JP7584785B2 - Apparatus and method for pyrolysis of organic waste - Google Patents

Description

The present invention relates to a pyrolysis device and a pyrolysis method for pyrolyzing organic waste and recovering pyrolyzed charcoal from the organic waste.

Patent Document 1 describes a conventional pyrolysis device that pyrolyzes organic waste and recovers pyrolyzed carbonized material from the organic waste. The pyrolysis device includes an inner container as a dry distillation tank for pyrolyzing the organic waste contained therein, and an outer container as a heating furnace for heating the inner container, and is heated while being rotated around the axis of the inner container as the center of rotation to perform pyrolysis.

JP 2005-255841 A

However, the thermal decomposition apparatus described in Patent Document 1 has a problem in that the area of the dry distillation tank in contact with the heating furnace is small, so the heat from the heating furnace is not transferred efficiently to the dry distillation tank.

In view of the above, the present invention aims to provide a pyrolysis device that can efficiently transfer heat from a heating furnace to a dry distillation tank.

The pyrolysis apparatus according to the present invention is a pyrolysis apparatus including a dry distillation tank for dry distilling organic waste, an input device for inputting the organic waste into the dry distillation tank, and a heating furnace for heating the dry distillation tank to dry distill the organic waste,
The heating furnace is characterized in that a plurality of the dry distillation tanks are provided in parallel.

According to the pyrolysis device of the present invention, organic waste put into the dry distillation tank is heated by a heating furnace that heats the dry distillation tank, and by heating, the waste is dry distilled (pyrolyzed) and can be recycled into a carbonized material that can be used as fuel, a soil conditioner, a water purification agent, or the like. Since multiple dry distillation tanks are provided in parallel inside the heating furnace, the total surface area of the dry distillation tanks in contact with the heating furnace can be increased. As a result, this pyrolysis device can efficiently transfer heat from the heating furnace to the dry distillation tank.

Here, in the above pyrolysis apparatus, the heating furnace is cylindrical and configured to be rotatable about a central axis of the cylindrical shape,
The plurality of dry distillation tanks may be arranged at equal intervals on an imaginary cylinder centered on the rotation axis.

According to this, multiple dry distillation tanks arranged on a cylinder centered on the rotation axis of the heating furnace revolve around the rotation axis of the heating furnace. Therefore, the heating furnace can uniformly heat the multiple dry distillation tanks arranged in parallel.

In the above pyrolysis apparatus, end walls for closing the heating furnace are provided at both ends of the heating furnace, and a combustion mechanism for generating hot air is provided at the one end of the heating furnace.
The heating furnace penetrates the housing of the combustion mechanism,
The heating furnace may be arranged in the housing and have an open portion in the circumferential direction of the outer cylinder thereof.

This allows the hot air generated by the combustion mechanism to be directed directly at the dry distillation tank inside the heating furnace through the open part of the heating furnace, allowing the dry distillation tank to be heated efficiently.

The pyrolysis device may also be configured to have an exhaust port for the hot air on the rotation axis of the end wall on the other end side, and a hot air passage that serves as a passage for the hot air from the combustion mechanism may be formed within the heating furnace.

This allows hot air to flow from one end to the rear end, so the dry distillation tank can be heated efficiently.

In addition, in the above-mentioned pyrolysis device, a plurality of partition plates that support the dry distillation tank and separate the hot air passage are provided between the end wall on the one end side and the end wall on the other end side, and the partition plates can be configured so that the dry distillation tank passes through the partition plates, and hot air holes through which hot air passes are provided at different installation positions on adjacent partition plates.

With this, the partition boards support the dry distillation tank, and the hot air holes through which the hot air passes are installed at different positions on each partition board, so the flow of hot air in the hot air duct can be changed and the dry distillation tank can be heated evenly by the heating furnace.

In the pyrolysis apparatus, a receiving pipe for receiving the organic waste is connected to the rotary shaft at one end of the heating furnace so as to be rotatable with respect to the input device,
a distribution path for distributing the organic waste to each of the dry distillation tanks is provided in a radial direction within the heating furnace from the other end side of the receiving pipe;
The distribution passage may be connected to one end of each of the dry distillation tanks.

According to this, the receiving pipe is rotatable relative to the input device, and a distribution path is provided for distributing the organic waste from the receiving pipe to each of the dry distillation tanks. Therefore, while rotating the heating furnace equipped with the dry distillation tanks, the organic waste can be distributed to each of the dry distillation tanks.

In addition, in the pyrolysis method using the pyrolysis device, biomass fuel can be used as the fuel for combustion in the heating furnace.

By doing this, since biomass fuel absorbs carbon dioxide during the growth process, it is possible to carry out pyrolysis processing while minimizing environmental destruction.

The pyrolysis device of the present invention can efficiently transfer heat from the heating furnace to the dry distillation tank.

FIG. 1 is a conceptual diagram of a pyrolysis apparatus according to an embodiment of the present invention. FIG. 2 is a conceptual diagram of the dry distillation tank and heating furnace of the pyrolysis apparatus. FIG. 2 is a conceptual diagram of an input device for the pyrolysis apparatus. FIG. 2 is a conceptual diagram of an agglomeration device of the pyrolysis apparatus. 3 is a vertical cross-sectional view of the dry distillation tank and the heating furnace, taken along line V-V in FIG. 2. 6 is a vertical cross-sectional view of the dry distillation tank and the heating furnace, taken along line VI-VI in FIG. 2. 7 is a vertical cross-sectional view of the dry distillation tank and the heating furnace including the stand, taken along line VII-VII in FIG. 2. 8 is a partial horizontal cross-sectional view of one end of the dry distillation tank and the heating furnace, taken along line VIII-VIII in FIG. 2. 9 is a partial horizontal cross-sectional view of the other end side of the dry distillation tank and the heating furnace, taken along line IX-IX in FIG. 2. 3 is a vertical cross-sectional view of the distributor of the pyrolysis apparatus, taken along line XX of FIG. 2.

Hereinafter, an embodiment of the pyrolysis apparatus of the present invention will be described. As shown in Figs. 1 and 2, the pyrolysis apparatus A of the embodiment includes a pyrolysis tank group 2 having six cylindrical pyrolysis tanks 21 arranged in parallel to continuously pyrolyze waste plastic WP as organic waste while moving it, a heating furnace 1 that covers the pyrolysis tank group 2 and heats the pyrolysis tank 21 by combustion, an input device 4 that inputs the waste plastic WP into the pyrolysis tank group 2, a distribution device 3 that distributes the input waste plastic WP to each of the pyrolysis tanks 21, and a recovery device 5 that recovers charcoal CB and pyrolysis gas DG generated by the pyrolysis of the waste plastic WP by heating. As described later, the heating furnace 1 is configured to be rotatable around the central axis (rotation axis RA) of the cylindrical shape, and the six pyrolysis tanks 21 of the pyrolysis tank group 2 are arranged at equal intervals on a virtual cylinder centered on the rotation axis RA. Each dry distillation tank 21 is fixed to the heating furnace 1 so that its central axis is parallel to the rotation axis RA, and is configured to rotate (revolve) together with the heating furnace 1. In this specification, the orientation of the pyrolysis device A is as shown in Figures 1 and 2, with the side having the input device 4 being the front and the side having the recovery device 5 being the rear. Up, down, left, and right refer to the up, down, left, and right of the pyrolysis device A as viewed from the front, and as used in the figures, F refers to the front, B refers to the rear, U refers to the top, D refers to the bottom, L refers to the left, and R refers to the right. The circumferential direction of the rotation of the dry distillation tank 21 refers to the direction (e.g., clockwise) of the pyrolysis device A as viewed from the front.

As shown in FIG. 2, the heating furnace 1 is a furnace that covers the dry distillation tank group 2 consisting of six dry distillation tanks 21 arranged in parallel in the front-to-rear direction, which will be described in detail later, and a combustion mechanism 14 described later burns biomass fuel BF and heats the dry distillation tank group 2 using hot air generated by the combustion. The heating furnace 1 covers the dry distillation tank group 2, has a cylindrical shape with the axial direction being the front-to-rear direction, and is configured to be rotatable in the circumferential direction around the central axis of the cylindrical shape as the rotation axis RA. The front end wall 11a, which is the end wall on one end side of the heating furnace outer tube 11 of the heating furnace 1, is formed with a front side shaft 11c that serves as the axis of rotation of the heating furnace 1 that rotates in the circumferential direction, and the rear end wall 11b, which is the end wall on the other end side of the heating furnace outer tube 11, is formed with a rear side shaft 11d that serves as the axis of rotation of the heating furnace 1 that rotates in the circumferential direction. The front side shaft 11c is hollow, and the inside of the hollow shaft also serves as a receiving pipe 31, which will be described later. The rear shaft 11d is also hollow, and the inside of the hollow shaft also serves as the exhaust passage 15, which will be described later.

A rotating gear 16 is provided endlessly in the circumferential direction on the outer periphery of the furnace outer cylinder 11, approximately at the center in the front-to-rear direction. A drive gear 17 that meshes with the rotating gear 16 and a motor 17a that rotates the drive gear 17 are provided below the rotating gear 16. The furnace outer cylinder 11 (furnace 1) is configured to rotate in the circumferential direction around the central axis of the cylinder (rotation axis RA) by the rotation of the motor 17a. The furnace outer cylinder 11 is rotatably installed at the installation location G on two stands 18 at the front and rear via rotating rollers 18a, as shown in Figures 2 and 7.

At the front end of the heating furnace 1, a combustion mechanism 14 is installed as a heat source to generate combustion heat. The housing 14a of the combustion mechanism 14 covers the entire radial circumference of the front end of the heating furnace 1 (FIG. 10). The combustion device 14b and the fuel supply pump 14c that supplies biomass fuel BF to the combustion device 14b are connected to the lower side of the housing 14a. The fuel supply pump 14c supplies biomass fuel BF to the lower part of the housing 14a, and the biomass fuel BF is combusted by the combustion device 14b connected to the lower part of the housing 14a. The combustion mechanism 14 generates combustion heat by burning the biomass fuel BF with the combustion device 14b. Note that volatile oil VO and oil droplets OD, which will be described later, can also be used as fuel for the combustion mechanism 14.

As shown in Figures 2 and 8, the combustion mechanism 14 is fixed to the installation location G, and a through hole 14d is formed in the housing 14a, which passes the heating furnace 1 from front to back, and the heating furnace 1 passes through the housing 14a. Since the heating furnace 1 rotates circumferentially around the rotation axis RA with respect to the through hole 14d, a gland packing 14e is provided on the outer periphery in front of and behind the through hole 14d. The housing 14a is structured such that the gland packing 14e allows the heating furnace 1 to rotate with respect to the through hole 14d while preventing the outflow of heat from the combustion mechanism 14.

As shown in FIG. 8, an open section 11e is formed at the front side of the heating furnace 1 arranged inside the housing 14a, where the outer shell of the heating furnace outer cylinder 11 is open all around in the circumferential direction. This allows heat from the combustion mechanism 14 (combustion device 14b) to pass through the open section 11e and directly heat the dry distillation tank group 2. The heating furnace 1 on the front side of the open section 11e and the heating furnace 1 on the rear side of the open section 11e are connected by six dry distillation tanks 21, so they can rotate in a circumferential direction around the rotation axis RA in unison.

An exhaust passage 15 is provided inside the rear shaft 11d of the heating furnace 1. The hot air from the combustion mechanism 14 flows through the hot air passage 13 through which the hot air in the heating furnace 1 passes, heats the dry distillation tank group 2, and is then discharged to the outside through the exhaust passage 15. A damper 15a that regulates or adjusts the flow rate of the hot air is provided inside the rear of the exhaust passage 15, and the temperature inside the heating furnace 1 can be adjusted by adjusting the flow rate of the hot air.

Between the front end wall 11a and the rear end wall 11b of the heating furnace 1, five circular partition plates 12 that divide the hot air passage 13 are arranged so as to divide the hot air passage 13 into six in the front-rear direction. The five partition plates 12 are, from the front, the first partition plate 12a, the second partition plate 12b, the third partition plate 12c, the fourth partition plate 12d, and the fifth partition plate 12e. As shown in Figure 5, the first partition plate 12a, the third partition plate 12c, and the fifth partition plate 12e have six hot air holes 13a through which hot air passes on the radially outer side of the partition plate 12. As shown in Figure 6, the second partition plate 12b and the fourth partition plate 12d have hot air holes 13a through which hot air passes in the center of the partition plate 12. As a result, the hot air sent from the combustion mechanism 14 flows backward while moving between the outside and inside of the heating furnace outer cylinder 11 in the radial direction, and flows into the exhaust passage 15 of the rear shaft 11d of the heating furnace 1. The hot air sent from the combustion mechanism 14 flows backward while moving between the outside and inside of the heating furnace outer cylinder 11 in the radial direction in addition to the axial rotation of the heating furnace outer cylinder 11, so that the dry distillation tanks 21 of the dry distillation tank group 2 can be efficiently heated. The partition plate 12 has holes that penetrate each dry distillation tank 21, and the hot air holes 13a are arranged one by one on the outside between the holes that penetrate the adjacent dry distillation tanks. The partition plate 12 also serves as a support for the dry distillation tank group 2.

The group of dry distillation tanks 2 consists of six dry distillation tanks 21, which are arranged in parallel inside the heating furnace 1, and the six dry distillation tanks 21 are arranged at equal intervals on an imaginary cylinder centered on the rotation axis RA of the heating furnace 1 and are fixed to the heating furnace 1. By having six dry distillation tanks 21, the pyrolysis device A of the embodiment has a larger total surface area of the dry distillation tanks 21 and has superior thermal efficiency compared to a pyrolysis device having one dry distillation tank.

The dry distillation tanks 21 are heated in the heating furnace 1, and the waste plastic WP as organic waste is continuously dry distilled while being moved. The six dry distillation tanks 21 in the dry distillation tank group 2 are blocked at the front by the input device 4 and at the rear by the recovery device 5, and are isolated from the outside air, including the hot air from the heating furnace. As a result, oxidation of the dry distillation gas DG and carbonized matter CB generated from the waste plastic WP during dry distillation is suppressed, and deterioration (oxidation) is minimized.

8 and 9, each dry distillation tank 21 has four rows of agitator blades 25 arranged in a row along the axial direction (front-rear direction) of the inner circumferential surface 21a. The rows of agitator blades protrude from the inner circumferential surface 21a of the dry distillation tank 21 so as to divide the inner circumferential surface 21a of the dry distillation tank 21 into four equal parts along the circumferential direction. Therefore, by rotating the dry distillation tank 21, the waste plastic WP can be easily agitated and rolled, and uneven heating of the waste plastic WP can be suppressed. The agitator blades 25 are arranged so that the rear end of each of them is shifted counterclockwise compared to the front end. Therefore, when the dry distillation tank 21 (heating furnace 1) is rotated clockwise, the waste plastic WP as the contained material is agitated and rolled so as to move backward, and when the dry distillation tank 21 is rotated counterclockwise, the waste plastic WP is agitated and rolled so as to move forward. By changing the rotation direction of the dry distillation tank 21, the waste plastic moves back and forth, making it possible to adjust the time for dry distilling the waste plastic WP.

Waste plastic WP, which is organic waste that is dry-distilled in the dry-distillation tank 21, is pumped by the input device 4 to the distribution device 3, from which it is distributed to each of the six dry-distillation tanks 21.

As shown in Figures 2, 8, and 10, the distribution device 3 is composed of a receiving pipe 31 that transfers the waste plastic WP from the input device 4 to the distribution device 3, a distribution section 32 that distributes the transferred waste plastic WP to the six dry distillation tanks 21, and a distribution path 33 that connects the distribution section 32 to each of the six dry distillation tanks 21.

As shown in FIG. 2, the receiving pipe 31 is a pipe that receives waste plastic WP from the input device 4 and transfers it to the distribution section 32, and is a hole that penetrates the hollow front shaft 11c in the axial direction. The receiving pipe 31 is fixed to the heating furnace 1 and rotates in the circumferential direction, so that it is rotatably connected to the input device 4. The receiving pipe 31 is connected to the delivery port 41d of the first screw pump 41 of the input device 4 so as to cover the delivery port 41d, and a gland packing 31a that blocks air (oxygen) from the outside air is provided at the tip of the receiving pipe 31. As shown in FIG. 8, the distribution section 32 is a container arranged on the central rotation axis RA at the front end side of the six dry distillation tanks 21 arranged on a cylinder centered on the rotation axis RA. Six distribution paths 33 that communicate with each of the six dry distillation tanks 21 are connected to the distribution section 32, and the transferred waste plastic WP is distributed to each distribution path 33. The distribution section 32 distributes the waste plastic WP to the six dry distillation tanks 21 by transporting the waste plastic WP downward by its own weight along the distribution path 33 that rotates around the rotation axis RA.

As shown in Figures 8 and 10, an inclined surface 24 is provided on the inner peripheral surface 21a of the dry distillation tank 21, which is on the outer side of the rotation axis RA at the portion where the distribution path 33 on the front end side of the dry distillation tank 21 is connected, to facilitate the transfer of waste plastics WP to the rear. The inclined surface 24 is a surface that inclines in the direction of the rotation axis RA from rear to front on the inner peripheral surface 21a of the dry distillation tank 21, which is on the outer side of the rotation axis RA, and closes the dry distillation tank 21. The inclined surface 24 allows the waste plastics WP to be easily transferred to the rear and prevents the waste plastics WP from accumulating on the front end side of the dry distillation tank 21.

As shown in FIG. 1, an input device 4 that inputs waste plastic WP is connected to the receiving pipe 31 of the distribution device 3. As shown in FIG. 3, the input device 4 includes a first screw pump 41 that inputs waste plastic WP into the dry distillation tank 21, and a second screw pump 42 that supplies waste plastic WP to the first screw pump 41.

The first screw pump 41 is equipped with a screw 41b that rotates to pump waste plastic WP inside a pump outer cylinder 41c that serves as a housing, and a motor 41a that rotates the screw 41b at the front of the pump outer cylinder 41c. The pump outer cylinder 41c has a supply port 41e at the front upper part to which waste plastic WP is supplied from the second screw pump 42, and the waste plastic WP supplied from the supply port 41e is pumped rearward by the rotation of the screw 41b and transferred from the delivery port 41d at the rear end of the pump outer cylinder 41c to the receiving pipe 31 of the distribution device 3.

A nitrogen inlet 19 for supplying nitrogen to the dry distillation tank 21 is provided near the delivery outlet 41d at the rear end of the pump outer cylinder 41c. This makes it possible to prevent air (oxygen) from entering from the outside by supplying nitrogen when the pressure inside the dry distillation tank 21 is reduced. Nitrogen is supplied by a nitrogen cylinder 19a connected to the nitrogen inlet 19.

In the first screw pump 41, the waste plastic WP is pumped backward by the rotation of the screw 41b, degassed by the pressure of the rotation of the screw 41b, transported backward inside the pump outer cylinder 41c so that the air (oxygen) is removed, and then fed into the dry distillation tank 21. The pump outer cylinder 41c is provided with an oil inlet 41f for injecting oil. In the first screw pump 41, oil (oil droplets OD) is injected from the oil inlet 41f to fill the spaces between the waste plastic WP particles with oil, further promoting degassing, and transferring the waste plastic WP to the dry distillation tank group 2.

The second screw pump 42 is a pump that supplies waste plastic WP to the first screw pump 41, and has the same basic configuration as the first screw pump 41. The second screw pump 42 is provided with a screw 42b that pressurizes the waste plastic WP by rotating inside a pump outer cylinder 42c that serves as a housing, and a motor 42a that rotates the screw 42b in front of the pump outer cylinder 42c. The second screw pump 42 is provided with a hopper container 43 that stores waste plastic WP in the front upper part of the pump outer cylinder 42c, and a supply port 42e through which waste plastic WP is supplied from the hopper container 43 at the connection between the hopper container 43 and the pump outer cylinder 42c. The waste plastic WP supplied from the supply port 42e is pressurized backward by the rotation of the screw 42b and transferred to the first screw pump 41 from the delivery port 42d at the lower rear end of the pump outer cylinder 42c.

As shown in Figures 1 and 3, the pump outer cylinder 42c of the second screw pump 42 is positioned rearward at an angle α of 5° upward from the horizontal. As the weight of the waste plastic WP is applied to the supply source side, the waste plastic WP is degassed by the pressure of its own weight, and is transported rearward inside the pump outer cylinder 42c so that the air (oxygen) is removed.

As shown in FIG. 3, the screws 41b, 42b of the first screw pump 41 and the second screw pump 42 are formed so that the pitch P per rotation becomes shorter toward the rear. Therefore, the waste plastic WP is compressed toward the rear and transported toward the rear inside the pump outer cylinders 41c, 42c so that the air (oxygen) is removed.

The supply port 41e of the first screw pump 41 and the delivery port 42d of the second screw pump 42 are connected by a connecting pipe 44 arranged in the vertical direction. A first gate valve 44a that closes the inside of the connecting pipe 44 is provided on the lower side of the connecting pipe 44 (the supply port 41e side of the first screw pump 41), and a second gate valve 44b that closes the inside of the connecting pipe 44 is provided on the upper side of the connecting pipe 44 (the delivery port 42d side of the second screw pump 42). By opening and closing the first gate valve 44a or the second gate valve 44b, the waste plastic WP can be transported smoothly.

As shown in FIG. 2, the recovery device 5 is a device that recovers charcoal CB and pyrolysis gas DG generated by thermal decomposition of waste plastic WP. The recovery device 5 has a receiving port 56 at the front side for receiving charcoal CB and pyrolysis gas DG, and the receiving port 56 is connected to cover the rear end of the heating furnace outer cylinder 11. The receiving port 56 rotatably supports the rear end of the heating furnace outer cylinder 11, and a gland packing 56a is provided on the outer periphery of the receiving port 56, which is structured to prevent the inflow of air (oxygen). Granular charcoal CB and gaseous pyrolysis gas DG generated in the pyrolysis tank group 2 in the heating furnace outer cylinder 11 are transported to the recovery device 5, and the charcoal CB with a high specific gravity accumulates in the solid reservoir 52 at the bottom of the recovery device 5, and the pyrolysis gas DG with a low specific gravity accumulates in the gas reservoir 51 at the top of the recovery device 5. A rotary valve 54 is provided below the solid reservoir 52 to block outside air and discharge granular solids to the bottom, and the carbide CB is discharged to the bottom and collected. A check valve 53 is provided above the gas reservoir 51 to prevent the inflow of outside air and discharge gas, and the dry distillation gas DG is transferred to the gas separation device 6 described next. In addition, a hat-shaped baffle 51a is provided above the gas reservoir 51 to prevent the outflow of dust contained in the dry distillation gas DG.

As shown in FIG. 4, the gas separation device 6 is a device that separates and recovers the dry distillation gas DG in the recovery device 5 into volatile oil VO, oil droplets OD, and water droplets WD. The gas separation device 6 is equipped with an ejector 70 that sucks in the dry distillation gas DG, a gas-liquid separation tank 61 that separates the volatile oil VO and liquid droplets LD from the dry distillation gas DG, and an oil recovery device 62 and a moisture recovery device 63 that respectively separate and recover the oil droplets OD and water droplets WD separated from the liquid droplets LD.

The ejector 70 is a device that sucks in the dry distillation gas DG by using the ejector effect. It circulates the liquid droplets LD in the gas-liquid separation tank 61 through the circulation path 70c at high speed using the liquid pump 70b, and ejects the liquid droplets LD at high speed from the nozzle 70a in the ejector 70 to create a low pressure near the nozzle 70a, thereby sucking in the dry distillation gas DG. The ejector 70 uses its suction capacity to suck in the volatile oil VO in the recovery device 5 and transfers the volatile oil VO to the gas-liquid separation tank 61.

The gas-liquid separation tank 61 is a closed vessel, and has a gas outlet 61a at the top for recovering volatile oil VO, and a liquid droplet reservoir 61b at the bottom where liquid droplets LD accumulate. In the gas-liquid separation tank 61, the dry distillation gas DG transferred by the ejector 70 is discharged into the liquid droplets LD in the liquid droplet reservoir 61b. The dry distillation gas DG discharged into the liquid droplets LD is cooled by the liquid droplets LD, and the liquefied dry distillation gas DG becomes liquid droplets LD and accumulates in the liquid droplet reservoir 61b, while the dry distillation gas DG that is not liquefied even after cooling becomes volatile oil VO and accumulates at the top. By discharging the dry distillation gas DG into the liquid droplets LD, harmful substances such as hydrogen sulfide and hydrogen chloride contained in the dry distillation gas DG can be dissolved in the liquid droplets LD, and the release of harmful substances can be prevented. The volatile oil VO that accumulates on the upper side is filled into the water-containing gas holder 68 and used as fuel for the combustion device 14b of the heating furnace 1, the generator 69, etc.

The droplets LD that accumulate in the droplet reservoir 61b are a mixture of oil droplets OD and water droplets WD. Because the oil droplets OD and water droplets WD are not compatible, the droplets LD are separated into oil droplets OD and water droplets WD due to the difference in specific gravity. The oil droplets OD that float on the upper side of the gas-liquid separation tank 61 are collected from an oil collector 62 that is a funnel-shaped container with an open top. The water droplets WD that accumulate at the bottom of the droplet reservoir 61b are collected from a moisture collector 63 that is placed in the water droplets WD. The oil droplets OD collected from the oil collector 62 are further dewatered in an oil-water separation tank 64 that separates water and oil, and are stored in an oil collection tank 66. The water droplets WD that are collected from the moisture collector 63 are further dewatered in an oil-water separation tank 65, and are stored in a moisture collection tank 67 and discharged as sewage.

Sediments S, such as dust and tar, which have a higher specific gravity (1.1 to 1.2) than water droplets WD, settle at the bottom of the gas-liquid separation tank 61. For this reason, a drain 61c for discharging the sediments S is provided at the bottom of the gas-liquid separation tank 61.

The gas-liquid separation tank 61 is equipped with a neutralizing agent injector 61e that injects a neutralizing agent (aqueous sodium hydroxide solution) that neutralizes the liquid droplets LD. When harmful substances such as hydrogen sulfide and hydrogen chloride contained in the dry distillation gas DG dissolve in the liquid droplets LD and the pH of the liquid droplets LD changes to the acidic side, the neutralizing agent injector 61e neutralizes the liquid droplets LD to prevent corrosion of the gas-liquid separation tank 61.

The gas-liquid separation tank 61 is equipped with a cooling tower 61d that circulates the liquid droplets LD to cool them. The liquid droplets LD are constantly heated because the high-temperature dry distillation gas DG dry distilled by heat is released into the liquid droplets LD. For this reason, a cooling tower 61d is provided to cool the liquid droplets LD, and the liquid droplets LD are cooled. The cooling tower 61d is equipped with a heat exchanger (not shown), and is reused as a heat source for the heating equipment and road heating in the facility equipped with the pyrolysis device A.

Next, the operation of the pyrolysis device A of the embodiment will be described. In the pyrolysis device A of the embodiment, waste plastic WP is used as the organic waste to be dry distilled, and biomass fuel BF is used as the fuel for the combustion device 14b of the heating furnace 1.

Waste plastic WP as organic waste is fed into the distribution device 3 of the pyrolysis device A by the feeding device 4, which is composed of a second screw pump 42 and a first screw pump 41 arranged in series. The feeding is performed by alternately operating the second screw pump 42 and the first screw pump 41, and alternately opening and closing the second gate valve 44b and the first gate valve 44a at the top and bottom of the connecting pipe 44, thereby blocking air and feeding the waste plastic WP into the distribution device 3 of the pyrolysis device A. In addition, since the pitch P of one rotation of the screws 41b and 42b of the first screw pump 41 and the second screw pump 42 is formed so as to become shorter toward the rear, the waste plastic WP is compressed toward the rear and transported backward inside the pump outer cylinders 41c and 42c so that the air (oxygen) is removed. By being pumped by the second screw pump 42 and the first screw pump 41, the waste plastic WP is transported through the pump outer cylinders 41c, 42c while being degassed by the pressure of the rotation of the screws 41b, 42b. By injecting oil (oil droplets OD) from the oil inlet 41f of the first screw pump 41, the oil fills the spaces between the waste plastic WP particles, further promoting degassing. The waste plastic WP is degassed and fed into the distribution device 3 of the pyrolysis device A.

Waste plastic WP fed into the distribution device 3 of the pyrolysis device A falls downward from the distribution section 32 of the distribution device 3 and is distributed to each of the distribution paths 33 connected to the front ends of the six dry distillation tanks 21 that rotate around the rotation axis RA. The waste plastic WP travels backward along the inclined surface 24 that facilitates movement backward from the distribution path 33, and is fed into each dry distillation tank 21.

In the heating furnace 1, the biomass fuel BF is combusted in the housing 14a by the combustion device 14b of the combustion mechanism 14, and the dry distillation tank 21 of the dry distillation tank group 2 that penetrates the housing 14a is directly heated through the open portion 11e. The waste plastic WP fed into the dry distillation tank 21 is heated and dry distilled by the combustion of the biomass fuel BF in the combustion device 14b of the heating furnace 1 that is separated from the dry distillation tank 21 while being agitated by the rotation of the dry distillation tank 21 that rotates together with the heating furnace 1 and the agitator blades 25 on the inner surface 21a of the dry distillation tank 21.

In the heating furnace 1 (hot air passage 13), the hot air flows backward while moving between the inside and outside of the heating furnace outer cylinder 11 due to the difference in the installation position of the hot air hole 13a provided in the partition plate 12, and the dry distillation tank 21 revolves around the rotation axis RA, so that the dry distillation tank 21 is heated evenly. The hot air that heated the dry distillation tank 21 flows into the exhaust passage 15 in the rear shaft 11d of the heating furnace 1. Inside the exhaust passage 15, a damper 15a that regulates or adjusts the flow rate of the hot air is provided, and the temperature inside the heating furnace 1 is adjusted by adjusting the flow rate of the hot air. The temperature inside the heating furnace 1 is adjusted to be about 10°C above 800°C. This is to prevent the generation of dioxins. In this case, the temperature inside the dry distillation tank 21 is about 300°C.

Each dry distillation tank 21 in the dry distillation tank group 2 is equipped with an agitator blade 25 on the cylindrical inner peripheral surface 21a, and the dry distillation tank 21 itself revolves in the circumferential direction around the rotation axis RA. As a result, the waste plastic WP is heated while being agitated, uneven heating is suppressed, it is heated evenly, and the thermal efficiency of heating is excellent. The waste plastic WP is put into the dry distillation tank 21 in a degassed state and heated in that state, so oxidation is suppressed and thermal decomposition proceeds. The waste plastic WP is dry distilled for about 90 minutes. Dry distillation gas DG and carbonized matter CB are generated from the dry distilled waste plastic WP by thermal decomposition. Dry distillation gas DG and carbonized matter CB generated from the waste plastic WP are less deteriorated (oxidized) because oxidation is suppressed.

The carbonized material CB generated from the distilled waste plastic WP rolls inside the distillation tank 21, falls from the outlet 23 into the recovery device 5, and accumulates in the solid reservoir 52. The carbonized material CB is discharged and recovered by a rotary valve 54 installed below the solid reservoir 52. The recovered carbonized material CB contains a lot of charcoal (carbon) and can be reused as fuel, a soil conditioner, a water purification agent, etc.

The dry distillation gas DG generated from the dry distilled waste plastic WP is introduced into the liquid droplet reservoir 61b of the gas-liquid separation tank 61 through the recovery device 5 by suction of the ejector 70 of the gas separation device 6. The dry distillation gas DG introduced into the liquid droplet reservoir 61b is cooled by contacting with the liquid droplets LD, and is separated into condensed liquid droplets LD and volatile oil VO that does not condense even when cooled. The volatile oil VO accumulates on the upper side of the gas-liquid separation tank 61, is filled into the water-containing gas holder 68 from the gas outlet 61a, and is used as fuel for the combustion device 14b of the heating furnace 1, fuel for the generator 69, etc. The liquid droplets LD are discharged into the gas-liquid separation tank 61 and separated into oil droplets OD and water droplets WD. The oil droplets OD are collected in the oil recovery device 62 and can be used as fuel, etc. as recycled oil, and can also be used as oil to be injected from the oil inlet 41f of the first screw pump 41. The water droplets WD are collected in a moisture collector 63, and once it has been confirmed that they do not contain any harmful substances, they can be discharged as sewage.

Example 1
In Example 1, continuous pyrolysis was carried out using the pyrolysis apparatus A of the first embodiment under the following conditions.

Heating furnace 1 φ1100mm (outer diameter 1100mm) x L1500mm
Biomass fuel BF Construction waste wood crushed material 80 kg/h Temperature inside the heating furnace adjusted to 810°C Dry distillation tank 21 φ300 mm x L1550 mm x 6 units Rotation speed 1 rpm Organic waste passing time approx. 90 minutes Dry distillation tank temperature approx. 300°C
First screw pump 41 and second screw pump 42: Transfer rate: 20 kg/h
Gas separation device 6 1200A (inner diameter 1200mm) mm x H2000mm
Ejector 70 65A (air inlet) x 50A (suction port) x 50A (outlet)
Circulation path 70c flow rate 1.1 m ³ /min
Organic waste: crushed used polyethylene containers 10kg/h
In Example 1, kerosene and diesel class oil was obtained as oil droplets OD (recycled oil) at 4 kg/h during steady operation. No water droplets WD were observed. The charcoal CB consisted mainly of charcoal with a maximum diameter of 10 mm. The component particles were obtained at a rate of 1 kg/h.

Example 2
In Example 2, the same pyrolysis apparatus A as in Example 1 was used to continuously carry out pyrolysis under the following conditions.

Biomass fuel BF Construction waste wood crushed material 80 kg/h Temperature inside the heating furnace adjusted to 810°C Dry distillation tank 21 φ300 mm x L1550 mm x 6 units Rotation speed 1 rpm Organic waste passing time approx. 90 minutes Dry distillation tank temperature approx. 300°C
First screw pump 41 and second screw pump 42: Transfer rate: 20 kg/h
Ejector 70 65A (air inlet) x 50A (suction port) x 50A (outlet)
Circulation path 70c flow rate 1.1 m ³ /min
Organic waste Automobile shredder dust 10kg/h
In Example 2, under steady-state operation, 1.5 kg/h of particles mainly composed of charcoal and having a maximum size of about 10 mm were obtained as charcoal CB.

Example 3
In Example 3, the same pyrolysis apparatus A as in Example 1 was used to continuously carry out pyrolysis under the following conditions.

Biomass fuel BF Wood processing waste 80 kg/h Temperature inside the heating furnace adjusted to 810°C Dry distillation tank 21 φ300 mm x L1550 mm x 6 units Rotation speed 1 rpm Organic waste passing time approx. 90 minutes Dry distillation tank temperature approx. 300°C
First screw pump 41 and second screw pump 42: Transfer rate: 20 kg/h
Ejector 70 65A (air inlet) x 50A (suction port) x 50A (outlet)
Circulation path 70c flow rate 1.1 m ³ /min
Organic waste Wood processing waste 10kg/h
In Example 3, no oil droplets OD were observed during steady operation. 4 kg/h of wood vinegar was obtained as water droplets WD. 0.5 kg/h of particles mainly composed of charcoal with a maximum size of about 1 mm was obtained as charcoal CB.

(Other embodiments)
The pyrolysis device of the embodiment can be implemented in the following forms.

In the embodiment of the pyrolysis apparatus, the number of pyrolysis tanks 21 in the pyrolysis tank group 2 is six, but if the number of pyrolysis tanks 21 in the pyrolysis tank group 2 is three to eight, the heat from the heating furnace 1 can be efficiently transferred to the pyrolysis tanks 21. If the number of pyrolysis tanks 21 in the pyrolysis tank group 2 is less than three, the total surface area of the pyrolysis tanks 21 is small, and there is a risk that the heat from the heating furnace 1 cannot be efficiently transferred to the pyrolysis tanks 21. On the other hand, if the number of pyrolysis tanks 21 exceeds eight, each of the pyrolysis tanks 21 becomes small, and there is a risk that the pyrolysis apparatus will be difficult to maintain. More preferably, the number of pyrolysis tanks 21 in the pyrolysis tank group 2 is four to six.

In the embodiment of the pyrolysis device, the open section 11e on the front side of the heating furnace 1 is configured to be open around the entire circumference of the heating furnace outer casing 11, which is the outer shell. However, even if the open section 11e is configured to be open only in part of the circumference of the heating furnace outer casing 11, the heat from the combustion mechanism 14 can pass through the open section 11e and directly heat the dry distillation tank group 2.

In the pyrolysis device of the embodiment, crushed construction waste wood and wood processing waste are used as the biomass fuel BF, but edible oil waste, grain oil, etc. can also be used as the biomass fuel BF. In addition, the fuel used to heat the dry distillation tank 21 is not limited to biomass fuel BF, and general-purpose fuels (city gas, propane gas, etc.) can also be used.

In the pyrolysis device of the embodiment, crushed used polyethylene containers, automobile shredder dust, and wood processing waste were used as organic waste, but there are no particular limitations on the organic waste that can be used, and food waste, feces, and other materials can also be used.

(Other technical ideas)
Other technical ideas that can be understood from the embodiments will be described below.

In the pyrolysis device according to the embodiment, the inner peripheral surface of the dry distillation tank, which is on the outer side of the rotation axis at the end of one end of the dry distillation tank, can be provided with an inclined surface that inclines in the direction of the rotation axis from the other end side to the one end side and closes the dry distillation tank.

This allows organic waste brought in through the connection to be easily moved from one end to the other.

In the pyrolysis apparatus according to the embodiment, the dry distillation tank has a cylindrical shape, and an agitation blade row consisting of a plurality of agitation blades arranged in a row along the axial direction of the dry distillation tank is provided on the inner peripheral surface of the dry distillation tank,
Each of the stirring blades may be configured to be inclined with respect to the axial direction.

According to this, a row of stirring blades is provided on the inner circumferential surface of a cylindrical dry distillation tank, and each stirring blade is provided at an angle to the axial direction. Therefore, by rotating the heating furnace around the central axis of the cylindrical shape and rotating the dry distillation tank provided in the heating furnace, the organic waste in the dry distillation tank can be stirred and moved forward or backward.

1...heating furnace, 2...group of dry distillation tanks, 3...distribution device, 4...feeding device, 5...recovery device, 6...gas separation device, 11...heating furnace outer cylinder, 11a...front end wall, 11b...rear end wall, 11c...front shaft, 11d...rear shaft, 11e...opening, 12...partition plate, 12a...first partition plate, 12b...second partition plate, 12c...third partition plate, 12d...fourth partition plate, 12e...fifth partition plate, 13...hot air duct, 13a...hot air hole, 14...combustion mechanism, 14a...housing, 14b...combustion device, 14c...fuel supply pump, 14d...through Through hole, 14e...gland packing, 15...exhaust passage, 15a...damper, 16...rotating gear, 17...driving gear, 17a...motor, 18...frame, 18a...rotating roller, 19...nitrogen inlet, 19a...nitrogen cylinder, 21...dry distillation tank, 21a...inner circumferential surface, 23...outlet, 24...inclined surface, 25...agitating blade, 31...receiving pipe, 31a...gland packing, 32...distribution section, 33...distribution passage, 41...first screw pump, 41a...motor, 41b...screw, 41c...pump outer cylinder, 41d...delivery port, 41e...supply port, 41f...oil inlet, 42...second screw pump, 42a...motor, 42b...screw, 42c...pump outer cylinder, 42d...delivery outlet, 42e...supply port, 43...hopper container, 44...connecting pipe, 44a...first gate valve, 44b...second gate valve, 51...gas reservoir, 51a...baffle, 52...solid reservoir, 53...check valve, 54...rotary valve, 56...receiving port, 56a...gland packing, 61...gas-liquid separation tank, 61a...gas outlet, 61b...liquid droplet reservoir, 61c...drain, 61d...cooling tower, 61e...neutralization Agent injector, 62...oil recovery device, 63...moisture recovery device, 64...oil-water separation tank, 65...oil-water separation tank, 66...oil recovery tank, 67...moisture recovery tank, 68...water-containing gas holder, 69...generator, 70...ejector, 70a...nozzle, 70b...liquid pump, 70c...circulation path, A...thermal cracking device, BF...biomass fuel, CB...carbonized material, DG...drying gas, G...installation location, LD...liquid droplets, OD...oil droplets, P...pitch, RA...rotating shaft, S...sediment, VO...volatile oil, WD...water droplets, WP...waste plastic, α...angle.

Claims (3)

A pyrolysis apparatus comprising: a dry distillation tank for dry distilling organic waste; an input device for inputting the organic waste into the dry distillation tank; and a heating furnace for heating the dry distillation tank to dry distill the organic waste,
The heating furnace has a cylindrical shape and is configured to be rotatable about a central axis of the cylindrical shape as a rotation axis,
In the heating furnace, a plurality of the dry distillation tanks are arranged at equal intervals on an imaginary cylinder centered on the rotation shaft,
The heating furnace is provided with end walls at each of one end and the other end thereof for closing the heating furnace, a combustion mechanism for generating hot air is provided at the one end thereof, and an exhaust port for the hot air is provided on the rotation shaft of the end wall at the other end thereof, and a hot air passage for the hot air from the combustion mechanism is formed within the heating furnace,
A plurality of partition plates are provided between the end wall on the one end side and the end wall on the other end side to support the dry distillation tank and to separate the hot air passage, the partition plates are penetrated by the dry distillation tank and are provided with hot air holes through which hot air passes,
In the adjacent partition plates, the partition plate having the hot air hole at the center and the partition plate having the hot air hole at the radially outer portion are alternately provided.
An organic waste pyrolysis apparatus comprising: A receiving pipe for receiving the organic waste is rotatably connected to the input device on the rotation shaft at one end side of the heating furnace,
a distribution path for distributing the organic waste to each of the dry distillation tanks is provided in a radial direction within the heating furnace from the other end side of the receiving pipe;
2. The thermal decomposition apparatus for organic waste according to claim 1 , wherein the distribution line is connected to one end of each of the dry distillation tanks. 3. A method for pyrolyzing organic waste, comprising using biomass fuel as a fuel for combustion in the heating furnace of the pyrolysis apparatus for organic waste according to claim 1 or 2 .

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