US20050075521A1 - Method and plant for converting plastic into oil - Google Patents
Method and plant for converting plastic into oil Download PDFInfo
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- US20050075521A1 US20050075521A1 US10/502,624 US50262404A US2005075521A1 US 20050075521 A1 US20050075521 A1 US 20050075521A1 US 50262404 A US50262404 A US 50262404A US 2005075521 A1 US2005075521 A1 US 2005075521A1
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- column
- plastic
- oil
- decomposition
- dissolution
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B53/00—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form
- C10B53/07—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form of solid raw materials consisting of synthetic polymeric materials, e.g. tyres
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G1/00—Production of liquid hydrocarbon mixtures from oil-shale, oil-sand, or non-melting solid carbonaceous or similar materials, e.g. wood, coal
- C10G1/10—Production of liquid hydrocarbon mixtures from oil-shale, oil-sand, or non-melting solid carbonaceous or similar materials, e.g. wood, coal from rubber or rubber waste
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
- C10B47/00—Destructive distillation of solid carbonaceous materials with indirect heating, e.g. by external combustion
- C10B47/28—Other processes
- C10B47/32—Other processes in ovens with mechanical conveying means
- C10B47/44—Other processes in ovens with mechanical conveying means with conveyor-screws
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/141—Feedstock
- Y02P20/143—Feedstock the feedstock being recycled material, e.g. plastics
Definitions
- the present invention relates to a method and a plant for converting plastic into oil for collecting the oil from the plastic.
- the present invention has been mainly made in light of these problems and a primary object of the present invention is to provide a method and a plant for conversion into oil, which are able to convert a large amount of plastic into oil, to treat a hydrogen chloride gas, and to completely treat an off gas.
- the method for conversion into oil comprises heating and dissolving the plastic into expanded plastic, and removing the expanded plastic, heating and depolymerizing it, and cooling it into oil.
- the expanded plastic may preferably be removed by being lifted at an angle, preferably at an angle of 25-30° relative to the horizontal.
- the expanded plastic may preferably be heated with being lifted at an angle and the expanded plastic may preferably be heated to higher temperatures at higher positions.
- the dissolved plastic may preferably be added with vegetable oil or animal oil or mineral oil and heated to generate expanded plastic of their mixture.
- the method for conversion into oil according to the present invention may preferably comprising separating a hydrogen chloride gas generated in dissolving the plastic from other decomposed gases, then reacting the hydrogen chloride gas with hydrated lime, and collecting it as calcium chloride.
- An off gas not converted into oil may preferably be treated by catalytically cracking the off gas with a hot ceramic.
- a plant for conversion into oil comprises a dissolution section for heating and dissolving the plastic into expanded plastic, and a decomposition section for removing the expanded plastic, heating and depolymerizing it, and cooling it into oil.
- the decomposition section may preferably comprise a removal means for removing the expanded plastic by lifting it at an angle, preferably at an angle of 25-30° relative to the horizontal.
- the decomposition section may preferably comprise a heating means for heating the expanded plastic with lifting it at an angle and for heating the expanded plastic to higher temperatures at higher positions.
- the plant may preferably comprise an oil injection means for injecting vegetable oil or animal oil or mineral oil into a connection between the dissolution section and the decomposition section.
- the dissolution section may preferably comprise a plurality of dissolution columns with different temperature ranges.
- the decomposition section may preferably comprise a plurality of tilted decomposition columns with different temperature ranges.
- the plant for conversion into oil may preferably comprise a dechlorination system for treating a hydrogen chloride gas generated in the dissolution section.
- This dechlorination system may preferably comprise a separator for separating the hydrogen chloride gas from other decomposed gases, and a reactor for reacting the hydrogen chloride gas separated by the separator with hydrated lime into calcium chloride.
- the plant may preferably comprise an off gas treatment system for treating an off gas not converted into oil after cooling in the decomposition section by catalytically cracking the off gas with a hot ceramic.
- the plant for conversion into oil according to the present invention may preferably comprise a residual collection means at the top of the final stage decomposition column of the multistage decomposition columns.
- the residual collection means may preferably comprise a column with its upper opening at the top of the final stage decomposition column and its lower opening in an atmosphere of an inactive gas heavier than the air.
- the plant for conversion into oil may preferably comprise a hopper for storing and supplying the plastic into the dissolution section, and the hopper may preferably comprise a lead screw with a spiral blade.
- the plant may preferably comprise an unheated section formed as an unheated area of a predetermined length between the hopper and the dissolution section.
- the plurality of dissolution columns each may preferably comprise a lead screw with a spiral blade for carrying the plastic, and a beginning dissolution column of the plurality of dissolution columns may preferably comprise the lead screw blade with a greater pitch than the lead screws blades in other dissolution columns.
- the dissolution section and the decomposition section each may preferably comprise: an inner column; an outer column around the inner column; a hot air space between the inner column and the outer column and through which an hot air circulates; and a temperature sensor for detecting a temperature in the dissolution section or the decomposition section, and the plant may preferably further comprise a carbon dioxide gas supplying system for supplying the carbon dioxide gas into the hot air space if the temperature sensor detects an abnormal temperature equal to or greater than a predetermined temperature.
- the dissolution section and the decomposition section each may preferably comprise: an inner column; an outer column around the inner column; and a hot air space between the inner column and the outer column and through which an hot air circulates
- the plant may preferably further comprise: a hot air production system for generating by combustion the hot air to be supplied into the hot air space; and a drying system for drying the plastic to be supplied into the dissolution furnace, and an air in the drying system may preferably be supplied into the hot air production system to be deodorized by combustion.
- the air in the drying system may preferably be supplied into the off gas treatment system to be deodorized by being catalytically cracked with a hot ceramic.
- an extendable column which is extendably formed may preferably be used in a part of the dissolution column includes, and the extendable column may preferably comprise: an inner column; a bellows around the inner column which has one end fixed on the inner column and an other end slidable relative to the inner column; and an outer column which is fixed on the other end of the bellows and slidably contains the inner column.
- the dissolution section may preferably comprise: an inner column; an outer column around the inner column; and a heating medium space between the inner column and the outer column and through which a liquid heating medium circulates, and the plant further may preferably comprise a heating medium supplying system for supplying the liquid heating medium into the heating medium space.
- FIG. 1 shows a schematic diagram of the basic principle of the present invention.
- FIG. 2 shows a schematic diagram of an embodiment according to the basic principle of the present invention.
- FIG. 3 shows a schematic perspective view of a plant of conversion into oil of an embodiment according to the present invention.
- FIG. 4 shows a schematic front view of a plant of conversion into oil of an embodiment according to the present invention.
- FIG. 5 shows a schematic plan view of a plant of conversion into oil of an embodiment according to the present invention.
- FIG. 6 shows a schematic diagram of FIG. 5 .
- FIG. 7 shows a schematic diagram of FIG. 4 .
- FIG. 8 shows a schematic transverse cross sectional view of a dissolution column.
- FIG. 9 shows a schematic transverse cross sectional view of a decomposition column.
- FIG. 10 shows a schematic diagram of a dechlorination treatment section.
- FIG. 11 shows a schematic diagram of an off gas treatment section.
- FIG. 12 shows a schematic diagram of another embodiment.
- FIG. 13 shows a schematic diagram of a connection between a dissolution section and a decomposition section.
- FIG. 14 shows recovery rates for different plastics to be treated.
- FIG. 15 shows a schematic illustration of how to lift expanded plastic.
- FIG. 16 shows a schematic transverse cross-sectional view of a hopper.
- FIG. 17 shows a schematic perspective view of an unheated section.
- FIG. 18 shows a schematic diagram of a sludge tank.
- FIG. 19 shows a schematic diagram of an extendable column.
- FIG. 20 shows a schematic diagram of an accident avoidance system and a deodorant system.
- FIG. 21 shows a schematic diagram of another embodiment.
- FIG. 1 shows a conceptual diagram illustrative of the basic principle of a method for converting plastic into oil according to the present invention.
- Plastic raw-material is dissolved at a temperature of 200-350° C. and is stored in a storage section 1 .
- a decomposition column 13 lifts the plastic that is dissolved (dissolved plastic) at an angle.
- the decomposition column 13 includes an inner column 2 , an outer column 6 which forms a hot air space 4 around the inner column 2 , and a lead screw 7 .
- the lead screw 7 includes a rotating shaft 14 and a spiral blade 8 .
- a motor 12 rotates the lead screw 7 at a speed of 4-5 revolutions per minute.
- a pipe 10 supplies a hot air into the hot air space 4 to hold the temperature of the inner column 2 at 350-620° C. for gasification and depolymerization of plastic.
- the lead screw 7 carries through the inner column 2 the dissolved plastic which is primarily decomposed (into the first heavy gas state that is gasified from the dissolved state) in the lower part of the decomposition column 13 to provide a primarily decomposed gas.
- the lead screw 7 carries the primarily decomposed gas at a low speed to the upper part of the decomposition column 13 .
- the primarily decomposed gas is then secondarily decomposed (into a state that is depolymerized from the plastic and can be cooled into oil) in the inner column 2 which is held at 350-620° C. by the hot air supplied from a pipe 15 , to provide a light secondarily decomposed gas.
- One decomposition column is enough to sufficiently secondarily decompose at the upper part of the decomposition column all oil components included in the plastic raw material.
- Two decomposition columns may be used of which the first stage decomposition column connects to the storage section 1 and the second stage decomposition column connects to the first stage decomposition column.
- An outer case 5 resides outside the storage section 1 to form a hot air space 3 into which a hot air is sent.
- the plastic supplied into the storage section is heated to 200-350° C. to provide dissolved plastic mp with foamed plastic (expanded plastic) f formed on its surface.
- This expanded plastic f is heated with being lifted at an angle by a lead screw 7 which has its tip 14 a immersed in the dissolved plastic mp. This can provide a larger contact area between the expanded plastic f and the heat to ensure the decomposition (depolymerization) of the expanded plastic f into the secondarily decomposed gas.
- a pipe 9 collects the secondarily decomposed gas, which is then cooled into oil and stored in an oil storage tank.
- the expanded plastic f is preferably lifted at a speed of 30-60 cm/min. A lower speed will give less carrying efficiency and a higher speed will give insufficient decomposition.
- the lead screw 7 lifts spirally the expanded plastic f as shown in FIG. 15 , preferably by moving it spirally at a speed of 30-60 cm/min. This speed can be adjusted by, for example, the pitch p of the lead screw 7 .
- the expanded plastic f is thus carried at the above-described speed and heated slowly through the inner column 2 to be sufficiently decomposed (depolymerized) in the primary and secondary decomposition temperature areas.
- the expanded plastic f is preferably heated for about 14-15 minutes before it is completely secondarily decomposed at about 600° C.
- the storage section 1 is preferably held at temperatures (200-350° C.) at which the dissolved plastic mp can be expanded.
- temperatures 200-350° C.
- the decomposition column 13 is preferably tilted relative to the horizontal. A hot air circulates through the tilted decomposition column 13 from top to bottom with the hot air injected at the top. The temperature thus gradually increases from bottom to top. This method is referred to as the so-called inverse thermal gradient type.
- the decomposition column 27 is preferably tilted at an angle ⁇ of 25-30° as shown in FIG. 2 .
- the expanded plastic may quickly flow transversely and disappear in a short time.
- the gravity may make it hard to lift the expanded plastic f for a long distance from the surface of the dissolved plastic mp, so that the expanded plastic f may disappear again in a short time.
- the storage section 29 for the dissolved plastic mp is formed at a connection that connects a supplying column 28 and the decomposition column 27 in V shape.
- the supplying column 28 includes an inner column 20 and an outer column 21 .
- a hot air is supplied between those components via a pipe 22 to keep the temperature inside the inner column 20 at 200-350° C.
- the decomposition column 27 includes an inner column 25 , an outer column 17 , and a lead screw 24 .
- the lead screw 24 is provided in the decomposition column 27 such that the bottom of its shaft is rotatably supported at the bottom wall of the storage section 29 .
- a hot air producer supplies a heated air of 450-620° C. into between the inner column 25 and the outer column 17 via a pipe 26 c. This heated air then circulates through the decomposition column 27 by flowing down and exiting out of the pipe 26 b in the lower part of the decomposition column 27 and flowing into the pipe 26 a in the upper part.
- the hot air that thus circulates through the decomposition column 27 from top to bottom is able to increase the temperature in the decomposition column 27 from bottom to top.
- the lower part of the decomposition column 27 is held at 300-450° C. for the primary decomposition.
- the upper-part of the decomposition column 27 is heated to about 600° C. for the secondary decomposition.
- the expanded plastic f occurs in the storage section 29 .
- This expanded plastic f is then carried up in a good condition through the tilted decomposition column 27 and heated on the way to provide the decomposed gas.
- the decomposition column 27 and a supplying section 28 are connected in V shape and the dissolved plastic mp completely plugs the storage section 29 .
- the decomposed gas can thus safely prevent any backflow from the decomposition column 27 to the supplying column 28 . It is also prevented that an external air flows through the storage section 29 into the decomposition column 29 , thereby eliminating any danger of explosion.
- the plant for conversion into oil 30 includes, for example, a dissolution section 31 , a decomposition section 32 for primarily and secondarily decomposing the plastic dissolved in the dissolution section 31 , a dechlorination treatment section 33 for dechlorination in the treatment of the chlorine-including PVC, an off gas treatment section 34 for treating an off gas generated in the dissolution and decomposition of the plastic, and the first and second hot air producers 35 , 36 for generating a hot air which is a heat source for the dissolution and decomposition.
- the dissolution section 31 includes the first dissolution column 31 a which connects via an unheated section 410 to a hopper 41 into which plastic raw material drops, the second dissolution column 31 b which has its back end connected under the front end of the first dissolution column 31 a and intersects the first dissolution column 31 a at right angles, the third dissolution column 31 c which has its back end connected under the front end of the second dissolution column 31 b and intersects the second dissolution column 31 b at right angles, and the fourth dissolution column 31 d which has its back end connected under the front end of the third dissolution column 31 and intersects the third dissolution column 31 c at right angles.
- the hopper 41 includes a funnel-shaped casing 411 , a cover 412 covering the top surface of the casing 411 , a motor 413 centered on-the cover 412 , and a lead screw 414 including a rotating shaft 414 a which connects to the motor 413 and extends through the cover 412 into the casing 411 and a spiral blade 414 b attached to the rotating shaft 414 a.
- the spiral blade 414 b of the lead screw 414 is totally funnel shaped to the form of the casing 414 .
- a distance W of about 2 to 5 cm intervenes between the inner wall of the casing 414 and the periphery of the spiral blade 414 b.
- the motor 413 rotates the lead screw 414 at a predetermined speed to prevent the light plastic from blocking the hopper 41 .
- the heavy plastic drops through the distance W between the inner wall of the casing 414 and the periphery of the spiral blade 414 b.
- the lead screw 414 can reliably send the light plastic chips into the unheated section 410 .
- the unheated section 410 is column shaped and connected under the hopper 41 (see FIG. 17 ).
- a motor 42 connects to the end of the unheated section 410 .
- This motor 42 connects to a lead screw 137 common to a lead screw 137 in the dissolution column 31 a as described below.
- the motor 42 rotates the lead screw 137 to slowly forward the plastic chips sent from the hopper 41 and supply them into the dissolution column 31 a.
- a hot air does not heat the unheated section 410 , unlike the dissolution column 31 as described below.
- the attaching portion of the hopper 41 and the dissolution column 31 are therefore separated.
- spacing the dissolved portion of the plastic apart from the attaching portion of the hopper 41 is able to provide a longer undissolved portion of the plastic that presses forward the dissolved plastic.
- the dissolution column 31 includes a rectangular outer case 136 , and an inner column 131 in the outer case 136 (see FIG. 8 ).
- the inner column 131 contains a lead screw including a rotating shaft 133 and a spiral blade 132 around the rotating shaft 133 .
- the first dissolution column 31 a includes a lead screw with a greater pitch than the lead screws 137 in the other dissolution columns 31 b, 31 c, and 31 d . This is to provide a lower retention density of the plastic to give a lower resistance because of the first dissolution column 31 a having a lower set temperature than the other dissolution columns as described below.
- a motor rotates the lead screw 137 .
- a motor 42 rotates the first dissolution column 31 a (see FIGS. 4 and 5 )
- a motor 55 rotates the second dissolution column 31 b.
- a plurality of heatsink blades 134 reside around the inner. column 131 .
- a hot air space 135 intervenes between the inner column 131 and the outer case 136 .
- the first dissolution column 31 a is controlled to 190-200° C.
- the second dissolution column 31 b is controlled to 210-230° C.
- the third dissolution column 31 c is controlled to 230-260° C.
- the fourth dissolution column 31 d is controlled to 300-340° C.
- These four dissolution columns 31 a , 31 b, . . . , 31 d are thus arranged in a rectangle with the temperature increasing with each dissolution column.
- a sufficient retention time e.g. 20 minutes
- the first hot air producer 35 supplies a hot air via a pipe 70 to each dissolution column 31 .
- the producer 35 supplies the hot air from downstream to upstream of the column 31 in the carrying direction of the plastic.
- Each dissolution column 31 thus has an inverse thermal gradient.
- Blowers 56 , 57 , 58 (see FIG. 4 ), and 60 (see FIG. 7 ) circulate the hot air through each dissolution column 31 .
- a flue 59 connects to the first and second hot air producers 35 , 36 .
- the flue 59 includes branch pipes 59 a, 59 b, and an outlet 59 c, and is inverted U shaped (see FIG. 4 ).
- the decomposition section 32 includes the first stage decomposition column 47 controlled to 350-420° C. and the second stage decomposition column 48 adjacent to the first stage decomposition column 47 and controlled to 450-580° C. (see FIG. 7 ).
- the decomposition columns 47 , 48 are tilted at 25-30° relative to the horizontal.
- the fourth dissolution column 31 d has an end that connects into the first stage decomposition column 47 . This connection forms the storage section for the dissolved plastic.
- the first stage decomposition column 47 includes two unit decomposition columns 47 a, 47 b, which are divided by a partition 256 into two rows of left and right (see FIG. 9 ).
- the unit decomposition columns 47 a, 47 b each include an inner column 255 , a plurality of heatsink fins 253 around the inner column 255 , a lead screw 150 , and a heat space 254 into which a hot air is sent.
- Each lead screw 150 includes a rotation shaft 251 and a spiral blade 252 . Motors 51 and 52 rotate the lead screws 150 (see FIG. 5 ).
- the second stage decomposition column 48 has almost the same structure as the first stage decomposition column 47 .
- the second stage decomposition column 48 has unit decomposition columns 48 a , 48 b (see FIG. 6 ) which each have an inner column 148 .
- the inner column 148 contains a lead screw 149 .
- Motors 53 , 54 (see FIGS. 5 and 7 ) rotate the lead screws 149 slowly (4-5 revolutions per minute).
- the inner column 255 in the first stage decomposition column 47 has at its upper end a superheat 151 for heating to 580-620° C. the decomposed gas flowing through the superheat 151 (see FIG. 7 ).
- the decomposed gas that has been secondarily decomposed in the first stage decomposition column 47 exits through the superheat 151 and pipe 49 , and is sent to the condenser 37 (see FIG. 5 ) via a scrubber 60 for alkali cleaning.
- the condenser 37 then cools the decomposed gas into oil, which is stored through a pipe 46 in an oil storage tank 42 . Some of the oil stored in the oil storage tank 42 is supplied to the hot air producers 35 , 36 via a service tank ST 1 .
- valve 49 a On the way of the pipe 49 a valve 49 a resides for controlling the flow rate of the decomposed gas through the pipe 49 .
- the condenser 37 needs to receive only the light decomposed gas that has been completely secondarily decomposed in the first stage decomposition column 47 .
- the decomposed gas derived from the pipe 49 may contain incompletely secondarily decomposed gas that is slightly heavy. For a smaller amount of the decomposed gas derived from the pipe 49 , the incompletely decomposed gas cannot go up the rising portion of the pipe 49 and will be returned into the first stage decomposition column 47 and sent into the second stage decomposition column 48 via the falling column 120 .
- the decomposed gas will be derived more strongly so that the incompletely decomposed gas can go up the rising portion of the pipe 49 and will be sent to the condenser 37 .
- the valve 49 a can thus adjust the amount of the decomposed gas derived from the pipe 49 to prevent the incompletely decomposed gas from being sent to the condenser 37 .
- the first stage decomposition column 47 is controlled to 350-420° C. as described above.
- the first stage decomposition column 47 is thus able to primarily and secondarily decompose the oil component corresponding to gasoline with a low decomposition temperature, and some of the oil component corresponding to coal oil and diesel oil.
- the superheat 151 can completely secondarily decompose the insufficiently decomposed gases.
- the condenser 37 can cool into oil the decomposed gases that have been secondarily decomposed as described above.
- the pipe 46 with a pump P can suck the gases that have been insufficiently converted into oil by the condenser 37 and store them in the oil storage tank 42 as an off gas.
- the expanded plastic component that has been incompletely secondarily decomposed in the first stage decomposition column 47 is supplied to the bottom of the second stage decomposition column 48 via the falling column 120 .
- the lead screw 149 in the second stage decomposition column 48 will then send up the expanded plastic component at an angle.
- the second stage decomposition column 48 is controlled to a temperature of 450-580° C.
- the second decomposition column 48 can thus completely secondarily decompose the residual portion of the component corresponding to coal oil and diesel oil, and the crude oil component.
- the residuals such as metal and dirt that have been dropped together with the plastic will be stored in a sludge tank 40 via a sludge pipe 40 a.
- the sludge tank 40 contains water 40 b.
- a metal gauge 40 c resides in the water 40 b, which collects the residuals. Taking the metal gauge 40 c out of the sludge tank 40 can remove the residuals from the sludge tank 40 .
- a cover 40 d with a partial opening 40 e covers the top surface of the sludge tank 40 .
- Inactive gas 40 f that is heavier than the air, such as carbon dioxide gas, fills the space above the water 40 b in the sludge tank 40 .
- the sludge pipe 40 a has its bottom in the inactive gas 40 f.
- a gas cylinder 40 g connects to the sludge tank 40 .
- the gas cylinder 40 g can supply into the sludge tank 40 the inactive gas 40 f, some of which overflows the opening 40 e.
- the inactive gas 40 f in which the sludge pipe 40 a has its bottom can effectively prevent the air from flowing into the second stage decomposition column 48 from the sludge pipe 40 a, thereby eliminating any danger of explosion.
- the water 40 b in which the sludge pipe 40 a has its bottom would float by the buoyancy the light residuals that may block the bottom of the sludge pipe 40 a.
- the inactive gas 40 f in which the sludge pipe 40 a has its bottom can prevent the above described problem and allow for the smooth falling of the residuals into the water 40 b.
- the second hot air producer 36 supplies a hot air via pipes 71 , 71 a, and 71 b (see FIG. 5 ) to the upper parts of the first and second stage decomposition columns 47 , 48 .
- the blowers 170 , 171 can circulate the hot air through the decomposition columns 47 , 48 by drawing the air out of the bottoms and returning it to the tops.
- the decomposition columns 47 , 48 thus have an inverse thermal gradient in which the temperature decreases from top to bottom.
- the first hot air producer 35 supplies to the dissolution section 31 a hot air that is circulated, for example, by the blower 60 through the fourth dissolution column 31 d (see FIG. 7 ).
- the inner column 148 of the second stage decomposition column 48 has at its upper end a pipe 50 that connects to a condenser 38 via a scrubber 61 for alkali cleaning (see FIG. 5 ).
- the decomposed gas that has been decomposed in the second stage decomposition column 48 goes through the pipe 50 to the scrubber 61 and into the condenser 38 .
- the condenser 38 then cools the decomposed gas into oil, which goes through a pipe 86 to an oil storage tank 43 . Some of this oil goes through a service tank ST 2 to the above described first and second hot air producers 35 , 36 .
- a cooling tower CT cools the above described condensers 37 , 38 (see FIG. 3 ).
- the first and second stage decomposition columns 47 , 48 include pipes 101 , 102 connected thereto, both of which connect to a collecting pipe 100 .
- the exhaust from the first and second stage decomposition columns 47 , 48 goes through the pipes 101 , 102 to the collecting pipe 100 into the outside.
- the pump P collects through the pipe 86 into the oil storage tank 43 a gas that has not been converted into oil in the condenser 38 which connects to the above described second stage decomposition column 48 .
- the extendable column 700 includes a bellows portion 701 and a sliding portion 702 (see FIG. 19 ).
- the bellows portion 701 includes a bellows 703 and a bellows inner column 704 located in the bellows 703 .
- the bellows inner column 704 has a longer full length than the bellows 703 .
- the bellows 703 and bellows inner column 704 are arranged with their ends aligned on one side.
- the bellows inner column 704 extends beyond the other end of the bellows 703 .
- a support column 705 resides around the extended bellows inner column 704 .
- the support column 705 has an inner diameter that is slightly larger than the outer diameter of the bellows inner column 704 .
- the inner surface of the support column 705 and the outer surface of the bellows inner column 704 provide sliding surfaces.
- an inner column 706 with the same diameter as the bellows inner column 704 resides on the portion of the support 705 on which the bellows inner 704 does not reside.
- Formed on the butt side ends between the bellows inner column 704 and the inner column 706 are corresponding shoulders 704 a, 706 a. Opposite surfaces of the shoulders 704 a, 706 a provide sliding surfaces.
- the extendable column 700 provided in a part of the dissolution column 31 and decomposition columns 47 , 48 thus serves to absorb the expansion of the dissolution column 31 and decomposition columns 47 , 48 that are heated and expanded.
- the extendable column 700 provided in a part of the first dissolution column 31 a can reduce the bellows 703 to reduce the bellows inner column 704 toward the sliding portion 702 to absorb the expansion of the first dissolution column 31 a.
- the sliding portion 702 includes the bellows inner column 704 with its sliding area outside the bellows 701 , and the support column 705 with the diameter larger than the bellows inner column 704 .
- the bellows inner column 704 can therefore have a greater thickness without reducing the inner diameter of the bellows inner column 704 . This can prevent the deformation of the extendable column 700 , therefore the damage of the bellows 703 due to the deformed extendable column 700 , and the fire due to the decomposed gases or the like flowing out of the damaged portion of the bellows 703 .
- the dechlorination treatment system 33 will now be described in detail.
- Pipes 75 , 76 , and 77 extending from the upper surface of the dissolution columns 31 a, 31 b, and 31 c of the dissolution section 31 connect to a pipe 78 (see FIG. 5 ).
- the pipe 78 in turn connects to the first separator 37 (see FIG. 10 ).
- the first separator 37 can separate the hydrogen chloride gas generated in the dissolution sections 31 a , 31 b, and 31 c from the small amount of decomposed gas contained in the hydrogen chloride gas.
- the separator 37 includes a cooling coil 301 on the top. The hydrogen chloride gas flowing through the pipe 78 will be cooled through the cooling coil 301 and released in the lower part of the first separator 37 below the cooling coil 301 .
- the hydrogen chloride gas goes through the cooling coil 301 , the upper part of the first separator 37 , and a pipe 79 into the second separator 38 that has the same structure as the first separator 37 .
- the hydrogen chloride gas goes into the third separator 39 that has the same structure as the first and second separators 37 , 38 .
- the hydrogen chloride gas goes through a pipe 81 to the lower part of the reactor 300 .
- a plurality of these separators 37 , 38 , and 39 can completely separate the hydrogen chloride gas from the decomposed gas.
- the reactor 300 includes a stirring bar 306 with blades 308 .
- a hydrated lime tank 83 connects to the upper part of the reactor 300 .
- a heating column 305 resides around the hydrated lime tank 83 to dry the hydrated lime in the hydrated lime tank 83 .
- a lead screw 303 resides at the lower part of the hydrated lime tank 83 .
- a motor 304 rotates this lead screw 303 .
- a lead screw 309 resides at the bottom of the reactor 303 .
- a motor 310 rotates this lead screw 309 .
- a heating column 313 heats the surrounding area of the lead screw 309 to dry and remove the water generated during the reaction in the reactor.
- a calcium chloride tank 312 contains the calcium chloride generated during the reaction in the reactor 309 .
- Temperature sensors S 1 , S 2 , and S 3 reside at appropriate positions in the height direction of the reactor 300 . The temperature sensors S 1 , S 2 , and S 3 detect the reaction heat. These reactor heat detection signals can control the rotation of the motor 304 for the hydrated lime tank 83 and the motor 310 for the lead screw 309 for evacuating the reactor 300 .
- the stirring bar 306 in the reactor 300 consistently rotates, and a large amount of hydrogen chloride gas flowing into the reactor 300 can facilitate the reaction to generate a large amount of heat.
- the temperature sensor S 3 at the highest position that detects reaction heat equal to or greater than a predetermined value will cause the lead screw 303 for the hydrated lime tank 83 to rotate to send a large amount of the hydrated lime into the reactor 300 . Then the reaction proceeds to generate less reaction heat and slightly reduce the temperature.
- the temperature sensor S 2 at an intermediate position detects a temperature in a predetermined range, the hydrated lime is accordingly supplied. Then the reaction further proceeds to slow down.
- the temperature sensor S 1 at the lowest position detects a predetermined temperature, it determines that the reaction stops and rotates the lead screw 309 for evacuating the reactor 300 and collects the calcium chloride generated into the calcium chloride tank 312 . After the calcium chloride generated being collected, when the reaction starts again, the temperature sensor S 1 detects the starting of the reaction and causes the lead screw 303 to rotate to send the hydrated lime from the hydrated lime tank 83 into the reactor 300 . As the temperature sensors S 2 , S 3 detect the reaction heat in sequence, more hydrated lime will be supplied. As the reaction heat decreases, less hydrated lime will be supplied, and the above described procedure will be repeated.
- the hydrogen chloride gas usually needs a solvent to react with a dry neutralizing agent.
- the water generated in the reaction of the hydrogen chloride gas with the hydrated lime can provide the solvent which can facilitate the neutralization reaction.
- a vacuum pump 314 resides to evacuate water that is generated as vapor in this reaction and draw the hydrogen chloride gas into the reactor 300 .
- a relief valve 315 for air inflow resides on the inlet side of the vacuum pump 314 .
- a scrubber 317 for alkali cleaning resides to remove the hydrogen chloride gas that has been insufficiently reacted in the reactor 300 .
- the off gas treatment system 34 will now be described.
- FIG. 11 shows a schematic diagram of the off gas treatment system 34 .
- the off gas treatment system 34 includes a casing 236 .
- a burner 234 is consistently connected to the casing 236 , which is heated to about 1200° C.
- the above-described casing 236 contains a plurality of ceramic prisms 238 , 238 , . . . , 238 .
- These ceramic prisms can catalytically crack an off gas in ⁇ fraction (1/100) ⁇ - ⁇ fraction (2/100) ⁇ seconds that flows in through the inlet 235 connected to the above described oil storage tanks 42 , 43 .
- the ceramic prisms can thus convert the off gas into a simple oxide such as CO 2 , NO x , and H 2 O.
- the heat energy generated in this process goes through the outlet 237 into the first and second hot air producers 35 , 36 .
- the off gas is an endocrine disrupter, such as acetaldehyde, which has not been converted into oil in the condensers 37 , 38 .
- the oil storage tanks 42 , 43 send it to the off gas treatment system 34 .
- the condensers 37 , 38 may directly send the off gas to the off gas treatment system 34 .
- a number of temperature sensors S, S, . . . S reside on each dissolution column in the dissolution section 31 and each tilted column in the decomposition section 32 .
- Each sensor S connects to a controller 511 .
- This controller 511 can control the open/close of a valve 513 connected to a carbon dioxide gas cylinder 512 .
- This carbon dioxide gas cylinder 512 connects to a hot air circulation path P through which the first and second hot air producers 35 , 36 can send the hot air into the dissolution section 31 and decomposition section 32 .
- the controller 511 opens the valve 513 to supply the carbon dioxide gas through the hot air circulation path Q into the dissolution section 31 and decomposition section 32 , if the temperature sensor S detects an abnormal temperature due to such as accidents. This can cool the dissolution section 31 and decomposition section 32 , and stop the operation of the plant for conversion into oil 30 .
- An accumulation facility A for the plastic to be treated has at the top a suction unit 514 with a suction fan 514 a.
- the suction unit 514 particularly sucks an air with an odor caused by the plastic waste and sends it to the hot air producer 36 for the deodorization by combustion.
- Plastic chips P crushed by a crusher 515 are dried in a drier 516 with the hot air from the hot air producer 36 .
- the dried plastic chips P are then sent to the hopper 41 .
- the drier 516 in which the hot air dries the plastic chips P may be filled with an odor.
- the air with an odor in the drier 516 is sent to the hot air producer 35 for treatment after a cyclone 517 removes fine particles mixed in the air.
- the off gas treatment section 34 for the off gas treatment may decompose the air with an odor.
- the hot air producer 35 , 36 or the off gas treatment section 34 therefore, may treat the air with an odor.
- the embodiments described above use two stages of the decomposition columns.
- the dissolution section 200 may be provided as follows: the second stage decomposition column 48 may precede the third stage decomposition column 210 that has the same structure and the same tilting angle as the second stage decomposition column 48 , as shown in FIG. 12 .
- the temperature range may be of 350-400° C. in the first stage decomposition column, 400-480° C. in the second stage decomposition column, and 480-580° C. in the third stage decomposition column.
- Such three stages of the decomposition columns can provide a more moderate distribution of the decomposition temperature and a longer decomposition time, thereby making it possible to adapt to any change in the decomposition condition such as the plastic specific gravity, and to ensure the reliable secondary decomposition.
- the upper end of the second stage decomposition column 48 connects, via a falling column 218 , to the bottom of the third stage decomposition column 210 tilted at the same angle.
- the second stage decomposition column 48 sends the undecomposed expanded plastic and decomposed gas that have not been extracted in the column 48 into the third stage decomposition column 210 through the falling column 218 .
- the third stage decomposition column 210 can secondarily decompose the undecomposed expanded plastic and decomposed gas.
- the secondarily decomposed gas goes through a scrubber 216 for alkali cleaning into a condenser 213 which cools the decomposed gas into oil corresponding to A crude oil.
- This oil goes through a pipe 214 into the oil storage tank 215 where the oil is stored.
- a blower 221 connects to the third stage decomposition column from the top to form an inverse thermal gradient.
- the residuals go through a sludge pipe 219 into a sludge tank 220 filled with water where the residuals are stored.
- a pump P sucks the decomposed gas that has not been converted into oil in the above described condenser 213 of the third stage decomposition column 210 .
- the pump P then sends the decomposed gas through the pipe 214 into the oil storage tank 215 where the gas is stored.
- the first and second stage decomposition columns 47 , 48 draw the secondarily decomposed gas out of the top for conversion into oil.
- a superheat 151 , 152 decompose the gas that has been insufficiently secondarily decomposed.
- the second stage decomposition column can provide the decomposed gas that corresponds to a component of diesel oil, coal oil, and some of the crude oil.
- the third stage decomposition column can decompose the residual component corresponding to the A crude oil. More than three stages decomposition columns may be used.
- the embodiment shown in FIG. 312 uses a dissolution section 200 that is formed vertically (perpendicularly). Specifically, the first, second, and third dissolution columns 201 , 202 , and 203 are connected perpendicularly via connections 204 , 205 , respectively.
- the plastic from the hopper 41 goes right through the first dissolution column 201 , left through the second dissolution column 202 , and right through the third dissolution column 203 before being supplied to the bottom of the first stage decomposition column 47 .
- a motor 208 rotates a lead screw 207 of the third dissolution column 203 at the lowest stage. The rotation of the motor 208 also rotates a lead screw 206 of the first dissolution column 201 via a chain 209 .
- the rotation of the lead screw 206 in turn rotates a lead screw 212 of the second dissolution column 202 via gears G 1 , G 2
- a blower 213 circulates a hot air up through the dissolution section 200 by drawing the air out of the top at a lower temperature to the bottom at a higher temperature via a pipe 222 .
- a heating medium heating system 600 supplies a heating medium which heats the first to fourth dissolution columns 31 a, 31 b, . . . , 31 d.
- the heating medium here refers to a liquid heating medium such as various types of thermal oil.
- the heating medium heating system 600 heats the heating medium to a predetermined temperature and sends the medium through a heating medium pipe 601 into a heating medium space 135 ′ of the dissolution column 31 .
- the heating medium space 135 intervenes between an inner wall 131 and an outer case 136 , as for the above described hot air space 135 .
- a circulation pump 602 circulates the heating medium through the heating medium space 135 from downstream to upstream.
- the first dissolution column 31 a is controlled to 190-200° C., the second dissolution column 31 b to 210-230° C., the third dissolution column 31 c to 230-260° C., and the fourth dissolution column 31 d to 300-340° C., as in the above described hot air heating.
- the heating medium thus used instead of the hot air can a) greatly improve the heat transfer efficiency, b) reduce the temperature drop in the dissolution column 31 when the plant stopped, because the heating medium cools less rapidly than the hot air, thereby allowing the plant to start up more quickly, and c) prevent the fire even if the inner column 131 of the dissolution column 31 is damaged.
- the heating medium is used only for heating the dissolution column 31 because the heating medium generally operates at 350 #1# or less. Any other suitable heating medium, however, can be selected also to heat the decomposition columns 47 , 48 . Depending on the temperature at which the heating medium operates, the heating medium may only heat the dissolution columns 31 that are controlled to lower temperatures (such as first, second, and third dissolution columns 31 a, 31 b, and 31 c ).
- a connection 500 connects the fourth dissolution column 31 d and the lower part of the first stage decomposition column 47 .
- the column 31 d supplies the dissolved expanded plastic into the bottom of the inner column 255 in the first stage decomposition column 47 .
- the above described connection 500 may receive vegetable or animal cooking oil or their waste oil or the like stored in a tank 502 .
- Each dissolution column primarily and secondarily decomposes the mixture of the oil and expanded plastic. This can collect reformed oil through chemical decomposition reaction.
- plastics such as polyethylene, polypropylene, polystyrene, ABS resin, and acrylic resin are thermally decomposed into oil (90%) that is collected as the generated oil, an off gas (7-8%) that is treated in the off gas treatment system 34 , and carbide (2-3%) that is collected as the residual into the residual tank 40 .
- Polyvinyl chloride is neutralized by calcium hydroxide into calcium chloride (about 58%), and the residual (about 42%) is thermally decomposed, but only about 30% is converted into oil and collected.
- the method and plant for converting plastic into oil according to the present invention are useful as the method and plant for converting plastic into oil for collecting the oil from the plastic waste.
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Abstract
Description
- The present invention relates to a method and a plant for converting plastic into oil for collecting the oil from the plastic.
- Various plants for collecting oil from plastic waste have been proposed, none of them, however, has sufficiently decomposed the plastic, and actually no plants are in practical operation.
- The present applicants previously developed a plant for conversion into oil that has a compact and simple structure of an inverse thermal gradient type, which is disclosed in Japanese application patent laid-open publication No. 2000-16774.
- There have been problems, however, with this plant for conversion into oil, including: 1) the plant can reliably convert a small amount of plastic into oil, but the plant cannot completely convert a large amount of plastic into oil, 2) the plant cannot sufficiently treat a hydrogen chloride gas that is generated in a dissolution section in dissolving PVC (polyvinyl chloride) plastic, and 3) the plant cannot sufficiently treat an off gas that has not been converted into oil.
- The present invention has been mainly made in light of these problems and a primary object of the present invention is to provide a method and a plant for conversion into oil, which are able to convert a large amount of plastic into oil, to treat a hydrogen chloride gas, and to completely treat an off gas.
- The method for conversion into oil according to the present invention comprises heating and dissolving the plastic into expanded plastic, and removing the expanded plastic, heating and depolymerizing it, and cooling it into oil. The expanded plastic may preferably be removed by being lifted at an angle, preferably at an angle of 25-30° relative to the horizontal. The expanded plastic may preferably be heated with being lifted at an angle and the expanded plastic may preferably be heated to higher temperatures at higher positions. The dissolved plastic may preferably be added with vegetable oil or animal oil or mineral oil and heated to generate expanded plastic of their mixture.
- The method for conversion into oil according to the present invention may preferably comprising separating a hydrogen chloride gas generated in dissolving the plastic from other decomposed gases, then reacting the hydrogen chloride gas with hydrated lime, and collecting it as calcium chloride. An off gas not converted into oil may preferably be treated by catalytically cracking the off gas with a hot ceramic.
- A plant for conversion into oil according to the present invention comprises a dissolution section for heating and dissolving the plastic into expanded plastic, and a decomposition section for removing the expanded plastic, heating and depolymerizing it, and cooling it into oil. In this plant for conversion into oil, the decomposition section may preferably comprise a removal means for removing the expanded plastic by lifting it at an angle, preferably at an angle of 25-30° relative to the horizontal. The decomposition section may preferably comprise a heating means for heating the expanded plastic with lifting it at an angle and for heating the expanded plastic to higher temperatures at higher positions. The plant may preferably comprise an oil injection means for injecting vegetable oil or animal oil or mineral oil into a connection between the dissolution section and the decomposition section. The dissolution section may preferably comprise a plurality of dissolution columns with different temperature ranges. The decomposition section may preferably comprise a plurality of tilted decomposition columns with different temperature ranges.
- The plant for conversion into oil according to the present invention may preferably comprise a dechlorination system for treating a hydrogen chloride gas generated in the dissolution section. This dechlorination system may preferably comprise a separator for separating the hydrogen chloride gas from other decomposed gases, and a reactor for reacting the hydrogen chloride gas separated by the separator with hydrated lime into calcium chloride. The plant may preferably comprise an off gas treatment system for treating an off gas not converted into oil after cooling in the decomposition section by catalytically cracking the off gas with a hot ceramic.
- The plant for conversion into oil according to the present invention may preferably comprise a residual collection means at the top of the final stage decomposition column of the multistage decomposition columns. The residual collection means may preferably comprise a column with its upper opening at the top of the final stage decomposition column and its lower opening in an atmosphere of an inactive gas heavier than the air.
- The plant for conversion into oil according to the present invention may preferably comprise a hopper for storing and supplying the plastic into the dissolution section, and the hopper may preferably comprise a lead screw with a spiral blade. The plant may preferably comprise an unheated section formed as an unheated area of a predetermined length between the hopper and the dissolution section. The plurality of dissolution columns each may preferably comprise a lead screw with a spiral blade for carrying the plastic, and a beginning dissolution column of the plurality of dissolution columns may preferably comprise the lead screw blade with a greater pitch than the lead screws blades in other dissolution columns.
- In the plant for conversion into oil according to the present invention, the dissolution section and the decomposition section each may preferably comprise: an inner column; an outer column around the inner column; a hot air space between the inner column and the outer column and through which an hot air circulates; and a temperature sensor for detecting a temperature in the dissolution section or the decomposition section, and the plant may preferably further comprise a carbon dioxide gas supplying system for supplying the carbon dioxide gas into the hot air space if the temperature sensor detects an abnormal temperature equal to or greater than a predetermined temperature.
- In the plant for conversion into oil according to the present invention, the dissolution section and the decomposition section each may preferably comprise: an inner column; an outer column around the inner column; and a hot air space between the inner column and the outer column and through which an hot air circulates, and the plant may preferably further comprise: a hot air production system for generating by combustion the hot air to be supplied into the hot air space; and a drying system for drying the plastic to be supplied into the dissolution furnace, and an air in the drying system may preferably be supplied into the hot air production system to be deodorized by combustion. The air in the drying system may preferably be supplied into the off gas treatment system to be deodorized by being catalytically cracked with a hot ceramic.
- In the plant for conversion into oil according to the present invention, an extendable column which is extendably formed may preferably be used in a part of the dissolution column includes, and the extendable column may preferably comprise: an inner column; a bellows around the inner column which has one end fixed on the inner column and an other end slidable relative to the inner column; and an outer column which is fixed on the other end of the bellows and slidably contains the inner column.
- In the plant for conversion into oil according to the present invention, the dissolution section may preferably comprise: an inner column; an outer column around the inner column; and a heating medium space between the inner column and the outer column and through which a liquid heating medium circulates, and the plant further may preferably comprise a heating medium supplying system for supplying the liquid heating medium into the heating medium space.
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FIG. 1 shows a schematic diagram of the basic principle of the present invention. -
FIG. 2 shows a schematic diagram of an embodiment according to the basic principle of the present invention. -
FIG. 3 shows a schematic perspective view of a plant of conversion into oil of an embodiment according to the present invention. -
FIG. 4 shows a schematic front view of a plant of conversion into oil of an embodiment according to the present invention. -
FIG. 5 shows a schematic plan view of a plant of conversion into oil of an embodiment according to the present invention. -
FIG. 6 shows a schematic diagram ofFIG. 5 . -
FIG. 7 shows a schematic diagram ofFIG. 4 . -
FIG. 8 shows a schematic transverse cross sectional view of a dissolution column. -
FIG. 9 shows a schematic transverse cross sectional view of a decomposition column. -
FIG. 10 shows a schematic diagram of a dechlorination treatment section. -
FIG. 11 shows a schematic diagram of an off gas treatment section. -
FIG. 12 shows a schematic diagram of another embodiment. -
FIG. 13 shows a schematic diagram of a connection between a dissolution section and a decomposition section. -
FIG. 14 shows recovery rates for different plastics to be treated. -
FIG. 15 shows a schematic illustration of how to lift expanded plastic. -
FIG. 16 shows a schematic transverse cross-sectional view of a hopper. -
FIG. 17 shows a schematic perspective view of an unheated section. -
FIG. 18 shows a schematic diagram of a sludge tank. -
FIG. 19 shows a schematic diagram of an extendable column. -
FIG. 20 shows a schematic diagram of an accident avoidance system and a deodorant system. -
FIG. 21 shows a schematic diagram of another embodiment. - The embodiments of the present invention will be described below referring to the drawings.
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FIG. 1 shows a conceptual diagram illustrative of the basic principle of a method for converting plastic into oil according to the present invention. Plastic raw-material is dissolved at a temperature of 200-350° C. and is stored in astorage section 1. Adecomposition column 13 lifts the plastic that is dissolved (dissolved plastic) at an angle. - The
decomposition column 13 includes aninner column 2, anouter column 6 which forms ahot air space 4 around theinner column 2, and alead screw 7. Thelead screw 7 includes a rotatingshaft 14 and aspiral blade 8. Amotor 12 rotates thelead screw 7 at a speed of 4-5 revolutions per minute. Apipe 10 supplies a hot air into thehot air space 4 to hold the temperature of theinner column 2 at 350-620° C. for gasification and depolymerization of plastic. - The
lead screw 7 carries through theinner column 2 the dissolved plastic which is primarily decomposed (into the first heavy gas state that is gasified from the dissolved state) in the lower part of thedecomposition column 13 to provide a primarily decomposed gas. Thelead screw 7 carries the primarily decomposed gas at a low speed to the upper part of thedecomposition column 13. The primarily decomposed gas is then secondarily decomposed (into a state that is depolymerized from the plastic and can be cooled into oil) in theinner column 2 which is held at 350-620° C. by the hot air supplied from apipe 15, to provide a light secondarily decomposed gas. - One decomposition column is enough to sufficiently secondarily decompose at the upper part of the decomposition column all oil components included in the plastic raw material. Two decomposition columns may be used of which the first stage decomposition column connects to the
storage section 1 and the second stage decomposition column connects to the first stage decomposition column. - An
outer case 5 resides outside thestorage section 1 to form ahot air space 3 into which a hot air is sent. The plastic supplied into the storage section is heated to 200-350° C. to provide dissolved plastic mp with foamed plastic (expanded plastic) f formed on its surface. This expanded plastic f is heated with being lifted at an angle by alead screw 7 which has itstip 14 a immersed in the dissolved plastic mp. This can provide a larger contact area between the expanded plastic f and the heat to ensure the decomposition (depolymerization) of the expanded plastic f into the secondarily decomposed gas. Apipe 9 collects the secondarily decomposed gas, which is then cooled into oil and stored in an oil storage tank. - The expanded plastic f is preferably lifted at a speed of 30-60 cm/min. A lower speed will give less carrying efficiency and a higher speed will give insufficient decomposition. For example, the
lead screw 7 lifts spirally the expanded plastic f as shown inFIG. 15 , preferably by moving it spirally at a speed of 30-60 cm/min. This speed can be adjusted by, for example, the pitch p of thelead screw 7. The expanded plastic f is thus carried at the above-described speed and heated slowly through theinner column 2 to be sufficiently decomposed (depolymerized) in the primary and secondary decomposition temperature areas. The expanded plastic f is preferably heated for about 14-15 minutes before it is completely secondarily decomposed at about 600° C. - Different kinds of plastic raw material need to be treated at different temperatures. The
storage section 1 is preferably held at temperatures (200-350° C.) at which the dissolved plastic mp can be expanded. For good decomposition, it is important to have a low temperature gradient to keep the expanded condition for a long time and to have a large contact area with the heat. For this purpose, thedecomposition column 13 is preferably tilted relative to the horizontal. A hot air circulates through the tilteddecomposition column 13 from top to bottom with the hot air injected at the top. The temperature thus gradually increases from bottom to top. This method is referred to as the so-called inverse thermal gradient type. - To keep the good expanded plastic f for a long time, the
decomposition column 27 is preferably tilted at an angle θ of 25-30° as shown inFIG. 2 . For thedecomposition column 27 tilted at an angle θ of less than 25°, the expanded plastic may quickly flow transversely and disappear in a short time. For thecolumn 27 tilted at an angle θ of higher than 30°, the gravity may make it hard to lift the expanded plastic f for a long distance from the surface of the dissolved plastic mp, so that the expanded plastic f may disappear again in a short time. - In
FIG. 2 , thestorage section 29 for the dissolved plastic mp is formed at a connection that connects a supplyingcolumn 28 and thedecomposition column 27 in V shape. The supplyingcolumn 28 includes aninner column 20 and anouter column 21. A hot air is supplied between those components via apipe 22 to keep the temperature inside theinner column 20 at 200-350° C. - The
decomposition column 27 includes aninner column 25, anouter column 17, and alead screw 24. Thelead screw 24 is provided in thedecomposition column 27 such that the bottom of its shaft is rotatably supported at the bottom wall of thestorage section 29. A hot air producer supplies a heated air of 450-620° C. into between theinner column 25 and theouter column 17 via apipe 26 c. This heated air then circulates through thedecomposition column 27 by flowing down and exiting out of thepipe 26 b in the lower part of thedecomposition column 27 and flowing into thepipe 26 a in the upper part. The hot air that thus circulates through thedecomposition column 27 from top to bottom is able to increase the temperature in thedecomposition column 27 from bottom to top. The lower part of thedecomposition column 27 is held at 300-450° C. for the primary decomposition. The upper-part of thedecomposition column 27 is heated to about 600° C. for the secondary decomposition. - The expanded plastic f occurs in the
storage section 29. This expanded plastic f is then carried up in a good condition through the tilteddecomposition column 27 and heated on the way to provide the decomposed gas. Thedecomposition column 27 and a supplyingsection 28 are connected in V shape and the dissolved plastic mp completely plugs thestorage section 29. The decomposed gas can thus safely prevent any backflow from thedecomposition column 27 to the supplyingcolumn 28. It is also prevented that an external air flows through thestorage section 29 into thedecomposition column 29, thereby eliminating any danger of explosion. - The plant for conversion into oil using the above described method for converting plastic into oil will be described below.
- In
FIGS. 3-7 , the plant for conversion intooil 30 according to the present invention includes, for example, adissolution section 31, adecomposition section 32 for primarily and secondarily decomposing the plastic dissolved in thedissolution section 31, adechlorination treatment section 33 for dechlorination in the treatment of the chlorine-including PVC, an offgas treatment section 34 for treating an off gas generated in the dissolution and decomposition of the plastic, and the first and secondhot air producers - As shown in
FIG. 6 , thedissolution section 31 includes thefirst dissolution column 31 a which connects via anunheated section 410 to ahopper 41 into which plastic raw material drops, thesecond dissolution column 31 b which has its back end connected under the front end of thefirst dissolution column 31 a and intersects thefirst dissolution column 31 a at right angles, thethird dissolution column 31 c which has its back end connected under the front end of thesecond dissolution column 31 b and intersects thesecond dissolution column 31 b at right angles, and thefourth dissolution column 31 d which has its back end connected under the front end of thethird dissolution column 31 and intersects thethird dissolution column 31 c at right angles. The first toforth dissolution columns dissolution columns 31 a-31 d may also be connected horizontally. - As shown in
FIG. 16 , thehopper 41 includes a funnel-shapedcasing 411, acover 412 covering the top surface of thecasing 411, amotor 413 centered on-thecover 412, and alead screw 414 including arotating shaft 414 a which connects to themotor 413 and extends through thecover 412 into thecasing 411 and aspiral blade 414 b attached to therotating shaft 414 a. Thespiral blade 414 b of thelead screw 414 is totally funnel shaped to the form of thecasing 414. A distance W of about 2 to 5 cm intervenes between the inner wall of thecasing 414 and the periphery of thespiral blade 414 b. Themotor 413 rotates thelead screw 414 at a predetermined speed to prevent the light plastic from blocking thehopper 41. The heavy plastic drops through the distance W between the inner wall of thecasing 414 and the periphery of thespiral blade 414 b. Thelead screw 414 can reliably send the light plastic chips into theunheated section 410. - The
unheated section 410 is column shaped and connected under the hopper 41 (seeFIG. 17 ). Amotor 42 connects to the end of theunheated section 410. Thismotor 42 connects to alead screw 137 common to alead screw 137 in thedissolution column 31 a as described below. Themotor 42 rotates thelead screw 137 to slowly forward the plastic chips sent from thehopper 41 and supply them into thedissolution column 31 a. A hot air does not heat theunheated section 410, unlike thedissolution column 31 as described below. The attaching portion of thehopper 41 and thedissolution column 31 are therefore separated. This can prevent the plastic from starting to dissolve near the attaching portion of thehopper 41 or the viscous resistance of the dissolved plastic from stopping the rotation of thelead screw 137. Specifically, spacing the dissolved portion of the plastic apart from the attaching portion of thehopper 41 is able to provide a longer undissolved portion of the plastic that presses forward the dissolved plastic. - The
dissolution column 31 includes a rectangularouter case 136, and aninner column 131 in the outer case 136 (seeFIG. 8 ). Theinner column 131 contains a lead screw including arotating shaft 133 and aspiral blade 132 around therotating shaft 133. Thefirst dissolution column 31 a includes a lead screw with a greater pitch than the lead screws 137 in theother dissolution columns first dissolution column 31 a having a lower set temperature than the other dissolution columns as described below. A motor rotates thelead screw 137. For example, amotor 42 rotates thefirst dissolution column 31 a (seeFIGS. 4 and 5 ), and amotor 55 rotates thesecond dissolution column 31 b. - A plurality of
heatsink blades 134 reside around the inner.column 131. Ahot air space 135 intervenes between theinner column 131 and theouter case 136. Thefirst dissolution column 31 a is controlled to 190-200° C., thesecond dissolution column 31 b is controlled to 210-230° C., thethird dissolution column 31 c is controlled to 230-260° C., and thefourth dissolution column 31 d is controlled to 300-340° C. These fourdissolution columns first dissolution column 31 a to prevent the adhesion of the plastic to therotating shaft 133 near thehopper 41, and (d) to provide a shorter installation length of the entire plant. - The first
hot air producer 35 supplies a hot air via apipe 70 to eachdissolution column 31. Theproducer 35 supplies the hot air from downstream to upstream of thecolumn 31 in the carrying direction of the plastic. Eachdissolution column 31 thus has an inverse thermal gradient.Blowers FIG. 4 ), and 60 (seeFIG. 7 ) circulate the hot air through eachdissolution column 31. Aflue 59 connects to the first and secondhot air producers flue 59 includesbranch pipes outlet 59 c, and is inverted U shaped (seeFIG. 4 ). - The
decomposition section 32 includes the firststage decomposition column 47 controlled to 350-420° C. and the secondstage decomposition column 48 adjacent to the firststage decomposition column 47 and controlled to 450-580° C. (seeFIG. 7 ). Thedecomposition columns fourth dissolution column 31 d has an end that connects into the firststage decomposition column 47. This connection forms the storage section for the dissolved plastic. - The first
stage decomposition column 47 includes twounit decomposition columns partition 256 into two rows of left and right (seeFIG. 9 ). Theunit decomposition columns inner column 255, a plurality ofheatsink fins 253 around theinner column 255, alead screw 150, and aheat space 254 into which a hot air is sent. Eachlead screw 150 includes arotation shaft 251 and aspiral blade 252.Motors FIG. 5 ). - The second
stage decomposition column 48 has almost the same structure as the firststage decomposition column 47. The secondstage decomposition column 48 hasunit decomposition columns FIG. 6 ) which each have aninner column 148. Theinner column 148 contains alead screw 149.Motors 53, 54 (seeFIGS. 5 and 7 ) rotate the lead screws 149 slowly (4-5 revolutions per minute). - The
inner column 255 in the firststage decomposition column 47 has at its upper end asuperheat 151 for heating to 580-620° C. the decomposed gas flowing through the superheat 151 (seeFIG. 7 ). The decomposed gas that has been secondarily decomposed in the firststage decomposition column 47 exits through thesuperheat 151 andpipe 49, and is sent to the condenser 37 (seeFIG. 5 ) via ascrubber 60 for alkali cleaning. Thecondenser 37 then cools the decomposed gas into oil, which is stored through apipe 46 in anoil storage tank 42. Some of the oil stored in theoil storage tank 42 is supplied to thehot air producers - On the way of the
pipe 49 avalve 49 a resides for controlling the flow rate of the decomposed gas through thepipe 49. Thecondenser 37 needs to receive only the light decomposed gas that has been completely secondarily decomposed in the firststage decomposition column 47. The decomposed gas derived from thepipe 49, however, may contain incompletely secondarily decomposed gas that is slightly heavy. For a smaller amount of the decomposed gas derived from thepipe 49, the incompletely decomposed gas cannot go up the rising portion of thepipe 49 and will be returned into the firststage decomposition column 47 and sent into the secondstage decomposition column 48 via the fallingcolumn 120. For a larger amount of the decomposed gas derived from thepipe 49, the decomposed gas will be derived more strongly so that the incompletely decomposed gas can go up the rising portion of thepipe 49 and will be sent to thecondenser 37. Thevalve 49 a can thus adjust the amount of the decomposed gas derived from thepipe 49 to prevent the incompletely decomposed gas from being sent to thecondenser 37. - The first
stage decomposition column 47 is controlled to 350-420° C. as described above. The firststage decomposition column 47 is thus able to primarily and secondarily decompose the oil component corresponding to gasoline with a low decomposition temperature, and some of the oil component corresponding to coal oil and diesel oil. Thesuperheat 151 can completely secondarily decompose the insufficiently decomposed gases. Thecondenser 37 can cool into oil the decomposed gases that have been secondarily decomposed as described above. Thepipe 46 with a pump P can suck the gases that have been insufficiently converted into oil by thecondenser 37 and store them in theoil storage tank 42 as an off gas. - The expanded plastic component that has been incompletely secondarily decomposed in the first
stage decomposition column 47 is supplied to the bottom of the secondstage decomposition column 48 via the fallingcolumn 120. Thelead screw 149 in the secondstage decomposition column 48 will then send up the expanded plastic component at an angle. The secondstage decomposition column 48 is controlled to a temperature of 450-580° C. Thesecond decomposition column 48 can thus completely secondarily decompose the residual portion of the component corresponding to coal oil and diesel oil, and the crude oil component. The residuals such as metal and dirt that have been dropped together with the plastic will be stored in asludge tank 40 via asludge pipe 40 a. - As shown in
FIG. 18 , thesludge tank 40 containswater 40 b. Ametal gauge 40 c resides in thewater 40 b, which collects the residuals. Taking themetal gauge 40 c out of thesludge tank 40 can remove the residuals from thesludge tank 40. Acover 40 d with apartial opening 40 e covers the top surface of thesludge tank 40.Inactive gas 40 f that is heavier than the air, such as carbon dioxide gas, fills the space above thewater 40 b in thesludge tank 40. Thesludge pipe 40 a has its bottom in theinactive gas 40 f. Agas cylinder 40 g connects to thesludge tank 40. Thegas cylinder 40 g can supply into thesludge tank 40 theinactive gas 40 f, some of which overflows theopening 40 e. Theinactive gas 40 f in which thesludge pipe 40 a has its bottom can effectively prevent the air from flowing into the secondstage decomposition column 48 from thesludge pipe 40 a, thereby eliminating any danger of explosion. Thewater 40 b in which thesludge pipe 40 a has its bottom would float by the buoyancy the light residuals that may block the bottom of thesludge pipe 40 a. Theinactive gas 40 f in which thesludge pipe 40 a has its bottom can prevent the above described problem and allow for the smooth falling of the residuals into thewater 40 b. - The second
hot air producer 36 supplies a hot air viapipes FIG. 5 ) to the upper parts of the first and secondstage decomposition columns blowers decomposition columns decomposition columns hot air producer 35 supplies to thedissolution section 31 a hot air that is circulated, for example, by theblower 60 through thefourth dissolution column 31 d (seeFIG. 7 ). - The
inner column 148 of the secondstage decomposition column 48 has at its upper end apipe 50 that connects to acondenser 38 via ascrubber 61 for alkali cleaning (seeFIG. 5 ). The decomposed gas that has been decomposed in the secondstage decomposition column 48 goes through thepipe 50 to thescrubber 61 and into thecondenser 38. Thecondenser 38 then cools the decomposed gas into oil, which goes through apipe 86 to anoil storage tank 43. Some of this oil goes through a service tank ST2 to the above described first and secondhot air producers condensers 37, 38 (seeFIG. 3 ). - The first and second
stage decomposition columns pipes pipe 100. The exhaust from the first and secondstage decomposition columns pipes pipe 100 into the outside. The pump P collects through thepipe 86 into the oil storage tank 43 a gas that has not been converted into oil in thecondenser 38 which connects to the above described secondstage decomposition column 48. - Part of the foregoing
dissolution column 31 anddecomposition columns extendable column 700. Theextendable column 700 includes abellows portion 701 and a sliding portion 702 (seeFIG. 19 ). Thebellows portion 701 includes abellows 703 and a bellowsinner column 704 located in thebellows 703. The bellowsinner column 704 has a longer full length than thebellows 703. Thebellows 703 and bellowsinner column 704 are arranged with their ends aligned on one side. The bellowsinner column 704 extends beyond the other end of thebellows 703. Asupport column 705 resides around the extended bellowsinner column 704. These bellowsinner column 704 andsupport column 705 provide a slidingportion 702. Thesupport column 705 has an inner diameter that is slightly larger than the outer diameter of the bellowsinner column 704. The inner surface of thesupport column 705 and the outer surface of the bellowsinner column 704 provide sliding surfaces. InFIG. 19 , aninner column 706 with the same diameter as the bellowsinner column 704 resides on the portion of thesupport 705 on which the bellows inner 704 does not reside. Formed on the butt side ends between the bellowsinner column 704 and theinner column 706 are correspondingshoulders shoulders - The
extendable column 700 provided in a part of thedissolution column 31 anddecomposition columns dissolution column 31 anddecomposition columns first dissolution column 31 a that is heated from room temperature to about 200° C. and has a longer full length due to expansion, theextendable column 700 provided in a part of thefirst dissolution column 31 a can reduce thebellows 703 to reduce the bellowsinner column 704 toward the slidingportion 702 to absorb the expansion of thefirst dissolution column 31 a. - In the
extendable column 700 shown inFIG. 19 , the slidingportion 702 includes the bellowsinner column 704 with its sliding area outside thebellows 701, and thesupport column 705 with the diameter larger than the bellowsinner column 704. The bellowsinner column 704 can therefore have a greater thickness without reducing the inner diameter of the bellowsinner column 704. This can prevent the deformation of theextendable column 700, therefore the damage of thebellows 703 due to the deformedextendable column 700, and the fire due to the decomposed gases or the like flowing out of the damaged portion of thebellows 703. - The
dechlorination treatment system 33 will now be described in detail. -
Pipes dissolution columns dissolution section 31 connect to a pipe 78 (seeFIG. 5 ). Thepipe 78 in turn connects to the first separator 37 (seeFIG. 10 ). Thefirst separator 37 can separate the hydrogen chloride gas generated in thedissolution sections separator 37 includes acooling coil 301 on the top. The hydrogen chloride gas flowing through thepipe 78 will be cooled through the coolingcoil 301 and released in the lower part of thefirst separator 37 below the coolingcoil 301. After being released, the hydrogen chloride gas goes through the coolingcoil 301, the upper part of thefirst separator 37, and apipe 79 into thesecond separator 38 that has the same structure as thefirst separator 37. After being separated in thesecond separator 38, the hydrogen chloride gas goes into thethird separator 39 that has the same structure as the first andsecond separators third separator 39, the hydrogen chloride gas goes through apipe 81 to the lower part of thereactor 300. A plurality of theseseparators - The
reactor 300 includes a stirringbar 306 withblades 308. Ahydrated lime tank 83 connects to the upper part of thereactor 300. Aheating column 305 resides around thehydrated lime tank 83 to dry the hydrated lime in thehydrated lime tank 83. Alead screw 303 resides at the lower part of thehydrated lime tank 83. Amotor 304 rotates thislead screw 303. - A
lead screw 309 resides at the bottom of thereactor 303. Amotor 310 rotates thislead screw 309. Aheating column 313 heats the surrounding area of thelead screw 309 to dry and remove the water generated during the reaction in the reactor. Acalcium chloride tank 312 contains the calcium chloride generated during the reaction in thereactor 309. Temperature sensors S1, S2, and S3 reside at appropriate positions in the height direction of thereactor 300. The temperature sensors S1, S2, and S3 detect the reaction heat. These reactor heat detection signals can control the rotation of themotor 304 for thehydrated lime tank 83 and themotor 310 for thelead screw 309 for evacuating thereactor 300. Specifically, the stirringbar 306 in thereactor 300 consistently rotates, and a large amount of hydrogen chloride gas flowing into thereactor 300 can facilitate the reaction to generate a large amount of heat. The temperature sensor S3 at the highest position that detects reaction heat equal to or greater than a predetermined value will cause thelead screw 303 for thehydrated lime tank 83 to rotate to send a large amount of the hydrated lime into thereactor 300. Then the reaction proceeds to generate less reaction heat and slightly reduce the temperature. When the temperature sensor S2 at an intermediate position detects a temperature in a predetermined range, the hydrated lime is accordingly supplied. Then the reaction further proceeds to slow down. When the temperature sensor S1 at the lowest position detects a predetermined temperature, it determines that the reaction stops and rotates thelead screw 309 for evacuating thereactor 300 and collects the calcium chloride generated into thecalcium chloride tank 312. After the calcium chloride generated being collected, when the reaction starts again, the temperature sensor S1 detects the starting of the reaction and causes thelead screw 303 to rotate to send the hydrated lime from thehydrated lime tank 83 into thereactor 300. As the temperature sensors S2, S3 detect the reaction heat in sequence, more hydrated lime will be supplied. As the reaction heat decreases, less hydrated lime will be supplied, and the above described procedure will be repeated. - It is said that the hydrogen chloride gas usually needs a solvent to react with a dry neutralizing agent. Here, the water generated in the reaction of the hydrogen chloride gas with the hydrated lime can provide the solvent which can facilitate the neutralization reaction. The reaction formula is as follows:
2HCl+Ca(OH)2=CaCl2+2H2O - A
vacuum pump 314 resides to evacuate water that is generated as vapor in this reaction and draw the hydrogen chloride gas into thereactor 300. To provide a constant suction load in thevacuum pump 314, arelief valve 315 for air inflow resides on the inlet side of thevacuum pump 314. Ascrubber 317 for alkali cleaning resides to remove the hydrogen chloride gas that has been insufficiently reacted in thereactor 300. - The off
gas treatment system 34 will now be described. -
FIG. 11 shows a schematic diagram of the offgas treatment system 34. As shown inFIG. 11 , the offgas treatment system 34 includes acasing 236. In the operation of the plant for conversion into oil, aburner 234 is consistently connected to thecasing 236, which is heated to about 1200° C. - The above-described
casing 236 contains a plurality ofceramic prisms inlet 235 connected to the above describedoil storage tanks outlet 237 into the first and secondhot air producers - The off gas is an endocrine disrupter, such as acetaldehyde, which has not been converted into oil in the
condensers oil storage tanks gas treatment system 34. Thecondensers gas treatment system 34. - The safety system in the tilted columns and the deodorant system will now be described.
- As shown in
FIG. 20 , a number of temperature sensors S, S, . . . S reside on each dissolution column in thedissolution section 31 and each tilted column in thedecomposition section 32. Each sensor S connects to acontroller 511. Thiscontroller 511 can control the open/close of avalve 513 connected to a carbondioxide gas cylinder 512. This carbondioxide gas cylinder 512 connects to a hot air circulation path P through which the first and secondhot air producers dissolution section 31 anddecomposition section 32. Thecontroller 511 opens thevalve 513 to supply the carbon dioxide gas through the hot air circulation path Q into thedissolution section 31 anddecomposition section 32, if the temperature sensor S detects an abnormal temperature due to such as accidents. This can cool thedissolution section 31 anddecomposition section 32, and stop the operation of the plant for conversion intooil 30. - An accumulation facility A for the plastic to be treated has at the top a
suction unit 514 with asuction fan 514 a. Thesuction unit 514 particularly sucks an air with an odor caused by the plastic waste and sends it to thehot air producer 36 for the deodorization by combustion. - Plastic chips P crushed by a
crusher 515 are dried in a drier 516 with the hot air from thehot air producer 36. The dried plastic chips P are then sent to thehopper 41. The drier 516 in which the hot air dries the plastic chips P may be filled with an odor. The air with an odor in the drier 516 is sent to thehot air producer 35 for treatment after acyclone 517 removes fine particles mixed in the air. These systems can provide excellent deodorization. - The off
gas treatment section 34 for the off gas treatment may decompose the air with an odor. Thehot air producer gas treatment section 34, therefore, may treat the air with an odor. - The embodiments described above use two stages of the decomposition columns. The
dissolution section 200 may be provided as follows: the secondstage decomposition column 48 may precede the thirdstage decomposition column 210 that has the same structure and the same tilting angle as the secondstage decomposition column 48, as shown inFIG. 12 . The temperature range may be of 350-400° C. in the first stage decomposition column, 400-480° C. in the second stage decomposition column, and 480-580° C. in the third stage decomposition column. Such three stages of the decomposition columns can provide a more moderate distribution of the decomposition temperature and a longer decomposition time, thereby making it possible to adapt to any change in the decomposition condition such as the plastic specific gravity, and to ensure the reliable secondary decomposition. - Specifically, the upper end of the second
stage decomposition column 48 connects, via a fallingcolumn 218, to the bottom of the thirdstage decomposition column 210 tilted at the same angle. The secondstage decomposition column 48 sends the undecomposed expanded plastic and decomposed gas that have not been extracted in thecolumn 48 into the thirdstage decomposition column 210 through the fallingcolumn 218. The thirdstage decomposition column 210 can secondarily decompose the undecomposed expanded plastic and decomposed gas. The secondarily decomposed gas goes through ascrubber 216 for alkali cleaning into acondenser 213 which cools the decomposed gas into oil corresponding to A crude oil. This oil goes through apipe 214 into theoil storage tank 215 where the oil is stored. Ablower 221 connects to the third stage decomposition column from the top to form an inverse thermal gradient. The residuals go through asludge pipe 219 into asludge tank 220 filled with water where the residuals are stored. A pump P sucks the decomposed gas that has not been converted into oil in the above describedcondenser 213 of the thirdstage decomposition column 210. The pump P then sends the decomposed gas through thepipe 214 into theoil storage tank 215 where the gas is stored. The first and secondstage decomposition columns superheat - The embodiment shown in
FIG. 312 uses adissolution section 200 that is formed vertically (perpendicularly). Specifically, the first, second, andthird dissolution columns connections hopper 41 goes right through thefirst dissolution column 201, left through thesecond dissolution column 202, and right through thethird dissolution column 203 before being supplied to the bottom of the firststage decomposition column 47. Amotor 208 rotates alead screw 207 of thethird dissolution column 203 at the lowest stage. The rotation of themotor 208 also rotates alead screw 206 of thefirst dissolution column 201 via achain 209. The rotation of thelead screw 206 in turn rotates alead screw 212 of thesecond dissolution column 202 via gears G1, G2 Ablower 213 circulates a hot air up through thedissolution section 200 by drawing the air out of the top at a lower temperature to the bottom at a higher temperature via apipe 222. - In the embodiment shown in
FIG. 21 , a heatingmedium heating system 600 supplies a heating medium which heats the first tofourth dissolution columns medium heating system 600 heats the heating medium to a predetermined temperature and sends the medium through aheating medium pipe 601 into aheating medium space 135′ of thedissolution column 31. Theheating medium space 135 intervenes between aninner wall 131 and anouter case 136, as for the above describedhot air space 135. Acirculation pump 602 circulates the heating medium through theheating medium space 135 from downstream to upstream. Thefirst dissolution column 31 a is controlled to 190-200° C., thesecond dissolution column 31 b to 210-230° C., thethird dissolution column 31 c to 230-260° C., and thefourth dissolution column 31 d to 300-340° C., as in the above described hot air heating. - The heating medium thus used instead of the hot air can a) greatly improve the heat transfer efficiency, b) reduce the temperature drop in the
dissolution column 31 when the plant stopped, because the heating medium cools less rapidly than the hot air, thereby allowing the plant to start up more quickly, and c) prevent the fire even if theinner column 131 of thedissolution column 31 is damaged. - The heating medium is used only for heating the
dissolution column 31 because the heating medium generally operates at 350 #1# or less. Any other suitable heating medium, however, can be selected also to heat thedecomposition columns dissolution columns 31 that are controlled to lower temperatures (such as first, second, andthird dissolution columns - In the embodiment shown in
FIG. 13 , aconnection 500 connects thefourth dissolution column 31 d and the lower part of the firststage decomposition column 47. Through theconnection 500, thecolumn 31 d supplies the dissolved expanded plastic into the bottom of theinner column 255 in the firststage decomposition column 47. The above describedconnection 500 may receive vegetable or animal cooking oil or their waste oil or the like stored in atank 502. Each dissolution column primarily and secondarily decomposes the mixture of the oil and expanded plastic. This can collect reformed oil through chemical decomposition reaction. - Generally, as shown in
FIGS. 1-4 , plastics such as polyethylene, polypropylene, polystyrene, ABS resin, and acrylic resin are thermally decomposed into oil (90%) that is collected as the generated oil, an off gas (7-8%) that is treated in the offgas treatment system 34, and carbide (2-3%) that is collected as the residual into theresidual tank 40. Polyvinyl chloride is neutralized by calcium hydroxide into calcium chloride (about 58%), and the residual (about 42%) is thermally decomposed, but only about 30% is converted into oil and collected. - The disclosure of Japanese-patent application No. 2002-017650 (filed on Jan. 25, 2002) including the specification, claims, drawings, and abstract, and Japanese patent application No. 2002-301895 (filed on Oct. 16, 2002) including the specification, claims, drawings, and abstract are incorporated herein by reference in their entirety.
- This invention is not limited to the embodiments described above. The above-described embodiments are illustrative, and any technical idea that has the substantially identical configuration and operation as the technical idea set forth in the claims of the present invention is included in the technical scope of the present invention.
- Industrial Applicability
- As describe above, the method and plant for converting plastic into oil according to the present invention are useful as the method and plant for converting plastic into oil for collecting the oil from the plastic waste.
Claims (31)
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2002017650A JP2003213276A (en) | 2002-01-25 | 2002-01-25 | Method and plant for converting plastic into oil |
JP2002-17650 | 2002-01-25 | ||
JP2002-301895 | 2002-10-16 | ||
JP2002301895A JP2004137335A (en) | 2002-10-16 | 2002-10-16 | Oiling installation |
PCT/JP2003/000413 WO2003064561A1 (en) | 2002-01-25 | 2003-01-20 | Method and plant for converting plastic into oil |
Publications (1)
Publication Number | Publication Date |
---|---|
US20050075521A1 true US20050075521A1 (en) | 2005-04-07 |
Family
ID=27667424
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/502,624 Abandoned US20050075521A1 (en) | 2002-01-25 | 2003-01-20 | Method and plant for converting plastic into oil |
Country Status (4)
Country | Link |
---|---|
US (1) | US20050075521A1 (en) |
KR (1) | KR20040048368A (en) |
TW (1) | TW200302867A (en) |
WO (1) | WO2003064561A1 (en) |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090050525A1 (en) * | 2005-03-02 | 2009-02-26 | Manfred Sappok | Method for deploymerising residues containing hydrocarbons and device for carrying out said method |
US20090117015A1 (en) * | 2006-05-25 | 2009-05-07 | Yoshiko Shimo | Liquefying apparatus |
EP1841842A4 (en) * | 2005-01-26 | 2009-07-01 | Gen Atomics | Method and system for fueling a power/heat generating unit with plastic material |
US20090321317A1 (en) * | 2006-08-25 | 2009-12-31 | Granit System S.A. | Method and device for processing plastic-containing waste |
US20100221158A1 (en) * | 2007-10-19 | 2010-09-02 | Kusatsu Electric Co., Ltd. | Catalyst Circulating Waste Plastic/Organic Matter Decomposition Apparatus And Decomposition System |
WO2012016633A2 (en) | 2010-07-26 | 2012-02-09 | Wieser-Linhart Emil A J | System and method for producing fuels from biomass/plastic mixtures |
EP2553005A1 (en) * | 2010-03-31 | 2013-02-06 | Agilyx Corporation | Systems and methods for recycling plastic |
US8680349B2 (en) | 2009-03-14 | 2014-03-25 | Clariter Ip S.A. | Apparatus for conducting thermolysis of plastic waste in a continuous manner |
US20140246301A1 (en) * | 2011-10-19 | 2014-09-04 | Blest Co., Ltd. | Liquefying apparatus |
US9145520B2 (en) | 2006-08-24 | 2015-09-29 | Agilyx Corporation | Systems, and methods for recycling plastic |
US9162944B2 (en) | 2013-04-06 | 2015-10-20 | Agilyx Corporation | Systems and methods for conditioning synthetic crude oil |
US20180187085A1 (en) * | 2015-07-07 | 2018-07-05 | Konstantin Vladimirovich Ladygin | Pyrolysis method and plant for processing organic material by pyrolysis |
US10717936B2 (en) | 2016-08-01 | 2020-07-21 | Sabic Global Technologies B.V. | Catalytic process of simultaneous pyrolysis of mixed plastics and dechlorination of the pyrolysis oil |
US11407947B2 (en) | 2020-12-10 | 2022-08-09 | Agilyx Corporation | Systems and methods for recycling waste plastics |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
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KR100956658B1 (en) * | 2008-03-25 | 2010-05-10 | (주)피이알이엔티 | Fitness type pyrolysis oil recovery apparatus using waste material |
KR102345829B1 (en) * | 2020-05-04 | 2022-01-03 | 김학권 | A Recycling Device And Method Thereof |
CN115072670B (en) * | 2022-05-19 | 2023-06-13 | 西南石油大学 | Reaction device for preparing elemental sulfur and hydrogen by decomposing hydrogen sulfide with molten salt |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4851601A (en) * | 1988-01-19 | 1989-07-25 | Mobil Oil Corporation | Processing for producing hydrocarbon oils from plastic waste |
US5364995A (en) * | 1991-03-05 | 1994-11-15 | Bp Chemicals Limited | Polymer cracking |
US5608136A (en) * | 1991-12-20 | 1997-03-04 | Kabushiki Kaisha Toshiba | Method and apparatus for pyrolytically decomposing waste plastic |
US5756871A (en) * | 1995-05-23 | 1998-05-26 | California Engineering Consultants Co., Ltd. | Treating method for converting wastes into resources and its equipment |
US6126907A (en) * | 1998-06-17 | 2000-10-03 | Wada; Youichi | Thermal decomposition apparatus of reversed temperature gradient type for polymer waste |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3575914B2 (en) * | 1996-04-26 | 2004-10-13 | 株式会社東芝 | Plastic processing method and apparatus |
JPH11116726A (en) * | 1997-10-21 | 1999-04-27 | Nkk Plant Engineering Corp | Method of processing of waste polyvinyl chloride |
-
2003
- 2003-01-20 WO PCT/JP2003/000413 patent/WO2003064561A1/en active Application Filing
- 2003-01-20 US US10/502,624 patent/US20050075521A1/en not_active Abandoned
- 2003-01-20 KR KR10-2003-7001944A patent/KR20040048368A/en not_active Application Discontinuation
- 2003-01-24 TW TW092101606A patent/TW200302867A/en unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4851601A (en) * | 1988-01-19 | 1989-07-25 | Mobil Oil Corporation | Processing for producing hydrocarbon oils from plastic waste |
US5364995A (en) * | 1991-03-05 | 1994-11-15 | Bp Chemicals Limited | Polymer cracking |
US5608136A (en) * | 1991-12-20 | 1997-03-04 | Kabushiki Kaisha Toshiba | Method and apparatus for pyrolytically decomposing waste plastic |
US5756871A (en) * | 1995-05-23 | 1998-05-26 | California Engineering Consultants Co., Ltd. | Treating method for converting wastes into resources and its equipment |
US6126907A (en) * | 1998-06-17 | 2000-10-03 | Wada; Youichi | Thermal decomposition apparatus of reversed temperature gradient type for polymer waste |
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EP1841842A4 (en) * | 2005-01-26 | 2009-07-01 | Gen Atomics | Method and system for fueling a power/heat generating unit with plastic material |
US20090050525A1 (en) * | 2005-03-02 | 2009-02-26 | Manfred Sappok | Method for deploymerising residues containing hydrocarbons and device for carrying out said method |
CN101495600B (en) * | 2006-05-25 | 2013-03-27 | 布莱斯特股份有限公司 | Liquefying apparatus |
US20090117015A1 (en) * | 2006-05-25 | 2009-05-07 | Yoshiko Shimo | Liquefying apparatus |
CN101495600A (en) * | 2006-05-25 | 2009-07-29 | 布莱斯特股份有限公司 | Liquefying apparatus |
US8187428B2 (en) | 2006-05-25 | 2012-05-29 | Blest Co., Ltd. | Liquefying apparatus |
US9145520B2 (en) | 2006-08-24 | 2015-09-29 | Agilyx Corporation | Systems, and methods for recycling plastic |
US20090321317A1 (en) * | 2006-08-25 | 2009-12-31 | Granit System S.A. | Method and device for processing plastic-containing waste |
US20100221158A1 (en) * | 2007-10-19 | 2010-09-02 | Kusatsu Electric Co., Ltd. | Catalyst Circulating Waste Plastic/Organic Matter Decomposition Apparatus And Decomposition System |
US8241584B2 (en) * | 2007-10-19 | 2012-08-14 | Kusatsu Electric Co., Ltd. | Catalyst circulating waste plastic/organic matter decomposition apparatus and decomposition system |
US9376632B2 (en) | 2009-03-14 | 2016-06-28 | Clariter Ip S.A. | Apparatus for conducting thermolysis of plastic waste and method of thermolysis in continuous manner |
US8680349B2 (en) | 2009-03-14 | 2014-03-25 | Clariter Ip S.A. | Apparatus for conducting thermolysis of plastic waste in a continuous manner |
EP2553005A1 (en) * | 2010-03-31 | 2013-02-06 | Agilyx Corporation | Systems and methods for recycling plastic |
EP2553005A4 (en) * | 2010-03-31 | 2013-12-25 | Agilyx Corp | Systems and methods for recycling plastic |
WO2012016633A2 (en) | 2010-07-26 | 2012-02-09 | Wieser-Linhart Emil A J | System and method for producing fuels from biomass/plastic mixtures |
WO2012016633A3 (en) * | 2010-07-26 | 2012-12-06 | Wieser-Linhart Emil A J | System and method for producing fuels from biomass/plastic mixtures |
US20140246301A1 (en) * | 2011-10-19 | 2014-09-04 | Blest Co., Ltd. | Liquefying apparatus |
US9162944B2 (en) | 2013-04-06 | 2015-10-20 | Agilyx Corporation | Systems and methods for conditioning synthetic crude oil |
US9493713B2 (en) | 2013-04-06 | 2016-11-15 | Agilyx Corporation | Systems and methods for conditioning synthetic crude oil |
US20180187085A1 (en) * | 2015-07-07 | 2018-07-05 | Konstantin Vladimirovich Ladygin | Pyrolysis method and plant for processing organic material by pyrolysis |
US10717936B2 (en) | 2016-08-01 | 2020-07-21 | Sabic Global Technologies B.V. | Catalytic process of simultaneous pyrolysis of mixed plastics and dechlorination of the pyrolysis oil |
US11407947B2 (en) | 2020-12-10 | 2022-08-09 | Agilyx Corporation | Systems and methods for recycling waste plastics |
Also Published As
Publication number | Publication date |
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TW200302867A (en) | 2003-08-16 |
WO2003064561A1 (en) | 2003-08-07 |
KR20040048368A (en) | 2004-06-09 |
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