JP2757730B2 - How to reuse polyester / metal laminate - 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 recycling polyester / metal laminate waste, and more particularly, to a method for recycling polyester / metal laminate waste.
Heat the metal laminate waste on which the polyester film and the like are laminated in the presence of the polyolefin resin, decompose the polyester of the laminate together with the polyolefin and collect it as oil and gas, and keep the metal sheet in a substantially clean state. The present invention relates to a method for recycling polyester metal laminate waste material or waste, which is characterized by being recovered.

[0002]

2. Description of the Related Art In recent years, the reuse of waste materials or wastes such as metals, plastics, or laminates of metals and plastics used in packaging containers and the like is related to the treatment of municipal waste or industrial waste. It is becoming an important issue.

For this reason, various recycling systems have already been established and newly implemented from the viewpoints of waste disposal and resource saving with respect to the reuse of waste materials and wastes of the packaging containers and the like. A proposal has been made.

[0004] For example, in the case of waste material or waste of a container substantially made of a metal material, specifically, in the case of using steel, aluminum, or the like, they are sorted out for each type of metal.
After appropriate treatment, techniques and systems for recycling and reusing these as container materials or other product materials have already been established and implemented.

[0005] Further, in the case of containers made of substantially plastic, for example, these waste materials or wastes are sorted or treated and added to a part of raw material plastic or reused as another recycled plastic product. In some cases, a method has been proposed in which waste plastics are decomposed by thermal decomposition or the like and reused in the form of cracked oil or cracked gas, and some methods have been implemented. .

However, recently, with the diversification of needs for packaging containers, so-called composite materials using a combination of metal and plastic, and other materials, for example, polyolefin, polyester, and other laminated materials of plastic and metal, etc. Has been produced and used as a material for packaging containers.

[0007] When reusing waste materials or wastes of containers made of these composite materials, it is often necessary to separate and sort each component member of the composite material for reuse.
In most cases, it was not practical either from an economic point of view or from a throughput point of view.

[0008] For example, even if only the metal material is recycled from the laminated material of plastic and metal and the plastic is incinerated or otherwise treated, the surface of the metal material after incineration is completely burned out. Resin residue, carbon, etc. that did not exist, or inorganic fillers added to plastics, such as non-flammable components such as metal oxide powder, adhered a lot and deteriorated the quality of the recycled metal as it was, Since the quality of the metal is not sufficient, or extra steps such as separation of unnecessary unnecessary residues and the like by washing or other methods are required, many disadvantages are caused economically and in the processing steps. In fact, the fact is that a sufficient regeneration method has not been established.

In particular, recently, in the field of food, such as beverage filling cans, a large number of laminated materials in which a polyester resin layer such as polyethylene terephthalate is laminated on a metal plate layer have been produced and used. When recycling and recycling scraps, waste materials, and wastes of used products generated during the manufacture of products such as containers from materials, it is not always easy to completely separate the laminated polyester and metal from the materials. However, even if the polyester layer of the material is incinerated and removed to recover only the metal material, dibasic acid components such as terephthalic acid, which is a depolymerized decomposition product of polyester partially decomposed during incineration, and fragments thereof Causes sublimation and deposition in the incinerator, which makes it more difficult to regenerate than the other ordinary laminates described above. There was.

[0010]

SUMMARY OF THE INVENTION The inventors of the present invention collect scrap and waste materials such as laminated materials of polyester and metal which are generated in large quantities in a laminated material production plant or a processing and molding plant and recycle them. As a result of various studies and researches on the method of utilizing, the waste material of the laminated body of the polyester and the metal sheet was allowed to coexist with a specific amount or more of the polyolefin with respect to the polyester resin component of the waste material, and the waste material and the polyolefin resin were mixed. Is heated to a temperature equal to or higher than a specific temperature to thermally decompose the resin component, and then thermally decompose the resulting pyrolyzate at a relatively low temperature compared with the case where it is treated by a conventional decomposition method. Not only can cracked oil or cracked gas be obtained at a very high cracking or reforming rate with good yield, but also the metal sheet in the waste material can be substantially cleaned, that is, the recovered metal sheet can be recovered. Or no resin component residue, carbon, decomposed matter, etc. adhere to the surface of the metal sheet, or even if some adherent matter remains, the adhered matter is easily peeled off or separated from the metal sheet surface. The inventors have found that the present invention has been completed.

[0011]

According to the present invention, a waste of a laminate of a polyester film and a metal sheet is heated to a temperature higher than the melting temperature of the polyester in the coexistence of a polyolefin resin at a weight of 10 times or more per polyester. Heat to temperature, pyrolyze polyester and polyolefin,
A method for recycling a polyester metal laminate is provided, wherein the generated pyrolyzate is then subjected to catalytic cracking to recover gas or oil, and the metal sheet is recovered in a substantially clean state.

[0012]

According to the present invention, waste materials or wastes of a laminate of a polyester film and a metal sheet are put into a pyrolysis tank or a pyrolysis pot, and heated to a temperature not lower than the melting point of the polyester resin to form a polyester resin component or the like. When the resin component in the waste material is thermally decomposed, a polyolefin-based resin is used in an amount of at least 10 times the weight of the polyester resin present in the waste material at the time of thermal decomposition, and the resin component is thermally decomposed in the coexistence. The point is the biggest feature.

[0013] A polyolefin resin having a specific compounding ratio or more is added to the waste material of the laminate of the polyester film and the metal sheet, and the waste material is heated in the presence of the polyolefin resin to melt the resin component and thermally decompose. It is possible to obtain cracked oil or cracked gas at a relatively low temperature and at a remarkably fast cracking rate with a high yield as compared with the case where thermal cracking is performed using only polyester film / metal sheet laminate waste material. In addition, it is possible to minimize the trouble of the decomposition apparatus or equipment due to the sublimation and adhesion of aromatic organic acid components or acid component residues such as terephthalic acid or terephthalic acid decomposition products generated during the thermal decomposition of the polyester resin in the waste material. Is suppressed.

Surprisingly, the surface of the metal sheet remaining after the thermal decomposition treatment is remarkably clean as compared with the case where the metal sheet is treated by another method, and the laminated resin such as polyester, polyester decomposition product or carbide is used. Hardly adheres, or even if it adheres slightly,
The deposit is obtained in a small amount and in a state where it is easily peeled or separated from the surface of the metal sheet.

The method of the present invention has been made based on a phenomenon that was accidentally discovered in the course of actual research and testing, and it has not been completely determined by what mechanism the above-mentioned effects are achieved. Although it has not been elucidated, probably, first, a relatively low-viscosity polyolefin-based resin decomposition melt that has been melted first is successively formed from the surface of the polyester resin layer softened or melted by increasing the temperature, and the polyester resin layer and the metal sheet layer It is presumed that it penetrates or permeates up to the interface of, and exhibits some action of weakening the adhesive force at the interface.

In particular, when the polyester resin is made of polyethylene terephthalate or the like, a binder resin layer is often interposed between the two layers in order to enhance the adhesiveness to the metal sheet layer. It is also conceivable that they may penetrate into the binder layer to significantly lower the adhesive strength.

Further, when heat is applied to the polyolefin resin, radicals are easily generated due to hydrogen abstraction in the hydrocarbon molecular chain, etc., and the resin molecular chain itself is cut to be decomposed into a relatively low-molecular-weight hydrocarbon. The removed hydrogen atoms and the like successively attack another molecular chain to promote thermal decomposition.

In this case, a large number of hydrocarbon fragments containing active radicals are generated in the hydrocarbon fragments generated by the thermal decomposition, and the hydrocarbon fragments come into contact with the polyester resin layer already melted or softened by heat. It is thought that the compound acts to infiltrate into the inside of the polyester to attack the molecular chain of the polyester, particularly the ester bond portion and the saturated hydrocarbon chain portion in the molecular chain, thereby promoting and promoting the cleavage and decomposition of the molecule.

In the present invention, a mixed vapor of a decomposition product of the resin component generated by the thermal decomposition in the thermal decomposition tank is further led to a catalytic cracking tank, and the mixed vapor is decomposed or reformed by a catalytic reaction.

Through such a catalytic reaction step, the cracked steam component generated in the thermal cracking step is reformed, the yield of cracked oil component or gas component is increased, and a cracked oil of higher utility value is obtained. Can be.

In the present invention, as described above, in many cases, the waste metal sheet recovered after the completion of the thermal decomposition treatment of the resin component can be reused as a metal material for regeneration in many cases, but it is further washed. It is more preferable to perform other simple treatments to completely remove deposits on the metal surface before recycle.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The features of the present invention will be described in more detail based on specific embodiments.

FIG. 1 is a schematic diagram showing an example of a processing apparatus for performing the method of the present invention. In the example of this figure, a scrap of a laminated body composed of a metal sheet on which a polyester film is laminated, a used container discarded or a laminated material recovered as a defective product, or the like is cut into an appropriate size as required, or Pyrolysis tank 1 from input port (hopper 2)
Put in. Next, similarly, a polyolefin resin such as polyethylene or polypropylene is added at least 10 times, usually 10 to 10,000 times, preferably 20 to 70 times the weight of the polyester resin component such as the above-mentioned input laminate scrap.
Feed in a range of 00 times.

Of course, in the present invention, it is possible to mix a predetermined amount of granular, powdery or other polyolefin resin in advance with the above-mentioned laminate waste material and simultaneously charge them, or to charge only the polyolefin in advance. It is possible to add only a polyolefin in advance, raise the temperature to a molten state, and then add a polyester laminate scrap or the like.

In any case, after the introduction of the raw materials, the thermal decomposition tank is heated and heated to melt and thermally decompose the polyester resin and the polyolefin resin component.

The pyrolysis temperature varies slightly depending on the type of polyolefin charged and the type of polyester in the waste material and other aspects, but is usually at a temperature of 230 ° C to 700 ° C, preferably 250 ° C to 650 ° C. Pyrolysis is
The process is continued until the resin component is substantially completely decomposed.

The steam of the resin cracked product fraction flows out of a steam distillation outlet 9 provided at the upper part of the thermal cracking tank 1, and flows out of the catalytic cracking reformer 8
Will be introduced. In the catalytic cracking reformer 8, a metal plate such as nickel, aluminum, palladium, platinum or the like, or a catalyst plate 13 in the form of a mesh plate or a pore plate coated with such a metal is used as a catalyst for contact and reforming. A large number of gaseous fractions formed by the above-mentioned thermal decomposition are brought into contact with the metal of the contact catalyst plate, and are decomposed, reformed or partially recombined to be dimerized, The oil is reformed into a form useful as an oil. The reaction temperature of the catalytic reforming is usually from 250 to 650 ° C, preferably from 250 to 600 ° C.

In the present invention, the use of an ordinary porous supported catalyst-packed layer as the contact catalyst layer means that a substance having a relatively high melting point and a sublimation-extrudable substance such as terephthalate in the pyrolysis oil fraction is used. It is not preferable because of the clogging of the catalyst pores due to the inclusion of an acid or isophthalic acid or a decomposition product thereof, and it is preferable to use the above-mentioned plate-type packed layer such as a metal mesh or a perforated plate.

In the porous plate for a contact catalyst or the metal mesh plate used in the present invention, the pore size of the porous plate or the size of the mesh of the metal mesh plate is not necessarily critical, but is usually about 100 μ to 40 mm, preferably about 100 μm to 40 mm. Is 5
It is preferable to use one having a size of about 00 μm to 30 mm.

In the present invention, although not necessarily limited to this, for example, a catalyst layer as illustrated in FIG. 2, that is, an aluminum porous plate or an aluminum plate provided in the upper and lower layers of the contact reactor in the middle section It is particularly preferable to use a catalyst layer of a type in which a large number of nickel porous plates or mesh plates are arranged at intervals with a mesh plate therebetween in terms of catalyst efficiency and dynamic pressure loss.

FIGS. 3 and 4 show an example of a perforated plate filled in the contact reactor as a catalyst in the present invention. The cracked oil fraction thus reformed in the intimate reactor is cooled by the cooler 14, separated into oil, water, and gas, and then collected, and stored, discarded, or used.

After the thermal decomposition reaction is substantially completed, the thermal decomposition reaction tank is cooled, and the metal layer pieces 5 remaining in the tank are recovered. The recovered metal piece is reused as it is as a metal material for recycling or, if necessary, is subjected to a simple washing treatment or the like to completely remove deposits on the metal surface before being used for recycling.

In the case of the thermal decomposition tank of the embodiment shown in FIG. 1, a mesh-like floor plate 3 is provided at the lower part of the tank.
Non-volatile powders such as fillers, pigments, other inorganic additives, and carbon residue contained in the resin component fall from the mesh and accumulate on the tank bottom.

In the present invention, the laminate waste of the polyester film and the metal sheet used as a raw material includes the laminate structure, shape, type of polyester resin, presence or absence of compounding additives such as fillers, type of metal, and the like. Any can be used.

It is not always necessary to form a laminate comprising only a polyester layer and a metal layer. Layers other than the polyester layer, for example, polyolefin, vinyl chloride, vinylidene chloride, vinyl acetate, ethylene / vinyl acetate copolymer, ethylene / vinyl alcohol A resin layer other than polyester such as a copolymer may be laminated together with the polyester resin layer and the metal layer. Further, the polyester resin may be a copolyester, or may be a blend with another resin or a polyester ether copolymer. Examples of these polyester resins include polyethylene terephthalate, polyethylene terephthalate / isophthalate, polyethylene terephthalate / adipate, polybutylene terephthalate, polybutylene terephthalate / isophthalate, polyethylene naphthalate, polyethylene naphthalate / terephthalate,
And blend resins thereof. The kind of metal constituting the metal layer of the laminate is not particularly limited as long as it has a higher melting point than at least the polyester resin.

Normally, a laminate of metal layers made of iron, aluminum, electrolytic chromic acid-treated steel sheet, tinplate, galvanized steel sheet, and other metals used as a metal layer of a laminated material such as a container should be used without any trouble. Can be.

However, depending on the use of the recovered metal for regeneration, the reclaimed metal is often required to have a certain level of quality and purity, and when the method of the present invention is carried out, the metal layer must be of the same type. It is preferable from the viewpoint of reuse of the recovered metal that a collection of laminated bodies of almost the same quality is treated each time.

A composition ratio of the polyester layer and the metal layer;
That is, there is no critical limitation on the weight ratio such as the weight ratio, and the volume ratio is arbitrary.However, the method of the present invention is intended to pyrolyze and recover the polyester resin layer. From the viewpoint of effectively utilizing the features of the method of the present invention, it is preferable that the amount of the polyester resin component is not less than a certain amount with respect to the amount of the metal layer. Weight 0.5
% To about 10.0% is preferably used.

As a laminate waste that can be particularly preferably treated by using the method of the present invention, talc (T)
ULC) can be used as a waste material of a laminate for a two-piece can material that is commercially available.

This laminated material uses a TFS material (thickness: 0.15 to 0.3 mm) made of a high-strength thin steel plate as a metal layer, and a transparent polyethylene terephthalate /
A layer of a biaxially stretched film (thickness: 15 to 50 μm) based on a polyethylene isophthalate copolymer and, if necessary, blended with another polyester-based resin or laminated with the resin film, It is a laminated material obtained by laminating layers (thickness: 10 to 50 μm) of the polyester film containing titanium oxide powder on the side, and a container such as a can made by processing this laminated material by stretch draw molding has high strength. , And lightweight, both positive pressure cans (for gaseous beverages) and negative pressure cans (for hot pack beverages),
Also, it has many characteristics such as being usable for other cans, and has a great many advantages in that it can achieve energy saving and pollution-free in the production process as compared with the conventional can-making process. It has.

However, with regard to the recovery and regeneration of waste materials such as the scraps of the laminated material, it is difficult to sufficiently separate the metal layer and the resin layer from the laminated waste material by the conventional recovery and recycling method. Powder of titanium white or the like is blended in the polyester on the outer side of the surface, and even if the resin layer is to be removed by incineration, the inorganic substance such as titanium white is stuck to the surface of the recovered metal piece after incineration, and is recovered. When a metal is used for recycling, there is a problem in that the quality of the recycled product is deteriorated and the disposal of waste materials is difficult.

In particular, when the above-mentioned recovered metal is used for regenerating, a metal residue or a large amount of metal such as titanium, tin, copper or the like attached to the recovered metal is used as it is, and the recovered metal is used as a raw material. When compounded as, the impurities such as tin, copper, and titanium are mixed into the steel product, and these contaminants are
In addition to hindering the ductility of the product steel, it also has a detrimental effect such as brittleness of the steel, so that the quality of the product steel deteriorates.

As will be apparent from the following examples, when the above-mentioned laminate waste is treated by the method of the present invention, not only can the cracked reformed oil be recovered from the resin component in good yield, but also the treated metal after pyrolysis can be recovered. The pieces have very little adhesion of the above-mentioned inorganic substances, resin residues, and decomposed carbon, and can be collected as clean metal pieces.

In the present invention, the polyolefin resin thermally decomposed together with the laminate of the polyester film and the metal sheet is not necessarily limited. For example, various kinds of polyethylene, ethylene-vinyl acetate copolymer, polypropylene, polybutene-1, A polymer of butenes such as polyisobutylene, a copolymer of atactic or isotactic polystyrene and olefins such as ethylene, propylene and butene, or a blend thereof;
Resins and elastomers such as polybutadiene, polyhexadiene and polyisoprene, or mixtures thereof can be used. Further, these polyolefin-based resins may contain a small amount of other resins such as polyamide, polyvinyl alcohol, polyvinyl acetate, and acrylic resin.

Further, the polyolefin resin does not necessarily have to be a newly produced resin, and scrap, regrind, film waste, binding band waste, and other waste plastics that have been used once and have undergone heat history can be used. .

Rather, in the method of the present invention, it is preferable that the polyolefin-based resin be thermally decomposed more easily than at least the polyester resin component in the presence of the polyester resin layer. It is more preferable to use waste plastic that has passed through.

Particularly preferred polyolefin resins in the present invention are polyethylene, ethylene / vinyl acetate copolymer, polypropylene or ethylene / propylene copolymer resins, and waste molded products such as waste regrinds and films thereof.

The amount of the polyolefin resin to be added is usually at least 10 times by weight, preferably from 20 to 7000 times by weight, based on the weight of the polyester resin component in the laminate.

If the amount of the polyolefin resin is less than the above ratio, the decomposition of the polyester resin component does not proceed sufficiently at a lower temperature, so that the metal pieces cannot be recovered with a sufficiently clean surface. Cracked oil yield also decreases,
The amount of solid residue such as carbon residue is increased, which is not preferable.
The shape of the polyolefin resin to be charged is not particularly limited as long as it can be charged into the pyrolysis tank, but a powder or a granular or a sheet or film cut into small pieces is preferable from the viewpoint of handling and melting uniformity.

[0050]

Example 1 As a raw material for regeneration treatment, (1) TF made of a high-strength thin steel sheet having a thickness of 0.26 mm
Thickness 2 on one side inside S (Tin Free Steel) sheet
A 5 μm transparent polyester film (polyethylene terephthalate / isophthalate copolymer biaxially stretched film, d = 1.38) and a 20 μm thick white polyester film (white pigment titanium white (TiO 2)
₂ ) An average of 1.5 cm × 2 scraps of the polyester resin film / metal sheet laminate to which each of
This was cut into a size of about a cm square, and 5 kg of this was used. (2) On the other hand, as a polyolefin resin, scrap (thickness: about 0.1 mm) of a low-density polyethylene (d = 0.922, melting point: 107 ° C.) film (used low-density polyethylene film layer for packing) is used. 50 kg cut into 1 cm square pieces were prepared.

First, 50 kg of the above-mentioned low-density polyethylene strip was charged from a hopper of a pyrolysis apparatus of the type shown in FIG. 1 and heated until the polyethylene was melted (about 150 ° C.) by a heating burner. Then, 5 kg of the above-mentioned laminate scrap (weight ratio of polyester resin in the scrap laminate to polyethylene: about 1: 260) was added thereto, and the mixture was further heated and heated while stirring slowly.

When the temperature of the pyrolysis tank reached about 340 ° C., distillation of the pyrolyzed decomposition component vapor started. When the temperature was further raised and the temperature of the thermal decomposition tank reached 450 ° C., the reaction temperature was kept constant and the thermal decomposition was continued.

The temperature of the catalytic reformer for the gas phase cracked oil was maintained at about 340 ° C. during that time. The cracked reformed oil fraction condensed through the cooler is collected in a container, and after separating the water, the capacity is measured, and its properties are subjected to a distillation test, a raw material analysis,
Items such as carbonyl value, hydrocarbon type, and gas chromatographic analysis were evaluated. The amount of cracked reformed oil collected is 4
It was 6.7 kg. Table 1 shows the evaluation results for each item of the cracked reformed oil. When the pyrolysis reaction was practically completed and the distillation components did not distill, the heating was stopped and the pyrolysis tank and the catalytic reformer were cooled to room temperature by cooling. In this experiment, the duration of the heating and holding at 450 ° C. was about 0.5 hour. Thereafter, the metal pieces remaining in the pyrolysis tank were taken out and collected. About this metal piece, the thickness of the residual polyester resin on the surface of the metal piece collected from the bottom part and the upper part in the tank was measured, and the surface appearance was visually inspected. Table 2 shows the results.

Further, the results of measuring the relative concentrations of carbon and iron in the thickness direction from the surface of the metal piece collected from the bottom of the furnace using a glow discharge mass spectrometer manufactured by VG (Vacuum Generate) were used. FIG. 5 shows the profile in the depth direction of the steel material. Table 3 shows the results of elemental analysis of this metal piece sample.

[0055]

Example 2 In Example 1, the thermal decomposition temperature was set to 300 ° C.
Except that the thermal decomposition time was changed to 1.0 hour, the same treatment as in Example 1 was carried out to recover the cracked reformed oil and the metal pieces, and these were evaluated by glow discharge mass spectrometry and elemental analysis of the metal pieces. Except for omitting, evaluation was performed in exactly the same manner as in Example 1.
The results are shown in Tables 1 and 2. The amount of cracked reformed oil collected was 33.1 kg. In Table 2, in the column of "Appearance of residual polyester resin layer" in the table, the appearance of Example 2 was "brown film-like" and "easy peeling" was the brownish brown color in the experiment at a thermal decomposition temperature of 300 ° C. Although there was a composite layer in which the film-like polyester remained, 10 of those test pieces were selected, and a 1.5 cm-width cellophane tape was cut into a 1.5 cm-wide, 2 cm-depth cut piece, and a depth of 1.5 cm. As a result of performing the peeling test, the inner and outer polyester layers and the intermediate metal layer were peeled at a strength of 10 g / 1.5 cm width or less. This result is expressed as “easy peeling”.

[0056]

[Comparative Example 1] The experiment using the polyester / metal laminate waste (1) alone (60 kg) described in Example 1 without adding (2) low-density polyethylene described in Example 1 was carried out.
The test was performed in accordance with the conditions described in Example 1. However, the polyester resin forming the inner and outer layers adhered to the metal body in a granular manner,
The film was not formed. Further, the collected amount of the dispersed reforming oil in the inner and outer layers was 0.01 kg or less, and various analyzes were impossible. Further, as a result of elemental analysis of the sample in this experiment, the ratio of the titanium element to 100 g of iron was about 4 g.

[0057]

Comparative Example 2 A crushed used PET bottle was used in place of (2) polyolefin resin waste in place of (1) polyester / metal laminate waste in Example 1 and the same mixing ratio and the same as in Example 1. Although the experiment was conducted under the conditions, especially in the transportation system such as pipes and the cooling system such as cooling tower, crystalline precipitates from the resin were large and clogged the transportation system such as pipes. Stopped in time.

[0058]

COMPARATIVE EXAMPLE 3 When the combination in Example 1 was changed only in the thermal cracking condition and the catalytic cracking condition from Example 1 (both conditions were set to 200 ° C.), the amount of collected oil was 1.7 kg. Yes, the rest was deposited on the bottom of the pyrolysis kettle together with additives. The state between the polyester and the metal was considered to be normal in appearance under such conditions. However, according to the method described in Example 2, a cellophane tape peel test was performed.
When carried out on 0 samples, the peel strength between the metal and polyester layers was 970 / 1.5 cm on average,
Peeling was also judged to be difficult in the process.

The following can be seen from the results of Examples 1 and 2 and Comparative Examples 1, 2, and 3. That is, in Examples 1 and 2, the recovered cracked oil not only has a high recovery rate, but also has the properties as shown in the evaluation results shown in Table 1, as shown in Table 1. As a matter of course, it has been found that the material having sufficient properties to use it can be sufficiently used for applications such as high octane gasoline by performing an appropriate treatment such as fractionation.

Further, as is clear from Table 2, the metal pieces recovered after the heat treatment recovered in Examples 1 and 2 have not only an extremely thin remaining adhered resin layer, but also the resin layer is extremely easy to peel off, and therefore, it is simple. It can be seen that by a simple operation, it can be recovered as a substantially clean metal piece.

Further, as shown in Table 3, the recovered metal pieces include titanium, copper, tin and the like, which are harmful impurity elements when the metal pieces are used as a recycled material for cans and other steel materials. It can be seen that the contents were suppressed to low concentrations. JJBosley et al. (1989 Ele
ctric Furnace Conference Proceedings), and the results in Table 3 fully satisfies the permissible limits for each of the target scraps.

On the other hand, Comparative Example 1 in which the polyolefin resin was not added, Comparative Example 2 in which a crushed polyester resin bottle was added in place of the polyolefin resin, and Comparative Example in which the thermal decomposition conditions were out of the scope of the present invention. 3 etc., is the yield of the recovered cracked oil extremely low (Comparative Example 1,
3) or not recovered at all (Comparative Example 2), and polyester resin adheres to the metal body in a granular manner on the recovered metal pieces (Comparative Example 1), and peeling is extremely difficult even if it is a layered adhesion layer It can be seen that both of these methods are difficult (Comparative Example 3), and none of them can achieve the desired effects of the present invention.

[0063]

[Table 1]

[0064]

[Table 2]  

[0065]

[Table 3]  Note: In the laminated scrap before treatment in Example 1,
The content of the metal element is based on 100 g of iron in the metal layer of the laminate.
The results were as follows. Titanium 0.005g Copper 0.025g Tin 0.005g Carbon 0.10g

[0066]

According to the method of the present invention, it is possible to easily treat a waste material of a laminated product of a polyester film and a metal sheet, which has had a problem in disposal because of the difficulty in the conventional recycling. At the same time, it is possible to recover high quality cracked and reformed oil and metal pieces that can be sufficiently used as a recycled metal material from the waste material in a clean state with a high yield.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of a processing apparatus for performing the method of the present invention.

FIG. 2 is a schematic diagram schematically showing the internal structure of a catalytic cracking reformer for a pyrolysis oil used in the method of the present invention.

FIG. 3 is a view showing an example of a metal plate-shaped catalyst filled in the catalytic cracking reformer of the present invention.

FIG. 4 is a diagram showing another example of a metal plate catalyst filled in the catalytic cracking reformer of the present invention.

FIG. 5 is a graph showing a profile in a thickness direction of a remaining polyester layer / steel material of a recovered metal piece treated by the method of the present invention. (The measurement method is based on glow discharge mass spectrometry.)

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Pyrolysis tank 2 Raw material input port (hopper) 3 Mesh floor plate 4 Melt 5 Stack scrap 6 Heating burner 7 Flue 8 Cracking reformer 9 Thermal crack component steam distillation outlet 10 Cracking reformer Hot air outlet for heating 11 Stirrer 12 Furnace for heating 13 Porous metal plate for contact catalyst (13a Ni plate, 13
b Al plate) 14 cooler 20 small hole 21 mesh

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B09B 3/00-5/00 B29B 17/00-17/02 C08J 11/12 C10G 1/10

Claims (7)

(57) [Claims] 1. A waste of a laminate of a polyester film and a metal sheet is heated to a temperature higher than a melting temperature of a polyester in the presence of a polyolefin resin at a weight of 10 times or more per polyester, and the polyester and the polyolefin are heated. A method of reusing a polyester metal laminate, comprising decomposing and forming a pyrolyzate, and then catalytically decomposing the resultant to recover gas or oil, and recovering the metal sheet in a substantially clean state. 2. The method according to claim 1, wherein the pyrolysis is performed at a temperature of 230 to 700 ° C. 3. The method according to claim 1, wherein said catalytic cracking is performed at a temperature of 250 to 650 ° C. 4. The method according to claim 1, wherein the catalytic cracking catalyst comprises a combination of a nickel metal or nickel-coated porous metal plate on the surface thereof and a metal aluminum or aluminum-coated aluminum metal plate on the surface thereof. 5. A waste product of a laminate of the polyester film and the metal sheet, wherein the metal sheet is made of tin-free steel having a high tensile strength, and a transparent polyester film is contained on one side of the metal sheet and titanium white powder is contained on the other side. The method according to claim 1, wherein the polyester film is a waste of a laminated polyester resin film laminate. 6. The method according to claim 1, wherein the polyolefin-based resin comprises at least one selected from a polyethylene resin, an ethylene / vinyl acetate copolymer resin, a polypropylene resin, and an ethylene / propylene copolymer resin. 7. The method according to claim 1, wherein the polyolefin-based resin is coexisted in an amount of 10 to 10,000 times the weight of the polyester resin component of the laminate.