TW202410962A - Decomposition apparatus, decomposition method, and method for producing decomposition product - Google Patents

Abstract

To provide a novel-mode decomposition apparatus for a raw material containing a saturated hydrocarbon as a main component, which makes it possible to make the decrease in heating efficiency associated with coking smaller. A decomposition apparatus 1 for decomposing a raw material containing a saturated hydrocarbon as a main component by irradiation with microwaves is provided with a reactor 11, a microwave absorber 12 which is present in the reactor 11, a supply port 13 through which the raw material is supplied into the reactor 11, and a discharge port 14 through which a decomposition product produced by allowing the raw material to pass through an absorber region at which the microwave absorber 12 is located in the reactor 11 is discharged, in which the absorber region is heated with microwaves.

Description

Decomposition device, decomposition method, and method for producing decomposed product

The present invention relates to a decomposition device for decomposing a raw material containing saturated hydrocarbons as a main component by irradiating microwaves.

In the past, naphtha was decomposed using a multi-tube method, which allows naphtha to flow through a plurality of thin reaction tubes arranged in a row, and these reaction tubes are heated from the outside by a burner, etc. Heat conduction is improved by making each reaction tube thinner so that heat can be easily transferred to the center.

[Problem to be solved by the invention] However, in the multi-tube type, the wall of each reaction tube will become high temperature, and carbon cannot be avoided from being attached to the inner wall. If coking occurs, the heat conduction will be reduced, resulting in a decrease in heating efficiency due to the decrease in heat conduction.

The present invention has been accomplished in view of this point, and its subject is to provide a novel naphtha decomposition device, decomposition method and method for producing a naphtha decomposition product which can alleviate the reduction in heating efficiency caused by coking.

Here, the so-called "naphtha" generally refers to a raw material with saturated hydrocarbons as the main component in the boiling point range of 35 to 180°C. The above-mentioned problem also exists for raw materials with saturated hydrocarbons as the main component, including ethane and heavy hydrocarbons other than naphtha.

[Technical means for solving the problem] In order to solve the above-mentioned problem, a decomposition device of one aspect of the present invention is used for decomposing a raw material with saturated hydrocarbons as a main component by microwave irradiation, and comprises: a reactor; a microwave absorber, which exists inside the reactor; a supply port, which supplies the raw material to the reactor; and a discharge port, which discharges the decomposition product generated by the raw material passing through the absorber area where the microwave absorber is located in the reactor, wherein the absorber area is heated by microwaves.

Furthermore, in one aspect of the decomposition device of the present invention, there may be further provided: a microwave generator for generating microwaves; and a waveguide for introducing the microwaves generated by the microwave generator into the reactor.

Furthermore, in a decomposition device according to one aspect of the present invention, the absorber region may be a fixed bed in which the microwave absorber is fixed.

Furthermore, in one aspect of the decomposition device of the present invention, the absorber region can be a fluidized bed in which the microwave absorber can flow.

Furthermore, in one aspect of the decomposition device of the present invention, the absorber area can be a moving bed on which the microwave absorber moves.

Furthermore, in a decomposition device of one aspect of the present invention, the microwave absorber may be in at least any one of a granular, cylindrical, cylindrical, spherical, pill-shaped, ring-shaped, shell-shaped, and honeycomb-shaped shape.

Furthermore, in a decomposition device according to one aspect of the present invention, the supply port may be located at one end of a flow path of the raw material, and the discharge port may be located at the other end of the flow path.

Furthermore, in a disassembly device according to one aspect of the present invention, when the disassembly device is set, the supply port may be located below the discharge port.

Furthermore, in a decomposition device according to one aspect of the present invention, the absorber region may be a region within the reactor ranging from a first position in the flow direction of the flow path of the raw material to a second position closer to the discharge port than the first position.

Furthermore, in one aspect of the decomposition device of the present invention, the absorber region can be configured to extend over the entire cross-section of the reactor.

Furthermore, in one aspect of the decomposition device of the present invention, there may be further provided: a first metal plate, which is arranged at a position closer to the supply port than the first position, and through which the raw material can pass; and a second metal plate, which is arranged at a position closer to the discharge port than the second position, and through which the decomposed product can pass.

Furthermore, in one aspect of the decomposition device of the present invention, there may be further provided: a laminar flow means which is arranged in the upstream region from the supply port to the first position and makes the raw material flow in a laminar flow.

Furthermore, in a decomposition device according to one aspect of the present invention, the temperature of at least a portion of the region from the second position to the discharge port of the reactor may be lower than the temperature of the absorber region during the decomposition of the raw material.

Furthermore, a decomposition method according to one embodiment of the present invention is a decomposition method for decomposing a raw material containing saturated hydrocarbons as a main component by microwave irradiation, and includes: a step of supplying the raw material to a reactor having a microwave absorber therein; a step of irradiating an absorber region in the reactor where the microwave absorber is located with microwaves to heat the absorber region; and a step of discharging a decomposition product generated by the raw material passing through the absorber region from the reactor.

Furthermore, a method for producing a decomposition product according to one aspect of the present invention is a method for producing a decomposition product by microwave irradiation, wherein the decomposition product is a decomposition product of a raw material having saturated hydrocarbons as a main component, and comprises: a step of irradiating microwaves to an absorber region where a microwave absorber in a reactor is located to heat the absorber region; and a step of producing the decomposition product by passing the raw material through the absorber region.

[Effect of the invention] According to one aspect of the present invention, in the decomposition of a raw material containing saturated hydrocarbons as the main component, microwaves are irradiated to heat the absorber region where the microwave absorber is located, and the raw material is passed through the heated absorber region, thereby alleviating the reduction in heating efficiency caused by coking.

Hereinafter, the decomposition device, decomposition method and method for producing decomposed products of the present invention are described using embodiments. In addition, in the following embodiments, the structural elements marked with the same symbols are the same or equivalent, and the re-description is sometimes omitted. The decomposition device of the present embodiment is used to decompose a raw material containing saturated hydrocarbons as a main component by microwave irradiation, and is mainly described by an example of naphtha.

FIG. 1 is a schematic diagram showing the internal structure of a decomposition device 1 according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing an example of a chemical process including the decomposition device 1. In the example of FIG. 1 , the decomposition device 1 includes: a reactor 11; a microwave absorber 12, which exists inside the reactor 11; a supply port 13, which supplies a raw material including naphtha to the reactor 11; and a discharge port 14, which discharges a decomposition product generated in an absorber region where the microwave absorber 12 is located in the reactor 11, and a microwave generator 15 for generating microwaves is connected through a waveguide 16 for introducing the microwaves generated by the microwave generator 15 into the reactor 11. The decomposition device 1 further includes a first metal plate 21 through which the raw material can pass and a second metal plate 22 through which the decomposition product can pass, and may further include a laminar flow means 25 for making the raw material a laminar flow.

The decomposition device 1 of the present embodiment can be used in a process of decomposing naphtha in a petrochemical plant to produce ethylene, etc., and can also be called a naphtha cracker. A raw material containing saturated hydrocarbons as a main component can be supplied to the reactor 11 together with, for example, diluted water vapor in a predetermined ratio.

Reactor 11 is a continuous reactor in which the raw material flows. In reactor 11, the raw material passes through the absorber area heated by the microwave introduced through waveguide 16, whereby naphtha is decomposed to generate decomposition products. The substances contained in the decomposition products are not particularly limited, but as an example, the decomposition products may include at least one of hydrogen, methane, ethylene, ethane, propylene, propane and butene, and may also include other hydrocarbons. Moreover, as an example, the decomposition products may contain ethylene, propylene and butene in total of more than 50% by weight.

Since the microwaves are introduced into the inner space of the reactor 11, the shape of the flow path of the raw material in the reactor 11, that is, the shape of the inner space of the reactor 11, is preferably a shape that can reduce the concentration of microwaves to a local part, for example, a shape without corners as much as possible. From the above viewpoint, the inner space of the reactor 11 may include, for example, a cylindrical space, a truncated cone space, or a combination thereof. In this case, the direction of the flow path of the raw material in the inner space of the reactor 11 may also be the axial direction of the cylindrical or truncated cone. When at least a portion of the internal space of the reactor 11 is cylindrical or truncated cone-shaped, the diameter of the cross section perpendicular to the axial direction of the internal space is not particularly limited, and may be, for example, in the range of 1 to 10 meters. Furthermore, when at least a portion of the internal space of the reactor 11 is cylindrical or truncated cone-shaped, the axial length of the internal space may be, for example, about 3 to 15 times the diameter of the internal space, or may be about 10 times.

In order to prevent microwaves from leaking from the internal space, the reactor 11 preferably has a wall through which microwaves do not pass. Therefore, the wall of the reactor 11 can be made of a microwave reflective material. The microwave reflective material can be, for example, metal. The metal is not particularly limited, but can be, for example, stainless steel, carbon steel, nickel, nickel alloy, copper, copper alloy, etc.

A microwave absorber 12 exists inside the reactor 11. The absorber region where the microwave absorber 12 is located is heated to a predetermined temperature by microwaves, and the raw material is decomposed by passing through the absorber region. Each component contained in the raw material supplied from the supply port 13 preferably contacts the microwave absorber 12 at least once. Therefore, the absorber region where the microwave absorber 12 is located is preferably present in a manner that covers the entire section perpendicular to the flow path of the internal space of the reactor 11 or in a manner that covers the entire surface of the section. Here, the "absorber region" includes not only the case where the microwave absorber 12 is arranged in it, such as a fixed bed described later, but also the case where the microwave absorber 12 flows or moves and can exist in it, such as a fluidized bed and a moving bed described later. Therefore, the microwave absorber 12 being located in the absorber region may refer to the microwave absorber 12 being located in a fixed position in the absorber region like a fixed bed, or it may refer to the microwave absorber 12 being located in a fluidized bed or a moving bed, and the microwave absorber 12 being able to flow or move in the absorber region.

The microwave absorber 12 may be a material that has microwave absorptivity at the frequency and temperature of the microwaves when the decomposition device 1 is in operation, that is, a material that has a high dielectric loss coefficient. Here, "dielectric loss coefficient" means the imaginary part of the complex dielectric constant. It can also be considered that a material whose temperature rises significantly when irradiated with microwaves at the frequency and temperature of the microwaves when the decomposition device 1 is in operation is a material that has microwave absorptivity. The material of the microwave absorber 12 is not particularly limited, but for example, it can be any one or more of carbon (such as graphite, carbon nanotubes and activated carbon, etc.) other than silicon carbide, magnetite and fullerene, iron, nickel, cobalt, copper, ferrite, Si ₃ N ₄ , CoO, Co ₃ O ₄ , CuO, SiC, FeO, Fe ₃ O ₄ , WC, MnO ₂ and TiO ₂ .

The shape of the microwave absorber 12 may be, for example, at least one of a granular, cylindrical, cylindrical, spherical, pill-shaped, ring-shaped, shell-shaped, and honeycomb-shaped. In this case, the raw material and the decomposed product can flow through the gaps between the microwave absorbers 12, and it is preferably a shape that can increase the surface area of the microwave absorber 12 located in the absorber region. In addition, the absorber region may be, for example, a fixed bed where the microwave absorber 12 is fixed, a fluidized bed where the microwave absorber 12 can flow, or a moving bed where the microwave absorber 12 can move.

In the case where the absorber region is a fixed bed, for example, the granular microwave absorber 12 may be microwave-transmissive and inserted into a cylindrical container through which the raw material and the decomposed product can pass, and the cylindrical container may be fixed in the reactor 11. Furthermore, for example, in the internal space of the reactor 11, the granular microwave absorber 12 may be filled between a pair of plate-like members arranged to cover a section perpendicular to the flow direction of the flow path of the raw material and the decomposed product or to cover the entire surface of the section. This plate-like member is microwave-transmissive and may have holes or pores through which the raw material and the decomposed product can pass but the granular microwave absorber 12 cannot pass. As an example, this plate-like member may be a punched plate made of a microwave-transmissive material, or may be a porous ceramic plate. Furthermore, for example, a porous plate-like member made of a material having microwave absorption properties and through which the raw material and the decomposed product can pass may be the microwave absorber 12. In this case, for example, the microwave absorber 12 may be arranged in the internal space of the reactor 11 so as to cover the cross section perpendicular to the flow path direction or to extend over the entire surface of the cross section.

As shown in Fig. 1, the absorber region where the microwave absorber 12 is located may be a region from a first position _x1 in the flow path direction of the raw material flow path, i.e., the x-axis direction, to a second position _x2 closer to the discharge port 14 than the first position _x1 . In the case where the absorber region is a fixed bed, the length ( _x2 - _x1 ) from the first position _x1 to the second position _x2 may be, for example, in the range of 10 to 100 cm, or in the range of 30 to 70 cm, or in the range of 40 to 60 cm.

The raw material is supplied to the interior of the reactor 11 from the supply port 13, and the decomposition product generated in the absorbent area is discharged from the discharge port 14. In the present embodiment, the case where the supply port 13 and the discharge port 14 are respectively connected to the internal space of the reactor 11 is mainly described. As an example, as shown in FIG1 , the supply port 13 may be located at one end of the flow path of the raw material inside the reactor 11, and the discharge port 14 may be located at the other end of the flow path. That is, the supply port 13 and the discharge port 14 may be openings arranged at both ends of the flow path direction of the reactor 11. In addition, the supply port 13 and the discharge port 14 may also be arranged at positions other than these. As an example, the supply port 13 may be located at the circumferential side surface of the upstream side of the flow path, and the discharge port 14 may be located at the circumferential side surface of the downstream side of the flow path. In addition, although FIG. 1 shows a state where the decomposition device 1 is installed and the raw material and the like flow from the supply port 13 on the lower side toward the discharge port 14 on the upper side, this is not necessarily the case. In the case where the decomposition device 1 is a fixed bed, the raw material and the like may flow from the supply port 13 on the upper side toward the discharge port 14 on the lower side, may flow in the horizontal direction, or may flow in any other direction.

As shown in FIG2 , the discharge port 14 of the decomposition device 1 can be directly or indirectly connected to a cooling tower 32 for cooling the decomposed product. As an example, the discharge port 14 can be indirectly connected to the cooling tower 32 via a gasoline tower 31 for separating heavy oil. Furthermore, the discharge port 14 can also be directly connected to the cooling tower 32. As an example, the cooling tower 32 can also be a cooling tower. In the cooling tower 32, the gasoline component can be separated, and the remaining components can be supplied to the separation step. In the separation step, hydrogen, methane, ethylene, ethane, propylene, propane, butene, etc. can be separated appropriately.

The microwave generator 15 can generate microwaves using, for example, a magnetron, a klystron, a gyrotron, or a semiconductor element. The so-called generation of microwaves using a semiconductor element means, for example, that the microwaves can be oscillated using a semiconductor element, or that the microwaves can be amplified using a semiconductor element. The frequency band of the microwaves can be, for example, around 433.92 MHz, 915 MHz, or 2.45 GHz, or can be another frequency band within the range of 300 MHz to 300 GHz.

The number of microwave generators 15 provided in the decomposition device 1 may be two as shown in Fig. 1, or may be three or more, or may be one. In the case where the decomposition device 1 has two or more microwave generators 15, each microwave generator 15 may generate microwaves of different frequencies or of the same frequency, for example.

The microwaves generated by the microwave generator 15 are introduced into the interior of the reactor 11 through the waveguide 16. The waveguide 16 may be, for example, a square waveguide or a circular waveguide. Furthermore, the waveguide 16 may be, for example, a straight waveguide, a waveguide whose waveguide path is bent at a right angle or other angles, or a waveguide whose waveguide path is bent into an arc shape. Furthermore, the waveguide 16 may be, for example, a hollow waveguide. Furthermore, the waveguide 16 may be, for example, a branching waveguide that branches the microwaves generated by the microwave generator 15 into a plurality of waveguides. A microwave-transmissive window that prevents steam, particles, etc. from moving from the interior of the reactor 11 to the microwave generator 15 side may also be provided at the end or other portion of the waveguide 16 on the reactor 11 side. This window may be made of, for example, a microwave-transmissive material. The microwave-transmissive material is not particularly limited, and may be, for example, quartz, glass, fluororesins such as polytetrafluoroethylene, ceramics, etc. Moreover, the window may be, for example, an airtight window, or may be a non-airtight window. Inside the reactor 11, as shown in FIG. 1 , microwaves may be irradiated from the upstream side of the flow path relative to the microwave absorber 12, or from the downstream side of the flow path, and may be irradiated from both the upstream side and the downstream side of the flow path simultaneously. The irradiation of the microwave absorber 12 with microwaves is usually performed in multimode.

The temperature of the absorber region can be made uniform by irradiating microwaves. In addition, the so-called uniform temperature of the absorber region can refer to, for example, that the temperature of any part included in the absorber region is included in a predetermined temperature range. This predetermined temperature range is preferably a temperature range suitable for naphtha decomposition. The absorber region can be heated to a range of 550 to 1200°C, or to a range of 600 to 700°C. In order to make the temperature of the absorber region uniform, for example, the temperature of one or more parts in the absorber region can be measured, and the microwave generator 15 can be controlled accordingly. This control can be, for example, feedback control. Through this control, for example, the output power of the microwave generator 15 can be controlled, and the phase can also be controlled. For example, the temperature of the absorber region can be uniformly maintained by controlling the phases of the plurality of microwave generators 15. The temperature of the absorber region can also be measured using, for example, a thermocouple thermometer or an infrared fiber thermometer. Furthermore, for example, in order to uniformly irradiate the absorber region with microwaves and, as a result, to make the temperature of the absorber region uniform, the shape and size of the internal space of the reactor 11, the position and angle of introduction of microwaves into the internal space, the intensity of the microwaves introduced into the internal space, etc. can be designed using simulation or the like.

The first metal plate 21 can be arranged at a position closer to the supply port 13 than the first position _x1 . And, the second metal plate 22 can be arranged at a position closer to the discharge port 14 than the second position _x2 . The first and second metal plates 21, 22 are preferably arranged to cover the entire cross section perpendicular to the flow path of the internal space of the reactor 11, or to cover the entire surface of the cross section. The first metal plate 21 and the second metal plate 22 are metal plates through which raw materials and decomposition products can pass, respectively. Therefore, the first and second metal plates 21, 22 can have a plurality of holes through which raw materials and decomposition products can pass, respectively. Examples of metals constituting the first and second metal plates 21, 22 are as described above. As an example, at least one of the first and second metal plates 21, 22 can also be a punched metal. The punched metal can be, for example, one that does not allow microwaves to pass, that is, one that reflects microwaves. The so-called not allowing microwaves to pass through can refer to, for example, greatly attenuating microwaves. The first and second metal plates 21 and 22 are perforated metals that do not allow microwaves to pass through. When microwaves are irradiated between the first and second metal plates 21 and 22, the microwaves can be confined to the area from the first metal plate 21 to the second metal plate 22, and the microwave absorber 12 can be efficiently irradiated. In this case, it is preferred to introduce the microwaves into the area from the first metal plate 21 to the second metal plate 22 inside the reactor 11 through the waveguide 16. Even if only one of the first metal plate 21 and the second metal plate 22 is used, the distribution of microwaves can still be limited to a certain area, which is beneficial.

The raw material supplied from the supply port 13 is preferably set to a laminar flow in the upstream region from the supply port 13 to the first position _x1 . By making the raw material a laminar flow, the time for the raw material to pass through the absorber region becomes uniform. Therefore, in the case where the absorber region is heated by microwaves in a manner that the temperature becomes uniform, naphtha can be heated to a uniform temperature, and ideal decomposition of naphtha can be achieved. In this case, the length of the absorber region in the flow path direction of the microwave absorber 12, that is, the thickness of the absorber region is preferably uniform.

In order to make the raw material into a laminar flow in the upstream area, a laminar flow means 25 for making the raw material into a laminar flow may also be arranged in the upstream area. The laminar flow means 25 may be, for example, one or more porous plates. The porous plate may be, for example, a porous plate-like component or a punch plate. The porous plate may be, for example, made of a microwave-reflective material or a microwave-transmissive material. The microwave-reflective material may be, for example, metal. Examples of metals are as described above. The microwave-transmissive material constituting the porous plate may be, for example, quartz, glass, ceramics, etc. In addition, the first metal plate 21 may also serve as at least one punch plate of the laminar flow means 25.

Furthermore, although FIG. 1 shows a case where the laminar flow means 25 is arranged in the upstream region, the laminar flow means 25 may not be arranged in the upstream region. That is, the decomposition device 1 may not be equipped with the laminar flow means 25. In this case, for example, the length of the flow path direction of the upstream region may be lengthened to make the raw material flow in the upstream region in a laminar flow. The length of the flow path direction of the upstream region where the laminar flow means 25 is not particularly limited, but for example, it may be 3 meters or more, 5 meters or more, or 8 meters or more.

Next, the operation of the decomposition device 1 according to one embodiment of the present invention will be described with reference to FIG1. First, a raw material including naphtha is supplied to the reactor 11 from the supply port 13 as indicated by the arrow. The supply of the raw material is usually performed continuously. That is, a predetermined amount of raw material is supplied to the reactor 11 per unit time.

Furthermore, microwaves are irradiated to the absorber region in the reactor 11 to heat it. It is preferred that the absorber region be heated to a uniform temperature by this heating. Therefore, feedback control can also be appropriately performed. The raw material supplied from the supply port 13 is made into a laminar flow by the laminar flow means 25, and passes through the heated absorber region as shown by the arrow. Since the absorber region is heated by microwaves, the naphtha contained in the raw material is heated and decomposed, and a decomposition product containing hydrocarbons with a shorter carbon length is produced.

The decomposition product generated in the absorber area is discharged from the discharge port 14 as shown by the arrow. The discharge of this decomposition product is usually also carried out continuously. That is, a predetermined amount of decomposition product is discharged from the reactor 11 per unit time. The discharged decomposition product can be supplied to the gasoline tower 31 as described above or can also be supplied to the cooling tower 32. In this way, a decomposition product obtained by decomposing a raw material containing naphtha can be produced. In addition, the temperature of the raw material after heating is determined according to the flow rate of the raw material in the reactor 11, the length of the flow path direction of the absorber area, the temperature of the absorber area, etc. Therefore, it is better to set these in a way that the raw material is heated to the desired temperature.

As described above, according to an embodiment of the present invention, in the decomposition of a raw material with saturated hydrocarbons as the main component, the absorber region where the microwave absorber 12 is located is heated by irradiating microwaves, and the raw material is passed through the heated absorber region. Even if carbon is precipitated in the microwave absorber 12 due to coking, the microwave absorption capacity of the carbon is not low and the raw material can be heated, which can alleviate the reduction in heating efficiency caused by coking.

Furthermore, according to an embodiment of the present invention, since the decomposed products generated by passing through the absorber region heated by microwaves are then rapidly cooled to the temperature of the environment that is not heated, the coking of the inner wall of the reactor 11 as in the past can be suppressed. If the inner wall is coked, the difficulty of controlling the microwaves will increase, so it is preferable to suppress the coking. If a control mechanism is provided, the control mechanism controls the temperature of the inner wall, especially the temperature of at least a portion of the inner wall between the absorber region and the discharge port 14, to a lower temperature than the absorber region, so the degree of rapid cooling can be adjusted. Furthermore, by a method other than controlling the inner wall temperature during the decomposition of the raw material, the temperature of at least a portion of the region from the second position _x2 to the outlet 14, through which the decomposed product generated by passing through the absorber region passes, can be made lower than the absorber region during the decomposition of the raw material. Specifically, the temperature of the region can be adjusted by selecting the axial length of the internal space of the reactor 11, the diameter of the internal space, the length of the flow path of the absorber region, the heat insulation of the reactor 11, etc. in the design of the reactor 11, thereby adjusting the degree of rapid cooling. Furthermore, by providing a heat recovery mechanism that recovers heat from the region from the second position _x2 to the outlet 14, the degree of rapid cooling can be adjusted.

Furthermore, according to an embodiment of the present invention, the microwave irradiation area can be limited to the first and second metal plates 21 and 22 through which the microwaves are not allowed to pass, and efficient microwave irradiation of the absorber area can be achieved.

In addition, in the decomposition device 1 of one embodiment of the present invention, as described above, the absorber region can be a fixed bed or a fluidized bed. Hereinafter, referring to FIG. 3 and FIG. 4, the case where the absorber region is a fluidized bed and the case where it is a moving bed are described respectively.

In the decomposition device 1 shown in FIG. 3 and FIG. 4 , the raw material is supplied from the supply port 13 on the lower side, and the decomposed product is discharged from the discharge port 14 on the upper side. Furthermore, the internal space of the reactor 11 shown in FIG. 3 and FIG. 4 is a combination of a cylindrical shape and a truncated cone shape. In FIG. 3 and FIG. 4 , a plurality of microwave absorbers 12 are located between the first and second metal plates 21 and 22. In this case, for example, the first position can be considered to be the position of the first metal plate 21, and the second position can be considered to be the position of the second metal plate 22. Furthermore, in order to prevent the microwave absorber 12 from falling out from between the first and second metal plates 21 and 22, the size of the hole of the first and second metal plates 21 and 22 can be made smaller than the microwave absorber 12. The shape of the microwave absorber 12 is as described above, for example, it can be at least any one of granular, cylindrical, cylindrical, spherical, pill-shaped, ring-shaped, shell-shaped and honeycomb-shaped, and can also be other shapes. In addition, in order to reduce defects or damage during the flow period or the movement period, the shape of the microwave absorber 12 is preferably granular, spherical, etc. As shown in Figures 3 and 4, in the fluidized bed and the moving bed, when the decomposition device 1 has been set, the supply port 13 can be located below the discharge port 14. That is, the raw material can flow from the supply port 13 on the lower side to the discharge port 14 on the upper side.

Since the decomposition device 1 shown in FIG. 3 is a fluidized bed, the microwave absorber 12 will flow due to the raw material supplied from the supply port 13. In addition, the raw material is preferably supplied from the supply port 13 with a flow that can make the microwave absorber 12 flow. Depending on the flow rate of the raw material in the reactor 11, the flow state of the microwave absorber 12 can be, for example, a uniform fluidized bed, a bubbling fluidized bed, or a turbulent fluidized bed. From the perspective of achieving more uniform heating of the raw material, the fluidized bed is preferably a uniform fluidized bed or a bubbling fluidized bed.

The decomposition device 1 shown in FIG. 4 is a device in which a plurality of microwave absorbers 12 are introduced from an introduction port 41 located on the downstream side of the flow path, and the introduced microwave absorbers 12 are moved to the lower side, i.e., the upstream side, by their own weight, and are accumulated on the first metal plate 21 and discharged from the discharge port 42. In addition, the discharged microwave absorbers 12 can also be introduced again from the introduction port 41. In this case, the amount of microwave absorbers 12 introduced per unit time and the amount of microwave absorbers 12 discharged per unit time are preferably equal. In the case of circulating the microwave absorbers 12, for example, coke attached to the microwave absorbers 12 discharged from the discharge port 42 can also be removed by heating or the like. Moreover, the microwave absorbers 12 after the coke has been removed can also be introduced from the introduction port 41. Furthermore, the sizes of the inlet 41 and the outlet 42 can be determined in such a way that microwaves do not leak from the inside of the reactor 11. In the example of FIG. 4 , the microwave absorber 12 is introduced from the downstream side of the flow path, but it can also be introduced from the upstream side, and it is not necessarily along the direction of the flow path, for example, it can be introduced from a direction orthogonal to the flow path.

In a fluidized bed or a moving bed, since each microwave absorber 12 flows or moves, even if coking occurs, the absorber region can be prevented from being clogged by coking. Furthermore, by achieving uniform flow or movement of the microwave absorbers 12, uniform heating of the raw materials can be achieved.

Furthermore, in one embodiment of the present invention, although the case where the absorber region exists only at one location in the flow path direction is mainly described as shown in FIGS. 1 to 3 , this is not necessarily the case. For example, as shown in FIG. 5 , the absorber region may exist at two or more locations in the flow path direction. In this case, for example, a microwave generator 15 and a waveguide 16 may be provided for each absorber region.

Furthermore, in one embodiment of the present invention, although the case where microwaves are irradiated to the absorber region from the upstream side or the downstream side is mainly described, this is not necessarily the case. For example, in the case where the absorber region of the microwave absorber 12 is provided inside the microwave-permeable reaction tube, microwaves may be irradiated to the absorber region through the circumferential side of the reaction tube. In this case, for example, one or more microwave-permeable reaction tubes are arranged inside the reactor 11, and the raw material supplied from the supply port 13 flows into each reaction tube from the first end, and the decomposition product decomposed in the absorber region of each reaction tube may also flow out from the second end of each reaction tube on the opposite side of the first end and be discharged from the discharge port 14.

Furthermore, the first metal plate 21 and the second metal plate 22 described in one embodiment of the present invention are not limited to the decomposition of raw materials with saturated hydrocarbons as the main component, but can be fully applied to gas-solid reactions in which raw materials other than these react by passing through an absorber region heated by microwaves.

Furthermore, in one embodiment of the present invention, although the decomposition device 1 is mainly described as not having the microwave generator 15 and the waveguide 16, this is not necessarily the case. The decomposition device 1 may also have the microwave generator 15 and the waveguide 16.

Furthermore, the above embodiments are examples for the specific implementation of the present invention and are not intended to limit the technical scope of the present invention. The technical scope of the present invention is not indicated by the description of the embodiments but by the scope of the patent application, and is intended to include changes within the scope of the text of the patent application and the scope of equivalent meaning.

1: Decomposition device 11: Reactor 12: Microwave absorber 13: Supply port 14: Exhaust port 15: Microwave generator 16: Waveguide 21: First metal plate 22: Second metal plate 25: Laminar flow method

FIG. 1 is a schematic diagram showing the structure of a decomposition device of an embodiment of the present invention. FIG. 2 is a schematic diagram showing an example of a chemical process including a decomposition device of the same embodiment. FIG. 3 is a schematic diagram showing the structure of a decomposition device having a fluidized bed of the same embodiment. FIG. 4 is a schematic diagram showing the structure of a decomposition device having a moving bed of the same embodiment. FIG. 5 is a schematic diagram showing an example of another structure of a decomposition device of the same embodiment.

1: Disassembly device

11: Reactor

12: Microwave absorber

13: Supply port

14: Exhaust outlet

15: Microwave generator

16: Waveguide

21: First metal plate

22: Second metal plate

25: Laminar flow method

Claims (15)

A decomposition device for decomposing a raw material containing saturated hydrocarbons as a main component by microwave irradiation, and comprising: a reactor; a microwave absorber, which exists inside the reactor; a supply port, which supplies the raw material to the reactor; and a discharge port, which discharges decomposition products generated by the raw material passing through the absorber region where the microwave absorber is located in the reactor, wherein the absorber region is heated by microwaves. The decomposition device of claim 1 further comprises: a microwave generator that generates microwaves; and a waveguide that guides the microwaves generated by the microwave generator into the reactor. A decomposition device as claimed in claim 1, wherein the absorber region is a fixed bed in which the microwave absorber is fixed. A decomposition device as claimed in claim 1, wherein the absorber region is a fluidized bed in which the microwave absorber can flow. A decomposition device as claimed in claim 1, wherein the absorber area is a moving bed on which the microwave absorber moves. A decomposition device as described in any one of claims 3 to 5, wherein the microwave absorber is at least any one of granular, cylindrical, cylindrical, spherical, pill-shaped, ring-shaped, shell-shaped and honeycomb-shaped. A decomposition device as claimed in any one of claims 3 to 5, wherein, the supply port is located at one end of the flow path of the raw material, and the discharge port is located at the other end of the flow path. A disassembly device as claimed in claim 7, wherein, when the disassembly device is in a set state, the supply port is located below the discharge port. A decomposition device as claimed in claim 1, wherein the absorber area is an area within the reactor between a first position in the flow direction of the flow path of the raw material and a second position closer to the discharge port than the first position. A decomposition device as claimed in claim 9, wherein the absorber region is configured to extend over the entire surface of the cross-section of the reactor. The decomposition device of claim 9 further comprises: a first metal plate disposed at a position closer to the supply port than the first position and through which the raw material can pass; and a second metal plate disposed at a position closer to the discharge port than the second position and through which the decomposed product can pass. The decomposition device of claim 9 further comprises: A laminar flow means, which is arranged in the upstream area from the supply port to the first position and makes the raw material into a laminar flow. A decomposition device as claimed in claim 9, wherein the temperature of at least a portion of the region of the reactor from the second position to the exhaust port is lower than the temperature of the absorber region during decomposition of the raw material. A decomposition method for decomposing a raw material containing saturated hydrocarbons as a main component by microwave irradiation, comprising: a step of supplying the raw material to a reactor having a microwave absorber therein; a step of irradiating microwaves to heat an absorber region in the reactor where the microwave absorber is located; and a step of discharging decomposition products generated by the raw material passing through the absorber region from the reactor. A method for producing a decomposition product by microwave irradiation, wherein the decomposition product is a decomposition product of a raw material with saturated hydrocarbons as a main component, comprising: a step of irradiating microwaves to heat an absorber region where a microwave absorber is located in a reactor; and a step of producing the decomposition product by passing the raw material through the absorber region.

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