US-12623263-B2 - Waste-plastic oil conversion device

US12623263B2US 12623263 B2US12623263 B2US 12623263B2US-12623263-B2

Abstract

A waste-plastic oil conversion device includes a primary decomposition tank that generates a decomposition gas by melting waste plastic; a secondary decomposition tank that generates a low boiling point decomposition gas by heating a liquefied component generated by condensing a high boiling point component out of the decomposition gas generated by the primary decomposition tank at a temperature lower than a temperature in the primary decomposition tank; a melting tank that melts a plastic material that forms a solar battery panel so as to separate the plastic material into the plastic material and a valuable material; and a first storage tank that condenses and stores the decomposition gas and the low boiling point decomposition gas therein. The melting tank is connected to the primary decomposition tank so as to introduce the decomposition gas into the melting tank.

Inventors

Kenichi WATAYA
Tomonori WATAYA
Hideaki Koda
Toshiyasu Koda

Assignees

AGRI CULTURE KARUIZAWA CO., LTD.
WATAYA SEISAKUSHO CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20211130
Priority Date: 20210830

Claims (11)

1 . A waste-plastic oil conversion device comprising: a primary decomposition tank that generates a first decomposition gas by melting waste plastic at a first temperature; a secondary decomposition tank that generates a second decomposition gas with boiling point lower than that of the first decomposition gas by heating a liquefied component generated by condensing a component with boiling point higher than that of other components out of the first decomposition gas generated by the primary decomposition tank at a second temperature lower than the first temperature; a melting tank that melts plastic materials contained in a solar battery panel so as to separate the plastic material into the plastic material and a residue left after all of the plastic materials contained in the solar battery panel are melted; and a first storage tank that condenses and stores the first decomposition gas and the second decomposition gas therein, wherein the melting tank is connected to at least one of the primary decomposition tank or the secondary decomposition tank, and is configured to introduce the first decomposition gas or the second decomposition gas into the melting tank.
2 . The waste-plastic oil conversion device according to claim 1 : further comprising a separation tower that is disposed between the primary decomposition tank and the secondary decomposition tank, the separation tower configured to separate the first decomposition gas generated by the primary decomposition tank into a third decomposition gas introduced into a secondary storage tank and the liquefied component introduced into the secondary decomposition tank.
3 . The waste-plastic oil conversion device according to claim 2 , wherein the secondary decomposition tank includes a meshed partition wall that separates an inside of the secondary decomposition tank into a region that is connected to the separation tower and a region that is connected to at least one of the first storage tank or the melting tank, and a catalyst is disposed on a bottom portion on a lower side than the partition wall and on an upper surface of the partition wall.
4 . The waste-plastic oil conversion device according to claim 2 , wherein the melting tank includes an injection unit capable of injecting a liquefied component stored in the secondary storage tank into an inside of the melting tank.
5 . The waste-plastic oil conversion device according to claim 1 , wherein the melting tank includes: a support plate capable of mounting the solar battery panel thereon; a door capable of sealing the melting tank, and being openable and closeable so as to allow insertion and taking out of the solar battery panel into and from the melting tank; and a heater for maintaining the melting tank at a predetermined temperature.
6 . The waste-plastic oil conversion device according to claim 5 , wherein the door has a double wall structure with two walls defining a space between the two walls, the melting tank includes a nitrogen gas supply unit that supplies a nitrogen gas into the space, and the space is maintained at a pressure higher than an atmospheric pressure by the nitrogen gas during an operation of the melting tank.
7 . The waste-plastic oil conversion device according to claim 6 , wherein the melting tank is configured to inject a cooled nitrogen gas into the melting tank from the nitrogen gas supply unit after an operation of the melting tank is finished.
8 . The waste-plastic oil conversion device according to claim 5 , wherein the support plate includes: a meshed support plate that separates the residue from the solar battery panel and a molten plastic material; and a lattice-like support plate capable of mounting the meshed support plate and the solar battery panel thereon and having a plurality of through holes.
9 . The waste-plastic oil conversion device according to claim 5 , wherein the support plate further includes a rack capable of arranging solar battery panels disposed adjacently to each other in a state where a gap is formed between the solar battery panels in an inside of the melting tank.
10 . The waste-plastic oil conversion device according to claim 5 , wherein the support plate is configured to mount the solar battery panel thereon, is configured to move in an inside of the melting tank, and is configured to move the residue of the solar battery panel to a position where the residue is recovered after thermal decomposition of the solar battery panel.
11 . The waste-plastic oil conversion device according to claim 1 , wherein the melting tank is configured to allow introducing of the waste plastic having a size that cannot be introduced to the first decomposition tank.

Description

RELATED APPLICATIONS The present application is a National Phase of International Application No. PCT/JP2021/043866 filed Nov. 30, 2021, which claims priority to Japanese Application No. 2021-140035 filed Aug. 30, 2021. TECHNICAL FIELD The present invention relates to a waste-plastic oil conversion device (a device for converting waste plastic into oil). BACKGROUND ART The treatment of waste plastic that contains plastic such as plastic products that are wasted after being used and plastic residues that are generated in a manufacturing process of plastic products has now become an environment task to be jointly solved world-widely. Further, recently, as a power generation system that does not emit carbon dioxide, a photovoltaic generation system has been rapidly becoming popular. However, in future, it is predicted that solar battery panels that have reached the duration time or solar battery panels or the like that are broken due to a hazard or the like will be generated in large quantity. Accordingly, the establishment of a treatment method which imparts a small environmental load to the solar battery panels has been urgently requested. From a viewpoint of the effective utilization of a resource, there has been proposed a waste-plastic oil conversion device that collects and reuses a liquefied component that is generated by condensing a decomposition gas generated at the time of heating and melting waste plastic in a decomposition tank, that is, an oil component. Such a waste-plastic oil conversion device includes: a decomposition tank that heats and decomposes waste plastic; a supply unit that supplies the waste plastic to the decomposition tank; an oil conversion treatment unit (for example, a condensing tank) that collects and condenses a decomposition gas generated in the decomposition tank (for example, see patent literature 1). On the other hand, in general, a solar battery panel is treated as a waste after an outer frame and glass are removed manually. In view of the above, as a method for treating the solar battery panel, there has been proposed a method of collecting valuable materials by chemically decomposing and removing a plastic material for holding solar battery cells or the like of the solar battery panel. This method of treating the solar battery panel is a method where an oxide semiconductor is brought into contact with a back sheet of the solar battery panel, and under the presence of oxygen, plastic materials such as the back sheet, a filler, a sealing material are decomposed and removed at a temperature at which an oxide semiconductor forms a true electric conductor region. Then, after the plastic materials are decomposed and removed, valuable materials such as inter connectors, the solar battery cells, the outer frame, glass and the like are collected (for example, see patent literature 2). In the description made hereinafter, assume that waste plastic includes the plastic materials such as the back sheet, the filler and the sealing material. CITATION LIST Patent Literature Patent Literature 1: JP-A-2005/200538Patent Literature 2: JP-A-2016/190177 SUMMARY OF INVENTION Technical Problem The waste-plastic oil conversion device described in the above-mentioned patent literature 1 can collect and reuse an oil component (generated oil) that is generated by condensing a decomposition gas that is generated by heating and melting waste plastic in the decomposition tank. However, to thermally decompose waste plastic in the decomposition tank, pretreatment such as crushing, washing and drying of a waste becomes necessary. Accordingly, the treatment in a state where the outer frame (frame), glass of the solar battery panel are held and the treatment of a large-sized article that cannot be crushed become difficult to perform. On the other hand, the treatment device of the solar battery panel described in patent literature 2 can decompose and remove plastic materials such as the back sheet, the filler, the sealing material that constitute the solar battery panel. However, a decomposition gas that is generated when the back sheet, the filler, the sealing material and the like are decomposed, is decomposed into water and carbon dioxide due to a reaction between the decomposition gas and oxygen, and water and carbon dioxide are discharged to the outside. That is, although the valuable materials such as the interconnectors, the solar battery cells, the outer frame, and the glass can be collected, it is impossible to collect a liquefied decomposition gas from the plastic materials such as the back sheet, the filler and the sealing material. Further, the waste-plastic oil conversion device and the treatment device of the solar battery panels described above differ from each other in a treatment method, a management temperature and a device configuration and hence, it is difficult to handle the waste-plastic oil device and the treatment device of the solar battery panel simply as one device. Further, in