JP2005131480A - Method and apparatus for recycling biodegradable waste - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To collectively treat food residue and a dust bag without fractionating them to recycle them as resources. <P>SOLUTION: Hydrolytic treatment 2 and drying treatment 3 are performed successively. In the hydrolytic treatment 2, biodegradable waste 1 put in a bag made of a biodegradable plastic is heated along with the bag by steam while stirred and mixed and the biodegradable plastic contained in the biodegradable waste 1 is hydrolyzed to be converted to low-molecular matter. In the drying treatment 3, the biodegradable waste 1 is dehydrated not only to be reduced in volume but also to be recycled as biodegradable waste resources. The biodegradable waste 1b containing the biodegradable plastic is recycled as compost and feed 4a and, if the material to be treated is composed only of the biodegradable plastic 1a, it is recycled as lactic acid being the raw material 4b of the biodegradable plastic. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a biodegradable waste recycling method and apparatus for recycling biodegradable plastics (bioplastics) and biodegradable waste containing food residues as resources.

  Raw garbage, so-called food waste, generated in large quantities from food manufacturing factories, restaurants, etc., is representative of biodegradable waste. These are composed of organic substances such as carbohydrates, proteins, fats, and lignin and a small amount of inorganic substances. Food waste generally has a high moisture content and is prone to spoilage, so it is difficult to recover energy by direct combustion, but in addition to weight reduction by heating, it is effective as feed, organic fertilizer, compost, etc. It can be recovered as a resource to be used.

  For example, when composting biodegradable waste, agricultural waste such as animal and vegetable residues, leftovers, rice husks, animal manure, sawdust, bark, and wastewater treatment sludge discharged from activated sludge wastewater facilities Is composted and returned to farmland. Composting does not require so much advanced technology as long as it is a raw material for composting, and can be easily realized by controlling moisture, temperature, oxygen, microbial nutrition, and pH, Hazardous substances, especially the inclusion of toxic heavy metals, is a major impediment to the composting reaction.

  Further, Patent Document 1 deals with the problem of odor generated during processing time and processing time when processing biodegradable waste.

  In Patent Document 1, it takes several months or more to compost branches and leaves by a deposition method such as field stacking, and the problem of environmental pollution arises due to the strong odor of decay. A decomposing process in which activated water inhabiting EM bacteria is added to the object to be processed, which is obtained by pulverizing the biodegradable waste in a granular or powder form, and the object to be decomposed in water is deposited and decomposed. Treatment of biodegradable waste by sequentially performing an initial water decomposition step for decomposing by EM bacteria while aeration and a supernatant liquid decomposition step for removing the supernatant liquid from this initial water decomposition step and decomposing by EM bacteria while aeration A method or biodegradable waste treatment plant is proposed.

  According to this method, except for the initial sedimentary decomposition in which the generation of rot odor is small, the entire process is performed in water, so that the rot odor hardly radiates into the air. Since decomposition in water is carried out with aeration, both aerobic bacteria and anaerobic bacteria work actively, and the treatment object is softened and uniformly stirred by aeration, so that the bacteria are treated. The effect that it becomes easy to land on an object and the decomposition of the object to be processed can proceed very quickly is emphasized.

  However, the problems associated with composting biodegradable waste are not limited to harmful substances and odors. When so-called food wastes are discarded from food manufacturing factories, restaurants, etc., they are usually dumped in plastics bags or plastic bags as garbage bags. It is a major obstacle to composting. This is not just a garbage bag. Plastics containers used for storing lunch boxes and food items are discarded as they are after use, so plastics in general, including garbage bags, trays, tableware, containers, etc. (hereinafter including these plastics) Is an obstacle to composting.

  That is, as a method of composting biodegradable waste, there are methods such as a stirrer non-attached type, a rotating cylindrical type, a fixed stirring shaft type, a moving stirring shaft type, etc. In the process of proceeding fermentation while stirring, plastics do not ferment in a short time like raw garbage, so when composting biodegradable waste, take out plastics from food residue (raw garbage), It is necessary to sort out the waste into the composting apparatus and feed only the food residue that is biodegradable waste.

  The sorting operation requires manpower and is unsanitary. However, recently, garbage bags made of biodegradable plastics have been used for garbage bags. Even if biodegradable plastics are naturally decomposed by bacteria, Degradation does not proceed at the same rate as fermentation of degradable waste, and many biodegradable plastics do not progress in nature in the absence of light or air. Even if biodegradable plastics are used for plastics including garbage bags, they must be removed when composting.

This is exactly the same not only for composting but also for feed. Plastics must also be removed when using biodegradable waste as feed. In addition, since the method of recycling plastics that have been removed is not currently established, it is usually landfilled, but the biodegradation reaction in the soil is very slow, so it is a disposal site until it returns to the soil. The problem of ensuring is not solved. Apart from this, there is a carbonization drying method that does not require separation, but once carbonized, it is not metabolized by living organisms, so resources cannot be reused by this method. In that sense, the carbonization treatment drying method does not contribute to the effective use of resources.
Regarding biodegradable waste treatment technology, for example, Patent Document 2 describes an example of heat treatment of garbage.

  The invention described in Patent Document 2 relates to a garbage drying apparatus, and weight and volume are reduced by the following procedure. That is, after draining raw garbage, it is put into a heating tank and heated with a heater while stirring and pulverizing. The garbage is heated to gradually evaporate moisture and reduce its weight and volume. The solid matter left after drying is taken out from the outlet formed in the heating tank and buried in the soil and recycled as raw material for fertilizer, or incinerated with general waste. Although the solids left after drying may be recycled as raw material for fertilizer, it is also planned to be incinerated together with general waste. There is no concept of actively collecting garbage as a resource, and it is not treated to reuse biodegradable waste as a resource.

Patent Publication 2002-136948 JP 2000-176419 A

  The problem to be solved is that even when biodegradable plastics are used in plastics, when food residues (plastic waste) contain plastics in composting or feed, This has to be removed, and a method for regenerating biodegradable plastic waste as a raw material has not been established.

  The most important feature of the present invention is that the biodegradable waste containing the biodegradable plastics is collectively processed without being separated and recycled into resources.

That is, in the biodegradable waste recycling method according to the present invention, the biodegradable waste recycling method includes hydrolysis and drying.
In the hydrolysis treatment, biodegradable plastics that are contained in the biodegradable waste and heated to a low molecular weight are hydrolyzed in the presence of moisture, while stirring and mixing the biodegradable waste. It is a process that decomposes and lowers the molecular weight,
The drying process is a process of dehydrating and reducing the biodegradable waste.

  The hydrolysis treatment and the drying treatment are a series of treatments in which the biodegradable waste is further dehydrated after being heated and circulated while stirring the biodegradable waste in the same treatment chamber. It is performed continuously.

  Moreover, a hydrolysis process is a process which heats a biodegradable plastics on the temperature conditions exceeding 100 degreeC.

  The biodegradable waste is composed only of biodegradable plastics and regenerates low-molecular compounds that are raw materials for biodegradable plastics by hydrolysis and drying.

  Biodegradable waste includes food residues and food containers or bags made only of biodegradable plastics, hydrolyzed in a time of several tens of minutes to several hours, and further dried. Thus, the container or bag and the container or bag and the food residue are collectively processed without being separated and regenerated into resources such as fertilizer and feed.

  Also, heat treatment is performed under a temperature condition that does not exceed 150 ° C at which the biodegradable plastics exceed 100 ° C where the biodegradable plastics hydrolyze, and the biodegradable plastics melt and the food residue does not cause excessive carbonization. It is.

  Moreover, the odorous substance contained in the drain water produced | generated in the process of a hydrolysis and a drying process is detoxified by oxidizing and decomposing | disassembling with the functional water produced | generated by electrolysis.

  In addition, odorous substances that move to the gas phase during the drying process, flammable substances typified by hydrocarbons, and hydrogen by-produced by electrolysis are completely decomposed and rendered harmless in the presence of a catalyst.

The biodegradable waste recycling apparatus according to the present invention is a biodegradable waste recycling apparatus having a processing chamber, a steam pipe, a heat exchanger, and a pressure pump.
The processing chamber is a tank that performs a hydrolysis process and a drying process of biodegradable waste, and has an input port and an exhaust port, and inside the biodegradable waste that has been input into the tank Equipped with stirring blades for stirring and crushing
In the hydrolysis treatment, biodegradable plastics that are contained in the biodegradable waste and heated to a low molecular weight are hydrolyzed in the presence of moisture, while stirring and mixing the biodegradable waste. It is a process that decomposes and lowers the molecular weight,
Drying is a process of dehydrating and reducing biodegradable waste,
The steam pipe is a circulation line that connects the steam inlet of the processing chamber and the upper steam outlet, and a heat exchanger is connected in the pipe, and the circulation / circulation is in the pipe on the steam outlet side. A pressurizing pump is connected, and there is a bypass pipe in parallel with the pipe leading to the heat exchanger, and the pipe line of the steam pipe leading to the heat exchanger and the bypass pipe can be switched by an open / close valve. And
The heat exchanger is a temperature controller that heats or cools the air and steam in the steam pipe,
The pressurizing pump forcibly circulates water vapor between the processing chamber and the steam pipe while pressurizing the processing chamber.

Moreover, it further has an electrode electrolysis apparatus and a catalytic oxidation apparatus,
An electrode electrolysis device is a device that detoxifies the odorous substances contained in the drain water generated in the steam pipe during the hydrolysis and drying process by oxidizing and decomposing with functional water generated by electrolysis. ,
The catalytic oxidizer is an odorous substance that is generated in the steam pipe during the drying process and moves from the vapor to the gas phase, a flammable substance typified by hydrocarbons, and hydrogen by-produced by electrolysis in the presence of the catalyst. It is completely decomposed, rendered harmless and released into the atmosphere.

  In the invention described in Patent Document 2, a gas containing water vapor generated by heating garbage is sucked from a heating tank and condensed by a condenser to be separated into a gas and a liquid, and the gas is heated again. In the present invention, this water vapor is used for the hydrolysis reaction of the biodegradable plastics.

That is, the biodegradable waste recycling method according to the present invention is included in the biodegradable waste 1 by performing a hydrolysis treatment while stirring and mixing the biodegradable waste 1 as shown in FIG. The polylactic acid (C ₃ H ₄ O ₂ ) n, which is the main component of the biodegradable plastics 1a, is hydrolyzed to lactic acid (C ₃ H ₆ O ₃ ).

  In the method of the present invention, if the biodegradable waste 1 is a mixture of the food residue 1b and the biodegradable plastics 1a, the biodegradable plastics 1a can be converted into other food residues 1b by hydrolysis treatment 2. It is uniformly mixed with the biodegradable waste, and the dried product 3 regenerates the treated product into compost material and feed material 4a as resources. Therefore, when processing biodegradable waste such as food residue contained in a biodegradable plastics garbage bag, it is not necessary to separate the bag from the food residue as the contents. Similarly, when biodegradable plastics are used in plastics including trays, tableware, containers, etc., it is not necessary to remove the plastics from food residues.

  Further, if the biodegradable waste 1 to be treated is only the biodegradable plastics 1a, after the drying process, the treated product becomes lactic acid which is a degradable plastics raw material 4b, and biodegradable using this lactic acid as a raw material. Since plastics can be recycled, a preferred closed cycle is achieved.

  Embodiments of the biodegradable waste recycling method according to the present invention will be described below with reference to the drawings. FIG. 2 shows the structure of a biodegradable waste treatment apparatus used in the method of the present invention. In FIG. 2, the biodegradable waste processing apparatus includes a processing chamber 5, an exhaust pipe 9, a heat exchanger 6, a circulation / pressure pump 13, a catalytic oxidation apparatus 7, and an electrode electrolysis apparatus 8. It consists of a combination.

  The processing chamber 5 and the heat exchanger 6 are connected by a steam pipe 9. The steam pipe 9 is a circulation pipe that connects a steam inlet 10 at the lower part of the processing chamber 5 and an upper steam outlet 11. A heat exchanger 6 is connected in the pipe, and an upper steam outlet 11 is connected to the steam pipe 9. A circulation / pressurization pump 13 is connected in the side pipe line. Further, a bypass pipe 14 is connected to the steam pipe 9 in parallel with the pipe leading to the heat exchanger 6, and the pipe of the steam pipe 9 leading to the heat exchanger 6 and the bypass pipe 14 are opened and closed by valves 15, 15. The pipeline is switched.

  The treatment chamber 5 is a tank that performs the hydrolysis treatment 2 and the drying treatment 3 of the biodegradable waste 1 as shown in FIG. 1, and has a loading port 5 a and a discharge port 5 b. It is equipped with a stirring blade 16 that stirs and pulverizes biodegradable waste introduced into the tank while rotating about a vertical axis. The heat exchanger 6 is a temperature controller that heats or cools the air (steam) in the steam pipe 9, and the circulation / pressure pump 13 continuously pressurizes and heats the inside of the processing chamber 5, The inside of the processing chamber 5 and the steam pipe 9 are forcibly circulated. The catalytic oxidation apparatus 7 coexists with an odorous substance generated in the steam pipe 9 during the drying process and transferred from the vapor to the gas phase, a flammable substance typified by hydrocarbons, and hydrogen by-produced by electrolysis. This is a device that is completely decomposed and detoxified below and released into the atmosphere, and is connected to the upstream pipe line of the heat exchanger 6 and a drain tank 17 described later by an odor removing pipe 12.

  The electrode electrolysis device 8 is rendered harmless by oxidizing and decomposing odorous substances contained in the drain water generated in the steam pipe 9 in the course of hydrolysis and drying treatment with functional water generated by electrolysis. The drain tank 17 is installed in the drain tank 17, and the drain tank 17 is connected to the processing chamber 5, the upstream pipe line of the heat exchanger 6, and the inlet pipe line of the catalytic oxidation apparatus 7, respectively. And a drain pipe 19 for discharging the drain to the sewage.

  Next, a method for treating biodegradable waste according to the present invention using the above biodegradable waste treatment apparatus will be described. In this embodiment, the treatment object is a food residue, animal / plant residue, beverage Biodegradable plastic bags or containers containing these and water (plastics made of biodegradable plastics), but the types of biodegradable waste to be treated are limited However, in the present invention, the treatment of biodegradable plastics or biodegradable waste containing biodegradable plastics is a problem.

  Used biodegradable plastic bags and containers as well as food residues, drinking water, animal and plant residues are biodegradable waste. Hereinafter, the processing procedure will be described in accordance with the flow shown in FIG.

(1) Steam heating step S1
An object to be treated, that is, a food residue, drinking water or other biodegradable waste still contained in a bag or container is put into the processing chamber 5 together with the bag or container, and the stirring blade 16 is driven to rotate. Then, the workpiece is stirred and pulverized. As a result, the bag containing the object to be processed is broken, the containers are destroyed, and are pulverized together with the object to be processed in the bag and the container, and stirred and mixed.

  The heat exchanger 6 is set to the heating side and is started, and the circulation / pressure pump 13 in the steam pipe 9 is started, and the air in the processing chamber 5 is supplied to the pipe line 9 including the processing chamber 5 and the heat exchanger 6. The air in the steam pipe 9 is heated by the heat generated in the heat exchanger 12 and the hot air is sent into the processing chamber 5. In the processing chamber 5, the object to be processed is heated by the blown hot air, the water contained in the object to be processed evaporates, and the air containing the water vapor circulates between the steam pipe 9 and the processing chamber 5. The water vapor flowing in the steam pipe 9 is heated, the heated water vapor is blown into the processing chamber 5, and the object to be processed in the processing chamber 5 is heated by the heat of the blown water vapor.

  When the inside of the processing chamber 5 is heated to a certain temperature, the on-off valve 15 is switched to shut off the heat exchanger 6 and the pipe line between the processing chamber 5, and the bypass pipe 14 is communicated with the processing chamber 5. By driving 13, the object to be processed is heated by the heat of the water vapor while continuing to pressurize and heat the inside of the processing chamber 5 and circulate the water vapor in the processing chamber 5. Excessive heating of the object to be processed in the processing chamber 5 causes carbonization and oxidation, which is not preferable for using the object to be processed as a resource.

  In the present invention, the reason why the steam is heated by the heat generated in the heat exchanger 6 and the workpiece is indirectly heated using the heat of the steam as a heat source is to prevent the workpiece from being carbonized and oxidized. It is very convenient to heat the workpiece in the processing chamber 5 evenly. If, for example, an electric heater is used to heat the object to be processed, the object that is locally exposed to high temperature and directly exposed to the electric heater is heated to several hundred degrees Celsius, carbonized, oxidized, and reused as a resource. Difficult to do.

(2) Hydrolysis treatment step S2
The hydrolysis reaction of the biodegradable plastics contained in the biodegradable waste is naturally carried out according to the following formula (1) by bringing the biodegradable plastics into contact with water vapor under a certain pressure and temperature condition. The polylactic acid that progresses and is the main component of the biodegradable plastics is decomposed into lactic acid.
HO— (C ₃ H ₄ O ₂ ) n—H + (n−1) H ₂ O → n (C ₃ H ₆ O ₃ ) (1)
Polylactic acid is melted at a temperature of 100 ° C. or higher at which biodegradable plastics are hydrolyzed and at a temperature not exceeding 150 ° C. at which the biodegradable plastics are melted and the food residue does not cause excessive carbonization. Do. In order to decompose polylactic acid into lactic acid, it is desirable that the temperature be close to the melting temperature of polylactic acid. However, heating to a temperature close to 150 ° C. may result in enormous energy consumption and carbonization of polylactic acid. . FIG. 4 shows the results of examining the degree of deterioration due to temperature for each type of biodegradable plastics.

  FIG. 4 shows that a 4 mm thick plate made of biodegradable plastics (PLA), a 0.25 mm thick garbage bag, a 0.25 mm thick case, and a 0.20 m thick cup are placed at 100 ° C. It shows the degree of deterioration when steam heating is performed at 150 ° C. for 2 hours. Further, for reference, an example of steam heating treatment at 120 ° C. for 20 minutes is also shown. In FIG. 4, “does not break when pushed with a nail” or “does not break when pushed with a nail” means that there is no deterioration. In this state, hydrolysis does not proceed.

  With the exception of the 4mm thick PLA plate, all other biodegradable plastics deteriorated into a “cracked by claw” or “cleaved by claw” condition by heating at 120 ° C. for 2 hours, and hydrolyzed. It was found that progress is possible. That is, as long as it is processed into a sheet or film having a thickness of 0.25 mm or less, hydrolysis is possible by heating at 120 ° C. for 2 hours.

  In addition, it was found that hydrolysis progressed by heating at 140 ° C. for 2 hours on a 4 mm thick plate, but at 150 ° C. for 2 hours heating, it was melted and reused except in a case of 0.25 mm thickness. It was found that the biodegradable plastics deteriorated due to solidification. In addition, it turned out that hydrolysis progresses about a garbage bag by heating at 120 degreeC for 20 minutes, However, it turned out that none of other biodegradable plastics leads to hydrolysis. From the results shown in FIG. 4, it can be said that in order to promote the hydrolysis of biodegradable plastics for recycling, it is desirable to perform a heat treatment at a heating temperature of 120 ° C. to 140 ° C. for 2 hours by steam heating. Can do. The hydrolysis treatment and the drying treatment are usually tens of minutes to several hours and do not require more than one day.

(3) Water vapor discharge step S3
A water vapor discharge step is performed in anticipation of the hydrolysis reaction of the biodegradable plastics contained in the biodegradable waste. In the water vapor discharge step, the heat exchanger 6 is switched to the cooling side, the bypass pipe 14 is closed, the air containing the water vapor in the processing chamber 5 is sent to the heat exchanger 12, the water vapor is condensed, and the air in the processing chamber 5 is condensed. Gradually lower the temperature.

(4) Drying, cooling and unloading steps (S4, S5, S6)
Through the water vapor discharge step, the circulating air is dried, and the object to be processed in the processing chamber 5 is dried (S4), and the amount is reduced and reduced. Subsequently, stirring and mixing are continued and pulverized, and after waiting for the temperature to drop (S5), the object to be processed is taken out from the processing chamber (S5). The biodegradable plastics garbage bag no longer remains in the taken-out processed object, and is mixed with food residue and taken out as a granular or powdery processed product (S6). Becomes raw material for fertilizer and feed.

(5) Water vapor condensation, electrolysis, drainage step (S7, S8, S9)
In the steam discharge step S3, the water vapor is condensed, and the condensed liquid is collected from the processing chamber 5 and the steam pipe 7 into the drain tank 17 (S7) and generated in the electrode electrolyzer 8 in the drain tank 17. It is decomposed by hydroxy radicals (S8), the odor component in the liquid is removed (S9), and discharged into the sewage from the drain pipe 19.

(6) Catalytic oxidation and exhaust step (S10, S11)
The catalytic oxidation step S10 is a step of removing the odor in the air from which the liquid has been removed by the water vapor condensation step S7. The air in the steam pipe 9 is collected in the catalytic oxidation device 7, the odor component contained in the air is absorbed in the catalyst (S10), and the air from which the odor is removed is discharged into the atmosphere as exhaust (S11). The

  In the embodiment described above, food residues, for example, raw garbage discharged from the home are contained in biodegradable plastics garbage bags, and then subjected to hydrolysis treatment and drying treatment in order to produce compost and feed materials. An example of reproducing is described. However, the present invention is not limited to the case of processing food residues that are still stored in the garbage bags.

  For example, products sold at convenience stores and hamburger stores contain foods and beverages in disposable containers and dishes, or sell them in a package, and collected containers and dishes contain food residues. There are many cases where food is stored and discarded, such as unsold lunches.

  As long as these containers and tableware are made of biodegradable plastics, hydrolysis and drying are performed in exactly the same way as garbage bags without separating containers and tableware from food residues. It can be regenerated into compost and feed ingredients in sequence. In addition, it is not particularly polluted by containers and other items collected after use as a defective product in food factories, such as garbage bags and containers made of biodegradable plastics, and food containers. If it is made of degradable plastics, only a recovered product is subjected to hydrolysis and drying in order, so that a low molecular weight biodegradable plastic that becomes a raw material for biodegradable plastics from the treated product And biodegradable plastics can be regenerated using the recovered low molecular weight biodegradable plastics and lactic acid as raw materials.

  In addition, we use biodegradable plastic containers for tableware that is generated in large amounts by daily operations, such as in-flight meal dishes provided on an aircraft. It becomes possible to recycle the raw material.

  As mentioned above, although the example which hydrolyzed biodegradable plastics by water vapor | steam heating was demonstrated in the Example, in addition to water vapor | steam heating, the boiling point fall (evaporation point fall) by pressure reduction can also be combined. . The evaporation point of water is 80 ° C. under normal pressure, but the evaporation point of water can be lowered to 60 ° C. at a vacuum degree of about 40 torr, and the heat of water vapor is applied to biodegradable plastics at a lower temperature. Can act.

  As described above, the present invention is a biodegradable waste recycling method for performing a hydrolysis process and a drying process on a biodegradable waste and regenerating the treated product as a resource, and an apparatus for realizing this method. Even when biodegradable waste is mixed with food residues and biodegradable plastics, such as garbage stored in garbage bags, it can be processed in a batch without separating them. Thus, it can be regenerated as a raw material for fertilizer and feed, and the separation process is not required for the regenerating process, so that the number of processes can be greatly reduced, and it is hygienic.

  Further, the hydrolysis treatment and the drying treatment can be performed for several tens of minutes to several hours, and the treatment time can be greatly shortened as compared with the conventional method.

  Not only can food residues and bags or containers that contain them be separated and recycled into resources, but if biodegradable plastics are selected as biodegradable waste, In order to realize a closed cycle of resources, it is truly desirable that even used containers can be recycled again as raw materials for biodegradable plastics.

It is a figure which shows the point which enforces the method of this invention. It is a figure which shows an example of the apparatus which implements the method of this invention. It is a flowchart which implements the method of the present invention. It is a table | surface which shows the result of having investigated the degree of degradation by temperature for every kind of biodegradable plastics.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Biodegradable waste 2 Hydrolysis process 3 Drying process 4a Fertilizer, feed 4b Biodegradable plastics raw material 5 Processing chamber 6 Heat exchanger 7 Catalytic oxidation apparatus 8 Electrode electrolysis apparatus 9 Steam pipe 10 Steam inlet 11 Steam outlet 12 Odor removal pipe 13 Circulation / pressurization pump 14 Bypass pipe 15 On-off valve 16 Agitating blade 17 Drain tank 18 Drain pipe 19 Drain pipe

Claims (10)

A method for recycling biodegradable waste having hydrolysis treatment and drying treatment,
In the hydrolysis treatment, biodegradable plastics that are contained in the biodegradable waste and heated to a low molecular weight are hydrolyzed in the presence of moisture, while stirring and mixing the biodegradable waste. It is a process that decomposes and lowers the molecular weight,
A method for recycling biodegradable waste, characterized in that the drying process is a process of dehydrating and reducing the biodegradable waste. Hydrolysis treatment and drying treatment are a series of treatments in which the biodegradable waste is dehydrated after being continuously hydrolyzed by circulating heated steam while stirring the biodegradable waste in the same treatment chamber. The method for recycling biodegradable waste according to claim 1, wherein the method is performed. The method for recycling biodegradable waste according to claim 1, wherein the hydrolysis treatment is a treatment of heating the biodegradable plastics under a temperature condition exceeding 100 ° C. The biodegradable waste is composed only of biodegradable plastics, and the low molecular weight compound that is a raw material of the biodegradable plastics is regenerated by hydrolysis and drying. Recycling method of biodegradable waste. Biodegradable waste includes food residues and food containers or bags made only of biodegradable plastics, hydrolyzed in a time of several tens of minutes to several hours, and further dried. The biodegradable waste according to claim 1, wherein the biodegradable waste is a process in which the container or bag and the container or bag and the food residue are collectively processed without being separated and are recycled into resources such as fertilizer and feed. Recycling method. The hydrolysis treatment is performed under a temperature condition that does not exceed 150 ° C. at which the biodegradable plastics are hydrolyzed and that the biodegradable plastics melt and the food residue does not cause excessive carbonization. The biodegradable waste recycling method according to claim 1, wherein the biodegradable waste is recycled. The odorous substance contained in the drain water generated in the course of the hydrolysis treatment and the drying treatment is rendered harmless by oxidizing and decomposing with functional water generated by electrolysis. Recycling method of biodegradable waste. The odorous substance that moves to the gas phase during the drying process, the flammable substance typified by hydrocarbons, and the hydrogen produced as a by-product by electrolysis are completely decomposed and rendered harmless in the presence of a catalyst. Recycling method of biodegradable waste described in 1. A biodegradable waste recycling apparatus having a processing chamber, a steam pipe, a heat exchanger, and a pressure pump,
The processing chamber is a tank that performs a hydrolysis process and a drying process of biodegradable waste, and has an input port and an exhaust port, and inside the biodegradable waste that has been input into the tank Equipped with stirring blades for stirring and crushing
In the hydrolysis treatment, biodegradable plastics that are contained in the biodegradable waste and heated to a low molecular weight are hydrolyzed in the presence of moisture, while stirring and mixing the biodegradable waste. It is a process that decomposes and lowers the molecular weight,
Drying is a process of dehydrating and reducing biodegradable waste,
The steam pipe is a circulation line that connects the steam inlet of the processing chamber and the upper steam outlet, and a heat exchanger is connected in the pipe, and the circulation / circulation is in the pipe on the steam outlet side. A pressurizing pump is connected, and there is a bypass pipe in parallel with the pipe leading to the heat exchanger, and the pipe line of the steam pipe leading to the heat exchanger and the bypass pipe can be switched by an open / close valve. And
The heat exchanger is a temperature controller that heats or cools the air and steam in the steam pipe,
The recycling / pressurizing pump is a biodegradable waste recycling apparatus characterized in that water vapor is forcedly circulated between the processing chamber and the steam pipe while pressurizing the processing chamber. An electrode electrolysis device, and a catalytic oxidation device;
An electrode electrolysis device is a device that detoxifies the odorous substances contained in the drain water generated in the steam pipe during the hydrolysis and drying processes by oxidizing and decomposing with functional water generated by electrolysis. Yes,
The catalytic oxidizer is an odorous substance that is generated in the steam pipe during the drying process and moves from the vapor to the gas phase, a flammable substance typified by hydrocarbons, and hydrogen by-produced by electrolysis in the presence of the catalyst. The biodegradable waste recycling apparatus according to claim 9, wherein the biodegradable waste recycling apparatus is a device that completely decomposes, renders it harmless, and discharges it into the atmosphere.

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