Reactor and temperature control method for reactor

Abstract

To provide a reactor capable of appropriately controlling temperature, and to provide a temperature control method thereof.SOLUTION: The reactor includes a cylinder 101, a temperature adjustment unit 320, a heater unit 360, a sensor unit 350, and a control unit. The heater unit includes a heater 111U, a heater 111D, a heater 111R, and a heater 111L provided on the upper, lower, left, and right sides of the cylinder 101. The sensor unit 350 includes sensors provided on the upper, lower, left, and right sides of the cylinder 101. The temperature adjustment unit 320 performs feedback control so that the measured temperature of the sensor becomes the set temperature. When the temperature difference between the upper sensor and the lower sensor exceeds a threshold temperature, the set temperatures of the lower temperature regulator, the right temperature regulator, and the left temperature regulator are changed based on the measured temperature of the lower sensor.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a reactor and a method for controlling the temperature of the reactor. [Background technology]

[0002] Patent Document 1 discloses a reactor having a cylindrical reactor, which has a feed port for receiving raw materials and a discharge port for the reaction product. The raw materials are transported from the feed port to the discharge port by rotation of a screw provided inside the reactor. Furthermore, the reactor has a heating device provided around the reactor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-21677 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, a heating device heats the reactor, thereby controlling the temperature of the reactor. The heating device controls the temperature of the reactor at an intermediate portion between the supply port and the delivery port. The temperature is controlled so that the temperature varies along the axial direction. In such a reactor, it is desirable to control the reactor to a desired temperature.

[0005] The present disclosure has been made to solve such problems, and provides a reaction apparatus capable of appropriately controlling temperature and a temperature control method therefor. [Means for solving the problem]

[0006] A reaction apparatus according to the present disclosure comprises a cylinder having a supply port for raw materials and a discharge port for reaction products, a screw provided within the cylinder and rotating to transport the raw materials from the supply port to the discharge port, a heater unit arranged around the cylinder, a sensor unit provided to measure the temperature of the cylinder, and a control unit that controls the heater unit based on the temperature measured by the sensor unit, wherein the heater unit comprises a right-side heater arranged on the right side of the cylinder in a cross-sectional view perpendicular to the rotation axis of the screw, a left-side heater arranged on the left side of the cylinder in the cross-sectional view, an upper heater arranged above the cylinder in the cross-sectional view, and a lower heater arranged below the cylinder in the cross-sectional view, and the sensor unit comprises a right-side sensor provided to measure the temperature of the right side of the cylinder, and a left-side heater arranged on the left side of the cylinder in the cross-sectional view. a left sensor provided for measuring the temperature above the cylinder, an upper sensor provided for measuring the temperature above the cylinder, and a lower sensor provided for measuring the temperature below the cylinder, and the control unit includes a right temperature regulator that feedback-controls the right heater so that the temperature measured by the right sensor becomes a set temperature when the temperature of the cylinder is decreasing, a left temperature regulator that feedback-controls the left heater so that the temperature measured by the left sensor becomes the set temperature, an upper temperature regulator that feedback-controls the upper heater so that the temperature measured by the upper sensor becomes the set temperature, and a lower temperature regulator that feedback-controls the lower heater so that the temperature measured by the lower sensor becomes the set temperature when the temperature difference between the upper sensor and the lower sensor exceeds a threshold temperature, and changes the set temperatures of the lower temperature regulator, the right temperature regulator, and the left temperature regulator based on the temperature measured by the lower sensor.

[0007] The temperature control method for a reaction apparatus according to the present disclosure is a method for controlling the temperature of a reaction apparatus comprising: a cylinder having a supply port for raw materials and a discharge port for a reaction product; a screw provided in the cylinder and rotating to transport the raw materials from the supply port to the discharge port; a heater unit arranged around the cylinder; a sensor unit provided to measure the temperature of the cylinder; and a control unit that feedback-controls the heater unit based on the temperature measured by the sensor unit, wherein the heater unit comprises a right-side heater arranged on the right side of the cylinder in a cross-sectional view perpendicular to the rotation axis of the screw, a left-side heater arranged on the left side of the cylinder in the cross-sectional view, an upper heater arranged above the cylinder in the cross-sectional view, and a lower heater arranged below the cylinder in the cross-sectional view; The subunit includes a right sensor provided for measuring the temperature of the right side of the cylinder, a left sensor provided for measuring the temperature of the left side of the cylinder, an upper sensor provided for measuring the temperature of the upper side of the cylinder, and a lower sensor provided for measuring the temperature of the lower side of the cylinder, and includes: (A) a step of feedback controlling the right heater, the left heater, the upper heater, and the lower heater so that the measured temperatures of the right sensor, the left sensor, the upper sensor, and the lower sensor each become set temperatures; (B) a step of determining whether the temperature difference between the upper sensor and the lower sensor exceeds a threshold temperature; and (C) a step of changing the set temperatures in the feedback control of the right heater, the left heater, and the lower heater when the temperature difference exceeds the threshold temperature. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a reaction apparatus capable of appropriately controlling temperature and a method for controlling the temperature thereof. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view schematically showing the overall configuration of a reaction apparatus. [Figure 2] FIG. 2 is a perspective view schematically illustrating the configuration of a temperature control device. [Figure 3] FIG. 1 is a cross-sectional view schematically showing the configuration of a reaction apparatus. [Figure 4] FIG. 10 is a side view schematically showing a configuration when a temperature difference occurs in the cylinder. [Figure 5] FIG. 10 is a side view schematically showing a configuration in which the temperature of the cylinder is uniform. [Figure 6] FIG. 2 is a block diagram showing a control system of the temperature control device. [Figure 7] 10 is a flowchart illustrating a temperature control method. [Figure 8] 10 is a table showing measured temperatures and set temperatures during temperature drop. [Figure 9] 1 is a graph schematically showing a temperature decrease pattern of a stepwise temperature decrease. [Figure 10] 10 is a graph showing steps in a temperature control method according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described below through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential means for solving the problems. For clarity of explanation, the following description and drawings have been omitted and simplified as appropriate. Note that in each drawing, the same elements are given the same reference numerals, and duplicate explanations are omitted as necessary.

[0011] Embodiment 1 The main configuration of a reaction apparatus 10 according to the first embodiment will be described with reference to FIG. 1. FIG. 1 is a side view schematically illustrating the configuration of the reaction apparatus 10 according to the first embodiment. The reaction apparatus 10 illustrated in the figure has been appropriately simplified for clarity of explanation. The reaction apparatus 10 is an apparatus for producing a reaction product by applying conditions such as a predetermined physical stimulus to, for example, powdered or granular raw materials. Here, the reaction apparatus 10 has reactors 100 and 200 arranged in two stages, one above the other. The reactors 100 and 200 are high-temperature reactors that heat the raw materials to a high temperature and cause them to react.

[0012] Since the upper reactor 100 and the lower reactor 200 have the same configuration, the following description will mainly focus on the configuration of the reactor 100, and the configuration of the reactor 200 will be omitted as appropriate. Of course, the reaction apparatus 10 may have only one reactor 100, or may have three or more reactors.

[0013] The reactor 10 produces a reaction product by reacting raw materials at high temperatures. For example, the reactor 10 functions as a CNT production device that produces CNTs (Carbon Nanotubes) using ceramics or other raw materials. The reactor 10 may be a production device for producing ceramic powder, battery materials, activated carbon, magnetic powder, pigments, fertilizers, medicines, or the like. Alternatively, the reactor 10 may be a processing device for plastic recycling, metal powder activation, or the like.

[0014] The reactor 100 includes a cylinder 101, a screw 106, a drive motor 109, and a temperature control device 150. The cylinder 101 is a hollow cylindrical member arranged horizontally. The cylinder 101 may be made of an alloy primarily containing nickel or chromium, or ceramics containing alumina. A supply port 102 for raw materials is provided at one end of the cylinder 101, and an outlet 103 for the reaction product is provided at the other end. The side with the supply port 102 is the upstream side, and the side with the outlet 103 is the downstream side. The internal space of the cylinder 101 is a reaction space in which the raw materials react. The supply port 102 is arranged facing upward, and the outlet 103 is arranged facing downward.

[0015] A screw 106 is provided inside the cylinder 101. The screw 106 is supported by a rotation shaft 107 in the cylinder 101. The rotation shaft 107 of the screw 106 is arranged along the axial direction of the cylinder 101. The rotation shaft 107 coincides with the central axis of the cylindrical cylinder 101. The rotation shaft 107 is connected to a drive motor 109. The drive motor 109 rotates the screw 106 around the rotation shaft 107. For example, the screw 106 can be made of an alloy mainly composed of nickel or chromium, or ceramics containing alumina.

[0016] A raw material is supplied from the supply port 102. For example, the raw material may be a powder, a fluid, beads, or the like. The raw material may be an inorganic material such as ceramic, or an organic material such as hydrocarbon. The raw material may be a metal oxide or metal sulfide containing lithium as one of its components. Furthermore, not only the raw material but also a catalyst or the like may be supplied from the supply port 102.

[0017] As the screw 106 rotates, the raw material is transported inside the cylinder 101. That is, as the screw 106 rotates, the raw material fed from the supply port 102 advances toward the delivery port 103. In FIG. 1, the raw material inside the cylinder 101 is delivered from the left side to the right side. Note that the cylinder 101 may be provided with two or more supply ports 102 or delivery ports 103. Furthermore, a plurality of raw materials may be fed from the supply port 102.

[0018] Gas pipes 104 and 105 are provided between the supply port 102 and the delivery port 103 in the axial direction. The multiple pipes 104 and the multiple pipes 105 are connected to the sidewall of the cylinder 101. The pipe 104 is attached to the lower side of the cylinder 101. The pipe 105 is attached to the upper side of the cylinder 101. Gases such as nitrogen gas (N2) and hydrogen gas (H2) are supplied to the internal space of the cylinder 101 from the pipes 104 and 105. Alternatively, gas in the internal space may be discharged to the outside from the pipes 104 and 105. Note that gas pipes may be provided only on the upper or lower side of the cylinder 101. The pipes 104 and 105 may be provided with gas nozzles that spray gas. The pipes 104 and 105 are arranged at multiple positions in the axial direction.

[0019] The reactor 100 is equipped with a temperature control device 150 for controlling the temperature of the cylinder 101. The temperature control device 150 has temperature control regions 110, 120, 130, and 140. The temperature control regions 110, 120, 130, and 140 are regions between the supply inlet 102 and the discharge outlet 103. The temperature control regions 110, 120, 130, and 140 are regions whose temperatures can be controlled independently. In the axial direction, the temperature control region 110 is closest to the supply inlet 102, and the temperature control region 140 is closest to the discharge outlet 103. The temperature control region 120 is adjacent to the temperature control region 110. The temperature control region 130 is located between the temperature control region 120 and the temperature control region 140. In other words, the cylinder 101 is divided into four temperature control regions 110, 120, 130, and 140 in the axial direction.

[0020] As will be described later, each of the temperature control regions 110, 120, 130, and 140 includes a heater, a temperature sensor, a temperature regulator, and the like. The temperature control regions 110, 120, 130, and 140 control the heater output so that the cylinder 101 reaches a predetermined temperature. For example, the temperature control regions 110, 120, and 130 control the temperature of the cylinder 101 to 500°C, and the temperature control region 140 controls the temperature of the cylinder 101 to 800°C. With the above-described configuration, the temperature control regions 110, 120, 130, and 140 control the temperature so that the cylinder 101 has various temperature distributions along the axial direction.

[0021] In this way, the cylinder 101 is divided into four zones in the axial direction, and the temperature is controlled in each zone. The zone in which the temperature control region 110 performs temperature control is also referred to as the first zone. The zones in which the temperature control regions 120, 130, and 140 perform temperature control are also referred to as the second zone, third zone, and fourth zone, respectively. The first to fourth zones may have different sizes in the axial direction. The axial lengths of the temperature control regions 110, 120, 130, and 140 may be the same or different. The set temperatures of the temperature control regions 110, 120, 130, and 140 can be set appropriately depending on the process being performed.

[0022] The temperature control device 150 then heats the cylinder 101 to the desired process temperature. Raw materials are fed into the cylinder 101 through the supply port 102. When the drive motor 109 rotates the screw 106 around the rotation axis 107, the raw materials pass through the internal space of the cylinder 101, which has been heated to the desired temperature. This promotes the reaction. Then, the reaction product produced by the reaction is discharged to the outside of the cylinder 101 through the discharge port 103. The reaction product discharged from the discharge port 103 is supplied to the reactor 200.

[0023] The reactor 200 includes a cylinder 201, a screw 206, a drive motor 209, and a temperature control device 250. As described above, the lower reactor 200 has the same configuration as the upper reactor 100. Therefore, the cylinder 201, the screw 206, the drive motor 209, and the temperature control device 250 of the reactor 200 correspond to the cylinder 101, the screw 106, the drive motor 109, and the temperature control device 150 of the reactor 100. Therefore, the cylinder 201 is provided with a supply port 202 and a delivery port 203. In addition, gas pipes 204 and 205 are connected to the cylinder 201.

[0024] When the drive motor 209 rotates the screw 206 around the rotation shaft 207, the raw material is transported inside the cylinder 201. That is, the raw material is fed into the supply port 202 of the cylinder 201 and is sent out to the delivery port 203. In FIG. 1, the raw material is sent out from the right side to the left side.

[0025] The temperature control device 250 has four temperature control regions 210, 220, 230, and 240. The temperature control regions 210, 220, 230, and 240 are arranged along the axial direction. Therefore, the cylinder 201 is divided into four zones in the axial direction and temperature controlled. Each temperature control region is equipped with a temperature sensor and a heater. The temperature control device 250 performs feedback control of the heater based on the temperature measured by the temperature sensor.

[0026] Here, the reaction product produced in reactor 100 is introduced into reactor 200. The outlet 103 of reactor 100 is disposed directly above the supply port 202 of reactor 200. Of course, the outlet 103 and the supply port 202 may be connected by a pipe or the like. Then, the reaction product produced in reactor 200 is delivered from the outlet 103 to the recovery tank 500.

[0027] In the upper reactor 100, ethylene gas (C2H4), hydrogen gas (H2), nitrogen gas (N2), etc. are introduced into a cylinder 101 from pipes 104 and 105. Then, raw material beads are transported downstream by a screw 106 while being heated.

[0028] In the lower reactor 200, ethylene gas, hydrogen gas, nitrogen gas, etc. are introduced into the cylinder 201 through pipes 204 and 205. The beads are heated and transported downstream by a screw 206. CNTs are produced by reactions in the upper reactor 100 and the lower reactor 200. Of course, the reactor 10 may be used for purposes other than the production of CNTs.

[0029] The axial direction of cylinder 101 and the axial direction of cylinder 201 may be inclined. For example, cylinder 101 and cylinder 201 may be arranged in a V-shape when viewed from above. Furthermore, although the number of temperature control regions is four in temperature control device 150 and temperature control device 250, the number of temperature control regions is not particularly limited. There may be one temperature control region, or two or more temperature control regions.

[0030] Next, the configuration of the temperature control device 150 will be described with reference to FIG. 2. FIG. 2 is a perspective view that schematically shows the configuration of the temperature control device 150. For clarity of explanation, FIG. 2 omits the supply port 102, the delivery port 103, the piping 104, the piping 105, the screw 106, and the like. Note that the following explanation will be made using an XYZ three-dimensional Cartesian coordinate system. The axial direction of the cylinder 101 is defined as the Z direction, and a cross section perpendicular to the Z direction is defined as the XY plane. The +Y direction is defined as the upward direction, and the -Y direction is defined as the downward direction. Furthermore, the +X direction is defined as the rightward direction, and the -X direction is defined as the leftward direction.

[0031] As described above, the temperature control device 150 has temperature control regions 110, 120, 130, and 140. Four heaters 111U, 111D, 111R, and 111L are provided in the temperature control region 110. The heater 111U is disposed above the cylinder 101. The heater 111D is disposed below the cylinder 101. The heater 111R is disposed to the right of the cylinder 101. The heater 111L is disposed to the left of the cylinder 101.

[0032] As described above, four heaters 111U, 111D, 111R, and 111L are arranged around the cylinder 101 in the XY plane. The heater 111U is also referred to as the upper heater, and the heater 111D is also referred to as the lower heater. Similarly, the heater 111R is also referred to as the right heater, and the heater 111L is also referred to as the left heater. The heaters 111U, 111D, 111R, and 111L are sheath heaters, ceramic heaters, coil heaters, lamp heaters, etc.

[0033] Furthermore, temperature control device 150 has temperature sensors 112U and 112R. Temperature sensor 112U is disposed above cylinder 101. Temperature sensor 112R is disposed to the right of cylinder 101. Temperature sensor 112U measures the temperature of the upper portion of cylinder 101, and temperature sensor 112R measures the temperature of the right portion of cylinder 101. Temperature sensor 112U is also referred to as the upper temperature sensor, and temperature sensor 112R is also referred to as the right temperature sensor.

[0034] Although not shown in Fig. 2, temperature sensors are provided on the lower and left sides of cylinder 101. The temperature sensor on the lower side of cylinder 101 is temperature sensor 112D, and the temperature sensor on the left side of cylinder 101 is temperature sensor 112L (see Fig. 3). Temperature sensors 112U, 112D, 112R, and 112L are, for example, thermocouples, and are attached to the outer circumferential surface of cylinder 101.

[0035] Furthermore, in the temperature control region 120, a heater 121U and a temperature sensor 122U are provided above the cylinder 101. A heater 121R and a temperature sensor 122R are provided on the right side of the cylinder 101. Although not shown in FIG. 2, a heater and a temperature sensor are also provided below and on the left side of the cylinder 101.

[0036] In the temperature control region 130, a heater 131U and a heater 131R are provided above and to the right of the cylinder 101. A heater 131R and a temperature sensor 132R are provided to the right of the cylinder 101. Although not shown in FIG. 2, a heater and a temperature sensor are also provided below and to the left of the cylinder 101, respectively.

[0037] In the temperature control region 140, a heater 141U and a heater 141R are provided above and to the right of the cylinder 101. A heater 121R and a temperature sensor 122R are provided to the right of the cylinder 101. Although not shown in FIG. 2, a heater and a temperature sensor are also provided below and to the left of the cylinder 101, respectively.

[0038] Fig. 3 is an XY cross-sectional view schematically showing the arrangement of heaters and temperature sensors around the cylinder 101. Fig. 3 shows the XY cross-section of the temperature control region 110. The other temperature control regions 120, 130, and 140 have the same arrangement as the temperature control region 110, and therefore their explanations are omitted.

[0039] The heater 111U is disposed above the cylinder 101 and heats the upper portion of the cylinder 101. The heater 111D is disposed below the cylinder 101 and heats the lower portion of the cylinder 101. The heater 111R is disposed to the right of the cylinder 101 and heats the right portion of the cylinder 101. The heater 111L is disposed to the left of the cylinder 101 and heats the left portion of the cylinder 101.

[0040] Temperature sensor 112U is attached to the upper side of cylinder 101 and measures the temperature of the upper portion of cylinder 101. Temperature sensor 112D is attached to the lower side of cylinder 101 and measures the temperature of the lower portion of cylinder 101. Temperature sensor 112R is attached to the right side of cylinder 101 and measures the temperature of the right portion of cylinder 101. Temperature sensor 112L is attached to the left side of cylinder 101 and measures the temperature of the left portion of cylinder 101.

[0041] Heater 111U is feedback controlled based on the temperature measured by temperature sensor 112U. Heater 111D is feedback controlled based on the temperature measured by temperature sensor 112D. Heater 111R is feedback controlled based on the temperature measured by temperature sensor 112R. Heater 111L is feedback controlled based on the temperature measured by temperature sensor 112L.

[0042] Pipes 104 and 105 are attached to the cylinder 101. Two pipes 104 are provided below the cylinder 101. In the XY cross section, the two pipes 104 are attached in a V-shape. The pipes 104 pass through the lower heater 111D. One pipe 105 is provided above the cylinder 101. The pipe 105 extends in the +Y direction and passes through the upper heater 111U. The arrangement and number of the pipes 104 and 105 are not particularly limited.

[0043] Similarly to the temperature control region 110, the temperature control region 120 also has four heaters and four temperature sensors. Similarly to the temperature control region 110, the temperature control region 130 also has four heaters and four temperature sensors. Similarly to the temperature control region 110, the temperature control region 140 also has four heaters and four temperature sensors. Therefore, the temperature control device 150 has 16 heaters and 16 temperature sensors. The temperature control device 150 has 16 feedback control loops. Of course, the number of heaters and temperature sensors is not particularly limited.

[0044] In each of the temperature control regions 110, 120, 130, and 140, four heaters and four temperature sensors are arranged around the cylinder 101 in the XY cross section. Each heater is feedback-controlled according to the temperature measured by the corresponding temperature sensor. This makes it possible to make the temperature distribution uniform in the XY cross section. This also makes it possible to suppress deformation of the cylinder 101 due to the temperature distribution.

[0045] For example, FIG. 4 is a schematic diagram showing the configuration of the reactor 100 in a YZ cross section, illustrating a case where a temperature distribution occurs in the Y direction. In the temperature control region 110, the upper temperature sensor 112U measures a temperature of 300°C, and the lower temperature sensor 112D measures a temperature of 300°C. In the temperature control region 120, the upper temperature sensor 122U measures a temperature of 280°C, and the lower temperature sensor 122D measures a temperature of 285°C. In the temperature control region 130, the upper temperature sensor 132U measures a temperature of 272°C, and the lower temperature sensor 132D measures a temperature of 270°C. In the temperature control region 140, the upper temperature sensor 142U measures a temperature of 300°C, and the lower temperature sensor 142D measures a temperature of 300°C.

[0046] While there is no temperature difference between the top and bottom in the temperature control regions 110 and 140, there is a temperature difference between the top and bottom in the temperature control regions 120 and 130. In this case, there is a risk that the cylinder 101 will be deformed due to the temperature difference between the top and bottom. In other words, if a temperature distribution occurs, the amount of deformation due to thermal expansion will change, causing the cylinder 101 to warp or bend. If the amount of deformation is large, there is a risk that the screw 106 will come into contact with the cylinder 101. In particular, when the temperature of the cylinder 101 is increased or decreased, the temperature distribution may become large.

[0047] Therefore, in this embodiment, the temperature control device 150 controls the temperature so that the temperature distribution of the cylinder 101 is uniform within the XY plane. Fig. 5 is a diagram showing a case where the temperature distribution is uniform. In Fig. 5, the temperatures measured by all the temperature sensors are 300°C. Therefore, because the temperature distribution is uniform, deformation of the cylinder 101 can be prevented.

[0048] 6 is a block diagram showing the control system of the temperature control device 150. The temperature control device 150 has a control unit 310, a temperature adjustment unit 320, a heater driving unit 340, a sensor unit 350, and a heater unit 360. As described above, four heaters are provided in each of the four temperature control regions 110, 120, 130, and 140. In other words, the cylinder 101 is provided with 16 heaters and 16 temperature sensors, and therefore 16 feedback control loops are formed.

[0049] Temperature control area 110 is provided with upper, lower, left, and right heaters 111U, 111D, 111L, and 111R and upper, lower, left, and right temperature sensors 112U, 112D, 112L, and 112R. Temperature control area 120 is provided with upper, lower, left, and right heaters 121U, 121D, 121L, and 121R and upper, lower, left, and right temperature sensors 122U, 122D, 122L, and 122R. Temperature control area 130 is provided with upper, lower, left, and right heaters 131U, 131D, 131L, and 131R and upper, lower, left, and right temperature sensors 132U, 132D, 132L, and 132R. The temperature control area 140 is provided with upper, lower, left and right heaters 141U, 141D, 141L, and 141R, and upper, lower, left and right temperature sensors 142U, 142D, 142L, and 142R.

[0050] The sensor unit 350 includes 16 temperature sensors 112U, 112D, 112L, 112R, 122U, 122D, 122L, 122R, 132U, 132D, 132L, 132R, 142U, 142D, 142L, and 142R. The heater unit 360 includes 16 heaters 111U, 111D, 111L, 111R, 121U, 121D, 121L, 121R, 131U, 131D, 131L, 131R, 141U, 141D, 141L, and 141R.

[0051] Four feedback control loops are provided in the temperature control region 110 to control the upper, lower, left, and right heaters 111U, 111D, 111L, and 111R. For clarity, only one feedback control loop will be described here. In other words, the control described below is applicable to all 16 heaters. In one feedback control loop, a heater is controlled based on the temperature measured by one temperature sensor. For example, the heater 111U is feedback-controlled based on the temperature measured by the temperature sensor 112U.

[0052] The control unit 310 is a programmable logic controller (PLC) or the like, and controls the temperature control device 150 and the entire reaction device 10. For example, the control unit 310 controls the timing of starting and stopping heating, starting cooling, etc. The control unit 310 outputs a set temperature according to the process to the temperature regulator 321. Temperatures measured by 16 temperature sensors are input to the control unit 310. The control unit 310 controls the drive motor 109 and the like. Note that at least some of the functions of the temperature adjustment unit 320 and heater drive unit 340, which will be described later, may be executed as software processing in the PLC.

[0053] The temperature adjustment unit 320 has a temperature regulator 321. The temperature regulator 321 may be a general-purpose PID (Proportional-Integral-Differential) temperature regulator or the like. Alternatively, the processing of the temperature regulator 321 may be performed by software processing such as a PLC. As described above, since 16 feedback control loops are provided, the temperature adjustment unit 320 has 16 temperature regulators 321. For example, in the temperature control region 110, a temperature regulator 321 is provided for each of the upper heater 111U, the lower heater 111D, the right heater 111R, and the left heater 111L. The first temperature regulator 321 is provided in the feedback control loop of the heater 111U in the temperature control region 110. Furthermore, the 16 temperature regulators 321 do not have to be physically separate devices.

[0054] The temperature regulators 321 are set with PID parameters according to the cylinder 101 and heater. Furthermore, the control unit 310 sets the set temperature (SV: Setting Value) for each temperature regulator 321. The temperature regulators 321 perform feedback control based on the deviation between the set temperature SV and the temperature measured by the temperature sensor (PV: Process Variable). In other words, the temperature regulators 321 use the PID parameters to calculate the control output (MV: Manipulated Variable) from the deviation, the derivative of the deviation, and the integral of the deviation. Here, a known feedback control method can be used, and therefore a description thereof will be omitted.

[0055] As described above, since 16 feedback control loops are provided, the heater driving unit 340 has 16 heater driving sections 341. For example, in the temperature control region 110, a heater driving section 341 is provided for each of the upper heater 111U, the lower heater 111D, the right heater 111R, and the left heater 111L. For example, the first heater driving section 341 is provided in the feedback control loop of the heater 111U in the temperature control region 110.

[0056] The heater driving unit 341 drives the heater based on the control output MV from the temperature regulator 321. The heater driving unit 341 has a power supply for supplying a current to the heater. The heater driving unit 341 supplies a current to the heater according to the control output MV. The heater is heated by the current flowing through the heater. Therefore, the heater is feedback-controlled so that the temperature measured by the temperature sensor approaches the set temperature. The temperature control device 150 controls the temperature of the cylinder 101 to a desired temperature.

[0057] Here, in the reaction apparatus 10, the temperature of the cylinder 101 may be lowered for process changes, maintenance, or the like. For example, when a process change is made, the temperature control device 150 lowers the process temperature from 700°C to 500°C, which is the process temperature of a different process. When maintenance is to be performed, the temperature control device 150 lowers the temperature of the cylinder 101 to a temperature at which maintenance can be performed, for example, room temperature. When the temperature of the cylinder 101 is lowered, the temperature control device 150 performs feedback control so that the temperature distribution in each zone is uniform.

[0058] The temperature control method by the temperature control device 150 will be described in detail with reference to FIGS. 7 and 8. FIG. 7 is a flowchart showing the temperature control method. FIG. 8 is a table showing the measured temperature PV and the set temperature SV at each step. In FIG. 8, the measured temperature changes in the order of Table T1, Table T2, Table T3, and Table T4. In the following explanation, it is assumed that the temperature regulator 321 performs feedback control in each feedback control loop so that the measured temperature PV approaches the set temperature SV. In the following explanation, control in the first zone, i.e., the temperature control region 110, will be described, but the temperature control device 150 can also perform similar control in the second to fourth zones.

[0059] When the temperature control device 150 starts decreasing the temperature of the cylinder 101, it sets the set temperature SV of the temperature regulator 321. Here, the set temperatures SV of all the temperature regulators 321 are set to the same temperature (500°C) (see T1 in FIG. 8). The control unit 310 determines whether the temperature difference between the measured temperature on the upper side and the measured temperature on the lower side is equal to or greater than a threshold temperature (S101). The measured temperature on the upper side is the temperature measured by the temperature sensor 112U. The measured temperature on the lower side is the temperature measured by the temperature sensor 112D. Here, the threshold temperature is set to 20°C. This threshold temperature is also referred to as a first threshold temperature TH1.

[0060] If the temperature difference is less than the threshold temperature (NO in S101), the process returns to step S101 (T1 in FIG. 8). Specifically, in table T1 in FIG. 8, the measured temperature on the upper side is 620°C, and the measured temperature on the lower side is 601°C. Therefore, the temperature difference is 19°C, which is lower than the threshold temperature. Therefore, the process returns to step S101, and the temperature control device 150 continues to lower the temperature by feedback control.

[0061] If the temperature difference is equal to or greater than the threshold temperature (YES in S101), the control unit 310 replaces the set temperature based on the PV value (S102). As shown in Table T2 in FIG. 8, the temperature difference becomes 20°C during temperature decrease. The control unit 310 changes the set temperature SV of the right, lower, and left sides to values ​​corresponding to the measured temperature PV of the lower temperature sensor 112D. Here, the set temperature SV of the right, lower, and left sides is increased from 500°C to the measured temperature PV of the lower side (599°C). Then, the temperature control device 150 continues to decrease the temperature by feedback control. Here, only the set temperature of the upper side, which has a slower temperature decrease rate, remains at 500°C.

[0062] Next, the control unit 310 determines whether the temperature difference between the measured temperatures on the upper and lower sides is less than the threshold temperature (S103). If the temperature difference is equal to or greater than the threshold temperature (NO in S103), the process returns to step S102. For example, in table T3 of FIG. 8, the temperature difference is 23°C, which is higher than the threshold temperature. Therefore, the control unit 310 maintains the value of the set temperature SV as is.

[0063] If the temperature difference is less than the threshold temperature (YES in S103), the set temperature SV is replaced based on the upper SV value (S104). As shown in Table T4 in FIG. 8, the temperature difference becomes 19°C during temperature decrease, which is lower than the threshold temperature. The control unit 310 changes the set temperature SVs of the right, lower, and left sides to values ​​corresponding to the upper set temperature SV. In this example, the set temperature SVs of the right, lower, and left sides are decreased from 599°C to the upper set temperature SV of 500°C. Then, the process returns to S101, and the temperature control device 150 continues decreasing the temperature through feedback control.

[0064] In this way, by changing the set temperatures SV of the right, left, and lower sides within the zone, the control unit 310 reduces the control output MV for the heaters 111R, 111L, and 111D. This allows the temperature drop rate of the right, lower, and left parts of the cylinder 101 to be slowed. Therefore, the measured temperature PV of the upper side of the cylinder 101 approaches the measured temperatures PV of the right, lower, and left sides. In other words, by changing the set temperatures SV of the right, left, and lower sides, the temperature drop rate of the upper side of the cylinder 101 can be made faster than the temperature drop rate of the right, left, and lower sides.

[0065] In this way, the temperature control device 150 can appropriately control the temperature of the cylinder 101. Specifically, the temperature distribution of the cylinder 101 can be made uniform in the temperature control region 110. That is, the temperature distribution becomes uniform in the XY cross section. Therefore, as shown in FIGS. 4 and 5, deformation of the cylinder 101 can be suppressed.

[0066] Here, the temperature drop rate tends to be slower in the upper part of the cylinder 101 than in other parts. For example, the temperature drop rate is relatively faster in the lower part of the cylinder 101 because multiple pipes 104 are provided therein. The temperature drop rate in the upper part of the cylinder 101 is slower than the temperature drop rates in the lower, right, and left parts. Therefore, in this embodiment, the temperature control device 150 calculates the temperature difference between the measured temperatures in the upper and lower parts. When the temperature difference becomes larger than the threshold temperature, the control unit 310 changes the set temperatures for the lower, right, and left parts to slow the temperature drop rate. In this way, the temperature drop in the upper part, which has a slower temperature drop rate, waits for the temperature drop in the upper part to finish before the temperature drop in the lower, right, and left parts begins. Therefore, the temperature of the cylinder 101 can be lowered with a uniform temperature distribution.

[0067] The same control as that for temperature control region 110 is performed for temperature control regions 120, 130, and 140. That is, if the temperature difference exceeds a threshold temperature, control unit 310 changes the set temperature SV. For example, control unit 310 calculates the temperature difference between the temperature measured by temperature sensor 122U and the temperature measured by temperature sensor 122D. Then, if the temperature difference exceeds the threshold, control unit 310 changes the set temperature SV for feedback control. In this way, the temperature distribution in the XY cross section can be made uniform, thereby suppressing deformation of cylinder 101.

[0068] Furthermore, the temperature control device 250 can perform the same control as the temperature control device 150. The temperature control device 250 also performs the same temperature control for the reactor 200. In this way, the temperatures of the reactors 100 and 200 can be appropriately controlled. Since deformation of the cylinders 101 and 201 can be prevented, the productivity of CNTs and the like can be improved.

[0069] The number of zones is not limited to four, but may be at least one. Of course, the cylinder 101 may be divided into two or more zones.

[0070] Embodiment 2 A description will be given of the reaction apparatus 10 and the temperature control method thereof according to embodiment 2. Note that the basic configurations of the reaction apparatus 10 and the temperature control device 150 are the same as those in embodiment 1, and therefore the description will be omitted.

[0071] In the second embodiment, the temperature control device 150 performs a stepwise temperature decrease in which the set temperature of the temperature adjustment unit 320 decreases toward the target temperature. For example, as shown in Fig. 9, a temperature decrease pattern is set so that the set temperature of the temperature adjuster 321 changes over time. In Fig. 9, the horizontal axis represents time and the vertical axis represents the temperature of the SV.

[0072] In Figure 9, the set temperature SV reaches the target temperature through five steps. The target temperature is, for example, the process temperature. Time A to time B is the first step, time B to time C is the second step, and time C to time D is the third step. Time D to time E is the fourth step, and time E to time F is the fifth step.

[0073] During the period from time A to time B (also called the first step period), the set temperature SV is constant at SV1. During the period from time B to time C (also called the second step period), the set temperature SV is constant at SV2. During the period from time C to time D (also called the third step period), the set temperature SV is constant at SV3. During the period from time D to time E (also called the fourth step period), the set temperature SV is constant at SV4. During the period from time E to time F (also called the fifth step period), the set temperature SV is constant at SV5. In this way, the set temperature SV decreases in stages over time.

[0074] In FIG. 9, the step periods of each step are the same, but they may be different. For example, the first step period and the second step period may have the same time width or different time widths. Also, in FIG. 9, the temperature drop temperatures for each step are the same, but they may be different temperatures. For example, the difference between SV1 and SV2 may be the same as the difference between SV2 and SV3, or they may be different.

[0075] The number of steps in the step temperature decrease, the step time, and the value of the set temperature SV at each step are not particularly limited. For example, the control unit 310 sets a temperature decrease pattern in the temperature regulator 321 that changes the set temperature SV by 1°C every minute. The control unit 310 sets the same temperature decrease pattern for all the temperature regulators 321.

[0076] The temperature control areas 110, 120, 130, and 140 are zones in which the temperature is controlled. For example, the zone of temperature control area 110 is zone 1. Similarly, the zones of temperature control areas 120, 130, and 140 are zone 2, zone 3, and zone 4, respectively.

[0077] The control unit 310 calculates the difference between the maximum and minimum temperatures measured by the temperature sensors in one zone. The maximum temperature is, for example, the highest temperature measured by the temperature sensors 112U, 112D, 112L, and 112R on the top, bottom, left, and right sides. The minimum temperature is the lowest temperature measured by the four temperature sensors 112U, 112D, 112L, and 112R on the top, bottom, left, and right sides. The control unit 310 calculates the difference between the maximum and minimum values ​​as the intra-zone temperature difference. The control unit 310 calculates the intra-zone temperature difference for each zone. In this example, since there are four zones, the control unit 310 calculates four intra-zone temperature differences. The control unit 310 compares the intra-zone temperature difference with a predetermined value (hereinafter referred to as threshold value TH2). If the intra-zone temperature difference exceeds threshold value TH2, the control unit 310 stops the stepwise temperature decrease.

[0078] Specifically, as shown in FIG. 10, assume that the temperature difference within the zone exceeds the threshold value TH2 immediately after time C. Here, the threshold value TH2 is set to 25°C, and is also referred to as the second threshold value. Immediately after time C, the temperature variation in the cylinder 101 increases, and the temperature difference within the zone exceeds the second threshold value. Therefore, the control unit 310 stops the step progress in the temperature adjustment unit. In this case, the third step period from time C to time D becomes longer than the initial setting value.

[0079] While the step progress is stopped, the control unit 310 compares the temperature differences in all zones with a predetermined value (hereinafter referred to as threshold value TH3). When the temperature differences in all zones become equal to or less than threshold value TH3, the control unit 310 resumes the step progress. In FIG. 11, threshold value TH3 is set to 15°C. Threshold value TH3 is also referred to as the third threshold value. Threshold value TH3 is a value smaller than threshold value TH2. At time D1, the temperature difference in the zone reaches 15°C. Note that time D1 is later than time D in FIG. 10. Therefore, the period of the third step (time C to time D1) is longer than the periods of the other steps.

[0080] The control unit 310 resumes the stepwise temperature decrease at time D1. Here, time D1 is the start time of the fourth step, and the set temperature SV decreases. Then, at time E1, the fifth step begins. Note that the period between time D1 and time E1 has the same duration as the period between time D and time E in FIG. 10. In this way, the control unit 310 stops the stepwise temperature decrease until the in-zone temperature differences of all zones converge to a predetermined value. For example, the control unit 310 stops the stepwise temperature decrease timer.

[0081] In this way, the control unit 310 calculates the temperature difference in each zone. If the temperature difference in at least one zone exceeds the threshold value TH2, the control unit 310 stops the stepwise temperature decrease. The control unit 310 calculates the temperature difference in all zones.

[0082] Furthermore, when the temperature differences in all zones fall below the threshold value TH3, the control unit 310 restarts the stepwise temperature decrease of the temperature regulator 321. This makes it possible to make the temperature distribution of the cylinder 101 uniform in the cross-sectional direction. The temperature of the cylinder 101 can be decreased stepwise to the target temperature while maintaining the uniform temperature distribution of the cylinder 101 in the cross-sectional direction.

[0083] The temperature control device 150 may perform the temperature control of the second embodiment together with the temperature control of the first embodiment, or may perform the temperature control alone. By performing the temperature control of the second embodiment together with the temperature control of the first embodiment, the temperature distribution in the cross-sectional direction and the axial direction can be made uniform. Therefore, the temperature control device 150 can appropriately heat the cylinder 101, thereby preventing deformation of the cylinder 101, etc.

[0084] When the temperature differences in all zones become equal to or less than the threshold value TH3, the stepwise temperature decrease process resumes. This prevents the temperature decrease time from becoming too long. When the temperature control in the second embodiment is performed together with the temperature control in the first embodiment, the first threshold value is smaller than the second threshold value. The first threshold value is larger than the third threshold value. Of course, the values ​​of these threshold values ​​and their magnitude relationships are not particularly limited.

[0085] The temperature control of the first embodiment and the temperature control of the second embodiment may be performed independently. For example, in the first embodiment, the cylinder 101 may be cooled to the target temperature without using a step temperature decrease. Of course, in the first embodiment, the cylinder 101 may be cooled to the target temperature using a step temperature decrease.

[0086] Control of the temperature control device 150 can be achieved by a computer program or the like. For example, the control unit 310 executes the program, thereby performing at least a portion of the above-described processing. A program such as the control unit 310 includes a set of instructions (or software code) that, when loaded into a computer, causes the computer to perform one or more functions described in the embodiments. The program may be stored in a non-transitory computer-readable medium or a tangible storage medium. Examples of computer-readable media or tangible storage media include, but are not limited to, random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technology, CD-ROM, digital versatile disc (DVD), Blu-ray (registered trademark) disc or other optical disk storage, and magnetic storage devices. The program may also be transmitted on a transitory computer-readable medium or communication medium. Examples of transitory computer-readable media or communication media include, but are not limited to, electrical, optical, acoustic, or other forms of propagated signals.

[0087] The present invention is not limited to the above-described embodiment, and can be modified as appropriate within the scope of the invention. [Explanation of symbols]

[0088] 10. Reactor 100 reactor 101 Cylinder 102 Supply port 103 Outlet 104 Piping 105 Piping 106 screw 107 Rotational Axis 109 Drive motor 110 Temperature Control Area 111U Heater 111D Heater 111L heater 111R heater 112U Temperature Sensor 112D Temperature Sensor 112L Temperature Sensor 112R Temperature Sensor 120 temperature control areas 130 Temperature Control Area 140 Temperature Control Area 200 reactor 310 Control Unit 320 Temperature Control Unit 321 Temperature controller 340 Heater Drive Unit 341 Heater drive unit 350 Sensor Unit 360 heater unit

Claims

1. a cylinder having a raw material supply port and a reaction product discharge port; a screw provided in the cylinder and rotating to transport the raw material from a supply port to a delivery port; a heater unit disposed around the cylinder; a sensor unit provided for measuring the temperature of the cylinder; a control unit that controls the heater unit based on the temperature measured by the sensor unit; The heater unit comprises: a right heater disposed on the right side of the cylinder in a cross-sectional view perpendicular to the rotation axis of the screw; a left heater disposed on the left side of the cylinder in the cross-sectional view; an upper heater disposed above the cylinder in the cross-sectional view; a lower heater disposed below the cylinder in the cross-sectional view, The sensor unit includes: a right-side sensor for measuring the temperature of the right side of the cylinder; a left sensor provided for measuring the temperature of the left side of the cylinder; an upper sensor provided to measure the temperature of the upper side of the cylinder; a lower sensor provided to measure the temperature of the lower side of the cylinder; The control unit, when the temperature of the cylinder is decreasing, a right temperature regulator that performs feedback control of the right heater so that the temperature measured by the right sensor becomes a set temperature; a left temperature regulator that performs feedback control of the left heater so that the temperature measured by the left sensor becomes a set temperature; an upper temperature regulator that performs feedback control of the upper heater so that the temperature measured by the upper sensor becomes a set temperature; a lower temperature controller that performs feedback control of the lower heater so that the temperature measured by the lower sensor becomes a set temperature; When the temperature difference between the upper sensor and the lower sensor exceeds a threshold temperature, the set temperatures of the lower temperature regulator, the right temperature regulator, and the left temperature regulator are changed based on the temperature measured by the lower sensor. Reactor.

2. 2. The reactor according to claim 1, wherein a gas pipe for introducing or discharging gas is provided above or below the cylinder.

3. 3. The reaction apparatus according to claim 2, wherein when the temperature difference between the upper sensor and the lower sensor becomes equal to or less than a threshold temperature, the set temperatures of the lower temperature controller, the right temperature controller, and the left temperature controller are set based on the set temperature of the upper temperature controller.

4. When the temperature difference between the upper sensor and the lower sensor is equal to or less than a threshold temperature, the set temperatures of the upper sensor, the lower temperature regulator, the right-side temperature regulator, and the left-side temperature regulator are the same, 4. The reaction device according to claim 3, wherein when the temperature difference between the upper sensor and the lower sensor exceeds a threshold temperature, the set temperatures of the lower temperature regulator, the right temperature regulator, and the left temperature regulator are changed to the temperature measured by the lower sensor.

5. The reaction apparatus according to any one of claims 1 to 4, wherein the right-side temperature regulator, the left-side temperature regulator, the upper-side temperature regulator, and the lower-side temperature regulator perform feedback control so that the set temperature is decreased stepwise along a temperature decreasing pattern that changes over time.

6. The cylinder is divided into a plurality of zones in the axial direction, each of the plurality of zones is provided with the heater unit, the sensor unit, and the control unit; A temperature difference within the zone, which is the difference between the highest and lowest measured temperatures in the zone, is determined; 6. The reactor according to claim 5, wherein when the temperature difference in at least one zone exceeds a first predetermined value, the stepwise progress of the temperature decrease in all zones is stopped.

7. 7. The reactor according to claim 6, wherein the stepwise temperature decrease in all zones is resumed when the temperature difference in all zones becomes equal to or less than a second predetermined value that is lower than the first predetermined value.

8. a cylinder having a raw material supply port and a reaction product discharge port; a screw provided in the cylinder and rotating to transport the raw material from a supply port to a delivery port; a heater unit disposed around the cylinder; a sensor unit provided for measuring the temperature of the cylinder; a control unit that feedback-controls the heater unit based on the temperature measured by the sensor unit, The heater unit comprises: a right heater disposed on the right side of the cylinder in a cross-sectional view perpendicular to the rotation axis of the screw; a left heater disposed on the left side of the cylinder in the cross-sectional view; an upper heater disposed above the cylinder in the cross-sectional view; a lower heater disposed below the cylinder in the cross-sectional view, The sensor unit includes: a right-side sensor for measuring the temperature of the right side of the cylinder; a left sensor provided for measuring the temperature of the left side of the cylinder; an upper sensor provided to measure the temperature of the upper side of the cylinder; a lower sensor provided to measure the temperature of the lower side of the cylinder; (A) feedback-controlling the right heater, the left heater, the upper heater, and the lower heater so that the temperatures measured by the right sensor, the left sensor, the upper sensor, and the lower sensor are set to respective set temperatures; (B) determining whether a temperature difference between the upper sensor and the lower sensor exceeds a threshold temperature; (C) changing the set temperatures in the feedback control of the right heater, the left heater, and the lower heater when the temperature difference exceeds the threshold temperature.

9. 9. The method for controlling the temperature of a reaction apparatus according to claim 8, wherein a gas inlet for introducing gas is provided on the lower side of the cylinder.

10. 10. The temperature control method for a reaction apparatus according to claim 9, wherein when the temperature difference between the upper sensor and the lower sensor becomes equal to or less than a threshold temperature, the set temperatures in the feedback control of the right heater, the left heater, and the lower heater are set based on the set temperature in the feedback control of the upper heater.

11. When the temperature difference between the upper sensor and the lower sensor is equal to or less than a threshold temperature, the set temperatures in the feedback control of the right heater, the left heater, the lower heater, and the upper heater are the same temperature, 11. The temperature control method for a reaction apparatus according to claim 10, wherein when the temperature difference between the upper sensor and the lower sensor exceeds a threshold temperature, the set temperatures in the feedback control of the right heater, the left heater, and the lower heater are changed to the temperature measured by the lower sensor.

12. (A) In the feedback control step, The method for controlling the temperature of a reaction apparatus according to any one of claims 8 to 11, wherein feedback control is performed so that the set temperature is decreased stepwise along a temperature decrease pattern that changes with time.

13. The cylinder is divided into a plurality of zones in the axial direction, each of the plurality of zones is provided with the heater unit, the sensor unit, and the control unit; A temperature difference within the zone, which is the difference between the highest and lowest measured temperatures in the zone, is determined; 13. The method for controlling the temperature of a reactor according to claim 12, wherein when the temperature difference in at least one zone exceeds a first predetermined value, the stepwise progress of the temperature decrease in all zones is stopped.

14. 14. The temperature control method for a reactor according to claim 13, wherein when the temperature difference within all the zones becomes equal to or less than a second predetermined value that is lower than the first predetermined value, the stepwise temperature decrease is resumed in all the zones.

Images