Waste plastic catalytic cracking and oiling system

Abstract

The invention relates to the technical field of waste plastic utilization, in particular to a waste plastic catalytic cracking and oiling system. Comprising a pulverizator, a conveying belt is fixed to a discharging port of the pulverizator, a spiral feeder is arranged at one end of the bottom of the conveying belt, a feeding port is formed in the top of the end, close to the conveying belt, of the spiral feeder, the spiral feeder is rotationally connected to the inner side of the feeding port, and an outlet in the bottom of one end of the spiral feeder is connected with a first rotary kiln through a first pipeline; rotating blades are rotationally connected into the first rotary kiln, a control motor is fixed to one end of the first rotary kiln, the output end of the control motor is connected with the rotating blades, and an output port in one end of the first rotary kiln is connected with a first cyclone separator. According to the waste plastic catalytic cracking and oiling system provided by the invention, a heating mode of coupling internal particle direct heating and external flue gas indirect heating is adopted, so that the plastic heating uniformity can be effectively improved, the coking risk can be reduced, and meanwhile, the fuel oil yield can be improved by virtue of a relatively high heating rate.

Description

Technical Field

[0001] The invention relates to the technical field of waste plastic utilization, and in particular to a waste plastic catalytic cracking oil conversion system. Background Art

[0002] Plastics are widely used in all walks of life in the national economy due to their advantages of light weight, corrosion resistance, easy processing, low cost and strong chemical stability. They play an extremely important role in many fields such as packaging materials, medical equipment, electronic devices, and construction. According to statistics, in 2022, the total output of plastic products in my country will be 69.01 million tons. According to statistics, in 2022, my country will produce 63 million tons of waste plastics, of which only 18.9 million tons will be recycled, accounting for 30%, while the landfill volume will be 20.16 million tons and the incineration volume will be 19.53 million tons, accounting for 32% and 31% respectively, and the direct abandonment will account for 7%. The mechanical recycling method is to convert plastics into secondary materials by mechanical force after washing and processing, and has high requirements for the type of plastics. How to deal with plastic waste in a green way has become a top priority. Compared with traditional plastic recycling methods, the chemical recycling method of plastics is one of the most promising waste plastic utilization technologies, which can realize resource and energy utilization.

[0003] Traditional methods of treating waste plastics include incineration, landfill, physical recycling and modification and regeneration. Pyrolysis, as an emerging clean technology, converts waste plastics into small molecular components such as fuel oil, high calorific value gas and pyrolytic carbon by heating them in an inert atmosphere. With the continuous advancement of treatment technology, converting waste plastics into high-value fuel oil through pyrolysis is an efficient recycling method. In recent years, catalytic cracking has attracted widespread attention.

[0004] In the patent with the publication number CN105713641A, a device and method for preparing pyrolysis oil by pyrolysis and catalytic debromination of brominated flame retardant waste plastics is disclosed, which combines the fluidized pyrolysis reaction with the catalytic debromination reaction, fully utilizes the excellent heat and mass transfer characteristics of the fluidized bed, and realizes the high-yield preparation of pyrolysis oil of flame retardant waste plastics. Although direct heating of the internal particles can effectively increase the heating rate by using a fluidized bed reactor, the high-viscosity plastic melt generated by the heat is easy to wrap the bed material particles, thereby causing defluidization, resulting in equipment blockage, and affecting the normal operation and maintenance of the equipment.

[0005] In the patent with the publication number CN105713641A, a continuous tubular pyrolysis furnace for the ultimate disposal of waste plastics is provided. The waste plastics in the pyrolysis furnace are heated and cracked under the action of a catalyst to generate gaseous "oil and gas" and solid carbon. Since the pyrolysis furnace adopts a tubular furnace transportation design, it is suitable for the continuity and low energy consumption of industrial production, that is, the ultimate disposal of low-value waste plastics is achieved. However, the conventional externally heated tubular furnace or rotary kiln has poor thermal conductivity of plastics, low heating rate, long reaction time, and low liquid yield.

[0006] In the patent with the publication number CN110591750A, a process and device for cracking chlorine-containing plastics to produce oil is provided, which has a strong gas-solid mixing intensity in the dechlorination fluidized bed, thereby effectively improving the dechlorination efficiency of chlorine-containing plastics; the carbon deposit cracking catalyst produced in the catalytic cracking fluidized bed is sent to the roasting fluidized bed, and the carbon accumulated on its surface is fully burned, so that the carbon deposit cracking catalyst has the catalytic function again, and the regeneration is completed. The regenerated cracking catalyst is sent to the catalytic cracking fluidized bed again to achieve the regeneration and recycling of the catalyst. However, the catalyst particles are treated by roasting or gasification roasting, and the temperature of the particles after treatment is uniform. When they are sent back to the reactor again, the catalyst particles with higher temperatures are easy to be rapidly carbonized and deactivated on their surfaces when they come into contact with the low-temperature plastics. At the same time, the catalyst particles with smaller sizes have poor fluidity and are easy to be bonded and agglomerated under the action of molten plastics.

[0007] In the above-mentioned prior art for processing waste plastics, the complete decomposition of plastics cannot be guaranteed when they are used, and the efficiency of resource utilization of waste plastics is not high, which cannot better protect the environment.

[0008] To this end, a waste plastic catalytic cracking oil system is designed to provide another technical solution to the above technical problems. Summary of the invention

[0009] Based on this, it is necessary to provide a waste plastic catalytic cracking oil system to solve the technical problems raised in the above background technology.

[0010] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0011] A waste plastic catalytic cracking oil system comprises a pulverizer, wherein a conveyor belt is fixed to the discharge port of the pulverizer, a screw feeder is arranged at one end of the bottom of the conveyor belt, a feed port is opened at the top of the screw feeder near one end of the conveyor belt, the inner side of the feed port is rotatably connected to the screw feeder, the outlet at the bottom of one end of the screw feeder is connected to a first rotary kiln through a first pipeline, the interior of the first rotary kiln is rotatably connected to a rotary blade, a control motor is fixed to one end of the first rotary kiln, the output end of the control motor is connected to the rotary blade, the output port at one end of the first rotary kiln is connected to a first cyclone separator, the bottom of the first rotary kiln is connected to a second rotary kiln through a second pipeline, the output end of the second rotary kiln is connected to a second cyclone separator, the output end of the second cyclone separator is connected to a third rotary kiln through a third pipeline, the output end of the third rotary kiln is connected to a third cyclone separator, a microwave heating device is fixed to the outer side of the third cyclone separator, the output end of the third cyclone separator is connected to a bucket elevator, and the output end of the top of the bucket elevator is connected to a composite combustion chamber.

[0012] As a preferred embodiment of the waste plastic catalytic cracking oil conversion system provided by the present invention, a plurality of ceramic balls with different particle sizes are placed inside the composite combustion chamber.

[0013] As a preferred embodiment of the waste plastic catalytic cracking oil system provided by the present invention, the diameter of the rotating blade increases gradually from the end far away from the control motor to the end close to the control motor, and the minimum gap between the rotating blade and the inner wall of the first rotary kiln is 5 cm.

[0014] As a preferred embodiment of the waste plastic catalytic cracking oil system provided by the present invention, a first control valve is provided at the bottom of the first cyclone separator, and a second control valve is provided at the bottom of the second cyclone separator.

[0015] As a preferred embodiment of the waste plastic catalytic cracking oil system provided by the present invention, the tops of the first cyclone separator, the second cyclone separator and the third cyclone separator are all connected to a gas mixing chamber.

[0016] As a preferred embodiment of the waste plastic catalytic cracking oil system provided by the present invention, the output end of the gas mixing chamber is connected to the first cooling tower, a first circulating oil pump is fixed at one end of the first cooling tower, the input end of the first circulating oil pump is connected to the bottom end of the first cooling tower, the output end of the first circulating oil pump is connected to the spray head inside the first cooling tower, the output end of the first circulating oil pump is also connected to the second rotary kiln, the top of the first cooling tower is connected to the second cooling tower through a pipeline, a second circulating oil pump is fixed at one end of the second cooling tower, the top of the second cooling tower is connected to the third cooling tower through a pipeline, a third circulating oil pump is fixed at one end of the third cooling tower, the top of the third cooling tower is connected to the convergent-divergent nozzle through a pipeline, and the convergent-divergent nozzle is connected to the composite combustion chamber.

[0017] As a preferred embodiment of the waste plastic catalytic cracking oil system provided by the present invention, it also includes a blower, the output end of the blower is connected to a heat exchanger, the output end of the heat exchanger enters the interior of the third cooling tower, the second cooling tower and the first cooling tower in sequence, and is connected to the convergent and divergent nozzle.

[0018] As a preferred embodiment of the waste plastic catalytic cracking oil system provided by the present invention, a low-temperature particle pipe, a medium-temperature particle pipe and a high-temperature particle pipe are sequentially opened at the bottom of the composite combustion chamber from one end to the other end, the bottom of the low-temperature particle pipe is connected to the first pipe, the bottom of the medium-temperature particle pipe is connected to the second pipe, and the bottom of the high-temperature particle pipe is connected to the third pipe.

[0019] As a preferred embodiment of the waste plastic catalytic cracking oil system provided by the present invention, a smoke outlet is provided at the top of one end of the first rotary kiln, the first cyclone separator, the second rotary kiln, the second cyclone separator and the third rotary kiln, a smoke inlet is provided at the bottom of one end of the first rotary kiln, the first cyclone separator, the second rotary kiln, the second cyclone separator and the third rotary kiln, a smoke exhaust port is provided at one end of the composite combustion chamber close to the bucket elevator, the smoke exhaust port is connected to the smoke inlet on the third rotary kiln, the smoke outlet on the first rotary kiln is connected to the heat exchanger, the bottom of the heat exchanger is connected to an induced draft fan, and the output end of the induced draft fan is connected to a flue gas processor.

[0020] It can be seen without a doubt that the above-mentioned technical solution of the present application can definitely solve the technical problem to be solved by the present application.

[0021] At the same time, through the above technical solutions, the present invention has at least the following beneficial effects:

[0022] 1. The waste plastic catalytic cracking oil system provided by the present invention can effectively improve the heating uniformity of plastics and reduce the risk of coking by adopting a heating mode that couples internal particle direct heating with external flue gas indirect heating. At the same time, the higher heating rate can increase the fuel oil yield.

[0023] 2. The present invention is based on a rotary kiln pyrolysis device coupled with internal and external heating, and adopts a method that integrates pyrolysis and separation to convert waste plastics into light components of diesel and gasoline; the rapid start and stop and rapid heating characteristics of microwave heating are utilized to ensure the complete cracking of plastics; the composite combustion chamber can realize the cascade utilization of catalyst particles, achieve full pyrolysis of plastics, and prevent rapid carbon deposition, deactivation and adhesion on the catalyst surface; ultimately, the selectivity and yield of pyrolysis oil products are improved, and waste plastics are utilized as resources, while protecting the environment and maximizing the economy of pyrolysis oil.

[0024] 3. The present invention adopts a microwave heating device, which can achieve the purpose of rapid start and stop and rapid heating according to the residual volatile matter in the carbon slag after the rotary kiln reaction, thereby ensuring the complete cracking of the plastic.

[0025] 4. The present invention adopts a cascade utilization mode of catalyst particles of different sizes and temperatures, and sends the low-temperature large-particle catalyst into the first rotary kiln, which can effectively prevent its surface from rapid carbonization and deactivation and ensure its fluidity. At the same time, the adhesion between particles is reduced through the action of internal rotating blades; the medium-temperature medium-particle catalyst and the high-temperature small-particle catalyst are respectively sent to the second rotary kiln and the third rotary kiln to ensure that the plastic can be fully cracked. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0028] Figure 2 It is a schematic diagram of the rotating blade structure of the present invention.

[0029] In the figure: 1. pulverizer; 2. conveyor belt; 3. feed port; 4. screw feeder; 5. first rotary kiln; 6. rotating blades; 7. control motor; 8. first cyclone separator; 9. first control valve; 10. second rotary kiln; 11. second cyclone separator; 12. second control valve; 13. third rotary kiln; 14. third cyclone separator; 15. microwave heating device; 16. bucket elevator; 17. gas mixing chamber; 18. compound combustion chamber; 19. convergent-divergent nozzle; 20. first cooling tower; 21. first circulating oil pump; 22. second cooling tower; 23. second circulating oil pump; 24. third cooling tower; 25. third circulating oil pump; 26. blower; 27. heat exchanger; 28. induced draft fan; 29. ​​flue gas processor. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0031] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0032] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0033] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0034] Reference Figure 1-Figure 2 A waste plastic catalytic cracking oilification system comprises a pulverizer 1, a conveyor belt 2 is fixed to the discharge port of the pulverizer 1, so that the waste plastic can be pulverized by the pulverizer 1 and transported by the conveyor belt 2, a screw feeder 4 is arranged at one end of the bottom of the conveyor belt 2, a feed port 3 is opened at the top of the screw feeder 4 near one end of the conveyor belt 2, so that the conveyor belt 2 can guide the pulverized material of the pulverizer 1 into the inside of the feed port 3, the inner side of the feed port 3 is rotatably connected with the screw feeder 4, so that the screw feeder 4 is driven to rotate by an external motor, so that the screw feeder 4 can transport the pulverized material entering through the feed port 3 to the outlet, and the outlet at the bottom of one end of the screw feeder 4 is connected to the first rotary kiln 5 through the first pipeline, so that the screw feeder 4 can send the pulverized material inside the feed port 3 into the inside of the first rotary kiln 5 through the first pipeline for preliminary pyrolysis;

[0035] The first rotary kiln 5 is internally connected with a rotary blade 6, the diameter of the rotary blade 6 increases from left to right, and the minimum gap between the rotary blade 6 and the inner wall of the first rotary kiln 5 is 5 cm. A control motor 7 is fixed to one end of the first rotary kiln 5, and the output end of the control motor 7 is connected to the rotary blade 6, so that the operation of the control motor 7 can drive the rotary blade 6 to rotate, thereby achieving the purpose of separating the agglomerated large particles. The output port at one end of the first rotary kiln 5 is connected to a first cyclone separator 8, so that the remaining mixture of the reaction can be separated through the first cyclone separator 8. The bottom of the first rotary kiln 5 is connected to the second rotary kiln 10 through a second pipeline. The bottom of the first cyclone separator 8 is provided with a first control valve 9, so that the catalyst, oil-gas mixture, carbon slag, ash and unreacted remaining materials are controlled by the first control valve 9 to fall into the second rotary kiln 10 for secondary pyrolysis;

[0036] The output end of the second rotary kiln 10 is connected to a second cyclone separator 11, so that the mixture remaining after the reaction inside the second rotary kiln 10 can be separated through the second cyclone separator 11. The output end of the second cyclone separator 11 is connected to a third rotary kiln 13 through a third pipeline. A second control valve 12 is provided at the bottom of the second cyclone separator 11, and the second control valve 12 can control the carbon deposited catalyst particles, carbon residue, ash residue and the remaining materials that have not reacted completely to continue to fall into the third rotary kiln 13 for three pyrolysis. The output end of the third rotary kiln 13 is connected to a third cyclone separator 14, so that the mixture remaining after the reaction inside the third rotary kiln 13 can be separated through the third pipeline. The third cyclone separator 14 is used for separation. A microwave heating device 15 is fixed on the outside of the third cyclone separator 14, so that the microwave heating device 15 has the characteristics of rapid start and stop and rapid heating. During the process, the carbon slag coming out of the third rotary kiln 13 is sampled and tested. If there are volatiles, that is, the substance has not reacted completely, it is turned on. If there are no volatiles, that is, the reaction is complete, it is closed, and the carbon slag can be used as a wave absorber; the output end of the third cyclone separator 14 is connected to a bucket elevator 16, and the output end at the top of the bucket elevator 16 is connected to a composite combustion chamber 18, so that the carbon deposited catalyst particles, carbon slag, and ash slag can be lifted and transported into the interior of the composite combustion chamber 18 through the bucket elevator 16;

[0037] Preferably, a plurality of ceramic balls loaded with catalyst active components of different particle sizes are placed inside the composite combustion chamber 18, and the particle sizes are 3 cm, 1 cm and 0.5 cm respectively, so that the ceramic balls can be heated by burning natural gas inside the composite combustion chamber 18 and generate hot flue gas, and then the ceramic balls enter the first rotary kiln 5, the second rotary kiln 10 and the third rotary kiln 13 in order from large to small in particle size, and the plastic is also allowed to enter the first rotary kiln at the same time, and then after the working condition stabilizes, the natural gas is cut off, and the heat at this time comes from the combustion heat released by the pyrolysis of the plastic to produce cracking gas.

[0038] The tops of the first cyclone separator 8, the second cyclone separator 11 and the third cyclone separator 14 are all connected to a gas mixing chamber 17, so that the high-temperature gases separated by the first cyclone separator 8, the second cyclone separator 11 and the third cyclone separator 14 can be concentrated inside the gas mixing chamber 17, and the output end of the gas mixing chamber 17 is connected to a first cooling tower 20, and a first circulating oil pump 21 is fixed at one end of the first cooling tower 20, and the input end of the first circulating oil pump 21 is connected to the bottom end of the first cooling tower 20, and the output end of the first circulating oil pump 21 is connected to the inside of the first cooling tower 20. The output end of the first circulating oil pump 21 is also connected to the second rotary kiln 10, so that the high-temperature gas in the gas mixing chamber 17 can enter the interior of the first cooling tower 20, and spray through the operation of the first circulating oil pump 21, so that the heavy tar with a condensation temperature between 350-450° C. in the oil-gas mixture is condensed. At the same time, the condensed heavy tar is sprayed into the interior of the second rotary kiln 10 in the form of droplets under the operation of the first circulating oil pump 21, and the heavy components in the pyrolysis products can be pyrolyzed again, so that they are further cracked into light components;

[0039] The top of the first cooling tower 20 is connected to the second cooling tower 22 through a pipeline, so that the uncondensed light component gas inside the first cooling tower 20 can continue to enter the second cooling tower 22. A second circulating oil pump 23 is fixed at one end of the second cooling tower 22. The input end of the second circulating oil pump 23 is connected to the bottom end of the second cooling tower 22, and the output end of the second circulating oil pump 23 is connected to the spray head inside the second cooling tower 22. After the second circulating oil pump 23 is sprayed, the diesel with a condensation temperature between 180-350°C in the oil-gas mixture is condensed.

[0040] The top of the second cooling tower 22 is connected to the third cooling tower 24 through a pipeline, so that the uncondensed light component gas inside the second cooling tower 22 continues to enter the third cooling tower 24. A third circulating oil pump 25 is fixed to one end of the third cooling tower 24. The input end of the third circulating oil pump 25 is connected to the bottom end of the third cooling tower 24, and the output end of the third circulating oil pump 25 is connected to the spray head inside the third cooling tower 24. After the third circulating oil pump 25 sprays, the gasoline in the oil-gas mixture with a condensation temperature below 180°C condenses. The top of the third cooling tower 24 is connected to a convergent-divergent nozzle 19 through a pipeline. The convergent-divergent nozzle 19 is connected to the compound combustion chamber 18, so that the uncondensed hydrogen, methane and other combustible gases inside the third cooling tower 24 finally enter the contraction position of the convergent-divergent nozzle 19;

[0041] It also includes a blower 26, the output end of which is connected to a heat exchanger 27, so that the blower 26 preliminarily preheats the air required for combustion through the heat exchanger 27, and the output end of the heat exchanger 27 sequentially enters the third cooling tower 24, the second cooling tower 22 and the first cooling tower 20, and then is connected to the convergent-divergent nozzle 19, so that the preheated air can be preheated again through the third cooling tower 24, the second cooling tower 22 and the first cooling tower 20 in sequence, and finally sent to the interior of the composite combustion chamber 18 through the convergent-divergent nozzle 19, so that the carbon-deposited catalyst particles, carbon slag and ash slag discharged through the output end of the bucket elevator 16 enter the interior of the composite combustion chamber 18, and the carbon-deposited catalyst particles and carbon slag are burned inside the composite combustion chamber 18;

[0042] The bottom of the composite combustion chamber 18 is provided with a low-temperature particle pipe, a medium-temperature particle pipe and a high-temperature particle pipe in sequence from one end to the other, so that the low-temperature large particles (3 cm), medium-temperature medium particles (1 cm) and high-temperature small particles (0.5 cm) catalysts remaining after combustion can enter the low-temperature particle pipe, medium-temperature particle pipe and high-temperature particle pipe from near to far respectively under the action of gas purge. The bottom of the low-temperature particle pipe is connected to the first pipe, so that the low-temperature large particles can enter the first rotary kiln 5. The bottom of the medium-temperature particle pipe is connected to the second pipe, so that the medium-temperature medium particles can enter the second rotary kiln 10. The bottom of the high-temperature particle pipe is connected to the third pipe, so that the high-temperature small particles can enter the third rotary kiln 13.

[0043] The first rotary kiln 5, the first cyclone separator 8, the second rotary kiln 10, the second cyclone separator 11 and the third rotary kiln 13 are all provided with smoke outlets at the top of one end, and the first rotary kiln 5, the first cyclone separator 8, the second rotary kiln 10, the second cyclone separator 11 and the third rotary kiln 13 are all provided with smoke inlets at the bottom of one end, so that the smoke inlet of the first rotary kiln 5 is connected with the smoke outlet of the first cyclone separator 8, the smoke inlet of the first cyclone separator 8 is connected with the smoke outlet of the second rotary kiln 10, the smoke inlet of the second rotary kiln 10 is connected with the smoke outlet of the second cyclone separator 11, and the smoke inlet of the second cyclone separator 11 is connected with the smoke outlet of the third rotary kiln 13, and the composite combustion chamber A smoke exhaust port is provided at one end of 18 close to the bucket elevator 16, and the smoke exhaust port is connected to the smoke inlet on the third rotary kiln 13, and the smoke outlet on the first rotary kiln 5 is connected to the heat exchanger 27. The bottom of the heat exchanger 27 is connected to an induced draft fan 28, and the output end of the induced draft fan 28 is connected to a flue gas processor 29, so that the high-temperature flue gas after combustion in the composite combustion chamber 18 bypasses the outer shell of the third rotary kiln 13, the outer shell of the second cyclone separator 11, the outer shell of the second rotary kiln 10, the outer shell of the first cyclone separator 8, and the outer shell of the first rotary kiln 5 in sequence under the operation of the induced draft fan 28, and then enters the heat exchanger 27 to exchange heat with the air, and finally enters the flue gas processor 29 for flue gas treatment, completing the whole cycle and discharging pollution-free gas.

[0044] The use process of a waste plastic catalytic cracking oil conversion system provided by the present invention is as follows: the plastic waste is first crushed by a crusher 1, and then enters the feed port 3 and the screw feeder 4 in sequence under the action of a conveyor belt 2. The screw feeder 4 evenly feeds the plastic into the first rotary kiln 5 for preliminary pyrolysis, and the control motor 7 drives the rotating blades 6 to rotate, thereby achieving the purpose of separating the agglomerated large particles. The remaining mixture of the reaction is separated by the first cyclone separator 8, and the first control valve 9 can control the catalyst, oil-gas mixture, carbon slag, ash and unreacted residual materials to fall into the second rotary kiln 10 for secondary pyrolysis, and the remaining mixture of the reaction is separated by the second cyclone separator 11. The second control valve 12 can control the carbon deposit catalyst particles, carbon residue, ash residue and the remaining materials that have not reacted completely to continue to fall into the third rotary kiln 13 for three pyrolysis. The remaining mixture is separated by the third cyclone separator 14. The microwave heating device 15 outside the third cyclone separator 14 has the characteristics of rapid start and stop and rapid heating. During the process, the carbon residue from the third rotary kiln 13 is sampled and tested. If there is volatile matter, that is, the material has not reacted completely, it is turned on. If there is no volatile matter, that is, the reaction is complete, it is closed, and the carbon residue can be used as a wave absorber. Then the carbon deposit catalyst particles, carbon residue, and ash residue are lifted to the top of the composite combustion chamber 18 by the bucket elevator 16, and the high-temperature gas separated by the three cyclone separators is first concentrated in the gas mixing chamber 17, and then enters the first cooling tower 20. After spraying under the operation of the first circulating oil pump 21, the heavy tar with a condensation temperature between 350-450°C in the oil-gas mixture is condensed. At the same time, the condensed heavy tar enters the second rotary kiln 10 under the operation of the first circulating oil pump 21. On the one hand, it can prevent the waste plastic from coking during the pyrolysis process, and on the other hand, it can pyrolyze the heavy components in the pyrolysis products again to further crack them into light components. The uncondensed light component gas continues to enter the second cooling tower 22. After spraying under the operation of the second circulating oil pump 23, the diesel with a condensation temperature between 180-350°C in the oil-gas mixture is condensed. The uncondensed light component gas continues to enter the third cooling tower 24. After spraying under the operation of the third circulating oil pump 25, the gasoline with a condensation temperature below 180°C in the oil-gas mixture is condensed. The non-condensed hydrogen, methane and other combustible gases finally enter the contraction position of the convergent nozzle 19. The air blower 26 first preheats the air required for combustion through the heat exchanger 27, and then preheats it again through the third cooling tower 24, the second cooling tower 22, and the first cooling tower 20 in turn, and finally enters the composite combustion chamber 18 through the convergent nozzle 19.Carbon deposited catalyst particles and carbon slag are burned in the composite combustion chamber 18, and the ceramic balls are heated by burning natural gas and hot flue gas is generated. Then the ceramic balls enter the first rotary kiln 5, the second rotary kiln 10 and the third rotary kiln 13 in order from large to small in particle size, so that the low-temperature large particles (3 cm), medium-temperature medium particles (1 cm) and high-temperature small particles (0.5 cm) catalysts remaining from the combustion enter the three pipes from near to far under the action of gas purge. Among them, the low-temperature large particles (3 cm) fall into the first rotary kiln 5, the medium-temperature medium particles (1 cm) fall into the second rotary kiln 10, and the high-temperature small particles (0.5 cm) fall into the third rotary kiln 13. The high-temperature flue gas after combustion in the composite combustion chamber 18 bypasses the outer shell of the third rotary kiln 13, the outer shell of the second cyclone separator 11, the outer shell of the second rotary kiln 10, the outer shell of the first cyclone separator 8, and the outer shell of the first rotary kiln 5 in sequence under the operation of the induced draft fan 28, and then enters the heat exchanger 27 to exchange heat with the air, and finally enters the flue gas processor 29 for flue gas treatment, completing the whole cycle and discharging pollution-free gas.

[0045] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the present invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A waste plastic catalytic cracking oil system, characterized in that: The invention comprises a pulverizer (1), wherein a conveyor belt (2) is fixed to the discharge port of the pulverizer (1), a screw feeder (4) is arranged at one end of the bottom of the conveyor belt (2), a feed port (3) is provided at the top of the screw feeder (4) near one end of the conveyor belt (2), the inner side of the feed port (3) is rotatably connected to the screw feeder (4), the outlet at the bottom of one end of the screw feeder (4) is connected to a first rotary kiln (5) through a first pipeline, the interior of the first rotary kiln (5) is rotatably connected to a rotary blade (6), a control motor (7) is fixed to one end of the first rotary kiln (5), the output end of the control motor (7) is connected to the rotary blade (6), and the first rotary kiln (5) The output port at one end is connected to a first cyclone separator (8); the bottom of the first rotary kiln (5) is connected to a second rotary kiln (10) via a second pipeline; the output end of the second rotary kiln (10) is connected to a second cyclone separator (11); the output end of the second cyclone separator (11) is connected to a third rotary kiln (13) via a third pipeline; the output end of the third rotary kiln (13) is connected to a third cyclone separator (14); a microwave heating device (15) is fixed to the outside of the third cyclone separator (14); the output end of the third cyclone separator (14) is connected to a bucket elevator (16); and the output end at the top of the bucket elevator (16) is connected to a composite combustion chamber (18).

2. A waste plastic catalytic cracking oil system according to claim 1, characterized in that: A plurality of ceramic balls with different particle sizes are placed inside the composite combustion chamber (18).

3. A waste plastic catalytic cracking oil system according to claim 1, characterized in that: The diameter of the rotating blade (6) increases gradually from the end far from the control motor (7) to the end close to the control motor (7), and the minimum gap between the rotating blade (6) and the inner wall of the first rotary kiln (5) is 5 cm.

4. A waste plastic catalytic cracking oil system according to claim 1, characterized in that: A first control valve (9) is provided at the bottom of the first cyclone separator (8), and a second control valve (12) is provided at the bottom of the second cyclone separator (11).

5. A waste plastic catalytic cracking oil system according to claim 1, characterized in that: The tops of the first cyclone separator (8), the second cyclone separator (11) and the third cyclone separator (14) are all connected to a gas mixing chamber (17).

6. A waste plastic catalytic cracking oil system according to claim 5, characterized in that: The output end of the gas mixing chamber (17) is connected to a first cooling tower (20), one end of the first cooling tower (20) is fixed with a first circulating oil pump (21), the input end of the first circulating oil pump (21) is connected to the bottom end of the first cooling tower (20), the output end of the first circulating oil pump (21) is connected to a spray head inside the first cooling tower (20), the output end of the first circulating oil pump (21) is also connected to a second rotary kiln (10), the top of the first cooling tower (20) is connected to a second cooling tower (22) via a pipeline, one end of the second cooling tower (22) is fixed with a second circulating oil pump (23), the top of the second cooling tower (22) is connected to a third cooling tower (24) via a pipeline, one end of the third cooling tower (24) is fixed with a third circulating oil pump (25), the top of the third cooling tower (24) is connected to a convergent-divergent nozzle (19) via a pipeline, and the convergent-divergent nozzle (19) is connected to the composite combustion chamber (18).

7. A waste plastic catalytic cracking oil system according to claim 6, characterized in that: It also includes an air blower (26), the output end of which is connected to a heat exchanger (27), and the output end of the heat exchanger (27) sequentially enters the interior of the third cooling tower (24), the second cooling tower (22) and the first cooling tower (20) and is then connected to a convergent-divergent nozzle (19).

8. The waste plastic catalytic cracking oil system according to claim 1, characterized in that: The bottom of the composite combustion chamber (18) is provided with a low-temperature particle pipeline, a medium-temperature particle pipeline and a high-temperature particle pipeline in sequence from one end to the other end, the bottom of the low-temperature particle pipeline is connected to the first pipeline, the bottom of the medium-temperature particle pipeline is connected to the second pipeline, and the bottom of the high-temperature particle pipeline is connected to the third pipeline.

9. A waste plastic catalytic cracking oil system according to claim 1, characterized in that: The first rotary kiln (5), the first cyclone separator (8), the second rotary kiln (10), the second cyclone separator (11) and the third rotary kiln (13) are all provided with smoke outlets at the top of one end, and the first rotary kiln (5), the first cyclone separator (8), the second rotary kiln (10), the second cyclone separator (11) and the third rotary kiln (13) are all provided with smoke inlets at the bottom of one end. The composite combustion chamber (18) is provided with a smoke exhaust port at one end close to the bucket elevator (16), and the smoke exhaust port is connected to the smoke inlet of the third rotary kiln (13). The smoke outlet of the first rotary kiln (5) is connected to a heat exchanger (27), and the bottom of the heat exchanger (27) is connected to an induced draft fan (28), and the output end of the induced draft fan (28) is connected to a smoke processor (29).

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