High-chlorine solid waste treatment method and device based on air pressure baking

Abstract

The application provides a high-chlorine solid waste treatment method and device based on pressure baking, and belongs to the field of solid waste disposal. The method is specifically as follows: high-chlorine solid waste is subjected to pressure baking at 250 DEG C to 400 DEG C, so that the high-chlorine solid waste is converted into baked coke, volatile matter and hydrogen chloride, and then the hydrogen chloride is absorbed to realize high-chlorine solid waste treatment. The application utilizes the pressure baking mode to treat high-chlorine solid waste, can realize efficient removal of chlorine at a lower temperature, and has higher dechlorination efficiency compared with atmospheric pyrolysis dechlorination, so that higher dechlorination efficiency is obtained while reducing treatment energy consumption, and is suitable for various types of high-chlorine solid waste. Meanwhile, the method can also obtain clean and high-quality baked coke, so that high-chlorine solid waste is deoxidized and upgraded, chlorine is released in the form of HCl at a lower temperature, the difficulty of subsequent chlorine removal is reduced, and reliability is enhanced.

Description

Technical Field

[0001] This invention belongs to the field of solid waste disposal, and more specifically, relates to a method and apparatus for treating high-chlorine solid waste based on air pressure baking. Background Technology

[0002] The annual production of high-chlorine solid waste, including waste plastics (PVC, etc.), rubber, and biomass (straw, etc.), is increasing rapidly, posing a significant challenge to its harmless treatment in my country. Plastics can contain 33%-56% chlorine, rubber waste approximately 30%-40%, and the introduction of large amounts of inorganic chlorine disinfectants and the presence of plastic components (such as PVC) during the disinfection of medical waste can result in chlorine contents of 4.56%-7.52%. When using thermochemical treatment technologies (such as incineration and gasification) to treat these high-chlorine solid wastes, chlorine-containing products such as HCl and chlorobenzene are easily generated at high temperatures, promoting the formation of highly toxic dioxins. This not only pollutes the air and water but also harms human health. Furthermore, the release of these chlorides can severely corrode equipment and pipelines, causing boiler fouling and slagging, thus affecting equipment lifespan. To address the aforementioned issues, if low-temperature treatment technology is used to pre-remove the chlorine contained in the substance, reducing the amount of chlorine involved in the dioxin synthesis reaction at the source, a series of adverse consequences caused by the generation of pollutants during subsequent high-temperature treatment can be effectively avoided.

[0003] High-chlorine solid wastes are diverse, varying in chlorine content and form, thus requiring different dechlorination devices. Currently, many researchers have developed various dechlorination devices and methods, such as thermal dechlorination (baking is a low-temperature pyrolysis method, an emerging technology for solid waste dechlorination with advantages of low energy consumption and high recovery rate). Some thermal dechlorination devices operate at high temperatures, leading to high energy consumption and complex processes, deviating from the principles of environmental protection and energy conservation. CN209584124 discloses a municipal solid waste pyrolysis carbon gasification treatment system, which uses pyrolysis at 730-750℃ followed by high-temperature dechlorination of the pyrolysis oil and gas; CN107022362B discloses a biomass or organic waste conversion equipment and process, requiring pre-dechlorination treatment of the waste at 400℃-600℃. Such pyrolysis devices require high energy consumption and cost, and still need improvement. There is also room for reducing the dechlorination temperature in dechlorination technology for plastic waste. For example, CN208151283U discloses a pyrolysis treatment system for chlorinated plastics, which removes 90% of the chlorine from plastics at 300℃-370℃; CN116064064A designs a method and system for pyrolysis recycling of waste plastics, which achieves a dechlorination efficiency of more than 90% for PVC and other plastic mixtures at a pyrolysis temperature of 200℃-430℃.

[0004] Besides temperature, the main problem with existing dechlorination devices lies in their limited scope; most devices only dechlorinate a specific type of waste, resulting in relatively low applicability. CN115960621A discloses an apparatus and method for low-temperature dechlorination of waste plastics coupled with catalytic pyrolysis to produce fuel oil, achieving 100% dechlorination efficiency within the range of 250℃-350℃. While this reduces energy consumption and increases dechlorination efficiency, the catalytic hydrogenation step is cumbersome and increases costs, and it can only dechlorinate a limited range of materials. CN115780475A discloses a method and system for microwave selective pyrolysis of mixed waste plastics for dechlorination and upgrading, dechlorinating chlorinated plastics within the range of 250℃-350℃. Similarly, its limitation lies in the fact that it can only dechlorinate plastics with a chlorine content of 3%-20%, and there is no suitable solid chlorination facility. CN112207115A discloses a process for co-processing medical waste using low-temperature thermal dechlorination and upgrading of hot flue gas coupled with a cement kiln. This process recycles hot flue gas at 220℃-280℃ to reduce energy consumption. However, some components in medical waste require higher temperatures for dechlorination, thus failing to achieve both low energy consumption and high dechlorination efficiency. For complex high-chlorine solid waste, there is an urgent need to find a more universal, efficient, energy-saving, and simplified pre-dechlorination technology. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method and apparatus for treating high-chlorine solid waste based on air pressure baking, which aims to solve the problems that existing desulfurization methods cannot guarantee high dechlorination efficiency while reducing energy consumption, and that they can only treat a single type of waste.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for treating high-chlorine solid waste based on pressure baking is provided. The method specifically involves: subjecting the high-chlorine solid waste to pressure baking at 250°C to 400°C, thereby converting the high-chlorine solid waste into baking coke, volatiles, and hydrogen chloride, and then absorbing the hydrogen chloride to achieve the treatment of the high-chlorine solid waste.

[0007] As a further preferred embodiment, the gas pressure baking is carried out in a flue gas atmosphere or a mixed atmosphere of inert gas and flue gas. Preferably, the flue gas is flue gas generated by the combustion of volatiles.

[0008] As a further preferred embodiment, when the high-chlorinated solid waste is plastic, biomass waste, or medical waste, the temperature of the pressure baking is 250℃~300℃; when the high-chlorinated solid waste is rubber waste, the temperature of the pressure baking is 300℃~400℃.

[0009] As a further preferred option, the working pressure of the air pressure baking is 1 bar to 50 bar.

[0010] As a further preferred embodiment, the roasting coke is gasified to obtain combustible gas, and a portion of the combustible gas is introduced into the pressure roasting apparatus to maintain the temperature and pressure of the pressure roasting.

[0011] According to another aspect of the present invention, a high-chlorine solid waste treatment device based on pressure baking is provided. This high-chlorine solid waste treatment device employs the aforementioned high-chlorine solid waste treatment method and specifically includes: a feeder, a pressure baking unit, and a chlorine solidifier, wherein:

[0012] The feeder is connected to the pneumatic baking unit and is used to supply high-chlorine solid waste to the pneumatic baking unit;

[0013] The pneumatic baking unit is used to pneumatically bake the high-chlorine solid waste at 250℃~400℃, so that it is converted into baking coke, volatiles and hydrogen chloride. The gas outlet of the pneumatic baking unit is connected to the solid chlorinator to send the mixed gas of volatiles and hydrogen chloride into the solid chlorinator. At the same time, the pneumatic baking unit is also provided with a solid outlet to discharge the baking coke.

[0014] The chlorine solidifier is used to absorb and fix hydrogen chloride in the mixed gas, thereby achieving the treatment of high-chlorine solid waste.

[0015] As a further preferred embodiment, the high-chlorine solid waste treatment device further includes a burner, the inlet of which is connected to the outlet of the solid chlorine unit, and the outlet of which is connected to the inlet of the pressure baking unit, for burning the volatiles, and then the generated flue gas is introduced into the pressure baking unit.

[0016] As a further preferred embodiment, the high-chlorine solid waste treatment device further includes a gasifier connected to the solid outlet of the pressure baking unit for gasifying the baked coke to obtain combustible gas.

[0017] As a further preferred embodiment, the high-chlorine solid waste treatment device further includes a gas separator. The inlet of the gas separator is connected to the outlet of the gasifier. The outlet of the gas separator is divided into two paths: one path is connected to the inlet of the pressure baking unit, and the other path is connected to the combustible gas collector, which is used to send a portion of the combustible gas into the pressure baking unit to maintain the temperature and pressure of the pressure baking unit.

[0018] As a further preferred embodiment, the gas pressure baking unit includes a dechlorination reactor and a support rod, a pressure sensor, and a temperature sensor disposed inside the dechlorination reactor. The dechlorination reactor is provided with a gas inlet for introducing inert gas; the support rod is used to drive the high-chlorine solid waste to rotate; and the pressure sensor and temperature sensor are used to measure the gas pressure and temperature of the dechlorination reactor.

[0019] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art:

[0020] 1. This invention utilizes air pressure baking to treat high-chlorine solid waste, achieving high-efficiency chlorine removal at lower temperatures. Compared with atmospheric pressure thermal dechlorination, it has higher dechlorination efficiency, thus reducing energy consumption while achieving high dechlorination efficiency. It is applicable to various types of high-chlorine solid waste. In addition, this method can also obtain clean and high-quality baking coke, thereby releasing chlorine as HCl at lower temperatures while deoxygenating and upgrading high-chlorine solid waste, reducing the difficulty of subsequent chlorine removal and enhancing reliability.

[0021] 2. In particular, the present invention performs gas pressure baking in a flue gas atmosphere, which can utilize the oxygen present in the flue gas to cause oxidation reaction in high-chlorine solid waste during thermal decomposition, accelerate the decomposition of chlorine-containing compounds in high-chlorine solid waste, enable organic chlorine to break carbon-chlorine bonds and carbon-hydrogen bonds at low temperature, inhibit the conversion of chlorine free radicals to organic chlorine such as CH3Cl, promote the release of chlorine in the form of HCl, and pass the flue gas generated by the combustion of volatiles into the gas pressure baking instrument, which can effectively utilize the heat generated by the combustion of volatiles to achieve a self-functional working mode, which is energy-saving and environmentally friendly.

[0022] 3. At the same time, the present invention sets reaction temperatures for different types of high-chlorine solid waste, and can achieve dechlorination effect according to the actual treatment needs of solid waste;

[0023] 4. In addition, by using gasification technology to convert low-chlorine-content baking coke into high-value-added combustible gas, the present invention can realize the resource utilization of solid waste, and by introducing part of the combustible gas into the pressure baking unit, the temperature and pressure of pressure baking can be maintained, thus realizing the recycling of heat. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the high-chlorine solid waste treatment device based on air pressure baking provided in an embodiment of the present invention.

[0025] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0026] 1-Feeder, 2-First condensation assembly, 3-Support rod, 4-Pressure sensor, 5-Temperature sensor, 6-Gas inlet, 7-Chronicizer, 8-Burner, 9-Booster pump, 10-Gasification furnace, 11-Gas separator, 12-Computer, 13-Temperature sensor, 14-Gas sensor, 15-Gas lock assembly, 16-Dechlorination reactor. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0028] According to one aspect of the present invention, a method for treating high-chlorine solid waste based on pressure baking is provided. Specifically, the method involves subjecting the high-chlorine solid waste to pressure baking at 250°C to 400°C and 1 bar to 50 bar, converting the high-chlorine solid waste into baking coke, volatiles, and hydrogen chloride. The hydrogen chloride is then absorbed to achieve the treatment of the high-chlorine solid waste. Baking refers to heat treatment under an inert atmosphere at a relatively low temperature range (generally 200°C to 300°C), while pressure baking refers to baking under gas pressure. This invention uses pressure baking to treat high-chlorine solid waste, which can effectively reduce the treatment temperature, reduce energy consumption, and achieve high dechlorination efficiency, making it suitable for various types of high-chlorine solid waste. For biomass-based high-chlorine solid waste, the reaction of oxygen-containing functional groups with chlorine generates HCl / CH3Cl, which is released into the gas phase, achieving dechlorination. Pressure baking accelerates the decomposition of hemicellulose, lignin, and cellulose, releasing more carboxyl and methoxy groups, and promotes secondary reactions between volatile substances and primary decomposition intermediates (active cellulose, L-glucan, and xylan, etc.), further removing oxygen-containing functional groups and ensuring sufficient contact with chlorine, thus improving dechlorination efficiency. For high-chlorine solid waste from rubber and PVC (plastics, medical waste), pressure baking promotes the breakage of carbon-chlorine and carbon-hydrogen bonds in organochlorine compounds at low temperatures, completing the dehydrogenation, dechlorination, and HCl production pathway, promoting the pyrolysis of chlorine-containing compounds into the gas, and improving dechlorination efficiency.

[0029] Furthermore, pressure baking is performed in a flue gas atmosphere or a mixed atmosphere of inert gas and flue gas. The oxygen present in the flue gas causes oxidation of the high-chlorine solid waste during thermal pyrolysis, accelerating the decomposition of chlorine-containing compounds and inhibiting the conversion of chlorine free radicals to organochlorines such as CH3Cl, while promoting the release of chlorine as HCl. This flue gas can be generated from the combustion of volatiles, thus utilizing the heat generated to heat the pressure baking unit, achieving a self-powered operating mode with energy-saving and environmentally friendly advantages.

[0030] Furthermore, the roasted coke is gasified to obtain combustible gas. If the heat generated by the combustion of volatiles is insufficient, some of the combustible gas can be introduced into the gas pressure roasting instrument to maintain the temperature and pressure of the gas pressure roasting and realize the recycling of heat.

[0031] like Figure 1As shown, according to another aspect of the present invention, a high-chlorine solid waste treatment device based on pressure baking is provided. This high-chlorine solid waste treatment device employs the aforementioned high-chlorine solid waste treatment method and specifically includes: a feeder 1, a pressure baking unit, a chlorine solidifier 7, and a control unit 12, wherein:

[0032] The feeder 1 is connected to the pneumatic baking unit via the first locking assembly 2 and is used to supply high-chlorine solid waste to the pneumatic baking unit.

[0033] The pneumatic baking unit is used to pneumatically bake high-chlorine solid waste at 250℃~400℃, so that it is converted into baking coke, volatiles and hydrogen chloride. The gas outlet of the pneumatic baking unit is connected to the solid chlorinator 7 to send the mixed gas of volatiles and hydrogen chloride into the solid chlorinator 7. At the same time, the pneumatic baking unit is also provided with a solid outlet to discharge the baking coke by gravity.

[0034] The chlorine solidifier 7 is used to absorb and fix hydrogen chloride in the mixed gas, thereby achieving the treatment of high-chlorine solid waste. The chlorine solidifier 7 adopts a structure with a lower layer of leaching water and an upper layer of adsorption layer. The adsorption layer uses calcium-based adsorbent or magnesium-based adsorbent.

[0035] The control unit 12 is used to record parameters during the operation of the high-chlorine solid waste treatment device in order to achieve automated control.

[0036] Furthermore, the high-chlorine solid waste treatment device also includes a burner 8. The inlet of the burner 8 is connected to the outlet of the chlorinator 7, and its outlet is connected to the inlet of the pressure baking unit via a booster pump 9. This booster pump is used to burn the volatiles, and then the resulting high-temperature flue gas is pressurized into high-temperature, high-pressure flue gas and fed into the pressure baking unit. The oxygen present in the flue gas causes the high-chlorine solid waste to undergo an oxidation reaction during thermal pyrolysis, accelerating the decomposition of chlorine-containing compounds in the high-chlorine solid waste. This allows organic chlorines to break carbon-chlorine and carbon-hydrogen bonds at low temperatures, inhibits the conversion of chlorine free radicals to organic chlorines such as CH3Cl, and promotes the release of chlorine in the form of HCl. At the same time, the high-temperature flue gas generated by the combustion of volatiles is reintroduced into the pressure baking unit, which can also directly heat the pressure baking unit, thus achieving self-heating.

[0037] Furthermore, the high-chlorine solid waste treatment device also includes a gasifier 10 and a gas separator 11. The gasifier 10 is connected to the solid outlet of the pressure baking unit through a second locking component 5, and is used to gasify the baked coke under limited oxygen conditions to obtain high-value combustible gas, thereby achieving clean, energy-saving and high-value resource utilization of high-chlorine solid waste. The inlet of the gas separator 11 is connected to the outlet of the gasifier 10. The outlet of the gas separator 11 is divided into two paths, one of which is connected to the inlet of the pressure baking unit and the other of which is connected to the combustible gas collector. When the heat generated by the combustion of volatiles is insufficient, some combustible gas can be sent into the pressure baking unit to maintain the temperature and pressure of the pressure baking unit, making the high-chlorine solid waste treatment device more flexible.

[0038] Furthermore, the gas pressure baking unit includes a dechlorination reactor 16 and a support rod 3, a pressure sensor 4, a temperature sensor 13, and a gas concentration sensor 14 disposed inside the dechlorination reactor 16. The dechlorination reactor 16 is provided with a gas inlet 6 for introducing inert gas, and the gas inlet 6 is controlled by a gas lock assembly 15 to adjust the inert gas introduction rate. The support rod 3 is used to drive the high-chlorine solid waste to rotate. The pressure sensor 4, temperature sensor 13, and gas concentration sensor 14 are used to measure the gas pressure, temperature, and gas concentration of the dechlorination reactor 16, respectively, wherein the gas concentration is preferably HCl concentration.

[0039] The high-chlorine solid waste treatment device based on pressure baking provided by this invention improves dechlorination efficiency while directly utilizing the purified volatile matter for combustion heating, achieving self-heating without the need for additional energy, thus realizing high efficiency and energy saving. Furthermore, the baking coke is converted into high-value-added combustible gas, turning waste into treasure while treating high-chlorine solid waste, and has high industrial application value.

[0040] The technical solution provided by the present invention will be further described below with reference to specific embodiments.

[0041] Example 1

[0042] S1 crushes the plastic waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment, reaching an initial pressure of 0 bar.

[0043] The S2 dechlorination reactor is heated to 250°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 20 bar, so that plastic waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0044] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0045] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a calcium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the dechlorination efficiency of plastic waste was measured to reach 72%.

[0046] Example 2

[0047] S1 crushes the plastic waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment, reaching an initial pressure of 0 bar.

[0048] The S2 dechlorination reactor is heated to 250°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 15 bar, so that plastic waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0049] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0050] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a calcium-based adsorbent. The final measured dechlorination efficiency of plastic waste reaches 69%.

[0051] Example 3

[0052] S1 crushes the plastic waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment, reaching an initial pressure of 0 bar.

[0053] The S2 dechlorination reactor is heated to 275°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 20 bar, so that plastic waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0054] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0055] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a calcium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the dechlorination efficiency of plastic waste was measured to reach 81%.

[0056] Example 4

[0057] S1 crushes the plastic waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment, reaching an initial pressure of 0 bar.

[0058] The S2 dechlorination reactor is heated to 300°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 22 bar, so that plastic waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0059] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0060] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a calcium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the dechlorination efficiency of plastic waste is measured to reach 97%.

[0061] Example 5

[0062] S1 crushes the biomass waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment and an initial pressure of 0 bar.

[0063] The S2 dechlorination reactor is heated to 250°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 20 bar, so that biomass waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0064] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0065] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a magnesium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas. The flue gas is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the biomass waste was measured to have a dechlorination efficiency of 46%.

[0066] Example 6

[0067] S1 crushes the medical waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge the waste to achieve an oxygen-free environment and reach an initial pressure of 20 bar.

[0068] The S2 dechlorination reactor is heated to 250°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 50 bar, so that medical waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0069] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0070] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a magnesium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the medical waste was measured to have a dechlorination efficiency of 76%.

[0071] Example 7

[0072] S1 crushes the rubber waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment, reaching an initial pressure of 10 bar.

[0073] The S2 dechlorination reactor is heated to 300°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 20 bar, so that the rubber waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0074] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0075] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a magnesium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the rubber waste was measured to have a dechlorination efficiency of 45%.

[0076] Example 8

[0077] S1 crushes the rubber waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment, reaching an initial pressure of 10 bar.

[0078] The S2 dechlorination reactor is heated to 350°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 26 bar, so that the rubber waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0079] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0080] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a magnesium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the rubber waste was measured to have a dechlorination efficiency of 72%.

[0081] Example 9

[0082] S1 crushes the rubber waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment, reaching an initial pressure of 10 bar.

[0083] The S2 dechlorination reactor is heated to 400°C at a heating rate of 5°C / min and held at this temperature for 60 min to reach a final pressure of 30 bar, so that the rubber waste is baked under pressure to generate baking coke, hydrogen chloride and volatiles.

[0084] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0085] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a magnesium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then converted into high-temperature and high-pressure flue gas by the booster pump 9 and sent to the dechlorination reactor 16 for heating and pressurization. Finally, the dechlorination efficiency of rubber waste is measured to be 98%.

[0086] Comparative Example 1

[0087] S1 crushes the plastic waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge the reactor and achieve an oxygen-free environment, and the dechlorination reactor 16 is kept at normal pressure.

[0088] The S2 dechlorination reactor is heated to 250°C at a heating rate of 5°C / min and held at this temperature for 60 min, so that plastic waste generates pyrolytic coke, hydrogen chloride and volatiles under pyrolysis conditions.

[0089] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0090] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a calcium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then sent to the dechlorination reactor 16 for heating. The final measured dechlorination efficiency of plastic waste reaches 40%.

[0091] Comparative Example 2

[0092] S1 crushes the biomass waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment. The dechlorination reactor 16 is kept at normal pressure.

[0093] The S2 dechlorination reactor is heated to 250°C at a heating rate of 5°C / min and held at this temperature for 60 min, so that biomass waste is converted into pyrolytic coke, hydrogen chloride and volatiles under pyrolysis conditions.

[0094] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0095] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a calcium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then sent to the dechlorination reactor 16 for heating. The final measured dechlorination efficiency of biomass waste reaches 25%.

[0096] Comparative Example 3

[0097] S1 crushes the rubber waste and feeds it into the dechlorination reactor 16 through the feeder 1. Inert gas is introduced through the gas inlet 6 to purge and achieve an oxygen-free environment. The dechlorination reactor 16 is kept at normal pressure.

[0098] The S2 dechlorination reactor is heated to 300°C at a heating rate of 5°C / min and held at this temperature for 60 min, so that the rubber waste generates pyrolytic coke, hydrogen chloride and volatiles under pyrolysis conditions.

[0099] S3 roasted coke enters gasifier 10 under gravity and is converted into combustible gas under limited oxygen conditions. Part of the combustible gas is sent to dechlorination reactor 16 for heating.

[0100] The mixture of S4 volatiles and hydrogen chloride enters the solid chlorinator 7, where the hydrogen chloride gas is thoroughly purified by a calcium-based adsorbent. The volatiles enter the burner 8 and are burned to generate high-temperature flue gas, which is then sent to the dechlorination reactor 16 for heating. The final measured dechlorination efficiency of rubber waste reaches 35%.

[0101] By comparing Example 1 with Comparative Example 1, Example 5 with Comparative Example 2, and Example 7 with Comparative Example 3, it can be found that gas pressure baking can effectively improve dechlorination efficiency compared with pyrolysis under normal pressure.

[0102] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements 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 method for treating high-chlorine solid waste based on pressure baking, characterized in that, The method specifically involves: High-chlorinated solid waste, such as rubber, plastics, and medical waste, is subjected to pressure baking at 250℃ to 400℃ in a flue gas atmosphere or a mixed atmosphere of inert gas and flue gas. Pressure baking promotes the breakage of carbon-chlorine and carbon-hydrogen bonds in organochlorine compounds at low temperatures, completing the dehydrogenation, dechlorination, and HCl production pathway. This promotes the decomposition of chlorine-containing compounds into gas, converting the high-chlorinated solid waste into baking coke, volatiles, and hydrogen chloride. The hydrogen chloride is then absorbed to treat the high-chlorinated solid waste. When the high-chlorinated solid waste is plastic or medical waste, the pressure baking temperature is 250℃ to 300℃; when the high-chlorinated solid waste is rubber waste, the pressure baking temperature is 300℃ to 400℃, and the working pressure of the pressure baking is 1 bar to 50 bar.

2. The method for treating high-chlorine solid waste based on pressure baking as described in claim 1, characterized in that, The flue gas is produced by the combustion of volatile components.

3. The method for treating high-chlorine solid waste based on pressure baking as described in claim 1 or 2, characterized in that, The roasted coke is gasified to obtain combustible gas, and a portion of the combustible gas is introduced into the gas pressure baking apparatus to maintain the temperature and pressure of the gas pressure baking.

4. A high-chlorine solid waste treatment device based on pressure baking, characterized in that, The high-chlorine solid waste treatment device adopts the high-chlorine solid waste treatment method as described in any one of claims 1 to 3, specifically including: a feeder (1), a pneumatic baking unit, and a chlorine solidifier (7), wherein: The feeder (1) is connected to the pneumatic baking unit and is used to provide high-chlorine solid waste to the pneumatic baking unit. The high-chlorine solid waste is rubber, plastic, and medical waste. The pneumatic baking unit is used to perform pneumatic baking on the high-chlorine solid waste at 250℃~400℃ in a flue gas atmosphere or a mixed atmosphere of inert gas and flue gas, so that it is converted into baking coke, volatiles and hydrogen chloride. The gas outlet of the pneumatic baking unit is connected to the solid chlorinator (7) to send the mixed gas of volatiles and hydrogen chloride into the solid chlorinator (7). At the same time, the pneumatic baking unit is also provided with a solid outlet to discharge the baking coke. When the high-chlorine solid waste is plastic and medical waste, the temperature of pneumatic baking is 250℃~300℃; when the high-chlorine solid waste is rubber waste, the temperature of pneumatic baking is 300℃~400℃, and the working pressure of pneumatic baking is 1 bar~50 bar. The chlorine solidifier (7) is used to absorb and fix hydrogen chloride in the mixed gas, thereby achieving the treatment of high-chlorine solid waste.

5. The high-chlorine solid waste treatment device based on pressure baking as described in claim 4, characterized in that, The high-chlorine solid waste treatment device also includes a burner (8), the inlet of which is connected to the outlet of the solid chlorine generator (7), and its outlet is connected to the inlet of the pressure baking unit for burning the volatiles, and then the generated flue gas is introduced into the pressure baking unit.

6. The high-chlorine solid waste treatment device based on pressure baking as described in claim 4, characterized in that, The high-chlorine solid waste treatment device also includes a gasifier (10), which is connected to the solid outlet of the pressure baking unit and is used to gasify the baking coke to obtain combustible gas.

7. The high-chlorine solid waste treatment device based on pressure baking as described in claim 4, characterized in that, The high-chlorine solid waste treatment device also includes a gas separator (11). The inlet of the gas separator (11) is connected to the outlet of the gasifier (10). The outlet of the gas separator (11) is divided into two paths: one path is connected to the inlet of the pressure baking unit, and the other path is connected to the combustible gas collector, which is used to send part of the combustible gas into the pressure baking unit to maintain the temperature and pressure of the pressure baking unit.

8. The high-chlorine solid waste treatment device based on pressure baking as described in any one of claims 4 to 7, characterized in that, The gas pressure baking unit includes a dechlorination reactor (16) and a support rod (3), a pressure sensor (4) and a temperature sensor (14) disposed inside the dechlorination reactor (16). The dechlorination reactor (16) is provided with a gas inlet (6) for introducing inert gas. The support rod (3) is used to drive the high-chlorine solid waste to rotate. The pressure sensor (4) and the temperature sensor (14) are used to measure the gas pressure and temperature of the dechlorination reactor (16).

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