JP2010189700A - Method and apparatus for pyrolyzing metal-mixed plastic waste and recovering metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for pyrolyzing metal-mixed plastic waste as it is in a glass-fused liquid and recovering metals precipitated in the glass-fused liquid, metals dissolved in the glass-fused liquid, metals volatilized/dispersed in a pyrolysis gas and metals dissolved in cooling water. <P>SOLUTION: The metal-mixed plastic waste is pyrolyzed in a pyrolysis apparatus 21 at stable temperature so that the calorie to be absorbed when the metal-mixed plastic waste is pyrolyzed is complemented with the calorie to be generated when plastics are burned and the calorie to be generated when the combustion gas is reacted with constituent substances of the glass-fused liquid and the calorie retained in the pyrolysis apparatus is adjusted by the volume of the glass-fused liquid. Metals precipitated in the glass-fused liquid are recovered in a precipitated metal recovery apparatus 10 together with the glass-fused liquid. Metals dissolved in the glass-fused liquid are precipitated on a DC electrode and the precipitated metals are recovered in a water-cooled dissolved metal recovery apparatus 18 together with the glass-fused liquid. Metals volatilized/dispersed in the pyrolysis gas are solidified/recovered by cooling the metal-containing pyrolysis gas with water in cooling tanks 23-27. Active substances contained in the pyrolysis gas are oxidized/burned to obtain stable gas and the stable gas is discharged. Metals dissolved in cooling water are neutralized in a neutralization tank 32 and recovered as precipitates and the water is recovered and reused. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic component comprising an integrated circuit and terminal wiring, or an electric product equipped with these, or a metal mixed plastic waste such as shredder dust mixed with metal and plastic cut from an automobile, in a high-temperature glass as it is. A method and apparatus for recovering metal by thermally decomposing a metal-mixed plastic waste that is thermally decomposed with a melt and recovering the metal are provided.

  Metal separation from metal-mixed plastic waste is pulverized, and specific gravity sorting, wind sorting, magnetic sorting, and electrostatic sorting are tried, but it is difficult to pulverize electronic parts and shredder dust made of hard plastic and metal. Even if powdered, the shape, density, and magnetism are various, and it is not an effective method. On the other hand, many of the plastics used for dry distillation pyrolysis have high heat resistance. If undecomposed parts remain even after high-temperature pyrolysis and contain halogen-based plastics, secondary synthesis of harmful halogen compounds such as PCB and dioxin is performed. Easy to wake up. A part of the integrated circuit is smelted and recovered in a metal smelting furnace, but for industrial purposes, a high metal content is required, and smelter dust having a low metal content is not smelted and recovered.

  On the other hand, the melting temperature of glass used in industry is around 1400 ° C, and if it is pyrolysis in a glass melt with a stable temperature distribution in this temperature range, metal mixed plastic waste hard and plastic with high heat resistance can also be used. By being completely decomposed and pyrolyzed, the metal can be recovered according to its properties by precipitating in the glass melt with its melting point and boiling point, dissolving, or volatilizing into the pyrolysis gas. Further, according to this method, the plastic is completely decomposed and no harmful halogen compound is synthesized.

However, unlike industrial glass manufacturing methods in which raw materials with high purity of silicon oxide are externally heated or melted with an AC electrode, a method by internal heating that performs thermal decomposition while oxidizing and burning plastics in a glass melt with pressurized oxygen 2Na ₂ O → Na ₂ O ₂ + Na ₂ → 2Na ₂ O and 2K ₂ O → K ₂ O ₂ + K ₂ → 2K ₂ O, which are caused by sodium oxide and potassium oxide, which are constituents of the glass melt, at high temperatures. a reversible reaction, and the reaction water and carbon monoxide by burning _{plastics, Na + H 2 O → NaOH} + H, 2Na + CO → Na 2 O + C, NaOH + CO + O → NaCO 3 + H, 2NaCO 3 → Na 2 O + 2CO + 3O, K + H 2 O → KOH + H, 2K + CO _{→ K 2 O + C, KOH} + CO + O → KCO 3 + H, 2KCO 3 K ₂ O + 2CO + 3O reaction to generate the. In addition, calcium oxide, which is a composition material of the glass melt, causes a reaction of CaO + CO → CaC + O ₂ , 2CaC + H ₂ O + O → C ₂ H ₂ + 2CaO + O → 2CaO + H ₂ O + 2C by water and carbon monoxide by oxidative combustion at a high temperature. These reactions occur throughout the glass melt and generate an active substance with foaming.

On the other hand, the pyrolysis gas generated from the glass melt is such that carbon monoxide generated by plastic combustion is 2CO → C + CO _{2 at} around 800 ° C., and CO + H ₂ O → CO ₂ + H _{2 in} the temperature range of 700 ° C. to 400 ° C. Reacts with carbon to release active carbon and hydrogen. In addition, the metal contained in the gas is a substance contained in the metal-mixed plastic waste and becomes a metal salt of oxide, nitride, chloride, sulfide, hydroxide, respectively, and some of the cooling water is cooled by water cooling of the pyrolysis gas. Dissolve in Therefore, when thermal decomposition is performed by internal heating, it is necessary to cope with these generated reactions. Under this circumstance, a processing technique relating to metal mixed plastic waste is disclosed.

  For example, in Patent Document 1, an olefin resin and a styrene resin having a high content are separated and recovered from waste home appliance shredder dust, the olefin resin is converted into a recycled resin, and the styrene resin is pyrolyzed to produce oil and reused as a styrene monomer. It is what.

  In Patent Document 2, exhaust gas or powder waste from a waste carbonization furnace is pressed into a glass melt with air to make it harmless.

Japanese Patent Laid-Open No. 2001-224652 Japanese Patent Laid-Open No. 2003-20360

  The invention disclosed in Patent Document 1 described above is a combination of specific gravity sorting, wind sorting, magnetic sorting, and electrostatic sorting, separating and collecting olefin resin and styrene resin from shredder dust, and kneading the collected resin into a kneader. The metal piece is removed and reused by the attached melt filter. In Patent Document 1, the particle size of the shredder dust is 2 cm. However, with this particle size, the amount of specific resin that can be recovered from the shredder dust in which metal and plastic or different types of plastics are combined is limited, which increases the recovery efficiency. Must be hand-sorted, or made finer by freeze pulverization or polishing and combined with specific gravity sorting, wind sorting, magnetic sorting, and electrostatic sorting.

  In the invention disclosed in Patent Document 2 described above, the waste carbonization furnace exhaust gas is pressed into the glass melt with air, and harmful halogen compounds contained in the exhaust gas are made harmless by high-temperature thermal decomposition. However, there is a possibility that unsaturated hydrocarbons in the exhaust gas may detonate by injecting the exhaust gas with air, and the amount of combustion heat, the generated carbon monoxide and water, and the water in the exhaust gas are the composition of the glass melt. Due to the reaction with the substance, the glass melt may become a high temperature that the heat-resistant material cannot handle. Furthermore, nitrogen oxides are produced at high temperatures with oxygen and nitrogen in the compressed air, and the metal in the exhaust gas becomes nitrate metal and becomes an eluting harmful metal. Similarly, Patent Document 2 attempts to detoxify harmful halogen compounds contained in powder waste by press-fitting the powder waste into the glass melt with air. The amount of waste increases, and waste with low silicon oxide content does not turn into glass even if it is cooled and discharged, but it regenerates hazardous waste from which metal nitrate is eluted.

  The present invention relates to an electronic component comprising an integrated circuit and terminal wiring, or an electric product equipped with these, or a metal mixed plastic waste such as shredder dust mixed with metal and plastic cut from an automobile, in a high-temperature glass as it is. It is injected into the melt, and the metal is separated by pyrolysis and recovered according to its properties. It can respond stably to the reaction generated by the pyrolysis, and the glass melt and solidified product with a high metal content. The problem is to recover the metal from the precipitate.

  The method for recovering metal from the metal mixed plastic waste according to claim 1 of the present invention is a method of thermal decomposition in which the metal mixed plastic waste is pressed into a glass melt at a liquid temperature of about 1400 ° C. in the pyrolysis step. Becomes a gas, and the metal precipitates in the glass melt according to its melting point and boiling point, dissolves, and volatilizes into the gas. The metal precipitated and dissolved in the glass melt is collected together with the glass melt in the step of collecting it, and the metal volatilized in the gas is recovered by cooling the gas with water to solidify the metal in the step of collecting it. The metal dissolved in cooling water by water cooling is recovered by neutralizing the cooling water and precipitating the metal in the water treatment process, and recovering and reusing the neutralized cooling water for thermal decomposition. Thus, the metal to be recovered is stably recovered according to its properties.

  In the step of injecting the metal-mixed plastic waste according to claim 2 into a high-temperature glass melt and thermally decomposing it, the amount of combustion heat of the plastic by the injected oxygen and the amount of reaction heat generated by the composition material of the glass melt by this combustion gas The amount of heat absorbed by pyrolysis is replenished, and the fluctuation of the amount of replenishment heat is adjusted by the amount of heat retained by the amount of glass melt. When the temperature of the glass melt decreases during pyrolysis, waste plastic is inserted instead of metal mixed plastic waste, and the liquid temperature depends on the heat of combustion of the plastic and the reaction heat of the composition of the glass melt that reacts with the combustion gas. When the liquid temperature of the glass melt rises, glass powder is used instead of the metal mixed plastic waste, and the liquid temperature is lowered by the temperature absorption heat quantity of the glass powder. It has the effect of thermal decomposition with glass melt.

  In the step of recovering the metal precipitated or dissolved in the glass melt according to claim 3, the metal precipitated at the bottom of the glass melt is discharged together with the glass melt and recovered by cooling with water, and the metal dissolved in the glass melt is glass. It has the effect of recovering metal with a glass melt with a high metal content by depositing it on the DC electrode deployed in the melt, switching the anode and cathode apart, discharging it with the glass melt and recovering it with water. .

  In the step of cooling the gas generated by pyrolysis according to claim 4 and recovering the metal contained in the gas, oxygen is injected and contained in the pyrolysis gas while recovering the metal that is solidified by cooling the pyrolysis gas with water. The active substance is oxidized and combusted and exhausted with a stable gas. Metal dissolved in cooling water by water cooling is recovered by neutralizing the cooling water and recovering it, and recovering and reusing the water after processing has the effect of recovering the metal as a solidified product or a precipitate with a high metal content. ing.

  The thermal decomposition apparatus of the metal-mixed plastic waste processing apparatus according to claim 5 is configured such that the amount of heat absorbed by the thermal decomposition of the metal-mixed plastic waste is determined by the combustion heat quantity of the plastic and the reaction heat quantity of the combustion gas and the glass melt composition material. An amount of glass melt that can be replenished and the amount of replenishment heat can be adjusted by the amount of retained heat is stored, and a glass melt storage tank is provided with a residence space for pyrolysis gas at the top of the liquid surface. The glass melt storage tank is provided with a partition wall at the lower part of the liquid surface, and the charging side is a plastic oxidative combustion and reaction zone by the composition of combustion gas and glass melt, and the other side is a zone with little reaction. In the reaction zone, the metal precipitated in the glass melt is recovered with water from the precipitated metal recovery device provided on the side wall together with the glass melt, and in the low reaction zone, a dissolved metal recovery unit is provided with a DC electrode on the side wall. The metal melt | dissolved in the glass melt is deposited, and the melt | dissolved metal which peeled by switching the anode and cathode of a DC electrode is water-cooled and recovered with a glass melt.

  The pyrolysis gas is discharged from the pyrolysis gas retention space of the glass melt storage tank to the gas processing apparatus. The gas processing device is provided with a plurality of cooling tanks for each connected temperature range, and the volume of the cooling tank is increased so that the lower the temperature range, the lower the gas pressure, and the metal contained in the gas while water cooling the gas to the set temperature. Solidify and recover. Carbon or hydrogen liberated from the pyrolysis gas carbon monoxide by water cooling and the active substance generated by the reaction between the combustion gas and the glass melt composition material are oxidized and burned with the injected oxygen to have stable properties. The final cooling tank is a water-driven jet pump that draws gas from a plurality of cooling tanks connected to each other and has a pressure at which gas generated from the precipitated metal recovery device and the dissolved metal recovery device can be received. Then, the gas is sucked in, water-cooled to 100 ° C. or lower with driving water, steam is used as water, and the gas is separated and discharged. The water treatment device neutralizes the water separated from the gas and precipitates and recovers the metal dissolved in the water with a metal salt. By recovering and reusing the treated water, it has the function of recovering metals in glass melts, solidified products, and precipitates with high metal content in response to thermal decomposition and water cooling of the pyrolysis gas. ing.

  In the pyrolysis apparatus according to claim 6, in order to avoid oxidative wear due to high temperature in the input side reaction section, oxygen which has been passed through the inner pipe of the outer pipe and the inner pipe is cooled and cooled with water of the outer pipe. The amount of heat absorbed by the thermal decomposition is compensated by the heat of combustion of the plastic and the reaction heat of the glass melt composition reacting with the combustion gas, and the metal mixing is performed by adjusting the amount of replenishment heat by the amount of heat retained by the amount of glass melt. Thermally decompose plastic waste at a stable temperature. When the temperature of the glass melt decreases during pyrolysis, waste plastic is introduced from the inlet, and the glass is heated by the reaction heat of the glass melt composition material that reacts with the amount of combustion heat of the plastic and the combustion gas. When the liquid temperature of the melt rises, glass powder is introduced from the inlet, and the liquid temperature is lowered by the temperature rise absorption heat quantity of the glass powder, so that the thermal decomposition is performed with the glass melt at a stable liquid temperature. have.

  Of the precipitated metal recovery device and the dissolved metal recovery device according to claim 7, the precipitated metal recovery device is provided on the side wall of the reaction section on the input side, according to the amount of the non-gasification substance contained in the metal mixed plastic waste. Depending on the fluctuating surface position of the molten glass, the precipitated metal is discharged together with the molten glass from the discharge port at the bottom of the precipitated metal recovery device, and recovered by cooling with water. In the molten metal recovery apparatus, an electrode section is provided on the side wall of one reaction-reducing section, and the anode and cathode DC electrodes are alternately arranged in the section to deposit metal on the DC electrode while energizing. The compartment is closed according to the energized state of the DC electrode and the glass melt surface position, the anode and the cathode are switched, the metal is peeled off from the electrode, the molten metal is discharged together with the glass melt from the discharge port at the bottom of the compartment, and it is cooled with water and collected. It has the effect | action which collect | recovers glass melts with a high metal content rate.

  Of the gas treatment device and the water treatment device according to claim 8, in the gas treatment device, a cooling bath is provided for each temperature range of 1400 ° C to 800 ° C, 800 ° C to 400 ° C, and 400 ° C to 150 ° C, and each cooling bath is provided. Adjusts the amount of gas and the amount of steam generated by water cooling with the tank volume, lowers the cooling tank in the low temperature range, and cools the gas to the set temperature. In a cooling bath of 800 ° C. to 400 ° C., carbon or hydrogen is liberated from carbon monoxide of the pyrolysis gas, so that oxygen is injected to oxidize and burn to carbon dioxide or steam, and the combustion gas and glass melt composition material The active substance generated by this reaction is oxidized and burned with the injected oxygen to obtain stable properties. The cooling tank below 150 ° C. is the final cooling tank, which sucks the gas from the cooling tank at 400 ° C. to 150 ° C. and receives the gas generated by the precipitated metal recovery device and the dissolved metal recovery device. The water tank and the water tank at the bottom of the water tank are open and the water tank is a double water tank. Stabilize the gas at the set low pressure. The gas is set to 100 ° C. or less by water-cooled suction by a jet pump driven by water, and the separated gas is discharged by using steam as water. Water separated from the gas is introduced into the water treatment equipment, and the metal dissolved in the water is neutralized and recovered by water cooling and recovered. The water after the treatment is recovered and reused, so that pyrolysis and pyrolysis gas can be recovered. Corresponds to the reaction by water cooling, and has the effect of recovering the metal with a solidified product or precipitate having a high metal content.

  In the present invention, metal-mixed plastic waste is injected into a high-temperature glass melt as it is, the metal is separated by pyrolysis, precipitated into a glass melt, dissolved, and vaporized into pyrolysis gas. And a method and apparatus for collecting them accordingly. Thermal decomposition is performed by replenishing the amount of heat absorbed by thermal decomposition with the amount of combustion heat of the plastic and the amount of reaction heat between the combustion gas and the glass melt composition, and adjusting the variation in the amount of heat supply with the amount of heat retained by the amount of glass melt. Amount of glass melt determined by the amount of plastic and metal composition of metal-mixed plastic waste, from collecting a small amount of rare metal by collecting parts to collecting large amounts of electrical products and automobile shredder dust It becomes a method and an apparatus which collect | recovers metals efficiently with the apparatus of the scale according to.

  Embodiments of the present invention will be described with reference to the drawings.

  Hereinafter, a method for thermally decomposing metal-mixed plastic waste according to an embodiment of the present invention and recovering metal will be described with reference to FIG.

  FIG. 1 is a flowchart of a method for recovering metal from a metal-mixed plastic waste according to an embodiment of the present invention. In FIG. 1, step S-1 is a process of thermally decomposing metal mixed plastic waste. Pyrolysis involves injecting metal-mixed plastic waste and oxygen into the glass melt, supplementing the heat of combustion of the plastic and the heat of reaction between the combustion gas and the glass melt composition material, and replenishing the amount of heat absorbed by the pyrolysis. Is adjusted by the amount of heat retained by the amount of glass melt. When the amount of plastic during thermal decomposition is insufficient and the liquid temperature of the glass melt is lowered, waste plastic is added to increase the liquid temperature, and when the amount of plastic is excessive and the liquid temperature is increased, glass powder is added to the liquid. By lowering the temperature, thermal decomposition is performed with a stable glass melt.

  S-2 is a process of metal recovery and gas and water treatment. Due to the thermal decomposition, the plastic of the metal mixed plastic waste becomes a gas, and the metal becomes a volatilized metal that precipitates and dissolves in the glass melt due to its melting point and boiling point, and is scattered in the pyrolysis gas. The metal precipitated in the glass melt is recovered by cooling with the glass melt from the bottom of the glass melt, and the dissolved metal is deposited on the DC electrode, peeled off, recovered by water cooling with the glass melt, and the volatilized metal is recovered by water cooling of the pyrolysis gas. Solidify and collect. The pyrolysis gas is water-cooled step by step in the set temperature range, oxygen is injected in the temperature range of 800 to 400 ° C., and the active substance contained in the pyrolysis gas is oxidized and burned to form a stable property gas. The water and gas are separated by a jet pump driven at 100 ° C. or lower. The separated gas is exhausted, and the water in which the metal is dissolved in the metal salt by water cooling is precipitated by neutralization to recover the metal, and the treated water is recovered and reused.

  In the above description, in the method of thermally decomposing a metal mixed plastic waste according to the present embodiment and recovering the metal, the metal is made according to its property by pyrolyzing the metal mixed plastic waste in a glass melt. Thus, it is a method for efficiently recovering glass melts, solidified products and precipitates with a high metal content.

  An apparatus for thermally decomposing metal-mixed plastic waste according to an embodiment of the present invention and recovering metal will be described below with reference to FIG. FIG. 2 is a configuration diagram of a thermal decomposition apparatus among apparatuses for thermally decomposing metal mixed plastic waste according to an embodiment of the present invention and recovering metal. In FIG. 2, the thermal decomposition apparatus among the apparatuses for thermally decomposing metal mixed plastic waste and recovering metal includes a slide gate 1, a press-fitting device 2, an input port 3, a feeding device 4, a press-fitting cylinder 5, and an oxygen water-cooled supply unit 2. Heavy pipe 6, reaction section 7, partition 8, section 9 with little reaction, precipitated metal recovery device 10, dissolved metal recovery device 11, precipitated metal recovery port 12, DC electrode 13, slide gate 14, partition 15, electrode section 16, It consists of a molten metal recovery port 17, a molten metal water-cooled recovery device 18, a sealed compartment 19, and a water-sealed partition wall 20.

  Metal mixed plastic waste is inserted from the inlet 3 with the slide gate 1 shutting off the pyrolysis gas closed and the press-fitting device 2 raised, and sent to the slide gate 1 by the feeding device 4, and the slide gate 1 is opened. The feed device 4 is sent to the press-fitting cylinder 5 while preventing leakage of pyrolysis gas, the feed device 4 is pulled, the slide gate 1 is closed, the pyrolysis gas is shut off, the press-fitting device 2 is lowered and press-fitted into the glass melt. The pressed metal mixed plastic waste is oxidized and burned with oxygen pressed in the double pipe 6 for oxygen water cooling supply, and sent to the reaction section 7 with the pressure of the gas generated while reacting the glass melt composition with the combustion gas. In the reaction section 7, the upper layer portion of the glass melt is allowed to flow from the partition wall 8 to the section 9 with less reaction while continuing the combustion and the reaction of the glass melt composition material. A plurality of oxygen water cooling supply double pipes 6 are provided for maintenance and repair.

  The precipitated metal recovery device 10 is provided on both side walls of the reaction zone 7, and the dissolved metal recovery device 11 is provided on both side walls of the zone 9 with less reaction. In the precipitated metal recovery device 10, when the liquid level of the glass melt rises from the set liquid level position and it is not necessary to discharge the glass melt containing the dissolved metal from the molten metal recovery device 11, the precipitated metal recovery port 12 is used. The glass solution containing the precipitated metal is discharged from the water and recovered by cooling with water. The DC electrode 13 of the molten metal recovery apparatus 11 is provided with an electrode section 16 partitioned by a partition wall 15 provided with a slide gate 14 on the side wall portion of the section 9 with little reaction. Usually, the slide gate 14 is opened and the DC electrode is energized to react. The metal dissolved in the glass melt in the compartment 9 with a small amount is deposited on the DC electrode 13. When it is necessary to recover the molten metal depending on the state of energization of the DC electrode 13, the slide gate 14 is closed, and the deposited metal separated from the electrode by switching the anode and the cathode of the DC electrode 13 together with the glass melt is dissolved from the molten metal recovery port 17. It is discharged to a water cooling recovery device 18 and recovered by cooling with water. Since the molten metal recovery device 11 leaks pyrolysis gas when the slide gate is opened / closed or when the electrode is replaced, a sealed compartment 19 is provided to prevent the gas from leaking. Pump and ventilate. The precipitated metal recovery device 10 and the molten metal water-cooled recovery device 18 are provided with a water-sealed partition wall 20 and are pumped to the gas processing device when the generated water vapor pressure accompanying the cooling of the metal-containing glass solution exceeds a predetermined pressure. When starting the pyrolysis tank, a carbon electrode is placed on the glass powder laid in the reaction section 7, energized, the glass powder is melted by resistance heat, and oxygen can be injected. Oxygen is injected, the glass melt is filled up to a predetermined liquid level, and the system is started.

  An apparatus for recovering metal from metal mixed plastic waste according to an embodiment of the present invention will be described below with reference to FIG. FIG. 3 is a configuration diagram of a gas treatment device and a water treatment device among the devices for recovering metal from the metal mixed plastic waste according to the embodiment of the present invention. In FIG. 3, the gas treatment device and the water treatment device among the devices for recovering the metal from the metal mixed plastic waste are the pyrolysis device 21, the pyrolysis gas retention space 22, the cooling bath 23, the cooling bath 24, and oxygen water cooling supply. The double pipe 25, the oxygen supply device 26, the cooling tank 27, the cooling tank 28, the inner water tank 29, the outer water tank 30, the jet pump 31, the exhaust tank 32, the neutralization tank 33, the water collection tank 34, and the water cooling tank 35 are configured. .

  The gas is discharged into the cooling tank 23 having a space volume in which the gas pressure is lower than the pyrolysis gas retention space 22 of the pyrolysis tank 21. In the cooling bath 23, the water is cooled to about 800 ° C., and the metal solidified in the temperature range of 1400 to 800 ° C. is collected in a dust collection bath at the lower portion of the cooling bath. The water cooled in the cooling tank 23 is discharged to the cooling tank 24 having a space volume in which the gas pressure is lower than that of the cooling tank 23. In the cooling tank 24, the water from the double pipe 25 for supplying oxygen water is supplied to cool to around 400 ° C., and the metal solidified in the temperature range of 800 to 400 ° C. is collected in a dust collecting tank at the lower part of the cooling tank. Oxygen that has been water-cooled by a double pipe 25 for supplying oxygen water is supplied from a supply device 26, and the active substance contained in the pyrolysis gas is oxidized and burned to form a stable gas. The water-cooled gas in the cooling tank 24 is discharged to a cooling tank 27 having a space volume in which the gas pressure is lower than that of the cooling tank 24. In the cooling tank 27, the water is cooled to around 150 ° C., and the metal that solidifies in the temperature range of 400 to 150 ° C. is collected in a dust collection tank below the cooling tank. The water cooled in the cooling tank 27 is discharged to the cooling tank 28 having a space volume in which the gas pressure is lower than that of the cooling tank 27.

  Since the cooling tank 28 stably sucks the gas of the cooling tank 27 as the final cooling tank and receives the gas generated by the sealed compartment 19, the precipitated metal recovery device 10, and the molten metal water-cooled recovery device 18, A double water tank of a water-sealed inner water tank 29 and an outer water tank 30 that opens at the bottom is opened, and the gas in the inner water tank 29 is sucked by a water-driven jet pump 31 and linked to the water level of the inner water tank 29. The gas in the inner water tank is stabilized at a low pressure at the overflow water level of the outer water tank 30. The gas sucked by the jet pump 31 driven by water is 100 ° C. or less by driving water, the water vapor is returned to the water in the exhaust tank 32 of the double water tank having the same function as the cooling tank 28, and the separated gas has a stable pressure. Exhaust with. The overflow water in the exhaust tank 32 is received by the outer water tank 30 and sent to the neutralization tank 33 as overflow water from the outer water tank 30, and the metal dissolved in the water is neutralized by water cooling and recovered as a precipitate. The treated water is collected and stored in the water collection tank 34, the driving water for the jet pump 31 is set at a predetermined temperature in the water cooling tank 35, and the other water is supplied to the places where water is required. A plurality of apparatuses from the cooling tank 23 to the water cooling tank 35 are provided for maintenance and repair.

  In the above description, in the apparatus for recovering metal from the metal-mixed plastic waste according to the present embodiment, a plurality of metal-mixed plastic charging devices and pyrolysis gas treatment devices are provided, so that a glass melt that cannot be temporarily stopped is provided. Can be used as a device that operates continuously until the heat-resistant material wears out.

It is a flowchart of the method of thermally decomposing the metal mixed plastic waste concerning embodiment of this invention, and collect | recovering metals. It is a block diagram of the thermal decomposition apparatus among the apparatuses which thermally decompose the metal mixed plastic waste concerning embodiment of this invention, and collect | recover metals. FIG. 2 is a configuration diagram of a gas treatment device and a water treatment device among devices for thermally decomposing metal mixed plastic waste according to an embodiment of the present invention and collecting metal.

1: Slide gate 2: Press-in device 3: Input port 4: Feeder 5: Press-in tube 6: Double tube for oxygen water cooling supply
7: Reaction compartment
8: Bulkhead
9: Section with little reaction
10: Precipitated metal recovery device
11: Molten metal recovery device
12: Precipitated metal recovery port
13: DC electrode
14: Slide gate
15: Bulkhead
16: Electrode compartment
17: Molten metal recovery port
18: Molten metal water cooling recovery device
19: Sealed compartment
20: Water-sealed partition wall
21: Pyrolysis device
22: Thermal decomposition gas retention space
23: Cooling tank
24: Cooling tank
25: Double pipe for oxygen water cooling supply
26: Oxygen supply device
27: Cooling tank
28: Cooling tank
29: Inner water tank
30: Outside water tank
31: Jet pump
32: exhaust tank
33: Neutralization tank
34: Catchment tank
35: Water cooling tank

Claims (8)

  Pressing metal mixed plastic waste into a high-temperature glass melt and pyrolyzing, recovering the metal precipitated or dissolved in the glass melt, cooling the gas generated by the pyrolysis with water, and removing the metal contained in the gas Metal from metal-mixed plastic waste is recovered by solidifying and recovering, and water treatment by recovering and recovering the cooling water after metal recovery by precipitating and recovering metal dissolved in cooling water by water cooling. A method of recovering metal by thermally decomposing metal-mixed plastic waste characterized by recovering and recycling used water.   In the step of thermally decomposing the metal mixed plastic waste with a high-temperature glass melt, the amount of heat absorbed by the thermal decomposition of the heat absorbed by the oxygen in which the plastic in the metal mixed plastic waste is oxidized and the glass melt The composition material is replenished with the amount of heat generated by reacting with the combustion gas, and the fluctuation of the replenishment heat amount is adjusted with the amount of heat retained by the amount of the glass melt to perform thermal decomposition. When the liquid temperature of the glass melt decreases during pyrolysis, waste plastic is added, and the liquid temperature is increased by the heat of reaction of the composition of the glass melt that reacts with the combustion heat of the plastic and the combustion gas. The glass powder is added when the liquid temperature rises, and the liquid temperature is lowered by the temperature rising absorption calorie of the glass powder, thereby thermally decomposing with a glass melt having a stable liquid temperature. To recover metal by pyrolyzing metal mixed plastic waste.   In the step of collecting the metal precipitated or dissolved in the glass melt, the metal precipitated in the glass melt is deposited together with the glass melt, and the metal dissolved in the glass melt is deposited on a DC electrode arranged in the glass melt. The method for recovering a metal by thermally decomposing the metal-mixed plastic waste according to claim 1, wherein the metal-mixed plastic waste is recovered together with a glass melt.   In the process of cooling the gas generated by the pyrolysis with water and solidifying and recovering the metal contained in the gas, oxygen is injected to stabilize the active substance contained in the gas by oxidizing and burning while recovering the metal solidified by water cooling of the gas. It is exhausted as a gas with the properties. The metal mixed plastic waste according to claim 1, wherein the metal dissolved in the cooling water by water cooling is recovered by precipitation by neutralizing the cooling water, and the treated water is recovered and reused. A method for recovering metals.   Pyrolysis device that provided a residence space for the generated pyrolysis gas by thermally decomposing metal-mixed plastic waste injected into the stored glass melt, and a precipitated metal recovery device that collects the metal that settles at the bottom of the glass melt And a molten metal recovery device that recovers the metal that dissolves in the glass melt, and the pyrolysis gas was cooled with water and recovered, and the solidified metal was recovered and oxidized and burned with oxygen injected into the active substance contained in the pyrolysis gas. Metal processing is performed by a gas treatment device that exhausts with a property gas, and a water treatment device that collects and dissolves the metal dissolved in cooling water by water cooling and precipitates it by neutralizing the cooling water, and collects and reuses the water after neutralization. A device for recovering metal by thermally decomposing metal-mixed plastic waste, characterized by providing means for recovering and reusing the used water.   In the thermal decomposition apparatus, the amount of heat absorbed by thermal decomposition is replenished with the amount of heat generated by oxidizing and burning the oxygen in the plastic mixed metal waste and the amount of heat generated by the reaction of the composition material of the glass melt with the combustion gas. , The thermal decomposition is performed while adjusting the fluctuation of the replenishment heat amount with the amount of heat retained by the amount of the glass melt, and when the liquid temperature of the glass melt falls during the thermal decomposition, waste plastic is introduced, and the combustion heat amount and combustion of the plastic The liquid temperature is increased by the heat of reaction of the composition material of the glass melt that reacts with the gas. When the liquid temperature of the glass melt increases, the glass powder is added, and the liquid temperature is decreased by the temperature rise absorption heat quantity of the glass powder. 6. The apparatus for thermally decomposing metal mixed plastic waste according to claim 5, wherein the metal is recovered by pyrolysis with a glass melt having a stable liquid temperature.   Among the precipitated metal recovery device and the dissolved metal recovery device, the precipitated metal recovery device discharges and recovers the metal precipitated at the bottom of the glass melt of the thermal decomposition device from the bottom of the thermal decomposition device together with the glass melt. The metal dissolved in the glass melt is deposited on the DC electrode, the anode and cathode of the electrode are peeled off from the switching electrode, and a means for discharging and collecting the glass melt from the bottom of the thermal decomposition apparatus is provided. The apparatus which collects metal by thermally decomposing the metal mixed plastic waste of 5.   Among the gas treatment device and the water treatment device, the gas treatment device oxidizes with active oxygen contained in the pyrolysis gas while recovering the solidified metal by cooling with water in a plurality of cooling tanks connected to the pyrolysis gas. Combust and exhaust with stable gas. 6. The metal-mixed plastic waste according to claim 5, wherein the water treatment device precipitates and recovers the metal dissolved in the cooling water by water cooling and neutralizes the cooling water, and collects and reuses the water after the neutralization treatment. A device that thermally decomposes materials and recovers metals.

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