WO2003064561A1

WO2003064561A1 - Method and plant for converting plastic into oil

Info

Publication number: WO2003064561A1
Application number: PCT/JP2003/000413
Authority: WO
Inventors: Yoichi Wada
Original assignee: Murata, Jiro; Ishikawa, Yasuo
Priority date: 2002-01-25
Filing date: 2003-01-20
Publication date: 2003-08-07
Also published as: TW200302867A; US20050075521A1; KR20040048368A

Abstract

A method for converting a plastic into an oil, which comprises melting a plastic as a raw material in a melting section (31) so as to form an expanded plastic, sending the expanded plastic to a first step decomposition cylinder (47) and, arranged adjacent thereto, a second step decomposition cylinder (48), to thereby depolymerize the plastic to a light secondary decomposition gas, followed by separation, cooling the separated secondary decomposition gas by the use of condensers (37,38) to an oil, followed by recovering in oil storage tanks (42,43). The method can be advantageously employed for completely decomposing a large amount of plastics by heating and also for treating a toxic gas.

Description

Description Oiling method and oiling plant for plastics [Technical field]

The present invention relates to a method for liquefying plastics for collecting oil from plastics and a liquefied blunt.

[Background technology]

Various oil conversion plants for collecting oil from waste plastics have been proposed, but none of them has been sufficiently decomposed and is actually operating practically.

Accordingly, the present applicant has previously developed a small-sized and simple-structured reverse heat gradient type oiling blunt disclosed in Japanese Patent Application Laid-Open No. 2000-167774.

However, in this oil conversion plant, 1) it is possible to reliably convert the plastic to oil when the amount of processed plastic is small, but it is difficult to completely convert the plastic to oil when the amount of processed plastic is large.2) PVC ( Polyvinyl chlorid) When dissolving plastic, hydrogen chloride gas is generated in the dissolution part, but this hydrogen chloride gas is not sufficiently treated, 3) Not oiled off gas is not sufficiently treated, etc. There was a problem.

The present invention has been made mainly in view of these problems. An oiling method capable of oiling a large amount of plastics, treating hydrogen chloride gas, and completely treating off-gas, and the like. The main purpose is to provide a petrochemical plant. [Disclosure of the Invention]

Therefore, the oiling method of the present invention is characterized in that a plastic is heated and dissolved to form a foamed plastic, and the foamed plastic is taken out, heated and depolymerized, and then cooled to produce an oil. And At this time, the foamed plastic should be pulled out diagonally upward, preferably at an angle of 25 to 30 ° with respect to the horizontal. Further, it is preferable to heat the foamed plastic while pulling the foamed plastic diagonally upward, and to heat the foamed plastic at a higher temperature as the foamed plastic is positioned higher. Further, food oil, animal oil or mineral oil may be added to the decomposed plastic and heated to produce a foamed plastic composed of a mixture thereof.

According to the oiling method of the present invention, hydrogen chloride gas generated when plastics are dissolved is separated from other decomposed gases, and then reacted with slaked lime to recover chlorinated calcium. In addition, the off-gas that has not been turned into oil may be treated by catalytic decomposition with high-temperature ceramics.

Further, the oil-forming plant of the present invention comprises a dissolving section for heating and melting the plastic to form a foamed plastic, and removing the foamed plastic, heating and depolymerizing, and then cooling to produce oil. And a disassembly section that performs the following. In this oil conversion plant, the decomposition section may be provided with a take-out means for taking up and taking out the foamy plastic obliquely upward, preferably at an angle of 25 to 30 ° with respect to the horizontal. Further, it is preferable that the decomposition section is provided with a heating means for heating while pulling the foamy plastic diagonally upward, and for heating the foamy plastic at a higher temperature as the foamed plastic is positioned upward. Further, an oil injection means for injecting food oil, animal oil, or mineral oil into the joint between the melting part and the decomposition part may be provided. Further, the melting part may be formed by a plurality of melting cylinders having different temperature distributions, and the decomposition part may be formed by a plurality of inclined decomposition cylinders having different temperature distributions. Further, the oil conversion plant of the present invention may be provided with a dechlorination device for treating the hydrogen chloride gas generated in the dissolving section. The dechlorination device is used for decomposing the hydrogen chloride gas and other cracked gas. And a reactor in which hydrogen chloride gas separated by the separator is reacted with slaked lime to form calcium chloride. Further, it is preferable to provide an off-gas processing device for catalytically decomposing and processing off-gas that has not been generated as oil after cooling in the decomposition section with high-temperature ceramics.

Furthermore, in the oil conversion plant of the present invention, it is preferable that a residue collecting means is provided at the upper end of the final stage of the decomposition tube among the multistage decomposition tubes. The lower opening is preferably formed of a cylinder positioned in an inert gas atmosphere heavier than air.

Furthermore, the oil conversion plant of the present invention is provided with a hopper for storing and supplying the plastic to the melting section, and the hopper is preferably provided with a lead screw having spiral blades. It is preferable to provide a non-heated portion between the hopper and the melting portion, which is formed by a region not heated with a predetermined length. Further, the plurality of melting cylinders are provided with a lead screw having a spiral blade for transporting the plastic, and the lead screw of the melting cylinder positioned at the head is adjusted to the lead screw pitch of the other melting cylinder. It is recommended that the pitch be larger than the pitch of the blades.

Still further, in the oil conversion plant of the present invention, the melting section and the decomposition section are formed by an inner cylinder, an outer cylinder formed on the outer periphery of the inner cylinder, and hot air circulated between the inner cylinder and the outer cylinder. A hot air space, and a temperature sensor for detecting the temperature of the melting part or the decomposition part. Further, when the temperature sensor detects an abnormal temperature exceeding a predetermined temperature, the carbon dioxide gas is sent into the hot air space. A carbon dioxide supply device may be provided.

Still further, the oil conversion plant of the present invention comprises: It comprises an outer cylinder formed on the outer circumference of the inner cylinder, and a hot air space formed between the inner cylinder and the outer cylinder and circulating hot air, and further burns hot air to supply the hot air space. It is preferable to provide a hot air generator for generating the hot air and a drying device for drying the plastic supplied to the melting furnace, and supply the air in the drying device to the hot air generator to deodorize by combustion. Alternatively, the air in the drying device may be supplied to the off-gas treatment device and decomposed by catalytic decomposition with a high-temperature ceramics.

Furthermore, the oil conversion plant of the present invention uses a telescopic cylinder formed to be freely expandable and contractable for a part of the melting cylinder, and this telescopic cylinder is arranged on the inner cylinder and on the outer periphery of the inner cylinder, and one end is formed inside. The bellows may be formed of a bellows fixed to the cylinder and having the other end slidable with respect to the inner cylinder, and an outer cylinder fixed to the other end of the bellows and containing the inner cylinder slidably therein.

Still further, in the oil conversion plant of the present invention, the dissolving section includes an inner cylinder, an outer cylinder formed on the outer periphery of the inner cylinder, and a liquid heat medium circulated between the inner cylinder and the outer cylinder. It is preferable that the heat medium space further include a heat medium supply device for supplying a liquid heat medium to the heat medium space.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing the basic principle of the present invention.

FIG. 2 is a configuration diagram showing an embodiment based on the basic principle of the present invention. FIG. 3 is a perspective view of an oil conversion plant showing one embodiment of the present invention. FIG. 4 is a front view of an oil conversion plant showing one embodiment of the present invention. FIG. 5 is a plan view of an oil conversion plant showing one embodiment of the present invention. FIG. 6 is an explanatory diagram of a schematic configuration of FIG.

FIG. 7 is an explanatory diagram of a schematic configuration of FIG.

FIG. 8 is a cross-sectional view of the melting cylinder. FIG. 9 is a cross-sectional view of the disassembly tube. .

FIG. 10 is a block diagram of the dechlorination unit. ,

FIG. 11 is a configuration diagram of an off-gas processing unit.

FIG. 12 is a schematic structural explanatory view showing another embodiment.

FIG. 13 is a configuration diagram of a joining portion between a melting portion and a disassembling portion.

FIG. 14 is a diagram showing the recovery rate according to the plastic to be treated. FIG. 15 is an explanatory view of a state in which the foamed plastic is pulled up.

FIG. 16 is a cross-sectional view of the hopper.

FIG. 17 is a perspective view of a non-heating section.

FIG. 18 is a configuration diagram of a sludge tank.

FIG. 19 is a configuration diagram of the telescopic cylinder.

FIG. 20 is a schematic configuration diagram of an accident prevention system and a deodorizing system. ₍ FIG. 21 is a schematic diagram showing another embodiment. [Best Mode for Carrying Out the Invention]

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a conceptual diagram for explaining the basic principle of the method for liquefying plastic according to the present invention. The raw material plastic is melted at a temperature of 200 ° C. (up to 350 ° C.) and stored in the storage unit 1. Then, the melted plastic (dissolved plastic) is slanted upward by the decomposition cylinder 13 Raised.

Here, the disassembly tube 13 includes an inner tube 2, an outer tube 6 forming a hot air space 4 around the inner tube 2, and a lead screw 7. The lead screw 7 includes a rotating shaft 14 and a spiral blade 8, and is rotated at a speed of 4 to 5 rotations Z by the motor 12. Hot air is supplied to the hot air space 4 from the pipe 10, and the temperature in the inner cylinder 2 is changed to gasification of plastic. It is maintained at 350-620 for depolymerization.

The dissolved plastic conveyed in the inner cylinder 2 by the lead screw 7 is firstly decomposed (the first heavy gas state gasified from the dissolved state) below the decomposing cylinder 13 to become the first decomposed gas. Further, the primary decomposition gas is sent at a low speed above the decomposition cylinder 13 by the lead screw 7 and is maintained at 35 O: ~ 620 ° C by hot air supplied from the pipe 15. It is secondarily decomposed in the cylinder 2 (the state in which the plastic is depolymerized and turned into oil if cooled) to become a lightly decomposed gas.

If the secondary decomposition of all the oil components contained in the raw material plastic is performed at the top of the cracking cylinder, only one cracking cylinder is sufficient, but it is connected to the storage unit 1 using two cracking cylinders. It is also possible to connect the second stage disassembly tube to this first stage disassembly tube.

An outer box 5 is formed outside the storage section 1 to form a hot air space 3, and hot air is sent to the hot air space 3. The plastic supplied to the storage unit 1 is heated to 200 to 350 ° C and becomes molten plastic in p. A foamed plastic (foamed plastic) f is formed on the surface. The foamed plastic f is heated while being pulled up obliquely by the lead screw 7 in which the shaft end 14a is immersed in the molten plastic mp, but at this time the contact area with heat increases, so it is surely decomposed. (Depolymerization) to become secondary decomposition gas. The secondary cracked gas is collected from the pipe 9 and liquefied by cooling and collected in the oil storage tank.

The speed at which the foamed plastic f is pulled up is preferably 30 to 60 cmZ. If it is less than this, the transport efficiency will be poor. If it exceeds this, sufficient decomposition will not be possible. For example, the foamed plastic f is spirally pulled up by the lead screw 7 as shown in FIG. 15, and the speed of the spiral movement at this time is preferably 30 to 6 ° cm / min. This speed The degree is adjusted, for example, by the pitch p of the lead screw 7. In this way, the foamed plastic f is conveyed inside the inner cylinder 2 at the aforementioned speed and slowly heated, so that it is sufficiently decomposed in the first decomposition temperature range and the second decomposition temperature range ( Depolymerization). It is preferable to heat the foamed plastic for about 14 to 15 minutes at around 600 ° C until it is completely decomposed.

The processing temperature varies depending on the type of plastic as the raw material. The temperature of the force storage unit 1 is preferably set to a temperature at which the molten plastic mp becomes foamy (200 to 350 ° C), For decomposition, it is important to reduce the temperature gradient, maintain the foamy state for a long time, and increase the contact area with heat. For this purpose, the disassembly tube 13 is preferably provided to be inclined with respect to the horizontal. In addition, in the inclined disassembly tube 13, hot air is blown into the upper part and circulated from the upper part to the lower part, so that the temperature rises sequentially from the lower part to the upper part. This method is called the reverse thermal gradient method.

In order to hold the foamed plastic f well for a long time, it is preferable to set the inclination angle の of the disassembling cylinder 27 to 25 ° to 30 ° as shown in FIG. If the inclination angle 0 of the disassembly tube 27 is set to less than 25 °, the foamy plastic f flows sideways quickly and disappears in a short time, and if the inclination angle 0 is set to exceed 30 °, Due to gravity, it is difficult to pull the foam plastic プラスチック upward from the surface of the melted plastic mp for a long distance. In this case also, the foam plastic f disappears in a short time.

In FIG. 2, the storage part 29 of the molten plastic mp is formed at a connection part where the supply cylinder 28 and the decomposition cylinder 27 are connected in a V-shape. The supply cylinder 28 is composed of an inner cylinder 20 and an outer cylinder 21, between which hot air is supplied via a pipe 22, and the inside of the inner cylinder 20 is maintained at 200 to 350.

Disassembly cylinder 27 is composed of inner cylinder 25, outer cylinder 17 and lead screw 24. The lead screw 24 is mounted such that the lower end of the shaft 23 is rotatably supported by the lower wall of the storage portion 29. Between the inner cylinder 25 and the outer cylinder 17, heated air at 450 to 62 ° C. is supplied from a hot air generator through a pipe 26 c. Then, the heated air descends inside the disassembly tube 27, is drawn out from the pipe 26b below the disassembly tube, and is circulated so as to flow in from the upper tube 26a. When the high-temperature air circulates from the upper part to the lower part in the decomposition tube 27 in this way, the temperature distribution in the decomposition tube 27 is formed so that the temperature increases from the bottom to the top. The lower part of decomposition tube 27 is maintained at 300 to 450 ° C for primary decomposition, and the upper part of decomposition tube 27 is heated to nearly 600 ° C for secondary decomposition. You. ―

In the storage section 29, the foamed plastic f is ripened, and the foamed plastic f is transported in a favorable state so as to rise in the inclined decomposition cylinder 27, and is heated during the transportation to become a decomposition gas. . Since the decomposition tube 27 and the supply unit 28 are connected in a V-shape and the storage unit 29 is completely closed by the molten plastic mp, the decomposition gas flows back from the decomposition tube 27 to the supply tube 28 In addition, air is prevented from entering the decomposition cylinder 29 from the outside through the storage part 29, and there is no danger of explosion.

Next, an oil plant that applies this plastic oil method will be described.

In FIG. 3 to FIG. 7, an oil conversion plant 30 of the present invention includes, for example, a dissolving section 31 for dissolving waste plastic as a raw material, and a primary decomposition and dissolution of the plastic dissolved in the dissolving section 31. Decomposition section 3 2 for secondary decomposition, dechlorination section 3 3 for dechlorination when processing chlorine-containing PVC, and off-gas processing section 3 4 for processing off-gas generated during plastic dissolution and decomposition And first and second hot blast stoves 35, 36 for generating hot air as a heat source during melting and decomposition. As shown in FIG. 6, the melting section 31 includes a first melting cylinder 31 a that connects a hopper 41 into which the plastic material is supplied via a non-heating section 410, and a first melting cylinder 31. The second melting tube 3 1b, whose tip is connected below the tip of 1a and is orthogonal to the first melting tube 31a, and the second end of which is connected below the tip of the second melting tube 31b. The third melting cylinder 3 1c orthogonal to the melting cylinder 3 1b and the fourth melting cylinder 3 1d whose rear end is connected below the tip of the third melting cylinder 31 and is orthogonal to the third melting cylinder 3 1c , And is configured. In this way, the first to fourth melting cylinders 31a, 31b ... 31d are arranged in a rectangular shape as a whole, and the melted plastic falls sequentially from the leading end of the disassembling cylinder to the rear end of the joining melting cylinder. To be sent. In addition, these melting tubes 31a to 31d may be connected horizontally.

As shown in FIG. 16, the hopper 41 has a funnel-shaped casing 411, a cover 4 1 2 covering the upper surface of the casing 4 1 1, and a motor disposed at the center of the cover 4 1 2. 4 13 and a rotating shaft 4 14 a connected to the motor 4 13 and extending through the lid 4 12 into the casing 4 11 1 and a spiral blade 4 1 4 attached to the rotating shaft 4 14 a It is composed of the lead screw 4 14 composed of b and b. The spiral blades 4 14 b of the lead screw 4 14 ′ have a rotor shape as a whole that conforms to the shape of the casing 4 14. An interval W of about 2 to 5 cm is provided between the inner wall of the casing 4 14 and the outer periphery of the spiral blade 4 14 b. The lead screw 414 is rotated at a predetermined speed by the motor 413 to prevent light plastic from being clogged in the hopper 41. Then, the heavy plastic falls through the space W between the inner wall of the casing 4 14 and the outer periphery of the spiral blade 4 14 b, and the light plastic pieces are surely not heated by the lead screw 14 14. Sent in 4 1 0

The non-heating part 4 10 is formed of a cylinder and connected to the lower part of the hopper 4 1 (Fig. 17). A motor 42 is provided at an end of the non-heated portion 410, and the motor 42 has a lead screw shared with a lead screw 13 7 disposed in a melting tube 31a to be described later. 1 3 7 is connected. The lead star 13 7 is rotated by the motor 42 and slowly sends the plastic pieces sent from the hopper 41 forward to the melting tube 31 a. The non-heating section 410 is not heated by hot air unlike the melting tube 31 described later. Therefore, since the mounting portion of the hopper 41 is separated from the melting cylinder 31, melting of the plastic does not start near the mounting portion of the hopper 41, and the lead screw 13 7 is formed by viscous resistance of the melted plastic. Can be prevented from stopping. In other words, by separating the dissolving portion of the plastic from the mounting portion of the hopper 41, the unmelted plastic portion is lengthened, and the unmelted plastic pushes the molten plastic. .

The melting cylinder 31 is composed of a rectangular outer box 13 6 and an inner cylinder i 31 provided in the outer box 13 (FIG. 8). In the inner cylinder 131, a lead screw 1337 having a rotating shaft 133 and a spiral blade 132 provided around the rotating shaft 133 is provided. The pitch of the lead stalk 13 of the first melting cylinder 31a is set to be larger than the pitch of the lead screw 1337 of the other melting cylinders 31b, 31c and 31d. This is because the set temperature of the first melting cylinder 31a is lower than that of the other melting cylinders, as described later, so that the residence density of the plastic is reduced and the resistance is reduced. The lead screw 1337 is rotated by a motor. For example, the first melting cylinder 31a is rotated by a motor 42 (FIGS. 4 and 5), and the second melting cylinder 31b is rotated by a motor 55. Rotated.

Further, the inner cylinder 13 1 is provided with a plurality of heat absorbing blades 14 on the outer periphery thereof. A hot air space 135 is formed between the inner cylinder 13 1 and the outer box 1 36. The first melting cylinder 31a is controlled at 190 to 200 ° C, and the inside of the second melting cylinder 31b is controlled at 210 to 230 ° C. The third melting cylinder 3 1c

At 230, it is controlled to 260 ° C, and the fourth melting cylinder 31 d is 300

Controlled at 34 ° C. As described above, the four melting cylinders 31a, 31b ... 31d were arranged in a rectangular shape, and the temperature of each melting cylinder was gradually increased. A) Removal of plastic containing chlorine such as vinyl chloride. To ensure a sufficient residence time (for example, 20 minutes) to reliably perform chlorine, and b) To ease the temperature control by gradualizing the temperature distribution by using multiple stages, and c) The first melting cylinder This is to prevent the welding of the plastic to the rotating shaft 133 near the hopper 41 by lowering the temperature of 31a, and d) to shorten the length of the entire plant.

Hot air is supplied into each melting tube 31 from the first hot air furnace 35 through a pipe 70, and the hot air is sent from the downstream side where the plastic is sent to the upstream side. Therefore, the inside of each melting cylinder 31 has a reverse heat gradient. The circulation of hot air in each melting cylinder 31 is performed by blowers 56, 57, 58 (Fig. 4) and 60 (Fig. 7). In addition, a smoke tube 59 is connected to the first and second hot air generators 35 and 36. The chimney 59 is formed in an inverted U-shape with branch pipes 59a and 59b and an outlet 59c (Fig. 4).

The disassembly section 32 is provided adjacent to the first-stage disassembly tube 47 controlled at 350 to 420 ° C and 450 to 580 ° C. And a second-stage disassembly tube 48 controlled by C (Fig. 7). The disassembly cylinders 47 and 48 are disposed at an angle of 25 to 30 ° with respect to the horizontal plane. The tip of the fourth melting cylinder 31 d is connected to the inside of the first-stage disassembling cylinder 47, and this connecting part forms a storage section for the molten plastic.

The first stage disassembly tube 47 is composed of two unit disassembly tubes 47a and 47b which are separated by a partition plate 256 and are formed in two rows on the left and right (Fig. 9). And The unit disassembly cylinders 47 a and 47 b are supplied with the inner cylinder 255, a plurality of heat absorbing fins 25 3 provided on the outer periphery of the inner cylinder 255, the lead screw 150, and hot air. Heat space 25 4. Each lead screw 150 includes a rotating shaft 25 1 and a spiral blade 25 2 and is rotated by motors 51 and 52 (FIG. 5).

The second-stage disassembly tube 48 has almost the same structure as the first-stage disassembly tube 47, and the unit disassembly tubes 48a and 48b (Fig. 6) are provided with an inner tube 148, respectively. You. A lead screw 149 is provided in the inner cylinder 148, and the lead screw 149 is slowly (4 to 5 turns) driven by the motors 53, 54 (Figs. 5 and 7). / Min) and rotated.

At the upper end of the inner cylinder 255 of the first stage decomposition cylinder 47, a superheater 151 is provided to heat the passing decomposition gas to 580-620 ° C (Fig. 7). ). The cracked gas that has been secondarily decomposed in the first-stage decomposition cylinder 47 is drawn out through the superheater 15 1 and the piping 49, and is passed through the scrubber 60 for cleaning the condenser 3 7 (the 5). Then, the decomposed gas is cooled by the condenser 37 to be turned into oil, and this oil is stored in the oil storage tank 42 through the pipe 46. Part of the oil stored in the oil storage tank 42 is supplied to the hot air generators 35, 36 via the service tank ST1. A valve 49a for adjusting the flow rate of the decomposition gas flowing in the pipe 49 is provided in the middle of the pipe 49. It is necessary to send only the lightly decomposed gas completely secondarily decomposed by the first decomposing cylinder 47 to the condenser 37, but the decomposed gas derived from the pipe 49 is completely decomposed. Includes a slightly heavier incompletely cracked gas that has not been removed. When the amount of the decomposed gas discharged from the pipe 49 is small, the incompletely decomposed gas cannot return to the rising portion of the pipe 49 and returns to the first-stage decomposed cylinder 47 via the falling cylinder 120. Is sent to the second-stage decomposition column 48, As the amount of discharge is increased, the flow of the decomposed gas is increased, and the incompletely decomposed gas is sent to the condenser 37 beyond the rising part of the pipe 49. Therefore, the amount of the decomposed gas derived from the pipe 49 is adjusted by the valve 49 a to prevent the incompletely decomposed gas from being sent to the condenser 37. As described above, the first-stage cracking cylinder 47 is controlled at 350 to 420 ° C, so the first-stage cracking cylinder 47 has an oil component equivalent to gasoline with low cracking temperature, kerosene, and light oil. Some of the corresponding components undergo secondary decomposition after primary decomposition. Here, the gas in an insufficiently decomposed state is completely decomposed by the superheat 15 1. Then, the decomposition gas decomposed in this way is cooled by the capacitor 37 and turned into oil. Gas that is not separated into oil by the condenser 37 is sucked through a pipe 46 having a pump P and collected as off-gas in an oil storage tank 42.

The foamy plastic component that is not completely decomposed in the second-stage disassembly tube 4 7 is supplied to the lower end of the second-stage disassembly tube 4 8 via the dropping tube 1 20, and the second-stage disassembly tube 4 It is sent diagonally upward by lead screw 14 9 in 8. The inside of the second stage disassembly tube 48 is 450-580. Since it is controlled at the temperature of C, the second-stage decomposition column 48 completely decomposes the residual portion of kerosene, light oil equivalent components, and heavy oil components completely. Residues such as metal, mud, etc., which were put in with the plastic, are collected in a sludge tank 40 via a sludge pipe 40a.

As shown in Fig. 18, sludge tank 40 stores water 40b, and wire mesh 40c is provided in water 40b, and the residue is collected on wire mesh 40c. Is done. By removing the wire mesh 40c from the sludge tank 40, the residue can be removed from the sludge tank 40. The upper surface of the sludge tank 40 is partially covered with a lid 40d having an opening 40e. Above the water 40 b in the sludge tank 40, the air is heavier than air such as carbon dioxide. Inert gas 40f is filled, and the lower end of the sludge pipe 40a is located in the inert gas 40f. A gas cylinder 40 g is connected to the sludge tank 40, and an inert gas 40 f is supplied from the gas cylinder 40 g into the sludge tank 40. Part of the inert gas 40f supplied from the gas cylinder 40g overflows from the opening 40e. Thus, by locating the lower end of the sludge pipe 40a in the inert gas 40f, the inflow of air from the sludge pipe 40a into the second-stage decomposition pipe 48 is effective. And the risk of explosion is eliminated. Also, if the lower end of the sludge pipe 40a is positioned in the water 40b, the light residue will be lifted by the buoyancy of the water, and the lower end of the sludge pipe 40a will be clogged. This was prevented by positioning the lower end of the sludge pipe 40a in the gas 40f, and the residue was allowed to fall smoothly into the water 40b.

Hot air is supplied to the upper part of the first-stage and second-stage disassembly tubes 47 and 48 from the second hot-air generating furnace 36 via pipes 71, 71a and 71b (Fig. 5). The hot air is extracted from the lower part of the decomposition tubes 47 and 48 and is returned to the upper part, and is circulated through the probes 170 and 171. In this way, the decomposition tubes 47 and 48 are formed with an inverse heat gradient in which the temperature decreases from the upper part to the lower part. Further, hot air from the first hot air generating furnace 35 is supplied to the melting section 31, and the hot air is circulated by the blower 60 in, for example, the fourth melting cylinder 31 d (FIG. 7). . At the upper end of the inner cylinder 144 of the second stage disassembly cylinder 48, a pipe 50 connected to the condenser 38 via a scrubber 61 for alkaline cleaning is arranged (FIG. 5). The decomposed gas decomposed in the second-stage decomposing cylinder 48 is sent to a scrubber 61 through a pipe 50, and further sent to a condenser 38. The cracked gas sent to the capacitor 38 is turned into oil by cooling. The liquefied oil is sent to an oil storage tank 43 via a pipe 86, and a part of this oil is sent to the first and second hot air generators 35, 36 via a service tank ST2. You. The condensers 37 and 38 are cooled by the cooling tower CT (Fig. 3).

The first and second stage disassembly cylinders 47 and 48 are connected to pipes 101 and 102 connected to the common exhaust pipe 100, respectively. Then, the exhaust gas of the first and second stage disassembly tubes 47 and 48 is discharged to the outside from the collective exhaust pipe 100 via the pipes 101 and 102. The gas not converted into oil by the capacitor 38 connected to the second-stage disassembly tube 48 is recovered by the pump P through the pipe 86 to the oil storage tank 43.

A telescopic cylinder 700 is used for a part of the melting cylinder 31 and the disassembling cylinders 47 and 48 described above. The telescopic cylinder 700 is formed by a bellows part 700 and a slide part 720 (FIG. 19). The bellows portion 701 is composed of a bellows 703 and a bellows inner cylinder 704 disposed therein, and the entire length of the bellows inner cylinder 704 is longer than the entire length of the bellows 703. Is done. The bellows 703 and the bellows inner cylinder 704 are installed such that one end thereof is aligned, and the bellows inner cylinder 704 projects from the other end of the bellows 703. A support cylinder 705 is arranged on the outer periphery of the protruding bellows inner cylinder 704, and the bellows inner cylinder 704 and the support cylinder 705 form a slide portion 702. The inner diameter of the support cylinder 705 is formed slightly larger than the outer diameter of the bellows inner cylinder 704, and the inner peripheral surface of the support cylinder 705 and the outer peripheral surface of the bellows inner cylinder 704 form a sliding surface. In FIG. 19, an inner cylinder 706 formed to have the same diameter as the bellows inner cylinder 704 is disposed at a position where the bellows inner cylinder 704 of the support cylinder 705 is not located. Further, corresponding step portions 704a and 706a are formed at the butting side ends of the bellows inner cylinder 704 and the inner cylinder 706, respectively. In this case, the opposing surfaces of both step portions 704a and 706a form a sliding surface.

As described above, the expansion and contraction cylinders 700 arranged in a part of the melting cylinder 31 and the disassembling cylinders 47 and 48 are heated by heating the melting cylinder 31 and the disassembling cylinders 47 and 48. Thermal expansion In the case where the swelling occurs, it plays a role in absorbing the amount of expansion. That is, for example, when the first melting cylinder 31a is heated from room temperature to about 200 ° C. and its overall length is extended by thermal expansion, the telescopic cylinder 70 arranged in a part of the first melting cylinder 31a A value of 0 contracts the bellows 703 so as to move the bellows inner cylinder 704 to the slide portion 702 side, thereby absorbing the expansion amount of the first melting cylinder 31a.

Further, the telescopic cylinder 700 shown in FIG. 19 is provided with the slide position of the bellows inner cylinder 704 outside the bellows part 701, and a support cylinder 7 having a larger diameter than the bellows inner cylinder 704. Since the sliding portion 702 is formed by using 005, the bellows inner cylinder 704 can be made thicker without reducing the inner diameter of the bellows inner cylinder 704. . As a result, deformation of the telescopic cylinder 700 can be prevented, and thus, the bellows 703 caused by deformation of the telescopic cylinder 700 can be prevented from being damaged. It is possible to prevent fires caused by spills.

Next, details of the dechlorination apparatus 33 will be described.

The pipes 75, 76, 77 extending from the top of the melting cylinders 31a, 31b, 31c of the melting part 31 are connected to the pipe 78 (Fig. 5), and the pipe 78 is the first. It is connected to the separator 37 (Fig. 10). The first separator 37 is for separating the hydrogen chloride gas generated in the dissolving cylinders 31a, 31b, 31c from the decomposition gas slightly contained therein. The first separator 37 has a cooling coil 301 at the top. Then, the hydrogen chloride gas flowing through the pipe 78 is cooled when passing through the cooling coil 301, and is discharged to a lower portion of the first separator 37 located below the cooling coil 301. The released hydrogen chloride gas is further passed through a cooling coil 301, from above the first separator 37, to a second separator 38 having the same structure as the first separator via a pipe 79. Furthermore, the hydrogen chloride gas separated by the second separator 38 is the third separator 3 having the same structure as the first and second separators 37, 38. After being sent to 9 and completely separated from the decomposition gas by the third separator 39, it is sent to the lower part of the reactor 300 via the pipe 81. By arranging the plurality of separators 37, 38, and 39, the hydrogen chloride gas can be completely separated from the decomposition gas.

The reactor 300 has a stirring bar 300, and the blades 304 are attached to the stirring bar 300. A slaked lime tank 83 is connected to the upper part of the reactor 300. The slaked lime tank 83 has a heating cylinder 304 around the slaked lime for drying the slaked lime in the slaked lime tank 83. A lead screw 303 is provided below the slaked lime tank 83, and the lead screw 303 is rotated by a motor 304.

Further, a lead screw 309 is provided at the lower end of the reactor 303, and the lead screw 309 is rotated by a motor 310. The periphery of the lead screw 309 is heated by a heating cylinder 313 in order to dry and remove water generated by the reaction of the reactor. The calcium chloride generated by the reaction in the reactor 309 is stored in the salt calcium tank 312. In addition, temperature sensors S1, S2, and S3 are provided at appropriate positions in the height direction of the reactor 300, and the heat of reaction is detected by the temperature sensors S1, S2, and S3. The rotation of the motor 304 of the slaked lime tank 83 and the motor 310 of the discharge lead screw 309 of the reactor 300 is controlled by the reaction heat detection signal. In other words, the stirring rod 303 of the reactor 300 is constantly rotating, and when a large amount of hydrogen chloride gas enters the reactor 300, the reaction becomes active and a large amount of reaction heat is generated. When the highest-order temperature sensor S3 detects reaction heat of a certain level or more, the lead screw 303 of the slaked lime tank 83 is rotated so as to send a large amount of slaked lime. After that, the reaction proceeds and the heat of reaction decreases, the temperature decreases slightly, and the middle temperature sensor S 2 detects a certain range of temperature During the period, slaked lime will be supplied accordingly. Further, when the reaction slows down and the lowest temperature sensor S1 detects a predetermined temperature, it is determined that the reaction has ended, and the lead screw 309 for discharging the reactor 300 is generated by rotating the lead screw 309 for discharging. The calcium chloride is collected in a salt calcium tank 312. After the generated calcium chloride is recovered, when the reaction starts again, the temperature sensor S1 detects the start of the reaction, and rotates the lead screw 303 to put slaked lime from the slaked lime tank 83 into the reactor 300. As the temperature sensors S2 and S3 sequentially detect the feed and reaction heat, the supply of slaked lime is increased, and the slaked lime supply fee is reduced as the reaction heat decreases, and the above-described operation is repeated. .

It is generally said that hydrogen chloride gas does not react with a dry neutralizing agent without a solvent, but here, when hydrogen chloride gas is reacted with slaked lime, the water generated at that time becomes a solvent, and the neutralization reaction occurs. Facilitate. The reaction formula is as follows.

2 HC 1 + C a (OH) ₂ = C a C l ₂ + 2 H ₂ 0

In addition, a vacuum pump 314 is provided to remove water generated as steam in the reaction, and to draw hydrogen chloride gas into the reactor 300. In order to keep the suction load of the vacuum pump 314 constant, a relief valve 315 for inflow of air is provided on the inlet side of the vacuum pump 314. Further, in order to remove hydrogen chloride gas that did not react sufficiently in the reactor 300, a scrubber 317 for cleaning the reactor was provided.

Next, the off-gas processing device 34 will be described.

FIG. 11 is a diagram showing a schematic configuration of the off-gas processing device 34. As shown in FIG. As shown in FIG. 11, the offgas treatment device 34 has a casing 236. During operation of the oil plant, the casing 23 The inside of the casing 236 is heated to about 1200 ° C.

A plurality of ceramic prisms 238 and 238-238 are erected in the casing 236. The prism of this ceramic catalytically decomposes the off-gas flowing from the inlet 235 connected to the oil storage tanks 42, 43 in 1/1100 seconds to 210 seconds, and C 0 _2, NO _x, changing simple oxides such as H ₂ 0. At this time, the generated heat energy is guided to the first and second hot air generators 35 and 36 through the outlet 237.

The off-gas is an environmental hormone such as acetaldehyde which was not turned into oil by the condensers 37 and 38. In the present embodiment, the off-gas is collected in the oil storage tanks 42 and 43 and after being collected, these oil storage tanks 42 , 43 to the off-gas treatment device 34. The off-gas may be sent directly from the condensers 37 and 3'8 to the off-gas treatment device 34.

Next, the safety system and the deodorization system in the inclined pipe will be described. As shown in FIG. 20, a large number of temperature sensors S, S... S are provided in each dissolving tube of the dissolving section 31 and each inclined pipe of the dissolving section 32. Each of these sensors S is connected to a controller 511, and this controller 511 controls opening and closing of a valve 513 connected to a carbon dioxide gas cylinder 512. This carbon dioxide gas cylinder 5 12 is connected to a hot air circulation path P that sends hot air from the first and second hot air generating furnaces 35 and 36 into the melting section 31 and the decomposition section 32. Then, when the temperature sensor S detects an abnormal temperature such as an accident, the controller 511 opens the valve 513 and sends the carbon dioxide gas through the hot air circulation path Q to the melting section 31 and the decomposition section 3. Supply within 2. Thereby, the inside of the melting section 31 and the decomposition section 32 is cooled, and the operation of the oil conversion plant 30 is stopped.

A plastic deposition site A to be treated has a suction fan 5 1 4a The suction device 5 14 is disposed above. Then, air with an unusual odor particularly generated from the waste plastic is sucked by the suction device 514, sent to the hot air generating furnace 366, burned and deodorized.

The plastic flakes P pulverized by the crusher 515 are dried in a dryer 516 using warm air from a hot air generator 36, and the dried plastic flakes P are transferred to a hopper 4. Sent to 1. Here, when the plastic flakes P are dried with hot air in the dryer 5 16, an unpleasant odor may be filled in the vicinity. Therefore, the air in the dryer 5 16 with an unpleasant odor is sent to the hot-air generating furnace 35 for processing after the fine particles mixed into the air are removed by the cyclone 5 17 by the fan 5 16 a. You. These systems are expected to have a sufficient deodorizing effect.

In addition, air with an unpleasant odor may be decomposed in an off-gas processing section 34 for processing off-gas. That is, the air with an unpleasant odor is treated in the hot-air generators 35 and 36 or the off-gas treatment section 34.

In the above embodiment, the disassembly cylinders are provided in two stages. However, as shown in FIG. 12, after the second stage disassembly tube 48, the same structure as the second stage disassembly tube 48 is provided. A third-stage disassembly cylinder 210 inclined at the same angle is provided, and the temperature distribution is 350 to 400 ° C in the first-stage disassembly cylinder and 400 ° C in the second-stage disassembly cylinder. A melting section 200 set at 480 ° C. to 480 ° C. and in the third stage disassembly cylinder at 480 ° C. to 580 ° C. may be provided. By using three stages of decomposition cylinders in this way, the decomposition temperature distribution can be taken more gently and the decomposition time can be extended, so that it is possible to respond to changes in the decomposition conditions due to the specific gravity of the raw material plastic, etc. Secondary decomposition is guaranteed.

That is, the upper end side of the second-stage disassembly tube 48 is connected to the lower end of the third-stage disassembly tube 210 having the same inclination angle via the drop tube 218, and is extracted by the second-stage disassembly tube 48. The undecomposed foamed plastic and decomposition gas that did not It is fed into the third stage disassembly cylinder 210 via 8. The undecomposed foamy plastic and decomposition gas sent to the third-stage decomposition cylinder 210 are secondarily decomposed in the third-stage decomposition cylinder 210, and the second-decomposed decomposition gas is used for cleaning by the Arikari cleaning. The oil is cooled by the condenser 2 13 via the scrubber 2 16 and becomes oil equivalent to heavy oil A. This oil is collected in the oil storage tank 215 via the pipe 216. A blower 221 is connected to the third-stage decomposition tube 210, whereby the caro-hot air circulates from the top to the bottom of the decomposition tube while forming a reverse heat gradient. Note that the residue is collected in a sludge tinder 220 into which water has been injected through a sludge pipe 219. The cracked gas that has not been liquefied by the condenser 21'3 of the third stage disassembly cylinder 210 is sucked by the pump P, collected through the pipe 214, and collected in the oil storage tank 215. In the first and second stage decomposition cylinders 47 and 48, the secondly decomposed gas is extracted from the upper end and turned into oil. Decompose from heat 15 1 and 15 2. In the second-stage cracker, cracked gas equivalent to light oil, kerosene, and heavy oil components in the-part is obtained, and the remaining heavy oil-A equivalent components are decomposed in the third-stage cracker. It is also possible for the official to have more than four disassembly cylinders.

In the embodiment shown in FIG. 12, the melting portion 200 is formed in a vertical shape (vertical shape). That is, the first, second, and third melting cylinders 201, 202, and 203 are vertically connected via connecting portions 204 and 205, respectively, and are fed from the hopper 41. The melted plastic is sent to the right in the first melting cylinder 201, sent to the left in the second melting cylinder 202, sent to the right in the third melting cylinder, and 4 7 is supplied to the lower end. The lead screw 200 of the third melting cylinder 203 at the bottom is rotated by a motor 208, and the rotation of the motor 208 is controlled by the lead screw of the first melting cylinder 201 via the chain 209. Turn screw 206, and furthermore, this lead screw 2 The rotation of 06 causes the lead screw 2 12 of the second melting cylinder 202 to rotate through the gears G l and G 2. The hot air is drawn out from the lower side of the melting part 200 at a lower temperature by the blower 2 13, sent downward through the pipe 222, and circulated upward in the melting part.

In the embodiment shown in FIG. 21, the first to fourth melting cylinders 31a, 31b ... 31d are heated by the heat medium supplied from the heat medium heating device 600. Here, the heat medium refers to a liquid heat medium, for example, various heat medium oils are used. This heat medium is heated to a predetermined temperature by the heat medium heating device 600 and supplied to the heat medium space 135 of the melting cylinder 31 via the heat medium pipe 601. The heat medium space 135 is formed between the inner cylinder 131 and the outer box 13'6 in the same manner as the hot air space 135 described above. The heat medium is circulated by the circulation pump 62 so that the heat medium flows from the downstream side to the upstream side in the heat medium space 135 '. The temperature in the first melting cylinder 31a is 190 to 200, the temperature in the second melting cylinder 31b is 210 to 230 ° C, and the temperature in the third melting cylinder 31c is 230 ° C. C-260. First, the inside of the fourth melting cylinder 31 d is controlled at 300 to 330 ° C., respectively, in the same manner as in the case of the above-described heating with hot air.

By using a heat medium instead of hot air, it is possible to a) significantly improve the heat transfer efficiency, and b) dissolve even when the plant is stopped because the heat medium is harder to cool compared to hot air. When the plant is started up, it is possible to start up the plant in a short time because the temperature inside the cylinder 31 does not drop.c) Even if the inner cylinder 13 1 of the melting cylinder 31 is damaged, a fire may occur. The occurrence can be prevented.

Since the operating temperature of the heat medium is generally 350 ° C. or lower, the heat medium is used only for heating the melting cylinder 31.However, by selecting a more appropriate heat medium, the decomposition cylinder 47, It is also possible to use a heat medium for heating of _c. Also, depending on the operating temperature of the heat medium used, a low temperature Only the melting cylinder 31 (for example, the first, second and third 'melting cylinders 31a, 31b and 31c) to be trolled may be heated by the heat medium.

In the embodiment shown in FIG. 13, the lower part of the fourth melting cylinder 31 d and the lower part of the first stage disassembling cylinder 47 are joined by a joint 500, and the foam melted through the joint 500 Plastic is supplied to the lower end of the inner cylinder 255 in the first stage disassembly cylinder 47. The joint 500 is supplied with vegetable or animal edible oil stored in the tank 502 or waste oil after use thereof. The primary and secondary components are decomposed in the disassembly tube. This makes it possible to recover the reformed oil by a chemical decomposition reaction.

In general, as shown in Fig. 14, plastics such as polyethylene, polypropylene, polystyrene, ABS resin, and acrylic resin are thermally decomposed and 90% of the oil is collected as product oil. ° / ₀ ) and is treated by the off-gas treatment device 34, and the carbide (2 to 3%) is collected in the residue tank 40 as a residue. Polyvinyl chloride is neutralized with slaked lime to make about 58% of calcium chloride and about 42% is pyrolyzed, but about 30% of oil is collected and collected.

The Japanese patent application (No. 2002-017650), including the specification, claims, drawings, and abstract filed on January 25, 2002, and October 2010 The entire disclosure of the Japanese patent application (No. 2002-301895), including the specification, claims, drawings and abstract filed on March 16, 2005, is incorporated herein by reference in its entirety. .

Further, the present invention is not limited to the above embodiment. The above embodiment is an exemplification, and has substantially the same configuration as the technical idea described in the claims of the present invention, and does not provide any similar effect. Are also included in the technical scope of the present invention. [Industrial applicability]

INDUSTRIAL APPLICABILITY As described above, the plastic oiling method and the oiling plant according to the present invention are useful as an oiling method and an oiling brand for collecting oil from waste plastics.

Claims

The scope of the claims

1. A melting step in which the plastic is heated and melted to form a foamed plastic;

A decomposition step of removing the foamed plastic, heating and depolymerizing, and then cooling to produce oil;

A method for liquefying a plastic, comprising:

2. The method according to claim 1, wherein

In the dissolving step, the foamed plastic is pulled up diagonally upward and taken out.

3. The method according to claim 1, wherein

In the disassembling step, the plasticizing method is characterized in that the foamed plastic is pulled out obliquely upward at an angle of 25 to 30 ° with respect to the horizontal and taken out.

4. In the method for liquefying plastic according to claim 2 or 3, in the decomposition step, the foamed plastic is heated while being pulled obliquely upward, and the foamed plastic is positioned more upwardly. A plastic oiling method characterized by heating at a high temperature.

5. The method according to claim 1, wherein

In the melting step, the plastic is melted in a melting section formed by a plurality of melting cylinders having different temperature distributions.

6. The method according to claim 1, wherein

In the dissolving step, food oil, animal oil or mineral oil is added to the dissolved plastic to form a foamed plastic composed of a mixture of the plastic and the food oil, the animal oil or the mineral oil,

In the decomposition step, the foamed plastic is taken out, heated and de-polymerized, and then cooled to produce oil.

7. The method according to claim 1, wherein

In the decomposing step, the foamed plastic is taken out and heated in a decomposing section formed by a plurality of decomposing cylinders having different temperature distributions and heated.

8. The method according to claim 1, wherein

A hydrogen chloride gas processing step of separating hydrogen chloride and gas generated when the plastic is melted in the melting step from other decomposed gases and then reacting with slaked lime to recover as calcium chloride. How to make plastic oil.

9. The method according to claim 1, wherein

A method for liquefying plastics, which further comprises an off-gas treatment step of subjecting the off-gas not liquefied in the decomposition step to catalytic decomposition with high-temperature ceramics for treatment.

10. Heat and melt the plastic to form a foamy plastic. Dissolving part

A decomposition unit that takes out the foamed plastic, heats it, depolymerizes it, and then cools it to produce oil;

An oil conversion plant comprising:

11. 1 In the oil conversion plant according to claim 10,

An oiling blunt, wherein the disassembling unit includes an extracting means for extracting the foamed plastic by diagonally pulling it upward.

1 2. In the oil conversion plant according to claim 10,

An oily blunt characterized in that the disassembling section is provided with a take-out means for taking up and taking out the foamed plastic obliquely upward at an angle of 25 to 30 ° with respect to the horizontal.

13. The oil conversion plant according to claim 11, wherein the decomposition section heats the foamed plastic while pulling the foamed plastic diagonally upward, and the higher the temperature, the higher the foamed plastic is located. 13. An oily blunt characterized by comprising a heating means for heating by heating.

14. The oil conversion plant according to claim 10, wherein:

An oil conversion plant, wherein the melting section is formed by a plurality of melting cylinders having different temperature distributions.

15. In the oil conversion plant according to claim 10,

An oil conversion plant comprising an oil injection means for injecting food oil, animal oil, or mineral oil into a joint between the melting section and the decomposition section.

16. In the oil conversion plant according to claim 10,

An oil conversion plant, wherein the decomposition section is formed by a plurality of inclined decomposition cylinders having different temperature distributions.

17. In the oil conversion plant according to claim 10,

A dechlorination device for treating hydrogen chloride gas generated in the dissolving section,

The dechlorination apparatus is configured to include a separator for decomposing hydrogen chloride gas and other decomposition gases, and a reactor that reacts the hydrogen chloride gas separated by the separator with slaked lime to form calcium chloride. An oil conversion plant characterized by the following.

18. The oil conversion plant according to claim 10, wherein:

An oil processing plant, further comprising an off-gas treatment device for catalytically decomposing and treating off-gas not produced as oil after cooling in the decomposition section with a high-temperature ceramics.

1 9. In the oil conversion plant according to claim 16,

An oily blunt characterized in that a decomposition gas generated by depolymerizing the plastic in each of the decomposition cylinders provided in multiple stages is cooled and turned into oil.

20. In the oil conversion plant according to claim 16,

An oiling plant comprising a superheat for further depolymerizing the depolymerized plastic in at least a part of the decomposition tube.

2 1. In the oil conversion plant according to claim 16,

An oil conversion plant, wherein the decomposition tube is formed so that the heating temperature gradually increases from below to above. '

22. In the oil conversion plant according to claim 16,

An oil conversion plant, wherein a residue recovery means is provided at an upper end of the final stage of the decomposition cylinder among the multistage decomposition cylinders.

2 3. In the oil conversion plant according to claim 22,

An oil conversion plant, wherein the residue recovery means is formed by a cylinder having an upper opening located at an upper end position of the final stage decomposition cylinder and a lower opening located in an inert gas atmosphere heavier than air.

24. In the oil conversion plant according to claim 10,

An oil conversion plant, further comprising: a hopper for storing the plastic and supplying the plastic to the melting section, wherein the hopper includes a lead screw having spiral blades.

25. In the oil conversion plant according to claim 24,

An oil-forming plant, further comprising: a non-heating portion formed by a non-heated region having a predetermined length between the hopper and the melting portion.

26. In the oil conversion plant according to claim 14,

The plurality of melting cylinders are spiral blades for conveying the plastic. It has a lead screw with a root,

The pitch of the blades of the lead screw of the melting cylinder positioned at the top of the plurality of melting cylinders is formed to be larger than the pitch of the blades of the lead starry of the other melting cylinders. Oiling plant.

27. In the oil conversion plant according to claim 10,

An inner cylinder, an outer cylinder formed on an outer periphery of the inner cylinder, a hot air space formed between the inner cylinder and the outer cylinder and circulating hot air; And a temperature sensor for detecting a temperature of the melting section or the decomposition section.

An oil conversion plant, further comprising: a carbon dioxide gas supply device for feeding carbon dioxide gas into the hot air space when the temperature sensor detects an abnormal temperature that is equal to or higher than a predetermined temperature.

28. In the oil conversion plant according to claim 10,

The dissolving unit and the disassembling unit include an inner cylinder, an outer cylinder formed on the outer periphery of the inner cylinder, and a hot air space formed between the inner cylinder and the outer cylinder and circulating hot air. Formed in preparation for

A hot-air generator for generating hot air by combustion for supplying to the hot-air space,

A drying device for drying the plastic supplied to the melting furnace,

An oil conversion plant, wherein the air in the drying device is supplied to the hot-air generating device and deodorized by combustion.

29. In the oil conversion plant according to claim 18,

A drying device for drying the plastic supplied to the melting section, further comprising:

An oil conversion plant, wherein the air in the drying device is supplied to the off-gas processing device and catalytically decomposed by high-temperature ceramics to deodorize.

30. In the oil conversion plant according to claim 14,

An expandable and contractible cylinder is used for a part of the dissolving cylinder, and the expandable and contractible cylinder is an inner cylinder, which is disposed on the outer periphery of the inner cylinder, one end is fixed to the inner cylinder, and the other end is the other end. A bellows slidable with respect to the inner cylinder; and an outer cylinder fixed to the other end of the bellows and housing the inner cylinder slidably therein. Oil conversion plant.

31. In the oil conversion plant according to claim 10,

The dissolving unit includes: an inner cylinder; an outer cylinder formed on the outer periphery of the inner cylinder; and a heat medium space formed between the inner cylinder and the outer cylinder, through which a liquid heat medium is circulated. Formed

A heat medium supply device that supplies a liquid heat medium to the heat medium space,

An oil conversion plant, further comprising: