Pyrolysis reactor

Abstract

A pyrolysis reactor for recovering useful products from waste is provided. A pyrolysis reactor 1 includes a rotary kiln 10 including an introduction port 17 for an object to be treated, recovery ports 18 and 19 for a useful gas, and a recovery port 20 for a useful solid, and including a cylindrical kiln shell 11 provided with heaters (gas burners 22 and 23) capable of heating an internal space, and a screw 50, and in addition, the rotary kiln 10 is provided with an inlet port 17 for the object to be treated, recovery ports 18 and 19 for the useful gas, and a recovery port 20 for the useful solid. And the screw 50 is arranged on the inner side of the cylindrical kiln shell 11.

Description

Technical Field

[0001] The present invention relates to a pyrolysis reactor suitable for recovering useful products from waste materials such as plastic waste and other waste materials. Background Art

[0002] Recycling equipment for the increasing amount of plastic waste has been proposed. As such processing equipment, equipment using a rotary kiln and other devices is known.

[0003] Patent Document 1 (PCT / TH2021 / 000065) describes an invention for a system for converting waste plastic materials into useful products. The invention involves a novel reactor that achieves efficient enhanced heating and improved product productivity, utilizing a rotating reactor, a helical ribbon screw, an upgraded heater, and other features disclosed below.

[0004] Patent Document 2 (JP-A 2008-266452) describes an invention of a pyrolysis apparatus for performing a pyrolysis step of pyrolyzing plastic waste including polyethylene to generate pyrolysis gas and a pyrolysis oil production step of generating pyrolysis oil, wherein an externally heated rotary kiln is used as a system for performing the pyrolysis step (claims).

[0005] Patent Document 3 (JP-A 2015-21024) describes the invention (claims) of a pyrolysis apparatus including a pyrolysis furnace and a rotary kiln.

[0006] Patent Document 4 (JP-A 2010-13657) describes an invention (claims) of an apparatus for catalytic cracking of waste plastics using a rotary kiln type reaction vessel.

[0007] Patent Document 5 (JP-B 3604295) describes the invention of an apparatus for treating plastic waste, which includes a screw-type dehydrochlorination apparatus, a melting tank, an absorption tower for hydrogen chloride, a pyrolysis apparatus, a recovery tower for generated oil, and a heater (claims).

[0008] The inventions of Patent Documents 1 to 5 have room for improvement because it is difficult to increase the recovery rate when recovering generated gas or useful products from waste materials such as plastic waste and other waste materials.

[0009] Patent Document 6 (JP-A 2022-45220) describes an invention (claim) of a gasification apparatus including a rotating cylindrical portion, a pyrolysis portion, and a reforming portion, and describes Figure 1 The gasification plant 1 shown in FIG. 1 is an externally heated rotary kiln (indirectly heated rotary kiln) (paragraph

[0017] ).

[0010] The gasification apparatus 1 includes a hopper 311 and a screw feeder 312 , and the screw feeder 312 is used to transfer the object to be processed fed from the hopper 311 to the inside of the gasification apparatus 1 .

[0011] This document describes that the pyrolysis section 4 of the gasification device 1 is provided on the supply port 211 side in the inner side of the rotating cylindrical section 21, and includes a partition plate 41 and a guide section 42, the partition plate 41 being a plate member parallel to and arranged on the central axis J1, and both ends of the partition plate 41 in a direction perpendicular to the central axis J1 are fixed to the inner circumferential surface of the rotating cylindrical section 21 (paragraph

[0025] ).

[0012] The inner cylinder 52 of the gasification device 1 includes an inner cylinder body 521. The inner cylinder body 521 has a cylindrical form extending along the central axis J1 and is a member that protrudes omnidirectionally in the circumferential direction from the inner peripheral surface of the rotating cylindrical portion 21 (paragraph

[0029] ). In addition, the document describes that the gasification device 1 includes a spiral plate 523 on the inside, and that the spiral plate 523 connects the outer peripheral surface of the inner cylinder shaft 522 with the inner peripheral surface of the inner cylinder body 521 and forms a spiral path 524 (paragraphs

[0030] and

[0031] ).

[0013] In other words, both ends of the partition plate 41 are fixed to the inner circumferential surface of the rotating cylindrical portion 21, the inner cylinder body 521 is a component that protrudes omnidirectionally from the inner circumferential surface of the rotating cylindrical portion 21 in the circumferential direction, and the spiral plate 523 connects the outer circumferential surface of the inner cylinder shaft 522 with the inner circumferential surface of the inner cylinder body 521, and is therefore a component that rotates integrally with the rotating cylindrical portion 21.

[0014] Patent document 7 shows a rotatable hot kiln reactor 301, in which protrusions 309 responsible for conveying and mixing the objects to be processed are provided in the inner surface ( Figure 3 ).exist Figure 3 In the apparatus shown in FIG, the interior of the hot kiln reactor 301 is divided into two zones, namely a first heating zone 302 and a second heating zone 303, by an annular baffle dam 304. In addition, a counter-rotating shaft 310 having mixing blades 311 is optionally arranged in the interior of the hot kiln reactor 301.

[0015] The inventions of Patent Documents 6 and 7 have room for improvement because it is difficult to increase the recovery rate when recovering generated gas or useful products from waste materials such as plastic waste and other waste materials.

[0016] Citation List

[0017] Patent Literature

[0018] [Patent Document 1] PCT / TH2021 / 000065

[0019] [Patent Document 2] JP-A 2008-266452

[0020] [Patent Document 3] JP-A 2015-21024

[0021] [Patent Document 4] JP-A 2010-13657

[0022] [Patent Document 5] JP-B 3604295

[0023] [Patent Document 6] JP-A 2022-45220

[0024] [Patent Document 7] US-B 10,421,911 Summary of the Invention

[0025] Problems to be solved by the device

[0026] The problem to be solved by the present device is to provide a pyrolysis reactor suitable for recovering useful products from waste materials such as plastic waste and other waste materials.

[0027] Solutions to Problems

[0028] The present device provides a pyrolysis reactor, which includes a rotary kiln and a rotary screw, wherein:

[0029] The rotary kiln consists of a rotatable cylindrical kiln shell.

[0030] The cylindrical kiln shell is equipped with an external heating heater.

[0031] A first end face of the kiln shell and a second end face of the kiln shell axially opposite to the first end face are respectively closed by a first support cover and a second support cover, the first support cover and the second support cover supporting the kiln shell and the rotating screw,

[0032] The first support cover includes an inlet for the object to be processed, and the second support cover includes a recovery port for the processed useful product. The first support cover and the second support cover are provided with at least one recovery port for the generated useful gas.

[0033] The rotary screw is arranged inside the kiln shell, and the kiln shell can rotate in the same direction as or in the opposite direction to the rotation direction of the rotary screw, and

[0034] The outer peripheral portion of the rotating screw includes spiral ribbon blades, and the inner peripheral portion of the rotating screw is of an open structure that does not include screw blades.

[0035] Effect of the device

[0036] The pyrolysis reactor of the present apparatus using a rotary kiln and a rotary screw in combination is capable of continuously recovering useful products from waste materials such as plastic waste and other waste materials, and is capable of continuously recovering useful products not only from a single type of waste material but also from a mixture of different types of waste materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a front view of a pyrolysis reactor including an axial longitudinal cross-sectional view.

[0038] Figure 2 is included Figure 1 FIG. 1 is a cross-sectional view of a portion of the first support cover 15 along the axial direction.

[0039] Figure 3 is included Figure 1 FIG. 1 is a cross-sectional view of a portion of the first support cover 15 taken in a direction orthogonal to the axial direction.

[0040] Figure 4 yes Figure 1 A perspective view of the rotating screw. DETAILED DESCRIPTION

[0041] <Pyrolysis Reactor>

[0042] refer to Figures 1 to 4 To explain the pyrolysis reactor.

[0043] exist Figure 1 In order to make the internal structure easier to understand, part of the reactor is shown in an axial longitudinal cross-sectional view (the kiln shell 11 and the furnace wall 25 are shown in a cross-sectional view, and the first support cover 15 and the second support cover 16 are shown in a front view).

[0044] Figures 1 to 3 The pyrolysis reactor 1 shown in FIG. 1 comprises a rotary kiln 10 and a rotating screw 50 .

[0045] Well-known pyrolysis reactors (see, for example, Patent Documents 2 to 4 and 6 above) can be utilized for the rotary kiln 10 .

[0046] Note that the interior of the rotary kiln 10 of the pyrolysis reactor 1 includes a single space that is not divided internally, and is not as described in the above patent document 7 (US-B 10,421,911). Figure 3 As shown in FIG, , the rotary kiln is divided into two zones. The inclusion of a single, undivided space within the rotary kiln not only facilitates the production of a highly reliable rotary kiln with a simplified structure, but also improves processing capacity because the entire interior of the rotary kiln can be utilized for the pyrolysis reaction. Furthermore, it facilitates stirring and scraping by the rotating screw, improving heat transfer performance and reliably scraping off any attached and growing coke.

[0047] Furthermore, the rotary kiln 10 of the pyrolysis reactor 1 does not include, on its inner surface, the Figure 3 As shown in FIG, protrusions 309 are responsible for conveying and mixing the objects to be processed. The lack of protrusions on the inner surface also makes it easy to produce a highly reliable rotary kiln with a simplified structure, and allows the rotary screw to be removed separately, resulting in easy maintenance. Furthermore, the rotary screw allows for easy stirring and scraping of the entire interior of the rotary kiln, resulting in improved heat transfer performance and reliable scraping of attached and grown coke.

[0048] The rotary kiln 10 is constructed of a kiln shell 11, a first support cover 15, and a second support cover 16. The kiln shell 11 can have a circular or polygonal cross section perpendicular to the central axis.

[0049] The rotary kiln 10 is placed on a support table 90 supported by a plurality of legs 95 such that the central axis of the rotary kiln 10 is horizontal or has a gradient within ±5 / 100 relative to a floor surface 100 .

[0050] Figures 1 to 4 The rotary screw 50 shown in FIG. 5 is arranged inside the rotary kiln 10 and used in combination with the rotary kiln 10 .

[0051] The rotary kiln 10 includes a cylindrical kiln shell 11 having a first end face 12a closed by a first support cover 15 and an axially opposite second end face 12b closed by a second support cover 16. The kiln shell 11 is connected to the first and second support covers 15, 16 via a rotary joint 31 having a sealing mechanism.

[0052] The kiln shell 11 and the rotating screw 50 are supported by a first support cover 15 and a second support cover 16 .

[0053] The kiln shell 11 is independently rotated by a well-known rotating device 30 .

[0054] Figures 1 to 4 The rotating screw 50 shown in FIG is independently rotated by a driving device (not shown) built into the first support cover 15 or the second support cover 16. The driving device for rotating the screw 50 can also be provided outside the first support cover 15 or the second support cover 16.

[0055] like Figure 2 As shown in FIG, the first support cover 15 includes an annular base 15a and a barrel 15b, which protrudes outward from the outer surface of the annular base 15a along the axial direction of the kiln shell 11. Although not shown in the figure, the second support cover 16 also has the same structure.

[0056] The first support cover 15 (annular base 15a) includes an introduction port 17 for the object to be processed, and the second support cover 16 (a portion corresponding to the annular base 15a) includes a recovery port 20 for the processed useful product.

[0057] Furthermore, the first support cover 15 (annular base 15 a ) includes a first recovery port 18 for the generated gas, and the second support cover 16 (a portion corresponding to the annular base 15 a ) includes a second recovery port 19 for the generated gas.

[0058] It is only necessary to provide either the first recovery port 18 or the second recovery port 19 , and if only one of them is provided, it is preferred that only the first recovery port 18 be provided.

[0059] A first recovery port 18 for the generated gas is preferably provided on the upper surface side of the first support cover 15 (annular base 15a) of the kiln shell 11, and a second recovery port 19 for the generated gas is preferably provided on the upper surface side of the second support cover 16 (the portion corresponding to the annular base 15a) of the kiln shell 11.

[0060] A recovery port 20 for the processed useful product is preferably provided on the lower surface side of the second support cover 16 (the portion corresponding to the annular base 15 a ).

[0061] The inlet 17 for the object to be processed is connected to a pipeline 17a for conveying the object to be processed, and if the object to be processed is plastic waste (molten plastic waste), it is connected to an extrusion outlet of an extruder not shown. Figure 1 and Figure 2 In the embodiment, the introduction port 17 for the object to be processed is arranged on the lower surface side of the first support cover, but does not necessarily have to be arranged on the lower surface side.

[0062] The first recovery port 18 for generated gas and the second recovery port 19 for generated gas are connected to a recovery device (not shown) for generated gas via recovery lines 18 a and 19 a , respectively.

[0063] The recovery port 20 for the treated useful product is connected to a recovery container for the useful product or the like (not shown) via a recovery line 20 a .

[0064] At the connection portion with the first support cover in the interior of the kiln shell 11, as shown Figure 2As shown in FIG, the insulating material 61 is ideally arranged to provide a surface that is inclined in an outwardly flaring manner. This inclination enables the objects to be processed introduced from the introduction port 17 to be quickly conveyed toward the rotary kiln 10 by the rotating screw 50 without flowing backward into the interior of the first support cover 15. Note that the surfaces of the insulating materials 61 and 62 are ideally lined with metal plates to protect the insulating materials. The inclination angle relative to the rotation axis of the rotary kiln 10 is preferably 10° to 45°, and more preferably 20° to 40°.

[0065] The rotary kiln 10 is an externally heated rotary kiln provided with an externally heated heater capable of heating the internal space of the kiln shell 11 .

[0066] As the external heating heater, a combustion heater using a gas burner, an electric heater using a band heater, or the like can be used.

[0067] exist Figure 1 In the embodiment, an external heating type heater using gas burners 22 and 23 is used. The external heating type heater is constructed by a furnace wall 25, gas burners 22 and 23, and exhaust ports 28 and 29 for combustion gas.

[0068] The gas burners 22 and 23 are preferably a plurality of gas burners (gas burner groups) that are opposed to the lower surface of the kiln shell 11 and arranged in a straight line along the axis of the kiln shell 11. Each of the gas burners 22 and 23 is connected to a combustible gas source and a combustion air source (not shown), and includes an ignition mechanism (not shown).

[0069] The outer surface of the kiln shell 11 includes an outer surface 11 a which is surrounded by and separated from the furnace wall 25 made of a heat-resistant and heat-insulating material, and an outer surface 11 b which is not covered with the furnace wall 25 .

[0070] like Figure 1 and Figure 3 As shown in FIG, the furnace wall 25 includes a plurality of openings 26 and 27 formed with spaces therebetween along the axis of the kiln shell 11 in a surface opposite to the bottom surface of the outer surface 11 a of the kiln shell 11 . Figure 1 Two openings are shown, but there may be one or three or more openings.

[0071] like Figure 1 and Figure 3 As shown in FIG, burners 22 and 23 as heating sources are arranged in a straight line at openings 26 and 27 of a furnace wall 25. Figure 1 In the embodiment, the burners 22 and 23 are inserted into the openings 26 and 27 respectively.

[0072] The burners 22 and 23 are arranged with a spacing d from the bottom surface of the outer surface 11 a of the kiln shell 11 .

[0073] The burner is not limited thereto, and may be of a type that blows flame horizontally between the lower surface of the kiln shell 11 and the lower surface of the furnace wall 25 from the side surface of the furnace wall 25 .

[0074] In the surface of the kiln shell 11 radially opposite to the gas burners 22 and 23, exhaust ports 28 and 29 are provided for exhausting combustion gas (carbon dioxide, steam, etc.) from the gas burners 22 and 23. The number of the exhaust ports may be one or three or more.

[0075] As the rotary screw 50, a rotary screw is used that satisfactorily has the function of kneading (mixing) the object to be processed (which can be called a stirring function), the function of promoting heat transfer between the kiln shell 11 and the object to be processed, the function of suppressing the growth of coke into the interior of the kiln shell 11, and the function of transporting the object to be processed and coke (conveying function).

[0076] exist Figure 1 and Figure 4 In the rotary screw 50, the outer periphery of the rotary screw 50 includes a spiral ribbon blade 52 surrounding a rotation axis 51, the inner periphery of the rotary screw 50 is an open structure without blades, and, further, the outer periphery of the screw includes one or more reinforcing beams 53 ( Figure 1 The rotating shaft 51 and the belt blades 52 are connected to each other via a plurality of support rods or the like.

[0077] The width of the belt blade 52 is preferably 5% to 20% of the inner diameter of the kiln shell 11, and more preferably 5% to 10%, the thickness of the belt blade 52 is preferably 5 mm to 20 mm, the pitch is preferably 20% to 100% of the inner diameter of the kiln shell 11, and more preferably 20% to 50%, the diameter of the rotating shaft 51 is preferably 10% to 40% of the inner diameter of the kiln shell 11, and more preferably 10% to 30%, and the interval between the outer edge of the belt blade 52 and the inner surface of the kiln shell 11 is preferably 5 mm to 30 mm.

[0078] Figure 1 and Figure 4 The belt blade 52 shown in the figure has the form of a continuous belt with a pitch angle that is fixed from the beginning to the end, but this can be replaced by a belt form in which the outer periphery of the belt is partially cut, a belt form with a partially varying pitch angle, or a combination of these belt forms.

[0079] Providing the spiral ribbon blade 52 only in the outer peripheral portion ensures a sufficient opening area in the inner side thereof so that the flow of gas generated from the object to be processed toward the first recovery port 18 or the second recovery port 19 for the generated gas is not blocked.

[0080] In addition, part of the object to be processed can pass over the spiral ribbon blades and return to the upstream side, so that the object to be processed stays inside the reactor for a longer time, and at the same time, the stirring action associated with the large movement of the object to be processed at this time promotes heat transfer between the kiln shell 11 and the object to be processed.

[0081] One or more reinforcing beams 53 parallel to the rotating axis 51 of the screw improve the rigidity of the screw 50 and significantly reduce bending of the screw 50 due to the weight of the screw 50 itself, so that even an axially long reactor requires only two support mechanisms for the screw 50, namely the first support cover 15 and the second support cover 16, and does not require a support mechanism for the screw 50 that is difficult to implement inside the kiln shell 11.

[0082] Furthermore, when one or more reinforcing beams 53, which are parallel to the screw's rotational axis 51, are positioned close to the inner surface 11c of the kiln shell 11, the stirring action caused by the substantial movement of the portion of the object being processed scraped by the reinforcing beams 53 promotes heat transfer between the kiln shell 11 and the object being processed. Furthermore, the effect of suppressing the growth of coke into the interior of the kiln shell 11 is also significantly enhanced.

[0083] The cross-sectional shape of the reinforcement beam 53 can be circular, rectangular, triangular, trapezoidal, or a combination thereof. Using a cross-sectional shape that is wedge-shaped along the screw's rotational direction (e.g., triangular or trapezoidal) allows the reinforcement beam 53 to more effectively scrape the object to be processed, promote stirring, improve heat transfer between the kiln shell 11 and the object to be processed, and improve the effect of suppressing coke growth into the kiln shell 11.

[0084] When the reinforcing beam 53 has a trapezoidal cross-sectional shape and is a shape having a pair of side surfaces and a bottom surface therebetween, the angle formed by each side surface and the bottom surface is an acute angle. This is preferable because it enables the reinforcing beam 53 to more effectively scrape the objects to be processed, promote stirring, improve heat transfer between the kiln shell 11 and the objects to be processed, and improve the effect of suppressing coke growth inside the kiln shell 11, regardless of whether the kiln shell 11 is rotated forward or backward (in the reverse direction) relative to the screw 50. Instead of a trapezoidal cross-sectional shape in which each side surface forms an acute angle with the bottom surface, the reinforcing beam 53 may have a cross-sectional shape in which only one of the side surfaces forms an acute angle with the bottom surface.

[0085] Note that the rotary screw 50 is not limited to Figure 1 and Figure 3As the rotary screw 50, not only the screw belt shown in JP-A 2007-307549 or the screw belt shown in JP-A 2004-41858 can be used. Figure 4 In addition to the screw shown in the , which is provided with screw blades 38b, a double-blade screw, a screw with a paddle, a cut flight screw, a ribbon screw (paragraph

[0067] of the same publication), etc. can also be used. Furthermore, if a reinforcing beam having a wedge-shaped cross-sectional shape or another cross-sectional shape is used, the rotating screw is not limited to a spiral ribbon blade. Even if the rotating screw has another form, the rotating screw can include one or more reinforcing beams extending through its outer periphery and parallel to the rotation axis of the rotating screw.

[0086] The rotation speed of the kiln shell 11 and the rotating screw 50 is preferably adjustable within the range of 0 to 10 r / min.

[0087] The rotation speeds of the kiln shell 11 and the rotary screw 50 may be adjusted depending on factors such as the object to be processed, the processing amount, and other factors, and a form in which both of them are rotated and a form in which one of them is rotated can be implemented in combination.

[0088] The kiln shell 11 and the rotary screw 50 of the rotary kiln 10 can be operated in any of the following rotation states:

[0089] A first form, in which the kiln shell 11 is rotated forward and the rotary screw 50 is rotated forward;

[0090] A second form in which the kiln shell 11 is rotated backward (reversely) and the rotary screw 50 is rotated forward;

[0091] A third form in which the kiln shell 11 is rotated forward, and the rotary screw 50 is rotated backward (reversely); and

[0092] A fourth form in which the kiln shell 11 is rotated backward (reversely), and the rotary screw 50 is rotated backward (reversely).

[0093] The pyrolysis reactor 1 can be used to recover gaseous useful products and solid useful products from plastic waste.

[0094] It is capable of processing not only the same type of plastic waste, but also a mixture of different types of plastic waste.

[0095] <Method for Operating a Pyrolysis Reactor>

[0096] Hereinafter, a method for operating a pyrolysis reactor is explained taking the case of processing plastic waste as an example.

[0097] The method includes the step of preliminarily heating the kiln shell 11 with external heating heaters (gas burners 22 and 23), wherein the heating temperature of the external heating heaters (gas burners 22 and 23) is a temperature at which the temperature of the internal space of the heated kiln shell 11 reaches a temperature equal to or greater than the melting point of the waste to be processed (for example, plastic waste or another waste material capable of melting such as rubber waste).

[0098] When the waste to be treated is a mixture of different types of plastic waste, the temperature to be reached is equal to or greater than the highest melting point of the plastic waste.

[0099] When the gas burners 22 and 23 are operated, their flames heat the lower portion of the outer surface 11a of the kiln shell linearly and almost uniformly along the axis of the kiln shell 11. Even if heating is performed by a method in which only the lower surface of the outer surface 11a of the kiln shell is heated as described above, rather than by a method in which the circumference of the outer surface 11a of the kiln shell is uniformly heated, it is unlikely to cause a large temperature difference in the circumferential direction of the kiln shell 11 because the portion to be heated continuously moves in the circumferential direction as the kiln shell 11 rotates. A large temperature difference in the circumferential direction is harmful because it carries the risk of causing bow deformation of the kiln shell 11 due to thermal expansion differences, but such a problem is unlikely to occur.

[0100] In the next step, waste or waste in a molten state is introduced from the introduction port 17 for the object to be processed into the kiln shell 11. When the waste is plastic waste, the plastic waste can be in a molten state, but does not necessarily have to be in a molten state.

[0101] In the next step, as the cylindrical kiln shell 11 and the rotating screw 50 are rotated, generated gas and useful products are generated through a pyrolysis reaction.

[0102] In this step, the rotation directions of the kiln shell 11 and the rotating screw 50 can be selected from the first to fourth forms, and the rotation speeds of the kiln shell 11 and the rotating screw 50 can also be adjusted.

[0103] In the next step, the generated gas is recovered from the first recovery port 18 and the second recovery port 19 for the generated gas, and the treated useful product is recovered from the recovery port 20 for the useful product.

[0104] When the object to be processed is waste in a molten state, naphtha or the like is recovered as generated gas from the first recovery port 18 and the second recovery port 19 for generated gas. In addition, solid residues such as carbon black or the like are recovered from the recovery port 20 for useful products.

[0105] The above steps can be linked to each other and performed in succession to recover the generated gas and useful products.

[0106] The operation methods in the following forms 1a to 4a can be performed, wherein the operations are performed in the first to fourth forms and at this time the rotation speed (rotation rate) of the kiln shell 11 and the rotation speed (rotation rate) of the rotary screw 50 are appropriately changed and combined.

[0107] (Operation form 1a)

[0108] Operation form 1a, in which the kiln shell 11 is rotated forward and the rotary screw 50 is rotated forward. In operation form 1a, the kiln shell 11 and the rotary screw 50 can be rotated at the same speed or at different speeds, or the rotation of the kiln shell 11 or the rotary screw 50 can be stopped in other ways.

[0109] (Operation form 2a)

[0110] Operation form 2a, in which the kiln shell 11 is rotated backward (reversely), and the rotating screw 50 is rotated forward. In operation form 2a, the kiln shell 11 and the rotating screw 50 can be rotated at the same speed or at different speeds, or the rotation of the kiln shell 11 or the rotating screw 50 can be stopped in other ways.

[0111] (Operation form 3a)

[0112] Operation form 3a, in which the kiln shell 11 is rotated forward and the rotating screw 50 is rotated backward (reversely). In operation form 3a, the kiln shell 11 and the rotating screw 50 can be rotated at the same speed or at different speeds, or the rotation of the kiln shell 11 or the rotating screw 50 can be stopped in other ways.

[0113] (Operation form 4a)

[0114] Operation form 4a, in which the kiln shell 11 is rotated backward (reversely), and the rotating screw 50 is rotated backward (reversely). In operation form 4a, the kiln shell 11 and the rotating screw 50 can be rotated at the same speed or at different speeds, or the rotation of the kiln shell 11 or the rotating screw 50 can be stopped in other ways.

[0115] The method for operating a pyrolysis reactor can be performed by a method in which any one of the operating methods in operating forms 1a to 4a is selected and performed, or a method in which one of a plurality of operating methods selected from the operating methods in operating forms 1a to 4a is performed and then switched to another operating method during operation.

[0116] The rotation speed of the kiln shell 11 is preferably 0.5 to 10 r / min, more preferably 1 to 8 r / min, and further preferably 2 to 6 r / min.

[0117] The rotation speed of the rotary screw 50 is preferably 0.1 to 10 r / min, more preferably 0.1 to 8 r / min, and further preferably 0.1 to 6 r / min.

[0118] The operating methods in forms 1a and 2a are general operating methods, whereby the waste to be processed (for example, plastic waste or another waste material capable of melting such as rubber waste) is thermally decomposed during the process of being transferred from the first support cover 15 side to the second support cover 16 side, useful gas is recovered from the first recovery port 18 and the second recovery port 19 for the generated gas, and useful products are recovered from the recovery port 20 for useful products.

[0119] If the operation forms selected from the operation forms 1a, 2a, 3a and 4a are combined, it is possible to adjust one, two or three selected from the following: the heating state of the objects to be processed in the kiln shell 11; the mixing state or the conveying state of the objects to be processed in the kiln shell 11; and the residence time of the objects to be processed in the kiln shell 11.

[0120] Therefore, not only can an increased recovery rate of the produced gas or useful product be achieved, but also improved energy efficiency during operation can be expected.

[0121] Industrial Applicability

[0122] The pyrolysis reactor of the present apparatus can be utilized as a device for recovering generated gas or useful products from waste materials including plastic waste (for example, other waste materials such as rubber waste that can be melted in addition to plastic waste).

[0123] Description of Reference Numbers

[0124] 1 Pyrolysis reactor

[0125] 10 Rotary kiln

[0126] 11 kiln shell

[0127] 17Inlet for the object to be processed

[0128] 18 First recovery port for generated gas

[0129] 19 Second recovery port for generated gas

[0130] 20 Recovery port for processed useful products

[0131] 22, 23 Gas burner

[0132] 25 furnace wall

[0133] 31 Rotary joint with sealing mechanism

[0134] 50 rotating screw

[0135] 51 Rotation axis

[0136] 52 spiral ribbon blades

[0137] 53 Strengthening beam.

Claims

1. A pyrolysis reactor comprising a rotary kiln and a rotary screw, wherein: The rotary kiln comprises a rotatable cylindrical kiln shell. The cylindrical kiln shell is provided with an external heating heater. A first end face of the kiln shell and a second end face of the kiln shell axially opposite to the first end face are respectively closed by a first support cover and a second support cover, the first support cover and the second support cover supporting the kiln shell and the rotating screw, The first support cover includes an inlet for the object to be processed, and the second support cover includes a recovery port for the processed useful product. The first support cover and the second support cover are provided with at least one recovery port for the generated useful gas. The rotary screw is arranged inside the kiln shell, and the kiln shell can rotate in the same direction as or in the opposite direction to the rotation direction of the rotary screw, and, The outer periphery of the rotary screw includes spiral ribbon blades, and the inner periphery of the rotary screw is of an open structure that does not include screw blades.

2. The pyrolysis reactor according to claim 1, wherein The rotating screw includes one or more reinforcing beams extending through the helical ribbon blades and parallel to the axis of rotation of the rotating screw.

3. The pyrolysis reactor according to claim 1, wherein At a connection portion with the first supporting cover in the interior of the kiln shell, a heat insulating material is provided to provide a surface inclined in an outwardly flared manner, and the surface of the heat insulating material is lined with a metal plate to protect the heat insulating material.

4. The pyrolysis reactor according to claim 1, wherein The external heating heater is a furnace that surrounds the outer surface of the kiln shell with a gap therebetween. A burner as a heating source is arranged in a straight line at a lower portion of the furnace to oppose the lower surface of the kiln shell, or is arranged to blow flames horizontally between the lower surface of the kiln shell and the lower surface of the furnace wall from a side surface of the furnace, and, An exhaust port of the burner for combustion gas is arranged at an upper portion of the furnace.

5. The pyrolysis reactor according to claim 1, wherein The kiln shell and the rotary screw are each rotated by a rotating device disposed outside the kiln shell, and the rotation speed of the kiln shell can be adjusted within a range of 0 to 10 r / min.

6. The pyrolysis reactor according to claim 1, wherein The cylindrical kiln shell includes an undivided single space inside and does not include a protrusion protruding from an inner wall surface.

7. The pyrolysis reactor according to claim 1, wherein The recovery port for the generated useful gas is provided at one or more positions on the upper surface side of the first support cover or the upper surface side of the second support cover of the kiln shell, and, The recovery port for the processed useful product is provided on the lower surface side of the second support cover.

8. The pyrolysis reactor according to claim 1, wherein The kiln shell is arranged so that a center line of the kiln shell is horizontal or has a gradient within ±5 / 100 relative to a horizontal surface.

9. The pyrolysis reactor according to claim 1, wherein The reactor may be operated in any of the following configurations: A first form, wherein the kiln shell is rotated forward and the rotary screw is rotated forward; A second form, wherein the kiln shell is rotated backward, that is, in the reverse direction, and the rotary screw is rotated forward; A third form, wherein the kiln shell is rotated forward, and the rotary screw is rotated backward, that is, rotated in the opposite direction; and A fourth form, wherein the kiln shell is rotated backward, that is, rotated in the opposite direction, and the rotary screw is rotated backward, that is, rotated in the opposite direction, and, Furthermore, in each of the first to fourth forms, the rotation speeds of the kiln shell and the rotating screw are adjustable.

10. The pyrolysis reactor according to claim 1, wherein The reactor is used for recovering gaseous useful products and solid useful products from plastic waste.

11. The pyrolysis reactor according to claim 1, wherein The reactor is used to recover gaseous useful products and solid useful products from a mixture of different types of plastic waste.

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