JP2922760B2 - Waste plastic oil production facility - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for melting waste plastic in a waste plastic treatment facility for melting and decomposing a waste plastic material to obtain a low molecular weight hydrocarbon compound.

[0002]

2. Description of the Related Art Conventionally, as a means for melting and decomposing a waste plastic material, for example, there is a method described in Japanese Patent Publication No. 3-86691.

According to this method, as shown in FIG. 7, a waste plastic crushed material A obtained by a crushing device is heated and kneaded by an extruder (ruder) 1 to be primarily melted, and then supplied to a raw material mixing tank 2. The primary melt B is secondarily melted and decomposed in the raw material mixing tank, the primary melt B is supplied to the pyrolysis tank 3, and a vaporized product of the melt is catalytically converted into a low-molecular hydrocarbon compound in the catalytic cracking tank 4. .

[0004] As described above, the plastic material supplied to the pyrolysis tank 3 in this conventional method is firstly melted by the extruder (ruder) 1 and then mixed with the raw material mixing tank 2.
The raw material is secondarily melted and decomposed in
In a uniform molten and decomposed state to achieve a stable pyrolysis process.

[0005]

However, when waste plastic material contains a large amount of vinyl chloride,
In this extruder, a large amount of hydrogen chloride gas is generated, and in the coexistence of water contained in the raw materials, the hydrogen chloride gas is condensed to form hydrochloric acid in a low temperature part of the extruder. Materials have to be applied and must be expensive.

Further, in order to prevent deterioration of oil quality due to mixing of hydrogen chloride into product oil, a large amount of hydrogen chloride gas generated in the extruder, which is a former stage, is completely sucked from the inside of the extruder to the outside. In order to do so, the length of the extruder in the axial direction must be extremely long, and the waste plastic material that has been primarily melted in the extruder must be stirred and stagnated for a long time. During the continuous processing of the waste plastic processing equipment as a whole, while the facility cost of the extruder is extremely increased, the long stirring / flow time in the extruder hinders the smooth continuous processing. For this reason, conventionally, the axial length of the extruder is set to an appropriate axial length so that continuous processing with an emphasis on productivity can be smoothly performed.

[0007] As a result, hydrogen chloride is generated from the molten plastic in the raw material mixing tank and the pyrolysis tank, for example, after the extruder, and this is mixed into the oil of the product. Therefore, dechlorination means such as a dechlorination tank is required. Met.

Further, in order to melt and knead the waste plastic material in the extruder, a large driving force is required because the viscosity of the waste plastic material melted in the extruder is high.

As described above, in the conventional extruder, as described above, the extruder must be made of an expensive corrosion-resistant material that can withstand hydrogen chloride.

[0010] Separate dechlorination means is required for equipment downstream of the extruder.

[0011] A large amount of power is required during operation.

There are various problems such as:

Therefore, if the primary melting by the extruder can be omitted, not only the equipment cost and operation cost of the entire waste plastic processing facility can be reduced, but also the construction process can be shortened, and the advantages are great.

However, simply omitting the extruder sufficiently mixes the waste plastic crushed material A charged into the raw material mixing tank at room temperature with the liquid plastic melt supplied from the pyrolysis tank. It takes time and effort to obtain a homogeneous melt, which leads to a decrease in productivity and oil quality, and it is necessary to take measures against corrosion of equipment due to the generation of a large amount of hydrogen chloride gas due to the heating of vinyl chloride. There is
In terms of equipment cost, it is inevitably more expensive than the conventional one provided with an extruder.

An object of the present invention is to provide a low-molecular hydrocarbon compound by melting / decomposing a raw material waste plastic material, in which the raw material is melted / decomposed / oiled without using a primary melting device such as an extruder. In addition, measures shall be taken to ensure that continuous operation of the entire waste plastic processing facility is smoothly performed and that no deterioration in oil quality occurs and that no hydrochloric acid corrosion damage occurs due to condensation of hydrogen chloride gas generated by decomposition of vinyl chloride in raw materials. To provide.

[0016]

According to the present invention , at least two or more raw material mixing tanks having a waste plastic inlet at the top are provided , and a pyrolysis tank and a catalytic cracking tank are provided downstream of the raw material mixing tank. The tanks are connected in series, and the pyrolysis tank and the plurality of raw material mixing tanks are connected so as to alternately circulate the contents of both, and the raw material mixing tank has a stirring means and / or self-circulation of the contents. in Yuka manufacturing facility waste plastic obtained by respectively arranged means for removing the hydrogen chloride is provided with the means
There is .

[0017]

The waste plastic raw material is alternately processed by the plurality of raw material mixing tanks A and B and is continuously supplied to the pyrolysis tank. As a result, the waste plastic oil production facility is continuously operated. Can be processed.

In the raw material mixing tank, particularly, hydrogen chloride and the like contained in the waste plastic raw material can be completely removed.

As described above, the extruder can be omitted.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an overall schematic diagram of a waste plastic oil treatment apparatus according to the present invention.

In the figure, 2 is a raw material mixing tank, 3 is a pyrolysis tank, 4
Is a catalytic cracking tank, 5 is a pump, 6 is a valve, 7 is an exhaust fan,
8 is a washing tower as a means for removing hydrogen chloride, 9 is an inlet for the waste plastic raw material into the raw material mixing tank, 10 is a rotary stirrer as a stirring means, and 12 is a self-circulating means by a melting pump in the raw material mixing tank. Is shown.

The above-mentioned main components constitute the waste plastic oil treatment equipment of the present invention.

2 to 5, a method of liquefying waste plastic using the waste plastic liquefaction equipment of the present invention will be described.

In FIGS. 2 to 5, the open / closed state of the valve 6 is indicated by ◇ as open and ◆ as closed in each drawing.

<Step 1> Referring to FIG. 2, waste plastic raw material previously cut and crushed by a crushing machine or the like is introduced into raw material mixing tank A, and waste plastic raw material input port 9 is opened and opened. Then, the inlet 9 is closed. Next, a pyrolysis oil of about 400 to 450 ° C. is carried into the raw material mixing tank A from the pyrolysis tank 4.

In the raw material mixing tank A, the input waste plastic raw material is supplied from the pyrolysis tank 4 to about 400-45.
It is melted by the pyrolysis oil at 0 ° C. At this time, in order to promote melting and renew the surface of the molten plastic, the rotary stirrer 10 is rotated or the melt in the raw material mixing tank A is circulated by the self-circulation means.

The melting and reaction temperature in the raw material mixing tank A is about 2
The temperature is 50 to 350 ° C. Therefore, when PVC is not mixed in the raw material of the waste plastic, about 1 hour or more, and when PVC is mixed, the temperature is maintained for about 3 to 5 hours or more. Then, particularly, all the hydrogen chloride contained in the input waste plastic raw material is removed. The separated hydrogen chloride is sent to a washing tower, where it is rendered harmless, and then released into the atmosphere.

<Step 2> Referring to FIG. 3, on the other hand, in the raw material mixing tank B, preferably after about half of the required melting and mixing time in the raw material mixing tank A, The same processing as in the raw material mixing tank A is performed.

More specifically, the raw plastic material cut and crushed by a crusher or the like in advance is mixed with a raw material mixing tank B.
Then, the input port 9 of the waste plastic raw material is opened and charged into the inside, and then the input port 9 is closed. Next, a pyrolysis oil of about 400 to 450 ° C. is carried into the raw material mixing tank B from the pyrolysis tank 4.

In the raw material mixing tank B, the input waste plastic raw material is supplied from the pyrolysis tank 4 to about 350 to 40.
It is melted by the pyrolysis oil at 0 ° C. At this time, in order to promote melting and renew the surface of the molten plastic, the rotary stirrer 10 is rotated or the melt in the raw material mixing tank B is circulated by the self-circulating means. .

The melting and reaction temperature in the raw material mixing tank B is about 2
The temperature is 50 to 350 ° C. Therefore, when PVC is not mixed in the raw material of the waste plastic, about 1 hour or more, and when PVC is mixed, the temperature is maintained for about 3 to 5 hours or more. Then, particularly, all the hydrogen chloride contained in the input waste plastic raw material is removed.

The separated hydrogen chloride is sent to a washing tower to be rendered harmless, and then released into the atmosphere.

<Step 3> Referring to FIG. 4, after transporting the pyrolysis oil to the raw material mixing tank B, in the raw material mixing tank A,
After the melting and reaction of the mixture are completed, that is, after all the hydrogen chloride contained in the waste plastic raw material is completely removed, the molten plastic is returned to the pyrolysis tank 4. Pyrolysis tank 4
The pyrolysis reaction of the molten plastic is maintained at about 400 to 450 ° C. by an external heating means, and the pyrolysis gas is conveyed to the catalytic cracking tank 4 arranged on the downstream side to be turned into oil. You.

<Step 4> Raw material mixing tank A whose interior is empty
, The <Step 1> is repeated.

<Step 5> After the pyrolysis oil is conveyed to the raw material mixing tank A, the melting and reaction of the mixture is completed in the raw material mixing tank B, that is, all the hydrogen chloride contained in the waste plastic raw material is completely removed. After being separated, the molten plastic is returned to the pyrolysis tank 4. The pyrolysis tank 4 is maintained at about 400 to 450 ° C. by an external heating means to promote the pyrolysis reaction of the molten plastic, and the pyrolysis gas is transported to the catalytic cracking tank 4 arranged on the downstream side. And oiled.

<Step 6> A raw material mixing tank B having an empty interior
The <Step 2> is repeated.

By repeating the above steps 1 to 5 in the raw material mixing tank A and the raw material mixing tank B, it is possible to continuously and stably perform pyrolysis in the pyrolysis tank 4. Continuous stable oiling is possible.

FIG. 5 is a diagram illustrating the above steps.

In the present embodiment, the number of the raw material mixing tanks A and B is set to two and used. However, during the continuous processing, the raw plastic mixing tank is included in the waste plastic raw material charged into the raw material mixing tank. In particular, when the amounts of hydrogen chloride and the like are different, it is possible to easily cope with the continuous processing by providing another extra raw material mixing tank.

FIG. 6 shows each step in this case.

By increasing the residence time of the waste plastic in the melting / mixing tank, it is possible to obtain a high removal rate of hydrogen chloride from the plastic containing a large amount of hydrogen chloride.

[0042]

【The invention's effect】

(1) In the raw material mixing tank, it is possible to completely remove particularly hydrogen chloride and the like contained in the waste plastic raw material,
Equipment for removing dehydrochloride and the like is not required on the downstream side, and dehydrochloride and the like are not mixed during the oilification of the product, so that the quality of the product is high and stable.

(2) Even if an extruder that is expensive and complicated to maintain is not used, continuous processing can be performed by adding one raw material mixing tank that is inexpensive and easy to maintain.

[Brief description of the drawings]

FIG. 1 is an overall schematic view of a waste plastic oil treatment apparatus of the present invention.

FIG. 2 is a process explanatory view of an oil treatment method using the waste plastic oil treatment equipment of the present invention.

FIG. 3 is a process explanatory view of an oil treatment method using the waste plastic oil treatment equipment of the present invention.

FIG. 4 is a process explanatory view of an oil treatment method using the waste plastic oil treatment equipment of the present invention.

FIG. 5 shows a simplified process diagram in raw material mixing tanks A and B.

FIG. 6 shows a simplified process diagram in raw material mixing tanks A, B, and C.

FIG. 7 shows an overall schematic diagram of a conventional oil treatment apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 extruder 2 raw material mixing tank 3 thermal decomposition tank 4 catalytic cracking tank 5 pump 6 valve 7 exhaust fan 8 washing tower 9 raw material inlet 10 rotary stirrer 11 self-circulation means

──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Nobuyuki Mikata 46-59 Ohara Nakahara, Tobata-ku, Kitakyushu-shi, Fukuoka Nippon Steel Corporation Machinery & Plant Business Department (72) Inventor Takaharu Takeuchi Tobata-ku, Kitakyushu-shi, Fukuoka 46-59 Ohara Nakahara Nippon Steel Corporation Machinery & Plant Division (72) Inventor Wataru Shiramizu 59 Nippon Steel Plant Design Co., Ltd., 46 Ohara Nakahara, Tobata-ku, Kitakyushu, Fukuoka Prefecture (56) References 49-66776 (JP, A) JP-A-48-26869 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C10G 1/10 B09B 3/00 C08J 11/12

Claims (1)

(57) [Claims] At least two or more raw material mixing tanks having a waste plastic inlet at an upper portion thereof are disposed, and a pyrolysis tank and a catalytic cracking tank are connected in series on a downstream side of the raw material mixing tank,
The pyrolysis tank and the plurality of raw material mixing tanks are connected so as to alternately circulate the contents of both, and the raw material mixing tank is provided with a means for stirring the contents and / or a means for self-circulation, while removing hydrogen chloride. Yuka production equipment waste plastic obtained by respectively disposed means.