JPS6232131A - Apparatus for reclaiming waste plastic - Google Patents

Abstract

PURPOSE:To thermally crack a large quantity of a waste plastic material continuously in good efficiency into a cracked oil, by using a construction in which a vertical cupola melting furnace is provided on the upstream side of a thermal cracking furnace and waste plastic is fed to this furnace after being molten in the melting furnace. CONSTITUTION:A waste plastic material is crushed with a crusher 1 and fed through feed tank 3, 5, etc., to the top of a vertical cupola melting furnace 6 and molten by heating with hot air supplied from a hot air generator 7. The molten plastic material in a state heated through a double pipe heater equipped with a heating means 9 is transferred to a thermal cracking furnace 10 and thermally cracked with agitation by means of an impeller 13. The formed dry- distilled gas is withdrawn from an exit 16 and condensed by cooling in a condenser 17 to obtain a cracked oil. Thic cracked oil is led through a filter oil refiner 22 to a refined oil tank 23 and distilled into a heavy fraction and a light fraction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waste plastic recycling processing device, and can be described as a method for thermally decomposing waste plastics included in general waste and industrial waste in an inert atmosphere. The present invention relates to a waste plastic recycling processing device for cooling and condensing the decomposed and transmolten gas and using the liquefied combustible decomposed oil as recycled energy.

In general, when organic substances are placed in a closed cylindrical container, i.e., a pyrolysis furnace, in a manner that prevents the entrainment of air, and then heated in an inert atmosphere, they become melted or steamed, resulting in changes in molecular structure and formation of carbides (char). However, if the heating degree at that time is approximately 800°C or higher, it becomes a flammable gas, and at 500°C it decomposes into gas.
It is well known that if it is less than that, it will be recovered as oil.

Various attempts have been made to thermally decompose waste plastics and reduce them to fuel oil, but the problem is that continuous large-scale processing of waste plastics is not possible, and the quality of the decomposed oil is poor and lacks safety as an alternative oil. In general, there were various technical and economical problems, such as a large number of components and problems with the operability of the entire plant equipment.

The main object of the present invention is to make the thermal decomposition of plastics more effective by disposing a melting furnace for completely dehydrating and drying the material and melting it into a molten state, upstream of the thermal decomposition furnace.

Furthermore, in order to achieve the above-mentioned purpose, a means for stirring the melt or the decomposed material (to promote decomposition with uniform stirring) is provided in the lower part of the melting furnace and the pyrolysis furnace, and a means for removing the unburnt material is provided. It consists in being equipped with the means, etc.

Another object of the present invention is to completely deodorize the exhaust gases generated in the melting furnace by burning them in the thermal decomposition furnace at a temperature of 700°C or higher, and also to completely deodorize the exhaust gases generated in all other parts. By having a structure in which combustion is performed for the purpose of deodorization in the furnace, secondary and tertiary pollution caused by the dissipation of exhaust gas and generated gas is prevented.

In other words, the feature of this invention is to completely digest this type of waste plastic pyrolysis method, which had a big technical and economical barrier, and to create the most economically efficient recycling system. A melting furnace is installed in the front stage of the pyrolysis furnace, and in order to continuously operate the melting furnace and the pyrolysis furnace with high efficiency, a means for stirring the material to be treated and taking out the residue is provided in the furnace, and furthermore, a means for stirring the material to be treated and removing the residue is provided, and further The plant is completely reused, and a means of thermal decomposition of the exhaust gas is installed to deodorize and purify it, making it a pollution-free treatment plant.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be explained in detail below based on drawings illustrating embodiments.

In the drawing, 1 is a crusher for the plastic to be processed (in the case of the plastic to be processed, it may be stored directly in a hopper depending on the shape and particle size), 2 is a suction turbo blower for pumping the crushed plastic, and 3 is a crusher for the plastic to be processed. is a raw material storage quantitative supply tank, 4
5 is an injection feeder, 5 is a molten raw material quantitative supply tank, and the lower stage is equipped with an injection feeder color a for feeding.

6 is a melting furnace, and a plurality of heating means 7a, 7b from a hot air generator (burner) 7 are arranged on the side. 8 is a melt transfer pump installed at the lower part of the melting furnace B, and the discharge port 8
Everything from a to the pipe 9a is surrounded by heating means 9. Reference numeral 10 denotes a pyrolysis tank having a closed structure, which is housed in a hot air swirl type heating furnace 11, and has an end of the heated piping 9a fixedly installed at the top, and a residue discharge port 12 and a main shaft at the bottom. It is equipped with stirring blades 13 that can rotate in reverse. 14 is a hot air generator serving as a heating means for the hot air swirl heating furnace 11, which maintains the temperature inside the furnace at 800°C;
Exhaust gas generated from inside the furnace is introduced into the hot air generator 14 via a hot air circulation injector 15 through piping. 16
is a cracked gas exhaust port located at the top of the pyrolysis tank 10,
It is connected to a cracked gas condenser 17. Reference numeral 18 denotes a cracked crude oil receiving tank that has been cooled and condensed by the condenser 17, from which the cracked crude oil is transferred via a switching valve 19 to a cracked crude oil storage tank 20 and a relay tank 21, and then to a filter oil purification device 22. That is, when the filtration oil purification device 22 is abnormal, the crude oil is transferred to and stored in the cracked crude oil storage tank 20 by switching the switching valve 19. 23 is a double crude oil cracking tank for further refining and fractionating the cracked crude oil that has been filtered and purified in the previous stage, and is heated by a hot air heating furnace 24.
It is stored inside.

25 is a hot air generator attached to the hot air heating furnace, 26 is a fractionated gas outlet protruding from the upper part of the subtank 23b of the crude oil cracking tank, 27 is a condenser for refining light oil, and 28 is a subtank. It is a heavy oil cooling tank that is connected to the tank 2-3b, which flows out from the lower part of the tank, and is piped from the suspicious oil refining condenser 27, through the relay tank 29, through the light oil filtration and oil purification device 30, and to the recovered oil underground tank 31. It is connected. Further, the heavy oil cooling tank 28 is connected to a fuel storage tank 34 through a relay tank 32 and a heavy oil filtering and purifying device 33 . Further, 35 is a hot air circulation injector installed on the top of the hot air heating furnace 24 that accommodates the crude oil cracking tank 23, and the gas generated in the furnace is transferred to the hot air generator 25.
The final exhaust gas is discharged from the ejector 36. Further, the exhaust gas generated from the two condensers 17 and 27 is introduced into the hot air swirl heating furnace 11 surrounding the thermal decomposition tank 10 via the blower 37, and is combusted.

In the present invention having the above configuration, in order to perform thermal decomposition in the thermal decomposition tank 10 more effectively and efficiently, a melting furnace 6 is provided at the front stage of the thermal decomposition tank 10. It is a cubicle-type vertical furnace with a processing material inlet at the top and multiple hot air inlets in the middle. Therefore, the structure is such that the moisture contained in the object to be treated is evaporated in the upper part, and then gradually moves downward to raise the temperature and dissolve it. An unburnt material outlet 6a is provided at the lower end and is normally closed by a plate valve 6b. Second
As shown in the figure, a hot air passage 6C surrounds the melting furnace 6 in communication with the opening of the hot air generator 7, and a hot air lower a branches off from the passage.

7b... is connected to the furnace wall in an open state, inside the furnace.

The direction is such that the hot air swirls.

Next, a heating means 9, that is, a pyrolysis tank 10il-t guided by a double heating tube, has a stirring blade 13 at the bottom, and a valve 13a'z that moves up and down coaxially with the rotation axis of the stirring blade. A residue discharge port 12 is provided. This stirring blade 13
is provided to promote the decomposition of undecomposed materials, but it also has the effect of moving undecomposed materials upwards and causing convection.

Furthermore, in this invention, all exhaust gases generated from each furnace, that is, the melting furnace 6, the hot air swirl heating furnace 11 housing the pyrolysis tank 10, and the hot air heating furnace 24 housing the crude oil refining tank 26, are converted into the highest temperature hot air. It is burned in the rotating heating furnace 11 for the purpose of deodorizing, and only the final exhaust gas is sent to the ejector 36.
It is a completely pollution-free device as it uses a method of emitting water from the air.

Incidentally, the cracked oil filtration oil purification device 22 used in the embodiment of this invention
As for the light oil filtration oil purification device 30 and the heavy oil filtration oil purification device 33, it is possible to use well-known devices. Each hot air generator installed 7.14, 25
According to the invention, for example, polystyrene, polyethylene,
If a single thermoplastic material such as polypropylene is used as waste plastic, 75-90% by weight of recycled oil can be extracted, but this is a breakthrough in that it can be operated using 10-15% of the recovered oil as fuel. It has economic efficiency.

Next, based on the flow chart shown in FIG.
The functions and effects of the device of the present invention will be explained in further detail.

First, the material pulverized by the pulverizer 1 is stored in a raw material storage/quantitative supply tank 3 and is pressure-fed to the molten raw material quantitative supply tank 5 for a fixed amount, from where it is blown into the upper part of the melting furnace 6 via the injection feeder 5a. be done.

Since hot air with an internal temperature of 450 to 600 DEG C. is swirling in the melting furnace, the moisture contained in the raw material is first evaporated in the upper part, and the temperature of the raw material itself to be processed increases, and the material is further melted.

The melted glass raw material is extruded through a heat-resistant melt transfer pump 8 into a double heating tube equipped with a heating means 9, and then fed into a pyrolysis tank 10 at about 800°C where it is thermally decomposed and vaporized. Ru. While promoting the decomposition of the materials to be decomposed by stirring blades 13 disposed at the lower part of the thermal decomposition tank 10, the vaporized cracked gas is cooled and condensed from the exhaust port 16 in the cracked gas condenser 17 to produce cracked crude oil.

The obtained cracked crude oil passes through a relay tank 21, a crude oil filtration and oil purification device 22, which filters and purifies the crude oil, and is further led to a two-unit crude oil refining tank 23. A hot air heating furnace 24 surrounding this tank
The crude oil in the tank is fractionated into heavy and light components at a temperature of approximately 650°C. The light components are discharged from the discharge port 26 and cooled in the light oil refining condenser 27 to become light oil.The light oil is sent to the light oil purification device 30 via the relay tank 29, and the purified light oil is transferred to the underground tank. It will be collected on 31st. On the other hand, heavy components are extracted from the bottom of the tank, cooled in a heavy oil cooling tank 28, passed through a relay tank 32, and then collected in a fuel storage tank 34 via a heavy oil filtration and oil purification device 33.

The fuel necessary for this device is drawn out from the fuel storage tank 34,
The remainder is collected into one of the separation chambers of the underground tank 31.

In order to increase decomposition efficiency, the temperature of the floor is kept in a molten state at 450 to 600°C, resulting in extremely good thermal decomposition.At the same time, stirring blades are installed at the bottom of the pyrolysis tank to promote uniform decomposition of the decomposed substances. , and even more stirring.

By installing an on-off valve that allows the outer cylindrical shaft of the shaft to slide up and down, and removing the residue by simply rotating the handle, it is possible to continuously decompose large amounts of waste plastic, etc. This has the effect of eliminating various conventional problems.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the present invention, and FIG. 1 is a flowchart of a plant in which the invention is implemented, and FIG. 2 is a partial sectional view of a melting furnace. In the drawing, 1. Crusher 2. Suction turbo blower 3. Raw material storage quantitative supply tank 4. Injection feeder 5. Molten raw material quantitative supply tank 6. Melting furnace 7.14.25. Hot air generator 8...Melt transfer pump 9...Heating means 10...Pyrolysis tank 11...Hot air swirl heating furnace 12...
Residue outlet 13... Stirring blade 16.26... Discharge port 17.27.
e Condenser 21.29, 32... Relay night, Nk 22.30.33 - @ Filter oil purification device 23... Crude oil refining tank 28... Heavy oil cooling tank 30... Light oil filter oil purification device 31・・Underground tank 33 ・・Heavy oil f purification device 34 --Fuel storage tank 36 ・・Ejector - Figure 2 Procedure correction writing method) % formula % 1. Display of incident Patent application No. 172218 of 1985 2. Name of invention Waste plastic recycling processing device 3
, Relationship with the case of the person making the amendment Patent applicant 5, Subject of the amendment Drawing 6, Contents of the amendment As shown in the attached sheet

Claims (4)

[Claims] (1) In a waste plastic recycling processing equipment that heats and decomposes waste plastic raw materials crushed into arbitrary sizes in a pyrolysis furnace to generate dry distilled gas, and cools and condenses the generated gas to form cracked oil, the upper A vertical cupola type melting furnace is provided with a material supply means connected to the top, a plurality of stages and a plurality of hot air inlets in the central body, and a melt transfer means equipped with a heating structure connected to the lower part. A waste plastic recycling processing apparatus characterized in that the molten material is transferred in a heated state to the pyrolysis furnace via the molten material transfer means. (2) In a waste plastic recycling processing device that heats and decomposes waste plastic crushed into arbitrary sizes in a pyrolysis furnace to generate dry distilled gas, and cools and condenses the generated gas to form cracked oil, the upper The central body has a plurality of stages and a plurality of hot air inlet ports, the lower part has a melt transfer means with a heating structure, and the bottom end has an unburnt material removal valve. A vertical cupola-type melting furnace is installed,
Means for heating and transferring the melt to a pyrolysis furnace heated to about 600 to 750°C via the melt transfer means, and cooling and condensing the cracked gas generated in the pyrolysis furnace to form cracked oil; After filtering and purifying the decomposed oil, the temperature is again about 500 to 600°C.
A waste plastic recycling processing device comprising a means for refining waste plastic in a refining tank and fractionating it into light oil and heavy oil. (3) A valve seat provided in the bottom opening of the pyrolysis tank, a stirring blade capable of forward and reverse rotation into which the opening is fitted, and a stirring blade fitted into the outer cylindrical shaft coaxial with the rotating shaft of the stirring blade, and the above-mentioned a bearing that rotatably holds the rotating shaft, a valve body provided at the tip of the outer cylinder shaft and engaged with the valve seat, a sliding mechanism that moves the outer cylinder shaft up and down, and a residue protruding from the bottom opening. Claims 1 to 2 have an on-off valve for removing residue, which is provided with a take-out port and can coaxially prevent rotation of the stirring blade and airtight leakage of the opening.
The waste plastic recycling processing equipment described in Section 1. (4) In a waste plastic recycling processing equipment that heats and decomposes waste plastic raw materials crushed into arbitrary sizes in a thermal furnace to generate dry distilled gas, and cools and condenses the generated gas to produce cracked oil, the upper A vertical cupola-type melting furnace is installed, which has a material supply means connected to the top, a plurality of hot air inlets at 450 to 500°C in multiple stages in the central body, and a melt transfer means connected to the lower part. The melt is transferred in a heated state to a pyrolysis furnace heated to about 600 to 750°C via the melt transfer means, and the cracked gas generated in the pyrolysis furnace is cooled, condensed, and decomposed. After filtering and purifying the decomposed oil, it is again put into a refining tank at about 500 to 600°C to produce light oil,
It includes a means for fractionating heavy oil and sucks odor-bearing gas generated in the melting furnace, non-condensable combustible gas in the condenser, and combustion in the pyrolysis furnace. A waste plastic recycling processing device characterized in that it is introduced into a high-temperature area to perform combustion thermal decomposition.