JPH0919925A - Foam plastic volume reduction device - Google Patents

Abstract

(57) [Summary] [Purpose] Compact foam plastic volume reduction device that can easily reduce the volume of foam plastic used for food trays and packing materials by heating, and reduce the flammable gas and odor gas generated. The purpose is to provide. [Structure] A main body having a door, a storage part of foamed plastic provided inside the main body, a heating fan and a heater, and an outlet and a suction port are connected to the storage part to circulate hot air in the storage part. And a catalyst deodorizing passage provided in parallel with a part of the hot air circulating passage including the hot air supplying passage and the oxidation catalyst, and supplying a part of the hot air to the catalyst deodorizing passage. A foamed plastic volume reduction device configured as described above. Further, an air intake port is provided in the negative pressure portion downstream in the flow direction of the hot air, and a catalyst deodorizing passage in which a discharge passage downstream of the oxidation catalyst is opened to the outside through a hot air supply passage is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foamed plastic volume-reducing device for heating and compressing the foamed plastic used in food trays, packing materials, etc. generated in small-scale business establishments, stores or households. Regarding

[0002]

2. Description of the Related Art Foamed plastics are widely used for food trays, packing materials and the like because they are lightweight and have excellent heat insulating properties and shock absorbing properties. After being used, these foamed plastics are usually disposed of by landfill or incinerated, but it is desired to collect and recycle them from the viewpoint of reducing the amount of waste, energy saving and resource saving. However, the low bulk density gives rise to a factor of recovery and transportation cost, which makes it more expensive than virgin materials, making it difficult to be accepted in the market. In particular, for expanded polystyrene with a large amount of circulation, in order to reduce the recovery cost, a device that cuts and reduces the volume with a mechanical crushing and volume reducing device, a device that compresses mechanically, crushes mechanically and melts with friction heat The device etc. which do are developed. All of them have a large processing capacity, but since they are large-sized and expensive devices, they are not suitable for use in stores where a small amount of them are generated. On the other hand, as a method suitable for such a purpose, a method of heating the plastic at a low temperature and compressing it at a low pressure to reduce the volume has been proposed. This system has a simpler device configuration than the conventional one, and is suitable for a device for small processing. Therefore, a method of heating or compressing the foamed plastic at a low temperature by applying this method has been studied.

[0003]

In the heating or heat compression method capable of miniaturizing the apparatus, the foamed plastic is heated at a temperature as low as possible to suppress generation of decomposition gas from the foamed plastic as much as possible. However, since many foamed plastics use an organic foaming gas, gas is often generated by heating. In particular, a large amount of gas, such as butane or cyclohexane, remaining in the expanded polystyrene due to foaming is generated in the expanded polystyrene heat shrinking process regardless of the heating temperature. As a result, under the processing conditions, the generated gas is near the flammable limit concentration, and it becomes difficult to secure the safety of the equipment. In addition, since the material has excellent heat insulating properties, there is a problem that the amount of power consumption required for the heat treatment increases.

The present invention provides a volume-reducing device which solves the above problems in volume reduction of conventional foamed plastics, ensures safety during treatment, and saves energy during treatment. The purpose is to The present invention also heat-compresses and reduces the volume of foamed plastic that is generated in daily activities, thereby simplifying storage and improving collection efficiency and landfill efficiency at the time of disposal, especially for small-scale business sites, stores and It is an object of the present invention to provide an inexpensive and compact volume reduction device suitable for home use.

[0005]

A foamed plastic volume-reducing device of the present invention has a main body having a door, a foamed plastic housing provided inside the main body, a heating fan and a heater, and an outlet. And a catalyst provided with a hot air supply path that connects a suction port to the storage section and circulates hot air in the storage section, and an oxidation catalyst, and is provided in parallel with a part of the hot air circulation path including the hot air supply path. A deodorizing path is provided, and a part of hot air is configured to be supplied to the catalytic deodorizing path by utilizing the heating fan pressure of the hot air supplying path. A main body having a door, a foamed plastic storage section provided inside the main body, a heating fan and a heater, and hot air for circulating hot air in the storage section by connecting the air outlet and the suction port to the storage section Supply path, oxidation catalyst and catalyst And a catalyst deodorizing passage provided in parallel with a part of a hot air circulating passage including the hot air supplying passage, so that the catalyst fan supplies a part of the hot air to the catalyst deodorizing passage. It is composed.

Further, the foamed plastic volume-reducing device of the present invention has a main body having a door, a foamed plastic storage portion provided inside the main body, a heating fan and a heater, and a blow-out port and a suction port. A hot air supply path connected to the storage section for circulating hot air in the storage section, an air intake port provided in a negative pressure portion downstream in the flow direction of circulation of the hot air, and an oxidation catalyst, and an exhaust path downstream thereof. Is provided with a catalyst deodorizing passage opened to the outside through the hot air supply passage, and a part of the hot air is supplied to the catalyst deodorizing passage by utilizing the heating fan pressure of the hot air supply passage. . Further, in the foamed plastic volume-reducing device of the present invention, the catalyst deodorizing passage further has an opening in the hot air supply passage. further,
It has a bottom plate that moves up and down in the storage part, a bag provided between the bottom plate and the bottom of the storage part, and a compression means that includes a pump that sends air to the bag.

[0007]

The apparatus of the present invention having the above-mentioned structure can heat-expand the foamed plastic easily and safely to reduce the volume. In order to reduce the heat shrinkage and volume reduction of the foamed plastic, it is heated above the glass transition temperature, and in order to suppress the generation of gas during processing and to prevent sticking due to melting, the melting temperature is set to about 160 ° C as the upper limit. To do. In this treatment, the foamed plastic shrinks as the heating progresses, and as a result, organic foaming gas is generated. Especially,
During the processing of expanded polystyrene, a large amount of a foaming gas such as butane or cyclohexane, a foaming aid such as toluene or ethylbenzene, and a residual gas component such as styrene monomer are generated.

In the apparatus of the present invention, a heating fan pressure or a dedicated catalyst fan sequentially blows a portion of the hot air containing the gas component to the catalyst deodorizing passage to oxidize it, thereby lowering the gas concentration. At this time, the deodorized exhaust gas is returned to the hot air circulation path again, and the amount of heat generated when the gas components are oxidized is used to heat the foamed plastic. Further, in the structure in which the air intake port is provided in the negative pressure portion of the heating fan, the air required for combustion of the generated gas is taken in timely, and the oxidation reaction by the catalyst is optimized. Further, in this configuration, a hot air exhaust passage after passing through the catalyst deodorizing portion is provided in the hot air supply passage to recover heat of exhaust gas. Further, even in a configuration in which a part of the exhaust gas after the catalyst deodorizing section is returned to the hot air supply path and the rest is exhausted, the amount of heat obtained during the oxidation of the generated gas is used more positively for heating the sample. As described above, according to the present invention, it is possible to effectively reduce the gas generated when the foamed plastic is heated and ensure the safety of the volume reduction treatment. Further, by using the amount of heat generated during the gas treatment for heating the sample, it is possible to save energy in the treatment.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. [Embodiment 1] FIG. 1 is a longitudinal sectional view showing an embodiment of a volume reducing device according to the present invention. Reference numeral 1 denotes a main body, which has a cylindrical storage part 2 for storing the foamed plastic of the object to be processed, a hot air supply path for supplying hot air to the storage part 2, and the like. It has a door 3 that hermetically seals the upper opening. Inside the storage part 2, a bottom plate 4 that slides up and down on the inner wall thereof is provided, and an airtight bag 5 is provided. An air pump 6 is connected to the bag 5, and the bottom plate 4 can be raised by inflating the bag 5 with air pressure and lowered by evacuating the inside of the bag. A heat insulating container 7 is provided outside the storage portion 3, and a hot air supply passage 8 having a fan 9, a heater 10 and a temperature detecting portion 11 is provided on one side surface thereof. The hot air supply passage 8 has a hot air supply port connected to an opening 2a provided on the upper side surface of the storage unit 2, and an intake port is opened in the heat insulating container 7 in the vicinity of the opening 2b below the storage unit 2. . Further, a deodorizing passage 12 having a deodorizing portion 13 in parallel with the fan 9 is provided. The deodorizing unit 13 includes an oxidation catalyst, a heater 14 for heating the catalyst, and a temperature detecting unit 15.

Next, the operation will be described. First, the door 3 of the main body 1
Open and put foamed plastic in the storage part 2. next,
The heating fan 9 and the heating heater 10 are energized to open the opening 2
The hot air is blown downward from a so as to blow on the foamed plastic in the storage section 2. At this time, the hot air temperature detection unit 1
1, the hot air temperature is detected, and the input power of the heater is controlled so that the upper limit is 140 ° C. The blown hot air moves into the heat insulating container 7 through the opening 2b provided in the lower portion of the storage section 2. Then, it is sucked by the fan 9 and enters the hot air supply passage 8, where it is heated again and circulated. Further, a part of the air is sucked into the deodorizing passage 12 by the pressure of the fan 9, is oxidatively deodorized when passing through the catalyst deodorizing portion, and is returned to the hot air supply passage 8 again. After heating the foamed plastic in this way, the air pump 6 is operated to feed air into the bag 5, and the bottom plate 4 is raised to reduce the volume of the storage portion 2 to compress the foamed plastic. During a series of these operations, the pressure of the heating fan 9 is used to send a part of the generated gas to the deodorizing passage 12. At this time, the catalyst is heated by the catalyst heating heater 14 to a temperature at which the catalytic reaction can be maintained. The exhaust gas that has passed through the deodorizing unit is returned to the circulation path again.

In this example, expanded polystyrene was used as the expanded plastic to undergo thermal shrinkage and compression volume reduction. In this treatment, the expanded polystyrene needs to be heated above the glass transition temperature at which elasticity significantly decreases. But,
When heated above 200 ° C., odorous gas is decomposed or generated from the expanded polystyrene, or resin is dissolved, and workability tends to be deteriorated. In the present embodiment, the hot air temperature is detected by the temperature detection unit 11 provided at the hot air outlet, and the heating is controlled and controlled at 140 ° C. at which decomposition gas is not generated and resin is not melted. However, the expanded polystyrene undergoes thermal contraction with heating, and as a result, a large amount of a foaming gas such as butane or cyclohexane, a foaming aid gas such as toluene or ethylbenzene, and a residual gas component such as styrene monomer is generated. In particular, bead method expanded polystyrene is a material that generates a large amount of gas. In general, a foaming polystyrene material bead is impregnated with a foaming gas of about 7% of its own weight. These gases are released to the outside during the foam molding process, but some of them remain in the molded polystyrene foam. As a result, it is released by the heat shrinkage, and the device is filled.

Since these gas components are flammable gases, if they are circulated in the apparatus without being removed, there is a risk of catching fire with a heater or an electric spark. Furthermore, since most of these are odorous gases, if they are exhausted as they are, problems such as causing a bad odor occur. As an example, when expanded polystyrene is heated at 140 ° C. and filled in the apparatus, the gas generation amount is about 16 in terms of methane equivalent hydrocarbon concentration,
It became about 000 ppm. This gas concentration varies depending on the type of expanded polystyrene sample, and may be even higher. In addition, since the concentration of styrene, which is a malodorous substance, is about 600 ppm, the configuration that simply exhausts gas causes malodorous substances.

In the present embodiment, in order to solve the above problems, a hot air containing odorous gas is blown to the catalyst deodorizing portion utilizing the oxidation reaction at a heating fan pressure.
That is, the gas component generated when the expanded polystyrene is heated is blown to the catalyst deodorizing section at any time to oxidize the odorous gas with the catalyst,
The configuration is such that the gas concentration is reduced and odor is eliminated. As a result, it was possible to keep the hydrocarbon concentration of the gas in the apparatus at 1,000 ppm or less even when the maximum gas was generated. Also, the styrene concentration that causes a bad odor,
After passing through the catalyst deodorizing section, the generation of odor was reduced to 0.1 ppm or less. Furthermore, a large amount of heat of oxidation is generated during the oxidation of these odorous components. In fact, the generated gas in this example has a calorific value equivalent to that of the kerosene component. Further, since these gas components are generated in an amount of about 5 g in 5 minutes of heating, the amount of heat generated is about 600 kcal / h ^-1 . Therefore, the exhaust gas after passing through the catalyst has a high temperature of about 500 ° C.

In this embodiment, the exhaust gas is returned to the hot air circulation path. That is, the amount of heat generated when the gas component is oxidized is positively used for heating the expanded polystyrene. Actually, compared with the configuration in which the exhaust gas after passing through the catalyst deodorizing section is directly discharged, in the configuration in which the exhaust gas is returned to the circulation path, the power consumption is about
It could be reduced by about 0%. Further, the heat generated by the generated gas causes the temperature of the catalyst itself to maintain the reaction activity, so that the catalyst heating heater can be used only at the initial stage of the treatment. As described above, in the present embodiment, the gas generated during the heating of expanded polystyrene is optionally oxidized and removed by the catalyst deodorizing section, so that the gas concentration in the apparatus can be kept low, the odor can be reduced, and the heat of reaction can be used for heating the sample. It has been made possible to save energy in processing.

Although the treatment of foamed polystyrene, which generates a particularly large amount of gas, has been described as an example of the treatment, it may be foamed plastic using an organic foamed gas such as foamed polypropylene, foamed polyethylene, foamed ethylene-vinyl acetate copolymer resin or the like. In this case, the effects shown in this embodiment can be obtained. Further, although the heating temperature is 140 ° C. in the examples, it may be arbitrarily set within the range of 100 ° C. of the glass transition temperature to 160 ° C. of the melting temperature. Further, although the heating temperature is controlled by using the temperature detection unit, this control unit is not necessary when a heating heater whose input electric energy changes with temperature is used. Although a platinum group-based oxidation catalyst is used in the deodorizing portion, a catalyst having an oxidation reactivity with an organic compound such as manganese oxide may be used. Moreover, although the volume is reduced to about 1/50 by compressing after heating using air pressure, the volume can be reduced from about 1/20 to about 1/30 only by heating. You can omit it.

In the embodiment, the catalyst deodorizing section is provided with a catalyst heating heater and a temperature detecting section so that the temperature of the catalyst is about 500.
Although the temperature is maintained at a high temperature of about 0 ° C. to improve the catalytic activity, the temperature detection unit may be omitted depending on the conditions such that the amount of gas generated from the expanded polystyrene is constant or dilute. Further, although the catalyst deodorizing unit is installed outside the heating unit, installing the catalyst deodorizing unit in the heating unit can prevent heat dissipation and simplify the structure. Further, in this configuration, the catalyst deodorizing portion is provided immediately after the heating heater, so that the catalyst heating heater can be eliminated. Further, a part of the circulating hot air is blown to the catalyst deodorizing section, but by optimizing the circulating amount of hot air and the SV value of the catalyst deodorizing section, all of the hot air passes through the catalyst deodorizing section. Good.

[Embodiment 2] FIG. 2 is a longitudinal sectional view of a volume reducing apparatus of this embodiment. The same components as those of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. The difference from the first embodiment is that a catalyst fan 16 is provided downstream of the deodorizing section 13 of the deodorizing passage 12. In the second embodiment, the first embodiment
Performs almost the same operation as above, and reduces the volume of expanded polystyrene. The difference is that in Example 1, the hot air containing the generated gas was blown to the catalyst deodorizing unit 13 by the pressure of the heating fan, but a dedicated catalyst fan 16 was used.

When the heating fan blows air to the catalyst deodorizing section, the structure of the apparatus becomes simple. However, the air flow rate changes depending on the amount and condition of the sample to be processed. For example, when the amount of the sample is large and the circulation path of the hot air becomes small, the pressure loss increases and the amount of air blown to the catalyst deodorizing portion of the heating fan decreases. As a result, the generated gas cannot be sufficiently purified. Or conversely, when the amount of air blown to the catalyst deodorizing section is increased, there may arise a problem that the catalyst temperature is lowered and sufficient catalyst reactivity cannot be obtained. If a dedicated catalyst fan is used as in this embodiment, the amount of air blown to the catalyst deodorizing section can be made constant and the catalyst purification performance can be improved. That is, S of the catalyst layer
Since the V value can be optimized and the catalyst temperature distribution can be made uniform at the device design stage, the generated gas purification performance can be stably obtained. Needless to say, as in the first embodiment, the exhaust gas after passing through the catalyst is returned to the hot air circulation path to save energy in the process.

[Embodiment 3] FIG. 3 is a vertical sectional view of a volume reducing apparatus of this embodiment. The difference from the first embodiment is that an air intake port 18 is provided in the lower part of the heat insulating container 7 which is a negative pressure portion of the heating fan pressure in the hot air circulation path.
2 is branched downstream of the fan 9 of the hot air supply passage 8, and the discharge passage 20 downstream of the deodorizing unit 13 is once opened to the outside through the hot air supply passage 8. Further, the heat exchange fins 17 are added to the portion of the discharge passage 20 located inside the hot air supply passage 8 to improve the heat recovery rate from the exhaust gas after passing through the catalyst. In Example 3, substantially the same operation as in Example 1 was performed to reduce the volume of expanded polystyrene. The difference is that the negative pressure of the heating fan pressure is used to suck the outside air from the air intake port 18 provided in the lower part of the heat insulating container 7, and the exhaust gas from the catalyst deodorizing unit is passed through the hot air supply passage. After that, the operation of exhausting is performed.

In this example, as shown in Example 1, the concentration of gas generated in the container during heating of expanded polystyrene is about 16,000 ppm in terms of methane. It was also confirmed that the value may be far higher than that depending on the type of sample and the heating condition. In the case of catalytically oxidizing the generated gas, oxygen corresponding to its concentration is required. Therefore, since the oxygen consumption increases as the concentration of the generated gas increases, oxygen deficiency occurs in the configuration that does not take in the outside air, and the purification performance of the generated gas deteriorates. For example,
In Examples 1 and 2 in which the outside air was not positively taken in, there was a tendency that the catalyst purifying property of the generated gas at the time of generating the high-concentration gas deteriorated. However, in this embodiment, since the outside air is always taken in and the generated gas is purified under the condition of sufficient oxygen, the generated gas can be almost deodorized at all times. Further, when the pressure is constant in the heating process, thermal expansion causes leakage from the device, which causes odor generation. However, in this embodiment, by providing an exhaust port for the odorless exhaust gas after passing through the catalyst deodorizing section, this is dealt with and the generation of odor due to leakage is prevented. Further, by passing the exhaust passage through the hot air supply passage, the heat of the exhaust gas after passing through the catalyst deodorizing portion is recovered, and the energy saving of the process is achieved as in the first embodiment. In this embodiment, the heating fan is used to blow air to the catalyst deodorizing portion, but the same effect can be obtained by using a dedicated catalyst fan similar to that used in the second embodiment. Further, the air intake port is provided in the heat insulating container as the negative pressure side of the fan, but any place such as the motor shaft of the fan may be used on the negative pressure side of the fan. For example, a space is provided between the fan motor and the fan case, and the motor shaft serves as an air intake port.

[Embodiment 4] FIG. 4 is a vertical sectional view of a volume reducing apparatus of this embodiment. The difference from the third embodiment is that a return port 19 opening to the hot air supply passage is provided in the exhaust passage after passing through the catalyst deodorizing portion. According to this configuration, the heat recovery efficiency is improved as compared with the configuration in which the heat quantity of the exhaust gas is recovered by heat exchange as in the third embodiment. Although it depends on the amount returned to the hot air supply passage, the heat recovery efficiency in this embodiment is improved by about 30% as compared with the third embodiment. Further, since the exhaust gas after passing through the catalyst deodorizing portion is partially discharged, leakage of odor from the device due to thermal expansion can be prevented.

[0022]

As described above, according to the volume reducing apparatus of the present invention, it is possible to effectively reduce the volume of plastic foam by heating it to the glass transition point temperature or higher, and then heat shrinking or compressing it. Further, the combustible gas and odorous gas generated when the foamed plastic is heated can be effectively and safely reduced by using the catalyst deodorizing section. Further, by reusing the amount of heat generated when the generated gas is removed by oxidation in the catalyst deodorizing section for heating the foamed plastic, energy saving of the treatment can be achieved. As described above, according to the present invention, it is possible to reduce the amount of foamed plastic, ensure safety during processing, reduce odor generation, simplify storage, and improve collection efficiency at landfill and landfill efficiency. .

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of a foamed plastic volume reducing device according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a foamed plastic volume-reducing device according to another embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view of a foamed plastic volume reducing device according to another embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view of a foamed plastic volume reducing device according to still another embodiment of the present invention.

[Explanation of symbols]

 1 Main Body 2 Storage Part 2a, 2b Opening 3 Door 4 Bottom Plate 5 Bag 6 Air Pump 7 Insulation Container 8 Hot Air Supply Path 9 Heating Fan 10 Heater 11 Temperature Detection Section 12 Deodorization Path 13 Catalyst Deodorization Section 14 Catalyst Heating Heater 15 Temperature Detection unit 16 Catalyst fan 17 Fin 18 Air intake port 19 Return port 20 Discharge path

Front page continuation (72) Inventor Jiro Suzuki, 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. A main body having a door, a storage part of foamed plastic provided inside the main body, a heating fan and a heater, and an outlet and a suction port are connected to the storage part to form a storage part. A hot air supply path for circulating hot air, and a catalyst deodorizing path having an oxidation catalyst and provided in parallel with a part of the hot air circulation path including the hot air supply path, and a heating fan for the hot air supply path. A foamed plastic volume-reducing device configured to supply a part of hot air to the catalyst deodorizing passage by using pressure. 2. A main body having a door, a storage part of foamed plastic provided inside the main body, a heating fan and a heater, and an outlet and a suction port are connected to the storage part to form a storage part. A hot air supply path for circulating hot air, and a catalyst deodorizing path having an oxidation catalyst and a catalyst fan and provided in parallel with a part of the hot air circulating path including the hot air supply path. The foamed plastic volume reducing device configured to supply a part of the hot air to the catalyst deodorizing passage. 3. A main body having a door, a storage part of foamed plastic provided inside the main body, a heating fan and a heater, and an outlet and a suction port are connected to the storage part to form a storage part. A hot air supply path for circulating hot air, an air intake provided in a negative pressure portion downstream in the flow direction of circulation of the hot air, and an oxidation catalyst, and a discharge path downstream thereof is opened to the outside through the hot air supply path. And a catalyst deodorizing passage, and a part of hot air is supplied to the catalytic deodorizing passage by utilizing a heating fan pressure of the hot air supply passage. 4. The foamed plastic volume reducing device according to claim 3, wherein the catalyst deodorizing passage further has an opening in the hot air supply passage. 5. A compressing means comprising a bottom plate which moves up and down in the storage part, a bag provided between the bottom plate and the bottom of the storage part, and a compression means which is a pump for sending air to the bag. Foamed plastic volume reduction device described in