Method for carbonizing pyrolysis residue of organic polymer material

Abstract

To provide a method capable of producing a high-quality residue carbonized material with less odor from the residue carbonized material generated by chemical recycling of plastic, rubber, and wood-based waste.SOLUTION: The present invention comprises thermally decomposing a material to be pyrolyzed such as plastic, rubber, and wood-based material to separate oil products and decomposition gases, and then heat-treating the residue remaining in the heat treatment furnace under reduced pressure or in an inert gas atmosphere at a temperature range of 350°C or higher and 1100°C or lower for 30 minutes or longer and 80 minutes or shorter. This allows for the removal of oil products adhering to the residue, resulting in less odor, and also removes oxygen and hydrogen contained in the chemical structure of the residue, enabling conversion to a high-quality carbonized material with low oxygen / carbon and hydrogen / carbon ratios. The residue obtained after such heat treatment can be recycled as a high-calorific solid fuel or carbon material.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for obtaining a carbonized material from the residue remaining after separating oily products and decomposition product gases from organic polymeric materials such as resins, rubbers, and woody materials. [Background technology]

[0002] Traditionally, plastic, rubber, and wood waste (hereinafter referred to as plastic waste, rubber waste, and wood waste) have mainly been disposed of by incineration or landfill. However, incineration presents challenges, such as the consumption of large amounts of fossil fuels, the generation of various toxic substances such as dioxins due to incomplete combustion, and the deterioration of incinerators due to the generation of corrosive gases. Even when disposed of in landfills, plastic waste and rubber waste in particular remain in the soil for long periods of time, causing soil pollution, and the fragmented plastic and rubber waste flows into oceans and rivers, disrupting ecosystems.

[0003] For this reason, technological development is being conducted to recycle plastic waste, rubber waste, and wood waste with the aim of reducing waste and fossil fuel consumption.The main recycling methods include material recycling, in which waste is washed, heated and melted, or compressed into pellets or flakes, which can then be reshaped; chemical recycling, in which oils obtained by thermal decomposition in a low-oxygen environment and gases produced by decomposition are used as fuel or raw materials for chemical products; and thermal recycling, in which waste is burned in the presence of air or oxygen, and the heat energy generated during the process is used.

[0004] Of these methods, chemical recycling has the advantages of being applicable to any organic polymeric material, such as plastic waste, rubber waste, and wood-based waste, of saving fossil fuels, and of being more effective at reducing carbon dioxide emissions than other recycling methods. Many reports of chemical recycling have been published that utilize the oils and decomposition gases obtained by pyrolysis of plastic waste, rubber waste, and wood-based waste. However, in reality, residues remain after the oils and decomposition gases are extracted from these organic polymeric materials (hereinafter referred to as "materials to be pyrolyzed").

[0005] There have been fewer studies on recycling this residue than on oils and decomposition gases, and currently it is often disposed of as industrial waste. This is thought to be because the residue is permeated with oils, has a strong fuel smell, and is difficult to handle, and also contains large amounts of oxygen and hydrogen, making it unusable as a carbon material or solid fuel.

[0006] For example, Patent Document 1 describes a method in which plastics are thermally decomposed to remove oily products and gases produced by decomposition, and then the remaining residue is heat-treated at 700°C or higher. The thermal decomposition of plastics is carried out in the presence of alkali, and the residue is washed with water before being heat-treated. By heat-treating the residue in this way, the carbon content can be increased, and it is expected that the residue will be used as a solid fuel such as briquettes or as a carbon material. Furthermore, the oily products contained in the residue are volatilized during the heat-treatment process, which also reduces the fuel odor of the residue. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 9-78070 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the method described in Patent Document 1 poses a significant risk of air being mixed into the pyrolysis tank during the thermal decomposition of the residue. If air is mixed into the thermal treatment furnace, the O / C ratio of the residue increases, resulting in a deterioration in its quality as a solid fuel or carbon material. Furthermore, the residue and the oily compounds contained in the residue react with oxygen to produce not only carbon dioxide but also oxygen-containing compounds with pungent odors, such as acetic acid and acetone. Furthermore, water is produced when the residue is burned. If this water is mixed into the oily compounds separated in the previous step of the thermal treatment of the residue, the quality of the oily compounds as a fuel or raw material for chemical products will also be reduced.

[0009] Therefore, in order to solve the above-mentioned problems, the present invention aims to provide a method for extracting oils, decomposition product gases, etc. from materials to be thermally decomposed, such as plastics, and continuously producing high-quality carbonized residue. [Means for solving the problem]

[0010] In the means 1 capable of achieving the above object, the following configuration is preferable. First, the material to be pyrolyzed is placed on the bottom of a heating container in the heat treatment furnace 1, and the inside of the heat treatment furnace is replaced with an inert gas. While the inert gas is being introduced, the container in the heat treatment furnace 1 is heated using a heat source, such as a heater 14, installed on the periphery of the heat treatment furnace. The heating is performed at a temperature range of 350°C to 600°C for a time period of 30 minutes to 90 minutes. The pyrolysis of the material to be pyrolyzed 3 is performed by this heating. This pyrolysis makes it possible to extract oily products and decomposition product gases. The oily products and decomposition product gases are removed from the outlets 4 and 6, leaving behind a residue 13. Thereafter, the residue 13 is further heat-treated at a temperature range of 500°C to 1100°C for 15 minutes to 80 minutes while continuously introducing the inert gas 12, thereby producing a high-quality carbide having an excellent oxygen-to-carbon mass ratio O / C and hydrogen-to-carbon mass ratio H / C.

[0011] According to the above-described production method, prior to thermally treating the pyrolysis target, the air in the heat treatment furnace is evacuated and replaced with an inert gas, suppressing oxygen-induced combustion within the heat treatment furnace. Further heating is performed to remove the oily products and decomposition product gases from the heat treatment target. The remaining residue is then heated in an inert atmosphere, enabling near-complete removal of the oily products and a high degree of removal of oxygen and hydrogen contained in the residue. This allows for the production of high-quality chars, e.g., chars with an oxygen-to-carbon ratio (O / C ratio) of less than 0.1 and a hydrogen-to-carbon ratio (H / C ratio) of less than 0.9, which are classified as bituminous or anthracite according to the coal band (Coal Technology Overview, edited by the Institute of Applied Energy, Electric Power Shimposha (1993), 35). [Effects of the Invention]

[0012] According to the present invention, it is possible to solve the above-mentioned problems and provide a method for extracting oils and decomposition product gases from materials to be thermally decomposed, such as plastics, and producing high-quality carbonized residue with low O / C and H / C ratios.

[0013] (Other means to solve the problem) Means 2 for achieving the object of the present invention will be described below. First, the thermal decomposition object 3 is placed on the bottom of a heating vessel in a heat treatment furnace 1, and the vessel is evacuated to remove the air from the heat treatment furnace 1. Following this air removal process, the thermal decomposition object 3 in the heat treatment furnace 1 is thermally decomposed at a temperature ranging from 350°C to 600°C for a period of 30 to 90 minutes while an inert gas 12 is introduced. This thermal decomposition allows the oily materials and decomposition product gases to be gradually released from the thermally decomposed material 3. After this thermal decomposition process, the thermally decomposed material 3 becomes a residue 13. Furthermore, the residue 13 is subjected to a heat treatment process at a temperature ranging from 500°C to 1100°C for a period of 15 to 80 minutes while an inert gas is introduced. As the residue 13 is carbonized, the oily materials and decomposition product gases are almost completely released, producing a carbonized residue. By satisfying these conditions, the method makes it possible to obtain a residue carbide having an oxygen to carbon mass ratio O / C of less than 0.1 and a hydrogen to carbon mass ratio H / C of less than 0.9 while carbonizing the residue 13 in the above-mentioned atmosphere.

[0014] Next, the third means for achieving the object of the present invention will be explained below. First, the thermal decomposition target 3 is placed on the bottom of a heating vessel in a heat treatment furnace 1, and the inside of the vessel is replaced with an inert gas. Following this inert gas replacement process, the thermal decomposition target 3 in the heat treatment furnace 1 is thermally decomposed at a temperature range of 350°C to 600°C for a time period of 30 to 90 minutes while an inert gas 12 is introduced. At the same time, the oily products and decomposition product gases are gradually discharged. After this thermal decomposition process, the residue of the thermal decomposition target is further subjected to a heat treatment process at a temperature range of 500°C to 1100°C for a time period of 15 to 80 minutes while evacuating the atmosphere. The residue 13 is carbonized, and the oily products and decomposition product gases are almost entirely discharged, producing a carbonized residue. By satisfying these conditions, the method makes it possible to obtain a residue carbide having an oxygen to carbon mass ratio O / C of less than 0.1 and a hydrogen to carbon mass ratio H / C of less than 0.9 while carbonizing the residue 13 in the above-mentioned atmosphere.

[0015] Next, the fourth means for achieving the object of the present invention will be explained below. First, the thermal decomposition target 3 is placed on the bottom of the heating vessel in the heat treatment furnace 1, and the vessel is evacuated to remove the air from the heat treatment furnace 1. Following this air removal process, the thermal decomposition target 3 in the heat treatment furnace 1 is thermally decomposed at a temperature range of 350°C to 600°C for 30 to 90 minutes while an inert gas 12 is introduced. At the same time, the oily products and decomposition product gases are gradually discharged. After this thermal decomposition process, the residue of the thermal decomposition target is further subjected to a heat treatment process at a temperature range of 500°C to 1100°C for 15 to 80 minutes while evacuating the vessel. The oily products and decomposition product gases are discharged while the residue 13 is carbonized, producing a carbonized residue. Even under these production conditions, it is possible to provide a production method that makes it possible to obtain a residue carbide having an oxygen to carbon mass ratio O / C of less than 0.1 and a hydrogen to carbon mass ratio H / C of less than 0.9 while carbonizing the residue 13 under the above-mentioned atmosphere.

[0016] In any of the above-mentioned methods 2 to 4, combustion by oxygen in the heat treatment furnace can be suppressed by creating an inert, oxygen-free atmosphere in the heat treatment furnace before heat-treating the pyrolysis target. Further heating can be performed to remove oily materials and decomposition product gases from the heat treatment target, while heating the remaining residue in an inert atmosphere. This allows for near-complete removal of oily materials and a high level of removal of oxygen and hydrogen contained in the residue. This allows for the production of high-quality chars, for example, chars with an O / C ratio of less than 0.1 and an H / C ratio of less than 0.9, which are classified as bituminous or anthracite according to the coal band (Coal Technology Overview, edited by the Institute of Applied Energy, Electric Power Shimposha (1993), 35).

[0017] According to the present invention, by making the heat treatment furnace oxygen-free before heat treating the material to be pyrolyzed, combustion of the material by oxygen in the heat treatment furnace can be suppressed, and oxidation of the residue can be prevented. Furthermore, after separating the oily material and decomposition product gases by pyrolysis of the material to be pyrolyzed, the residue can be heated while circulating in an oxygen-free atmosphere such as an inert gas in the heat treatment furnace, thereby removing the oily material remaining in the residue. Furthermore, by removing the oxygen and hydrogen contained in the residue, the residue can be converted into a high-quality charcoal of at least low-rank bituminous coal, which can be recycled as a solid fuel or carbon material with a high calorific value.

[0018] The plastics that are the targets of pyrolysis to produce the carbonized residues described above can fulfill the functions of the present invention as long as they are made of at least one of polyethylene, polypropylene, polystyrene, polycarbonate, acrylic resin, polylactic acid, polybutylene succinate, polyphenylene sulfide, nylon 6, nylon 66, polyimide, acrylonitrile-butadiene-styrene copolymer, natural rubber, acrylonitrile butadiene rubber, synthetic natural rubber, butadiene rubber, chloroprene rubber, silicone rubber, acrylic rubber, urethane rubber, wood, and pulp.

[0019] Furthermore, the inert gas in the present invention can fulfill the function of the present invention as long as it contains at least one of nitrogen, helium, argon, xenon, neon, krypton, and carbon dioxide. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a diagram showing a schematic diagram of a heat treatment device for obtaining oily products and decomposition product gases from a thermal decomposition target material. [Figure 2] FIG. 2 is a diagram schematically illustrating an apparatus for heat-treating a residue. [Figure 3] FIG. 1 is a diagram showing a schematic diagram of an apparatus for thermally treating a material to be thermally decomposed and separating oily products and gases produced by decomposition. [Figure 4] FIG. 2 is a diagram schematically illustrating a heat treatment device for carbonized residue. [Figure 5]FIG. 2 is a diagram schematically showing an example in which a cleaning process can be performed inside the heat treatment furnace 1. DETAILED DESCRIPTION OF THE INVENTION

[0021] The following describes embodiments of the present invention. The embodiments described below are examples of preferred embodiments of the invention, and do not limit the constituent elements of the present invention described in the claims.

[0022] (Types of plastics and rubbers that are subject to thermal decomposition) In the present invention, preferred plastic materials that can be heat treated include polyethylene, polypropylene, polystyrene, polycarbonate, acrylic resin, polylactic acid, polybutylene succinate, polyphenylene sulfide, nylon 6, nylon 66, polyimide, and acrylonitrile-butadiene-styrene copolymer.

[0023] On the other hand, rubber materials that can be thermally decomposed in the present invention preferably include natural rubber, acrylonitrile butadiene rubber, synthetic natural rubber, butadiene rubber, chloroprene rubber, silicone rubber, acrylic rubber, and urethane rubber.

[0024] (Wood-based material quality) In the present invention, wood-based materials that can be heat-treated include wood, pulp, and any other cellulosic materials.

[0025] (Material of heat treatment furnace 1) Materials for the heat treatment furnace 1, particularly the kiln, a container that can be heated to high temperatures, can be ceramic, quartz, stainless steel, heat-resistant steel, etc., but ceramic and heat-resistant steel are more preferred, with heat-resistant steel being the most preferred. This is because heat-resistant steel exhibits little loss in strength even when exposed to high temperatures for long periods of time during the carbonization process of plastic waste, waste rubber waste, and wood-based waste, and also has excellent impact resistance.

[0026] (Type of inert gas) The inert gas used in the heat treatment step of the pyrolysis object and the heat treatment step of the residue is preferably nitrogen, helium, argon, xenon, neon, krypton, or carbon dioxide, more preferably nitrogen, argon, or carbon dioxide, and most preferably nitrogen, because nitrogen can be supplied from a high-pressure gas cylinder or a nitrogen generator that separates nitrogen from air.

[0027] (Gauge pressure inside the heat treatment furnace 1 during the heat treatment process of the pyrolysis object and the heat treatment process of the residue) In the heat treatment process of the material to be pyrolyzed and the heat treatment process of the residue, the gauge pressure in the heat treatment furnace 1 is preferably 0.001 MPa.G or more and 0.1 MPa.G or less, more preferably 0.01 MPa.G or more and 0.05 MPa.G or less, and most preferably 0.015 MPa.G or more and 0.025 MPa.G or less. If the pressure in the heat treatment furnace is less than 0.001 MPa.G, there is a concern that air may easily flow into the heat treatment furnace 1, and if the pressure exceeds 0.1 MPa.G, measures to make the heat treatment furnace pressure-resistant will be necessary.

[0028] (Heat treatment process for pyrolysis object) The entire heat treatment apparatus of the present invention is shown schematically in Figure 3. The material to be pyrolyzed 3 is placed in heat treatment furnace 1 through lid 2, and after closing lid 2, valves 5 and 7 and pressure regulator 8 are closed. Valve 9 is then opened and the pressure inside heat treatment furnace 1 is reduced using vacuum pump 10. Valve 9 is then closed, pressure regulator 8 is opened, and inert gas is introduced into heat treatment furnace 1 from inert gas cylinder 12. At this time, the flow rate of the inert gas can be set as desired using mass flow controller 16.

[0029] When the pressure inside the heat treatment furnace 1 rises to atmospheric pressure, valve 5 is opened and the temperature inside the heat treatment furnace 1 is then increased by heater 14. At this time, the set temperature of heater 14 can be adjusted by temperature controller 18 via wiring 17. During heat treatment, the temperature inside the heat treatment furnace 1 is measured by thermocouples 19a to 19c, which are connected to temperature controller 17 via wiring 20. When the temperature inside the heat treatment furnace 1 reaches the set temperature of heater 14, the heat supply from heater 14 can be stopped.

[0030] The oily products and cracked product gases produced from the thermal decomposition object 3 are stored in an oily product storage tank 22 through a pipe 21 from an outlet 4. Therefore, oily products with various carbon numbers, from naphtha to heavy oil, can be stored in the oily product storage tank 22, but by heating and distilling with a heater 23, only the oily products whose volatilization temperature is lower than the distillation temperature can be separated and sent to an oily product storage tank 25 through a pipe 24.

[0031] The heater 23 is connected to the temperature controller 18 via wiring 26, and the supply of heat from the heater 23 to the oil storage tank 22 can be stopped when the temperature of the thermocouples 28a to 28c, which are also connected to the temperature controller 18 via wiring 27, reaches the set temperature of the heater 23.

[0032] Meanwhile, the inert gas and the gas produced by decomposition from the thermal decomposition object 3 can be introduced into the water tank 31 through piping 21, oiled product storage tank 22, piping 24, oiled product storage tank 25, piping 29, and valve 30. If the thermal decomposition object 3 contains nitrogen, sulfur, or chlorine, it is expected that ammonia, hydrogen sulfide, hydrogen chloride, nitrogen oxides, sulfur oxides, chloric acid, etc. will be produced, but these gas components dissolve in the water in the water tank 31, and therefore can be prevented from being released into the atmosphere from piping 32.

[0033] In addition, by using sodium hydroxide solution, potassium hydroxide solution, or hydrogen peroxide solution instead of water in the water tank 31 depending on the material to be thermally decomposed, the efficiency of removing the above-mentioned ammonia, hydrogen sulfide, hydrogen chloride, nitrogen oxides, sulfur oxides, and chlorine acid can be improved.

[0034] (Heat treatment temperature of the material to be pyrolyzed) The heat treatment temperature of the thermally decomposed material 3 is preferably 350°C or higher and 600°C or lower, more preferably 400°C or higher and 550°C or lower, and most preferably 450°C or higher and 530°C or lower. If the heat treatment temperature of the thermally decomposed material 3 is higher than 600°C, there is a concern that the yield of the oily product will decrease, and if it is lower than 350°C, there is a concern that the decomposition of the thermally decomposed material 3 will be insufficient and no oily product will be obtained.

[0035] (Heat treatment time of the object to be pyrolyzed) The heat treatment time for the thermal decomposition object 3 is preferably 30 to 120 minutes at a temperature of 400°C or less, more preferably 50 to 80 minutes, and most preferably 60 to 70 minutes. If the heat treatment time for the thermal decomposition object 3 is shorter than 30 minutes in this temperature range, there is a concern that the decomposition will be insufficient and no oily product will be obtained, and even if the heat treatment time is longer than 120 minutes, there will be almost no change in the yield of the oily product, making it of little industrial significance.

[0036] The heat treatment time for the thermal decomposition object 3 is preferably 15 to 90 minutes, more preferably 30 to 70 minutes, and most preferably 50 to 60 minutes, when the temperature is higher than 400°C and not higher than 600°C. If the heat treatment time for the thermal decomposition object 3 is shorter than 15 minutes in this temperature range, there is a concern that the decomposition will be insufficient and no oily product will be obtained, and even if the heat treatment time is longer than 90 minutes, there will be almost no change in the yield of the oily product, making it of little industrial significance.

[0037] (Amount of material to be pyrolyzed put into the heat treatment furnace) When the thermal decomposition object 3 is introduced into the heat treatment furnace 1, it is preferable that the bulk volume of the thermal decomposition object 3 and the volume of the heat treatment furnace 1 satisfy the following equation 1. M and V F represent the bulk volume of the pyrolysis object 3 and the volume of the heat treatment furnace 1, respectively.

[0038]

number

[0039] Regarding the bulk volume of the thermal decomposition object 3 and the volume of the heat treatment furnace 1, the value of 1 is preferably 0.70 or less, more preferably 0.60 or less, and most preferably 0.40 or less. This is because if the value of 1 is greater than 0.70, the thermal decomposition object 3 will expand due to heat, and there is a risk of leakage into the piping connected to the heat treatment furnace 1.

[0040] (Overview of the residue heat treatment process) After the thermal treatment process of the pyrolysis target 3, a residue 13 remains in the thermal treatment furnace 1. The main component of the residue 13 is carbon, and it can be used as a solid fuel or graphite, but as mentioned above, the residue 13 also contains a large amount of oily substances, making it difficult to use as is. For this reason, it is necessary to remove the oily substances from the residue 13.

[0041] When removing oil from residue 13, valves 5 and 30 are closed, valve 7 is opened, and heater 14 is heated to a predetermined temperature. As a result, the oil contained in residue 13 is stored in gas-liquid separation tank 33.

[0042] The gas components generated from the inert gas and residue 13 are introduced directly into the water tank 31 through the pipe 34, and if the gas components contain ammonia, hydrogen sulfide, hydrogen chloride, nitrogen oxides, sulfur oxides, or chloric acid, they are removed in the water tank 31 and then appropriately released from the pipe 32.

[0043] (Temperature during residue heat treatment) During the heat treatment of the residue 13, the set temperature of the heater 14 is preferably equal to or higher than the volatilization temperature of the oily substance, but in order to rapidly remove the oily substance, it is more preferable to set the temperature to a range equal to or higher than the heat treatment temperature of the pyrolysis target 3. Furthermore, the higher the heat treatment temperature of the residue 13, the easier it is to remove the oxygen and hydrogen contained in the residue 13, which reduces the H / C ratio and O / C ratio of the residue 13 and allows for the production of a carbonized product with higher added value. Furthermore, if the pyrolysis target 3 is a material used as a raw material for activated carbon, such as plant biomass or acrylic, activation treatment is also possible.

[0044] The set temperature of heater 14 when heat-treating residue 13 is preferably 500°C or higher and 1100°C or lower, more preferably 550°C or higher and 900°C or lower, and most preferably 600°C or higher and 900°C or lower. If the temperature when heat-treating residue 13 is higher than 1100°C, there is a concern that the heat treatment furnace may deteriorate, and if it is lower than 500°C, there is a concern that the oily substances may not be sufficiently removed.

[0045] (Residue heat treatment time) The heat treatment time for residue 13 is preferably 15 minutes to 80 minutes, more preferably 40 minutes to 70 minutes, and most preferably 55 minutes to 65 minutes. If the heat treatment time for residue 13 is shorter than 15 minutes in this temperature range, there is a concern that the oily substances will not be sufficiently removed and the H / C ratio and O / C ratio will not be sufficiently reduced. Furthermore, if the heat treatment time is longer than 80 minutes, there will be little change in the degree of oily substances removed and there will be little change in the H / C ratio and O / C ratio, which will make the heat treatment less industrially significant.

[0046] (Pressure inside the heat treatment furnace during residue heat treatment) The pressure inside the heat treatment furnace 1 when heat treating the residue 13 is preferably 0.001 MPa.G or more to 0.1 MPa.G or less, more preferably 0.01 MPa.G or more to 0.05 MPa.G or less, and most preferably 0.015 MPa.G or more to 0.025 MPa.G or less. If the pressure inside the heat treatment furnace is less than 0.001 MPa.G, there is a concern that air may easily flow into the heat treatment furnace 1, and if the pressure exceeds 0.1 MPa.G, measures to withstand the pressure of the heat treatment furnace will be necessary.

[0047] (Cleaning the inside of the heat treatment furnace after residual heat treatment) After heat treatment, residue 13 can be removed by opening lid 2, but it is difficult to completely remove fine residue remaining in heat treatment furnace 1 by brushing. Therefore, as shown in Figure 5, valves 5 and 9 and pressure regulator 8 are closed, and valves 7 and 35 are opened. Air is introduced into heat treatment furnace 1 from compressor 36 through piping 37 while heater 14 is used to maintain the temperature inside heat treatment furnace 1 at 500°C or higher, thereby burning off any remaining fine residue.

[0048] The following examples of the preferred thermal treatment process for the pyrolysis object and the thermal treatment process for the residue will be described in more detail. Note that the examples using experimental equipment are intended to explain the invention in detail and are not intended to limit the scope of the invention. Example 1

[0049] (Substances subject to thermal decomposition) The thermal decomposition material used in this example was acrylonitrile butadiene rubber, which was left in a dryer set at 80° C. for 12 hours before heat treatment.

[0050] (inert gas) In this example, nitrogen was used as the inert gas.

[0051] (Heat treatment of pyrolysis target) In this example, 25 kg of the material to be pyrolyzed was placed in heat treatment furnace 1 as shown in Figure 3, valves 7 and 9 were closed, and valve 5 and pressure regulator 8 were opened to introduce inert gas into heat treatment furnace 1. Valve 5 was then opened when the gauge pressure in heat treatment furnace 1 reached 0.02 MPa. At this time, the opening of valve 5 was adjusted to maintain the gauge pressure in heat treatment furnace 1 at 0.02 MPa, while the temperature was raised to 500°C and held for 60 minutes. This separated the oily material and the gas produced by the pyrolysis. In this example, the ratio of the bulk volume of the material to be pyrolyzed to the volume of the heat treatment furnace was 0.40 according to equation 1.

[0052] (Heat treatment of residue) When the residue was heat-treated, valve 5 shown in Fig. 4 was closed, valve 7 was opened, and the temperature inside the heat treatment furnace 1 was set to 700°C and maintained for 55 minutes. This allowed the residue 13 to be heat-treated while introducing an inert gas into the heat treatment furnace 1.

[0053] (Odor evaluation of residue after treatment) After the heat treatment of the residue 13, the lid 2 was opened and the residue after the heat treatment (hereinafter referred to as the residue after the heat treatment) was taken out, and its odor was evaluated based on the 5-point scale shown in Table 1. Note that when the odor index was 4 or higher, it was judged that the product could be used without any problems as a solid fuel or carbon material, and was therefore evaluated as "suitable."

[0054] [Table 1]

[0055] As a result, the odor evaluation of the post-heat treatment residue obtained in this example was 5, and was judged to be "suitable."

[0056] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured according to the chloroform-methanol mixed liquid extraction method described in the Analysis Manual for the Standard Tables of Food Composition in Japan, and the amount of oil contained in the residue after heat treatment was calculated using the formula shown in Equation 2 below.

[0057]

number

[0058] Here, R represents the percentage of oily matter contained in the residue (%), W0 represents the weight of the residue (g) before extraction with chloroform and methanol, and W represents the weight of the residue (g) after extraction with chloroform and methanol. When the oil content of the residue was less than 1%, it was determined that it could be used without any problems as a solid fuel or carbon material, and was therefore rated as "suitable." Furthermore, when the amount of oil contained in the residue after heat treatment was quantified using the above method, it was found to be 0.2%, and was therefore rated as "suitable."

[0059] (H / C ratio and O / C ratio of residue after heat treatment) The carbon, hydrogen, and oxygen contents of the heat-treated residue were quantified using an organic elemental analyzer (Elementar, UNICUBE). For carbon and hydrogen content determination, 2 mg of sample in a tin capsule was combusted in contact with tungsten oxide (Elementar, product number S11.02-0017) for 70 seconds while flowing helium at 200 ml / min and introducing oxygen at a flow rate of 28 ml / min. The carbon and hydrogen were converted to CO and HO, respectively, and the CO and HO were detected using a thermal conductivity detector (TCD). The sample combustion temperature was 1150°C. For oxygen content determination, 2 mg of sample in a silver capsule was heated to 1170°C while flowing helium at 200 ml / min in contact with carbon black (Elementar, product number S03 679 910). The resulting CO was detected using a TCD.

[0060] (Quality evaluation of carbide residue after heat treatment) The O / C and H / C ratios were calculated from the C, H, and O compositions of the heat treatment residue revealed by organic elemental analysis. Based on the coal band, the heat treatment residue was evaluated as "suitable" if it was judged to be a charcoal of the same or higher quality than low-rank bituminous coal.

[0061] In this example, if the O / C ratio of the post-heat treatment residue was less than 0.07 and the H / C ratio was less than 0.4, it was determined to be anthracite; if the O / C ratio was less than 0.1 and the H / C ratio was 0.4 to less than 0.9 or if the O / C ratio was 0.07 to less than 0.1 and the H / C ratio was less than 0.4, it was determined to be bituminous coal; if the O / C ratio was 0.1 to less than 0.2 and the H / C ratio was less than 0.9, it was determined to be subbituminous coal; and if the O / C ratio was 0.2 to less than 0.4 and the H / C ratio was less than 1.0, it was determined to be equivalent to peat.

[0062] Organic elemental analysis of the heat treatment residue obtained in this example revealed that the weight percentages of C, H, and O were 66.0, 1.4, and 5.9 wt.%, respectively, and the calculated H / C and O / C ratios were 0.255 and 0.067, respectively. Therefore, the heat treatment residue obtained in this example was classified as anthracite in the coal band, and the quality assessment of the heat treatment residue as a charcoal was judged to be "suitable."

[0063] (comprehensive evaluation) From the above results, both the odor evaluation of the residue after heat treatment and the quality evaluation as a carbonized product met the standards, and therefore the overall evaluation of this example was deemed appropriate. Example 2

[0064] (Substances subject to thermal decomposition) The pyrolysis target used in this example was acrylonitrile butadiene rubber. The pyrolysis target was placed in a dryer set at 80° C. for 12 hours before heat treatment.

[0065] (inert gas) In this example, nitrogen was used as the inert gas.

[0066] (Heat treatment of pyrolysis target) In this example, 30 kg of the material to be pyrolyzed was placed in the heat treatment furnace 1 as shown in FIG. 3 . Then, valves 5 and 7 and pressure regulator 8 were closed, and valve 9 was opened to evacuate the heat treatment furnace 1 using vacuum pump 10. Valve 9 was then closed, pressure regulator 8 was opened, and inert gas was introduced into the heat treatment furnace 1. When the gauge pressure reached 0.015 MPa, valve 5 was opened. At this time, the gauge pressure in the heat treatment furnace 1 was maintained at 0.015 MPa by adjusting the opening of valve 5, and the temperature was raised to 500°C and held for 60 minutes. This separated the oily product and the gas produced by the pyrolysis. In this example, the ratio of the bulk volume of the material to be pyrolyzed to the volume of the heat treatment furnace was 0.48 according to equation 1.

[0067] (Heat treatment of residue) After the heat treatment step of the object to be pyrolyzed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 800° C. and the heat treatment time was 60 minutes.

[0068] (Odor evaluation of residue after treatment) The odor of the residue after the heat treatment was evaluated on a 5-point scale shown in Table 1, and was given a score of 5, ie, "suitable."

[0069] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the ratio of oil contained in the residue after heat treatment was 0.3%, and it was evaluated as "suitable."

[0070] (Quality evaluation of carbide residue after heat treatment) The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 64.6, 0.8, and 4.1 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.148 and 0.048, respectively.

[0071] For this reason, the heat treatment residue obtained in this example was classified as anthracite in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0072] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 3

[0073] (Substances subject to thermal decomposition) The pyrolysis target used in this example was acrylonitrile butadiene rubber. The pyrolysis target was placed in a dryer set at 80° C. for 12 hours before heat treatment.

[0074] (inert gas) In this example, argon was used as the inert gas.

[0075] (Heat treatment of pyrolysis target) The heat treatment of the pyrolysis object in this example was carried out in the same manner as in Example 1, except that the amount of pyrolysis object placed in the heat treatment furnace 1 was 43 kg and the gauge pressure of the inert gas was 0.04 MPa in the heat treatment furnace 1. In this example, the ratio of the bulk volume of the pyrolysis object to the volume of the heat treatment furnace was 0.69 according to Mathematical Formula 1.

[0076] (Heat treatment of residue) After the heat treatment step of the object to be thermally decomposed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 600° C. and the heat treatment time was 40 minutes.

[0077] (Odor evaluation of residue after treatment) The odor of the residue was evaluated using the 5-point scale shown in Table 1, and was given a score of 5, so the odor index was evaluated as "suitable."

[0078] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue was measured in the same manner as in Example 1. As a result, the ratio of oil contained in the residue was 0.4%, and it was evaluated as "suitable."

[0079] The residue after heat treatment obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 66.5, 1.8, and 5.3 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.332 and 0.060, respectively.

[0080] For this reason, the heat treatment residue obtained in this example was classified as anthracite in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0081] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 4

[0082] (Substances subject to thermal decomposition) The pyrolysis target used in this example was acrylonitrile butadiene rubber. The pyrolysis target was placed in a dryer set at 80° C. for 12 hours before heat treatment.

[0083] (inert gas) In this example, nitrogen was used as the inert gas.

[0084] (Heat treatment of pyrolysis target) The heat treatment of the object of pyrolysis in this example was carried out in the same manner as in Example 1, except that the gauge pressure of the inert gas in the heat treatment furnace 1 was set to 0.01 MPa.

[0085] (Heat treatment of residue) After the heat treatment step of the object to be pyrolyzed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 900° C. and the heat treatment time was 60 minutes.

[0086] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1, and was given a score of 5, so the odor index was evaluated as "suitable."

[0087] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.3%, and it was evaluated as "suitable."

[0088] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 64.8, 0.3, and 2.9 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.048 and 0.034, respectively.

[0089] For this reason, the heat treatment residue obtained in this example was classified as anthracite in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0090] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 5

[0091] (Substances subject to thermal decomposition) The pyrolysis target used in this example was acrylonitrile butadiene rubber. The pyrolysis target was placed in a dryer set at 80° C. for 12 hours before heat treatment.

[0092] (inert gas) In this embodiment, helium was used as the inert gas.

[0093] (Heat treatment of pyrolysis target) The heat treatment of the pyrolysis object in this example was carried out in the same manner as in Example 1, except that the amount of pyrolysis object placed in the heat treatment furnace 1 was 15 kg and the gauge pressure of the inert gas was 0.08 MPa in the heat treatment furnace 1. In this example, the ratio of the bulk volume of the pyrolysis object to the volume of the heat treatment furnace was 0.24 according to Mathematical Formula 1.

[0094] (Heat treatment of residue) After the heat treatment process for the pyrolysis object, the heat treatment process for the residue was carried out by closing valves 5, 7, and pressure regulator 8 shown in Figure 4, opening valve 9, and reducing the pressure inside heat treatment furnace 1 with vacuum pump 10, and then setting the temperature inside heat treatment furnace 1 to 1000°C and the heat treatment time to 30 minutes.

[0095] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1, and was given a score of 5, so the odor index was evaluated as "suitable."

[0096] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.2%, and it was evaluated as "suitable."

[0097] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 63.2, 0.2, and 2.0 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.038 and 0.024, respectively.

[0098] For this reason, the heat treatment residue obtained in this example was classified as anthracite in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0099] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 6

[0100] (Substances subject to thermal decomposition) The pyrolysis target used in this example was acrylonitrile butadiene rubber. The pyrolysis target was placed in a dryer set at 80° C. for 12 hours before heat treatment.

[0101] (inert gas) In this example, argon was used as the inert gas.

[0102] (Heat treatment of pyrolysis target) The heat treatment of the pyrolysis object in this example was carried out in the same manner as in Example 1, except that the amount of pyrolysis object placed in the heat treatment furnace 1 was 20 kg and the gauge pressure of the inert gas was 0.04 MPa in the heat treatment furnace 1. In this example, the ratio of the bulk volume of the pyrolysis object to the volume of the heat treatment furnace was 0.32 according to Mathematical Formula 1.

[0103] (Heat treatment of residue) After the heat treatment step of the object to be thermally decomposed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 500° C. and the heat treatment time was 30 minutes.

[0104] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1, and was given a score of 4, so the odor index was evaluated as "suitable."

[0105] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.3%, and it was evaluated as "suitable."

[0106] The residue after heat treatment obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 64.8, 0.3, and 2.9 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.383 and 0.048, respectively.

[0107] For this reason, the heat treatment residue obtained in this example was classified as anthracite in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0108] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 7

[0109] (Substances subject to thermal decomposition) The pyrolysis target used in this example was natural rubber (isoprene rubber). The pyrolysis target was placed in a dryer set at 80°C for 12 hours before heat treatment.

[0110] (inert gas) In this embodiment, krypton was used as the inert gas.

[0111] (Heat treatment of pyrolysis target) The heat treatment of the object of pyrolysis in this example was carried out in the same manner as in Example 1.

[0112] (Heat treatment of residue) After the heat treatment step of the object to be thermally decomposed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 800° C. and the heat treatment time was 15 minutes.

[0113] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1, and was given a score of 5, so the odor index was evaluated as "suitable."

[0114] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.2%, and it was evaluated as "suitable."

[0115] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 17.8, 0.4, and 2.1 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.249 and 0.088, respectively.

[0116] For this reason, the heat treatment residue obtained in this example was classified as bituminous coal in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0117] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 8

[0118] (Substances subject to thermal decomposition) The object to be thermally decomposed used in this example was polycarbonate. The object to be thermally decomposed was placed in a dryer set at 80° C. for 12 hours before the heat treatment.

[0119] (inert gas) In this example, carbon dioxide was used as the inert gas.

[0120] (Heat treatment of pyrolysis target) The heat treatment of the object of pyrolysis in this example was carried out in the same manner as in Example 1, except that the gauge pressure of the inert gas in the heat treatment furnace 1 was set to 0.09 MPa.

[0121] (Heat treatment of residue) After the heat treatment step of the object to be pyrolyzed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 600° C. and the heat treatment time was 60 minutes.

[0122] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1, and was given a score of 5, so the odor index was evaluated as "suitable."

[0123] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.2%, and it was evaluated as "suitable."

[0124] The residue after heat treatment obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 69.4, 5.2, and 6.4 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.899 and 0.069, respectively.

[0125] For this reason, the heat treatment residue obtained in this example was classified as bituminous coal in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0126] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 9

[0127] (Substances subject to thermal decomposition) The pyrolysis target used in this example was waste wood from a construction site. The pyrolysis target was placed in a dryer set at 80°C for 12 hours before heat treatment.

[0128] (inert gas) In this example, nitrogen was used as the inert gas.

[0129] (Heat treatment of pyrolysis target) In this example, 20 kg of the material to be pyrolyzed was placed in the heat treatment furnace 1 as shown in FIG. 3 . Then, valves 5 and 7 and pressure regulator 8 were closed, and valve 9 was opened to evacuate the heat treatment furnace 1 using vacuum pump 10. Valve 9 was then closed, pressure regulator 8 was opened, and inert gas was introduced into the heat treatment furnace 1. When the gauge pressure reached 0.1 MPa, valve 5 was opened. At this time, the gauge pressure in the heat treatment furnace 1 was maintained at 0.1 MPa by adjusting the opening of valve 5, and the temperature was raised to 500°C and held for 60 minutes. This separated the oily product and the gas produced by the pyrolysis. In this example, the ratio of the bulk volume of the material to be pyrolyzed to the volume of the heat treatment furnace was 0.32, according to equation 1.

[0130] (Heat treatment of residue) After the heat treatment process of the pyrolysis object, the heat treatment process of the residue was carried out by closing valves 5, 7, and pressure regulator 8 shown in Figure 4, opening valve 9, and reducing the pressure inside heat treatment furnace 1 with vacuum pump 10, and then heat treating the residue under the conditions of a temperature inside heat treatment furnace 1 of 800°C and a heat treatment time of 40 minutes.

[0131] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1, and was given a score of 5, so the odor index was evaluated as "suitable."

[0132] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.4%, and it was evaluated as "suitable."

[0133] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 62.1, 4.0, and 3.7 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.773 and 0.045, respectively.

[0134] For this reason, the heat treatment residue obtained in this example was classified as bituminous coal in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0135] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 10

[0136] (Substances subject to thermal decomposition) The pyrolysis target used in this example was polystyrene. The pyrolysis target was placed in a dryer set at 80° C. for 12 hours before heat treatment.

[0137] (inert gas) In this example, argon was used as the inert gas.

[0138] (Heat treatment of pyrolysis target) The heat treatment of the pyrolysis object in this example was carried out in the same manner as in Example 1, except that the amount of pyrolysis object placed in the heat treatment furnace 1 was 30 kg and the gauge pressure of the inert gas was 0.07 MPa in the heat treatment furnace 1. In this example, the ratio of the bulk volume of the pyrolysis object to the volume of the heat treatment furnace was 0.48 according to Mathematical Formula 1.

[0139] (Heat treatment of residue) After the heat treatment step of the object to be pyrolyzed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 500° C. and the heat treatment time was 60 minutes.

[0140] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1, and was given a score of 4, so the odor index was evaluated as "suitable."

[0141] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.2%, and it was evaluated as "suitable."

[0142] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 71.4, 2.6, and 2.3 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.437 and 0.024, respectively.

[0143] For this reason, the heat treatment residue obtained in this example was classified as bituminous coal in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0144] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Example 11

[0145] (Substances subject to thermal decomposition) The pyrolysis target used in this example was wood chips. The pyrolysis target was placed in a dryer set at 80° C. for 12 hours before heat treatment.

[0146] (inert gas) In this example, carbon dioxide was used as the inert gas.

[0147] (Heat treatment of pyrolysis target) The heat treatment of the thermal decomposition object in this example was carried out in the same manner as in Example 1, except that the amount of the thermal decomposition object placed in the heat treatment furnace 1 was 20 kg and the set temperature in the heat treatment furnace 1 was 450° C. The ratio of the bulk volume of the thermal decomposition object to the volume of the heat treatment furnace in this example was 0.32 according to equation 1.

[0148] (Heat treatment of residue) After the heat treatment step of the pyrolysis object, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the heat treatment time was set to 60 minutes.

[0149] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated using the 5-point scale shown in Table 1. The odor index was therefore rated as "suitable."

[0150] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 0.3%, and it was evaluated as "suitable."

[0151] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 44.6, 2.4, and 4.9 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.646 and 0.082, respectively.

[0152] For this reason, the heat treatment residue obtained in this example was classified as anthracite in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0153] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment, the oil content, and the quality evaluation as a carbonized product all met the standards, and therefore the overall evaluation of this example was "satisfactory." Comparative Example 1

[0154] (Substances subject to thermal decomposition) The material to be thermally decomposed in this comparative example was acrylonitrile butadiene rubber. The material to be thermally decomposed was placed in a dryer set at 80° C. for 12 hours before the heat treatment.

[0155] (Heat treatment of pyrolysis target) 25 kg of the material to be pyrolyzed in this comparative example was placed in the heat treatment furnace 1 shown in FIG. 3, and then the temperature inside the heat treatment furnace 1 was raised to 500° C. and maintained at that temperature for 60 minutes.

[0156] (Heat treatment of residue) After the heat treatment step of the pyrolysis object, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the heat treatment time was set to 60 minutes.

[0157] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated on a 5-point scale shown in Table 1, and was given a rating of 4, so the odor index was evaluated as "suitable."

[0158] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 1.1%.

[0159] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 40.4, 2.0, and 14.6 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.594 and 0.271, respectively.

[0160] For this reason, the heat treatment residue obtained in this comparative example was classified as lignite in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "unsuitable."

[0161] (comprehensive evaluation) From the above results, the quality evaluation of the carbonized product did not meet the standards, and therefore the overall evaluation of this comparative example was unsuitable. This was thought to be because the carbonization treatment was performed without introducing an inert gas, and air flowed into the heat treatment furnace 1 during the carbonization treatment, causing the residue to oxidize. Comparative Example 2

[0162] (Substances subject to thermal decomposition) The material to be pyrolyzed in this comparative example was wood, which was placed in a dryer set at 80°C for 12 hours before heat treatment.

[0163] (inert gas) In this comparative example, argon was used as the inert gas.

[0164] (Heat treatment of pyrolysis target) The heat treatment of the object of thermal decomposition in this comparative example was carried out in the same manner as in Example 1, except that the temperature set in the heat treatment furnace 1 was 450°C.

[0165] (Heat treatment of residue) After the heat treatment step of the object to be pyrolyzed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was set to 300° C. and the heat treatment time was set to 60 minutes.

[0166] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated based on the 5-point scale shown in Table 1, and was given a score of 1, so the odor index was evaluated as "unsuitable."

[0167] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after the heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue was 5.6%.

[0168] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 55.4, 4.1, and 10.9 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.888 and 0.148, respectively.

[0169] For this reason, the heat treatment residue obtained in this comparative example was classified as sub-bituminous coal in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "unsuitable."

[0170] (comprehensive evaluation) From the above results, the odor evaluation of the residue and the quality evaluation of the carbonized product did not meet the standards, so the overall evaluation of this comparative example was inadequate. This is thought to be because the carbonization temperature of the residue was low, so oils such as heavy oil contained in the residue remained without volatilizing, and also because the hydrogen and oxygen contents of the residue were not sufficiently removed. Comparative Example 3

[0171] (Substances subject to thermal decomposition) The material to be pyrolyzed in this comparative example was polystyrene, which was placed in a dryer set at 80°C for 12 hours before the heat treatment.

[0172] (inert gas) In this comparative example, nitrogen was used as the inert gas.

[0173] (Heat treatment of pyrolysis target) The heat treatment of the object of pyrolysis in this comparative example was carried out in the same manner as in Example 1.

[0174] (Heat treatment of residue) After the heat treatment step of the object to be pyrolyzed, the heat treatment step of the residue was carried out in the same manner as in Example 1, except that the temperature inside the heat treatment furnace 1 was 900° C. and the heat treatment time was 1 minute.

[0175] (Odor evaluation of residue after treatment) The odor of the residue after heat treatment was evaluated based on the 5-point scale shown in Table 1, and was given a score of 1, so the odor index was evaluated as "unsuitable."

[0176] (Amount of oil contained in residue after heat treatment) The amount of oil contained in the residue after heat treatment was measured in the same manner as in Example 1. As a result, the proportion of oil contained in the residue after heat treatment was 3.5%.

[0177] The post-heat treatment residue obtained in this example was subjected to organic elemental analysis in the same manner as in Example 1. The weight percentages of C, H, and O were found to be 60.2, 3.2, and 2.7 wt.%, respectively. Based on this, the H / C ratio and O / C ratio were calculated to be 0.638 and 0.034, respectively.

[0178] For this reason, the heat treatment residue obtained in this comparative example was classified as bituminous coal in the coal band, and the quality evaluation of the heat treatment residue as a charcoal was judged to be "suitable."

[0179] (comprehensive evaluation) From the above results, the odor evaluation of the residue after heat treatment did not meet the standard, and therefore the overall evaluation of this comparative example was unsatisfactory. This was thought to be because the heat treatment time of the residue was short, so oils such as heavy oil contained in the residue remained without volatilizing.

[0180] Table 2 shows the heat treatment conditions for the pyrolysis objects and residues in Examples 1 to 11 and Comparative Examples 1 to 3, and Table 3 shows the odor evaluation, oil content, component analysis results, and overall evaluation of the residues after heat treatment.

[0181] [Table 2]

[0182] [Table 3]

[0183] (Industrial Applicability) The results shown in Table 3 indicate that by heat treating the residue of the pyrolysis target under appropriate conditions, it is possible to produce a carbonized product with little odor and a high degree of carbonization. This suggests that the product can be used as a solid fuel such as briquettes, as well as a carbon material. Furthermore, the present invention is extremely simple and can contribute significantly to recycling in a circular economy, making it a highly sustainable method. [Explanation of symbols]

[0184] 1. Heat treatment furnace 2 lid 3. Materials to be pyrolyzed 4 Outlet 5 valves 6 Outlet 7 Valves 8 Pressure Regulator 9 Valves 10. Vacuum pump 11 Piping 12 Inert gas cylinder 13 Residue 14 Heater 15 gauge pressure gauge 16 Mass flow controller 17 Wiring 18 Temperature Controller 19a~19c Thermocouple 20 Wiring 21 Piping 22 Oil storage tank 23 Heater 24 Piping 25 Oil storage tank 26 Wiring 27 Wiring 28a~28c Thermocouple 29 Piping 30 valves 31 Aquarium 32 Piping 33 Gas-liquid separator 34 Piping 35 valves 36 Compressor 37 Piping

Claims

1. A step of placing an object to be thermally decomposed in a heat treatment furnace and replacing the atmosphere in the heat treatment furnace with an inert gas; Following the substitution step, a step of heating the inside of the heat treatment furnace while introducing an inert gas, thereby pyrolyzing the pyrolysis object at a temperature range of 350° C. to 600° C. for a time period of 30 minutes to 90 minutes; After the step of pyrolyzing, a step of heat-treating the residue of the pyrolysis object at a temperature range of 500° C. to 1100° C. for 15 minutes to 80 minutes while introducing an inert gas; The method for producing a residue carbide having an excellent oxygen to carbon mass ratio O / C and an excellent hydrogen to carbon mass ratio H / C through the heat treatment process.

2. A step of placing an object to be pyrolyzed in a heat treatment furnace and removing air from the heat treatment furnace by evacuation; Following the air removal step, a step of heating the heat treatment furnace while introducing an inert gas, thereby pyrolyzing the pyrolysis object at a temperature range of 350° C. to 600° C. for a time period of 30 minutes to 90 minutes; After the pyrolysis step, a step of heat-treating the residue of the pyrolysis object at a temperature range of 500° C. to 1100° C. for 15 minutes to 80 minutes while introducing an inert gas; A method for producing a residue carbide having an excellent oxygen to carbon mass ratio O / C and an excellent hydrogen to carbon mass ratio H / C through the heat treatment process.

3. A step of placing an object to be thermally decomposed in a heat treatment furnace and replacing the atmosphere in the heat treatment furnace with an inert gas; Following the substitution step, a step of heating the inside of the heat treatment furnace while introducing an inert gas, thereby pyrolyzing the pyrolysis object at a temperature range of 350° C. to 600° C. for a time period of 30 minutes to 90 minutes; After the thermal decomposition step, a step of heat-treating the residue of the thermal decomposition object at a temperature range of 500° C. to 1100° C. for 15 minutes to 80 minutes while evacuating the heat treatment furnace to a vacuum; A method for producing a residue carbide having an excellent oxygen to carbon mass ratio O / C and an excellent hydrogen to carbon mass ratio H / C through the heat treatment process.

4. A step of placing an object to be pyrolyzed in a heat treatment furnace and removing air from the heat treatment furnace by evacuation; Following this step, the heat treatment furnace is heated while an inert gas is introduced to thermally decompose the object to be thermally decomposed in a temperature range of 350° C. to 600° C. for a period of 30 minutes to 90 minutes. After this step, a step of heat-treating the residue of the thermal decomposition object at a temperature range of 500° C. to 1100° C. for 15 minutes to 80 minutes while evacuating the heat treatment furnace; A method for producing a residue carbide having an excellent oxygen to carbon mass ratio O / C and an excellent hydrogen to carbon mass ratio H / C through the heat treatment process.

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