JP2011067800A - Method and apparatus for pyrolyzing waste - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a pyrolysis gas and a pyrolysis residue which can be used as a high-quality fuel. <P>SOLUTION: By heating waste 1 under an atmosphere of a low-concentration oxide at 250-300°C in a drying and concurrently de-hydrogen-chloride device 2, by vaporizing water and by discharging a chlorine content 6 out of plastics containing chlorine without pyrolyzing the waste 1, solid components 3 separated from gas components 4 containing the chlorine content 6 from steam 5 are recovered. At this time, since the solid components 3 hardly include ash components generated at the time of pyrolyzation, salt produced by reaction between isolated chlorine emitted from the plastics containing chlorine and an alkali metal in the ash components is hardly included. Then the solid components 3 are heated at 400-500°C in a cracker 7 for pyrolysis, thereby a pyrolysis gas 8, which is a combustible gas containing no chlorine, having less moisture and exhibiting high calorie, and a pyrolysis residue 9 containing fixed carbon as a main component containing no salt content originated from chlorine of the plastics containing chlorine are generated for recovery. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a waste pyrolysis method and apparatus for pyrolyzing waste such as municipal waste to recover a combustible pyrolysis gas and pyrolysis residue mainly composed of fixed carbon.

  As one of the methods for treating and reusing waste such as municipal waste, thermal decomposition treatment of waste is known.

  This is because the waste is heated to a required temperature under a low oxygen atmosphere (including an oxygen-free atmosphere, the same applies below) and thermally decomposed to thermally decompose the combustible matter in the waste. A pyrolysis gas and a pyrolysis residue mainly composed of fixed carbon (char) are generated so that the pyrolysis gas and the pyrolysis residue can be separated and recovered. The combustible pyrolysis gas and A pyrolysis gasification and melting system for waste, in which the pyrolysis residue is introduced into a melting furnace, burned at a high temperature with a small amount of air (for example, an air ratio of about 1.3), and the molten slag is taken out, Attempts have been made to use a carbonization fuel system for waste, in which the recovered pyrolysis residue is reused as fuel in a coal-fired boiler or the like at various facilities as a carbide to achieve thermal recycling. Further, in the above pyrolysis gasification melting system and waste carbonization fuel system, a high temperature gas (hot air) for using a part of the recovered pyrolysis gas as a heat source for the pyrolysis treatment of the waste It has also been considered to use it as a fuel in a hot air generating furnace that generates heat.

  By the way, when the waste such as municipal waste is thermally decomposed, there is a problem of moisture in the waste and mixing of chlorine-containing plastic mainly composed of vinyl chloride resin.

  In other words, even if moisture is mixed during the thermal decomposition of waste, it is only heated to become water vapor, but in order to thermally decompose waste mixed with moisture, it is necessary for thermal decomposition of the waste. In addition to the amount of heat generated, the latent heat of vaporization of water mixed in the waste is required. At this time, when processing a waste having a large amount of water, the latent heat of vaporization of water may occupy 70 to 80% of the total required heat. Therefore, a large amount of heat is required at the time of thermal decomposition of the waste. The problem arises.

  Furthermore, when the pyrolysis gas generated by the thermal decomposition of the waste contains water vapor derived from the water in the waste, there is also a problem that the apparent calorific value of the pyrolysis gas is reduced.

  On the other hand, when a chlorine-containing plastic mainly composed of vinyl chloride resin is mixed in the waste, chlorine (Cl) is released along with the thermal decomposition of the chlorine-containing plastic, and this released chlorine is harmful. Since hydrogen chloride gas is used, there are problems that the gas properties of the pyrolysis gas obtained by the pyrolysis treatment of the waste are significantly deteriorated and the corrosivity is promoted. For this reason, heat recovery devices such as pipelines used for circulation of the pyrolysis gas and combustion devices and boilers used for combustion are greatly limited. In addition, it is necessary to install an exhaust gas treatment device.

Further, a part of chlorine released during the pyrolysis treatment of the chlorine-containing plastic reacts with alkali metals such as K, Ca, Na and the like contained in the ash component in the pyrolysis residue in a free state, and KCl, It becomes a salt such as CaCl ₂ , NaCl and the like, and these salts are contained in the pyrolysis residue. When the pyrolysis residue containing this salt is taken out as a carbide and burned as fuel, chlorine is again produced at that time. Since there is a possibility that hydrogen chloride gas will be generated due to the release, the use of the pyrolysis residue as a fuel requires a process of previously washing the pyrolysis residue with water and desalting it.

  In view of the above, the present applicant, for example, as shown in FIG. 2, the waste a in the external heat kiln furnace b is dried and pyrolyzed using the high-temperature gas d generated in the hot air generator c as a heat source. In the waste pyrolysis gasification and melting apparatus in which the pyrolysis gas e and the pyrolysis residue f are sent to the downstream melting furnace g for processing, the external heat is introduced upstream of the external heat kiln furnace b. As a configuration in which a ventilation dryer h for drying the waste a before being supplied to the kiln furnace b is installed, the waste a is removed from the aeration dryer h by 50% or more of moisture, and this Conventionally, a method of supplying the waste a after drying to the external heat kiln furnace b has been proposed.

  According to such a method, in the external heat kiln furnace b, the waste a whose moisture content has been reduced to 50% or less in advance by the ventilation dryer h can be treated and dried and pyrolyzed. Therefore, it is possible to reduce the water vapor (moisture) contained in the pyrolysis gas e recovered from the external heat kiln furnace b, and to suppress a decrease in the apparent calorific value of the pyrolysis gas e. The calorific value (high calorie) gas can be taken out (see, for example, Patent Document 1).

  Further, as shown in FIG. 3, the present applicant supplies waste a to the primary pyrolysis furnace i, and the temperature at which the chlorine-containing plastic is pyrolyzed and the aluminum alloy does not melt under low oxygen atmosphere conditions. Range, specifically, pyrolyzed by heating to 350 to 450 ° C., and the primary pyrolysis gas j and primary pyrolysis residue k generated were separated and recovered, and then recovered from the primary pyrolysis furnace i. The secondary pyrolysis residue k is further pyrolyzed by supplying the primary pyrolysis residue k to the secondary pyrolysis furnace 1 and heating it to a higher pyrolysis temperature, for example, 750 ° C. under low oxygen atmosphere conditions. A waste pyrolysis gasification method and apparatus for separating and recovering the cracked gas m and the secondary pyrolysis residue n have also been proposed.

  According to the pyrolysis gasification method and apparatus for waste having such a structure, the primary pyrolysis furnace i heats and decomposes the waste a to 350 to 450 ° C., and the primary pyrolysis gas j generated at this time is decomposed. By separating and recovering from the primary pyrolysis residue k, waste a containing moisture to be treated in the primary pyrolysis j gas is released when dried in the primary pyrolysis furnace i. It is possible to recover water vapor (water) and corrosive components such as hydrogen chloride derived from chlorine contained in the chlorine-containing plastic in the waste a. Therefore, after that, the primary pyrolysis residue k recovered in a state separated from the primary pyrolysis gas j containing the moisture and corrosive components from the primary pyrolysis furnace i is converted into the secondary pyrolysis furnace l. And is further pyrolyzed at a higher pyrolysis temperature, and has a high calorific value (high calorie) from the secondary pyrolysis furnace 1 and does not contain corrosive components such as moisture and hydrogen chloride. The secondary pyrolysis gas m, which is a clean flammable gas, and the secondary pyrolysis residue n mainly composed of fixed carbon can be recovered (for example, see Patent Document 2).

JP 11-141834 A JP 2007-238858 A

  However, the technique shown in the above-mentioned Patent Document 1 reduces the water vapor because the waste a after being dried in advance with a ventilation dryer h to remove moisture is thermally decomposed in an external heat kiln furnace b. It is effective for recovering the pyrolysis gas e having a high calorific value. However, since the above-described ventilation dryer h is not intended to completely dry the waste a, the pyrolysis gas e recovered from the external heat kiln furnace b includes the waste a Some water vapor (moisture) derived from the moisture of the water may remain.

  In the method shown in Patent Document 1, the pyrolysis gas e recovered from the external heat kiln furnace b has corrosive properties such as hydrogen chloride derived from chlorine contained in a chlorine-containing plastic such as vinyl chloride resin. The actual situation is that no particular measures are taken to prevent the contained components from being included.

  The technique shown in the above-mentioned patent document 2 separates the primary pyrolysis gas j containing moisture and corrosive components in the primary pyrolysis furnace i, and then converts the remaining primary pyrolysis residue k into the secondary pyrolysis furnace l. The secondary pyrolysis gas m having a higher calorific value (higher calorie) than the secondary pyrolysis furnace l and the secondary pyrolysis residue n mainly composed of fixed carbon are obtained by pyrolysis at a higher pyrolysis temperature. It is effective to generate and recover. However, since the primary pyrolysis furnace i is also subjected to a pyrolysis treatment under a temperature condition of 350 to 450 ° C., chlorine-containing plastic mainly composed of vinyl chloride resin and other 350 to 450 ° C. Since the pyrolysis reaction of a considerable amount of combustible matter in the waste a that is pyrolyzed under temperature conditions proceeds to generate combustible gas, clean combustible fuel that is recovered from the secondary pyrolysis furnace l The amount of recovered secondary pyrolysis gas m, which is a natural gas, is reduced.

  Further, in the primary pyrolysis furnace i, a part of chlorine generated by the pyrolysis of the chlorine-containing plastic is released, and the chlorine is contained under the temperature condition of 350 to 450 ° C. in the primary pyrolysis furnace i. It reacts with the alkali metal contained in the ash component in the primary pyrolysis residue k generated by the thermal decomposition of plastics and other wastes to form a salt, and this salt is secondary to the primary pyrolysis residue k. Since it is sent to the pyrolysis furnace l, the salt is also contained in the secondary pyrolysis residue n recovered from the secondary pyrolysis furnace l. Therefore, when the secondary pyrolysis residue n is used as a fuel, it is the actual situation that a desalination treatment such as washing with water is necessary.

  Therefore, the present inventor further develops the above-described conventionally proposed method so as to recover more high-grade pyrolysis gas that does not contain high-calorie and corrosive components such as hydrogen chloride. In addition, a device for recovering high-grade pyrolysis residues with the property that the concentration of salt produced mainly from fixed carbon (char) and derived from chlorine contained in chlorine-containing plastics is low , Repeated research. As a result, the dehydrochlorination reaction in a low oxygen atmosphere condition of the vinyl chloride resin, which is the main component of the chlorine-containing plastic, proceeds at a temperature condition of about 250 to 300 ° C. with a peak at about 280 ° C. Under this temperature condition, Polyethylene, which is known as the four largest plastics in terms of production, although the decomposition of hydrocarbon components effective for thermal recycling in vinyl chloride resin is suppressed to 10% or less, and the thermal decomposition temperature varies greatly depending on the type of plastic. Among polypropylene, vinyl chloride resin, and polystyrene, polyethylene, polypropylene, and polystyrene other than vinyl chloride resin all undergo thermal decomposition reactions under temperature conditions of about 400 to 500 ° C., and wood and paper The main pyrolysis reaction of the main component of cellulose peaks at around 350 ° C. Paying attention to the point that it proceeds under a temperature condition of about 300-400 ° C., the waste before the thermal decomposition treatment is once heat-treated under a temperature condition of 250-300 ° C. in a low oxygen atmosphere, Moisture contained in the waste can be evaporated, and dechlorination of the chlorine-containing plastic contained in the waste can be carried out without causing much thermal decomposition of the combustible content in the waste. The hydrogen reaction can proceed efficiently, and therefore, after the heat treatment, the solid component is separated from the gas component and recovered, so that it contains a large amount of combustible matter in the waste and is derived from moisture and chlorine-containing plastic. A solid component from which chlorine has been removed can be obtained, and by pyrolyzing the solid component, a pyrolysis gas, which is a combustible gas from which moisture and chlorine have been removed, and the chlorine None of the present invention found that it is possible to produce a salt with the removal of obtaining thermal decomposition residue of the fixed carbon-based, which is suppressed.

  Therefore, the object of the present invention is to recover a large amount of high-grade pyrolysis gas that is high in calories and does not contain corrosive components such as hydrogen chloride, and is mainly contained in fixed carbon and contained in chlorine-containing plastics. An object of the present invention is to provide a waste pyrolysis treatment method and apparatus capable of recovering a high-grade pyrolysis residue in which the content of salt derived from chlorine is reduced.

  In order to solve the above-mentioned problem, the present invention corresponds to claim 1 and proceeds with a dehydrochlorination reaction of chlorine-containing plastic mainly composed of vinyl chloride resin in a low oxygen atmosphere of 3% or less. In addition, heating is performed under a temperature condition in which the decomposition of the hydrocarbon component of the chlorine-containing plastic is suppressed to 10% or less, and the solid component remaining after the release of the gas component containing water vapor and chlorine with the heating is separated from the gas component. Next, the solid component is thermally decomposed under a temperature condition in which the thermal decomposition reaction of the plastics and cellulose mainly constituting the combustible component proceeds in a low oxygen atmosphere of 3% or less, and heat generated. A method for thermally decomposing waste, in which the cracked gas and the pyrolysis residue are separated, respectively, is collected.

  Corresponding to claim 2, the waste is heated to 250 to 300 ° C. in a low oxygen atmosphere of 3% or less, and the solid component remaining after the release of the gas component containing water vapor and chlorine is accompanied by the heating. The solid component is recovered in a state separated from the gas component, and then the solid component is thermally decomposed under a temperature condition of 400 to 500 ° C. in a low oxygen atmosphere of 3% or less, and the generated pyrolysis gas and pyrolysis residue Is a thermal decomposition treatment method for wastes collected separately.

  Further, in accordance with claim 3, the dehydrochlorination reaction of the chlorine-containing plastic mainly composed of vinyl chloride resin proceeds in a low oxygen atmosphere of 3% or less of the waste, and the hydrocarbon component of the chlorine-containing plastic Drying / dehydrochlorination treatment apparatus for heating under a temperature condition in which decomposition is suppressed to 10% or less, and water vapor and chlorine content released from the drying / dehydrochlorination treatment apparatus with heating under the required temperature condition The solid component recovered in a state separated from the gas component containing hydrogen is generated by thermal decomposition under a temperature condition in which the thermal decomposition reaction of the plastics and cellulose mainly constituting the combustible component proceed in a low oxygen atmosphere of 3% or less. A waste pyrolysis treatment apparatus having a configuration including a pyrolysis apparatus configured to separate and recover pyrolysis gas and pyrolysis residue.

  Furthermore, in accordance with claim 4, a drying and dehydrochlorination apparatus for heating waste to 250 to 300 ° C. in a low oxygen atmosphere of 3% or less, and the drying and dehydrochlorination apparatus The solid component recovered in a state separated from the gas component containing water vapor and chlorine released with heating under the required temperature condition is heated at a temperature condition of 400 to 500 ° C. in a low oxygen atmosphere of 3% or less. A waste pyrolysis apparatus having a configuration including a pyrolysis apparatus configured to separate and recover pyrolysis gas and pyrolysis residue generated by decomposition.

  In each of the above-described configurations, the drying and dehydrochlorination apparatus is configured to heat the waste by directly contacting the waste gas with a heating gas serving as a heat source.

  Further, in each of the above configurations, the thermal decomposition apparatus is of a type in which the solid component is indirectly heated by external heat using a heated gas generated in a hot air generator as a heat source to thermally decompose it at a predetermined temperature condition, and The heating gas that has been supplied to the heat source for the thermal decomposition of the solid components in the thermal decomposition apparatus is configured to be used as a heat source for heating waste in the drying and dehydrochlorination treatment apparatus.

According to the present invention, the following excellent effects are exhibited.
(1) The dehydrochlorination reaction of the chlorine-containing plastic mainly composed of vinyl chloride resin proceeds in a low oxygen atmosphere of 3% or less, and the decomposition of the hydrocarbon component of the chlorine-containing plastic is suppressed to 10% or less. And the solid component remaining after the release of the gas component containing water vapor and chlorine is recovered in a state separated from the gas component, and then the solid component is 3% or less. Wastes that are pyrolyzed under the temperature conditions under which the pyrolysis reaction of cellulose and the main combustible components under low oxygen atmosphere are separated, and the generated pyrolysis gas and pyrolysis residue are recovered separately. And more specifically, after the waste is heated to 250 to 300 ° C. in a low oxygen atmosphere of 3% or less, and the gas component containing water vapor and chlorine is released along with the heating. The remaining solid component is recovered in a state separated from the gas component, and then the solid component is pyrolyzed under a temperature condition of 400 to 500 ° C. in a low oxygen atmosphere of 3% or less to generate the pyrolysis. Since there is a method and apparatus for the thermal decomposition treatment of waste that collects gas and thermal decomposition residue separately, the removal of chlorine-containing plastics mainly composed of vinyl chloride resin in the predetermined low oxygen atmosphere of waste It was contained in the waste by heating to 250 to 300 ° C., which is a temperature condition in which the hydrogen chloride reaction proceeds and decomposition of hydrocarbon components effective for thermal recycling of the chlorine-containing plastic is suppressed to 10% or less. Moisture can be released as water vapor and the chlorine content of the chlorine-containing plastic in the waste can be released as a gas component. Solid component is recovered in a state of separating the components, it can be made moisture and chlorine has been removed. Furthermore, since the thermal decomposition reaction of waste hardly proceeds under the above temperature conditions, almost no ash component is generated. Therefore, the above solid component is included in free chlorine and ash component in the chlorine released from the waste. The salt generated by the reaction with the alkali metal is hardly contained. Therefore, by thermally decomposing the solid component at a temperature condition of 400 to 500 ° C., which is a temperature condition in which a pyrolysis reaction of the plastics and cellulose mainly constituting a combustible component proceeds in the predetermined low oxygen atmosphere, Pyrolysis gas that is high-calorie and high-quality flammable gas that does not contain water vapor and chlorine, and high-grade fixed carbon-based pyrolysis residue that does not contain chlorine-derived salts of chlorine-containing plastics in waste Can be generated.
(2) By the above, the pyrolysis gas and pyrolysis residue recovered separately can be used as high-quality, high-calorie fuel gas and high-quality carbonized fuel, respectively, and thermal recycling of waste In this case, the pyrolysis gas and pyrolysis residue can be used as fuel in a wide range of combustion apparatuses.
(3) The drying and dehydrochlorination treatment apparatus is configured so that the waste is directly brought into contact with a heating gas serving as a heat source and heated, so that the waste and dehydrochlorination treatment apparatus can It is possible to increase the thermal efficiency when heating the waste gas, and to easily put the gas component containing water vapor and chlorine released from the waste on the flow of the heating gas used as a heat source for heating the waste than the solid component Can be separated.
(4) The thermal decomposition apparatus is of a type in which the solid component is indirectly heated by external heat using the heated gas generated in the hot air generator as a heat source, and is thermally decomposed under a predetermined temperature condition. By using the heated gas after being supplied to the heat source for thermal decomposition of the solid component as a heat source for heating waste in the drying and dehydrochlorination treatment device, Since the heat remaining in the heated gas after being supplied to the heat source for pyrolysis can be effectively used as a heat source for heating waste in the drying and dehydrochlorination treatment apparatus, it is possible to increase the thermal efficiency of the entire apparatus. It becomes possible.

It is a schematic diagram showing one embodiment of the waste thermal decomposition method and apparatus of the present invention. It is a figure which shows the outline | summary of an example of the thermal decomposition processing method of the waste which the present applicant has proposed conventionally. It is a figure which shows the outline | summary of the thermal decomposition gasification method and apparatus of the waste which the present applicant has proposed conventionally.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 shows an embodiment of a waste pyrolysis method and apparatus according to the present invention, which is as follows.

  That is, the waste 1 is supplied to the drying and dehydrochlorination treatment apparatus 2, and the vinyl chloride resin is mainly used in a state where a low oxygen atmosphere of 3% or less caused by the leakage to the drying and dehydrochlorination treatment apparatus 2 is maintained. 250 to 300 ° C., for example, 300 ° C., which is a temperature condition in which the dehydrochlorination reaction of the chlorine-containing plastic proceeds and the decomposition of hydrocarbon components effective for thermal recycling of the chlorine-containing plastic is suppressed to 10% or less By heating, the waste 1 is dried and a dehydrochlorination reaction of a chlorine-containing plastic (not shown) mainly composed of vinyl chloride resin contained in the waste 1 is performed.

  Next, the solid component 3 is separated from the drying and dehydrochlorination treatment apparatus 2 by the water vapor (moisture) 5 released along with the drying of the waste 1 and the chlorine content such as hydrogen chloride gas released from the chlorine-containing plastic. 6 is recovered in a state separated from the gas component 4 containing 6.

  Next, the solid component 3 recovered from the drying and dehydrochlorination treatment apparatus 2 is supplied to the thermal decomposition apparatus 7 while maintaining a low oxygen atmosphere of 3% or less caused by leakage to the thermal decomposition apparatus 7. , By heating to 400 to 500 ° C., for example, 450 ° C., which is a temperature condition in which the pyrolysis reaction of the plastics and cellulose mainly constituting the combustible component proceeds, and pyrolyzing the combustible component in the solid component 3, A pyrolysis gas 8 which is a combustible gas and a pyrolysis residue 9 mainly composed of fixed carbon (char) are generated, and then the generated pyrolysis gas 8 and the pyrolysis residue 9 are separated and recovered. To do.

  More specifically, the drying and dehydrochlorination treatment apparatus 2 is disposed horizontally, for example, by tilting the cylindrical kiln main body 10 at a required angle so that the outlet 10b at the other end is lower than the inlet 10a at the other end. Thus, it can be rotated. At the inlet 10a side of the kiln main body 10, a screw conveyor type dust feeder 12 connected to the lower end of the charging hopper 11 is attached, and the waste 1 charged into the charging hopper 11 is supplied to the charging hopper 11 as described above. The dust machine 12 can supply the kiln body 10 with the dust machine 12.

  A separation chamber 13 having a solid component recovery port 14 at the bottom is provided on the outlet side of the kiln main body 10. A heating gas inlet 15 is provided in the separation chamber 13, and a burner 16 for auxiliary combustion is installed. . Furthermore, the gas outlet 17 is provided on the inlet 10a side of the kiln main body 10. Thereby, in a state where the kiln main body 10 is rotated at a low speed, the waste gas 1 in the charging hopper 11 is gradually supplied into the kiln main body 10 by the dust feeder 12, and the heating gas 18a at a required temperature is supplied. By introducing the heated gas inlet 15 into the kiln main body 10 and flowing the kiln main body 10 toward the gas outlet 17 in the kiln main body 10, the kiln main body 10 is maintained in the predetermined low oxygen atmosphere. Thus, the waste 1 that is sequentially transferred from the inlet 10a side to the outlet 10b side in the kiln body 10 as the kiln body 10 rotates can be heated to 300 ° C. by direct heating with the heating gas 18a. .

  In addition, when the heat quantity required for heating the waste 1 in the kiln main body 10 to 300 ° C. cannot be obtained by the heating gas 18a, as shown by a two-dot chain line in FIG. The waste 1 can be heated to 300 ° C. in the kiln main body 10 using the high-temperature combustion gas 19 generated by the combustion of as a supplementary heat source. Therefore, as the waste 1 is heated to 300 ° C., the water contained in the waste 1 can be evaporated, and the vinyl chloride contained in the waste 1 is provided. A dehydrochlorination reaction of a chlorine-containing plastic mainly composed of a resin is advanced so that a chlorine content of 6 can be released as a gas such as hydrogen chloride gas.

  Furthermore, the solid component 3 that reaches the separation chamber 13 after the moisture is removed and the chlorine content 6 is removed by the heat treatment at the predetermined temperature is recovered from the solid component recovery port 14 at the bottom of the separation chamber 13. It can be recovered to the line 20.

  On the other hand, a heating gas 18a after being provided as a heat source for heating the waste 1 to 300 ° C., and a combustion gas 19 of the auxiliary burner 16 after being provided as an auxiliary heat source as necessary, Gas component 4 containing chlorine content 6 such as water vapor 5 generated by evaporation of water contained in the waste 1 and hydrogen chloride gas generated by dehydrochlorination treatment of the chlorine-containing plastic in the waste 1 Can be taken out from the gas outlet 17 and discharged through a gas discharge line 21 to a required exhaust gas treatment facility (not shown).

  The thermal decomposition apparatus 7 is arranged concentrically on the outer side of an inner cylinder 23 in which a supply pipe 24 is integrally connected to the inlet 23a side of one end and a discharge pipe 25 is integrally connected to the outlet 23b side of the other end. The pyrolysis kiln furnace 22 having a double cylinder structure in which a heating flow path 27 is formed between the outer cylinder 26 and the outlet 23b side at the other end is lower than the inlet 23a side at one end of the inner cylinder 23. Inclined at a required angle to be placed horizontally and rotated.

  The inlet 23 a of the inner cylinder 23 in the pyrolysis kiln furnace 22 is downstream of the solid component recovery line 20 that leads the solid component 3 from the solid component recovery port 14 of the separation chamber 13 in the drying and dehydrochlorination apparatus 2. A supply device 29 such as a screw conveyor type provided at the lower end of the hopper 28 connected to the hopper 28 is attached so that the solid component 3 in the charging hopper 28 can be supplied into the inner cylinder 23 by the supply device 29. It is.

  On the other hand, at the outlet 23b of the inner cylinder 23 in the pyrolysis kiln furnace 22, the pyrolysis gas 8 and pyrolysis residue 9 generated by the pyrolysis treatment of the solid component 3 are separated, and the pyrolysis gas recovery port at the top is separated. A separation chamber 30 is provided so that it can be recovered from 31 and a pyrolysis residue recovery port 32 at the bottom.

  Further, a hot air generating furnace 34 is connected to a heating gas inlet 33 provided near the outlet 23 b of the inner cylinder 23 in the heating flow path 27 formed between the inner cylinder 23 and the outer cylinder 26 via a heating gas supply line 35. Connected.

  A heating gas outlet 36 is provided near the inlet 23 a of the inner cylinder 23 in the heating channel 27. Thereby, in the state where the pyrolysis kiln furnace 22 is rotated at a low speed, the solid component 3 in the hopper 28 is gradually supplied into the inner cylinder 23 by the supply device 29, while the inner cylinder 23 and the outer cylinder 26 are High-temperature heated gas (hot air) 18 generated by combustion of the required fuel in the hot-air generating furnace 34 is introduced from the heated gas inlet 33 through the heated gas supply line 35 into the heating channel 27 formed therebetween. At the same time, by circulating the inside of the heating channel 27 toward the heating gas outlet 36, the pyrolysis kiln furnace 22 is rotated while the inner cylinder 23 is maintained in the predetermined low oxygen atmosphere. The solid component 3 sequentially transferred from the inlet 23a side to the outlet 23b side in the inner cylinder 23 is indirectly heated to 450 ° C. by external heat using the heated gas 18 as a heat source through the peripheral wall of the inner cylinder 23, and is combustible. Pyrolysis, a natural gas Scan 8 and are to be able to be thermally decomposed in the thermal decomposition residue 9 of the fixed carbon-based.

  Further, after the pyrolysis gas 8 and pyrolysis residue 9 generated by pyrolysis of the solid component 3 are separated in the separation chamber 30, the pyrolysis gas 8 is separated from the pyrolysis gas recovery port 31 at the top of the separation chamber 30. Further, it can be recovered through the pyrolysis gas recovery line 37. On the other hand, the thermal decomposition residue 9 can be recovered through a thermal decomposition residue recovery line 38 from the thermal decomposition residue recovery port 32 at the bottom of the separation chamber 30.

  In the pyrolysis gas recovery line 37, two pyrolysis gas lines 39 and 40 are branched from a required position in the middle, and one pyrolysis gas line 39 is connected to the hot air generating furnace 34, A part of the pyrolysis gas 8 which is the combustible gas can be used as a fuel for supplying the hot air generating furnace 34 to generate the heating gas 18.

  The other pyrolysis gas line 40 branched from the pyrolysis gas recovery line 37 is connected to a burner 16 for auxiliary combustion provided in the drying and dehydrochlorination treatment apparatus 2 so that the pyrolysis gas 8 flows. A part is supplied to the burner 16 for auxiliary combustion so that it can be used as a fuel for combustion.

  A heating gas circulation line 41 provided with a circulation fan 42 is connected to the heating gas outlet 36 of the heating flow path 27 in the thermal decomposition apparatus 7, and flows through the heating flow path 27 in the thermal decomposition apparatus 7 and the above. The heated gas 18 a discharged from the heated gas outlet 36 after being supplied to the heat source for the thermal decomposition treatment of the solid component 3 can be circulated to the hot air generating furnace 34.

  Further, the upstream end of the heated gas recovery line 43 is connected to a required location downstream of the circulation fan 42 in the heated gas circulation line 41, and the downstream end of the heated gas recovery line 43 is divided into two. One branch line 43 a is branched and connected to the heated gas inlet 15 of the separation chamber 13 in the drying and dehydrochlorination apparatus 2, and the other branch line 43 b is connected to an intermediate position of the gas discharge line 21. And a temperature controller 44 in which a temperature detector is connected to each of the branch lines 43a and 43b on the solid component recovery line 20 for introducing the solid component 3 from the fixed component recovery port 14 of the drying and dehydrochlorination apparatus 2. The flow rate adjusting valves 45a and 45b controlled by the above are respectively provided. The temperature controller 44 is recovered from the solid component recovery port 14 of the drying and dehydrochlorination apparatus 2 to the solid component recovery line 20 and detected by the temperature detector of the temperature controller 44. Is always maintained at 300 ° C., a control command is given to the flow rate adjusting valves 45a and 45b on the branch lines 43a and 43b of the heated gas recovery line 43. Thereby, after circulating through the heating flow path 27 of the thermal decomposition apparatus 7, a part of the heating gas 18 a led to the heating gas circulation line 41 from the heating gas outlet 36 is recovered to the heating gas recovery line 43, Heat can be supplied to the heating gas inlet 15 of the drying and dehydrochlorination treatment apparatus 2 through the heating gas recovery line 43 and the one branch line 43a. Heat source for heating the waste 1 to 300 ° C. in the drying and dehydrochlorination apparatus 2 using the heat remaining in the heated gas 18a after being used as a heat source for the thermal decomposition of the solid component 3 in the thermal decomposition apparatus 7 It can be used as. At this time, the heated gas 18a introduced through the heated gas recovery line 43 by the temperature controller 44 so that the temperature of the waste 1 heated in the drying and dehydrochlorination treatment apparatus 2 is maintained at 300 ° C. The supply amount to the drying and dehydrochlorination apparatus 2 through one branch line 43a can be appropriately adjusted. The surplus of the heated gas 18a can be discharged to the gas discharge line 21 via the other branch line 43b.

  As described above, the thermal decomposition treatment of the solid component 3 in the thermal decomposition apparatus 7 using the combustion heat of the thermal decomposition gas 8 that is a combustible gas generated by the thermal decomposition treatment of the solid component 3 in the thermal decomposition apparatus 7 as described above, The waste 1 in the drying and dehydrochlorination apparatus 2 can be heated to 300 ° C. together.

  Since the pyrolysis gas 8 is not generated before the pyrolysis treatment of the solid component 3 in the pyrolysis apparatus 7 is started, such as when the operation of the thermal decomposition apparatus for waste according to the present invention is started, the pyrolysis gas 8 is not generated. An external fuel supply line (not shown) is connected to the burner 16 for auxiliary combustion of the drying and dehydrochlorination treatment apparatus 2 and the hot air generating furnace 34 so that the pyrolysis gas 8 can be used as combustion fuel. Until this occurs, using the combustion heat of the external fuel as a heat source, heating the waste 1 in the drying and dehydrochlorination treatment apparatus 2 to 300 ° C. and the solid component 3 in the pyrolysis apparatus 7 at 450 ° C. It is assumed that the thermal decomposition treatment can be performed.

  46 is combustion air supplied to the burner 16 for auxiliary combustion of the drying and dehydrochlorination treatment apparatus 2, and 47 is combustion air supplied to the hot air generating furnace 34. Reference numeral 48 denotes a temperature controller in which a temperature detection unit is connected to a thermal decomposition residue recovery line 38 for introducing the thermal decomposition residue 9 from the thermal decomposition residue recovery port 32 of the thermal decomposition apparatus 7. Heating that is circulated through the heating flow path 27 of the thermal decomposition apparatus 7 via an adjusting means (not shown) so that the temperature of the thermal decomposition residue 9 recovered from the thermal decomposition apparatus 7 through the residue recovery line 38 is maintained at 450 ° C. What is necessary is just to adjust the flow volume of the gas 18 suitably.

  When the waste pyrolysis apparatus of the present invention having the above-described configuration is used, first, the waste 1 is supplied to the drying and dehydrochlorination apparatus 2, and the predetermined low oxygen atmosphere is formed in the kiln body 10. While being held, the heating gas 18a is heated to 300 ° C. using the heating gas 18a as a heat source and, if necessary, the combustion gas 19 of the auxiliary burner 16 to be burned as an auxiliary heat source. Thereby, in the waste 1, the contained water is evaporated and released as the water vapor 5, and the dehydrochlorination reaction of the chlorine-containing plastic mainly composed of the vinyl chloride resin contained in the waste 1 is performed. By proceeding, chlorine content 6 is released as a gas.

  When the gas component 4 containing the water vapor 5 and the chlorine content 6 is released from the waste 1 as described above, the gas component 4 is removed from the waste in the kiln main body 10 of the drying and dehydrochlorination apparatus 2. A gas discharge line from the gas outlet 17 together with the heating gas 18a after being provided as a heat source for heating 1 and the combustion gas 19 of the burner 16 for auxiliary combustion after being provided as an auxiliary heat source if necessary Accordingly, the solid component 3 remaining after the gas component 4 is separated in the kiln body 10 is freed of moisture and chlorine content 6. It will be.

  Moreover, at 300 ° C., which is the heating temperature of the waste 1 in the drying and dehydrochlorination treatment device 2, the pyrolysis reaction of the combustible portion of the waste 1 hardly proceeds, so that almost no ash component is generated. For this reason, the reaction which the free chlorine in the chlorine content 6 discharge | released from the said waste material 1 produces | generates the alkali metal and salt contained in an ash component is suppressed.

  Therefore, the solid component 3 recovered from the solid component recovery port 14 of the drying and dehydrochlorination apparatus 2 is free of moisture and chlorine, and is also a salt derived from chlorine of the chlorine-containing plastic in the waste 1. It will be almost never included.

  Next, when the solid component 3 recovered from the drying and dehydrochlorination treatment apparatus 2 is supplied to the thermal decomposition apparatus 7, the solid component 3 is converted into the predetermined temperature in the thermal decomposition kiln furnace 22 of the thermal decomposition apparatus 7. The heated gas 18 generated in the hot air generation furnace 34 in a state where the low oxygen atmosphere is maintained is heated to 450 ° C. as a heat source. Thereby, in the solid component 3, a combustible component which is a hydrocarbon component effective for thermal recycling in a chlorine-containing plastic such as vinyl chloride resin from which chlorine has been removed in advance in the drying and dehydrochlorination apparatus 2. The pyrolysis reaction of the main combustible components such as polyethylene, polypropylene, and polystyrene, and the main component cellulose such as wood and paper is carried out, and a pyrolysis gas 8 that is a combustible gas; A pyrolysis residue 9 mainly composed of fixed carbon is produced. At this time, as described above, the solid component 3 to be subjected to thermal decomposition has moisture and chlorine removed in advance and contains almost no salt derived from chlorine of the chlorine-containing plastic in the waste 1. Therefore, the generated pyrolysis gas 8 is a high-calorie and high-quality flammable gas that does not contain water vapor and chlorine as moisture, and the pyrolysis residue 9 is the chlorine-containing plastic in the waste 1. High-quality fixed carbon-based materials that do not contain chlorine-derived salts.

  Therefore, the pyrolysis gas 8 which is the high-calorie and high-quality combustible gas passes through the pyrolysis gas recovery line 37 from the pyrolysis device 7, and the high-grade fixed carbon-based pyrolysis residue 9 is Recovered from the thermal decomposition apparatus 7 through a thermal decomposition residue recovery line 38.

  Thus, according to the waste pyrolysis method and apparatus of the present invention, a high-calorie and high-grade pyrolysis gas 8 can be obtained. It can be used as a gas. Moreover, since the high-quality fixed carbon-based pyrolysis residue 9 with reduced salt derived from chlorine in the chlorine-containing plastic can be obtained, the pyrolysis residue 9 can be used as a high-quality carbonized fuel. . Therefore, when the waste 1 is to be thermally recycled, the pyrolysis gas 8 and the pyrolysis residue 9 can be used as fuel in a wide range of combustion apparatuses.

  In addition, this invention is not limited only to the said embodiment, The drying and dehydrochlorination processing apparatus 2 is the heating temperature of the waste material 1 250-300 degreeC, and some oxygen exists. However, since it is a temperature condition in which the combustion of the waste 1 hardly proceeds, the viewpoint of thermal efficiency and the gas component 4 containing the water vapor 5 and the chlorine content 6 released from the waste 1 are used as a heat source for heating the waste 1. From the viewpoint that separation from the solid component 3 can be easily performed by being discharged on the flow of the combustion gas 19 of the heating gas 18a to be used and the combustion gas 19 of the auxiliary combustion burner 16 used as an auxiliary heat source, the heating gas 18a and Although it is preferable that the combustion gas 19 is in direct contact with the waste 1, the waste 1 is heated to 250 to 300 ° C. in a low oxygen atmosphere of 3% or less and the solid component 3 is converted into a gas component. If recovered by more separated, similarly to the heating method of the solid components 3 in the thermal cracking unit 7 may waste 1 as a form of indirect heating by combustion gases 19 of the burner 16 of the heating gas 18a and assistant 燃用. If the waste 1 is heated to 250 to 300 ° C. in the predetermined low oxygen atmosphere and the solid component 3 can be separated and recovered from the gas component 4, any type of drying and dehydrochlorination apparatus other than the one shown in the figure can be used. 2 may be used.

  The thermal decomposition apparatus 7 heats the combustible component in the solid component 3 by heating the solid component 3 recovered from the drying and dehydrochlorination apparatus 2 to 400 to 500 ° C. in a low oxygen atmosphere of 3% or less. As long as it can be decomposed, any type of thermal decomposition apparatus 7 other than the illustrated one, such as a method of directly heating the solid component 3 with a heat source, may be adopted.

  The thermal decomposition gas 8 recovered from the thermal decomposition apparatus 7 may be processed at a higher temperature to decompose the tar component. In addition, by treating the pyrolysis residue 9 recovered from the pyrolysis apparatus 7 at a higher temperature, the volatile matter remaining in the pyrolysis residue 9 is further gasified, so that the pyrolysis which is a flammable gas The yield of the gas 8 may be increased.

  The heat source for heating the waste 1 in the drying and dehydrochlorination treatment device 2 and the heat source for the thermal decomposition treatment of the solid component 3 in the pyrolysis device 7 should be of a type that can be self-supplied by the combustion heat of the pyrolysis gas 8. However, an external heat source may be used.

  In the pyrolysis residue 9, a sorting device is provided on the downstream side of the pyrolysis residue collection line 38 that collects the pyrolysis residue 9 from the pyrolysis device 7. You may make it raise the ratio of fixed carbon.

  Of course, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Waste 2 Drying and dehydrochlorination processing apparatus 3 Solid component 4 Gas component 5 Water vapor 6 Chlorine content 7 Pyrolysis apparatus 8 Pyrolysis gas 9 Pyrolysis residue 18, 18a Heating gas 34 Hot air generating furnace

Claims (6)

  Temperature conditions under which dehydrochlorination of chlorine-containing plastics mainly composed of vinyl chloride resin proceeds and decomposition of hydrocarbon components in chlorine-containing plastics is suppressed to 10% or less in a low oxygen atmosphere of 3% or less And the solid component remaining after the release of the gas component containing water vapor and chlorine is recovered in a state separated from the gas component, and then the solid component is recovered in a low oxygen atmosphere of 3% or less. Thermal decomposition treatment of waste, characterized by thermal decomposition under the temperature conditions under which the thermal decomposition reaction of plastics and cellulose proceeds, and collecting the generated pyrolysis gas and pyrolysis residue separately Method.   Waste is heated to 250 to 300 ° C. in a low oxygen atmosphere of 3% or less, and the solid component remaining after the release of the gas component containing water vapor and chlorine is recovered in a state separated from the gas component. Next, the solid component is pyrolyzed under a temperature condition of 400 to 500 ° C. in a low oxygen atmosphere of 3% or less, and the generated pyrolysis gas and the pyrolysis residue are recovered separately. A method for thermally decomposing waste.   Temperature conditions under which dehydrochlorination of chlorine-containing plastics mainly composed of vinyl chloride resin proceeds and decomposition of hydrocarbon components in chlorine-containing plastics is suppressed to 10% or less in a low oxygen atmosphere of 3% or less Recovered in a state separated from the gas component containing water vapor and chlorine released from the drying and dehydrochlorination treatment device with heating at the required temperature conditions. It is possible to separate and recover the pyrolysis gas and pyrolysis residue generated by pyrolysis under a temperature condition in which the pyrolysis reaction of plastics and cellulose proceeds under a low oxygen atmosphere of 3% or less. A waste pyrolysis apparatus characterized by comprising a thermal decomposition apparatus.   Drying / dehydrochlorination apparatus for heating waste to 250-300 ° C. in a low oxygen atmosphere of 3% or less, and release from the drying / dehydrochlorination apparatus with heating at the required temperature conditions Pyrolysis gas and pyrolysis generated by pyrolyzing a solid component recovered in a state separated from a gas component containing water vapor and chlorine content in a low oxygen atmosphere of 3% or less under a temperature condition of 400 to 500 ° C. A waste pyrolysis apparatus characterized by comprising a pyrolysis apparatus configured to separate and recover residues.   The waste pyrolysis treatment apparatus according to claim 3 or 4, wherein the drying and dehydrochlorination treatment apparatus is of a type in which the waste is heated in direct contact with a heating gas serving as a heat source.   The pyrolysis apparatus is of a type in which a solid component is indirectly heated by external heat using a heated gas generated in a hot air generating furnace as a heat source and thermally decomposed at a predetermined temperature condition, and the solid component in the pyrolysis apparatus is 6. The waste pyrolysis apparatus according to claim 3, 4 or 5, wherein the heating gas after being supplied to the heat source for pyrolysis is used as a heat source for heating waste in the drying and dehydrochlorination apparatus. .

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