Plasma high-temperature melting carbonaceous mixed solid waste treatment system and treatment method

Abstract

The application discloses a kind of plasma high-temperature smelting carbonaceous mixed solid waste processing system, processing method;Processing system includes furnace front feeding device, for collecting carbonaceous mixed solid waste;Flotation separation system is used to carry out flotation separation to carbonaceous mixed solid waste to obtain fine carbon powder and impurities;Flash discharge device is used to discharge treatment to fine carbon powder to obtain laminated graphene;Plasma melting system is used to heat smelting treatment to impurities to obtain glass smelting solidified body and heating smelting tail gas;Supplementary combustion device is used to heat smelting tail gas supplementary combustion;Tail gas treatment system is used to purify the gas from supplementary combustion device to obtain purified gas.The application carries out effective flotation to carbonaceous mixed solid waste, can produce high value-added product laminated graphene powder, can effectively solve the problem of carbon-containing solid waste recovery difficulty reduce high-temperature smelting furnace tar coke and greenhouse gas generation, realize high carbon emission reduction.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solid waste environmental protection treatment, and particularly relates to a plasma high-temperature smelting carbonaceous mixed solid waste treatment system. BACKGROUND

[0002] In recent years, the plasma high-temperature smelting technology has shown great advantages in treating solid waste. It is a waste treatment technology with plasma torch as a heat source, which can balance environmental ecological protection and resource recycling. High-temperature plasma pyrolysis generates combustible small molecular substances from organic molecules in solid waste; inorganic substances are smelted to generate stable glass residues. The plasma high-temperature smelting technology is easy to miniaturize, and the smelting products are safe, stable and reliable. It is currently recognized as the most effective and complete green environmental protection solid waste treatment technology.

[0003] At present, various types of domestic and industrial solid waste have complex composition, and the content of carbonaceous waste such as plastic products, sludge, asphalt, rubber and food residues in solid waste has significantly increased. The carbon source in the solid waste inevitably produces greenhouse gases during the smelting process, and the recycling of carbon components in the plasma high-temperature smelting process is limited, and the subsequent treatment of residues is insufficient. Therefore, new technologies need to be developed in the field of plasma high-temperature smelting to promote the resource utilization of garbage solid waste, follow the background of the double carbon target, reduce carbon emissions, and maximize the utilization of carbon resources. SUMMARY

[0004] In order to solve the problems existing in the process of treating carbonaceous mixed solid waste by the plasma high-temperature smelting technology, the present application provides a plasma high-temperature smelting carbonaceous mixed solid waste treatment system and a treatment method, which can be used for difficult-to-treat carbonaceous mixed solid waste. The waste reduction effect is remarkable, and the product components are all non-toxic, harmless and high-value-added products with good performance, which meet the most stringent tail gas emission standards.

[0005] The first object of the present application is to provide a plasma high-temperature smelting carbonaceous mixed solid waste treatment system, comprising:

[0006] A furnace front feeding device is used for collecting carbonaceous mixed solid waste;

[0007] A flotation separation system is used for flotation separation of the carbonaceous mixed solid waste to obtain fine carbon powder and impurities;

[0008] A flash discharge device is used for discharging treatment of the fine carbon powder to obtain laminated graphene;

[0009] A plasma smelting system is used for heating and smelting treatment of the impurities to obtain a glass smelting solidified body and a heating and smelting tail gas;

[0010] A supplementary combustion device is used for supplementary combustion of the heated molten tail gas.

[0011] A tail gas treatment system is used for purifying the gas flowing out from the supplementary combustion device to obtain purified gas.

[0012] In the present application, the carbonaceous mixed solid waste is effectively floated before the plasma high-temperature melting treatment, and the high-value-added product stacked graphene powder is efficiently and quickly obtained by discharging under high temperature and high pressure using the flash discharge technology, effectively solving the problem of difficult recovery of carbon-containing solid waste; at the same time, the carbonaceous mixed solid waste is subjected to flotation separation treatment, reducing the carbon content in the impurities entering the plasma melting system, and fundamentally reducing the generation of tar and coke and greenhouse gases in the high-temperature melting furnace, reducing carbon emissions in the solid waste treatment process, and achieving high carbon emission reduction. The cost of stacked graphene preparation is high, and the present application can also solve the problem of high cost of graphene preparation.

[0013] In an optional embodiment, the flotation separation system comprises a primary crushing device, a primary flotation device and a primary separation device connected in sequence, the primary crushing device is connected to the pre-furnace feeding device, and the primary separation device is connected to the plasma melting system.

[0014] The flotation separation system further comprises a secondary crushing device, a secondary flotation device and a secondary separation device connected in sequence, the secondary crushing device is connected to the primary separation device, and the secondary separation device is connected to the plasma melting system and the flash discharge device.

[0015] In the present application, through the two flotation separation processes, the obtained fine carbon powder meets the requirements to ensure the excellent performance of the obtained stacked graphene; at the same time, the carbon content in the impurities can be effectively reduced to avoid the generation of tar and coke and greenhouse gases in the plasma high-temperature melting process, and the carbon emissions in the solid waste treatment process are reduced.

[0016] In an optional embodiment, the plasma melting system comprises a plasma high-temperature melting furnace, a plasma torch, a screw hopper and a centrifugal graphite crucible.

[0017] A plurality of plasma torches are arranged on the side wall of the plasma high-temperature melting furnace.

[0018] The screw hopper is connected to the primary separation device and the secondary separation device.

[0019] The bottom of the centrifugal graphite crucible is connected to a slag discharge channel, and an electric resistance wire heating coil device is arranged in the slag discharge channel.

[0020] The outlet of the plasma high-temperature melting furnace is connected to the supplementary combustion device.

[0021] In the present application, the centrifugal graphite crucible can make the non-carbon solid waste fully pyrolyzed in the combustion process, thereby reducing the amount of air required to be introduced into the plasma high-temperature melting furnace, and reducing the energy consumption of solid waste treatment.

[0022] In an optional embodiment, a compressed air tank is connected to the air inlet of the supplementary combustion device to supplement air into the supplementary combustion device.

[0023] The outlet of the compressed air tank is also connected to the plasma high-temperature melting furnace.

[0024] In the present application, compressed air is introduced into the supplementary combustion device to fully combust the heated and melted tail gas; at the same time, compressed air is introduced into the plasma high-temperature melting furnace as the working gas of the plasma high-temperature melting furnace, realizing long-period stable operation of the entire system, prolonging the service life of the equipment, and reducing the cost.

[0025] In an optional embodiment, the outlet of the supplementary combustion device is also connected to a particle collection device, and the outlet of the particle collection device is connected to the inlet of the primary flotation device.

[0026] In the present application, the particle collection device filters out the particle impurities in the fly ash generated in the supplementary combustion process and sends them back to the flotation device for flotation, which can realize maximum resource recycling.

[0027] In an optional embodiment, the tail gas treatment system comprises a tail gas cooling and purification device and a chimney connected in sequence, and a pollution monitor is arranged on the chimney.

[0028] In the present application, the waste gas is cooled and purified, which can effectively reduce the content of pollutants in the tail gas and achieve the goal of clean emission.

[0029] In an optional embodiment, the rear end of the flash discharge device is sequentially connected to an electrode material preparation system and an electrode replacement device, and the rear end of the electrode replacement device is connected to the plasma torch.

[0030] The electrode material preparation system is used to process the incoming laminated graphene into torch anode material and torch cathode material, and to deliver the electrode material to the electrode replacement device.

[0031] The electrode replacement device is used to transport the torch anode material and the torch cathode material to the plasma torch, and to disassemble the old electrode on the plasma torch to replace the new electrode, so as to realize the self-supply of the torch electrode.

[0032] Since in the prior art, the plasma torch electrode generally adopts copper anode and tungsten cathode, the electrode material will gradually deteriorate under the long-time high-temperature plasma erosion, so its service life is limited, and manual electrode replacement is required at regular intervals, which seriously affects the solid waste treatment efficiency. At present, in the face of large-capacity solid waste treatment conditions, a large-power plasma torch is needed for long-time heating, which requires longer service life, lower cost and more convenient maintenance and replacement of the torch electrode, so as to improve the efficiency of solid waste treatment and the economy of the melting system. In the present application, the product graphene is processed to form a torch electrode material, which meets the consumption demand of the plasma torch itself and realizes self-supply of the torch electrode. Compared with the traditional copper anode and tungsten cathode materials, the self-supplied electrode material formed by utilizing carbonaceous waste has more excellent ablation resistance, solves the problems of large consumption and short service life of the plasma torch electrode, and greatly improves the economy of the melting system. In the present application, the electrode replacement device is used to realize automatic replacement and maintenance of the torch electrode, which greatly reduces the labor cost and effectively improves the safety and operability of the system.

[0033] In an optional embodiment, the torch anode material is a graphene / copper-based composite material, and the torch cathode material is a graphene / bitumen-based material.

[0034] The torch anode material is prepared from activated laminated graphene, copper powder and niobium powder as raw materials, and the mass ratio is (3-5):(80-90):(3-5).

[0035] The torch cathode material is prepared from activated laminated graphene and refined carbon powder obtained by a flotation separation system as raw materials, and the mass ratio is (1-2):(90-95).

[0036] The graphene-reinforced torch electrode material of the present application has more excellent ablation resistance, is suitable for large-capacity solid waste treatment in a high-power plasma high-temperature melting system, the service life of the torch electrode is improved, and long-time and economic operation of the system can be realized.

[0037] A second object of the present application is to provide a treatment method of a plasma high-temperature melting carbonaceous mixed solid waste treatment system, comprising:

[0038] (1) obtaining refined carbon powder and impurities from carbonaceous mixed solid waste by flotation separation;

[0039] (2) discharging the refined carbon powder to obtain laminated graphene;

[0040] (3) heating and melting the impurities to obtain a glass melting solidified body and a heating and melting tail gas;

[0041] (4) supplementally combusting the heating and melting tail gas;

[0042] (5) purifying the gas after the supplemental combustion to obtain a purified gas.

[0043] In an optional embodiment, the process of step (1) is:

[0044] The mixed solid waste in the front-end feeding device is crushed by the primary crushing device to obtain primary waste residue, the primary waste residue is floated by the primary flotation device to obtain primary slurry, and the primary slurry is separated by the primary separation device to obtain carbon residue and impurities;

[0045] The carbon residue is crushed by the secondary crushing device to obtain secondary waste residue, the secondary waste residue is floated by the secondary flotation device to obtain secondary slurry, and the secondary slurry is separated by the secondary separation device to obtain fine carbon powder and impurities;

[0046] The waste residue is subjected to humidification treatment in both the primary and secondary flotation processes;

[0047] The slurry concentration is adjusted to 25-35% during the two humidification treatments, the rotation speed is 1800-2000 r / min during the two flotation processes, the flotation time is 10-15 minutes, and the foam is scraped every 10 seconds;

[0048] The carbon content of the carbonaceous waste in the mixed solid waste is greater than 90%.

[0049] In an optional embodiment, the discharge treatment conditions of the fine carbon powder in step (2) are: discharge voltage 400-450 V, discharge time 300-400 ms, sample tube wall temperature less than 60°C during discharge, argon gas is injected into the tube to promote the discharge process, and the core temperature of the discharge area is less than or equal to 3000K.

[0050] In an optional embodiment, in step (4), the heated and melted tail gas is fully combusted by the supplemental combustion device, and the fly ash generated is returned to the primary flotation device for flotation treatment by the particle collection device;

[0051] In step (5), after the gas after the supplemental combustion is subjected to deacidification, demisting, and cooling and purification treatment by the tail gas cooling and purification device, it is introduced into the chimney by the induced draft fan for discharge;

[0052] In step (3), the compressed air in the compressed air tank enters the plasma high-temperature melting furnace;

[0053] In step (4), the compressed air in the compressed air tank enters the supplemental combustion device.

[0054] In an optional embodiment, it also includes preparing a torch anode material and a torch cathode material, and placing the torch anode material and the torch cathode material together in an electrode replacement device, the electrode replacement device pulls out the plasma torch to remove the old electrode, and installs the electrode material into the plasma torch.

[0055] In an optional embodiment, the preparation process of the torch anode material is as follows:

[0056] The graphene powder in step (2) is subjected to activation treatment;

[0057] The graphene powder after activation treatment, copper powder and niobium powder are added into ethanol solution in a mass ratio of (3-5):(80-90):(3-5) for oscillation and dissolution to obtain a dispersion liquid of mixed powder;

[0058] The dispersion liquid is ball milled and dried to obtain dry mixed powder;

[0059] The mixed powder is subjected to spark plasma sintering at 700 DEG C for 5-10 minutes in vacuum, and then cooled, molded and shaped, and the pressure is gradually increased to 50-60 MPa at a rate of 0.1 MPa per minute until the end of cooling to obtain a rod-shaped graphene / copper-based composite material;

[0060] The preparation process of the torch cathode material is as follows:

[0061] The graphene powder in step (2) is subjected to activation treatment, and the refined carbon powder separated from step (1) is used as raw material, and the mass ratio of the graphene powder to the refined carbon powder is (1-2):(90-95), which is put into a ball milling device;

[0062] After ball milling, kneading is carried out, and liquid pitch is added during kneading, and the mass ratio of the pitch to the refined carbon powder is 1:2;

[0063] After kneading, the paste is put into a tabletting device for processing, and the preform is obtained by cold molding at 150 MPa for 3-6 minutes in an isostatic pressing device;

[0064] The preform is placed into a sintering device at 1100 DEG C for vacuum sintering for 120 hours to obtain a rod-shaped graphene / pitch-based material.

[0065] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0066] (1) The plasma high-temperature molten carbonaceous mixed solid waste treatment system provided by the embodiment of the present application can effectively float the carbonaceous mixed solid waste before plasma high-temperature molten treatment, and then discharge under high temperature and high pressure by using flash discharge technology, so that high-value-added product laminated graphene powder can be obtained efficiently and quickly, and the problem of difficult recovery of carbon-containing solid waste is effectively solved.

[0067] (2) The flotation separation treatment of the carbonaceous mixed solid waste can fundamentally reduce the generation of tar and coke and greenhouse gases in the high-temperature melting furnace, reduce the carbon emission in the solid waste treatment process, and achieve high carbon emission reduction.

[0068] (3) The preparation cost of the stacked graphene is high, and the graphene preparation cost problem can be solved by the application.

[0069] (4) The product graphene is processed to prepare a torch electrode material, which meets the consumption demand of the plasma torch itself, and realizes self-supply of the torch electrode. Compared with the traditional copper anode and tungsten cathode material, the self-supplied electrode material formed by utilizing carbonaceous waste has more excellent ablation resistance, which effectively solves the problems of large consumption and short service life of the plasma torch electrode, and greatly improves the economy of the melting system. The electrode replacement device is adopted to realize automatic torch electrode replacement and maintenance, greatly reducing the labor cost, and effectively improving the safety and operability of the system. BRIEF DESCRIPTION OF DRAWINGS

[0070] In order to more clearly illustrate the technical solutions of the example embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor. In the drawings:

[0071] Figure 1 A schematic diagram of a plasma high-temperature melting carbonaceous mixed solid waste treatment system provided by the embodiment of the application;

[0072] Figure 2 A structural schematic diagram of a flash discharge device provided by the embodiment of the application;

[0073] Figure 3 A preparation flowchart of the torch anode material;

[0074] Figure 4 A preparation flowchart of the torch cathode material.

[0075] The components in the drawings and the corresponding labels are:

[0076] 1-plasma high-temperature melting furnace; 2-plasma torch; 3-spiral hopper; 4-centrifugal graphite crucible; 5-resistance wire heating coil device; 6-complementary combustion device; 7-tail gas cooling and purification device; 8-chimney; 9-compressed air tank; 10-particle collection device; 11-pollution monitor; 12-furnace front feeding device; 13-primary crushing device; 14-primary flotation device; 15-primary separation device; 16-secondary crushing device; 17-secondary flotation device; 18-secondary separation device; 19-flash discharge device; 20-electrode material preparation system; 21-electrode replacement device. DETAILED DESCRIPTION

[0077] In order to make the objects, technical solutions and advantages of the present application clearer, further detailed description will be made to the present application in combination with embodiments and drawings, the illustrative embodiments and the description thereof are only used to explain the present application and not as limitation to the present application.

[0078] In the following description, a large number of specific details are set forth to provide a thorough understanding of the present application. However, it will be apparent to one of ordinary skill in the art that the present application can be practiced without these specific details. In other instances, well-known structures, circuits, materials or processes have not been described in detail in order to avoid obscuring the present application.

[0079] Throughout the specification, reference to "one embodiment", "an embodiment", "one example" or "an example" means that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the application. The appearances of the phrases "in one embodiment", "an embodiment", "in one example" or "an example" in various places in the specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics can be combined in any suitable

[0080] Embodiment 1:

[0081] As shown in Figure 1 A plasma high-temperature melting carbonaceous mixed solid waste treatment system, the system comprises:

[0082] A pre-furnace feeding device 12 for collecting carbonaceous mixed solid waste, the carbon content in the carbonaceous mixed solid waste should be greater than 90%, and the high-carbon-content mixed solid waste is, for example, coal, petroleum coke, biochar and carbon black.

[0083] A flotation separation system for flotation separation of the carbonaceous mixed solid waste to obtain fine carbon powder and impurities; the flotation separation system comprises two times of flotation separation devices, specifically comprising:

[0084] A primary crushing device 13, a primary flotation device 14 and a primary separation device 15 connected in sequence, the primary crushing device 13 is connected to the pre-furnace feeding device 12, and the primary separation device 15 is connected to the plasma melting system; the carbonaceous mixed solid waste is crushed, floated and separated in sequence to obtain carbon residue and impurities;

[0085] The secondary crushing device 16, the secondary flotation device 17 and the secondary separation device 18 are sequentially connected, the secondary crushing device 16 is connected with the primary separation device 15, and the secondary separation device 18 is connected with the plasma melting system and the flash discharge device 19. The carbon residue is sequentially subjected to crushing, flotation and separation to obtain fine carbon powder and impurities; the fine carbon powder is subjected to high-temperature and high-pressure discharge treatment to obtain laminated graphene, and the impurities are subjected to plasma high-temperature melting treatment.

[0086] It should be known by those skilled in the art that the flotation separation process in the embodiment of the present application is not limited to twice, and can be adjusted as required.

[0087] The flash discharge device 19 is used for discharging the fine carbon powder to obtain laminated graphene. The flash discharge device 19 specifically comprises a copper electrode, a quartz sample tube, a wire, a switch and a discharge device group. The specific connection mode and working principle of the copper electrode, the quartz sample tube, the wire, the switch and the discharge device group are known technologies. The quartz sample tube has a diameter of 5 cm, and the gas pressure in the tube is normal pressure.

[0088] The plasma melting system is used for heating and melting the impurities to obtain a glass melting solidified body and a heating and melting tail gas. The plasma melting system comprises a plasma high-temperature melting furnace 1, a plasma torch 2, a spiral hopper 3 and a centrifugal graphite crucible 4.

[0089] The impurities screened out by the primary separation device 15 and the secondary separation device 18 are connected with the spiral hopper 3 through a conveying channel. The spiral hopper 3 is arranged at the top of the plasma high-temperature melting furnace 1 and is used for feeding the impurity solid waste into the plasma high-temperature melting furnace 1. A plurality of plasma torches 2 are arranged at the center of the inside of the plasma high-temperature melting furnace 1. The plasma torches 2 are arranged on the sidewall of the furnace body outside the hearth at an installation height and an inclination angle, so that the plasma torches 2 can directly heat the materials in the molten pool body. The plasma high-temperature melting furnace 1 is internally provided with a centrifugal graphite crucible 4. The centrifugal graphite crucible 4 can withstand high temperature and high pressure, and can uniformly and sufficiently heat the waste materials when rotating. The bottom of the centrifugal graphite crucible 4 is provided with a slag discharge channel for discharging the waste slag after the solid pollutants are burned. The slag discharge channel comprises a resistance wire heating coil device 5, which can heat the high-temperature glass body at the slag discharge port to prevent the glass body from solidifying and blocking the external discharge channel. In addition, a high-temperature lining is arranged in the plasma high-temperature melting furnace 1, and a water supply system is arranged for heat protection during the melting process. The plasma torch 2 can be a direct current transferred arc or a non-transferred arc plasma torch generator, an alternating current transferred arc or a non-transferred arc plasma torch 2.

[0090] The combustible gas outlet of the plasma high-temperature melting furnace 1 is communicated with the combustible gas inlet of the supplementary combustion device 6 through a pipeline; the supplementary combustion device is used for supplementary combustion of the heated melting tail gas; a compressed air tank 14 is communicated with the air inlet of the supplementary combustion device 6, and is used for combustion of the waste gas and air to generate tail gas;

[0091] The outlet of the compressed air tank 9 is also connected with the plasma high-temperature melting furnace 1 and the supplementary combustion device 6; a part of the gas of the compressed air tank 9 can be directly pumped into the plasma high-temperature melting furnace 1 and the supplementary combustion device 6;

[0092] The outlet of the supplementary combustion device 6 is also connected with a particle collection device 10, and the particle collection device 10 is connected with the primary flotation device 14, so as to collect the fly ash particles generated in the supplementary combustion process and throw back the fly ash to the primary flotation device 14 for resource recycling.

[0093] The tail gas treatment system is used for purifying the gas flowing out from the supplementary combustion device to obtain purified gas; the tail gas treatment system comprises a tail gas cooling and purification device 7 and a chimney 8 connected in sequence; a pollution monitor 11 is arranged on the chimney 8.

[0094] The treatment system further comprises electrode material preparation systems 20 and 21 connected in sequence, the electrode material preparation system 20 is connected at the rear end of the flash discharge device 19, and the rear end of the electrode replacement device is connected with the plasma torch; the electrode material preparation system is used for processing the entering laminated graphene into torch anode material and torch cathode material, and conveying the electrode material to the electrode replacement device; the electrode material preparation system comprises an ultrasonic device for preparing torch anode material, a ball milling device, a drying device, a spark plasma sintering device, and further comprises a kneading device, a sheet rolling device, an isostatic pressing device and a sintering device for preparing torch cathode material, and each device can adopt existing commercial products. The electrode replacement device is used for conveying the torch anode material and the torch cathode material to the plasma torch, and disassembling the old electrode on the plasma torch to replace the new electrode, so as to realize the self-supply of the torch electrode. The electrode replacement device internally comprises a feeding bin, a discharging bin, a clamping mechanism and a driving mechanism, and can realize the automatic torch electrode replacement function: the plasma torch replacement system produced by Sichuan Huaobao Xiang Technology Co., Ltd. can be adopted, and the mechanical arm of model IRB 6700-150 can realize the disassembly of the old electrode and the installation of the new electrode, and after the electrode installation is completed, the plasma torch 2 is reinstalled to the corresponding position of the plasma high-temperature melting furnace 1. A plurality of plasma torches 2 can also be arranged in the supplementary combustion device 6 for combustion of the waste gas and air to generate tail gas, and the electrode replacement device can also replace and install the electrodes on the plasma torches 2 in the supplementary combustion device 6.

[0095] Example 2:

[0096] The method for processing the carbonaceous mixed solid waste by using the processing system of Example 1 is as follows:

[0097] (1) The carbonaceous mixed solid waste is separated by flotation to obtain refined carbon powder and impurities;

[0098] (2) The refined carbon powder is subjected to discharge treatment to obtain laminated graphene;

[0099] (3) The impurities are subjected to heating and melting to obtain a glass melting solidified body and a heating and melting tail gas;

[0100] (4) The heating and melting tail gas is subjected to supplemental combustion treatment;

[0101] (5) The gas after supplemental combustion is subjected to purification treatment to obtain purified gas.

[0102] The detailed process is as follows:

[0103] S1: The carbonaceous mixed solid waste is fed into the pre-furnace feeding device 12, and the carbon content of the carbonaceous waste in the mixed solid waste should be greater than 90%, including mixed solid waste with high carbon content, such as coal, petroleum coke, biochar and carbon black, etc. The mixed solid waste in the pre-furnace feeding device 12 is crushed by entering the primary crushing device 13, and the primary waste residue generated by crushing enters the primary flotation device 14 for primary flotation.

[0104] S2: The solid waste in the above flotation device is humidified. When the slurry concentration is lower than 25%, the bubbles are slow and the flotation speed is low; when the slurry concentration is higher than 35%, the grade and recovery rate of the floated carbon material decrease, so the slurry concentration is adjusted to 25-35% by humidification. Considering the good floatability of carbon, 500g / t of depressant water glass is added, and the stirring time is 3-5min; 320g / t of collector kerosene is added, and the stirring time is 1-2min. The flotation is carried out for 10-15 minutes under the condition that the rotation speed of the flotation machine is 1800-2000r / min, and the bubbles are scraped every 10s. When the rotation speed is lower than 1800r / min, the recovery rate of carbon material is lower; when the rotation speed is higher than 2000r / min, the recovery rate remains basically unchanged, so the rotation speed of the flotation machine is taken as 1800-2000r / min, and the quality of the flotation product is better under this rotation speed.

[0105] S3, the primary slurry generated in the above step is separated into carbon residue and impurities by the primary separation device 15, the carbon residue enters the secondary crushing device 16, and after crushing, 90% of the carbon residue is crushed to 200 mesh, which is beneficial to the secondary flotation of high-purity refined carbon, and the carbon residue enters the secondary flotation device 17 for secondary flotation. The secondary flotation process is the same as step S2.

[0106] S4. The secondary slurry produced in the above steps is fed into the secondary separation device 18 to separate refined carbon powder and impurities. The refined carbon powder then enters the flash discharge device 19 for discharge. The flash discharge device 19 specifically includes: copper electrodes, a quartz sample tube, wires, a switch, and a discharge assembly. Positive and negative electrodes are connected to both ends of the sample tube, which is placed inside the discharge assembly. The connecting wires of the positive and negative electrodes are connected to the switch. See [link to relevant documentation]. Figure 2 As shown.

[0107] S5. Place the refined carbon powder produced in step S4 above into a quartz sample tube with a diameter of 5 cm, and maintain atmospheric pressure inside the tube. Connect positive and negative electrodes to both ends of the sample tube, and use a discharge apparatus to perform high-voltage discharge on the powder. The discharge voltage is 400-450V, which ensures that the surface temperature of the carbon source reaches above 2500K during discharge, thereby exfoliating the multilayered graphene. The discharge time is 300-400ms, and the temperature of the sample tube wall is less than 60℃ during discharge. Inert argon gas is introduced into the tube to promote the discharge process, and the core temperature of the discharge region does not exceed 3000K. After discharge, remove the reactants, wash, filter, and dry them repeatedly to obtain multilayered graphene powder.

[0108] S6. The graphene powder produced in step S5 is activated (the specific activation process uses existing technology, which will not be described in detail here). The active groups grafted onto the activated graphene can prevent agglomeration. The activated graphene powder, copper powder, and niobium powder are added to an ethanol solution in a mass ratio of 3-5:80-90:3-5 (within this ratio range, graphene has good dispersibility). The mixture is then thoroughly shaken in an ultrasonic device for 15-30 minutes. The dispersion of the mixed powder is ball-milled for 0.5-1 hours to ensure uniform dispersion of the powder. After ball milling, a mixed liquid is obtained. The mixed liquid is heated in a water bath to 80°C with continuous stirring until it becomes semi-dry. Then, it is placed in a drying oven to dry, obtaining a dry mixed powder. The mixed powder is sintered in a vacuum at 700°C using spark plasma for 5-10 minutes. At the beginning of cooling, the pressure is gradually increased to 50-60 MPa at a rate of 0.1 MPa per minute from 40 MPa until cooling is complete. After cooling, rod-shaped graphene / copper-based composite materials (i.e., torch anode materials) are obtained. The preparation process of the torch anode materials is described below. Figure 2 .

[0109] S7. After activating the graphene powder produced in step S5, it is placed together with the refined carbon powder separated in step S3 into a ball mill. The mass ratio of graphene powder to refined carbon powder is 1-2:90-95 (within this ratio range, the graphene powder has good dispersibility in the matrix). After ball milling for 0.5-1 hours, the mixed powder is placed into a kneading device and kneaded evenly for 1-1.5 hours. During the kneading process, liquid asphalt is added as a binder. Liquid asphalt is beneficial for the adhesion between carbon components and reduces the porosity of the matrix. The mass ratio of asphalt to refined carbon powder is 1:2. Adding asphalt in this mass ratio is beneficial for bonding different carbon particles and coating graphene, so that it is evenly dispersed in the matrix. After kneading, the paste is fed into a rolling mill to increase material density. Then, the aggregate is placed in an isostatic pressing apparatus and cold-molded at 150 MPa for 3-6 minutes to obtain a preform. The preform is then placed in a sintering apparatus at 1100℃ and vacuum-sintered for 120 hours to obtain rod-shaped graphene / asphalt-based material (i.e., torch cathode material). The preparation process of the torch cathode material is described in [link to documentation]. Figure 3 .

[0110] S8. Place the torch anode material obtained in step S6 and the torch cathode material obtained in step S7 into the electrode replacement device 21. The electrode replacement device 21 automatically pulls out the plasma torch 2, removes the old electrode, and installs the electrode materials obtained in steps S6 and S7 into the plasma torch 2. Then, the plasma torch 2 is installed back in its original position.

[0111] Other impurities separated by flotation in steps S9, S3, and S4 directly enter the spiral hopper 3 of the plasma high-temperature melting furnace 1, while solid waste falls into the separate graphite crucible 4. The impurities and waste are heated and melted using the plasma torch 2, while the compressed air tank 9 injects gas into the plasma melting furnace to promote melting. The size of the centrifugal zone formed by the molten liquid of the solid pollutants is controlled by controlling the rotation speed of the centrifugal graphite crucible 4. The molten liquid of the solid pollutants is controlled to flow out from the slag outlet at the bottom of the crucible. The resistance wire heating coil device 5 at the slag outlet is surrounded by the main body outside the slag discharge channel. Heating enhances the fluidity of the inorganic glass melt, allowing it to be discharged. At the same time, waste gas is generated during melting in the furnace.

[0112] The exhaust gas generated in steps S10 and S9 enters the supplementary combustion device 6. The compressed air tank 9 injects gas into the supplementary combustion device 6 to promote complete combustion and generate exhaust gas. The fly ash generated by the supplementary combustion device 6 is returned to the primary flotation device 14 through the particle collection device 10. The exhaust gas generated by the supplementary combustion device 6 enters the exhaust gas cooling and purification device 7 through the pipeline.

[0113] In steps S11 and S10, the flue gas enters the exhaust gas cooling and purification device 7 for deacidification, demisting, cooling and purification treatment, and then is introduced into the chimney 8 for exhaust gas emission.

[0114] In step S9, a non-toxic and harmless inorganic solidified glass body is produced from the slag discharge port after being heated by a resistance wire heating coil; in step S11, the flue gas is discharged after being monitored and qualified by the pollution monitor 11, thus completing the entire process of plasma high-temperature melting for the treatment of carbonaceous mixed solid waste.

[0115] The anode and cathode materials prepared in the above embodiments were subjected to ablation tests and compared with multiple actual comparative examples.

[0116] Density was tested using a precision density meter (manufacturer: Shenzhen Dahong Meituo Density Measurement Instrument Co., Ltd., model: DH-300), and the melting point was tested using a melting point meter (manufacturer: Xiangtan Huafeng Instrument Manufacturing Co., Ltd., model: GFT-160). Arc ablation tests were conducted using an electrode ablation testing device (manufacturer: Beijing Jingke Zhichuang Technology Development Co., Ltd., model: AE-300). The ablation rate testing and calculation methods are as follows:

[0117] A graphene / copper composite material was used as the ablation anode, and a graphene / asphalt-based material was used as the ablation cathode. An arc ablation experiment with a DC current of 80A was conducted, with tests performed at three time points. The ablation amount was calculated as the average mass difference before and after the ablation in the three experiments. A Hall effect sensor was used to collect the arc current during the experiment, and the charge value was calculated using the following formula:

[0118]

[0119] In the formula, Q is the transferred charge, in C; T is the arcing time, in s; and i is the arc current, in A.

[0120] The ablation rate is characterized by the ratio of electrode material loss to charge transfer, and is calculated as follows:

[0121]

[0122] In the formula, m0 and m1 are the masses of the electrode material before and after erosion, in mg; Q is the transferred charge, in C; and η is the ablation rate of the material, in mg·C. -1 .

[0123] The data obtained from the experiment are shown in Table 1:

[0124] Table 1: Test Comparison Results

[0125]

[0126] As shown in Table 1, the graphene / copper composite material used as the torch anode in the embodiments has a lower density. The addition of graphene gives the material a slight advantage in thermal conductivity. Carbon has a higher melting point than copper. Therefore, the embodiments of the present invention have a lower ablation rate and better ablation resistance compared to the pure copper anode material of the comparative example (commercially available industrial grade). The embodiments also use graphene / pitch-based material as the torch cathode, which has a lower density and a higher melting point. Compared to the tungsten cathode material of the comparative example (commercially available industrial grade), the pitch-based carbon material itself has a higher melting point than tungsten, and graphene exhibits superior thermal conductivity within the matrix, preventing ablation and the formation of a molten pool due to excessively high temperatures at a single point. Therefore, the graphene / pitch-based material has a lower ablation rate and better ablation resistance.

[0127] In summary, by utilizing the self-supplying plasma high-temperature melting system with ablation-resistant electrodes proposed in this invention (i.e., the plasma high-temperature melting carbonaceous mixed solid waste treatment system), carbonaceous solid waste is effectively separated by flotation. The resulting graphene-reinforced torch electrode material exhibits superior ablation resistance, making it suitable for high-power plasma high-temperature melting systems to treat large volumes of solid waste. The torch electrode lifespan is extended, enabling long-term, economical system operation. Furthermore, the treatment system of this invention can be used for difficult-to-treat carbonaceous mixed solid waste, achieving significant volume and weight reduction. The products are all non-toxic, harmless, and high-value-added products with excellent performance, meeting the most stringent exhaust emission standards.

[0128] Unless otherwise specified, the methods, processes, and apparatus involved in this invention are all based on existing technology or commercially available instruments and equipment.

[0129] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A plasma high-temperature molten carbonaceous mixed solid waste treatment system, characterized in that, include: The furnace feed device is used to collect carbonaceous mixed solid waste; A flotation separation system is used to separate carbonaceous mixed solid waste by flotation to obtain refined carbon powder and impurities; A flash discharge device is used to discharge-treat the refined carbon powder to obtain multilayer graphene. A plasma melting system is used to heat and melt the impurities to obtain a glass molten solid and a heating and melting exhaust gas; A supplementary combustion device is used to supplement the combustion of heated and molten exhaust gas; The exhaust gas treatment system is used to purify the gas flowing out from the supplementary combustion device to obtain purified gas; The flotation separation system includes a primary crushing device, a primary flotation device, and a primary separation device connected in sequence. The primary crushing device is connected to the furnace feed device, and the primary separation device is connected to the plasma melting system. The flotation separation system further includes a secondary crushing device, a secondary flotation device, and a secondary separation device connected in sequence. The secondary crushing device is connected to the primary separation device, and the secondary separation device is connected to the plasma melting system and the flash discharge device. The plasma melting system includes a plasma high-temperature melting furnace, a plasma torch, a spiral hopper, and a centrifugal graphite crucible; Multiple plasma torches are tilted and arranged on the side wall of the plasma high-temperature melting furnace; The spiral hopper is connected to the primary separation device and the secondary separation device; The centrifugal graphite crucible is placed inside a plasma high-temperature melting furnace, and the bottom of the centrifugal graphite crucible is connected to a slag discharge channel, which is equipped with a resistance wire heating coil device. The outlet of the plasma high-temperature melting furnace is connected to the supplementary combustion device; The flash discharge device is sequentially connected to an electrode material preparation system and an electrode replacement device at its rear end, and the rear end of the electrode replacement device is connected to the plasma torch. The electrode material preparation system is used to process the incoming stacked graphene into torch anode material and torch cathode material, and to transport the electrode material to the electrode replacement device. The electrode replacement device is used to transport the torch anode and cathode materials to the plasma torch and to remove the old electrodes on the plasma torch to replace them with new electrodes, so as to enable the torch electrode self-supply.

2. The plasma high-temperature molten carbonaceous mixed solid waste treatment system according to claim 1, characterized in that, The air inlet of the supplementary combustion device is connected to a compressed air tank to supplement air into the supplementary combustion device; The outlet of the compressed air tank is also connected to the plasma high-temperature melting furnace.

3. The plasma high-temperature molten carbonaceous mixed solid waste treatment system according to claim 1, characterized in that, The outlet of the supplementary combustion device is also connected to a particle collection device, and the outlet of the particle collection device is connected to the inlet of the primary flotation device.

4. The plasma high-temperature molten carbonaceous mixed solid waste treatment system according to claim 1, characterized in that, The exhaust gas treatment system includes an exhaust gas cooling and purification device and a chimney connected in sequence. The exhaust gas cooling and purification device is connected to the supplementary combustion device, and a pollution monitor is installed on the chimney.

5. The plasma high-temperature molten carbonaceous mixed solid waste treatment system according to claim 1, characterized in that, The torch anode material is a graphene / copper-based composite material, and the torch cathode material is a graphene / asphalt-based material; The torch anode material is prepared from activated multilayer graphene, copper powder, and niobium powder as raw materials, in a mass ratio of (3-5):(80-90):(3-5); The torch cathode material is prepared from activated multilayer graphene and refined carbon powder obtained by flotation separation system as raw materials, in a mass ratio of (1-2):(90-95).

6. A method for treating carbonaceous mixed solid waste using a plasma high-temperature melting carbonaceous mixed solid waste treatment system as described in any one of claims 1 to 5, characterized in that, include: (1) Carbonaceous mixed solid waste is separated by flotation to obtain refined carbon powder and impurities; (2) The refined carbon powder was subjected to discharge treatment to obtain multilayer graphene; (3) The impurities are heated and melted to obtain a glass melt solidified body and a heating and melting tail gas; (4) Perform supplementary combustion treatment on the heated and molten exhaust gas; (5) Purify the gas after supplementary combustion to obtain purified gas.

7. The method as described in claim 6, characterized in that, The process of step (1) is as follows: The mixed solid waste in the furnace feed device is crushed by a primary crushing device to obtain primary waste residue. The primary waste residue is floated by a primary flotation device to obtain primary slurry. The primary slurry is separated by a primary separation device to obtain carbon slag and impurities. The carbon slag is crushed by a secondary crushing device to obtain secondary waste residue, which is then floated by a secondary flotation device to obtain secondary slurry. The secondary slurry is then separated by a secondary separation device to obtain refined carbon powder and impurities. The waste residue was humidified during both flotation processes; During both humidification treatments, the slurry concentration was adjusted to 25-35%. During both flotation processes, the rotation speed was 1800-2000 r / min, and the flotation time was 10-15 minutes, with the bubbles being scraped off every 10 seconds. The carbonaceous waste in the mixed solid waste contains more than 90% carbon.

8. The method as described in claim 6, characterized in that, The conditions for the discharge treatment of refined carbon powder in step (2) are: discharge voltage 400-450V, discharge time 300-400ms, sample tube wall temperature less than 60℃ during discharge, argon gas is injected into the tube to promote the discharge process, and the core temperature of the discharge zone is less than or equal to 3000K.

9. The method as described in claim 6, characterized in that, In step (4), the heated molten tail gas is fully combusted by the supplementary combustion device, and the resulting fly ash is returned to the primary flotation device for flotation treatment by the particle collection device. In step (5), the gas after combustion is treated by the exhaust gas cooling and purification device to remove acid and mist, and then introduced into the chimney by the induced draft fan for emission. In step (3), compressed air from the compressed air tank enters the plasma high-temperature melting furnace; In step (4), compressed air from the compressed air tank enters the supplementary combustion device.

10. The method as described in claim 6, characterized in that, It also includes preparing torch anode and torch cathode materials, placing the torch anode and torch cathode materials together into an electrode replacement device, removing the old electrodes from the plasma torch, and installing the electrode materials into the plasma torch.

11. The method as described in claim 10, characterized in that, The preparation process of the torch anode material is as follows: The graphene powder in step (2) is activated. The activated graphene powder, copper powder and niobium powder were added to an ethanol solution in a mass ratio of (3-5):(80-90):(3-5) and shaken to dissolve, thus obtaining a dispersion of the mixed powders. The dispersion was ball-milled and then dried to obtain a dry mixed powder; The mixed powder was sintered in a vacuum at 700°C using spark plasma for 5-10 minutes, cooled, and molded. The pressure was gradually increased from 40 MPa to 50-60 MPa at a rate of 0.1 MPa per minute until the cooling was completed, resulting in rod-shaped graphene / copper-based composite material. The preparation process of the torch cathode material is as follows: The graphene powder in step (2) is activated and used as raw material with the refined carbon powder separated in step (1). The mass ratio of graphene powder to refined carbon powder is (1-2):(90-95). The graphene powder is then placed in a ball mill. After ball milling, the mixture is kneaded, and liquid asphalt is added during kneading. The mass ratio of asphalt to refined carbon powder is 1:

2. After mixing, the paste is fed into a rolling mill for processing, and then placed into an isostatic pressing device for cold molding at 150MPa pressure for 3-6 minutes to obtain a preform. The preform was placed in a sintering apparatus at 1100℃ and vacuum sintered for 120 hours to obtain rod-shaped graphene / asphalt-based material.

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