JPH11292976A - Treatment of plastic, and solid fuel and reducing agent for ore obtained by the treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for treating a plastic by which the treatment can be carried out even if films are mixed, a dehydrochlorination treatment can be simultaneously carried out, and a readily pulverizable plastic treated material can be obtained, and further to obtain a solid fuel and a reducing agent for an ore by the treating method, and to provide a method for blowing the plastic into a vertical type furnace by using the treating method. SOLUTION: This method for treating a plastic comprises forming the plastic into a mixed state with an organic solvent at >=150 deg.C to dissolve or swell the plastic, and removing the organic solvent or both of the organic solvent and a low boiling point component in the obtained treated liquid to solidify the plastic. The solid fuel and the reducing agent for an ore are the plastic material treated by the method. The method for blowing the plastic into a vertical furnace comprises blowing the plastic material treated by the treating method into a raceway of the vertical furnace for producing pig iron.

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 plastic which can obtain a plastic product which is extremely easy to pulverize. Further, the present invention relates to a method for treating plastic containing chlorine-containing plastics such as polyvinyl chloride. The present invention relates to a method for processing plastic that can be converted into a plastic containing no chlorine, a solid fuel obtained by the processing method, a reducing agent for ore, and a method for blowing plastic into a vertical furnace using the processing method.

[0002]

2. Description of the Related Art In recent years, as one solution for effective utilization of waste plastic, there is a method of producing solid fuel from waste plastic. This is because when the plastic is pulverized, the flammability is remarkably improved, and it can be a useful fuel resource.

[0003] Conventional technologies for converting plastics into solid fuels are described, for example, in "Plastics Vol. 47, No. 7, p.
60, as described in
It is finely pulverized by a pulverizer. However, in this method, hard plastics can be ground only to a particle size of 1 to 2 mm, and this grinding requires a lot of time and cost,
In addition, since fibrous or film-shaped plastics are difficult to pulverize, they must be separately pulverized after melting and solidifying, which causes a problem that the process becomes complicated.

Further, plastics containing chlorine, such as polyvinyl chloride, are subjected to heat treatment to generate hydrogen chloride gas and corrode containers and piping. It is necessary to do hydrogen chloride. For this reason, a method of treating plastic using a solvent has been proposed. That is, a method for treating plastic in petroleum or mineral oil is disclosed (see Japanese Patent Publication No. 57-16160 and Japanese Patent Publication No. 52-38594).

However, the solid obtained by the above method is
It is in a swollen state, is difficult to pulverize, and is liable to agglomerate during and after pulverization of the obtained solid, and is liable to be clogged when transported by piping. That is, it is difficult to obtain a fine solid fuel which is excellent in flammability and easy to handle by the above-mentioned conventional method.

Further, waste vinyl chloride is dissolved in a solvent,
A method of regenerating polyvinyl chloride by removing the solvent (see International Publication No. W 094/06854) is disclosed,
Since the purpose is to regenerate vinyl chloride, it is treated at a low temperature so that dehydrochlorination does not occur and the structure of polyvinyl chloride does not collapse. Therefore, since this regenerated material contains chlorine and is subjected to low-temperature treatment, it is naturally not suitable for use as a solid fuel because it is difficult to pulverize.

Further, there is disclosed a technique of mixing waste plastic with a solvent, subjecting the mixture to a decomposition reaction, and finally converting the plastic to liquid fuel or gas (Japanese Patent Publication No. 52-22672). JP-A-7-207279,
These methods are not, of course, techniques for obtaining a solid fuel.

[0008]

DISCLOSURE OF THE INVENTION The present invention is to solve the above-mentioned problems advantageously, and can be processed even if films are mixed, and can be simultaneously dehydrochlorinated. Object of the present invention is to provide a plastic processing method capable of obtaining a plastic processing product that can be easily processed, a solid fuel by the processing method, a reducing agent for ore, and a method of injecting plastic into a vertical furnace using the processing method. And

[0009]

Means for Solving the Problems In the course of studying various methods for achieving the above-mentioned object, the present inventors have made it possible to mix a plastic and an organic solvent at a temperature of 150 ° C. or more by mixing them. By cutting a part of the plastic bond with heat and an organic solvent, and then removing low-boiling components such as an organic solvent and a plasticizer, it is possible to convert the plastic into a very crushable plastic processed product. This has been newly found, and the present invention has been achieved.

According to the present invention, since dehydrochlorination can be performed simultaneously in the processing step, chlorine-containing plastics such as polyvinyl chloride can be processed together with other plastics. For this reason, when the obtained processed plastic is used as a solid fuel or the like, there is no generation of hydrogen chloride.

That is, in the first invention, a plastic and an organic solvent are mixed at a temperature of 150 ° C. or more, and after dissolving and / or swelling the plastic, an organic solvent or an organic solvent in the obtained processing solution is obtained. This is a plastic processing method characterized by removing and solidifying both a solvent and a low boiling component. In the above-mentioned first invention, it is more preferable to provide a step of removing insoluble components in the processing solution.

That is, a more preferred embodiment of the first invention is that the plastic and the organic solvent are mixed at a temperature of 150 ° C. or more, and the plastic is dissolved and / or swelled. A plastic processing method characterized by removing insoluble components in the solution, and then removing and solidifying an organic solvent or both an organic solvent and a low-boiling component in the processing solution (the first invention). Preferred Embodiment 1).

Further, another preferred embodiment of the first invention is obtained by mixing a plastic and an organic solvent at a temperature of 150 ° C. or more and dissolving and / or swelling the plastic. This is a method for treating plastic, comprising removing an organic solvent or both an organic solvent and a low-boiling component from a treatment liquid, and then removing and solidifying an insoluble component in the treatment liquid (first invention). Second preferred embodiment).

Further, in the first and second preferred embodiments of the first invention and the first invention, the organic solvent or both the organic solvent and the low-boiling component in the treatment liquid are used. At the time of removal, it is preferable to remove １ ／ or more of the weight of the organic solvent held in the reactor in order to dissolve and / or swell the plastic (third preferred embodiment of the first invention).

Further, in the first and third preferred embodiments of the first invention and the first invention described above, the first and second preferred embodiments are obtained by removing an organic solvent or both an organic solvent and a low-boiling component. After starting the cooling of the processing liquid from the processing temperature at the time of the removal.
It is preferable to cool and solidify to 100 ° C. or less within 10 minutes (fourth preferred embodiment of the first invention). In addition, the first
In the first preferred embodiment to the fourth preferred embodiment of the first invention, the organic solvent is selected from coal-based tar, a distillate of coal-based tar and a petroleum-based organic solvent. It is preferable that the number of species is two or more (fifth preferred embodiment of the first invention).

[0016] In the fifth preferred embodiment of the first invention, the distillate of the coal-based tar is selected from crude naphtha oil, naphthalene washing oil, creosote oil and anthracene oil. It is preferable to use one or more of them (sixth preferred embodiment of the first invention). In the fifth preferred embodiment and the sixth preferred embodiment of the first invention described above, the petroleum organic solvent is one or more selected from A heavy oil, C heavy oil, light oil and kerosene. (Seventh preferred embodiment of the first invention).

The first invention and the first to seventh preferred embodiments of the first invention are directed to a method for treating a plastic, wherein the plastic is a plastic containing chlorine-containing plastic in the plastic. (Eighth preferred embodiment of the first invention). Furthermore, in the first invention, the first preferred embodiment to the eighth preferred embodiment of the first invention, the first invention, the first preferred embodiment to the eighth preferred embodiment of the first invention are described. It is preferable to pulverize the solidified product obtained by any of the methods for treating plastic according to the embodiment (a ninth preferred embodiment of the first invention).

The second invention is the first invention, the first invention described above.
A solid fuel which is a plastic processed product obtained by any one of the first to ninth preferred embodiments of the invention. A third invention is a reducing agent for ore, which is a plastic processed product obtained by any of the first and ninth preferred embodiments of the method for treating a plastic according to the first invention and the first invention. It is.

A fourth invention is the first invention, the first invention.
The method according to any one of the first to ninth preferred embodiments of the present invention, wherein the plastic treated product obtained by any one of the methods for treating plastic is blown into a raceway of a vertical furnace for producing pig iron. This is a method of blowing plastic into a mold furnace.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention relates to the present invention.
I. Plastic, II. Organic solvent, III. Mixing of plastic and organic solvent, heating process, IV. Organic solvent, low boiling point component, insoluble removal process, V. Cooling, solidification process, VI. This will be described in further detail. [I. Plastics:] Plastics that are subject to the present invention, in addition to virgin plastics, are generated during the dismantling process of waste plastics and containers and packaging materials contained in municipal garbage and industrial waste, as well as electrical appliances and automobiles. Waste plastics and the like.

Specifically, all materials such as polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polystyrene, polyethylene terephthalate, polycarbonate, nylon and other thermoplastic resins and thermosetting resins are applicable. Only one of them may be used, or two or more of them may be used.

In particular, according to the present invention, a halogen element such as chlorine contained in a plastic becomes a hydrogen halide such as hydrogen chloride during processing and is easily separated, so that polyvinyl chloride, polyvinylidene chloride, chlorine A chlorine-containing plastic containing a halogen element, such as polyethylene chloride, may be included. Therefore, according to the present invention, it is not necessary to sort waste plastic, which is also very advantageous.

Further, as the raw material plastic used in the present invention, waste plastic contained in municipal garbage, industrial waste, general waste, and the like, and waste plastic generated in the disassembly process of container and packaging materials, electric appliances, automobiles and the like are preferable. . These waste plastics may contain fibers, trees, glasses, metals, etc. other than plastics.

This is because, according to the present invention, substances other than the above-mentioned plastics can be removed in a step of removing insoluble components in the present invention described later. Further, when the treatment is performed in accordance with the method of the present invention, a plastic treated product substantially containing almost no halogen element such as chlorine can be obtained. The shape and size of the plastic used in the present invention may be roughly crushed, and a size of about 10 cm square is sufficient.In general, waste plastic does not need to be crushed again and is in a state of being recovered. And film-like, sheet-like and fibrous plastics can be treated as they are.

Although finely crushed dissolves faster in the solvent, the cost of crushing increases accordingly. [II. Organic solvent:] The type of organic solvent used in the present invention is not limited as long as it dissolves and / or swells plastic.

However, in the present invention, since the plastic is heated to 150 ° C. or more during heat treatment, the boiling point of the plastic is 150 ° C.
It is preferable to use one having a temperature of not less than ° C. When a mixed organic solvent such as a coal-based tar and / or a distillate of a coal-based tar described below is used, it is preferable to use one having a 10% by weight distillation temperature of 150 ° C. or higher.

[0027] Even if the boiling point is less than 150 ° C, it can be used at 150 ° C or more and under pressurized conditions.
Among the organic solvents, it is preferable to use coal-based tar and / or a distillate of coal-based tar as the organic solvent having an appropriate boiling point range and excellent solubility. Specifically, coal-based tar, crude naphtha oil, naphthalene washing oil, creosote oil, and anthracene oil, which are distillation distillates of coal-based tar, are suitable.

These solvents may be used alone or as a mixture of two or more of them. The temperature at which hydrogen chloride is desorbed from polyvinyl chloride is usually 250 ° C or higher. However, when coal-based tar and / or a distillate of coal-based tar is used as a solvent, the temperature is 200 ° C or lower. However, dehydrochlorination occurs.

Further, the above-mentioned crude naphtha oil dissolves almost all plastics such as polyvinyl chloride,
It is particularly preferable because the rate of dehydrochlorination at a temperature of not more than ° C is high. Further, as the organic solvent used in the present invention, a petroleum organic solvent is also preferable. Petroleum organic solvents include heavy oil A, C
It is more preferable to use one or more selected from heavy oil, light oil and kerosene.

This is because when these petroleum-based organic solvents are used, the chlorine content in the resulting plastic processing product is smaller than when using coal-based tar and / or a distillate of coal-based tar as a solvent. Because. In the present invention, a coal-based tar and / or a distillate of a coal-based tar and a petroleum-based organic solvent may be mixed and used. [III. Mixing of plastic and organic solvent, heating process:]
In the present invention, the plastic and the organic solvent
A mixed state is obtained at the above temperature.

The weight ratio of the organic solvent and the plastic in the mixture of the plastic and the organic solvent, that is, the preferred range of the organic solvent / plastic [weight ratio] is 0.1 to 0.1.
10, more preferably in the range of 0.5 to 5. When the weight ratio is less than 0.1, the viscosity of the system becomes high, handling becomes difficult, and dechlorination hardly occurs.

On the other hand, if the weight ratio exceeds 10, it is disadvantageous in terms of the size of the reaction vessel and the distillation cost for removing the organic solvent from the plastic processing product. The method of mixing the plastic and the organic solvent at a temperature of 150 ° C. or higher is not particularly limited. For example, after mixing a plastic and an organic solvent at room temperature, heat it to a temperature of 150 ° C or higher,
The temperature may be increased, or one or both of the plastic and the organic solvent may be heated to a temperature of 150 ° C. or higher, and then mixed.

The mixed system of the plastic and the organic solvent obtained by making such a mixed state may be a uniform system (all dissolved) or a solid (swelled) part of which cannot be completely dissolved. You may. When the temperature of the plastic is raised to 150 ° C or higher in the presence of an organic solvent, the entanglement of the polymer of the plastic is loosened, some bonds are broken, and the strength of the solid after removal of the solvent is reduced. Fine pulverization of the processed material becomes easy.

When the temperature of the system in the above mixed state is 150
If the temperature is lower than 0 ° C, the hardness of the solid obtained after removing the solvent is almost the same as that of the original plastic, and it is difficult to pulverize the solid. On the other hand, if the temperature of the system in the mixed state rises above 450 ° C., the yield of solids decreases due to gasification or oilification of the plastic. Therefore, in the present invention, the temperature of the mixed system of the plastic and the organic solvent is specified to be 150 ° C. or higher, and the upper limit is preferably 450 ° C., more preferably the temperature range of 160 to 400 ° C. More preferably, 180-380 ° C, and even more preferably, 200-35 ° C.
The temperature range is 0 ° C.

In order to dechlorinate chlorine-containing plastics such as polyvinyl chloride and polyvinylidene chloride to generate hydrogen chloride, the temperature of the system in a mixed state must be 150 ° C. or higher. System temperature in mixed state is 150
If the temperature is lower than ℃, the reaction rate of dechlorination is insufficient, which is not practical.

On the other hand, if the temperature of the system in the mixed state is too high, as described above, the gasification or oilification of the plastic lowers the yield of solids, so that the temperature is preferably 450 ° C. or lower. Mixtures of plastics and organic solvents 1
After being mixed at a temperature of 50 ° C. or higher, it is preferable to maintain the mixture at a temperature of 150 ° C. or higher for a certain period of time.

During this time, it is preferable to reflux the solvent. It is preferable that the holding time at a temperature of 150 ° C. or more is longer, because dehydrochlorination can be performed more reliably and the solid after removal of the solvent becomes brittle. However, if the time is too long, decomposition and gasification proceed, causing problems such as a decrease in the yield of the target solid and a decrease in the processing capacity of the equipment.

For this reason, the time for maintaining the temperature at 150 ° C. or higher is preferably 10 minutes to 6 hours, more preferably 30 minutes to 6 hours.
The range is 3 hours. In the above-mentioned step of mixing, the mixing and heating may be performed separately, but may be performed continuously using the same container, and naturally, it is more economical to perform continuously. .

Further, these treatments may be performed by a batch system or a continuous system. [IV. Step of Removing Organic Solvent, Low Boiling Component, and Insolubles:] In the present invention, the organic solvent in the heat-treated product (: treatment liquid) (: mixture) obtained in the mixing and heating steps described above, or Both organic solvents and low boiling components are removed.

In the present invention, the mixing,
Heat-treated product obtained in the heating step (: treatment liquid) (: mixed liquid)
It is more preferable to remove the organic solvent or both the organic solvent and the low-boiling component from, and to remove the insoluble components. According to the present invention, by removing the organic solvent, or both the organic solvent and low-boiling components from the heat-treated product described above, the resulting plastic processed product is extremely easy to pulverize, and the secondary aggregation of the pulverized product is further reduced. Become something.

Further, according to the present invention, a plastic processed product having a low chlorine content can be obtained by removing insoluble components from the above-mentioned heat-treated product. The removal of the organic solvent and low-boiling components can be performed by a known method such as distillation and drying. In the case of performing distillation, simple simple distillation is also possible, and any of a batch method and a continuous method can be applied.

In any of these cases, the pitch-shaped residue (residue) is taken out by an appropriate method, and cooled to obtain a target solid. The distillation temperature is preferably between 150 and 400 ° C. Either atmospheric distillation or vacuum distillation may be used as the distillation method, but vacuum distillation is preferable because the efficiency of removing low-boiling components is higher, and the distillation is preferably carried out under the conditions of atmospheric pressure of the object to be treated ≦ (atmospheric pressure−500 Torr). It is more preferable to use the reduced pressure distillation method described above.

On the other hand, when the drying method is used, it is possible to use a method of storing in a container of an arbitrary size and treating in a kiln. The processing temperature for the drying method is 150
~ 400 ° C is preferred. In the present invention, it is also possible to remove low boiling components by a spray drying method. in this case,
It is preferred to spray the plastic at a temperature of from 150 to 400 ° C.

The low-boiling components removed in this step are reaction products such as hydrogen chloride, low-molecular-weight components obtained by decomposing plastic, plasticizers in plastics, additives for plastics, and thermal decomposition products thereof. . In the present invention, when removing the organic solvent or both the organic solvent and the low-boiling component in the heat-treated product (: treatment liquid) (: mixture) obtained in the above-mentioned mixing and heating steps, the plastic is dissolved. It is preferable to remove １ ／ or more of the weight of the organic solvent held in the reactor in order to swell and / or remove more than ／ of the weight of the organic solvent held in the reactor. Is more preferred.

By removing at least half of the weight of the organic solvent held in the reactor, the pulverizability of the plastic processed product obtained after cooling and solidification becomes extremely good. This is because secondary agglomeration of the pulverized particles can be prevented. The weight of the organic solvent held in the above-described reactor indicates the maximum held weight of the organic solvent held in the reactor.For example, in the case of a batch type reactor, usually, the reactor was charged before the start of the reaction. It is indicated by the weight of the organic solvent.

The weight of the removed organic solvent is
The amount of the processed plastic obtained after the solidification can be measured, and the amount of the organic solvent in the processed plastic can be determined by gas chromatography or liquid chromatography. Furthermore, the weight of the removed organic solvent can also be determined by measuring the amount of the removed liquid and analyzing the removed liquid by gas chromatography or liquid chromatography.

In this step, the organic solvent and low-boiling components do not have to be completely removed. In other words, it is sufficient that the plastic processed material obtained after cooling and solidification has excellent pulverizability and is easily pulverized, and can be easily transported. The organic solvent and the low boiling point in the range of 50 wt% or less in the processed material can be obtained. Ingredients may remain. In order to improve the ignitability in a boiler or the like when used as a fuel, it is also effective to leave a solvent in the processed material.

According to the present invention, the smaller the amount of the organic solvent remaining in the processed plastic product, the easier the obtained plastic processed product is to be pulverized and the pulverized product does not agglomerate.
Severe conditions (high temperature and high vacuum) are required for desolvation,
Conversely, if the amount of the solvent remaining in the plastic processed material is large, the transfer of the residue (residue) becomes easy, but it becomes difficult to pulverize the obtained plastic processed material, and the pulverized material is easily aggregated and the solvent is removed. The cost is high.

The organic solvent and low-boiling components removed in the above steps may be reused in the above-mentioned mixing and heating steps. Further, as described above, in the present invention, the organic solvent or both the organic solvent and the low-boiling component are removed from the heat-treated product (: treatment liquid) (: mixture) obtained in the mixing and heating steps described above. In addition, it is more preferable to remove insoluble components.

By removing insoluble components from the heat-treated product, a plastic-processed product having a low chlorine content can be obtained. The removal of insoluble components can be performed by a solid-liquid separation method such as filtration, standing separation, and centrifugation. The removal of insolubles is preferably carried out at a temperature of 150 to 400 ° C.

The insoluble components to be removed include not only inorganic substances such as glass and metal and paper contained in the treated product containing the plastic, but also carbides which are easily generated after dechlorinating chlorine-containing plastics such as polyvinyl chloride. According to the present invention, the chlorine content in the obtained plastic processed product can be further reduced by removing the insoluble components according to the present invention.

The temperature at the time of removing the organic solvent, low-boiling components and insoluble components does not need to be the same as the temperature of the mixing and heating steps in the preceding step. Rather, the higher the temperature in the mixing and heating steps, the easier the removal. ,preferable. The removal of insolubles may be performed after the above-described mixing and heating steps, before removing the organic solvent and low-boiling components, or after removing the organic solvent and low-boiling components, What is necessary is just to judge from the aspect of the viscosity of the processed material in the process of removing insoluble components. [V. Cooling and solidifying step:] In the present invention, an organic solvent,
After removing low boiling components and insolubles, the treated product is solidified.

As a cooling method at the time of solidification, it is possible to use a method such as standing cooling or charging in water, and it is not particularly limited. The cooling rate after removing the organic solvent, low-boiling components, and insolubles is not particularly limited, but the higher the cooling rate, the more easily the obtained plastic processed product is pulverized.

Therefore, in the present invention, an organic solvent,
Alternatively, it is preferable to cool and solidify the treatment liquid obtained by removing both the organic solvent and the low-boiling component from the treatment temperature at the time of the removal to 100 ° C. or less within 10 minutes after the start of cooling. [VI. Pulverizing Step:] It is preferable that the lump of the plastic processed product obtained in the cooling and solidifying step is pulverized to have a predetermined particle size.

The pulverization of the processed plastic obtained by the method of the present invention can be performed very easily as compared with the pulverization of untreated plastic. Therefore, the plastic processed product obtained by the method of the present invention can be pulverized with any type of pulverizer, for example, jaw crusher,
Roll crushers, ball mills, centrifugal mills, etc. can be applied.

The particle size may be determined according to the purpose of use. If the particle size is adjusted to a predetermined particle size, for example, an ore reducing agent such as iron ore, that is, a reducing agent for a vertical furnace such as a blast furnace for producing pig iron. It can be used as raw fuel such as boiler, combustion fuel such as boiler and kiln, and fuel for cupola. Also,
It can be used as a solid fuel in addition to the uses described above.

When used as a reducing agent in a vertical furnace for producing pig iron such as the above-mentioned blast furnace, it can be charged from the furnace top of the vertical furnace, but the plastic is used as a reducing agent and as a fuel. From the viewpoint of efficiency, it is preferable to blow the plastic processing product obtained by the plastic processing method of the present invention into a raceway formed in front of a blowing tuyere of a vertical furnace for manufacturing pig iron.

In this case, as described above, it is preferable to blow the pulverized product of the solidified product obtained by the plastic processing method of the present invention into a raceway. As a method of blowing into the raceway, a blow pipe method,
It is possible to use any of the tuyere blowing method,
The blowing method is not particularly limited.

As described above, the plastic processed product obtained by the plastic processing method of the present invention has a low chlorine content even when a chlorine-containing plastic is used as a raw material. Therefore, the reducing agent in a blast furnace, a boiler, a kiln, a cupola or the like is used. When used as a fuel, it has an excellent effect that chemical erosion of refractories due to chlorine or chlorine compounds can be prevented.

[0060]

EXAMPLES The present invention will be described below more specifically based on examples. (Example 1) In a stainless steel reactor having an internal volume of 5 l, 1500 ml of creosote oil, which is a distillate of coal-based tar in a coke oven, was used as an organic solvent, and polyethylene (film), polypropylene (plate), and polystyrene were used. (Plate-shaped) and polyethylene terephthalate (fibrous) cut into about 10 cm square or about 10 cm length were each charged in 300 g, and the temperature was started to rise by the heater on the outer wall of the reactor.

Incidentally, the component analysis values of the plastic mixture in the above-mentioned amounts of the four types of plastics are as follows:
C: 81 wt%, H: 11 wt%, and O: 8 wt%. After the temperature of the treated product in the reactor reached 280 ° C., the organic solvent was refluxed at the temperature for 2 hours. As a result, most of the plastic was dissolved, and a viscous liquid was obtained.

Next, the obtained liquid was distilled under reduced pressure (absolute pressure: 50 Torr) at a temperature of 300 ° C., and desolvation treatment (including a component having a low boiling point) was carried out. As a result, a pitch-like residue was obtained. When this was cooled to room temperature, it became a black coal-like solid (: lump). 50 g of this black lump was charged into a rotary blade pulverizer and pulverized. As a result, pulverization was extremely easy, and a fine powder having an average particle diameter of 1 mm was obtained in a pulverization time of 20 seconds.

Table 1 summarizes the processing conditions in this example, and the test results such as the component analysis value of the obtained lump and the pulverization state. The component composition of the organic solvent (creosote oil) used in this example is shown in Table 1. Are shown in Table 2. The deorganized solvent ratio shown in Table 1 indicates the weight ratio (%) of the removed organic solvent to the weight of the organic solvent held in the reactor, that is, the weight of the organic solvent charged to the reactor before the start of the reaction.

[0064]

[Table 1]

[0065]

[Table 2]

(Examples 2 to 25 and Comparative Examples 1, 2, and 3)
A mixture of the following various plastics and the following various organic solvents, which are different from Example 1 in formulation, were used, except that the conditions for heating and holding or refluxing and the conditions for desolvation were changed.
The same treatment as in Example 1 was performed to obtain solid lumps. In Examples 2 to 24, after the plastic and the organic solvent were heat-treated in a mixed state, hot filtration was performed at the same temperature as the heat treatment to remove solid insoluble components. The components were removed, then cooled and solidified.

In Example 25, after the heat treatment was performed in a mixed state of the plastic and the organic solvent, the organic solvent and the low-boiling components were removed from the processing solution, and the temperature was the same as that when the organic solvent and the low-boiling components were removed. Hot filtration was performed at the temperature, followed by cooling and solidification. In Comparative Example 3, after the plastic and the organic solvent were heat-treated in a mixed state, the organic solvent and the low-boiling components were not removed, and the mixture was cooled and solidified as it was. [Plastic mixture used:] (Type, shape, blending amount :) Polyethylene (film, about 10 cm square); 300 g Polypropylene (plate, about 10 cm square); 300 g Polystyrene (plate, about 10 cm square); 300 g Polyvinyl chloride (plate, about 10 cm square); 300 g Polyethylene terephthalate (fibrous, about 10 cm long); 300 g (Analytical value of the above plastic mixture: C: 73 wt%, H: 9 wt%, O: 7 wt% , Cl: 11 wt% [organic solvent used]; distillate of coal-based tar ... creosote oil, naphthalene washing oil, crude naphtha oil having the composition shown in Table 2 above; coal-based tar; petroleum-based Organic Solvent: Heavy Fuel Oil A, Heavy Fuel C, Light Oil, Kerosene Next, the solid mass obtained above was pulverized using the same pulverizer as in Example 1, and the pulverization time and average particle size were measured.

Table 3 (Examples 2 to 25) and Table 4 (Comparative Examples 1 and 2) show the processing conditions and test results in the present Example and Comparative Example.
2, 3) are shown together. The organic solvent removal rates shown in Tables 3 and 4 are based on the organic solvent held in the reactor, that is,
The weight ratio (%) of the removed organic solvent to the weight of the organic solvent charged into the reactor before the start of the reaction is shown.

Example 26 The treatment was performed using shredder dust having the contents and compositions shown in Tables 5 and 6 (crushed debris generated when crushing waste including home electric appliances and the like). That is, 750 g of shredder dust was added to 1500 ml of creosote oil, and heated and maintained at 250 ° C. for 2 hours.

As a result, most of the plastic was dissolved and hydrogen chloride gas was generated, and a viscous liquid was obtained.
Next, the obtained liquid was subjected to hot filtration at 250 ° C. to remove insoluble substances (insoluble components) such as glass and metal. Next, this viscous filtrate was subjected to vacuum distillation at 300 ° C. [50 Torr (absolute pressure), 2 hours, deorganizing solvent ratio: 93 wt%], and as a result, a pitch-like residue was obtained.

Thereafter, the pitch-like residue is cooled to room temperature,
A black coal-like solid was obtained. In addition, 25
The time required to cool from 0 ° C. to 100 ° C. was 3.5 minutes. Next, 5 g of the obtained black lump was charged into a desktop centrifugal mill and pulverized. The time required for the average particle size of the pulverized product to be 1 mm was 20 seconds.

Table 6 shows the elemental analysis values of the black mass obtained.

[0073]

[Table 3]

[0074]

[Table 4]

[0075]

[Table 5]

[0076]

[Table 6]

[0077]

[Table 7]

[0078]

[Table 8]

[0079]

[Table 9]

[0080]

[Table 10]

[0081]

[Table 11]

[0082]

[Table 12]

[0083]

[Table 13]

Comparative Example 4 Polyethylene (film form,
About 1 cm square), polypropylene (plate, about 1 cm square), polystyrene (plate, about 1 cm square), polyvinyl chloride (plate,
About 1 cm square), polyethylene terephthalate (fibrous, about
10 g each (10 cm long) was put into a rotary blade type pulverizer and pulverization was attempted.

However, the film-like or fibrous plastic was entangled with the rotary blade and could not be crushed. Example 27, Comparative Example 5 Plastic was treated in the same manner as in Example 17 to obtain about 500 kg of a processed product. The obtained cooled solidified product is charged together with coal into a roller mill for coal grinding,
It was pulverized, and the pulverized product was fed to the blast furnace by pneumatic transportation, and was blown from the tuyere of the blast furnace (Example 27).

As a comparison, only pulverized coal obtained by pulverizing with the above-mentioned roller mill for coal pulverization was fed to the blast furnace by air transport, and was blown from the tuyere of the blast furnace (Comparative Example 5).
. Table 7 shows the injection amount of the pulverized plastic processed product, the pulverized coal (pulverized coal) injection amount, and the blast furnace fuel ratio in Example 27 and Comparative Example 5. The fuel ratios shown in Table 7 are for pig iron 1
Shows the total amount of coke, pulverized coal and pulverized plastic products consumed per t.

[0087]

[Table 14]

As shown in Examples 1 to 26 described above, it is understood that the plastics treated by the method of the present invention have extremely excellent pulverizability and low chlorine content. On the other hand, when the organic solvent and the low-boiling components were not removed (Comparative Example 3), the obtained plastic processed product had a high chlorine content, was poor in pulverizability, and easily aggregated.

As shown in Example 27 and Comparative Example 5, when the pulverized product of the plastic product of the present invention was used as a reducing agent for iron ore in a blast furnace, the fuel ratio of the blast furnace could be reduced. Was. Further, the treated plastic product of the present invention could be used as a solid fuel for boiler and kiln combustion.

[0090]

According to the present invention, a plastic and an organic solvent are mixed and heated at a specific temperature or higher to dissolve and swell.
An organic solvent, a method for treating a plastic that removes low-boiling components and solidifies, and a solid fuel and an ore reducing agent obtained by the treatment method. ADVANTAGE OF THE INVENTION According to this invention, the problem in the direct grinding | pulverization method of a plastic is improved significantly.

That is, according to the present invention, the following excellent effects can be obtained. Firstly, for example, the direct pulverization of plastic into, for example, 1 to 2 mm square is not required, and the preliminary pulverization to a size that can be dissolved in a solvent, that is, about 10 cm square is sufficient. Second, by removing the organic solvent and low-boiling components after the heat treatment, the plastic-treated product after the removal of the solvent is very easily pulverized, and has an effect of excellent pulverizability.

Thirdly, film-like or fibrous plastics can be processed simultaneously with plastics of other shapes.
Fourth, chlorine-containing plastics, such as polyvinyl chloride, can be processed simultaneously with other plastics.
That is, dehydrochlorination is also possible under mild conditions, the generated hydrogen chloride can be easily separated, and when dehydrochlorination is performed in the presence of a solvent, the dechlorination is lower than that of dechlorinated polyvinyl chloride without a solvent. Because of the viscosity, there is no transportation problem.

Fifth, since the plastic processed product obtained by the method of the present invention is extremely excellent in pulverizability, fine powder substantially containing no chlorine can be obtained, and non-pollution excellent in flammability can be obtained. Can be used as a fuel, a reducing agent and the like. Furthermore, since the processed plastic obtained by the method of the present invention does not substantially contain chlorine as described above,
Reducing agents in blast furnaces, boilers, kilns, cupolas, etc.
When used as a fuel, it has an excellent effect that it is possible to prevent chemical erosion of refractories by chlorine or chlorine compounds.

Further, the method of the present invention can perform continuous processing, so that it is not necessary to use complicated and expensive equipment, and if a large reaction vessel is used, large-scale processing can be performed. Is also excellent.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kimihiro Nishimura 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Inside the Technical Research Institute of Kawasaki Steel Corp. (72) Makiko Ijiri 1, Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Kawasaki (72) Inventor Masahiko Tada 1 in Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture In-house Technical Research Laboratory (72) Inventor Masafumi Komatsu 2-3-2 Uchisaiwai-cho, Chiyoda-ku, Tokyo Kawasaki Steel Corporation (72) Inventor Hiroyuki Uesugi 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawatetsu Techno-Research Corporation

Claims (5)

[Claims] 1. A plastic and an organic solvent are mixed at a temperature of 150 ° C. or higher, and after dissolving and / or swelling the plastic, an organic solvent or an organic solvent and an organic solvent and a low boiling point component in the obtained processing solution are obtained. A plastic processing method comprising removing and solidifying both. 2. The method according to claim 1, wherein when removing the organic solvent or both the organic solvent and the low-boiling component in the treatment liquid, the weight of the organic solvent retained in the reactor to dissolve and / or swell the plastic. 2. The method for treating plastic according to claim 1, wherein at least half of the plastic is removed. 3. A solid fuel which is a plastic processed product obtained by the method for processing plastic according to claim 1. 4. A reducing agent for ore, which is a processed plastic product obtained by the method for processing plastic according to claim 1 or 2. 5. A plastic injection into a vertical furnace, wherein the plastic processing product obtained by the method for processing plastic according to claim 1 or 2 is injected into a raceway of a vertical furnace for producing pig iron. Method.