JP2007001153A - Melting solidification method and melting solidification apparatus for waste plastic - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide, regarding a method and an apparatus for solidifying film-form, soft waste plastics and supplying as a substitute for solid fuels such as coal, a solidification method and an apparatus low in the apparatus manufacturing cost and the apparatus operating cost. <P>SOLUTION: An apparatus is manufactured which comprises an upper box, a lower box having a heater on the side wall part and/or on the bottom, a hopper having a heater on the side wall part, a screw feeder having a heater in the periphery, a means to apply load to the waste plastics and a means to cut and cool the molten waste plastics. The temperature of the side wall part and/or the bottom of the lower box, that of the side wall part of the hopper and that of the periphery of the screw feeder are maintained in the range of 100-400°C, 100-300°C and 100-250°C, respectively. This unnecessitates the power for pre-crushing, reduces the power for extrusion by the screw feeder and decreases the power for operation due to decreased electric power for heating, thus achieving a cheap manufacturing of the apparatus and a low operation cost. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a method and an apparatus for supplying, as a substitute for solid fuel such as coal, by melting and solidifying a film-type soft waste plastic among waste plastics discharged as waste.

Waste plastics discharged as waste have a high calorific value and can be reused as an alternative to solid fuels such as coal. However, it is difficult to reuse film-based soft waste plastics as they are. In the past, a method of solidifying into a lump and reusing it as a substitute for solid fuel such as coal has been proposed. The conventional solidification method will be described below.

Japanese Patent Application Laid-Open No. 2004-136632 shows a method for granulating waste plastics, in which a rotary blade is mounted inside a bowl-shaped cylindrical container and soft film waste plastics that are roughly crushed in advance are mounted. The waste plastics are crushed by the rotation of the blades, and the waste plastics are semi-melted, agglomerated and solidified by frictional heat generated by the rotating contact.

On the other hand, Japanese Patent Application Laid-Open No. 6-143255 and pamphlets of Horai Co., Ltd. and Plako Co., Ltd. show a method for granulating waste plastics. A roller is installed in the film, soft film plastic waste that has been crushed in advance is charged, and the waste plastics are semi-melted and agglomerated by frictional heat generated by the rotating contact of the roller. It is extruded to the outside and cut into an appropriate size at the outlet.
JP 2004-136632 A JP-A-6-143255

However, in the granulation method of waste plastics proposed in Japanese Patent Application Laid-Open No. 2004-136632, a solidified product of about 5 mm is manufactured and can be reused as an alternative to solid fuel. Are also generated at the same time and are difficult to handle. Moreover, since the rotational power of a blade | wing is large and the power for prior crushing is required, there exists a fault that the electric power basic unit which occupies most operating costs of an apparatus is high, and operating cost is high. Also, the device manufacturing cost is high due to the complicated structure.

Moreover, in the granulation method of waste plastics proposed in Japanese Patent Application Laid-Open No. 6-143255 and pamphlets of Horai Co., Ltd., Plako Co., Ltd., a solidified product having a diameter of 5 to 10 mm and a length of about 50 mm is produced. It can be reused as an alternative to solid fuel. However, since the rotational power of the roller is large and the power for pre-grinding is necessary, there is a drawback that the power consumption unit occupying most of the operating cost of the apparatus is high and the operating cost is also high. Also, the device manufacturing cost is high due to the complicated structure.

Based on the above, the problem in the method of supplying film type soft waste plastics as a substitute for solid fuel such as coal is to reduce the device manufacturing cost and the device operating cost. It is to be.

The present invention has been made in view of the above problems, and melts plastic soft plastics without pre-crushing, and reuses the melted plastics as an alternative to solid fuel such as coal. An object of the present invention is to provide a method for melting and solidifying waste plastics and a melting and solidifying device, which can achieve an inexpensive device manufacturing cost and an inexpensive device operating cost.

In order to achieve the above object, the waste plastic melting and solidifying method according to the first aspect of the present invention includes an upper box-type box in which waste plastics are charged, and a side wall and / or a lower part of the upper box-type box. Or a lower box-type box with a heater installed at the bottom, a hopper with a heater installed at the side wall at the bottom of the lower box-type box, and a heater installed at the periphery of the hopper outlet Equipped with a screw feeder, equipped with means for applying a load to the waste plastics charged in the upper box-type box, and equipped with means for cutting and cooling the molten waste plastic flowing out from the screw feeder outlet. It is characterized by.

The invention according to claim 2 is the method for melting and solidifying waste plastics according to claim 1, wherein the temperature of the side wall and / or bottom of the lower box-type box is maintained in the range of 100 to 400 ° C. The temperature of the side wall portion of the hopper is maintained in the range of 100 to 300 ° C., and the temperature of the peripheral portion of the screw feeder is maintained in the range of 100 to 250 ° C.

Furthermore, the waste plastics melting and solidifying device according to the third aspect of the present invention is provided by being connected to an upper box-type box in which the waste plastics are charged, and a lower part of the upper box-type box. Alternatively, a lower box box in which a bar heater and / or a winding heater is installed at the bottom, and a hopper that is connected to the lower part of the lower box box and has a bar heater installed in the side wall, and a hopper A screw feeder with an annular heater installed in the periphery, a lower box-type box, a hopper, a temperature detection means installed near the screw feeder heater, and an upper box-type box A means for applying a load to the waste plastics charged in and a means for cutting and cooling the molten plastics flowing out from the screw feeder outlet. Characterized in that it comprises a.

According to the method for melting and solidifying soft waste plastics of the film system proposed in the present invention, it is not necessary to crush waste plastics in advance, as will be described later. By heating and melting, the extrusion power by the screw feeder is reduced. In addition, by adopting an appropriate heating method for waste plastics, the heating power can be reduced, the overall operating power is reduced, and an inexpensive apparatus operating cost can be achieved.

In addition, the film-type soft waste plastic melting and solidifying device proposed in the present invention has a minimum required specification for solidifying into a shape that can be reused as an alternative to solid fuel such as coal. Therefore, an inexpensive device manufacturing cost can be achieved.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.

FIG. 1 is an explanatory view showing an embodiment of a method for melting and solidifying waste plastics according to the present invention and a melting and solidifying apparatus. The upper box-type box 1 for charging waste plastics can be charged, for example, in the form of a block with a compressed volume (see 11 in FIG. 1) without crushing the soft plastic waste film. It is. Therefore, since there is no need for rough crushing and pulverization in advance, the power required for these treatments becomes unnecessary.

The lower box-type box 2 connected to the lower part of the upper box-type box 1 is provided with a heater on the side wall and / or the bottom. The heater 5 at the side wall is preferably a wound heater, and the heater 6 at the bottom is preferably a rod heater protected by hardware. The bar-shaped heater at the bottom is provided in two stages in a lattice shape, thereby increasing the melting ability.

The compression-reduced block-type film-type soft waste plastic 11 charged in the upper box-type box 1 is brought into contact with the bottom heater 6 of the lower box-type box 2 by applying a load with a load device 9 from above. The rate is increased and melting is promoted.

A hopper 3 connected to the lower part of the lower box-type box 2 is provided with a heater 7 on the side wall. The heater at the side wall is preferably a rod heater protected by a hardware.

The screw feeder 4 connected to the outlet of the hopper 3 is provided with a heater 8 at the periphery. The peripheral heater is preferably an annular heater.

In the method for melting and solidifying waste plastics in the present invention, the temperature detection means (thermocouple or the like) installed on the heater 5 mounted on the side wall and / or bottom of the lower box-type box 2 and / or the hardware near the heater 6. The temperature detected by using a) is kept in the range of 100 to 400 ° C. The reason why the temperature range was set was determined by conducting experiments in advance so that the soft waste plastics of film type that are discharged as waste include those with different melting temperatures, and almost all of them can be processed. Is. When the temperature is lower than 100 ° C., the melting is insufficient, and when the temperature exceeds 400 ° C., over-melting occurs.

Next, the temperature detected by the temperature detection means (using a thermocouple or the like) installed on the hardware in the vicinity of the heater 7 mounted on the side wall of the hopper 3 is maintained in the range of 100 to 300 ° C. The setting of the temperature range was determined by conducting an experiment in advance. Since it is pre-heated by the heater 5 and / or the heater 6 of the lower box-type box 2, the upper limit temperature of the hopper 3 may be low and becomes 300 ° C. When the temperature is lower than 100 ° C, the melting is insufficient, and when the temperature exceeds 300 ° C, overmelting occurs, so that the amount of electricity used increases and the operating cost increases.

Furthermore, the temperature detected by the temperature detection means (using a thermocouple or the like) installed on the hardware in the vicinity of the heater 8 attached to the periphery of the screw feeder 4 is maintained in the range of 100 to 250 ° C. The setting of the temperature range was determined by conducting an experiment in advance. Since the heater 5 and / or the heater 6 of the lower box-type box 2 and the heater 7 of the hopper 3 are preheated, the upper limit temperature of the screw feeder 4 may be low and is 250 ° C. When the temperature is lower than 100 ° C, the melting is insufficient, and when the temperature exceeds 250 ° C, the material is overmelted, so that the amount of electricity used increases and the operation cost increases.

Furthermore, the outlet part of the screw feeder 4 is equipped with a device for cutting and cooling the flowing molten waste plastics, and has a particle size of 50 mm or less, which is a sufficient particle size to supply as a substitute for solid fuel such as coal. Cool down after cutting. As the cutting device, a method of moving the rotary blade at an appropriate rotation speed can be adopted, and as the cooling device, a method such as air cooling or water cooling can be adopted.

Hereinafter, examples of the method for melting and solidifying waste plastics according to the present invention will be described in more detail.

Example 1
Non-woven waste made of a mixture of polyethylene (PE), polypropylene (PP), and polyester is compressed and volume-reduced, and the block shape of 800 x 600 x 600 mm is inserted into the upper box box and blocked. A load was applied from above the woven nonwoven fabric with an iron plate and an iron lump.

Next, the temperatures detected by the thermocouples installed on the hardware near the side wall of the lower box-type box 2 (mounted with the winding heater 5) and the bottom of the box (mounted with the bar heater 6 protected by the hardware) are The temperature was kept in the range of 100 to 200 ° C. In addition, the temperature detected by a thermocouple installed on the hardware in the vicinity of the heater on the side wall of the hopper 3 (attached to the rod-shaped heater 7 protected by the hardware) was kept in the range of 100 to 175 ° C. Furthermore, the temperature detected by the thermocouple installed in the hardware near the heater in the periphery of the screw feeder 4 (equipped with the annular heater 8) was kept in the range of 100 to 150 ° C.

After 8 minutes from the start of heating, the melted nonwoven fabric began to flow out from the screw feeder outlet, so the rotating blade 10 installed in the vicinity of the screw feeder outlet was rotated at a frequency of several times / second to melt the melt. It was cut and dropped into a water bath and cooled. The produced solidified material was a lump of about 30 × 50 mm, and could be sufficiently supplied as a substitute for solid fuel such as coal.

Example 2
A plastic bottle label crushed product (particle size of about 10 mm) made of a mixture of polyethylene (PE), polystyrene (PS), and PET bottle (PET) is placed on the bottom of the upper box box. Laid down and loaded on it, and further loaded with a wooden board and iron ingot from above.

Next, the temperature detected by the thermocouple installed in the hardware in the vicinity of the heater at the bottom of the lower box-type box 2 (attached to the bar heater 6 protected by the hardware) was kept in the range of 100 to 350 ° C. Further, the temperature detected by the thermocouple installed on the hardware near the heater on the side wall of the hopper 3 (with the rod heater 7 protected by the hardware) was kept in the range of 100 to 300 ° C. Furthermore, the temperature detected by the thermocouple installed in the hardware near the heater in the periphery of the screw feeder 4 (equipped with the annular heater 8) was kept in the range of 100 to 250 ° C.

10 minutes after the start of heating, the melted PET bottle label started to flow out from the screw feeder outlet, so the rotating blade 10 installed near the screw feeder outlet was rotated at a frequency of 1 to 2 times / second. The melt was cut, dropped into a water bath and cooled. The produced solidified product was a lump of about 25 × 50 mm, and was sufficiently capable of being supplied as an alternative to solid fuel such as coal.

Example 3
The upper box-type box 1 in which the waste plastics are charged is made of iron in a size of 800 × 600 × 1200 mm, and is connected to the lower portion of the upper box-type box, and the lower box-type box 2 is 800 × 600 It was made of iron with a size of × 600 mm, a winding heater was installed all around the side wall, and a bar heater protected by hardware was installed in two rows in a 10 × 6 grid.

In addition, the hopper 3 is made of iron with a size of 800 × 600 × 300 mm (side wall slope 800 × 400 mm) connected to the lower part of the lower box-type box, and the side wall is protected by hardware. A book was set up. Further, the screw feeder 4 (screw having a diameter of 80 mm, a groove depth of 10 mm, and a length of 1350 mm) and a casing made of iron is connected to the outlet portion of the hopper and is not in contact with the hopper outlet portion outside the casing. In addition, an annular heater was installed.

Furthermore, a rotary blade and a rotation mechanism were installed in the vicinity of the screw feeder outlet. The screw feeder extrusion power was 7.5 kW, and the heating power of the heater was 40 kW.

The above-mentioned melting and solidifying apparatus for waste plastics achieved 1/3 to 1/4 of the manufacturing cost of the above-described conventional solidifying apparatus when compared at a processing capacity of 100 kg / hour.

The front view and side view which show embodiment of the melt-solidification method of the waste plastics in this invention, and a melt-solidification apparatus.

Explanation of symbols

1: Upper box box 2: Lower box box 3: Hopper 4: Screw feeder 5: Lower box box side wall heater 6: Lower box box bottom heater 7: Hopper side wall heater 8: Around screw feeder Heater 9: load device 10: cutting device for molten waste plastic 11: film-based soft waste plastic 12 with compression and volume reduction: electric motor

Claims (3)

In the method of solidifying waste plastics, an upper box box for charging waste plastics is provided, and a lower box box having a heater on the side wall and / or bottom is provided at the bottom of the upper box box. Equipped with a hopper with a heater installed on the side wall at the bottom of the lower box box, a screw feeder with a heater installed at the periphery at the outlet of the hopper, and loaded into the upper box box A method for melting and solidifying waste plastics, comprising means for applying a load to the waste plastics, and means for cutting and cooling molten waste plastics flowing out from a screw feeder outlet. The method for melting and solidifying the waste plastics according to claim 1, wherein the temperature of the side wall and / or the bottom of the lower box-type box is maintained in the range of 100 to 400 ° C, and the temperature of the side wall of the hopper is set to 100. A method for melting and solidifying waste plastics, characterized in that the temperature is maintained in the range of 300 to 300 ° C., and the temperature around the screw feeder is maintained in the range of 100 to 250 ° C. An upper box box in which waste plastics are charged, and a lower box which is connected to the lower part of the upper box box and has a bar heater and / or a winding heater installed on the side wall and / or the bottom. A hopper that is connected to the lower part of the mold box and the lower box type box, is provided with a hopper that has a bar heater on the side wall, and an outlet that is connected to the outlet of the hopper, and an annular heater is installed on the periphery. Screw feeder, lower box box, hopper, temperature detection means installed near the heater of the screw feeder, means for applying load to waste plastics charged in the upper box box, screw feeder outlet An apparatus for melting and solidifying waste plastics, characterized by comprising means for cutting and cooling molten waste plastics flowing out more.

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