JPH1143676A - Facility for reducing waste plastic to oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simplified and small-sized compact facility to realize cost reduction and easy maintenance. SOLUTION: A facitily for reducing waste plastics to oil 1 comprises a vessel body 3 with its narrow bottom side 3d by inclining a front side 3f of a thermal decomposition vessel 2 to heat and thermally decompose waste plastics P, said 3 being partitioned by a partitioning part 7 to form a thermal decomposition chamber Rf in front, a liquefying chamber Rr behind and a Rf-Rr connecting space Rc below, as regards 7 respectively, at a specific interval in the vertical and horizontal directions inside 3, wherein a multiple number of heating tubes 4a-4f having ventilation conduits 8 in the longitudinal direction are installed between a front connecting space Cf which is insulated from the outer atmosphere and 7, between a rear connecting space Cr which is insulated from the outer atmosphere and 7 and between Cf and Cr located below 7 (4c and 4d), respectively. 4a and 4b located between Cf and 7 are connected to a hot air generator 21, and 4e and 4f located between Cr and 7 are connected to a chimney 22 which is connected to the outer atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste plastic oil reduction apparatus for recycling waste plastic.

[0002]

2. Description of the Related Art Conventionally, waste plastic (polymer waste)
There is known an oil-reducing device that heats and thermally decomposes and then reduces it to heavy oil (corresponding to heavy oil A).

[0003] This type of oil-reducing device is made of polyethylene,
Solid waste plastics such as polysterol and vinyl chloride are melted in a melting tank heated at a relatively low temperature of around 250 ° C. (70 ° C. for vinyl chloride), and then 400 ° C.
The waste plastic dissolved in a pyrolysis tank heated to a high temperature (around 170 ° C. for vinyl chloride) is thermally decomposed, and the decomposed gas is cooled to obtain heavy oil. In addition,
If solid waste plastic is directly injected into the pyrolysis tank, not only will the waste plastic be carbonized and the reduction efficiency will be greatly reduced, but also the treatment of carbides will be difficult. Dissolves solid waste plastic.

[0004]

However, the above-mentioned conventional waste plastic oil reduction apparatus has the following problems to be solved.

First, since a separate dissolving tank is required in addition to the thermal decomposition tank, the entire apparatus becomes complicated and large, the cost is greatly increased, and the maintenance is extremely disadvantageous. .

[0006] Second, the processing speed of waste plastics is reduced, the productivity of heavy oil is reduced, and the economical efficiency during production is poor.

The present invention has been made to solve the problems existing in the prior art, and realizes simplification and downsizing of the whole apparatus, drastic cost reduction and ease of maintenance, and production. It is an object of the present invention to provide a waste plastic oil reduction apparatus capable of dramatically improving efficiency and economy.

[0008]

In order to achieve the above object, the construction of the present invention comprises a waste plastic P.
.. In the liquefaction reduction apparatus 1 for waste plastics P... Provided with a pyrolysis tank 2 for pyrolyzing by heating
The tank body 3 has a bottom surface 3d side narrowed by inclining f, and a partition section 7 is provided inside the tank body 3 so that the front of the partition section 7 is defined as a pyrolysis chamber Rf, and the partition section 7 is provided. 7 is defined as a melting chamber Rr, and a lower part of the partition 7 is defined as a communication space Rc between the thermal decomposition chamber Rf and the melting chamber Rr, and is defined inside the tank body 3 in the vertical and horizontal directions. A plurality of heating tubes 4a..., 4b.
, 4d, 4e, 4f,... between the front communication space Cf, which is isolated from the outside, and the partition 7, and the rear communication space Cr, which is isolated from the outside. Between part 7
And between the front communication space Cf and the rear communication space Cr (4c..., 4d...) Below the partition portion 7, and between the front communication space Cf and the partition portion 7 (4a.・ 、
4b...) Are connected to the hot air generator 21 and between the rear communication space Cr and the partition 7 (4e.
f) is composed of a waste plastic oil reduction device based on the fact that the heating pipe at the point f is connected to the chimney 22 communicating with the outside of the pyrolysis tank 2.

In the above construction, the heating pipes 4a..., 4b.
Are connected to the hot air generator 21, but in the normal case, the uppermost heating pipes 4 a are connected to the hot air generator 21. On the other hand, heating pipes 4e..., 4f...
Are connected to the hot air generator 21, but in the normal case, the uppermost heating pipes 4 f are connected to the external chimney 22. That is, the uppermost heating tube 4
.., 4f... are conveniently connected to the hot air generator 21 and the chimney 22, respectively, from a design standpoint, but this point is not necessarily an essential requirement of the present invention.

When the above-mentioned design is adopted, the heating tubes 4a... Are set to the highest temperature, the heating tubes 4f. , 4b ... are set to a temperature at which pyrolysis is possible, while the heating tubes 4c ..., 4d ..., 4e ...
, 4f... Can be set to a temperature at which the waste plastic P.

In the above construction, the solid waste plastics P... Introduced into the melting chamber Rr are heated by the relatively low-temperature heating tubes 4f. Heats and dissolves. On the other hand, the dissolved waste plastic L reaches the thermal decomposition chamber Rf through the communication space Rc. As the level of the dissolved waste plastic L increases, the liquid level reaches the upper part of the pyrolysis chamber Rf. If the liquid level reaches the high-temperature heating pipes 4a,. 4a, and is vaporized by thermal decomposition. In addition, the vaporized decomposition gas is cooled,
It is liquefied into heavy oil (equivalent to heavy oil A).

Therefore, since the pyrolysis tank 2 also serves as a melting tank, simplification of the whole apparatus and downsizing can be realized.
In addition to greatly reducing costs, facilitating maintenance, and increasing the processing speed of waste plastic, the productivity of heavy oil and the economics during production can be improved. In addition, in the said structure, although the tank main body 3 made the front part 3f incline and made the bottom part side narrow as shown in FIG. 1, this melt | dissolved even when the apparatus was not operating. Waste plastic L
When heating from the bottom of the bottom part, by designing the area of the bottom part small, to perform efficient heating, and
During the operation of the apparatus, the front pyrolysis chamber Rf
In the above, after the melted waste plastic L moving through the communication space Rc reaches the pyrolysis chamber Rf, the specific gravity decreases as the molten state changes from the melted state to the pyrolyzed state, and the volume increases when the melted plastic rises. It is derived from considering that

[0013]

Next, preferred embodiments according to the present invention will be described in detail with reference to the drawings.

First, the configuration of the waste plastic oil reduction apparatus 1 according to the present embodiment will be described with reference to FIGS.

In the figure, reference numeral 2 denotes a pyrolysis tank which constitutes a main part of the oil conversion apparatus 1.

A partition 7 is provided between the left surface 3p and the right surface 3q at an intermediate position in the front-rear direction inside the tank body 3.
Erection. The partition 7 is formed as a closed body having a hollow inside. A partition 9 is provided inside the partition 7, and the partition 9
Before and after are formed a front space Sf and a rear space Sr. Therefore,
A pyrolysis chamber Rf is formed in front of the partition 7, a melting chamber Rr is formed in the rear of the partition 7, and a communication space Rc is formed below the partition 7.

On the other hand, a lower portion of the outer surface of the tank body 3 is surrounded by an outer plate 4, and a heat retaining portion 32 having a closed space between the outer plate 14 and the tank body 3 is provided. Heat retaining oil w is supplied to the heat retaining section 32 from a heating device 31 described later. Further, the tank main body 3 including the outer plate 14, the front communication space Cf, and the rear communication space Cr are covered by the outer housing 13, and the front communication space Cf is located between the front portion 3f of the tank main body 3 and the outer housing 13. The rear communication space Cr is located between the rear surface 3r of the tank body 3 and the outer housing 13.

At the uppermost stage of the thermal decomposition chamber Rf, four heating tubes 4a... Arranged at predetermined intervals in the left-right direction are provided, and the front end openings of the heating tubes 4a. At the same time, the rear end opening (inner end opening) communicates with the front space Sf in the partition 7. Further, in the second stage from the top of the pyrolysis chamber Rf, four heating pipes 4b... Arranged at predetermined intervals in the left-right direction are provided, and the front end openings of the heating pipes 4b. At the rear end opening (inner end opening)
Is connected to the front space Sf. Further, in the third stage and the lowermost stage from the top of the pyrolysis chamber Rf, four heating tubes 4c... And 4d.
Is provided. In this case, the heating tubes 4c ... and 4d ...
Penetrates the thermal decomposition chamber Rf, the communication space Rc, and the melting chamber Rr, and the openings at both ends of the heating tubes 4c.
It faces the front communication space Cf and the rear communication space Cr.
Further, at the uppermost stage of the melting chamber Rr, four heating tubes 4f... Arranged at predetermined intervals in the left-right direction are provided, and the heating tubes 4f.
The front end opening (inner end opening) is connected to the rear space Sr in the partition 7 and the rear end opening faces the outside of the outer housing 13. Further, in the second stage from the top of the melting chamber Rr, four heating tubes 4e arranged at predetermined intervals in the left-right direction.
The front end opening (inner end opening) of the heating tube 4e... Is connected to the rear space Sr in the partition 7 and the rear end opening faces the rear communication space Cr. In addition, each heating tube 4a
.., 4b ..., 4c ..., 4d ..., 4e ...
.., 4f... Are set to about 10 to 15 cm.

Thus, the heating tube 4a... → the front space S
f → heating pipe 4b ... → front communication space Cf → heating pipe 4c
・ ・ And 4d ・ ・ ・ → Back communication space Cr → Heating tube 4e ・ ・
A continuous ventilation path 8 is constituted by a path from the rear space Sr to the heating pipe 4f.

At the upper end of the melting chamber Rr, a hopper 1 for charging solid waste plastics P.
2 is provided. Further, reference numeral 15 denotes a cover for covering the upper surface of the tank main body 3, and a duct 16 for collecting the decomposition gas is connected to the upper center of the cover 15. This duct 16 is connected to a scrubber 52 described later.

On the other hand, the outer end openings of the heating tubes 4a...
are connected to a chimney 22 provided with blowers 23. Thereby, the hot air H supplied from the hot air generator 21 is discharged to the outside from the chimney 22 via the ventilation path 8. At this time, the temperature of the heating tubes 4a... Arranged above the thermal decomposition chamber Rf is set to the heating tubes 4d... 4c.
To be higher. That is, the heating pipe 4a arranged on the upstream side
The heating pipe 4f arranged downstream with respect to the temperature of ...
Are gradually lowered due to heat radiation when the hot air H passes through the ventilation paths 8. Therefore, the temperature of the heating pipes 4a... Arranged at the uppermost part is equal to the temperature at which the dissolved waste plastic L is thermally decomposed (normally 400 ° C.,
° C), the heating pipes 4c,.
, 4b,..., 4c... so that the temperature of d...・ 、
The conditions such as the diameter, length, number, interval, etc. of 4d, 4e, 4f, are selected.

The outer peripheral surface of the heating tubes 4a,.
The surface that is in contact with the dissolved waste plastic L and the decomposed gas, such as the inner surface, is heat-resistant liquefied glass (normal temperature glass).
Is applied. Since the heating pipes 4a,... And the tank body 3 are usually made of a metal material such as steel, corrosion is likely to occur due to oxidation or the like accompanying heating. In particular, when vinyl chloride is used as the waste plastic, corrosion and oxidation of the metal proceed at a considerable rate due to the generated chlorine. For this reason, the surfaces of the heating tubes 4a, etc. are coated with liquefied glass 25a, and the chemical resistance, corrosion resistance, durability and the like are improved. In this case, as shown in FIG. 3, for example, the liquefied glass 2 is placed on the surface of the heating tube 4a.
It is desirable to apply 5a, 25b,.

The thermal decomposition tank 2 is provided with a heat retaining device 30 shown in FIG. The heat retaining device 30 includes a heating device 31. The heating device 31 includes a heating unit 33, and the heating unit 3
2 and 5, the discharge section 3 is connected to one side of the heat retaining section 32 via a pipe 35 having a valve 34, and the suction section of the heating section 33 is connected to a pipe 37 having a valve 36. It connects to the other side of the heat retaining section 32 through the above. Thus, after the heat retaining oil W is heated by the heating unit 33, the outer plate 1 forming the heat retaining unit 32 via the pipe 35.
While being supplied to the space between the tank body 4 and the tank body 3, the heating oil W in the space is returned to the heating unit 33 through the pipe 37 to form a heating circulation circuit. 38 is a valve 39
, An oil tank connected to the heating unit 33, a control unit 40 for controlling the operation of the heating unit 33 and various controls such as a heating temperature, and an extension unit 41 having a function of liquefying the vaporized heat retaining oil.

FIG. 4 shows an oil-reducing apparatus 1 having a pyrolysis tank 2.
1 shows the entire configuration. In the figure, 51 is a crusher for crushing large waste plastics into small pieces, 52 is a scrubber for neutralizing chlorine gas, 53 is a PH adjustment tank attached to the scrubber, and 54 is a condenser for liquefying decomposed gas. And 55, a cooler (cooling tower) for cooling the condenser 54, 56, a pump, 57, an oil / water separation tank for separating the obtained heavy oil and water, 58, a filter, and 59, a heavy oil storage tank.

Next, the overall operation of the liquefaction and reduction apparatus 1 including the function of the pyrolysis tank 2 constituting the main part of the present embodiment will be described with reference to the drawings.

First, hot air H is supplied by the hot air generator 21 to the heating tubes 4a. FIG. 1 shows the path of the hot air H by arrows. Thereby, the heating tubes 4a...
Is heated to around 400 ° C (170 ° C for vinyl chloride). Also, heating tubes 4c..., 4d.
Is heated to around 250 ° C. (70 ° C. for vinyl chloride). Then, the hot air H that has passed through the ventilation path 8 is discharged from the chimney 22 to the outside. At this time, the air is sucked by the blower 23.

On the other hand, solid waste plastics (polyethylene, polysterol, vinyl chloride, etc.) P are put into the hopper 12. At this time, the large waste plastic is crushed into small pieces by the crusher 51. The solid waste plastics P... Charged in the hopper 12 are in the melting chamber Rr.
Supplied inside.

The waste plastic P supplied into the melting chamber Rr falls to the bottom of the melting chamber Rr and is heated by the relatively low-temperature heating pipes 4c, 4d,. Dissolve. Dissolved waste plastic L is connected to communication space R
c and into the pyrolysis chamber Rf,
Stored inside. As the dissolved waste plastic L increases, the liquid level reaches the upper part of the pyrolysis chamber Rf, so that the liquid level rises to the high-temperature heating pipe 4a disposed above the pyrolysis chamber Rf.
.. Are heated by the heating tubes 4a and vaporized by thermal decomposition.

On the other hand, the vaporized decomposition gas is supplied to the scrubber 52 through the duct 16, and the mixed chlorine gas is neutralized. Further, the cracked gas is supplied from the scrubber 52 to the condenser 54 and cooled to be liquefied into heavy oil (equivalent to heavy oil A). The condenser 54 is constantly cooled by the cooling liquid sent from the cooler 55. Then, the obtained heavy oil is supplied to the oil / water separation tank 57. In the oil / water separation tank 57, water and heavy oil are separated, and the heavy oil is filtered by the filter 5.
After the impurities are removed by the hot air generator 8, the hot air generator 2 is supplied to and stored in the storage tank 59.
1 and used as fuel for the hot air generator 21.

During the period in which the operation of the liquefaction reduction apparatus 1 is stopped at night or the like, the tank body 3 is kept warm by the heat keeping device 30. In this case, the heat retaining oil W is heated by the heating unit 33 to a temperature of 70 to 400 ° C.
5 and is supplied to the space between the outer plate 14 and the tank main body 3 constituting the heat retaining section 32 and the oil W for heat retention in the space.
Is returned to the heating unit 33 via the pipe 37. Thereby, the waste plastic L remaining in the tank main body 3 is kept warm, and the start-up time at the time of operation reunion can be greatly reduced.

The embodiment has been described in detail above.
The present invention is not limited to such an embodiment, and can be arbitrarily changed in the configuration, shape, material, quantity, method, and the like of the details without departing from the gist of the present invention.

[0032]

As described above, the oil-reducing apparatus for waste plastic according to the present invention has a tank body having a front portion inclined and a bottom portion narrowed, and a partition portion is provided inside the tank body. Thereby, a pyrolysis chamber is formed forward from the partition, a melting chamber is formed rearward from the partition, and a communication space is formed below the partition, and a predetermined space is formed inside the tank body in the vertical and horizontal directions. A plurality of heating pipes having a ventilation path in the front-rear direction and provided in each of the heating pipes, and the temperature of the heating pipes arranged in the upper part of the thermal decomposition chamber is set higher than the heating pipes arranged in the melting chamber. The provision of the tank has the following remarkable effects.

Since the thermal decomposition tank also serves as a melting tank, it is possible to realize simplification and downsizing of the entire apparatus, and also to achieve drastic cost reduction and easy maintenance.

Since the processing speed for waste plastics is increased, the productivity of heavy oil and the economics during production can be dramatically improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional side view of a pyrolysis tank constituting a main part of an oil reduction apparatus according to the present embodiment,

2 is a sectional front view taken along line XX in FIG. 1;

FIG. 3 is a partial cross-sectional view of a heating tube in the pyrolysis tank,

FIG. 4 is a block diagram showing an overall configuration of the oil-reducing device.

FIG. 5 is a block diagram of a heat retaining device provided in the oil-reducing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Oil reduction apparatus 2 Pyrolysis tank 3 Tank main body 3f Front part of tank main body 3d Bottom part of tank main body 4a ・ ・ ・ Heating tube 4b ・ ・ ・ Heating tube 4c ・ ・ ・ Heating tube 4d ・ ・ ・ Heating tube 4e ・..Heating tube 4f ・ ・ ・ Heating tube 7 Partition 8 Air passage P ・ ・ ・ Waste plastic Rf Pyrolysis room Rr Melting room Rc Communication space L Melted waste plastic H Hot air

Claims (3)

[Claims] 1. A waste plastic oil liquefaction reduction device having a pyrolysis tank for heating and thermally decomposing waste plastic, comprising a tank main body having a front part inclined and a bottom part side narrowed. By providing a partition inside, the front of the partition is a pyrolysis chamber, the back of the partition is a melting chamber, and the lower part of the partition is formed as a communication space between the pyrolysis chamber and the melting chamber. A plurality of heating pipes arranged at predetermined intervals in the up-down direction and the left-right direction inside the tank main body, and having a ventilation path in the front-rear direction, between the front communication space and the partition, which are isolated from the outside. Heating is provided between the front communication space and the partition portion between the front communication space and the rear communication space below the partition portion and between the front communication space and the rear communication space below the partition portion. The pipe is connected to the hot air generator and An oil reduction device for waste plastics based on the fact that a heating pipe between a communication space and a partition is connected to a chimney communicating with the outside of a pyrolysis tank. 2. The upper part of the pyrolysis chamber is connected to a scrubber for neutralizing chlorine gas, the scrubber is connected to a condenser interlocked with a cooling device, and the condenser is connected to an oil / water separation tank. The waste plastic oil reduction apparatus according to claim 1, wherein: 3. The waste plastic oil reduction apparatus according to claim 2, wherein the oil / water separation tank is connected to the storage tank and the hot air generator via a filter.