, the crusher 5 is described using only the chain crusher 5, one end of which is connected to the rotary shaft 3 and the other end is a free end chain 4. The present invention is not limited to this, and it is also possible to use a flexible wire instead of the chain 4.
Moreover, in the said embodiment, although the rare earth magnet included in the rotor 1 demonstrated only when it was a neodymium magnet, it is not limited to this, For example, even when a samarium cobalt magnet is used, it can respond. is there. In that case, since the Curie temperature of the samarium cobalt magnet is 750 to 800 ° C., the heating temperature of the heating furnace is 800 ° C.

  It can be used for a rotor separated from a motor member used for a compressor or the like.

1 rare earth magnet material recovery system 2 cylinder 3 rotating shaft 4 chain (wire)
5 Chain crusher (crusher)
6 Nitrogen Gas Generator 7 First Exhaust Pipe 8 Cyclone 8a Recovery Unit 9 Second Exhaust Pipe 10 Wet Dust Collector 11 Motor 12 Exhaust Pipe 13 Rotor 14 Suction Fan 15 Chute

Claims (2)

A rare earth magnet material recovery system for recovering a rare earth magnet material from a motor member incorporating a rotor having a rare earth magnet,
A rotating shaft that is driven to rotate and a flexible wire that has one end fixed to the rotating shaft and crushes the rotor in a cylinder into which the rotor separated from the motor member and demagnetized is inserted. A crusher having a supply pipe for supplying an inert gas connected thereto and having a first exhaust pipe connected to the gas exhaust side;
The first exhaust pipe is connected to the gas introduction side, a recovery unit for recovering the rare earth magnet material powder having a predetermined particle diameter or more is provided at the bottom, and the rare earth magnet having a particle diameter less than the predetermined particle is provided at the top A cyclone connected to a second exhaust pipe for exhausting the powder of the material together with the inert gas;
The second exhaust pipe is connected to the gas introduction side, a suction fan for sucking the inert gas through the first and second exhaust pipes is provided on the gas exhaust side, and the inert gas A rare earth magnet material recovery system comprising: a wet dust collector that collects and recovers the powder of the rare earth magnet material having a particle size less than the accompanying particle size.   In the cyclone, the rare earth magnet material powder having a particle diameter of not less than a predetermined particle diameter is 1 to 2 mm, and the rare earth magnet material powder having a particle diameter of less than a predetermined particle diameter is less than 1 mm. The said rare earth magnet raw material collection | recovery system of Claim 1 characterized by the above-mentioned.

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