Waste plastic treatment equipment using microwaves, and waste plastic pyrolysis apparatus for same

Abstract

According to the present invention, waste plastic treatment equipment is provided, the equipment comprising: a waste plastic pyrolysis apparatus, which pyrolyzes waste plastic using microwaves as an energy source so as to generate pyrolysis gas; a pipe structure for providing a pipe passage through which the pyrolysis gas is discharged and flows from the waste plastic pyrolysis apparatus; a gas condensing means, which condenses the pyrolysis gas so as to generate pyrolysis oil; and a pyrolysis oil storage part for storing the pyrolysis oil, wherein the waste plastic pyrolysis apparatus includes: a pyrolysis furnace for providing an accommodation space in which waste plastic to be pyrolyzed is accommodated; a microwave supply unit for generating microwaves and supplying same to the accommodation space; and a heating element which absorbs the microwaves so as to generate heat, the heating element having a plate shape and being horizontally disposed in the accommodation space, the waste plastic to be pyrolyzed is placed on the heating element so as to be in direct contact therewith, and the microwaves are emitted in the downward direction through an emission hole disposed above and facing the heating element, so as to pass through the waste plastic to be pyrolyzed in the accommodation space and be absorbed into the heating element.

Description

Microwave-based waste plastic processing equipment and waste plastic pyrolysis device therefor

[0001] The present invention relates to a technology for processing waste plastic, and more specifically, to equipment for producing pyrolysis oil by pyrolyzing waste plastic.

[0002] Pyrolysis oil is oil recovered in a liquid state by decomposing waste plastic at high temperatures, and has recently been receiving significant attention in the waste plastic recycling industry.

[0003] Equipment producing pyrolysis oil essentially includes a pyrolysis device that heats and decomposes waste plastic. Patent No. 10-1729859 describes a system that utilizes the thermal power of a combustion burner as a heat source for the pyrolysis of waste plastic. However, using this combustion burner as a heat source for pyrolysis limits the improvement in thermal efficiency and also raises the issue of harmful gases generated by combustion.

[0004] The purpose of the present invention is to provide waste plastic processing equipment capable of efficiently and environmentally decomposing waste plastic to produce pyrolysis oil, and a waste plastic pyrolysis device for the same.

[0005] In order to achieve the above object of the present invention, according to one aspect of the present invention, there is provided a waste plastic processing device comprising: a waste plastic pyrolysis device that uses microwaves as an energy source to pyrolyze waste plastic to generate pyrolysis gas; a pipe structure that provides a pipe passage through which the pyrolysis gas is discharged from the waste plastic pyrolysis device and flows; a gas condensation means that condenses the pyrolysis gas to generate pyrolysis oil; and a pyrolysis oil storage unit that stores the pyrolysis oil, wherein the waste plastic pyrolysis device comprises a pyrolysis furnace that provides a receiving space in which waste plastic to be pyrolyzed is received therein, a microwave supply unit that generates microwaves and supplies them to the receiving space, and a heating element that absorbs microwaves and generates heat, wherein the heating element is in the shape of a plate and is horizontally arranged in the receiving space, and the waste plastic to be pyrolyzed is placed on the heating element so as to be in direct contact with it, and wherein microwaves in the receiving space are radiated downward through a radiation port that is oppositely arranged on the heating element so as to penetrate the waste plastic to be pyrolyzed and be absorbed by the heating element.

[0006] In order to achieve the above object of the present invention, according to another aspect of the present invention, there is provided a waste plastic processing equipment comprising: a waste plastic pyrolysis device that pyrolyzes waste plastic using microwaves as an energy source to generate pyrolysis gas; a pipe structure that provides a pipe passage through which the pyrolysis gas is discharged from the waste plastic pyrolysis device and flows; a gas condensation means that condenses the pyrolysis gas to generate pyrolysis oil; and a pyrolysis oil storage unit that stores the pyrolysis oil, wherein the waste plastic pyrolysis device comprises a pyrolysis furnace that provides a receiving space in which waste plastic to be pyrolyzed is received therein, a microwave supply that generates microwaves and supplies them to the receiving space, and a heating element that absorbs microwaves and generates heat, and the gas condensation means is installed in at least a portion of the piping passage, so that pyrolysis oil is generated in the process in which the pyrolysis gas flows through the piping passage, and the gas condensation means has a gas condensation tube through which a cooling fluid flows.

[0007] In order to achieve the above object of the present invention, according to another aspect of the present invention, there is provided a waste plastic treatment device comprising: a waste plastic pyrolysis device that uses microwaves as an energy source to pyrolyze waste plastic to generate pyrolysis gas; a pipe structure that provides a pipe passage through which the pyrolysis gas is discharged from the waste plastic pyrolysis device and flows; a gas condensation means that condenses the pyrolysis gas to generate pyrolysis oil; and a pyrolysis oil storage unit that stores the pyrolysis oil, wherein the waste plastic pyrolysis device comprises a pyrolysis furnace that provides a receiving space in which waste plastic to be pyrolyzed is received therein, a microwave supply that generates microwaves and supplies them to the receiving space, and a heating element that absorbs microwaves and generates heat, the heating element being disposed below the waste plastic to be pyrolyzed in the receiving space, and microwaves in the receiving space are absorbed by the heating element by penetrating the waste plastic to be pyrolyzed, and the gas condensation means being installed in at least a portion of the pipe passage, so that pyrolysis oil is generated in a process in which the pyrolysis gas flows through the pipe passage.

[0008] In order to achieve the above object of the present invention, according to another aspect of the present invention, a waste plastic pyrolysis device is provided, comprising: a pyrolysis furnace providing a receiving space in which waste plastic to be pyrolyzed is received; a microwave supply device generating microwaves and supplying them to the receiving space; and a heating element disposed below the waste plastic in the pyrolysis furnace, so as to be in direct contact with the waste plastic, and absorbing the supplied microwaves to pyrolyze the waste plastic.

[0009] The present invention achieves all of the aforementioned objectives. Specifically, by utilizing the heat generated from a heating element that absorbs microwaves and generates heat, waste plastic is thermally decomposed, thereby improving energy efficiency and eliminating the generation of harmful gases during combustion.

[0010] In addition, since the gas condensation means for condensing pyrolysis gas to produce pyrolysis oil is installed within the pipe through which the pyrolysis gas flows, a separate condensing device is not required, and the size of the entire equipment can be reduced.

[0011] And, by using a vacuum pump that creates a vacuum state inside the pyrolysis furnace and a nitrogen purge device that purges nitrogen gas into the inside of the pyrolysis furnace, the amount of oxygen inside the pyrolysis furnace can be significantly reduced before the pyrolysis reaction is performed, thereby preventing the occurrence of safety accidents such as fire.

[0012] FIG. 1 is a drawing schematically illustrating the configuration of waste plastic processing equipment according to one embodiment of the present invention.

[0013] Figure 2 is a drawing showing the configuration of a waste plastic pyrolysis device equipped in the waste plastic processing equipment illustrated in Figure 1.

[0014] Figure 3 is a drawing showing a gas condenser equipped in the waste plastic processing equipment illustrated in Figure 1.

[0015] FIG. 4 is a drawing showing another embodiment of the gas condenser illustrated in FIG. 3.

[0016] Hereinafter, the configuration and operation of an embodiment of the present invention will be described in detail with reference to the drawings.

[0017] FIG. 1 schematically illustrates the configuration of waste plastic processing equipment according to one embodiment of the present invention. Referring to FIG. 1, waste plastic processing equipment (100) according to one embodiment of the present invention includes a waste plastic pyrolysis device (110) that pyrolyzes waste plastic to generate gas, a pyrolysis oil storage unit (150) that stores pyrolysis oil produced by condensing gas generated from the waste plastic pyrolysis device (110), a pipe structure (160) through which gas discharged from the waste plastic pyrolysis device (110) flows, and a filter (198) that filters out harmful substances from the gas generated from the waste plastic pyrolysis device (110). The waste plastic processing equipment (100) pyrolyzes waste plastic using microwaves as an energy source to generate gas, and condenses the gas generated by the pyrolysis of waste plastic to produce pyrolysis oil, which is a liquid oil. In this embodiment, the waste plastics to be pyrolyzed include various resin materials such as polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC). In this embodiment, the waste plastics to be pyrolyzed may be in various forms such as powder, bulk, pieces, and lumps.

[0018] A waste plastic pyrolysis device (110) generates gas by pyrolyzing waste plastic using microwaves as an energy source. The waste plastic pyrolysis device (110) comprises a pyrolysis furnace (120), a microwave supply device (130) that supplies microwaves to the pyrolysis furnace (120), a heating element (140) that receives microwaves and generates heat, a vacuum pump (145) that removes oxygen from the pyrolysis furnace (120), and a nitrogen purge device (148) that performs nitrogen purging on the pyrolysis furnace (120).

[0019] Referring to FIGS. 1 and 2, a pyrolysis furnace (120) provides a receiving space (124) in which waste plastic (P) to be pyrolyzed is received. A heating element (140) heated by microwaves is installed in the receiving space (124) of the pyrolysis furnace (120). A microwave supply (130), a vacuum pump (145), and a nitrogen purge mechanism (148) are installed outside the pyrolysis furnace (120). An exhaust port (126) through which gas in the receiving space (124) is discharged is formed in the pyrolysis furnace (120). Waste plastic (P) is pyrolyzed in the receiving space (124) of the pyrolysis furnace (120) to generate gas. Hereinafter, the gas generated by pyrolyzing waste plastic is referred to as 'pyrolysis gas'. The pyrolysis gas in the receiving space (124) is discharged from the receiving space (124) through the exhaust port (126). The pyrolysis gas discharged from the receiving space (124) through the exhaust port (126) is condensed to form pyrolysis oil.

[0020] A microwave supply (130) supplies microwaves to the receiving space (124) of the pyrolysis furnace (120). The microwave supply (130) includes a magnetron (132) that generates microwaves, and a waveguide (135) that transmits microwaves generated from the magnetron (132) to the receiving space (124) of the pyrolysis furnace (120). In the present embodiment, the microwave supply (130) is described as being installed at the top of the pyrolysis furnace (120) so as to be positioned above the receiving space (124) formed in the pyrolysis furnace (120). In the present embodiment, the microwave supply (130) is described as being provided in multiple numbers as illustrated, but alternatively, there may be only one, which also falls within the scope of the present invention.

[0021] The magnetron (132) generates microwaves. Since the magnetron (132) includes a configuration of a conventional magnetron that generates microwaves, a detailed description of the magnetron (132) is omitted here. Microwaves generated in the magnetron (132) are transmitted to the receiving space (124) of the pyrolysis furnace (120) through the waveguide (135).

[0022] The waveguide (135) transmits microwaves generated from the magnetron (132) to the receiving space (124) of the pyrolysis furnace (120). The microwaves transmitted through the waveguide (135) are radiated downward from the receiving space (124) through a microwave radiator (136) formed at the end of the waveguide (135) and formed on the ceiling of the receiving space (124). Since the waveguide (135) includes a configuration of a typical waveguide, a detailed description of the waveguide (135) is omitted here.

[0023] The heating element (140) absorbs microwaves radiated into the receiving space (124) of the pyrolysis furnace (120) by a plurality of microwave suppliers (130) and generates heat. The heating element (140) is plate-shaped and is generally horizontally arranged at the lower portion of the receiving space (124) facing the microwave radiator (136). In the present embodiment, the heating element (140) is described as a SiC heating element having silicon carbide (SiC) as its main component. Waste plastic (P), which is a target of pyrolysis, is placed on the heating element (140). The waste plastic (P) is in direct contact with the heating element (140). Microwaves radiated downward from the ceiling of the receiving space (124) through the microwave radiator (136) are transmitted to the heating element (140) by passing through the electrically non-conductive waste plastic (P). Heat is generated in the heating element (140) by microwaves, and waste plastic (P) is thermally decomposed by the heat generated in the heating element (140).

[0024] In this embodiment, the heating element (140) is described as being installed fixedly in the receiving space (124) of the pyrolysis furnace (120), but the present invention is not limited thereto. The heating element may also be used movably by being installed on the floor of a cart that can load waste plastic to be pyrolyzed and enter and exit the pyrolysis furnace (120).

[0025] Additionally, waste plastics subject to pyrolysis may be continuously supplied to the pyrolysis furnace (120) by a moving means such as a conveyor belt. In this case, a heating element may be attached to the outer surface of the conveyor belt or a material forming a heating element may be coated thereon.

[0026] A vacuum pump (145) removes oxygen by exhausting air from the receiving space (124) of the pyrolysis furnace (120). The vacuum pump (145) operates before microwaves are irradiated into the receiving space (124), thereby significantly reducing the amount of oxygen within the receiving space (124). Accordingly, the risk of fire due to the high-temperature environment of pyrolysis is reduced.

[0027] The nitrogen purge mechanism (148) purges nitrogen gas into the receiving space (124) of the pyrolysis furnace (120). The nitrogen purge mechanism (148) operates after the air in the receiving space (124) is exhausted by the vacuum pump (145) and before microwaves are irradiated into the receiving space (124), thereby further reducing the amount of oxygen in the receiving space (124). Accordingly, the risk of fire due to the high-temperature environment of pyrolysis is reduced. The nitrogen purge mechanism (148) may also purge nitrogen gas into the receiving space (124) to cool the pyrolysis furnace (120) after the pyrolysis process of the waste plastic (P) is completed.

[0028] Referring to Fig. 1, the pyrolysis oil storage unit (150) stores pyrolysis oil produced by condensing pyrolysis gas generated from a waste plastic pyrolysis device (110). The pyrolysis oil storage unit (150) is provided with a first pyrolysis oil storage tank (152) and a second pyrolysis oil storage tank (156) in which pyrolysis oil is stored and which are arranged sequentially along the direction in which pyrolysis gas discharged from a pyrolysis furnace (120) flows.

[0029] The first pyrolysis oil storage tank (152) provides a first storage space in which pyrolysis oil is stored. A first inlet (153) and a first outlet (154) are formed at the top of the first pyrolysis oil storage tank (152). Through the first inlet (153), pyrolysis gas flows into the first storage space of the first pyrolysis oil storage tank (152), and through the first outlet (154), pyrolysis gas is discharged from the first storage space of the first pyrolysis oil storage tank (152). Additionally, pyrolysis oil flows into the first storage space of the first pyrolysis oil storage tank (152) through the first inlet (153) and the first outlet (154).

[0030] The second pyrolysis oil storage tank (156) is an additional pyrolysis oil storage tank, and provides a second storage space, which is an additional storage space in which pyrolysis oil is stored. A second inlet (157) and a second outlet (158) are formed at the top of the second pyrolysis oil storage tank (156). Through the second inlet (157), pyrolysis gas flows into the second storage space of the second pyrolysis oil storage tank (156), and through the second outlet (158), pyrolysis gas is discharged from the second storage space of the second pyrolysis oil storage tank (156). Additionally, pyrolysis oil flows into the second storage space of the second pyrolysis oil storage tank (156) through the second inlet (157) and the second outlet (158).

[0031] In this embodiment, the pyrolysis oil storage unit (150) is described as having two pyrolysis oil storage tanks (152, 156), but alternatively, it may have one pyrolysis oil storage tank or three or more pyrolysis oil storage tanks, which also fall within the scope of the present invention.

[0032] A piping structure (160) provides a piping passage through which pyrolysis gas discharged from a waste plastic pyrolysis device (110) flows. The piping structure (160) includes an introduction piping section (170), an intermediate piping section (180), and an exhaust piping section (190) arranged sequentially along the flow direction of pyrolysis gas discharged from a receiving space (124) of a pyrolysis furnace (120).

[0033] The introduction pipe (170) extends between the pyrolysis furnace (120) and the first pyrolysis oil storage tank (152), and connects the exhaust port (126) formed in the pyrolysis furnace (120) with the first inlet port (153) formed in the first pyrolysis oil storage tank (152). The pyrolysis gas in the receiving space (124) formed in the pyrolysis furnace (120) flows along the introduction pipe (170) and flows into the first pyrolysis oil storage tank (152). The introduction pipe section (170) includes an introduction upstream pipe (171) extending upward from the pyrolysis furnace (120), an introduction downstream pipe (173) extending upward from the first pyrolysis oil storage tank (152), an introduction extension pipe (175) extending between the introduction upstream pipe (171) and the introduction downstream pipe (173), an introduction upstream connection pipe (178) connecting the introduction extension pipe (175) and the introduction upstream pipe (171), and an introduction downstream connection pipe (179) connecting the introduction extension pipe (175) and the introduction downstream pipe (173). The pyrolysis gas discharged from the pyrolysis furnace (120) flows sequentially along the introduction upstream pipe (171), the introduction upstream connection pipe (178), the introduction extension pipe (175), the introduction downstream connection pipe (179), and the introduction downstream pipe (173) and is introduced into the first pyrolysis storage tank (152).

[0034] The upstream pipe (171) of the introduction section extends upward from the pyrolysis furnace (120). The lower end, which is the upstream end of the upstream pipe (171), is connected to an exhaust port (126) formed in the pyrolysis furnace (120), and the upper end, which is the downstream end of the upstream pipe (171), is connected to an upstream connection pipe (178) of the introduction section.

[0035] The introduction downstream pipe (173) extends upward from the first pyrolysis oil storage tank (152). The lower end, which is the downstream end of the introduction downstream pipe (173), is connected to the first inlet (153) formed in the first pyrolysis oil storage tank (152), and the upper end, which is the upstream end of the introduction downstream pipe (173), is connected to the introduction downstream connection pipe (179).

[0036] Fig. 3 is a longitudinal cross-sectional view of the downstream pipe (173) of the introduction section, and Fig. 3 illustrates the inside of the downstream pipe (173) of the introduction section. Referring to Fig. 3, a gas condensation pipe (174) is installed inside the downstream pipe (173) of the introduction section. A cooling fluid (W), such as cooling water, flows through the gas condensation pipe (174). The gas condensation pipe (174) is coiled and extended along the length of the downstream pipe (173) of the introduction section. This shape increases the contact area between the pyrolysis gas flowing along the downstream pipe (173) of the introduction section and the gas condensation pipe (174). At least a portion of the pyrolysis gas flowing through the downstream pipe (173) of the introduction section is condensed by the cooling fluid (W) flowing through the condensation pipe (174) to form pyrolysis oil. The pyrolysis oil produced in the downstream pipe (173) of the introduction section falls due to its own weight and flows into the first storage space of the first pyrolysis oil storage tank (152) and is stored there.

[0037] In this embodiment, the gas condensation tube (174) is described as having a coil-like shape and extending, but the present invention is not limited thereto. Referring to FIG. 4, the gas condensation tube (274) is formed to extend in a straight line along the length direction of the downstream pipe (173) of the introduction section. The gas condensation tube (274) is arranged coaxially with the downstream pipe (173) of the introduction section, so that the downstream pipe (173) of the introduction section and the gas condensation tube (274) form a double pipe. The gas condensation tube (174) illustrated in FIG. 3 and the gas condensation tube (274) illustrated in FIG. 4 are examples of the gas condensation means of the present invention.

[0038] Referring to Fig. 1, the introduction extension pipe (175) extends between the introduction upstream pipe (171) and the introduction downstream pipe (173). The introduction extension pipe (175) is positioned above the introduction upstream pipe (171) and the introduction downstream pipe (173) and extends generally horizontally. The upstream and downstream ends of the introduction extension pipe (175) are connected to the introduction upstream connection pipe (178) and the introduction downstream connection pipe (179), respectively. Although not shown, the introduction extension pipe (175) is also provided with a gas condensation pipe (174) illustrated in Fig. 3 or a gas condensation pipe (274) illustrated in Fig. 4. Accordingly, pyrolysis gas is condensed inside the introduction extension pipe (175) to produce pyrolysis oil. The pyrolysis oil produced in the introduction extension pipe (175) flows sequentially along the introduction downstream connection pipe (179) and the introduction downstream pipe (173) and is then introduced into the first pyrolysis oil storage tank (152) and stored there. In this embodiment, the introduction extension pipe (175) is described as extending generally horizontally, but it may be extended in a downward direction toward the downstream side in the flow direction of the pyrolysis gas. In this case, the pyrolysis oil produced in the introduction extension pipe (175) can be prevented from flowing toward the pyrolysis furnace (120).

[0039] The introduction upstream connection pipe (178) connects the introduction extension pipe (175) and the introduction upstream pipe (171). The introduction upstream connection pipe (178) is generally in the shape of an L-shaped pipe, and the upstream and downstream ends of the introduction upstream connection pipe (178) are connected to the introduction upstream pipe (171) and the introduction extension pipe (175), respectively.

[0040] The introduction downstream connection pipe (179) connects the introduction extension pipe (175) and the introduction downstream pipe (173). The introduction downstream connection pipe (179) is generally in the shape of an L-shaped pipe, and the downstream end and the upstream end of the introduction downstream connection pipe (179) are connected to the introduction downstream pipe (173) and the introduction extension pipe (175), respectively.

[0041] The intermediate pipe section (180) extends between the first pyrolysis oil storage tank (152) and the second pyrolysis oil storage tank (156), and connects the first outlet (154) formed in the first pyrolysis oil storage tank (152) with the second inlet (157) of the second pyrolysis oil storage tank (156). The pyrolysis gas in the first storage space of the first pyrolysis oil storage tank (152) flows along the intermediate pipe section (180) and flows into the second pyrolysis oil storage tank (156). The intermediate pipe section (180) includes an intermediate upstream pipe (181) extending upward from the first pyrolysis oil storage tank (152), an intermediate downstream pipe (183) extending upward from the second pyrolysis oil storage tank (156), an intermediate extension pipe (185) extending between the intermediate upstream pipe (181) and the intermediate downstream pipe (183), an intermediate upstream connection pipe (188) connecting the intermediate extension pipe (185) and the intermediate upstream pipe (181), and an intermediate downstream connection pipe (189) connecting the intermediate extension pipe (185) and the intermediate downstream pipe (183). The pyrolysis gas discharged from the first pyrolysis oil storage tank (152) flows sequentially along the middle section upstream pipe (181), the middle section upstream connection pipe (188), the middle section extension pipe (185), the middle section downstream connection pipe (189), and the middle section downstream pipe (183) and flows into the second pyrolysis oil storage tank (156).

[0042] The intermediate upstream pipe (181) extends upward from the first pyrolysis oil storage tank (152). The lower end, which is the upstream end of the intermediate upstream pipe (181), is connected to the first outlet (154) formed in the first pyrolysis oil storage tank (152), and the upper end, which is the downstream end of the intermediate upstream pipe (181), is connected to the intermediate upstream connection pipe (188). Although not shown, a gas condensation pipe (174) illustrated in FIG. 3 or a gas condensation pipe (274) illustrated in FIG. 4 is installed inside the intermediate upstream pipe (181). Accordingly, the pyrolysis gas is condensed inside the intermediate upstream pipe (181) to produce pyrolysis oil. The pyrolysis oil produced in the upstream pipe (181) of the middle section falls due to its own weight and flows into the first storage space of the first pyrolysis oil storage tank (152) and is stored there.

[0043] The intermediate downstream pipe (183) extends upward from the second pyrolysis oil storage tank (156). The lower end, which is the downstream end of the intermediate downstream pipe (183), is connected to the second inlet (157) formed in the second pyrolysis oil storage tank (156), and the upper end, which is the upstream end of the intermediate downstream pipe (183), is connected to the intermediate downstream connection pipe (189). Although not shown, a gas condensation pipe (174) illustrated in FIG. 3 or a gas condensation pipe (274) illustrated in FIG. 4 is installed inside the intermediate downstream pipe (183). Accordingly, the pyrolysis gas is condensed inside the intermediate downstream pipe (183) to produce pyrolysis oil. The pyrolysis oil produced in the downstream pipe (183) of the middle section falls due to its own weight and flows into the second storage space of the second pyrolysis oil storage tank (156) and is stored there.

[0044] The intermediate extension pipe (185) extends between the intermediate upstream pipe (181) and the intermediate downstream pipe (183). The intermediate extension pipe (185) is positioned above the intermediate upstream pipe (181) and the intermediate downstream pipe (183) and extends generally horizontally. The upstream and downstream ends of the intermediate extension pipe (185) are connected to the intermediate upstream connection pipe (188) and the intermediate downstream connection pipe (189), respectively. Although not shown, the intermediate extension pipe (185) is also provided with a gas condensation pipe (174) illustrated in FIG. 3 or a gas condensation pipe (274) illustrated in FIG. 4. Accordingly, pyrolysis gas is condensed inside the intermediate extension pipe (185) to produce pyrolysis oil. The pyrolysis oil produced in the intermediate extension pipe (185) may flow upstream and be stored in the first pyrolysis oil storage tank (152), or flow downstream and be stored in the second pyrolysis oil storage tank (156). In this embodiment, the intermediate extension pipe (185) is described as extending generally horizontally, but it may be extended in a downward slant toward the upstream or downstream side, or may be extended in a downward slant toward both sides, and this also falls within the scope of the present invention.

[0045] The intermediate upstream connecting pipe (188) connects the intermediate extension pipe (185) and the intermediate upstream pipe (181). The intermediate upstream connecting pipe (188) is generally in the shape of an L-shaped pipe, and the upstream and downstream ends of the intermediate upstream connecting pipe (188) are connected to the intermediate upstream pipe (181) and the intermediate extension pipe (185), respectively.

[0046] The intermediate downstream connecting pipe (189) connects the intermediate extension pipe (185) and the intermediate downstream pipe (183). The intermediate downstream connecting pipe (189) is generally in the shape of an L-shaped pipe, and the downstream end and the upstream end of the intermediate downstream connecting pipe (189) are connected to the intermediate downstream pipe (183) and the intermediate extension pipe (185), respectively.

[0047] In this embodiment having two pyrolysis oil storage tanks (152, 156), it is described that one intermediate pipe section (180) is provided, but the present invention is not limited thereto. If there is one pyrolysis oil storage tank, the intermediate pipe section (180) is not provided, and if there are three or more pyrolysis oil storage tanks, two or more intermediate pipe sections (180) are provided correspondingly, as those skilled in the art will understand, and this also falls within the scope of the present invention.

[0048] The discharge pipe (190) extends from the second pyrolysis oil storage tank (156). The pyrolysis gas in the second storage space of the second pyrolysis oil storage tank (156) flows along the discharge pipe (190) and is discharged to the outside. The discharge pipe (190) has a discharge pipe (191) extending upward from a second discharge port (158) formed in the second pyrolysis oil storage tank (156). Although not shown, a gas condensation pipe (174) illustrated in FIG. 3 or a gas condensation pipe (274) illustrated in FIG. 4 may be installed inside the discharge pipe (191). Accordingly, the pyrolysis gas may be condensed inside the discharge pipe (191) to produce pyrolysis oil. The pyrolysis oil produced in the discharge pipe (191) may fall due to its own weight and flow into the second storage space of the second pyrolysis oil storage tank (156) to be stored.

[0049] The filter (198) filters out harmful substances including foreign substances from the pyrolysis gas generated from the waste plastic pyrolysis device (110). In this embodiment, the filter (198) is described as being installed on the pipe (171) upstream of the introduction section of the introduction pipe section (170). In this embodiment, the harmful substances filtered out by the filter (198) are described as including dust and halogen compounds.

[0050] Now, the waste plastic processing equipment (100) that has been explained so far in terms of its composition will be explained in terms of its function.

[0051] First, before irradiating microwaves into the receiving space (124) of the pyrolysis furnace (120) to pyrolyze waste plastic (P), while the waste plastic (P) is received in the receiving space (124), the vacuum pump (145) is operated to primarily drastically reduce the amount of oxygen in the receiving space (124). Next, the nitrogen purge mechanism (148) is operated to purge nitrogen gas into the receiving space (124), thereby further reducing the amount of oxygen in the receiving space (124). By the operation of the vacuum pump (145) and the operation of the nitrogen purge mechanism (148), the amount of oxygen in the receiving space (124) is significantly reduced, thereby preventing the occurrence of a fire due to the high-temperature environment of the subsequent pyrolysis process.

[0052] Next, the magnetron (132) of the microwave supply (130) operates to generate microwaves. The microwaves pass through the waveguide (135) and are radiated into the receiving space (124). According to an experiment, the heating element (140) generates heat by the microwaves radiated into the receiving space (124) to reach a temperature of 600 to 800°C, and accordingly, the temperature of the receiving space (124) reaches 300 to 400°C. In addition, in the configuration of the waste plastic pyrolysis device (110) according to the above embodiment, the temperature of the ceiling of the receiving space (124) is maintained at 200°C, thereby reducing the possibility of a safety accident. At a temperature of 300°C or higher, the waste plastic (P) is emulsified, and the emulsified waste plastic is decomposed by the microwave and the high-temperature heating element (140) and vaporizes, thereby generating pyrolysis gas. The pyrolysis gas generated in the receiving space (124) is discharged from the receiving space (124) through the exhaust port (126). Although not shown, the waste plastic processing equipment (100) may further include an exhaust fan to discharge the pyrolysis gas generated in the receiving space (124) from the receiving space (124) and circulate it.

[0053] The pyrolysis gas discharged from the receiving space (124) of the pyrolysis furnace (120) flows sequentially along the introduction pipe (170), the first pyrolysis oil storage tank (152), the intermediate pipe (180), the second pyrolysis oil storage tank (156), and the discharge pipe (190).

[0054] As the pyrolysis gas flows through the introduction pipe (170), it is condensed by the gas condenser pipes (174, 274) provided in the introduction downstream pipe (173) and the introduction extension pipe (175), respectively, to produce pyrolysis oil. The pyrolysis oil produced in the introduction pipe (170) is stored in the first pyrolysis oil storage tank (152).

[0055] As the pyrolysis gas flows through the intermediate pipe section (180), it is condensed by the gas condenser provided in each of the intermediate upstream pipe section (181) and the intermediate downstream pipe section (183), thereby generating pyrolysis oil. The pyrolysis oil generated in the intermediate upstream pipe section (181) is stored in the first pyrolysis oil storage tank (152), and the pyrolysis oil generated in the intermediate downstream pipe section (183) is stored in the second pyrolysis oil storage tank (156).

[0056] As the pyrolysis gas flows through the discharge pipe (190), it is condensed by the gas condenser provided in the discharge pipe (191) to produce pyrolysis oil. The pyrolysis oil produced in the discharge pipe (191) is stored in the second pyrolysis oil storage tank (156).

[0057] According to the waste plastic processing equipment (100) according to the present embodiment, by directly irradiating microwaves to the waste plastic (P) by the waste plastic pyrolysis device (110), pyrolysis oil satisfying the pyrolysis oil conditions can be produced without using a catalyst. According to the conventional heater or LNG method, high molecular weight pyrolysis oil of carbon C20-40 is produced, so that this is additionally heat-treated with a catalyst to produce low molecular weight pyrolysis oil of carbon C10-20. Since the present embodiment does not use a catalyst, there are no problems with catalyst additional technology, catalyst life, or quality due to the use of a catalyst, and thus management is easy, the process is simplified, and costs can be reduced. According to the present embodiment, during pyrolysis, decomposition proceeds centered on carbon C16, so that pyrolysis oil having similar performance to a conventional catalyst-treated product can be produced.

[0058] While the present invention has been described through the above examples, the present invention is not limited thereto. The above examples may be modified or altered without departing from the spirit and scope of the present invention, and those skilled in the art will recognize that such modifications and variations also fall within the scope of the present invention.

Claims

1. A waste plastic pyrolysis device that uses microwaves as an energy source to pyrolyze waste plastic and generate pyrolysis gas; A pipe structure providing a pipe passage through which the pyrolysis gas flows as it is discharged from the waste plastic pyrolysis device; A gas condensation means for condensing the above pyrolysis gas to produce pyrolysis oil; and It includes a pyrolysis oil storage unit for storing the above pyrolysis oil, The above waste plastic pyrolysis device comprises a pyrolysis furnace that provides a space for pyrolysis target waste plastic to be accommodated therein, a microwave supply device that generates microwaves and supplies them to the space, and a heating element that absorbs microwaves and generates heat. The above heating element is arranged horizontally in the receiving space in the form of a plate, and the waste plastic to be decomposed is placed on the heating element so as to be in direct contact with it. In the above-mentioned receiving space, microwaves are radiated downward through a radiator disposed opposite to the heating element so that they penetrate the waste plastic to be pyrolyzed and are absorbed by the heating element. Waste plastic processing equipment.

2. In claim 1, The above heating element is a SiC heating element including silicon carbide (SiC). Waste plastic processing equipment.

3. In claim 1, The above waste plastic pyrolysis device further comprises a vacuum pump for exhausting air from the receiving space, The vacuum pump operates to reduce the amount of oxygen within the receiving space before microwaves are radiated into the receiving space. Waste plastic processing equipment.

4. In claim 3, The above waste plastic pyrolysis device further comprises a nitrogen purging mechanism for purging nitrogen gas into the receiving space. The above nitrogen purging mechanism operates to further reduce the amount of oxygen within the receiving space before microwaves are radiated into the receiving space after the vacuum pump is operated. Waste plastic processing equipment.

5. In claim 1, The above waste plastic pyrolysis device further comprises a nitrogen purging mechanism for purging nitrogen gas into the receiving space. The above nitrogen purging mechanism operates to cool the heated pyrolysis furnace after pyrolysis of the waste plastic to be pyrolyzed is completed. Waste plastic processing equipment.

6. A waste plastic pyrolysis device that uses microwaves as an energy source to pyrolyze waste plastic and generate pyrolysis gas; A pipe structure providing a pipe passage through which the pyrolysis gas flows as it is discharged from the waste plastic pyrolysis device; A gas condensation means for condensing the above pyrolysis gas to produce pyrolysis oil; and It includes a pyrolysis oil storage unit for storing the above pyrolysis oil, The above waste plastic pyrolysis device comprises a pyrolysis furnace that provides a space for pyrolysis target waste plastic to be accommodated therein, a microwave supply device that generates microwaves and supplies them to the space, and a heating element that absorbs microwaves and generates heat. The above gas condensation means is installed in at least a part of the pipe passage, so that pyrolysis oil is generated in the process of the pyrolysis gas flowing through the pipe passage, The above gas condensing means has a gas condensation tube through which a cooling fluid flows. Waste plastic processing equipment.

7. In claim 6, The above gas condenser is extended in a coil shape along the length of the above pipe passage. Waste plastic processing equipment.

8. In claim 6, The above gas condenser extends in a straight line along the length of the pipe passage to form a double pipe together with the pipe forming the pipe passage. Waste plastic processing equipment.

9. In claim 6, The above pyrolysis oil storage unit has a pyrolysis oil storage tank that provides a storage space in which pyrolysis oil is stored inside, The above piping structure has an introduction piping section that connects the storage space and the receiving space, The gas condensing means is installed in a section located above the storage space in the above introduction pipe section and not extending upwards as it goes downstream. Waste plastic processing equipment.

10. In claim 9, The above pyrolysis oil storage unit further includes an additional pyrolysis oil storage tank that provides additional storage space for storing pyrolysis oil therein. The above piping structure further includes an intermediate piping section connecting the storage space and the additional storage space, The above intermediate piping section has an intermediate upstream piping section extending upward from the pyrolysis oil storage tank, and an intermediate downstream piping section extending upward from the additional pyrolysis oil storage tank. The above gas condensation means is additionally installed in the above intermediate section upstream pipe and the above intermediate section downstream pipe, Waste plastic processing equipment.

11. A waste plastic pyrolysis device that uses microwaves as an energy source to pyrolyze waste plastic and generate pyrolysis gas; A pipe structure providing a pipe passage through which the pyrolysis gas flows as it is discharged from the waste plastic pyrolysis device; A gas condensation means for condensing the above pyrolysis gas to produce pyrolysis oil; and It includes a pyrolysis oil storage unit for storing the above pyrolysis oil, The above waste plastic pyrolysis device comprises a pyrolysis furnace that provides a space for pyrolysis target waste plastic to be accommodated therein, a microwave supply device that generates microwaves and supplies them to the space, and a heating element that absorbs microwaves and generates heat. The above heating element is placed below the waste plastic to be decomposed in the above receiving space, In the above-mentioned receiving space, microwaves penetrate the waste plastic to be pyrolyzed and are absorbed by the heating element. The above gas condensation means is installed in at least a part of the pipe passage, so that the pyrolysis oil is generated in the process of the pyrolysis gas flowing through the pipe passage. Waste plastic processing equipment.

12. In claim 11, Further comprising a filter for filtering out harmful substances from the above pyrolysis gas. Waste plastic processing equipment.

13. In claim 12, The above hazardous substances include dust and halogen compounds. Waste plastic processing equipment.

14. In claim 12, The above pyrolysis oil storage unit has a pyrolysis oil storage tank that provides a storage space in which pyrolysis oil is stored inside, The above piping structure has an introduction piping section that connects the storage space and the receiving space, The above filter is installed in the above introduction pipe section, Waste plastic processing equipment.

15. A pyrolysis furnace that provides a space for receiving waste plastics subject to pyrolysis inside; A microwave supply device that generates microwaves and supplies them to the receiving space; and A heating element is disposed at the bottom of the waste plastic in the pyrolysis furnace, comes into direct contact with the waste plastic, and absorbs the supplied microwaves to pyrolyze the waste plastic. Waste plastic pyrolysis device.

16. In claim 15, In the above-mentioned receiving space, microwaves are radiated downward through a radiator disposed opposite to the heating element so that they penetrate the waste plastic to be pyrolyzed and are absorbed by the heating element. Waste plastic pyrolysis device.

17. In claim 15, The above heating element is a plate-shaped element and is horizontally arranged in the receiving space. Waste plastic pyrolysis device.

18. A waste plastic pyrolysis device that uses microwaves as an energy source to pyrolyze waste plastic and generate pyrolysis gas; A pipe structure providing a pipe passage through which the pyrolysis gas flows as it is discharged from the waste plastic pyrolysis device; A gas condensation means for condensing the above pyrolysis gas to produce pyrolysis oil; and It includes a pyrolysis oil storage unit for storing the above pyrolysis oil, The above waste plastic pyrolysis device comprises a pyrolysis furnace that provides a receiving space in which waste plastic to be pyrolyzed is received, a microwave supply device that generates microwaves and supplies them to the receiving space, a heating element that absorbs microwaves and generates heat, a vacuum pump that discharges air in the receiving space, and a nitrogen purging device that purges nitrogen gas into the receiving space. The above heating element is arranged horizontally in the receiving space in the form of a plate, and the waste plastic to be decomposed is placed on the heating element so as to be in direct contact with it. In the above-mentioned receiving space, microwaves are radiated downward through a radiator positioned opposite to the heating element, and are directly irradiated to the waste plastic to be thermally decomposed, and then penetrate the waste plastic to be thermally decomposed and are absorbed by the heating element. The vacuum pump operates before microwaves are radiated into the receiving space to reduce the amount of oxygen within the receiving space, The above nitrogen purging mechanism operates before microwaves are radiated into the receiving space after the vacuum pump is operated to further reduce the amount of oxygen in the receiving space. The above nitrogen purging mechanism is additionally operated after the pyrolysis of the waste plastic to be pyrolyzed is completed to cool the heated pyrolysis furnace. The above piping structure has an inlet downstream pipe through which pyrolysis gas flowing into the pyrolysis oil storage unit flows and extends upward from the pyrolysis oil storage unit, and an outlet pipe through which pyrolysis gas discharged from the pyrolysis oil storage unit flows and extends upward from the pyrolysis oil storage unit. The above gas condensing means has a gas condensation pipe through which a cooling fluid flows and which is arranged within the pipe passage, The above gas condenser is installed in the downstream pipe of the introduction section and the discharge section pipe, respectively. Pyrolysis oil is generated from the pyrolysis gas discharged from the pyrolysis storage unit by the gas condenser installed in the discharge pipe and stored in the pyrolysis oil storage unit. Waste plastic processing equipment.

19. A waste plastic pyrolysis device that uses microwaves as an energy source to pyrolyze waste plastic and generate pyrolysis gas; A pipe structure providing a pipe passage through which the pyrolysis gas flows as it is discharged from the waste plastic pyrolysis device; A gas condensation means for condensing the above pyrolysis gas to produce pyrolysis oil; and It includes a pyrolysis oil storage unit for storing the above pyrolysis oil, The above waste plastic pyrolysis device comprises a pyrolysis furnace that provides a space for pyrolysis target waste plastic to be accommodated therein, a microwave supply device that generates microwaves and supplies them to the space, and a heating element that absorbs microwaves and generates heat. The above heating element is arranged horizontally in the receiving space in the form of a plate, and the waste plastic to be decomposed is placed on the heating element so as to be in direct contact with it. The above gas condensation means is installed in at least a part of the pipe passage, so that pyrolysis oil is generated in the process of the pyrolysis gas flowing through the pipe passage, The above gas condensing means has a gas condensation tube through which a cooling fluid flows, The above gas condenser is placed within the above pipe passage, The above pyrolysis oil storage unit provides a storage space in which pyrolysis oil is stored inside, and includes a pyrolysis oil storage tank having an inlet for gas inflow and an outlet for gas discharge, and an additional pyrolysis oil storage tank providing an additional storage space in which pyrolysis oil is stored inside, and having an additional inlet for gas inflow and an additional outlet for gas discharge. The above piping structure has an inlet pipe extending upward from the inlet, a discharge pipe extending upward from the discharge pipe, an additional inlet pipe extending upward from the additional inlet and communicating with the discharge pipe, and an additional discharge pipe extending upward from the additional discharge port. The pyrolysis gas is discharged from the pyrolysis oil storage unit through the above additional discharge pipe, The above gas condenser is installed in the inlet pipe, the discharge pipe, the additional inlet pipe, and the additional discharge pipe, respectively. Pyrolysis oil is generated from the pyrolysis gas discharged from the pyrolysis oil storage unit by the condenser installed in the additional discharge pipe and stored in the additional pyrolysis oil storage tank. Waste plastic processing equipment.

Images