JP2002003860A - Melting and oilifying apparatus for waste plastics - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a melting and oilfying apparatus for waste plastics, which can dissolve efficiently not only fractionated waste plastics but also waste plastics, that are hardly separated from their insoluble admixture and are contained in highly wet wastes such as urban refuses, to subject them to solid- liquid separation, and which can dehydrate, dechlorinate and increase in calorific value a combustible admixture to convert it into a fuel. SOLUTION: There is provided a melting and oilifying apparatus for waste plastics which oilifies waste plastics by melting, the apparatus comprising a dissolving vessel 7 that holds waste plastics and a solvent oil, a solvent oil heating device 19 that heats the solvent oil to be introduced into the dissolveing vessel 7 to dissolve the waste plastics, and a solid-liquid separation device 8 that separates an insoluble admixture from the solvent oil in which the waste plastics are dissolved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to waste plastics and waste plastics mixed with insoluble contaminants contained in wastes such as municipal waste (hereinafter referred to as "waste plastics"). While dissolving efficiently,
The present invention relates to a melting and oiling apparatus for waste plastics, which decomposes combustible insoluble contaminants by dehydrating / dechlorinating them and increasing the calorific value to convert them into fuel.

[0002]

2. Description of the Related Art In recent years, the Containers and Packaging Recycling Law has been enacted and enacted following the enactment of the Recycling Resource Utilization Act for the purpose of environmental protection and resource protection. I have. In such a situation,
In the incineration treatment of municipal garbage, the difficulty of separating waste plastics and the difficulty of burning due to a decrease in the calorific value of incinerated materials due to high humidity have become problems. Incineration of waste plastics, which cannot be recycled, not only generates harmful gases, but also causes environmental pollution due to the generation and scattering of highly toxic dioxins. There are many difficulties in the treatment and disposal of waste plastics, such as the narrowing of landfills.

[0003] On the other hand, a recycling technique for converting waste plastics into fuel oil by converting the waste plastics into fuel oil or re-distilling and refining to make industrial raw materials has come into the spotlight. This waste plastics melting and oiling device separates waste such as municipal waste into waste plastics and insoluble contaminants, and only the separated waste plastics are filled into a melting and digester and sealed. After that, the melting and digesting furnace is heated from the outside, the waste plastics filled inside are heated and melted and digested, and the generated cooking gas is guided to a cooler, cooled and liquefied to obtain cracked oil, so-called heating. Melting / pulping equipment is often used. In addition, although rare, the lower combustion heat of the fuel in the gasifier causes the upper deposited fuel to be thermally decomposed to obtain a flammable cracked gas. A self-combustion dry-distillation gasification type oil liquefaction apparatus in which combustible gas generated in a baking furnace is guided to a cooler to be cooled and liquefied to obtain cracked oil is also used.

[0004]

However, in the above-mentioned conventional melter / oiler, firstly, the wall surface of the melting and digesting furnace is heated from outside by a combustion flame such as a burner, so that the wall surface of the digester is Is overheated, causing charring to occur and stick to the liquid contact surface in the digester, and this deposit impedes the heat transfer to the wall, and the efficiency of melting and digestion deteriorates with the lapse of operation. There was a problem. Secondly, there is a problem that the wall surface of the melting and digesting vessel is overheated due to the heat retention effect due to the adhesion of the carbide, and the material constituting the cooking vessel is deteriorated.

Third, when insoluble contaminants are mixed, they insulate and insulate the walls of the melting and digesting furnace, causing the first and second problems described above. There was a problem that it could not be used as a raw material. Also,
When melting is performed for the purpose of weight reduction only, the melt is taken out of the melter and the contaminants contained in the melt are separated. Is high, so solid-liquid separation is difficult. In the worst case, waste plastics containing such insoluble contaminants may coagulate and stick to the solid-liquid separation device, causing damage to the device. There is a problem that cannot be used as a raw material.

[0006] Further, the self-combustion type dry distillation gasification combustion type liquefaction apparatus has a disadvantage that the yield of recovered product oil is low because a part of the raw material is burned and consumed.

The present invention has been made in view of the above problems of the conventional waste plastic oiling apparatus, and it is difficult to separate not only waste plastics but also waste plastics and insoluble contaminants. Waste plastics, such as those contained in high-moisture municipal waste, can be efficiently dissolved and separated into solids and liquids. It is intended to provide a molten plasticizer for waste plastics which can be converted to fuel.

[0008]

Means for Solving the Problems In order to achieve the above object, a molten plasticizer for waste plastics according to the present invention is a molten plasticizer for waste plastics, which is made by melting waste plastics. A dissolving tank containing waste plastics and solvent oil, a solvent oil heating device for heating the solvent oil in the dissolving tank to dissolve waste plastics, and an insoluble contaminant from the solvent oil in which the waste plastics are dissolved A solid-liquid separation device for separating an object.

In this apparatus for melting waste plastics, the waste plastics are dissolved in the solvent oil by heating the waste plastics through the solvent oil. The dissolution of the waste plastics can proceed efficiently without any phenomenon or heat transfer obstruction due to this scorching phenomenon. And
Solvent oil in which waste plastics are dissolved has low viscosity and good fluidity, and since the fluidity is maintained even when the temperature drops, separation and deoiling of insoluble contaminants in a solid-liquid separation device is required. Can be performed well. Furthermore, the separated insoluble contaminants are dechlorinated and dehydrated by the heated solvent oil, and are reformed by impregnation with the solvent oil in which the waste plastics are dissolved. It can be used as a fuel. Further, the solvent oil in which the separated waste plastics are dissolved can be used as a fuel oil as it is, and can be reused as an industrial raw material oil by further purifying it by distillation.

In this case, a system in which the solvent oil in the dissolving tank is circulated outside and heated may be used for the solvent oil heating device.

[0011] This makes it possible to more effectively prevent charring from sticking to the inner wall surface of the dissolving tank, and to dissolve waste plastics more efficiently.

Further, a combustion furnace for introducing gas generated when the waste plastics are melted, and a cooling device for cooling the gas discharged from the combustion furnace can be provided.

[0013] Thus, the organic gas generated when the waste plastics are dissolved is burned to oxidize and deodorize, and the chlorine gas contained in the gas is combined and combined with the steam which is condensed by the cooling device. Can be recovered as aqueous hydrochloric acid.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a waste plasticizer for melting and oiling waste plastics according to the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the apparatus for melt-oiling waste plastics according to the present invention. The melting and oiling apparatus of the present embodiment has a melting tank 7 for storing waste plastics and solvent oil.
By circulating the solvent oil in the dissolving tank 7 outside and heating it, a solvent oil heating device 19 for dissolving the waste plastics in the dissolving tank 7 and an insoluble sandwich from the solvent oil in which the waste plastics are dissolved. A solid-liquid separator 8 for separating miscellaneous substances.

As the solvent oil, vegetable oils such as edible oils, mineral oils such as mechanical lubricating oils, and oils which are liquid at normal temperature such as waste oils of these vegetable oils and mineral oils can be used. Then, the solvent oil is heated to 180 to 28 by a solvent oil heating device.
By heating to 0 ° C., for example, the waste plastics are dissolved in the solvent oil in 1 to 2 hours. The ratio of solvent oil to waste plastics contained in the dissolution tank 7 is 60 to 7
It is appropriate to control waste plastics to be 30 to 40% by weight or less with respect to 0% by weight. The waste plastics include, for example, polypropylene, polyethylene, polystyrene, polyester, and the like, which can be dissolved in a solvent oil to make oil.

That is, in the waste plastics melting and oiling apparatus of this embodiment, first, waste plastics are melted in the melting tank 7.
After the raw material introduction port 1 is closed, the solvent oil stored in the separately provided solvent oil storage tank 13 is transferred from the solvent oil supply port 2 to the dissolution tank 7 to fill the dissolution tank 7. In this case, the height of the solvent oil level in the dissolution tank 7 is controlled by driving or stopping the solvent oil transfer pump 14 based on a signal from the level detector 15 provided in the dissolution tank 7. The solvent oil may be preheated on the solvent oil storage tank 13 side.

The solvent oil in the dissolving tank 7 is taken out from the hot oil return port 4 provided in the dissolving tank 7, and after the foreign matter is removed by a filtering device 17 provided downstream of the hot oil return port 4, the solvent oil is further removed. The solvent is transferred to a solvent oil heating device 19 via a circulation pump 18 provided on the downstream side, heated and sent into the dissolving tank 7 from the hot oil feed port 5 provided in the dissolving tank 7. In this case, the solvent oil in the melting tank 7 is circulated through the melting tank 7, the filtering device 17, the circulation pump 18, the solvent oil heating device 19, and the circulation line of the melting tank 7 until the melting of the waste plastics is completed. .

The temperature of the solvent oil in the dissolving tank 7 is controlled by a signal detected by a temperature detection controller 16 provided in the dissolving tank 7 to control the heating state of the solvent oil in the solvent oil heating device 19. The temperature is kept at a preset value in the detection controller 16. As a heat source of the solvent oil heating device 19, any heat source such as combustion heat of fuel oil or fuel gas, electric heat, waste heat gas, and critical gas (supercritical fluid) can be used.

The waste plastics in the dissolving tank 7 are dissolved in the heated solvent oil to become a synthetic oil with the solvent oil. In this case, the waste plastics are heated through the solvent oil, In this embodiment, since the circulation heating method does not directly heat the wall surface of the melting tank 7, there is no scorching phenomenon on the inner wall surface of the melting tank 7 due to carbides and no heat transfer obstruction due to the scorching phenomenon, and the waste plastics can be efficiently dissolved. Progresses.

On the other hand, when the waste plastics are dissolved, chlorine and low-boiling substances are vaporized to become an organic gas, and the water in the insoluble contaminants is heated by a heated solvent oil, It evaporates to steam, and as a result, a mixed gas of organic gas and steam is generated. The mixed gas of the organic gas and the steam is taken out from the evaporative gas outlet 3 at the upper part of the dissolving tank 7, passes through the flashback prevention device 20 provided downstream of the evaporative gas outlet 3, and further downstream with the burner 22. To the combustion furnace 21. The mixed gas led to the combustion furnace 21 is burned at a high temperature of 800.degree.
It is deodorized. In this case, the temperature in the combustion furnace 21 is controlled by the signal detected by the temperature detection controller 23 provided at the outlet of the combustion furnace 21 to control the combustion of the burner 22, and the temperature in the temperature detection controller 23 is set in advance. Maintained at a temperature of.

Hydrochloric acid and chlorine gas contained in the mixed gas are converted into high-temperature chlorine gas by the heat of combustion in the combustion furnace 21.
It is mixed with the combustion exhaust gas and discharged from the combustion furnace 21. This exhaust gas is guided to a cooling device 24 on the downstream side of the combustion furnace 21 and is cooled and liquefied. The chlorine gas in the combustion exhaust gas is combined and combined with water vapor which is condensed by cooling, and is liquefied. Into hydrochloric acid. Further, the combustion exhaust gas containing carbon dioxide as a main component remains as a gas without being liquefied even when cooled.

The liquefied hydrochloric acid and the gas mainly composed of carbon dioxide gas are supplied to a brackish water separator 25 provided downstream of the cooling device 24.
The hydrochloric acid is separated into hydrochloric acid water and gas by the air, and the hydrochloric acid water is stored in a hydrochloric acid water storage tank 28, and the separated gas is discharged as harmless exhaust gas from the exhaust tower 27 via the exhaust fan 26 into the atmosphere. Is discharged.

On the other hand, when the dissolving of the waste plastics in the dissolving tank 7 is completed, the heating of the solvent oil and the circulation line are stopped, and the melt discharge valve 6 provided at the bottom of the dissolving tank 7 is opened.
Then, the solid-liquid separation device 8 downstream of the melt discharge valve 6
The dissolved material in which the synthetic oil in which the waste plastics are dissolved and the insoluble contaminants are mixed is transferred. The dissolved matter transferred to the solid-liquid separation device 8 is separated into synthetic oil and insoluble contaminants. The synthetic oil is filtered by a filtration device 9 downstream of the solid-liquid separation device 8 and then filtered. Is stored in a synthetic oil storage tank 11 via a pump 10 provided on the downstream side.

The insoluble contaminants separated and deoiled from the synthetic oil in the solid-liquid separation device are stored in a contaminant box 12 on the downstream side of the solid-liquid separation device 8. In this case, since the synthetic oil is synthesized from vegetable oil or mineral oil and waste plastics, it has low viscosity and good fluidity, and since the fluidity is maintained even when the temperature drops, Solid-liquid separator 8
Separation and deoiling of synthetic oils and insoluble contaminants can be performed satisfactorily. The solid-liquid separator 8 may be a centrifugal separator, a compression deoiler, or a vacuum deoiler.

The flammable insoluble contaminants separated by the solid-liquid separation device 8 are dechlorinated and dehydrated when the waste plastics are dissolved in the dissolving tank 7, and further impregnated with synthetic oil. As a result of reforming, the calorific value is high and there is no risk of generating harmful components even if burned as fuel,
Alternatively, it can be molded and used as a harmless and good fuel. Further, the separated and recovered synthetic oil can be used not only as a fuel oil as it is, but also can be reused as an industrial raw material oil by re-distillation and purification.

As described above, in the present embodiment, the solvent oil heating device 19
Is heated by circulating the solvent oil in the dissolving tank 7 outside, but the solvent oil heating device 19 may be configured to directly heat the dissolving tank 7.

[0028]

According to the molten plasticizer for waste plastics of the present invention, the waste plastics are dissolved in the solvent oil by heating the waste plastics through the solvent oil. There is no scorching phenomenon on the inner wall surface and no heat transfer obstruction due to this scoring phenomenon, so that the dissolution of waste plastics can proceed efficiently. The solvent oil in which the waste plastics are dissolved has low viscosity and good fluidity, and since the fluidity is maintained even when the temperature drops, the separation and removal of insoluble contaminants in the solid-liquid separation device is performed. Oil can be performed well. Furthermore, the separated insoluble contaminants are dechlorinated and dehydrated by the heated solvent oil, and are reformed by impregnation with the solvent oil in which the waste plastics are dissolved. It can be used as a fuel. Further, the solvent oil in which the separated waste plastics are dissolved can be used as a fuel oil as it is, and can be reused as an industrial raw material oil by further purifying it by distillation. And by this, not only the separated waste plastics but also the waste plastics which are difficult to separate from the waste plastics and the insoluble contaminants and are included in the waste such as the highly humid municipal garbage. To efficiently dissolve and separate solids and liquids, and to promote dehydration and dechlorination of combustible contaminants and increase the calorific value to promote efficient use of fuel and reuse of waste plastics. Can be.

Further, by using a solvent oil heating device which circulates the solvent oil of the dissolving tank outside and heats it, the charring on the inner wall surface of the dissolving tank by the carbide can be more effectively achieved. It is possible to prevent waste plastics from dissolving more efficiently.

Further, by providing a combustion furnace for introducing a gas generated when the waste plastics are melted, and a cooling device for cooling the gas discharged from the combustion furnace, the organic furnace generated when the waste plastics are melted is provided. In addition to burning and oxidizing and deodorizing the gas, chlorine gas contained in the gas is combined and combined with water vapor to be condensed by a cooling device, and can be recovered as hydrochloric acid water.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a molten plasticizer for waste plastics of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Raw material input port 2 Solvent oil supply port 3 Evaporation gas outlet 4 Hot oil return port 5 Hot oil feed port 6 Dissolved substance discharge valve 7 Dissolution tank 8 Solid-liquid separation device 9 Filtration device 10 Pump 11 Synthetic oil storage tank 12 Contamination box DESCRIPTION OF SYMBOLS 13 Solvent oil storage tank 14 Transfer pump 15 Level detector 16 Temperature detection controller 17 Filtration device 18 Circulation pump 19 Solvent oil heating device 20 Flashback prevention device 21 Combustion furnace 22 Burner 23 Temperature detection controller 24 Cooling device 25 Steam separator 26 exhaust fan 27 exhaust tower 28 hydrochloric acid water storage tank

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08J 11/20 B01D 53/34 134B F23G 5/00 ZAB B09B 3/00 ZAB 115 303E 7/12 ZAB F term (Reference) 3K061 AA18 AB02 AC13 BA06 DA01 DA17 4D002 AA19 AA40 AC10 BA02 BA05 BA13 DA35 EA05 4D004 AA07 AA46 AC04 BA03 CA13 CA29 CA47 CA48 CB04 CC04 4F301 AA13 AA14 AA15 AA25 CA09 CA12 CA24 CA05 4

Claims (3)

[Claims] 1. A waste plastics melting and oiling apparatus for converting waste plastics into oil by melting the waste plastics, comprising: a melting tank containing waste plastics and a solvent oil; and heating the solvent oil in the melting tank. -Oil melting of waste plastics, comprising: a solvent oil heating device for dissolving waste plastics by heating; and a solid-liquid separation device for separating insoluble contaminants from the solvent oil in which the waste plastics are dissolved. apparatus. 2. The molten plasticizer for waste plastics according to claim 1, wherein the solvent oil heater circulates the solvent oil in the dissolving tank externally to heat the solvent. 3. A combustion furnace for introducing gas generated when waste plastics are melted, and a cooling device for cooling gas discharged from the combustion furnace are provided.
Or a melting and oiling apparatus for waste plastics according to 2.