JP2009167274A - Oil-forming/reduction device for waste plastic - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve efficiency of oil-forming/reduction by reducing the whole of waste plastic to be subjected to oil-forming/reduction processing. <P>SOLUTION: The oil-forming/reduction device includes a decomposition feed pipe 21 and a second hot air generating furnace 24 generating hot air to be fed to a hot air passage 21b in the decomposition feed pipe 21. In the decomposition feed pipe 21, the helical hot air passage 21b separated from outside air by a hot air passage cover 26 is provided, and a temperature gradient wherein temperature rises gradually from one side, to which waste plastic material is supplied from a melting feed pipe 13, to the other side so that the waste plastic material fed from the melting feed pipe 13 is heated to be thermally decomposed, and then, decomposition gas is separated. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a waste plastic oil reduction apparatus. More specifically, the present invention relates to a technique for thermally decomposing waste plastics to perform oil reduction treatment.

  As a conventional technique for thermally decomposing waste plastics for oil reduction treatment, for example, there is a thermal decomposition apparatus for polymer waste (Patent Document 1). This thermal decomposition apparatus has a feed pipe having a feed screw connected in a V-shape with a large scissor angle and an inclined pipe having a feed screw inside, and polymer waste inside the feed pipe. It is melted by the heat of the first hot stove and stays in the V-shaped part, and further, the polymer melt is primarily decomposed by the heat of the second hot stove while being sent upward with a feed screw inside the inclined tube. The cracked gas generated by the above is secondarily decomposed by the heat of the third hot stove.

JP 2000-1677

  Here, in order to extract the produced oil by thermally decomposing plastic, in general, the plastic reaches the melting point and dissolves into a liquid state, from the dissolved state to the first gasified state. It is necessary to produce a secondary cracked gas and cool it by changing the state in the order of secondary cracking, which is a lightened state by further applying heat to the primary cracked gas → the primary cracked gas. . If too much heat is applied to the plastic, it will pass through the state of secondary cracked gas, resulting in a state of tertiary cracking (also referred to as an off-gas state) that becomes a combustible gas, or a carbonized state that will be carbonized.

  That is, in the extraction of the produced oil by the thermal decomposition of the plastic, the produced oil cannot be extracted because the plastic does not dissolve or does not gasify even if the temperature is too low. On the other hand, when the temperature is too high, an off-gas state or a carbonized state is obtained, so that the produced oil cannot be extracted also in this case.

  However, in the thermal decomposition apparatus of Patent Document 1, unevenness occurs in the heating of the feed pipe and the inclined pipe by the heat of the hot stove, and a high temperature portion and a low temperature portion are locally formed. In this case, in the low-temperature part, a part of the polymer waste remains undissolved and remains as an undissolved part, and it may become clogged or solidified in the feed pipe or the inclined pipe of the pyrolysis device and clog the feed pipe or the inclined pipe. is there. For this reason, it is difficult to say that the operation of the apparatus is stable and reliable. Furthermore, there is an oil that is originally decomposable but remains in the undissolved portion without being decomposed, and the oil obtained as a result of the reduction treatment by thermal decomposition with respect to the amount of polymer waste to be put into the apparatus The amount of will decrease. For this reason, it is hard to say that the efficiency of oil reduction is high.

  Moreover, if the temperature of the hot air that heats the feed pipe or the inclined pipe is increased to prevent the formation of a local low temperature portion, the temperature of the local high temperature portion becomes extremely high, and in this portion, the dissolved state and the primary cracked gas From the state, it passes through the state of the secondary cracked gas to become an off-gas state or a carbonized state, and in this case, it cannot be oiled.

  Then, an object of this invention is to provide the waste plastic oil reduction apparatus which can improve the efficiency of oil reduction by reducing all the waste plastics of oil reduction reduction process object. It is another object of the present invention to provide a highly reliable waste plastic oil reduction apparatus that can operate stably and continuously without stagnation or solidification of undissolved components in the apparatus. .

  In order to achieve this object, the waste plastic oil reduction apparatus according to claim 1 is a hot air passage formed around the screw conveyor while the waste plastic raw material in a dissolved state is sent by the screw conveyor separated from the outside air. In the oil reduction and reduction device that continuously performs primary decomposition and secondary decomposition by the heat of the hot gas guided to the hot gas, a spiral barrier is arranged in the hot air passage, and the hot gas spirals along the outer peripheral surface of the screw conveyor. I try to pass.

  Moreover, the waste plastic oil reduction apparatus according to claim 2 has a melting feed pipe that has a spiral hot air passage around which is separated from the outside air by a cover that covers the outside, and melts the waste plastic raw material by heating, The side where the waste plastic raw material is introduced from the melting feed pipe by injecting hot air into the hot air passage from the side where the waste plastic raw material is discharged while having a spiral hot air passage which is separated from the outside air by a cover covering the outside A decomposition feed pipe that separates the cracked gas by heating and thermally decomposing the waste plastic raw material supplied from the dissolution feed pipe by forming a temperature gradient that gradually increases in temperature from the Hot air generation that generates hot air to be supplied to the hot air passage of the feed pipe and the hot air passage of the feed pipe for decomposition So that and a furnace.

  Therefore, according to the waste plastic oil reduction apparatus according to the first and second aspects, the hot air passage is spirally provided around the screw conveyor and the feed pipe, and the hot air is allowed to pass through the spiral hot air passage. Therefore, the feed pipe can be heated without causing temperature unevenness in the circumferential direction.

  The invention described in claim 3 is the waste plastic oil reduction apparatus according to claim 2, further comprising a nitrogen gas generator for generating nitrogen gas injected into the dissolution feed pipe and the decomposition feed pipe. I am doing so. In this case, since the nitrogen gas is injected into the dissolution feed pipe and the decomposition feed pipe, the space can be kept in a low oxygen state.

  Furthermore, the invention described in claim 4 is the waste plastic oil reduction apparatus according to claim 2 or 3, wherein the end on the opposite side to the end on the side where the waste plastic raw material is introduced from the melting feed pipe is provided. The decomposition feed pipe is installed so as to be higher. In this case, since the one end of the cracking feed pipe is set higher than the other end, the cracked gas generated by separation from the waste plastic by thermal decomposition is naturally generated from the cracking feed pipe. To be discharged.

  According to the first and second aspects of the invention, since the feed pipe can be heated without causing temperature unevenness in the circumferential direction, heat is uniformly applied to the entire waste plastic put into the apparatus for gasification. Thus, the efficiency of oil reduction can be improved. Furthermore, by performing the oil reduction treatment completely, it is possible to avoid the situation where undissolved components are stagnated or solidified in the device and cause trouble in operation, so that the stability and reliability of the device can be improved. Is possible.

  According to the invention described in claim 3, since the inside of the dissolving feed pipe and the inside of the decomposing feed pipe can be kept in a low oxygen state, even if static electricity is generated, It is possible to prevent ignition and maintain safety during operation and improve stability and reliability of the apparatus.

  Furthermore, according to the invention described in claim 4, since the cracked gas generated by separating from the waste plastic by pyrolysis is naturally discharged from the cracking feed pipe, the cracked gas is sucked from the cracking feed pipe. Therefore, the configuration of the apparatus can be simplified and the maintenance cost can be reduced.

  Hereinafter, the configuration of the present invention will be described in detail based on the best mode shown in the drawings.

  FIG. 1 shows an example of an embodiment of the waste plastic oil reduction apparatus of the present invention. The waste plastic oil reduction apparatus of the present invention is a method for supplying hot gas introduced into the hot air passage 21b formed around the screw conveyor 21 while the waste plastic raw material in a dissolved state is sent by the screw conveyor 21 in a state separated from the outside air. In an oil reduction and reduction apparatus that continuously performs primary decomposition and secondary decomposition by heat, a spiral barrier 21a is disposed in the hot air passage 21b, and the hot gas passes spirally along the outer peripheral surface of the screw conveyor 21. It is.

  And the waste plastic oil-reduction apparatus 1 of this embodiment has the raw material input part 2, the melt | dissolution part 12, and the decomposition | disassembly part 20 roughly divided.

  Specifically, the waste plastic oil reduction apparatus 1 of the present embodiment has a spiral hot air passage 13b that is separated from the outside air by a hot air passage cover 18 that covers the outside and melts the waste plastic raw material by heating. By injecting hot air into the hot air passage 21b from the side from which the waste plastic raw material is discharged, while having a spiral hot air passage 21b separated from the outside air by a melting feed pipe 13 and a hot air passage cover 26 covering the outside The waste plastic raw material supplied from the melting feed pipe 13 is heated and thermally decomposed by forming a temperature gradient in which the temperature gradually increases from the side where the waste plastic raw material is introduced from the melting feed pipe 13 toward the opposite side. Of the cracking feed pipe 21 for separating the cracked gas and the melting feed pipe 13 through hot air Comprising a first hot air generator furnace 16 for generating hot air to be supplied to 13b, and a second hot air generator furnace 24 for generating hot air to be supplied to the hot air passage 21b of the cracking feed pipe 21.

  The raw material charging unit 2 includes a raw material charging hopper 3, an extruder 4 that communicates with the raw material charging hopper 3, a charging feed pipe 6 that communicates with the extruder 4 and includes a feed screw 7 therein, and a feed screw 7. And a first motor 9 that is driven to rotate.

  The raw material charging hopper 3 is for continuously supplying the waste plastic raw material to be subjected to the oil reduction treatment to the waste plastic oil reduction device 1. Specifically, the raw material charging hopper 3 of the present embodiment has a funnel-shaped raw material storage part 3a, and an extruder 4 that communicates waste plastic raw material stored in the raw material storage part 3a with the opening 3b at the lower end. To supply.

  The extruder 4 is for heating and dissolving the waste plastic raw material. Specifically, the extruder 4 heats, melts and presses the waste plastic raw material supplied from the raw material charging hopper 3 by an internal screw and a heating cylinder (barrel) surrounding the screw, and pushes it out to the charging feed pipe 6. . The heating temperature in the extruder 4 is a temperature at which the temperature of the waste plastic raw material is increased and a part of the raw material starts to melt in order to more efficiently heat and dissolve the waste plastic raw material in the melting feed pipe 13. Adjusted to

  In addition, it is preferable to provide an exhaust port 38 in the heating cylinder of the extruder 4 and a chlorine gas processing device 39 connected to the exhaust port 38 in order to process chlorine gas generated from the waste plastic raw material by heating. Thereby, it can prevent that chlorine gas flows in into the processing mechanism after the extruder 4 and the inside of an apparatus corrodes. .

  The feeding feed pipe 6 is for conveying the waste plastic raw material while heating from the extruder 4 toward the melting feed pipe 13 of the melting section 12.

  Therefore, the feeding feed pipe 6 is connected to and communicated with the discharge port of the extruder 4 at one end (raw material charging side end), and is dissolved near the other end (raw material discharge side end). The feed pipe 13 and the connection pipe 8 are connected to communicate with each other. The length and diameter of the feeding feed pipe 6 are not limited to specific dimensions, and are appropriately adjusted according to the transport of the waste plastic raw material from the extruder 4 to the melting feed pipe 13.

  The feed pipe 6 for feeding conveys the waste plastic raw material in a molten state supplied from the extruder 4 toward the raw material discharge side end opposite to the extruder 4 by the internal feed screw 7. In addition, a plurality of heaters are disposed in the axial direction on the outer periphery of the feeding feed pipe 6, and the feeding feed pipe 6 transports the waste plastic raw material melted by the extruder 4 in a dissolved state.

  The feed screw 7 is rotationally driven by a first motor 9 provided at the raw material discharge side end. The feeding feed pipe 6 and the feed screw 7 are made of stainless steel.

  Here, in order to prevent the waste plastic raw material from adhering to the screw and to prevent the screw from coming off with the waste plastic raw material being bitten, oil is injected into the feed pipe 6 as a lubricant for the waste plastic raw material. Is preferred. In addition, as this oil, you may make it use the production | generation oil by which the waste plastic oil reduction apparatus 1 performed the oil reduction process, and you may make it use another oil. Further, when oil is injected into the feed pipe 6 for injection, it is preferable to input the oil after heating the oil slightly higher than the heating temperature of the waste plastic raw material by the extruder 4.

  Next, the melting part 12 includes a melting feed pipe 13 provided with a feed screw 14 therein, a second motor 15 that rotationally drives the feed screw 14, a hot air passage cover 18 that covers the outside of the feed pipe 13, A first hot air generating furnace 16 having a burner 17 for generating hot air supplied to the hot air passage of the feed pipe 13 and an exhaust blower 19 provided in the hot air passage of the feed pipe 13 are provided.

  The melting feed pipe 13 conveys the waste plastic raw material in a dissolved state supplied from the feeding feed pipe 6 toward the decomposition feed pipe 21 of the decomposition unit 20 while further heating it to a better and complete melting state. Is for.

  For this reason, the melting feed pipe 13 is connected to and communicated with the vicinity of the raw material discharge side end of the feed pipe 6 through the connecting pipe 8 in the vicinity of one end (raw material input side end), and the other end. In the vicinity of the end portion (raw material discharge side end portion), the decomposition feed pipe 21 and the connection pipe 28 are connected to communicate with each other. Note that the length and diameter of the melting feed pipe 13 are not limited to specific dimensions, and are adapted to the specifications required to completely dissolve the waste plastic raw material supplied from the feeding feed pipe 6. Adjust as appropriate.

  The melting feed pipe 13 is heated while transporting the waste plastic in a molten state supplied from the feeding feed pipe 6 toward the raw material discharge side end opposite to the connection pipe 8 by the internal feed screw 14. .

  The feed screw 14 is rotationally driven by a second motor 15 provided at the raw material charging side end. The melting feed pipe 13 and the feed screw 14 are made of stainless steel.

  On the outer periphery of the melting feed pipe 13, spiral fins 13a are provided so as to wrap around the pipe except for the vicinity of both ends.

  A hot air passage cover 18 is attached to the melting feed pipe 13 so as to surround the spiral fins 13 a provided on the outer periphery. In addition, it is preferable that one or both of the inner peripheral surface and the outer peripheral surface of the hot air passage cover 18 are covered with a heat insulating material such as glass wool.

  A spiral hot air passage 13b that is separated from the outside air is formed on the outer periphery of the melting feed pipe 13 by the spiral fin 13a and the hot air passage cover 18 surrounding the fin 13a.

  Further, the hot air passage cover 18 is provided with a hot air blowing port 18a at a position near the raw material discharge side end portion of the melting feed pipe 13 and exhausted at a position near the raw material input side end portion of the melting feed pipe 13. An exhaust port 18b through which the blower 19 communicates is provided. And the 1st hot-air generation furnace 16 provided with the burner 17 is connected and connected to the blowing inlet 18a.

  With the above configuration, the hot air heated by the burner 17 provided in the first hot air generating furnace 16 by the operation of the exhaust blower 19 is provided in the hot air passage 13b on the raw material discharge side end portion side of the melting feed pipe 13. It passes from the blow-in port 18a toward the exhaust port 18b on the raw material charging side end portion side. Thus, a temperature gradient is formed in the melting feed pipe 13 such that the temperature increases from the raw material input side end to the raw material discharge side end.

  Next, the decomposition unit 20 includes a decomposition feed pipe 21 having a feed screw 22 therein, a third motor 23 that rotationally drives the feed screw 22, a hot air passage cover 26 that covers the outside of the feed pipe 21, A second hot air generating furnace 24 having a burner 25 for generating hot air supplied to the hot air passage of the feed pipe 21, an exhaust blower 27 provided in the hot air passage of the feed pipe 21, and a residue tank 30 communicating with the feed pipe 21. With.

  The decomposition feed pipe 21 is for heating the waste plastic in a dissolved state supplied from the dissolution feed pipe 13 to decompose it into decomposition gas and residue.

  For this reason, the decomposition feed pipe 21 is connected to and communicated with the vicinity of the raw material discharge side end portion of the dissolution feed pipe 13 through the connection pipe 28 in the vicinity of one end portion (raw material input side end portion). It should be noted that the length and diameter of the decomposition feed pipe 21 are not limited to specific dimensions, and are required to completely decompose the waste plastic in a dissolved state supplied from the dissolution feed pipe 13. It adjusts suitably together.

  The decomposition feed pipe 21 transports the molten waste plastic supplied from the melting feed pipe 13 toward the end opposite to the connecting pipe 28 (raw material discharge side end) by the internal feed screw 22. Heat while.

  The feed screw 22 is rotationally driven by a third motor 23 provided at the raw material discharge side end. The decomposition feed pipe 21 and the feed screw 22 are made of stainless steel.

  On the outer periphery of the disassembling feed pipe 21, spiral fins 21a are provided so as to wrap around the pipe except for the vicinity of both ends. The pitch of the spiral fins 21a is adjusted so that the entire disassembling feed pipe 21 can be heated uniformly. Specifically, for example, it can be considered to be about 10 cm to 30 cm.

  In addition, a hot air passage cover 26 is attached to the disassembly feed pipe 21 so as to surround the spiral fins 21 a provided on the outer periphery. A spiral hot air passage 21b is formed on the outer periphery of the decomposition feed pipe 21 by the spiral fin 21a and the hot air passage cover 26 surrounding the fin 21a. The distance between the outer peripheral surface of the decomposition feed pipe 21 and the inner peripheral surface of the hot air passage cover 26 and the height of the spiral fin 21a heat the entire decomposition feed pipe 21 evenly by passing hot air through the hot air passage 21b. The top of the spiral fin 21a and the inner peripheral surface of the hot air passage cover 26 are adjusted so as not to be too far apart. Specifically, for example, the distance between the outer peripheral surface of the decomposition feed pipe 21 and the inner peripheral surface of the hot air passage cover 26 is set to about 5 cm to 10 cm, and the apex of the spiral fin 21 a and the inner peripheral surface of the hot air passage cover 26 are It is conceivable to set the distance of about 0.1 cm to 0.3 cm. In addition, it is preferable that one or both of the inner peripheral surface and the outer peripheral surface of the hot air passage cover 26 is covered with a heat insulating material such as glass wool.

  The hot air passage cover 26 is provided with a hot air inlet 26a at a position near the raw material discharge side end of the decomposition feed pipe 21 and exhausted at a position near the raw material input side end of the decomposition feed pipe 21. An exhaust port 26b through which the blower 27 communicates is provided. And the 2nd hot-air generation furnace 24 provided with the burner 25 is connected and connected to the blowing inlet 26a.

  With the above configuration, the hot air heated by the burner 25 provided in the second hot air generating furnace 24 by the operation of the exhaust blower 27 is placed in the hot air passage 21b on the raw material discharge side end side of the decomposition feed pipe 21. It passes from the blow-in port 26a toward the exhaust port 26b on the raw material charging side end portion side. As a result, a temperature gradient is formed in the decomposition feed pipe 21 such that the temperature increases from the raw material input side end to the raw material discharge side end.

  In addition, a residue discharge port 21d is provided at the lower part of the raw material discharge side end of the decomposition feed pipe 21. The decomposition feed pipe 21 discharges the residue separated from the decomposition gas by heating the waste plastic in the decomposition feed pipe 21 from the residue discharge port 21d. Specifically, the residue is a foreign matter such as an inorganic material or a metal piece that is not thermally decomposed contained in the waste plastic raw material, or a carbide.

  A residue discharge pipe 29 is connected to the residue discharge port 21d so as to communicate with it, and the lower end of the residue discharge pipe 29 opens into the water of the residue tank 30 to form a water-sealed structure. Residues generated along with the oil reduction treatment by the waste plastic oil reduction device 1 are stored in the residue tank 30.

  Further, a gas outlet 21c is provided at the upper part of the raw material discharge side end of the decomposition feed pipe 21. The cracking feed pipe 21 discharges cracked gas generated as a result of the waste plastic being heated and thermally decomposed in the cracking feed pipe 21 from the gas outlet 21c.

  In the present embodiment, in order to allow the cracked gas to be naturally discharged from the cracking feed pipe 21, the cracking feed pipe 21 is higher at the raw material discharge side end than the raw material input side end. Installed. As a result, the light decomposition gas, which is a product of thermal decomposition of waste plastic, separates from the residue and rises to the higher side, and is naturally discharged from the gas outlet 21c on the raw material discharge side end. The

  Further, the waste plastic oil reduction apparatus 1 of the present invention is separated from the outside air by connecting the feed pipe 6 for connection, the connection pipe 8, the feed pipe 13 for dissolution, the connection pipe 28, and the feed pipe 21 for decomposition. Forming a space.

  And the waste plastic oil reduction apparatus 1 of this embodiment heats the nitrogen gas generated with the nitrogen gas generator 10 with the nitrogen gas heating apparatus 11, and injects from the feed pipe 6 for injection | throwing-in. As a result, according to the waste plastic oil reduction apparatus 1, the inside of the feed pipe 6 for injection and the inside of the feed pipe 13 for dissolution and the feed pipe 21 for decomposition forming a space communicating with this and separated from the outside air. Since it can be filled with nitrogen gas and kept in a low oxygen state, even if static electricity is generated, the gas in these feed pipes 6, 13 and 21 is prevented from igniting and is safe during operation Can keep. In addition, it can be considered that the heating temperature of the nitrogen gas by the nitrogen gas heating device 11 is in a range of about 5 ° C. to 40 ° C., for example.

  Next, a configuration for liquefying the cracked gas will be described.

  A gas feed pipe 31a is connected to the gas outlet 21c of the decomposition feed pipe 21 so as to communicate therewith. The cracked gas discharged from the gas outlet 21c is sent to the reactor 32 through the gas feed pipe 31a.

  The reactor 32 neutralizes hydrogen chloride gas contained in the cracked gas with slaked lime. The reactor 32 is connected so that the gas feed pipe 31b communicates. The cracked gas discharged from the reactor 32 after being neutralized is sent to a residual chlorine neutralizer (also called a scrubber) 33 through a gas feed pipe 31b.

  The residual chlorine neutralizer 33 neutralizes the residual chlorine content of the cracked gas by aqueous alkaline showering and removes the chlorine content in the cracked gas. The cracked gas is liquefied or oiled by this treatment.

  The residual chlorine neutralizer 33 is connected so that an oil feed pipe 34a is in communication. The liquid product oil that has been neutralized and discharged from the residual chlorine neutralization device 33 is sent to the catalyst device 35 through an oil feed pipe 34a.

Further, the off-gas decomposition apparatus 5 is connected to the residual chlorine neutralization apparatus 33 so as to communicate therewith. The off-gas decomposition apparatus 5 is for catalytically decomposing off-gas generated during the oil reduction treatment of the waste plastic raw material. Specifically, the off-gas decomposition apparatus 5 has a ceramic plate and a burner inside. Then, catalytic cracking is performed by blowing off gas, which has not been liquefied by the treatment in the residual chlorine neutralizer 33, to a ceramic plate heated to about 1200 ° C. by a burner. Note that the off-gas blown to the heated ceramic plate changes to simple oxides such as carbon dioxide (CO ₂ ), water (H ₂ O), and nitrogen oxide (NOx).

  The catalyst device 35 has a heater and a granular zeolite catalyst, and removes impurities by passing through a filtration tank in which the zeolite catalyst heated by the heater is stored, thereby purifying the produced oil. By heating the zeolite catalyst and keeping it at a high temperature, it is possible to prevent the product oil from solidifying and clogging the catalyst.

  An oil feed pipe 34b is connected to the catalyst device 35 so as to communicate therewith. The product oil that is refined and discharged from the catalyst device 35 is sent to a product oil distillation separation device (also referred to as a separator) 36 through an oil feed pipe 34b.

  The produced oil distillation separation device 36 distills the produced oil into light oil, kerosene equivalent, and heavy oil equivalent. The oil separated by distillation is sent to the oil storage tank 37 through the oil feed pipe 34c and stored.

  Operation | movement of the waste plastic oil-reduction apparatus 1 mentioned above is demonstrated below.

  In the oil reduction treatment by the waste plastic oil reduction apparatus 1 of the present invention, first, the waste plastic raw material is supplied to the extruder 4 through the raw material charging hopper 3. In addition, the supply of the waste plastic raw material to the raw material charging hopper 3 may be appropriately performed manually or may be performed using, for example, a quantitative supply device. The waste plastic raw material used in the present invention is subjected to a pulverization process and a drying process in advance before being input to the raw material input hopper 3. On the other hand, in the present invention, complicated separation processing and foreign matter removal processing are not required for the supplied raw material.

  Specific examples of the waste plastic raw material supplied to the waste plastic oil reduction apparatus of the present invention include industrial waste plastics such as polyethylene, polypropylene, and polystyrene, except for so-called thermosetting plastics such as melamine resins and epoxy resins. And industrial and general waste plastics such as ABS resin, vinyl chloride and polyethylene terephthalate (also referred to as PET).

  The extruder 4 heats, melts and pressurizes the supplied waste plastic raw material, and pushes it out to the feeding feed pipe 6.

  The feeding feed pipe 6 conveys the supplied waste plastic raw material in a melted state while heating it from the end on the extruder 4 side to the connecting pipe 8 on the opposite end, and feeds it through the connecting pipe 8 for melting. Put into the pipe 13.

  During the oil reduction treatment, high-temperature nitrogen gas is injected into the feed pipe 6 by the operation of the nitrogen gas generator 10 and the nitrogen gas heating device 11. As a result, the inside of the feeding feed pipe 6, the melting feed pipe 13 and the decomposition feed pipe 21 are kept in a low oxygen state.

  The peripheral wall of the melting feed pipe 13 is heated by the hot air passing through the hot air passage 13b by the operation of the burner 17 and the exhaust blower 19, and the waste plastic raw material is completely heated by being stirred while being conveyed by the feed screw 14. Dissolve.

  Then, the melting feed pipe 13 puts the completely dissolved waste plastic into the decomposition feed pipe 21 through the connecting pipe 28.

  The peripheral wall of the decomposition feed pipe 21 is heated by the hot air passing through the hot air passage 21b by the operation of the burner 25 and the exhaust blower 27, and the waste plastic is heated while being conveyed by the feed screw 22 to decompose gas and residues. Disassembled into At this time, the decomposition feed pipe 21 is formed with a temperature gradient in which the temperature increases from the raw material input side end to the raw material discharge side end, so that a plurality of types of plastics having different gasification temperatures are discarded. Even if it is put into the plastic oil reduction unit 1 at a time, the temperature becomes suitable for gasification for each kind of plastics while moving in the feed pipe 21 for decomposition, and all of the waste plastics that have been put in are oiled. Can be reduced.

  The cracked gas generated by the thermal decomposition of the waste plastic goes out of the cracking feed pipe 21 through the gas outlet 21c and is collected in the reactor 32 and subjected to neutralization. The cracked gas is then sent to the residual chlorine neutralizer 33 where it is further neutralized to remove the chlorine content in the cracked gas and liquefy.

  On the other hand, the pyrolysis residue is conveyed by the feed screw 22 to the residue discharge port 21d at the end of the decomposition feed pipe 21 at the raw material discharge side. Then, it is discharged from the residue discharge port 21 d and stored in the residue tank 30.

  The product oil is refined by the catalyst device 35 and then distilled and separated by the product oil distillation separation device 36 and then stored in the oil storage tank 37 for each type.

  According to the waste plastic oil-reduction apparatus of the present invention having the above-described configuration, the efficiency of oil-reduction reduction can be increased by reducing all of the waste plastics subject to oil-reduction treatment. In addition, the undissolved component does not stagnate or harden in the apparatus, and can be operated stably and the reliability can be improved.

  In addition, although the above-mentioned form is an example of the suitable form of this invention, it is not limited to this, A various deformation | transformation implementation is possible in the range which does not deviate from the summary of this invention. For example, in this embodiment, in order to allow the cracked gas to be naturally discharged from the cracking feed pipe 21, the cracking feed pipe 21 is higher at the raw material discharge side end than the raw material input side end. However, the present invention is not limited thereto, and the decomposition feed pipe 21 is installed horizontally, and an induction fan is provided at the gas outlet 21c to operate the fan. The cracked gas may be sucked.

  In the present embodiment, the charging feed pipe 6 is heated by a heater. However, the present invention is not limited to this, and a hot air passage is formed on the outer periphery of the charging feed pipe as in the case of the decomposition feed pipe 21. You may make it heat with a hot air. Moreover, although the hot air passage is formed in the outer periphery and the melting feed pipe 13 is heated by the hot air, in some cases, a heater may be provided on the outer periphery and heated by the heater.

  Further, as shown in FIG. 2, for example, the present invention is also provided by providing spiral barriers (fins) 42a and 43a in the lower space 42 and the upper space 43 of the decomposition device 41 in the thermal decomposition device 40 of Japanese Patent Laid-Open No. 2000-1677. Is realized.

  In the present embodiment, the extruder 4, the input feed pipe 6, and the melting feed pipe 13 are configured. However, the extruder 4 may be omitted. In this case as well, the waste plastic raw material can be dissolved by the charging feed pipe 6 and the melting feed pipe 13 and the waste plastic raw material can be subjected to oil reduction treatment. In this case, similarly to the decomposition feed pipe 21, a hot air passage is formed on the outer periphery of the input feed pipe 6, and the waste plastic material moving in the input feed pipe 6 is heated by the hot air.

  Alternatively, when the waste plastic raw material can be melted by the extruder 4 with the extruder 4, the length of the feed pipe 6 for making the feed is shorter than that without the extruder 4 or A configuration without the feed pipe 6 or a configuration without the input feed pipe 6 and the dissolution feed pipe 13 is also possible. In this case as well, the oil reduction treatment can be performed on the waste plastic raw material.

  Moreover, in this embodiment, although it is comprised as what has the catalyst apparatus 35, it can also be set as the structure which does not have the catalyst apparatus 35 depending on the case. In this case as well, the oil reduction treatment can be performed on the waste plastic. Further, instead of the catalyst device 35 or between the catalyst device 35 and the product oil distillation separation device 36, a centrifuge device is provided to separate and eliminate moisture and foreign matter in the product oil, and to the product oil. The purification process may be performed.

  Further, in the present embodiment, an example has been described on the assumption that waste plastic is subjected to oil reduction treatment. However, the processing object of the present invention is not limited to this, and may be used as an apparatus for recycling waste oil. It can be used.

  An embodiment in which the waste plastic oil reduction apparatus of the present invention is applied to an actual industrial waste plastic raw material oil reduction process will be described.

  In the present embodiment, the waste plastic oil reduction apparatus 1 has a length of feed pipe 6 of about 1.5 m and a diameter of about 22 cm, a length of melt feed pipe 13 of about 3 m and a diameter of about 22 cm, and a feed pipe for decomposition. 21 having a length of about 7 m and a diameter of about 22 cm was used. In the present embodiment, the rotation speed of the dissolution feed pipe 13 was 3 times / minute, and the rotation speed of the decomposition feed pipe 21 was 1 time / minute.

  And in the present Example, the heating temperature in the extruder 4 was adjusted to about 200 degreeC.

  In this embodiment, the temperature of the hot air passing through the hot air passage 13b is about 480 ° C. at the inlet 18a, that is, the raw material discharge side end, and is about 380 ° C. at the exhaust port 18b, ie, the raw material input side end. Thus, the heating power of the burner 17 in the first hot air generating furnace 16 was controlled.

  Further, the temperature of the hot air passing through the hot air passage 21b is about 550 ° C. at the inlet 26a, that is, the raw material discharge side end portion, and about 450 ° C. at the exhaust port 26b, ie, the raw material input side end portion side. The heating power of the burner 25 in the hot air generator 24 was controlled.

  In this example, the oil reduction treatment was performed using 500 g of a so-called 3P (that is, polystyrene / polypropylene / polyethylene) mixed raw material of industrial waste plastic. In addition, the structure of the mixed raw material used by the present Example was 150g of polystyrene, 150g of polypropylene, and 200g of polyethylene.

  Using the actual machine having the configuration of the present invention, 500 g of the raw material was subjected to oil reduction treatment, and 400 cc of produced oil was extracted. In this example, the oil reduction treatment of 500 g of the raw material was completed in about 50 minutes.

  The resulting 400 cc product oil was separated by a distillation test to obtain the following components.

1) Light oil 40cc (10% of the total)
This is an oil extracted by thermal decomposition in the range of 0-130 ° C.
Gasoline and naphtha fractions that can be recycled into petrochemical products.
2) Kerosene / light oil equivalent 335cc (83.75% of the total)
This is an oil extracted by thermal decomposition in the range of 131-350 ° C.
It is a kerosene / light oil fraction and can be recycled for boiler fuel, diesel oil, etc.
3) A heavy oil equivalent 25cc (6.25% of the total)
This is an oil extracted by thermal decomposition in the range of 351 ° C. or higher.
It is a heavy oil fraction and can be reused for boiler fuel, marine fuel, etc.
It can also be used as a fuel for a burner of a hot air generating furnace of an oil reduction apparatus.

  From the results of the above examples, it was confirmed that the waste plastic oil reduction apparatus of the present invention has a low carbonization rate and an excellent thermal decomposition efficiency, and can achieve a very high product oil recovery rate.

It is a block diagram which shows an example of embodiment of the waste plastic oil-ized reduction apparatus of this invention. It is a block diagram which shows other embodiment of the waste plastic oil reduction apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Waste plastic oil reduction apparatus 3 Raw material input hopper 6 Input feed pipe 13 Dissolution feed pipe 13b Hot air passage 18 Hot air passage cover 21 Decomposition feed pipe 21b Hot air passage 26 Hot air passage cover

Claims (4)

  While sending the waste plastic raw material in the melted state on the screw conveyor in a state separated from the outside air, primary decomposition and secondary decomposition are continuously performed by the heat of the hot gas guided to the hot air passage formed around the screw conveyor. In the oil reduction apparatus, a waste plastic oil reduction apparatus characterized in that a spiral barrier is arranged in the hot air passage, and the hot gas passes spirally along the outer peripheral surface of the screw conveyor. .   A melting feed pipe that has a spiral hot air passage that is separated from the outside air by a cover that covers the outside and melts the waste plastic raw material by heating, and a spiral hot air passage that is separated from the outside air by the cover that covers the outside The temperature gradually increases from the side where the waste plastic material is introduced from the melting feed pipe toward the opposite side by injecting hot air into the hot air passage from the side where the waste plastic material is discharged. A decomposition feed pipe for separating a decomposition gas by heating and thermally decomposing the waste plastic raw material supplied from the melting feed pipe by forming a temperature gradient, a hot air passage of the melting feed pipe, and the decomposition A hot air generating furnace for generating hot air to be supplied to the hot air passage of the feed pipe Waste plastics Yuka reduction device according to claim.   3. The waste plastic oil reduction apparatus according to claim 2, further comprising a nitrogen gas generator for generating nitrogen gas to be injected into the melting feed pipe and the decomposition feed pipe.   4. The decomposition feed pipe is installed such that an end on the opposite side is higher than an end on the side where the waste plastic raw material is charged from the melting feed pipe. The waste plastic oil reduction apparatus as described.

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