Carbon nanotube recovery device and carbon nanotube manufacturing device

Abstract

This carbon nanotube recovery device comprises: a winding chamber; a recovery chamber; a partition door; a door chamber in which the partition door is stored; a shielding member provided between the winding chamber and the door chamber; a first cleaning part made of an elastic body and provided slidably with respect to a ceiling surface in the door chamber; and a second cleaning part made of an elastic body and provided slidably with respect to a bottom surface in the door chamber.

Description

Carbon nanotube recovery device and carbon nanotube production apparatus

[0001] The present invention relates to a carbon nanotube recovery device for recovering carbon nanotubes and a carbon nanotube production apparatus including the carbon nanotube recovery device.

[0002] Carbon nanotubes (hereinafter sometimes referred to as "CNT") are a material having excellent properties such as electrical conductivity, thermal conductivity, and mechanical strength. As an apparatus for producing such CNTs, Patent Document 1 and Patent Document 2 disclose an apparatus that winds up CNTs generated in a reaction tube to form a massive wound body, temporarily stores the CNT wound body in a recovery chamber, and periodically recovers the CNT wound body.

[0003] In the above apparatus, an openable / closable gate valve is provided between a winding chamber for winding CNTs and a recovery chamber for recovering CNTs, and the gate valve can block the atmosphere in the winding chamber from the atmosphere in the recovery chamber. When recovering the CNT wound body stored in the recovery chamber, by appropriately controlling the atmosphere in the recovery chamber with the gate valve closed, CNTs can be recovered while continuing the production of CNTs.

[0004] Japanese Patent Application Publication No. 2024-055670 Japanese Patent Application Publication No. 2024-058963

[0005] In the apparatuses described in Patent Document 1 and Patent Document 2, CNTs generated in the reaction tube are discharged from the lower end of the reaction tube and wound up by contacting a winding roller in the winding chamber, but some CNTs do not contact the winding roller and float in the winding chamber. CNT production is performed with the gate valve open except for the step of recovering the CNT wound body, so CNTs floating in the winding chamber (hereinafter sometimes referred to as "floating CNTs") move from the winding chamber to the recovery chamber together with the carrier gas.

[0006] Floating CNTs that have moved into the recovery chamber may adhere to the surface of the valve plate constituting the gate valve and the wall surface of the recovery chamber. These floating CNTs may also adhere to the surface of the sealing material provided on the gate valve or to the ceiling surface of the recovery chamber that the sealing material contacts. If the gate valve is closed in this state, floating CNTs will get trapped in the sealing surface, resulting in a seal failure. In this state of a seal failure, even if the gate valve is closed, the atmosphere in the winding chamber will flow into the recovery chamber, making it impossible to control the atmosphere in the recovery chamber to one suitable for recovering the CNT windings. In such cases, the CNT windings cannot be recovered from the recovery chamber, requiring the cessation of CNT production and the cooling and shutdown of the equipment, which reduces productivity.

[0007] The present invention has been made in view of the above circumstances, and aims to suppress the decrease in sealing performance caused by the adhesion of CNTs to the sealing surface in a carbon nanotube recovery device that can isolate the atmosphere between the winding chamber and the recovery chamber.

[0008] The present invention, which solves the above problems, is a carbon nanotube recovery apparatus for recovering generated carbon nanotubes, comprising: a winding chamber on which the carbon nanotubes are wound; a recovery chamber provided below the winding chamber for recovering the carbon nanotubes; a partition door that separates the atmosphere inside the winding chamber from the atmosphere inside the recovery chamber; a door chamber in which the partition door is stored, having a first opening leading to the winding chamber and a second opening leading to the recovery chamber; a shielding member provided between the winding chamber and the door chamber that can open and close the first opening; a moving mechanism for moving the partition door between a retracted position that does not close the first and second openings and a closed position that does close them; a first cleaning unit made of an elastic body that is slidably provided with respect to the ceiling surface inside the door chamber around the first opening; and a second cleaning unit made of an elastic body that is slidably provided with respect to the bottom surface inside the door chamber around the second opening.

[0009] From another perspective, the present invention is a carbon nanotube manufacturing apparatus for generating and recovering carbon nanotubes, characterized in that it comprises a generating apparatus for generating carbon nanotubes and the carbon nanotube recovery apparatus described above.

[0010] According to the present invention, in a carbon nanotube recovery apparatus capable of separating the atmosphere between the winding chamber and the recovery chamber, it is possible to suppress the decrease in sealing performance caused by the adhesion of CNTs to the sealing surface.

[0011] This figure shows a schematic configuration of a carbon nanotube manufacturing apparatus according to an embodiment of the present invention. This figure shows a schematic configuration of a partition door according to an embodiment of the present invention. This figure illustrates an example of the configuration of a cleaning unit for removing CNTs attached to the ceiling surface inside the door compartment. This figure illustrates another example of the configuration of the cleaning unit. This figure illustrates another example of the configuration of the cleaning unit. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus. This figure illustrates the operation of the carbon nanotube manufacturing apparatus.

[0012] Embodiments of the present invention will be described below with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant explanations will be omitted.

[0013] <Carbon Nanotube Manufacturing Apparatus> Figure 1 shows a schematic configuration of a carbon nanotube (CNT) manufacturing apparatus according to this embodiment. The CNTs in this embodiment are tubular carbon allotropes (typically cylindrical structures with a graphite structure), and include so-called single-walled CNTs, multi-walled CNTs, or carbon nanohorns with angular tube ends. The CNT manufacturing apparatus 1 is particularly suitable for the production of single-walled CNTs.

[0014] The CNT manufacturing apparatus 1 comprises a generating apparatus 10 for generating CNTs and a recovery apparatus 20 for recovering the CNTs. In Figure 1, the "X direction" is the depth direction of the recovery apparatus 20, the "Y direction" is the width direction of the recovery apparatus 20, and the "Z direction" is the vertical direction. These X, Y, and Z directions are perpendicular to each other.

[0015] (Carbon Nanotube Production Apparatus) The CNT production apparatus 10 is an apparatus that produces carbon nanotubes (CNTs) using chemical vapor deposition (CVD), and produces CNTs by thermally decomposing raw materials such as catalyst metals or catalyst metal compounds. When the raw materials for CNTs are supplied to the production apparatus 10, a carrier gas (for example, hydrogen gas) is also supplied along with the raw materials.

[0016] The generating apparatus 10 includes a reaction tube 11 to which the raw materials for CNTs are supplied, and a heater 12 arranged around the reaction tube 11.

[0017] The reaction tube 11 is a straight tubular body, but its shape is not particularly limited. The cross-sectional shape of the reaction tube 11 perpendicular to the tube axis may be a rounded shape such as a circle, ellipse, or egg shape, or a polygonal shape. The material of the reaction tube 11 is selected considering factors such as heat resistance to the CNT formation temperature, thermal shock resistance, weather resistance and corrosion resistance to the atmospheric gas during CNT formation. For example, alumina (Al2O3), mullite, silicon carbide (SiC), quartz glass, Kanthal (iron-chromium-aluminum alloy), Inconel, and carbon can be used as materials for the reaction tube 11.

[0018] A raw material supply port (not shown) for supplying CNT raw materials and carrier gas is formed at the upper end of the reaction tube 11. CNTs are produced as the raw materials supplied from the raw material supply port pass through the reaction tube 11, which is heated by the heater 12. The produced CNTs are discharged from the lower end of the reaction tube 11.

[0019] The shape and heating method of the heater 12 are not particularly limited as long as they can heat the reaction tube 11 to a temperature suitable for CNT production. For example, a tungsten heater capable of heating the reaction tube 11 to 500°C to 2000°C, or a carbon heater or silicon carbide heater (SiC heater) capable of heating to 600°C to 1600°C, can be used as the heater 12.

[0020] Although the tube axis direction of the reaction tube 11 was vertical in this example, the tube axis direction may be horizontal or in any other direction.

[0021] (Carbon nanotube recovery device) The recovery device 20 is located below the generation device 10. The recovery device 20 has a winding chamber 30 for winding up CNTs, a recovery chamber 40 for recovering the CNT winding body R, and a door chamber 50 located between the winding chamber 30 and the recovery chamber 40.

[0022] The winding chamber 30 has a winding space 31 where the CNTs are wound up, and a temporary storage space 32 for the CNTs located below the winding space 31.

[0023] A winding roller 33 for winding CNTs is installed in the winding space 31. The winding roller 33 is capable of moving forward and backward in the horizontal direction (in this embodiment, the X direction) by a reciprocating movement mechanism such as a cylinder mechanism, and is also configured to be rotatable with the X direction as its axis of rotation by a rotational drive source such as a motor. When winding CNTs, the winding roller 33 rotates with the winding roller 33 in the forward position in the negative X direction, and the CNTs discharged from the lower end of the reaction tube 11 are wound up by the winding roller 33. The resulting CNT winding body R falls from the tip of the winding roller 33 toward the temporary storage space 32 as the winding roller 33 retracts toward the positive X direction.

[0024] The temporary storage space 32 is a space for temporarily storing the CNT winding body R without dropping it into the recovery chamber 40 during the CNT recovery process described later. Therefore, when the CNT is not being recovered, the CNT winding body R formed in the winding space 31 passes through the temporary storage space 32 and falls into the recovery chamber 40.

[0025] A retractable recovery door 43 is attached to the side wall of the recovery chamber 40. During the CNT recovery process, the recovery door 43 is opened, and the CNT winding R inside the recovery chamber 40 is recovered.

[0026] (Partition Door) Figure 2 is an enlarged view of the door room 50. The door room 50 is sealed from the atmosphere and has a first opening 51 leading to the winding room 30 and a second opening 52 leading to the recovery room 40. Inside the door room 50 is a partition door 60 that separates the atmosphere inside the winding room 30 from the atmosphere inside the recovery room 40.

[0027] The partition door 60 is configured to be movable between a retracted position P1 in which it does not close the first opening 51 and the second opening 52, and a closed position P2 in which it closes the first opening 51 and the second opening 52. The moving mechanism 61 for moving the partition door 60 is, for example, a reciprocating mechanism such as a cylinder mechanism, which moves the partition door 60 along the horizontal direction (the X direction in this embodiment).

[0028] The partition door 60 has a first plate 62 for closing the first opening 51, a second plate 63 for closing the second opening 52, and a third plate 64 positioned between the first plate 62 and the second plate 63.

[0029] Each of the plates 62 to 64 is a rectangular plate and is arranged in a direction parallel to the horizontal plane. The first plate 62 is positioned opposite the ceiling surface inside the door room 50, and the outer dimensions of the first plate 62 in a top view are larger than the outer dimensions of the first opening 51. The second plate 63 is positioned opposite the bottom surface inside the door room 50, and the outer dimensions of the second plate 63 in a top view are larger than the outer dimensions of the second opening 52. In addition, in the retracted position P1, there is a gap between the first plate 62 and the ceiling surface inside the door room 50, and there is a gap between the second plate 63 and the bottom surface inside the door room 50.

[0030] The first plate 62 and the third plate 64 are connected to each other by a plurality of links 65, and each link 65 is spaced apart in the forward and backward direction of the partition door 60 (in this embodiment, the X direction). The upper end of each link 65 is attached to the side of the first plate 62, and the lower end of each link 65 is attached to the side of the third plate 64. In addition, in the retracted position P1 of the partition door 60, the upper end of each link 65 is on the closed position P2 side than the lower end, and each link 65 is inclined with respect to the vertical direction.

[0031] The second plate 63 and the third plate 64 are connected to each other by a plurality of links 66, each link 66 being spaced apart in the forward and backward direction of the partition door 60. The upper end of each link 66 is attached to the side of the third plate 64, and the lower end of each link 66 is attached to the side of the second plate 63. In addition, in the retracted position P1 of the partition door 60, the lower end of each link 66 is closer to the closed position P2 than the upper end, and each link 66 is inclined with respect to the vertical direction.

[0032] The rear end (the end on the positive side in the X direction) of the third plate 64 in the direction of movement of the partition door 60 is connected, for example, to the cylinder rod of the moving mechanism 61, and the third plate 64 is configured to be able to move forward or backward by the moving mechanism 61. When the third plate 64 is pushed from the retracted position P1 to the closed position P2, the front ends of the first plate 62 and the second plate 63 come into contact with a stopper (not shown), causing the inclined links 65 and 66 to face vertically. As a result, the first plate 62 rises from its initial position and the second plate 63 descends from its initial position.

[0033] A first sealing material 67, such as an O-ring, is provided on the upper surface of the partition door 60 (the upper surface of the first plate 62 in this embodiment), and a second sealing material 68, such as an O-ring, is provided on the lower surface of the partition door 60 (the lower surface of the second plate 63 in this embodiment). The material of each sealing material 67, 68 is not particularly limited as long as it is a material that can provide gas sealing, but considering the heat resistance and durability against high-temperature carrier gases, fluororubber is preferred.

[0034] When the first plate 62 rises, the first sealing material 67 comes into contact with the ceiling surface inside the door chamber 50, closing the first opening 51, thereby separating the atmosphere inside the winding chamber 30 from the atmosphere inside the door chamber 50. When the second plate 63 descends, its second sealing material 68 comes into contact with the bottom surface inside the door chamber 50, closing the second opening 52, thereby separating the atmosphere inside the recovery chamber 40 from the atmosphere inside the door chamber 50.

[0035] As described above, the partition door 60 according to this embodiment is movable between the retracted position P1 and the closed position P2, and has a structure that can extend and retract vertically in the closed position P2, thereby separating the atmosphere inside the winding chamber 30 from the atmosphere inside the recovery chamber 40. Note that the configuration of the partition door 60 is not limited to the configuration described in this embodiment.

[0036] (CNT Cleaning Section) Floating CNTs that have moved from the winding chamber 30 along with the carrier gas adhere to the ceiling surface of the door chamber 50 surrounding the first opening 51 and the bottom surface of the door chamber 50 surrounding the second opening 52. A first cleaning section 70 is attached to the front end (negative end in the X direction) of the first plate 62 as a CNT cleaning section to remove CNTs that have adhered to the ceiling surface of the door chamber 50. A second cleaning section 71 is attached to the front end (negative end in the X direction) of the second plate 63 as a CNT cleaning section to remove CNTs that have adhered to the bottom surface of the door chamber 50.

[0037] Each cleaning section 70, 71 is preferably an elastic body that deforms elastically with a small external force and is made of a material that does not damage the sealing surface through sliding with it. The material of each cleaning section 70, 71 is, for example, a thermosetting elastomer, and among thermosetting elastomers, synthetic rubber is preferred. Considering heat resistance and durability against high-temperature carrier gases, the material of each cleaning section 70, 71 is even more preferably fluororubber.

[0038] Each cleaning section 70 and 71 illustrated in Figure 2 is a thin, rectangular flat plate. The width (length in the Y direction) of the first cleaning section 70 is longer than the total width of the first sealing material 67 surrounding the first opening 51. For example, if the first sealing material 67 is an annular shape such as an O-ring, the width of the first cleaning section 70 is longer than the outer diameter of the first sealing material 67. Similarly, the width (length in the Y direction) of the second cleaning section 71 is longer than the width of the second sealing material 68 surrounding the second opening 52. Note that the above-mentioned length in the Y direction can be rephrased as the length in the horizontal direction perpendicular to the direction of movement of the partition door 60.

[0039] When the partition door 60 is in the retracted position P1, the upper end of the first cleaning unit 70 is in contact with the ceiling surface inside the door room 50, and the lower end of the second cleaning unit 71 is in contact with the bottom surface inside the door room 50. When the partition door 60 is moved from the retracted position P1 to the closed position P2, the first cleaning unit 70 slides against the ceiling surface inside the door room 50, and the second cleaning unit 71 slides against the bottom surface inside the door room 50. As a result, while the partition door 60 moves from the retracted position P1 to the closed position P2, the respective cleaning units 70 and 71 can peel off and remove the CNTs adhering to the ceiling and bottom surfaces inside the door room 50.

[0040] Furthermore, in the closed position P2, when the first plate 62 rises and the second plate 63 descends as described above, the cleaning sections 70 and 71 bend, so the sealing function of the sealing materials 67 and 68 is not obstructed. In order to accommodate the bent cleaning sections 70 and 71, a notch 62a is formed at the front end of the first plate 62 and a notch 63a is formed at the front end of the second plate 63.

[0041] The mounting positions of the first cleaning unit 70 and the second cleaning unit 71 on the partition door 60 are not limited to the positions illustrated in Figure 2, but can be appropriately changed depending on the structure of the partition door 60 and the shape of the cleaning units 70 and 71. However, if the cleaning units 70 and 71 are configured to slide against the ceiling and bottom surfaces of the door room 50 in conjunction with the forward movement of the partition door 60, as in this embodiment, it is preferable that the first cleaning unit 70 is positioned on the first opening 51 side of the first sealing material 67 in the retracted position P1, and the second cleaning unit 71 is positioned on the second opening 52 side of the second sealing material 68 in the retracted position P1.

[0042] Further, when the partition door 60 is at the retracted position P1 as in the present embodiment, the first cleaning part 70 is in contact with the ceiling surface in the door chamber 50 and the second cleaning part 71 is in contact with the bottom surface in the door chamber 50, the presence of the respective cleaning parts 70 and 71 can suppress the inflow of floating CNT into the door pocket space.

[0043] The first cleaning part 70 and the second cleaning part 71 described above may be configured as shown in Figs. 3 to 5, for example. Although the second cleaning part 71 is not illustrated in Figs. 3 to 5, the configuration of the second cleaning part 71 and its surroundings is the same as that obtained by vertically inverting the configuration of the first cleaning part 70 and its surroundings shown in Figs. 3 to 5.

[0044] The first cleaning part 70 illustrated in Fig. 3 has a flat plate shape similar to that in Fig. 2, but the lower end of the first cleaning part 70 is sandwiched and fixed between the first plate 62 and the fixing member 72. An auxiliary member 73 is fixed to the upper surface of the fixing member 72, and the surface of the auxiliary member 73 on the first cleaning part 70 side is an inclined surface. The upper end of the inclined surface is located closer to the first cleaning part 70 side than the lower end, and the upper end of the first cleaning part 70 in contact with such an inclined surface is always inclined toward the notch 62a side. Therefore, when the first plate 62 is raised, the first cleaning part 70 is easily bent, and the repulsive force received from the first cleaning part 70 when the first plate 62 is pressed against the ceiling surface in the door chamber 50 is reduced. This improves the sealing performance on the sealing surface.

[0045] The first cleaning part 70 illustrated in Fig. 4 has a shape that allows the functions obtained by the first cleaning part 70, the fixing member 72 and the auxiliary member 73 shown in Fig. 3 to be realized with a single component. The first cleaning part 70 in Fig. 4 has a base portion fitted into the first plate 62, and a protruding portion branched from the base portion and inclined toward the first sealing material 67 side, and is formed in a V-shape or Y-shape.

[0046] The first cleaning unit 70 illustrated in Fig. 5 is formed in a cylindrical shape, and can remove CNT adhering to the ceiling surface in the door chamber 50 by having a part of its outer peripheral surface slide against the ceiling surface. Further, when the first plate 62 is pressed into the door chamber 50, the first cleaning unit 70 is crushed and deformed, so the sealing performance at the sealing surface is ensured.

[0047] In any of the configurations illustrated above, the first cleaning unit 70 is an elastic body provided slidably relative to the ceiling surface in the door chamber 50 around the first opening 51, and the second cleaning unit 71 is an elastic body provided slidably relative to the bottom surface in the door chamber 50 around the second opening 52. It should be noted that each of the cleaning units 70 and 71 may be configured to move independently of the partition door 60, for example. Further, for example, the cleaning units 70 and 71 may be configured as a single component instead of separate components.

[0048] (Shielding Member) As shown in Fig. 1, a shutter 80 is installed between the winding chamber 30 and the door chamber 50 as an example of a shielding member that opens and closes the first opening 51. The outer shape of the shutter 80 in top view is larger than the outer shape of the first opening 51, and the shutter 80 is configured to be movable in the horizontal direction (the X direction in the present embodiment) by a reciprocating movement mechanism such as a cylinder mechanism (not shown).

[0049] With the shutter 80 configured as described above, it is possible to switch between a state where the first opening 51 of the door chamber 50 is covered by the shutter 80 (closed state) and a state where it is not covered (open state). Since this shutter 80 is intended to block the falling of the CNT wound body R when recovering CNT which will be described later, it is not essential for the shutter 80 to have a function of blocking the atmosphere in the winding chamber 30 from the atmosphere in the door chamber 50.

[0050] When the atmosphere in the winding chamber 30 and the atmosphere in the door chamber 50 are not blocked by the shutter 80, there is a gap between the bottom surface inside the housing in which the shutter 80 is stored and the lower surface of the shutter 80 even if the first opening 51 is closed by the shutter 80. For this reason, floating CNT moving together with the carrier gas from the winding chamber 30 may wrap around the peripheral edge of the shutter 80 and pass through the first opening 51.

[0051] Even in that case, since the first opening 51 is closed from the door room 50 side by the partition door 60 (Figure 2), floating CNTs will not flow into the door room 50. However, floating CNTs may adhere to the upper surface of the partition door 60 (the upper surface of the first plate 62 in this embodiment). Even if floating CNTs adhere to the upper surface of the partition door 60, the function of the partition door 60 will not be immediately impaired. However, when the closure of the first opening 51 by the partition door 60 is released, floating CNTs will enter the pocket space of the door room 50. If a large amount of floating CNTs enter the pocket space of the door room 50, the partition door 60 may malfunction.

[0052] Before such malfunctions occur in the partition door 60, CNTs that have entered the door pocket space of the door room 50 are removed by periodic maintenance work. However, from the viewpoint of improving productivity, it is desirable to reduce the frequency of maintenance. In this regard, it is preferable that the lower surface of the shutter 80 is close to or in contact with the bottom surface of the housing in which the shutter 80 is housed. This reduces the amount of floating CNTs that wrap around the periphery of the shutter 80 and head toward the first opening 51, and suppresses the adhesion of floating CNTs to the upper surface of the partition door 60.

[0053] (Gas supply and discharge mechanism) As shown in Figure 1, the winding chamber 30 has an exhaust port 34 for discharging the atmosphere inside the winding chamber 30. A valve 35 is attached to the piping connecting the exhaust port 34 to an exhaust pump (not shown).

[0054] The recovery chamber 40 has an inert gas supply port 44 for supplying an inert gas such as argon, an air supply port 45 for supplying air, and an exhaust port 46 for discharging the atmosphere inside the recovery chamber 40. A valve 47 is installed in the piping connecting the inert gas supply port 44 to a gas supply source (not shown). A pressure restoration valve 48 is installed in the piping connected to the air supply port 45. A valve 49 is installed in the piping connecting the exhaust port 46 to a vacuum pump (not shown).

[0055] The door room 50 has an inert gas supply port 53 through which an inert gas such as argon gas is supplied. A valve 54 is attached to the piping connecting the inert gas supply port 53 to a gas supply source (not shown).

[0056] The inert gas supply port 53 is preferably located in a region on the side of the retracted position P1 that is further back than the first opening 51 and the second opening 52 shown in Figure 2. By supplying inert gas to this region, floating CNTs passing through the first opening 51 and the second opening 52 together with the carrier gas are less likely to flow into the region on the retracted position P1 side, i.e., into the door pocket space. This suppresses the occurrence of malfunctions caused by the adhesion of CNTs to the drive components of the partition door 60. From the viewpoint of enhancing this effect, it is preferable that the inert gas supply port 53 is located in a region further back (on the opposite side from the openings 51 and 52) than the partition door 60 in the retracted position P1.

[0057] Furthermore, the door compartment 50 has an exhaust port 55 on the side wall opposite to the door pocket space side for discharging the atmosphere inside the door compartment 50. A valve 56 and a pressure gauge 57, which serves as a pressure measuring unit for measuring the pressure inside the door compartment 50, are attached to the piping connecting the exhaust port 55 and an exhaust pump (not shown). The pressure value information inside the door compartment 50 measured by the pressure gauge 57 is output to the control unit 100, which will be described later.

[0058] Furthermore, the piping connected to each of the exhaust ports 34, 55, and 46 described above is equipped with a filter (not shown), and any floating CNTs flowing into the piping are captured by the filter. Also, the configuration of the gas supply and discharge mechanism described above is just one example, and the specific configuration can be modified as appropriate to replace the atmosphere in each room with the desired atmosphere.

[0059] (Control Unit) The operation of the CNT manufacturing apparatus 1 is controlled by the control unit 100. The control unit 100 is a computer equipped with, for example, a CPU and memory, and has a program storage unit (not shown). The program storage unit stores various programs, including commands for controlling the generation and winding of CNTs in the CNT manufacturing apparatus 1 (described later), the operation of the shutter 80, the operation of the partition door 60, and the operation of each valve that adjusts the gas supply flow rate and discharge flow rate. Note that the above programs may have been recorded on a storage medium readable by the computer and installed from that storage medium to the control unit 100. Note that although the control unit 100 shown in Figure 1 is illustrated focusing only on its relationship with the pressure gauge 57, the control unit 100 can also control other components necessary for the operation of the CNT manufacturing apparatus 1.

[0060] The schematic configuration of the CNT manufacturing apparatus 1 according to this embodiment has been described above.

[0061] Furthermore, while steel is used as the material for components such as the door chamber 50, partition door 60, and shutter 80, stainless steel is preferable considering heat resistance to carrier gas temperature and the impact of rust on CNT quality. In addition, it is preferable to apply a fluororesin coating to the surfaces of components that come into contact with CNTs in the CNT manufacturing apparatus 1. Examples of coating materials include polytetrafluoroethylene (PTFE), perfluoroalkoxyalkane (PFA), and polybenzimidazole (PBI). Moreover, it is preferable to apply a heat-resistant coating to the surfaces of components exposed to high temperatures in the CNT manufacturing apparatus 1. Examples of coating materials include titanium aluminum nitride (TiAlN), chromium nitride (CrN), and aluminum chromium nitride (AlCrN), but aluminum chromium nitride (AlCrN) is preferable considering heat resistance to carrier gas temperature. The coatings described above are appropriately selected depending on the function required of the components.

[0062] (Operation of the CNT Manufacturing Apparatus) Next, an example of the operation of the CNT manufacturing apparatus 1 according to this embodiment will be described. The operation of the CNT manufacturing apparatus 1 described below is performed automatically by the control unit 100, but operations that can be performed by an operator may be performed by the operator's manual operation.

[0063] Figures 6 to 16 are diagrams illustrating an example of the operation of the CNT manufacturing apparatus 1, showing the operation of the CNT manufacturing apparatus 1 in chronological order. The CNT recovery apparatus 20 in each figure is shown in a more schematic manner than the apparatus in Figure 1, and some components are omitted from the illustration. In each figure, valves filled in black indicate the closed state, and valves outlined in white indicate the open state.

[0064] First, as shown in Figure 6, before a predetermined amount of CNT windings R are stored in the recovery chamber 40, the shutter 80 is open and the partition door 60 is stopped in the retracted position. As a result, the CNT windings R formed in the winding chamber 30 pass through the door chamber 50 and fall down to the recovery chamber 40. In this process, it is preferable to supply an inactive gas to the pocket space inside the door chamber 50. This prevents floating CNTs moving with the carrier gas from flowing into the pocket space inside the door chamber 50, and suppresses malfunctions of the partition door 60 caused by the adhesion of floating CNTs.

[0065] Next, as shown in Figure 7, when a predetermined amount of CNT windings R are stored in the recovery chamber 40, the shutter 80 is closed in preparation for the recovery of the CNT windings R. Since CNT generation continues even after the shutter 80 is closed, the newly formed CNT windings R fall into the temporary storage space 32 of the winding chamber 30 without passing through the door chamber 50.

[0066] Next, as shown in Figure 8, the partition door 60 is moved from the retracted position to the closed position. At this time, the first cleaning unit 70 and the second cleaning unit 71 attached to the front end of the partition door 60 slide against the ceiling and bottom surfaces inside the door room 50 as the partition door 60 moves, so that the CNTs adhering to the ceiling and bottom surfaces inside the door room 50 are removed.

[0067] Subsequently, as shown in Figure 9, the partition door 60 is extended vertically, closing the first opening 51 and the second opening 52 of the door chamber 50. This isolates the atmosphere inside the winding chamber 30, the door chamber 50, and the recovery chamber 40. Also, since the valve 49 of the recovery chamber 40 is open, the carrier gas filling the recovery chamber 40 is discharged from the recovery chamber 40.

[0068] Next, as shown in Figure 10, an inert gas is supplied into the recovery chamber 40 to create an inert gas atmosphere inside the recovery chamber 40. Subsequently, as shown in Figure 11, the supply of inert gas is stopped and the recovery chamber 40 is evacuated. Subsequently, as shown in Figure 12, the vacuum evacuation is stopped by closing valve 49 and the recovery chamber 40 is returned to an atmospheric atmosphere by opening the pressure restoration valve 48. After that, the CNT winding body R is recovered from inside the recovery chamber 40.

[0069] Note that the step of supplying an inert gas to the recovery chamber 40 as shown in Figure 10 may be omitted. However, when hydrogen gas is used as the carrier gas, supplying an inert gas to the recovery chamber 40 once and then performing vacuum evacuation again will allow any carrier gas that may remain in the recovery chamber 40 to be discharged, thereby improving safety. Furthermore, to further improve safety, for example, a hydrogen concentration meter (not shown) may be installed in the exhaust line leading to the exhaust port 46 of the recovery chamber 40 to monitor the hydrogen concentration of the atmospheric gas discharged during vacuum evacuation as shown in Figure 11.

[0070] Furthermore, as shown in Figure 12, when recovering the CNT winding body R from the recovery chamber 40, both the supply and exhaust of inert gas in the door chamber 50 are stopped. It is preferable that the pressure inside the door chamber 50 at this time is greater than atmospheric pressure. This increases the force with which the partition door 60 is pressed against the bottom surface inside the door chamber 50. As a result, even if a malfunction or other abnormality occurs in the components of the partition door 60 or the drive components for moving the partition door 60, the atmosphere inside the door chamber 50 and the atmosphere inside the recovery chamber 40 can be kept isolated.

[0071] For example, when the pressure inside the door chamber 50 measured by the pressure gauge 57 is greater than a predetermined pressure equal to or greater than atmospheric pressure, the supply of inert gas to the door chamber 50 may be stopped. When the pressure inside the door chamber 50 is less than the predetermined pressure, the supply of inert gas to the door chamber 50 may be supplied to increase the pressure inside the door chamber 50. By performing such control, the pressure inside the door chamber 50 is adjusted to avoid the pressure falling below atmospheric pressure, so that the partition door 60 can be kept pressed against the bottom surface inside the door chamber 50 during the recovery of the CNT winding body R.

[0072] From the viewpoint of maintaining a constant pressure greater than atmospheric pressure within the door chamber 50, the above-mentioned predetermined pressure is preferably greater than atmospheric pressure and 10 kPaG or less. Note that pressure adjustment within the door chamber 50 is not limited to methods involving the supply and cessation of inert gas; for example, it may be performed by adjusting the exhaust flow rate within the door chamber 50 while continuing to supply inert gas. Furthermore, when monitoring the pressure within the door chamber 50 with the supply and exhaust of inert gas stopped, a drop in pressure within the door chamber 50 can indicate a decrease in the sealing performance of the partition door 60 or a gas leak from another location. In other words, monitoring the pressure within the door chamber 50 provides a guideline for when maintenance should be initiated.

[0073] After the recovery of the CNT windings R is completed and the recovery chamber 40 is sealed from the atmosphere, the recovery chamber 40 is evacuated as shown in Figure 13 to remove the air inside. Subsequently, as shown in Figure 14, the vacuum evacuation of the recovery chamber 40 is stopped and an inert gas is supplied into the recovery chamber 40. After that, the vacuum evacuation of the recovery chamber 40 as shown in Figure 13 and the supply of inert gas to the recovery chamber 40 as shown in Figure 14 are repeated to create an inert gas atmosphere inside the recovery chamber 40. By repeating the vacuum evacuation and supply of inert gas inside the recovery chamber 40 twice in this way, residual air inside the recovery chamber 40 can be more reliably removed, and adverse effects on CNT quality caused by contact with oxygen can be suppressed. Furthermore, to improve safety, for example, an oxygen concentration meter (not shown) may be installed in the exhaust line leading to the exhaust port 46 of the recovery chamber 40 to monitor the oxygen concentration of the atmospheric gas discharged during the vacuum evacuation shown in Figure 13.

[0074] Next, the partition door 60, which had been blocking the first opening 51 and the second opening 52, is retracted vertically, moving the partition door 60 from the closed position to the retracted position, as shown in Figure 15. The supply of inert gas into the door room 50 is also resumed.

[0075] Subsequently, as shown in Figure 16, the shutter 80 covering the upper part of the first opening 51 is opened. As a result, all of the CNT windings R accumulated on the upper surface of the shutter 80 in the temporary storage space 32 fall into the recovery chamber 40, and any newly formed CNT windings R in the winding chamber 30 also pass through the door chamber 50 and fall into the recovery chamber 40. The system then returns to the state shown in Figure 6, and this state is maintained until a predetermined amount of CNT windings R is stored in the recovery chamber 40.

[0076] An example of the operation of the CNT manufacturing apparatus 1 according to this embodiment has been described above. The CNT recovery apparatus 20 according to this embodiment is provided with a door chamber 50 containing a partition door 60 between the winding chamber 30 and the recovery chamber 40. Furthermore, within the door chamber 50, there is provided a first cleaning unit 70 that is slidable against the ceiling surface around the first opening 51 and a second cleaning unit 71 that is slidable against the bottom surface around the second opening 52.

[0077] The first cleaning unit 70 and the second cleaning unit 71 slide along the ceiling and bottom surfaces inside the door room 50, thereby removing CNTs adhering to the ceiling and bottom surfaces inside the door room 50. In other words, since the CNTs adhering to the sealing surface can be removed before the first opening 51 and the second opening 52 are closed by the partition door 60, a decrease in the sealing performance of the sealing surface can be suppressed.

[0078] Although embodiments of the present invention have been illustrated above, the present invention is not limited to these examples. It will be obvious to those skilled in the art that various modifications or alterations can be conceived within the scope of the technical idea described in the claims, and these will naturally also fall within the technical scope of the present invention.

[0079] For example, the constituent elements of the above embodiment can be combined in any way. From such any combination, the functions and effects of each constituent element in the combination will naturally be obtained, as well as other functions and effects that will be obvious to those skilled in the art from the description herein.

[0080] Furthermore, the effects described herein are merely descriptive or illustrative and not limiting. In other words, the technology relating to this disclosure may produce other effects that are obvious to those skilled in the art from the description herein, in addition to or instead of the effects described herein.

[0081] The following configuration examples also fall within the technical scope of this disclosure: (1) A carbon nanotube recovery apparatus for recovering generated carbon nanotubes, comprising: a winding chamber on which the carbon nanotubes are wound; a recovery chamber provided below the winding chamber for recovering the carbon nanotubes; a partition door that separates the atmosphere in the winding chamber from the atmosphere in the recovery chamber; a door chamber in which the partition door is stored, having a first opening leading to the winding chamber and a second opening leading to the recovery chamber; a shielding member provided between the winding chamber and the door chamber that can open and close the first opening; a moving mechanism for moving the partition door between a retracted position that does not close the first and second openings and a closed position that does close them; a first cleaning unit made of an elastic body that is slidably provided with respect to the ceiling surface of the door chamber around the first opening; and a second cleaning unit made of an elastic body that is slidably provided with respect to the bottom surface of the door chamber around the second opening. (2) The carbon nanotube recovery apparatus according to (1), wherein the partition door comprises a first plate that closes the first opening, a second plate that closes the second opening, a first sealing material provided on the upper surface of the first plate, and a second sealing material provided on the lower surface of the second plate, the first cleaning unit and the second cleaning unit being attached to the partition door, the first cleaning unit being positioned on the first opening side of the first sealing material in the retracted position, and the second cleaning unit being positioned on the second opening side of the second sealing material in the retracted position. (3) The carbon nanotube recovery apparatus according to (2), wherein the partition door further comprises a third plate between the first plate and the second plate, the first plate and the third plate, and the second plate and the third plate are connected by links, respectively. (4) The carbon nanotube recovery apparatus according to any one of (1) to (3), wherein an inert gas supply port is provided in the region on the retracted position side of the first opening and the second opening for supplying an inert gas.(5) A carbon nanotube recovery apparatus according to any one of (1) to (4), comprising: an inert gas supply port for supplying an inert gas into the door room; an exhaust port for discharging the atmosphere inside the door room; a pressure measuring unit for measuring the pressure inside the door room; and a control unit for adjusting and controlling the supply flow rate of the inert gas supplied to the inert gas supply port and the exhaust flow rate from the exhaust port, wherein the control unit controls to increase the pressure inside the door room when the pressure inside the door room is less than a predetermined pressure equal to or greater than atmospheric pressure when the first opening and the second opening are closed by the partition door. (6) A carbon nanotube manufacturing apparatus for generating and recovering carbon nanotubes, comprising: a generating apparatus for generating the carbon nanotubes; and a carbon nanotube recovery apparatus according to any one of (1) to (5).

[0082] This invention can be applied to carbon nanotube recovery and manufacturing apparatuses.

[0083] 1 Carbon nanotube manufacturing apparatus 10 Carbon nanotube generating apparatus 11 Reaction tube 12 Heater 20 Carbon nanotube recovery apparatus 30 Winding chamber 31 Winding space 32 Temporary storage space 33 Winding roller 34 Exhaust port 35 Valve 40 Recovery chamber 43 Recovery door 44 Inert gas supply port 45 Air supply port 46 Exhaust port 47 Valve 48 Restoration valve 49 Valve 50 Door chamber 51 First opening 52 Second opening 53 Inert gas supply port 54 Valve 55 Exhaust port 56 Valve 57 Pressure gauge 60 Partition door 61 Moving mechanism 62 First plate 62a Notch 63 Second plate 63a Notch 64 Third plate 65 Link 66 Link 67 First seal material 68 Second seal material 70 First cleaning section 71 Second cleaning section 72 Fixing member 73 Auxiliary member 80 Shutter 100 Control unit P1 Retracted position P2 Closed position R Carbon nanotube winding

Claims

1. A carbon nanotube recovery apparatus for recovering generated carbon nanotubes, comprising: a winding chamber on which the carbon nanotubes are wound; a recovery chamber located below the winding chamber for recovering the carbon nanotubes; a partition door that separates the atmosphere inside the winding chamber from the atmosphere inside the recovery chamber; a door chamber in which the partition door is housed, having a first opening leading to the winding chamber and a second opening leading to the recovery chamber; a shielding member provided between the winding chamber and the door chamber that can open and close the first opening; a moving mechanism for moving the partition door between a retracted position that does not close the first and second openings and a closed position that does close them; a first cleaning section made of an elastic body that is slidably provided with respect to the ceiling surface inside the door chamber around the first opening; and a second cleaning section made of an elastic body that is slidably provided with respect to the bottom surface inside the door chamber around the second opening.

2. The carbon nanotube recovery apparatus according to claim 1, wherein the partition door comprises a first plate that closes the first opening, a second plate that closes the second opening, a first sealing material provided on the upper surface of the first plate, and a second sealing material provided on the lower surface of the second plate, the first cleaning unit and the second cleaning unit are attached to the partition door, the first cleaning unit is positioned on the first opening side of the first sealing material in the retracted position, and the second cleaning unit is positioned on the second opening side of the second sealing material in the retracted position.

3. The carbon nanotube recovery apparatus according to claim 2, wherein the partition door further has a third plate between the first plate and the second plate, and the first plate and the third plate, and the second plate and the third plate are connected by links, respectively.

4. The carbon nanotube recovery apparatus according to claim 1, wherein an inert gas supply port is provided in the region on the side of the first opening and the second opening that is closer to the retracted position, for supplying an inert gas.

5. The carbon nanotube recovery apparatus according to claim 1, comprising: an inert gas supply port for supplying an inert gas to the door room; an exhaust port for discharging the atmosphere inside the door room; a pressure measuring unit for measuring the pressure inside the door room; and a control unit for adjusting and controlling the supply flow rate of the inert gas supplied to the inert gas supply port and the exhaust flow rate from the exhaust port, wherein the control unit controls the pressure inside the door room to increase the pressure inside the door room when the pressure inside the door room is less than a predetermined pressure equal to or greater than atmospheric pressure, while the first opening and the second opening are closed by the partition door.

6. A carbon nanotube manufacturing apparatus for generating and recovering carbon nanotubes, comprising: a generating apparatus for generating the carbon nanotubes; and a carbon nanotube recovery apparatus as described in claim 1.

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