JPH07286185A - Method for treating mixed waste plastics and system therefor - Google Patents

Abstract

PURPOSE:To provide a mixed waste plastics-treating method intended for waste volume reduction and resource reclamation, capable of raising the decomposition rate of thermosetting resins hard to pyrolyze and gasify without the need for sorting mixed waste plastics, and designed to recover oil relatively rich in low-carbon number components. CONSTITUTION:Mixed waste plastics are fed from a reservoir 1 to a dissolving pyrolysis oven 2 where they are mixed with a solvent fed from an oil reservoir 5 and then heated to effect evaporation of the low-boiling solvent and pressurization of the oven along with dissolution of part of the waste plastics. Subsequently, by pyrolysis and gasification of the solvent and both the dissolved and undissolved mixed waste plastics the oven is pressurized to the pyrolysis pressure, and under this pressure the pyrolysis and gasification are further carried out. The resultant pyrolysis gas discharged from the oven is introduced into a catalytic cracking oven 3 where the gas is cracked by catalytic reaction. The resultant cracked gas is condensed and liquefied in a condenser 3, and the liquefied oil component is reserved in the oil reservoir 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating waste, and more particularly to a method for recycling and reducing the volume of discarded plastic.

[0002]

2. Description of the Related Art With the recent increase in plastic production, the amount of waste is increasing year by year. Currently, most of the waste plastic is disposed of by landfill and incineration. However, there are problems of shortage of landfill site, and in the case of incineration, there is a problem of short life of incinerator and environmental pollution due to exhaust gas. In order to solve these problems, methods of recycling waste plastics and recovering energy have been studied.

For reducing the volume and recycling of combustibles, especially polymer wastes of plastics, for example, a method of melting and pyrolyzing thermoplastic plastics to recover and recover them and use them as fuels is available. JP-A-49-17477
JP-A-59-174689 and the like. Furthermore, regarding the treatment of mixed polymer waste such as thermoplastics and thermosetting plastics such as plastics, rubbers, paints, lubricating oils, fats, asphalt, pitch, synthetic fibers, natural fibers organic synthetic solids, mixed polymers There is a method and a treatment device for burning a part of the waste and heat-treating the remaining polymer waste by the heat, that is, for gasifying the polymer waste by the partial oxidation combustion / dry distillation pyrolysis method or recovering the oil content. It is disclosed in Japanese Patent Publication No. 2-5796.

There is also a method of recycling waste plastic into the petroleum-based oil which is the original raw material. Plastics are roughly classified into thermoplastic resins and thermosetting resins. Wastes of thermoplastic resins that have the property of melting and decomposing by heating are subjected to heat treatment to be recycled as fuel oil and the like. It is disclosed in Japanese Unexamined Patent Publication No. 48-60777. On the other hand, thermosetting resins are generally considered to be difficult to heat-treat due to their high melting point and high heat resistance.

However, in general, a waste plastic contains a mixture of a thermoplastic resin and a thermosetting resin having different properties as described above. As a method for thermally decomposing the mixed waste plastic, a thermoplastic resin is used. A method of separately treating by utilizing the difference in melting point from the thermosetting resin is disclosed in JP-A-3-21.
It is disclosed in Japanese Patent No. 2491. In this method, waste plastic is melted in its decomposed oil at about 250 to 280 ° C., and then the unmelted component containing a thermosetting resin as a main component
Although it is a method of decomposing at a high temperature of 00 to 700 ° C., it has a drawback that it consumes a lot of energy because of high processing temperature.

[0006]

Among the waste plastics, the thermosetting resin, in particular, is decomposed by the heat treatment, but the other part is not decomposed to form a network structure, which is irreversibly hardened to form a solid residue. It has the following properties. The thermal decomposition characteristics of such a thermosetting resin vary depending on the heat treatment conditions. That is, by devising the heat treatment conditions, the curing of the resin can be suppressed and the decomposition rate can be improved. The treatment method described in JP-A-3-212491 described above substantially treats the thermosetting resin and the thermoplastic resin individually, and further devises for improving the decomposition rate of the thermosetting resin. It is considered necessary. Further, the decomposition temperature of the thermosetting resin is often higher than that of the thermoplastic resin,
Therefore, there is a problem that energy consumption during the decomposition process increases.

The object of the present invention is to promote the thermal decomposition of the thermosetting resin in the treatment of the mixed waste plastic of the thermosetting resin and the thermoplastic resin and to recover the oil containing a large amount of low carbon number in total. It is to provide a possible processing method.

[0008]

In order to achieve the above object, the method for treating mixed waste plastic of the present invention is to mix the mixed waste plastic of thermosetting resin and thermoplastic resin with a solvent in a closed container, It is characterized in that the solvent is gasified by heating to increase the pressure, the mixed waste plastic is dissolved under the increased pressure, and the solvent and the dissolved and insoluble mixed waste plastic are pyrolyzed and gasified.

In the mixed waste plastic treatment method of the present invention, the mixed waste plastic of the thermosetting resin and the thermoplastic resin is mixed with the solvent in the first closed container, and the solvent is gasified by heating. Increase the pressure in the closed container of
The mixed waste plastic is dissolved in the first closed container maintained at a predetermined pressure, and then the solvent and the dissolved and insoluble mixed waste plastic in the first closed container are transferred to the second closed container. The solvent and the dissolved and insoluble mixed waste plastics are heated in the second closed container, and the pressure in the second closed container is increased by gasifying the solvent and the thermal decomposition gasification of the dissolved and insoluble mixed waste plastics. It is characterized in that the solvent and the dissolved and insoluble mixed waste plastic in the second closed container maintained at the pressure of 1 are thermally decomposed and gasified.

As the solvent, any solvent capable of dissolving the mixed waste plastic can be used, and for example, oil produced by processing the mixed waste plastic or other petroleum-based oil can be used. It is suitable that the mixed waste plastic is dissolved and pyrolyzed and gasified under a gauge pressure of 2 atm or more, preferably a gauge pressure of 5 atm or more.

The method for treating mixed waste plastics according to the present invention comprises a storage means for storing the mixed waste plastics, a dissolution pyrolysis gasification means for the mixed waste plastics connected to the storage means, a solvent storage means, and a solvent storage means. Means for supplying the solvent to the dissolution pyrolysis gasification means, means for maintaining the inside of the dissolution pyrolysis gasification means at a predetermined temperature, and the pressure inside the dissolution pyrolysis gasification means to a predetermined pressure of a gauge pressure of 2 atm or more. Pressure maintaining means for maintaining, lightening means for lightening the gas discharged from the melt pyrolysis gasification means, means for cooling and liquefying the gas lightened by the lightening means, and means for storing liquefaction And a means for discharging undecomposed substances in the melt pyrolysis gasification means, by means of a treatment apparatus for mixed waste plastics.

Further, the method for treating mixed waste plastics according to the present invention comprises a storage means for storing the mixed waste plastics, a dissolution means for the mixed waste plastics connected to the storage means, a solvent storage means, and a solvent storage means to a solvent. Means for supplying the melting means to the melting means, means for maintaining the inside of the melting means at a first predetermined temperature, first pressure maintaining means for maintaining the pressure inside the melting means at a predetermined pressure of 2 atm or more of gauge pressure, and melting Means for melting and pyrolyzing and gasifying the mixed waste plastics connected to the means, means for maintaining the inside of the melting and pyrolyzing gasification means at a second predetermined temperature higher than the first temperature, A second pressure maintaining means for maintaining the pressure at a predetermined pressure of 2 atm or more, a lightening means for lightening the gas discharged from the melting means and the melting pyrolysis gasification means, and a lightening means for lightening the gas. It Means for gas cooled liquefied was,
It is carried out by an apparatus for treating mixed waste plastic, which comprises a means for storing a liquefied material and a means for discharging an undecomposed material in a melting pyrolysis gasification means. The pressure maintaining means,
The pressure detecting means, the valve means, and the control means for controlling the opening / closing of the valve means based on the detection signal from the pressure detecting means.

[0013]

According to the mixed waste plastic treatment method of the present invention, since the mixed waste plastic is mixed with the solvent and pyrolyzed under high pressure, a part of the mixed waste plastic is dissolved, and this solution is used as a heat medium or a reaction medium. In particular, the pyrolysis gasification at a relatively low temperature of the organic resin of the thermosetting plastic, which is difficult to gasify by single pyrolysis, is promoted, and the oil recovery rate is improved. Furthermore, although gas with a high carbon number is generated during normal thermal decomposition, thermal decomposition under high pressure promotes thermal decomposition reaction between the solvent and the dissolved and insoluble mixed waste plastics. The amount of transfer of the molecular organic material to the low molecular organic material is increased, and the oil having a relatively low carbon number content can be recovered.

The dissolution and pyrolysis gasification of the mixed waste plastics under a high pressure of 2 atm or more, preferably 5 atm of gauge pressure can accelerate the dissolution rate of the mixed waste plastics in the solvent, and This is for the purpose of achieving the effect of lightening by the reaction (hydrogenation) of the decomposition product hydrogen gas and other decomposition product gas. When the processing pressure for the dissolution or thermal decomposition gasification is less than 2 atm of the gauge pressure, the dissolution rate is promoted or lightened. This is because the effect of conversion becomes smaller.

Further, according to the mixed waste plastic processing apparatus of the present invention, the mixed waste plastic is dissolved while maintaining the pressure of the melting pyrolysis gasification means or the melting pyrolysis gasification means at a predetermined pressure of 2 atm or more in gauge pressure. Since plastic is melted or pyrolyzed and gasified, and the generated gas is continuously lightened and liquefied, mixed waste plastic can be stably transferred and processed continuously, and volume reduction and recycling are possible. Can be efficiently converted.

[0016]

EXAMPLES Examples of the present invention will be described below. [Embodiment 1] FIG. 1 is a schematic view of an apparatus for treating mixed waste plastic in a batch system, and FIG. 2 is a schematic view showing a pressure change in the melting pyrolysis furnace 2.

A mixed waste plastic containing a thermoplastic and a thermosetting plastic is crushed in advance and stored in a predetermined amount in the storage tank 1 through the inlet 31. In this embodiment, 230 g of glass fiber reinforced plastic (FRP), which is a thermosetting resin, and unsaturated polyester resin (U
P) to 130 g, epoxy resin (EP) to 230 g,
200 g of polystyrene (PS), which is a thermoplastic resin,
A mixed waste plastic obtained by mixing polypropylene (PP) at a ratio of 300 g was crushed to a size of 10 mm or less and supplied to the storage tank 1.

The ball valve 10 is opened by the controller 200,
After supplying a predetermined amount of mixed waste plastic from the storage tank 1 to the melting pyrolysis furnace 2, the ball valve 10 is closed. After that, the controller 200 opens the stop valves 14 and 15 and simultaneously activates the transfer pump 6 to supply a predetermined amount of the solvent from the oil storage tank 5 to the melting pyrolysis furnace 2. In this example, creosote oil was used as a solvent, and 200 g of creosote oil was supplied to 1090 g of the mixed waste plastic.

In the process in which the melting pyrolysis furnace 2 is heated to the pyrolysis temperature, the solvent having a low boiling point is gasified in the initial heating state, and the interior of the melting pyrolysis furnace 2 is mixed as the pressure is increased to the pyrolysis pressure. Part of the waste plastic is melted. Further, when the melting pyrolysis furnace 2 is heated to the pyrolysis temperature, the pyrolysis gasification of the solvent and the dissolved and insoluble mixed waste plastic is promoted. In this example, the thermal decomposition temperature of the melting thermal decomposition furnace 2 was set to 500 ° C., and the thermal decomposition pressure was set to a gauge pressure of 8 atm.

The pressure in the melting heating decomposition furnace 2 is the pressure detector 1.
Monitored by 01. When the pressure in the melting pyrolysis furnace 2 rises due to the pyrolysis gasification of the mixed waste plastic and exceeds 8 atm, the controller 200 opens the stop valve 12,
The pyrolysis gas is introduced into the catalyst lightening furnace 3. When the pyrolysis gas flows out and the pressure inside the furnace falls below the gauge pressure of 8 atm, the controller 200 closes the stop valve 12. Thus, during the thermal decomposition, as shown in FIG.
The internal pressure is maintained at about 8 atm, and the pyrolysis gasification of the solvent and the dissolved and insoluble mixed waste plastic is promoted.

The catalyst lightening furnace 3 lightens the pyrolysis gas by a catalytic reaction with a zeolite catalyst or a manganese catalyst heated to a predetermined temperature. The lightened gas is condensed and liquefied in the cooler 4, and the liquefied oil component is stored in the oil storage tank 5. A part of the liquefied oil component stored in the oil storage tank 5 is supplied to the melting pyrolysis furnace 2 as a solvent. At the end of pyrolysis gasification, the pressure in the furnace becomes constant and the pressure detector 1
The opening / closing operation of the stop valve 12 based on 01 detecting the pressure increase in the furnace is stopped. When the operation rest time of the stop valve 12 exceeds a set time, for example, 5 minutes, the stop valve 12 is opened to reduce the pressure in the furnace. Then, when the pressure inside the furnace is reduced to 6 atm of the gauge pressure, the stop valve 12 is closed, and after waiting for 5 minutes in that state, it is confirmed that the pressure inside the furnace does not rise, that is, the pyrolysis is completely completed, The stop valve 12 is opened again, and the furnace pressure is reduced to 0 gauge pressure, that is, atmospheric pressure.

When the pressure in the melting pyrolysis furnace 2 drops to atmospheric pressure, a predetermined amount of nitrogen gas is supplied from the bottom of the melting pyrolysis furnace 2 by means not shown to remove the residual pyrolysis gas in the melting pyrolysis furnace 2. It is discharged and introduced into the catalyst lightening furnace 3. After the discharge of the residual pyrolysis gas is completed, the stop valve 12 is closed, and then the ball valve 11 is opened to discharge the undecomposed mixed waste plastic (residue) to the outside of the system. Next, the ball valve 10 is opened again, the mixed waste plastic previously stored in the storage tank 1 is supplied to the melting and pyrolysis furnace 2, and the above operation is repeated. In this embodiment, the residual ratio is 24.0 W based on the weight of the thermosetting resin treated in the mixed waste plastic.
t%, and the decomposition gasification rate was 76.0 Wt% (the breakdown is 32.2 Wt of exhaust gas and 43.8 Wt% of oil recovery).

Comparative Example 1 230 g of glass fiber reinforced plastic (FRP), unsaturated polyester resin (U
130 g of P) and 230 g of epoxy resin (EP) were mixed, and waste plastic was supplied to the storage tank 1. After that, the mixed waste plastic was supplied to the melting pyrolysis furnace 2 in the same manner as in the above-mentioned example, and the thermosetting resin alone was used for pyrolysis. Pyrolysis was carried out for 1 hour while raising the temperature in the furnace from room temperature to 500 ° C. and maintaining it at 500 ° C. and maintaining the pressure in the furnace at a gauge pressure of 8 atm. As a result, the residual ratio of 5 to the processing weight of mixed waste plastic consisting of only thermosetting resin
3.1 wt%, decomposition gasification rate 46.9 wt% (The breakdown is exhaust gas 21.7 wt%, oil recovery rate 25.2 wt%)
Became.

[Comparative Example 2] Further, in order to examine how much organic matter was contained in the sample of Comparative Example 1, glass fiber reinforced plastic (FRP) was prepared so that the treatment weight ratio was the same as that of Comparative Example 1. ) 0.023 g, unsaturated polyester resin (UP) 0.013 g and epoxy resin (E
P) 0.023 g was mixed to prepare a mixed waste plastic sample. This sample was heated from room temperature to 500 ° C. in a nitrogen atmosphere using a differential thermal balance, maintained at 500 ° C., and the weight loss rate after 1 hour was measured.

As a result, the weight reduction rate with respect to the treated weight of the mixed waste plastic was 79.3 Wt% (gasification rate, gasification amount of organic matter), and the residue rate was 20.7 Wt% (weight of inorganic matter). It can be seen that the content is 79.3 Wt%. Under these conditions, the pyrolysis gas was further cooled and liquefied to recover an oily component. The result of Comparative Example 2 is that, in the thermosetting resin single type, the residual rate is 20.7 Wt% (inorganic content weight), and the content of the remaining organic matter is 79.3 Wt%. In an ideal case, It is shown that this organic mass can be completely gasified. On the other hand, in the thermal decomposition treatment with the single thermosetting resin of Comparative Example 1, the residual rate was 53.1 W.
t%. This is because in the thermal decomposition treatment in Comparative Example 1, the organic component in the thermosetting resin was about 2.57 as compared with Comparative Example 2.
It remains twice as much without being gasified, indicating that the gasification rate is low and only a small amount of oil can be recovered.

On the other hand, in the thermal decomposition treatment in Example 1, the residual rate and the thermal decomposition gasification rate were also the same as the results in the differential thermal balance of Comparative Example 2, and compared with Comparative Example 1, the thermosetting resin content was It can be seen that the oil recovery rate has also increased about twice. On the other hand, as a result of examining the carbon number of the recovered oil composition by gas chromatography mass spectrometry (GC / MS), in Comparative Examples 1 and 2, components having 20 or more carbon atoms accounted for about 60 Wt% of the whole. On the other hand, in Example 1, it was found that the component having a carbon number of 20 or more was about 40 Wt% of the whole, and the lightening amount was increased by 20 Wt% as compared with Comparative Examples 1 and 2.

As described above, a part of the mixed waste plastic is dissolved by mixing the solvent and the mixed waste plastic and thermally decomposing and dissolving under high pressure, and the solution becomes a heat medium or a reaction medium. The pyrolysis gasification of the organic resin component of the thermosetting plastic, which is difficult to gasify by independent pyrolysis, is promoted, and the oil recovery rate can be improved. Furthermore, although gas with a high high carbon content is generated during normal pyrolysis,
Due to the thermal decomposition under high pressure, the thermal decomposition reaction between the solvent and the dissolved and insoluble mixed waste plastics can be promoted, and the gasification reaction that increases the transfer amount of high molecular weight organic compounds to low molecular weight organic substances is performed. It can be seen that the oil having a relatively low carbon number content can be recovered and the oil recovery rate can be increased.

[Embodiment 2] FIG. 3 is a schematic view of an apparatus for continuously treating mixed waste plastics. In FIG. 3, components different from those of the batch type processing apparatus of FIG. 1 are the melting furnace 7, the ball valve 16, the stop valve 17, and the pressure detector 10.
3, the controller 201. A predetermined amount of the mixed waste plastic is stored in the storage tank 1 from the inlet 31. Also in this example, as in the case of Example 1, the thermoplastic resin was 230 g of glass fiber reinforced plastic (FRP), 130 g of unsaturated polyester resin (UP), and 230 g of epoxy resin (EP), which were thermosetting resins. 200 g of resin polystyrene (PS) and 3 of polypropylene (PP)
10 mm of mixed waste plastic mixed at a rate of 00 g
It was crushed into the following sizes and supplied to the storage tank 1.

First, the ball valve 10 is opened by the controller 201, the mixed waste plastic is supplied from the storage tank 1 to the melting furnace 7, and then the ball valve 10 is closed. Further, in response to the signal from the controller 200, the stop valves 14 and 15 are opened, the transfer pump 6 is operated, and a predetermined amount of the solvent is supplied to the melting furnace 7. Creosote oil was used as the solvent, and the addition amount was 200
The ratio was g.

In the process of heating the melting furnace 7 to the melting temperature, in the initial heating state, the low boiling point solvent is evaporated and the melting furnace 7 is pressurized to the melting pressure and at the same time a part of the mixed waste plastic is melted. It In this example, the temperature of the melting furnace 7 was set to 300 ° C. and the pressure was set to a gauge pressure of 8 atm. The pressure in the melting furnace 7 is monitored by the pressure detector 103, and when the pressure in the melting furnace 7 exceeds a gauge pressure of 8 atm in the melting process, the stop valve 17 is controlled by the controller 200.
Is opened, and the stop valve is closed again when the pressure in the furnace is lowered, so that the pressure in the melting furnace 7 is maintained at about 8 atm.

The solvent and the pyrolysis gas that have passed through the stop valve 17 are introduced into the catalyst lightening furnace 3. The catalyst lightening furnace 3
The catalytic reaction with a zeolite-based catalyst or manganese-based catalyst heated to a predetermined temperature lightens the solvent and pyrolysis gas. The lightening gas is condensed and liquefied in the cooler 4,
The liquefied oil component is stored in the oil storage tank 5. Next, the controller 201 controls the pressure detector 1 after a preset time elapses.
When it is confirmed by 03 that the pressure in the melting furnace 7 does not exceed the gauge pressure of 8 atm, the ball valve 16 is opened to dissolve the remaining solvent and the dissolved and undissolved mixed waste plastic from the melting furnace 7 without gasifying and discharging. Transfer and supply to the pyrolysis furnace 2. The temperature of the melting pyrolysis furnace 2 is set to 500 ° C., and the pressure is set to a gauge pressure of 8 atm.

In the melting and pyrolysis furnace 2, the solvent and the melted and undissolved mixed waste plastic transferred and supplied are pyrolyzed and gasified in the same manner as in the first embodiment. During the process in which the melting pyrolysis furnace 2 is heated to the pyrolysis temperature, the solvent with a low boiling point is evaporated in the initial heating state, and one of the mixed waste plastics is heated as the interior of the melting pyrolysis furnace 2 is pressurized to the pyrolysis pressure. Parts are dissolved.

The pressure in the melting heating decomposition furnace 2 is the pressure detector 1.
Monitored by 01. When the pressure in the melting pyrolysis furnace 2 rises due to the pyrolysis gasification of the mixed waste plastic, and the gauge pressure exceeds 8 atm, the controller 200 causes the stop valve 12
Is opened and the pyrolysis gas is introduced into the catalyst lightening furnace 3. When the pyrolysis gas flows out and the pressure inside the furnace falls below the gauge pressure of 8 atm, the controller 200 closes the stop valve 12. Thus, during the thermal decomposition, as shown in FIG. 2, the pressure in the melting thermal decomposition furnace 2 is maintained at about 8 atm gauge pressure, and the thermal decomposition gasification of the solvent and the dissolved and insoluble mixed waste plastic is promoted. It

At the end of pyrolysis gasification, the pressure in the melting pyrolysis furnace 2 becomes constant, and the opening / closing operation of the stop valve 12 based on the pressure detected by the pressure detector 101 is stopped.
The controller 200 opens the stop valve 12 when the operation stop time of the stop valve 12 exceeds 5 minutes, and reduces the pressure inside the furnace to a gauge pressure of 6 atm. After waiting for 5 minutes in that state, and confirming that the furnace pressure does not rise, that is, the pyrolysis is completely completed, the stop valve 12 is opened again to lower the furnace pressure to the atmospheric pressure.

When the inside of the melting pyrolysis furnace 2 is lowered to the atmospheric pressure, a predetermined amount of nitrogen gas is supplied from the bottom of the melting pyrolysis furnace 2 by means not shown to remove the residual pyrolysis gas in the melting pyrolysis furnace 2. It is discharged and introduced into the catalyst lightening furnace 3.
After exhausting the residual pyrolysis gas, stop valve 12
Is closed, and then the ball valve 11 is opened to discharge the undecomposed mixed waste plastic (residue) to the outside of the system. At this point, the mixed waste plastic stored in advance in the storage tank 1 is supplied to the melting furnace 7 by opening the ball valve 10, and the above operation is repeated to continuously pyrolyze the mixed waste plastic.

Also in this example, the decomposition gasification rate was 7 with respect to the weight of the thermosetting resin treated in the mixed waste plastic.
6.0 Wt% (The breakdown is exhaust gas 32.2 Wt%, oil recovery rate 43.8 Wt%) and the residue rate is 24.0 Wt%
Became. As described above, even in the continuous treatment method, the solvent and the mixed waste plastic are mixed, and a part of the mixed waste plastic is dissolved by thermally decomposing and dissolving under a high pressure, so that a relatively low carbon number is contained. It can be seen that a large amount of oil can be recovered and the oil recovery rate can be increased.

[0037]

EFFECTS OF THE INVENTION According to the present invention, the thermosetting resin and the thermoplastic resin are relatively hard to be pyrolyzed and gasified by the treatment while the thermosetting resin and the thermoplastic resin are mixed without removing the thermosetting resin waste from the waste plastic. The decomposition rate of the thermosetting resin can be increased, oil with a relatively low carbon content can be recovered, and
The oil recovery rate can be increased.

[Brief description of drawings]

FIG. 1 is a schematic view of a batch type mixed waste plastic processing device.

FIG. 2 is a schematic diagram showing the pressure in a melting pyrolysis furnace.

FIG. 3 is a schematic diagram of a continuous waste plastic processing device.

[Explanation of symbols]

1 ... Storage tank, 2 ... Melting / pyrolysis furnace, 3 ... Catalyst lightening furnace, 4
... Cooler, 5 ... Oil storage tank, 6 ... Transfer pump, 7 ... Melting furnace, 10, 11, 16 ... Ball valve, 12, 14, 15,
17 ... Stop valve, 101, 103 ... Pressure detector, 20
0,201 ... Controller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Miyadera 1-1-1, Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory

Claims (8)

[Claims] 1. A mixed waste plastic of a thermosetting resin and a thermoplastic resin is mixed with a solvent in a closed container, the solvent is gasified by heating to increase the pressure, and the mixed waste plastic is mixed under the increased pressure. A method for treating mixed waste plastics, characterized in that the waste plastics are dissolved and the dissolved and insoluble mixed waste plastics are pyrolyzed and gasified. 2. The mixed waste plastic according to claim 1, wherein the mixed waste plastic is dissolved under a pressure of 2 atm or more of a gauge pressure, and the solvent and the dissolved and insoluble mixed waste plastic are pyrolyzed and gasified. Processing method. 3. A mixed waste plastic of a thermosetting resin and a thermoplastic resin is mixed with a solvent in a first closed container, and the solvent is gasified by heating to increase the pressure in the first closed container. The mixed waste plastic is dissolved in the first closed container maintained at a predetermined pressure, and then the solvent and the dissolved and insoluble mixed waste plastic in the first closed container are mixed with the second closed plastic.
The second closed container by transferring to a closed container of No. 2 and heating the solvent and the dissolved and insoluble mixed waste plastic in the second closed container, and gasifying the solvent and heating decomposition of the dissolved and insoluble mixed waste plastic gasification A method for treating mixed waste plastics, characterized by increasing the internal pressure and pyrolyzing and gasifying the solvent and the dissolved and insoluble mixed waste plastics in the second closed container maintained at a predetermined pressure. 4. The pressure in the first closed container is maintained at a gauge pressure of 2 atm or higher, the mixed waste plastic is melted under the pressure, and the pressure in the second closed container is maintained at a gauge pressure of 2 atm or higher. 4. The method for treating mixed waste plastics according to claim 3, wherein the solvent and the dissolved and insoluble mixed waste plastics are pyrolyzed and gasified under the pressure. 5. A storage means for storing a waste plastic mixture of a thermosetting resin and a thermoplastic resin, and a dissolution pyrolysis gasification means for the mixed waste plastic connected to the storage means.
Solvent storage means, means for supplying a solvent from the solvent storage means to the dissolution pyrolysis gasification means, means for maintaining the inside of the dissolution pyrolysis gasification means at a predetermined temperature, and inside the dissolution pyrolysis gasification means Pressure maintaining means for maintaining the pressure of 2 to a predetermined pressure of 2 atm or more of gauge pressure, a lightening means for lightening the gas discharged from the melt pyrolysis gasification means, and a gas lightened by the lightening means An apparatus for treating mixed waste plastics, comprising: a means for cooling and liquefying the liquefied material; a means for storing the liquefied material; and a means for discharging undecomposed matter in the melt pyrolysis gasification means. 6. The pressure maintaining means includes a pressure detecting means for detecting a pressure in the melt pyrolysis gasification means, and a valve means provided between the melt pyrolysis gasification means and the lightening means. 6. The treatment apparatus for mixed waste plastics according to claim 5, further comprising control means for controlling opening / closing of the valve means based on a detection signal from the pressure detection means. 7. A storage means for storing a waste plastic mixture of a thermosetting resin and a thermoplastic resin, a dissolving means for the waste plastic mixture connected to the storage means, a solvent storage means, and a solvent storage means. Means for supplying a solvent to the dissolving means, means for maintaining the inside of the dissolving means at a first predetermined temperature, and first pressure maintaining means for maintaining the pressure inside the dissolving means at a predetermined pressure of 2 atm or more. A means for melting and pyrolyzing gasification of mixed waste plastics connected to the melting means,
A means for maintaining the inside of the melt pyrolysis gasification means at a second predetermined temperature equal to or higher than the first temperature; and a means for maintaining the pressure within the melt pyrolysis gasification means at a predetermined pressure of a gauge pressure of 2 atm or more. 2, pressure maintaining means, lightening means for lightening the gas discharged from the melting means and melt pyrolysis gasification means, means for cooling and liquefying the gas lightened by the lightening means, An apparatus for treating mixed waste plastic, comprising: a means for storing a liquefied material and a means for discharging an undecomposed material in the melting pyrolysis gasification means. 8. The first pressure maintaining means comprises first pressure detecting means for detecting a pressure in the dissolving means, valve means provided between the dissolving means and the lightening means, and the first pressure detecting means. A control means for controlling the opening and closing of the valve means based on a detection signal from the first pressure detection means, and the second pressure maintaining means detects a pressure in the dissolving means; A valve means provided between the dissolving means and the lightening means, and a control means for controlling opening / closing of the valve means based on a detection signal from the second pressure detecting means. Item 7. A mixed waste plastic processing device according to item 7.