A waste plastic pyrolysis oil production system

Abstract

The present invention provides a waste plastic pyrolysis oil production system. It includes a solid heat carrier circulation heating system, an oil and gas separation and purification system, and a bipolar dust removal and catalytic body integrated system; the pyrolysis reactor has an automatic coking function, and the flow of high-temperature solid heat carrier entering the pyrolysis reactor is controlled by a flow distributor, thereby controlling the heat entering the pyrolysis reactor, so that the pyrolysis reaction has a regulating function and the reaction process is controllable. The solid heat carrier furnace is provided with a bottom combustion organization module, and a combustion scheme of directly spraying gas into the furnace is adopted, which reduces the setting of external burners, simplifies the process flow, and reduces equipment costs. A combined dust removal mode of spiral dust collector + high-temperature dust collector is adopted, with high dust removal efficiency, anti-blocking of equipment and pipelines, and high device operation stability. A catalyst is built in the high-temperature dust collector, and catalytic quality improvement promotes secondary cracking of pyrolysis oil and gas, which can achieve product lightness and improve oil quality.

Description

Technical Field

[0001] The invention belongs to the technical field of organic solid waste resource utilization, and specifically relates to a waste plastic pyrolysis oil production system. Background Art

[0002] Waste plastics have complex compositions and are basically difficult to recycle through regeneration technology. Reduction and harmless disposal through landfill or incineration technology have low resource utilization rates, severe secondary pollution and high carbon emissions.

[0003] The pyrolysis oil technology of waste plastics has outstanding resource advantages and environmental protection performance. It can convert non-recyclable waste plastics into plastic oil, realize the chemical recycling of waste plastics and effectively reduce carbon emissions. It has attracted attention in the industry in recent years.

[0004] Existing waste plastic pyrolysis technologies mostly use flue gas external heating, and the reactors are mostly in the form of external jacket or internal and external jacket, relying on high-temperature flue gas as a heat source for indirect heat exchange. There are difficulties such as low heat exchange efficiency, low processing efficiency, and easy coking in the process, which cannot be applied in large-scale industrial applications. At the same time, due to the large number of impurities in waste plastics, the gas dust removal efficiency in the existing process is low, which leads to easy blockage of equipment and pipelines, frequent equipment maintenance, and difficulty in long-term stable operation. In addition, the quality of waste plastic oil products obtained by the existing technology is uneven, the content of heavy components in the oil products is high, the quality of the oil products is poor, and it brings certain difficulties to the subsequent use of oil products. In the catalytic pyrolysis technology, the catalyst is often directly mixed with the waste plastic, which has the problem that the catalyst is difficult to recover when mixed with hot carbon deposits, and the catalyst is quickly deactivated by dust attached to carbon deposits.

[0005] In summary, it has become an urgent need to develop a new pyrolysis oilification technology for non-renewable waste plastics, transform non-renewable solid waste plastics into liquid oil with utilization value through pyrolysis, solve the technical difficulties of waste plastic oilification process that is difficult to scale up and continue, and the equipment is prone to coking and clogging, and has poor operating stability, and realize the harmlessness, reduction and resource utilization of non-renewable waste plastics. Summary of the invention

[0006] The technical problem solved by the present invention is to overcome the defects in the prior art and provide a waste plastic pyrolysis oil production system with high efficiency heat exchange, prevention of coking and carbon deposition, integrated dust removal and catalysis, change the current situation of system blockage, obtain lightweight high-value-added oil products, and realize continuous and stable operation of the device.

[0007] The technical solution of the present invention is: a waste plastic pyrolysis oil production system, including a solid heat carrier circulation heating system, an oil and gas separation and purification system, and a bipolar dust removal and catalytic body integrated system;

[0008] The solid heat carrier circulation heating system includes a pyrolysis reactor, a solid heat carrier furnace, a gas-solid separator, a flow distributor, a return feeder, and a bottom combustion organization module; the bipolar dust removal and catalytic body integrated system includes a spiral dust collector and a dust collector;

[0009] The solid heat carrier furnace heats the solid heat carrier in the furnace and promotes the combustion of pyrolysis carbon under the action of the bottom combustion organization module. The high-temperature flue gas carries the high-temperature solid heat carrier into the gas-solid separator. In the gas-solid separator, the solid heat carrier and the high-temperature flue gas are separated. The separated flue gas is discharged from the outlet of the gas-solid separator and enters the subsequent flue gas purification process. The solid heat carrier enters the flow distributor from the lower outlet of the gas-solid separator; the flow distributor controls the flow of solid heat carrier entering the pyrolysis reactor and returning to the solid heat carrier furnace according to the feed amount and the final pyrolysis temperature; the waste plastic and the solid heat carrier from the flow distributor are separated. The solid heat carrier enters the pyrolysis reactor at the same time, and the waste plastic is heated and pyrolyzed in the pyrolysis reactor, and converted into pyrolysis oil, pyrolysis gas, and pyrolysis carbon; the pyrolysis carbon and the cooled solid heat carrier enter the return feeder from the lower outlet of the pyrolysis reactor together, and enter the solid heat carrier furnace through the outlet of the return feeder; the mixed oil and gas in the pyrolysis reactor first enter the spiral ash cleaner, and then enter the dust collector through the spiral ash cleaner. The two-stage dust removal combination completes the dust removal of the high-temperature mixed oil and gas; the dust collector inputs the dust-removed oil and gas into the oil and gas separation and purification system to complete the oil and gas separation, and the separated non-condensable gas enters the solid heat carrier furnace as fuel for combustion.

[0010] Preferably, the flow distributor contains three interconnected cavities: a fluidizing chamber, a pyrolysis chamber, and a bypass chamber. The heat carrier enters the fluidizing chamber from the heat carrier inlet, and enters two logistics outlet channels via the pyrolysis chamber and the bypass chamber respectively. The two logistics outlet channels are a heat carrier outlet pyrolysis path and a heat carrier outlet bypass path, wherein the heat carrier outlet pyrolysis path delivers the solid heat carrier into the pyrolysis reactor, and the heat carrier outlet bypass path delivers the solid heat carrier into the solid heat carrier furnace; the heat carrier outlet pyrolysis path is provided with a pyrolysis path high-temperature plug-in valve, and the heat carrier outlet bypass path is provided with a bypass path high-temperature plug-in valve.

[0011] Preferably, the flow distributor is provided with a bypass channel loosening air inlet, a pyrolysis channel loosening air inlet and a fluidizing air inlet at the bottom; the bypass loosening air is blown into the bypass cavity through the bypass channel loosening air inlet, and then the heat carrier is blown to the heat carrier outlet bypass cavity; the pyrolysis channel loosening air is blown into the pyrolysis cavity from the pyrolysis channel loosening air inlet, and then the heat carrier is blown to the heat carrier outlet pyrolysis path; the fluidizing air enters the fluidizing cavity from the fluidizing air inlet, maintains the flow state of the bed in the fluidizing cavity, and avoids particle aggregation and blockage; according to the feed amount and the final pyrolysis temperature, the opening of the high-temperature gate valve of the pyrolysis path and the high-temperature gate valve of the bypass path are adjusted, and the loosening air and fluidizing air flow rates are adjusted in coordination, thereby controlling the flow rate of the high-temperature solid heat carrier entering the pyrolysis reactor, controlling the heat entering the pyrolysis reactor, and realizing controllable regulation of the pyrolysis reaction.

[0012] Preferably, the bottom combustion organization module includes a gas pipeline, a gas hood, a combustion-supporting air pipeline, a combustion-supporting air hood and a bottom ignition burner;

[0013] When starting the furnace, turn on the bottom ignition burner. When the pyrolysis system is fed and the output is running stably, turn off the bottom ignition burner and enable the gas pipeline. The gas is sprayed directly into the dense phase area of ​​the furnace through the gas pipeline through the gas wind cap, and the combustion-supporting air is blown into the furnace through the combustion-supporting air pipeline through the combustion-supporting air hood. The gas and the combustion-supporting air meet in the dense phase area and burn under the high temperature environment of the dense phase area.

[0014] Preferably, the oil-gas separation and purification system has both water washing and oil washing spray cooling functions; when the system is put into operation after materials are put into operation, oil washing spray cooling is first used. If the gas phase outlet temperature of the first-level oil-gas separation tower rises above the set threshold or the spray circulation flow rate through the first-level circulation pump decreases, it is switched to water washing, otherwise oil washing continues.

[0015] Preferably, the oil-gas separation and purification system comprises a primary oil-gas separation tower, a secondary oil-gas separation tower, a tertiary oil-gas separation tower, a primary oil-water separator, and a secondary oil-water separator;

[0016] In the oil washing spray cooling, the primary oil and gas separation tower, the secondary oil and gas separation tower, and the tertiary oil and gas separation tower are put into use; the outlet gas temperature above the primary oil and gas separation tower is controlled to be higher than the dew point temperature of water, so that the pyrolysis oil is condensed and settled in the primary oil and gas separation tower and the water vapor is kept from condensing and precipitating; the mixed gas without the pyrolysis oil enters the secondary oil and gas separation tower and the tertiary oil and gas separation tower in turn, so as to condense and precipitate the water vapor in the mixed gas, remove the moisture in the mixed gas, and remove the chloride in the pyrolysis gas, so as to complete the purification of the pyrolysis gas;

[0017] In the water-washing spray cooling, the first-stage oil-gas separation tower uses water as the spray liquid. The spray liquid directly contacts and exchanges heat with the high-temperature mixed oil and gas, so that the pyrolysis oil and water vapor in the mixed gas condense and settle. The cooled liquid and the spray liquid flow from the first-stage oil-gas separation tower to the first-stage oil-water separator and the second-stage oil-water separator in sequence. In the two-stage oil-water separator, the pyrolysis oil and the spray water are separated. The separated spray water is cooled by the first-stage heat exchanger and then continues to be circulated as a cooling medium to form a spray liquid cycle; the gas discharged from the top of the first-stage oil-gas separation tower enters the second-stage oil-gas separation tower and the third-stage oil-gas separation tower in sequence to further remove the residual pyrolysis oil and water to obtain clean pyrolysis gas;

[0018] In both methods, water is used as the spraying liquid in the secondary oil-gas separation tower and the tertiary oil-gas separation tower to fully condense the residual water vapor therein, and the dehydrated non-condensable gas enters the solid heat carrier furnace and is burned as fuel.

[0019] Preferably, the spray liquid temperature of the first-stage oil and gas separation tower is controlled at 65-75°C, the bottom temperature of the first-stage oil and gas separation tower can be controlled at 100-105°C, the spray liquid temperature of the second-stage oil and gas separation tower is controlled at 50-55°C, the spray liquid temperature of the tertiary oil and gas separation tower is controlled at 5-15°C, and the temperature of the non-condensable gas discharged from the tertiary oil and gas separation tower is controlled at 20-23°C.

[0020] Preferably, the dust collector comprises a shell, a fixed catalyst bed, a filter element, and a nitrogen injection system;

[0021] The nitrogen blowing system includes a nitrogen blowing main pipe, a nitrogen backflush structure, and a nitrogen supply unit outside the housing, which is used to backflush the filter cake structure formed on the outside of the filter element and discharge it from the bottom outlet of the housing;

[0022] The filter element is installed inside the housing, dividing the inner cavity of the housing into a pre-filter cavity and a post-filter cavity; a nitrogen backflush structure is installed on a nitrogen injection main pipe inside the housing to inject nitrogen from the filter element port of the filter element into the interior of the filter element; a fixed catalyst bed is installed in the post-filter cavity; the fixed catalyst bed is filled with a catalyst;

[0023] The high-temperature pyrolysis oil and gas from unpurified waste plastics enters from the bottom of the shell, and the dust in the pyrolysis oil and gas is filtered and captured by the filter element and discharged from the bottom outlet of the shell. The filtered pyrolysis oil and gas enter the fixed catalyst bed, where the pyrolysis oil and gas react with the catalyst to achieve catalytic quality improvement of the oil and gas, and then the oil and gas are discharged from the top outlet of the shell.

[0024] Preferably, the fixed catalyst bed is composed of a catalyst bed flower plate, a catalyst bed baffle, and a catalyst bed fixing structure; the catalyst bed flower plate is provided with small holes, the size of the small holes allowing pyrolysis oil and gas to pass through while preventing the catalyst from falling; a catalyst bed baffle is arranged in the bed for partitioning and fixing the catalyst; a fixed catalyst bed fixing structure is arranged along the inner wall of the device on the upper and lower sides of the catalyst bed for fixing and disassembling the catalyst bed; the diameter of the small hole is ≤10mm, and the catalyst is a shaped porous solid particle with a certain physical strength, and the particle size is 10 to 50mm.

[0025] Preferably, the dust collector further comprises a charring system; the charring system burns the carbon deposits in the catalyst gaps by introducing oxygen into the shell, thereby achieving catalyst regeneration by high-temperature charring;

[0026] The charring system includes an oxygen or air flow meter and a normal temperature nitrogen flow meter, an oxygen or air regulating valve and a normal temperature nitrogen regulating valve, a cavity temperature monitoring and a filter element temperature monitoring, a cavity pressure monitoring before filtration, a cavity pressure monitoring after filtration and a cavity outlet oxygen content monitoring;

[0027] The amount of oxygen and nitrogen introduced into the shell is monitored by an oxygen or air flow meter and a normal temperature nitrogen flow meter respectively, and the oxygen and nitrogen flow rates are controlled by an oxygen or air regulating valve and a normal temperature nitrogen regulating valve respectively, thereby realizing the control of the oxygen content at the shell outlet; the oxygen content monitoring at the cavity outlet is used to monitor the change of oxygen content in the shell during the catalyst regeneration process; the cavity pressure monitoring before filtration and the cavity pressure monitoring after filtration are used to monitor the pressure change during the catalyst regeneration process; cavity temperature monitoring and filter element temperature monitoring are provided to monitor the temperature change during the catalyst regeneration process, and when the pressure change / temperature change exceeds the preset range, normal temperature nitrogen is introduced into the shell; the high pressure alarm value is 15 to 20 kPa.G, and the low pressure alarm value is -10 to 5 kPa.G; the charring temperature is 400 to 600°C; the oxygen content does not exceed 1% during the charring process.

[0028] Preferably, the starting methods of the nitrogen blowing system include: one is starting after the pressure difference between the pre-filter cavity and the post-filter cavity reaches a preset value, and the other is starting after setting a fixed time interval; when the starting conditions are met, the high-pressure nitrogen fills the internal space of the filter element in a short time, so that the filter element is filled with pressure and shakes, and the filter cake structure formed on the outside of the filter element is blown back and dropped; the preset value ranges from 500 to 3000 Pa; the time interval is generally 10 to 30 minutes; the pressure of the high-pressure nitrogen is 0.3-0.5MPa.G; the short time is 1 to 5 seconds.

[0029] The beneficial effects of the present invention compared with the prior art are:

[0030] The system of the present invention can achieve high-yield conversion of waste plastics into plastic oil. It adopts a combined dust removal mode of spiral dust collector + high-temperature dust collector, has high dust removal efficiency, prevents equipment and pipelines from being blocked, and has high device operation stability. The high-temperature dust collector has a built-in catalyst, and catalytic quality improvement promotes secondary cracking of pyrolysis oil and gas, which can achieve product lightweighting, improve oil quality, and enhance the economy of waste plastic oil production. At the same time, the dust removal and catalysis are integrated, the process flow is simple, the equipment is compact, and the footprint is small.

[0031] The present invention adopts a solid heat carrier circulation heating method to supply energy to the system. The pyrolysis reactor has an automatic coke removal function. The flow of high-temperature solid heat carrier entering the pyrolysis reactor is controlled by a flow distributor, thereby controlling the heat entering the pyrolysis reactor, so that the pyrolysis reaction has a regulating function and the reaction process is controllable. The solid heat carrier furnace is provided with a bottom combustion organization module, and a combustion scheme of directly injecting gas into the furnace is adopted, which reduces the setting of external burners, simplifies the process flow, and reduces equipment costs.

[0032] The oil-gas separation and purification system adopted in the present invention adopts a three-stage spray cooling method, has dual functions of water washing and oil washing, can realize multiple functions of gas-liquid separation, oil-water separation, and chloride removal, can efficiently recover pyrolysis oil, and obtain clean non-condensable gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the device of the present invention;

[0034] Figure 2 It is a schematic diagram of the dust collector of the present invention;

[0035] Figure 3 This is a schematic diagram of the structure of a filter element with a sintered catalyst coating of a metal membrane or a ceramic membrane according to the present invention;

[0036] Figure 4 This is a schematic diagram of the fixed catalyst bed structure of the present invention;

[0037] Figure 5 It is a flow chart of oil and gas separation and purification system.

[0038] Figure 6 It is the structure diagram of the flow distributor.

[0039] Figure 7 This is the module structure diagram of the bottom combustion organization. DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with the embodiments.

[0041] A waste plastic pyrolysis oil production system, including a solid heat carrier heating and combustion system, an oil and gas separation and purification system, and a two-stage dust removal and catalytic quality improvement integrated system.

[0042] The pyrolysis reactor 1 is the core pyrolysis unit, and the solid heat carrier furnace 5, the gas-solid separator 6, the flow distributor 7, and the return feeder 8 together constitute a circulating heating system of the solid heat carrier, which cyclically provides the pyrolysis reactor 1 with the heat required for pyrolysis. The spiral dust collector and the high-temperature dust collector constitute an integrated system of bipolar dust removal and catalytic body, and the primary oil-gas separation tower 41, the secondary oil-gas separation tower 42, the tertiary oil-gas separation tower 43, the primary oil-water separator 44, and the secondary oil-water separator 45 constitute an oil-gas separation purification system.

[0043] A gas outlet above the pyrolysis reactor 1 is connected to the gas inlet of the spiral ash cleaner 2, the gas outlet of the spiral ash cleaner 2 is connected to the inlet of the high-temperature dust collector 3, the outlet of the high-temperature dust collector 3 is connected to the gas phase inlet of the oil-gas separation and purification system 4, the gas phase outlet above the oil-gas separation and purification system 4 is connected to the solid heat carrier furnace 5, the gas-solid mixed outlet of the solid heat carrier furnace 5 is connected to the inlet of the gas-solid separator 6, the lower outlet of the gas-solid separator 6 is connected to the inlet of the flow distributor 7, an outlet of the flow distributor 7 is connected to the pyrolysis reactor 1, the lower outlet of the pyrolysis reactor 1 is connected to the upper inlet of the return feeder 8, the lower outlet of the return feeder 8 is connected to the solid heat carrier furnace 5, and a bottom combustion organization module 9 is provided at the bottom of the solid heat carrier furnace 5.

[0044] The outlet of the high-temperature dust collector 3 is connected to the lower left gas phase inlet of the first-level oil-gas separation tower 41, the top gas phase outlet of the first-level oil-gas separation tower 41 is connected to the lower left gas phase inlet of the second-level oil-gas separation tower 42, the top gas phase outlet of the second-level oil-gas separation tower 42 is connected to the lower left gas phase inlet of the tertiary oil-gas separation tower 43, and the top gas phase outlet of the tertiary oil-gas separation tower 43 is connected to the solid heat carrier furnace 5.

[0045] The bottom outlet of the primary oil-gas separation tower 41 is connected to the inlet of the primary oil-water separator 44, the outlet of the primary oil-water separator 44 is connected to the inlet of the secondary oil-water separator 45, the outlet of the secondary oil-water separator 45 is connected to the inlet of the water-washing circulation pump P4, the outlet of the water-washing circulation pump P4 is connected to the inlet of the primary heat exchanger E1, and the outlet of the primary heat exchanger E1 is connected to the primary oil-gas separation tower 41. A water-washing circulation pump inlet valve F4 and a water-washing circulation pump outlet valve F5 are respectively arranged before and after the water-washing circulation pump P4.

[0046] The liquid phase outlet at the lower right part of the primary oil-gas separation tower 41 is connected to the inlet of the primary circulation pump P1, and the outlet of the primary circulation pump P1 is connected to the primary heat exchanger E1. A primary oil-gas separation tower bottom valve F1 is provided at the bottom of the primary oil-gas separation tower 41, and a primary circulation pump inlet valve F2 and a primary circulation pump outlet valve F3 are provided before and after the primary circulation pump P1, respectively.

[0047] The liquid phase outlet at the bottom of the secondary oil-gas separation tower 42 is connected to the inlet of the secondary circulation pump P2 , the outlet of the secondary circulation pump P2 is connected to the inlet of the secondary heat exchanger E2 , and the outlet of the secondary heat exchanger E2 is connected to the secondary oil-gas separation tower 42 .

[0048] The liquid phase outlet at the bottom of the tertiary oil-gas separation tower 43 is connected to the inlet of the tertiary circulation pump P3, the outlet of the tertiary circulation pump P3 is connected to the inlet of the tertiary heat exchanger E3, and the outlet of the tertiary heat exchanger E3 is connected to the tertiary oil-gas separation tower 43.

[0049] 1. Solid heat carrier heating and combustion system

[0050] The waste plastic and the high-temperature solid heat carrier from the flow distributor 7 enter the pyrolysis reactor 1 at the same time. The waste plastic is heated and pyrolyzed, and is converted into pyrolysis oil, pyrolysis gas, and pyrolysis carbon. The pyrolysis reactor 1 is equipped with a spiral to convey the material forward. The pyrolysis carbon and the cooled solid heat carrier enter the return feeder 8 from the lower outlet of the pyrolysis reactor 1, and enter the solid heat carrier furnace 5 through the outlet of the return feeder 8. The high-temperature heat carrier has the characteristics of high hardness, high strength, and large heat capacity. It provides a heat source for the pyrolysis of waste plastics. At the same time, it plays a role in clearing coke during the mixing and stirring process with waste plastics, which can effectively avoid coking in the reactor and solve the problem of easy coking and carbon deposition in the pyrolysis process in the current technology. In specific operation cases, the solid heat carrier can be quartz sand, river sand, ceramic balls, silicon carbide, etc.

[0051] The solid heat carrier furnace 5 adopts a multi-stage gas arrangement scheme to recycle the pyrolysis gas generated by the system.

[0052] Furthermore, a bottom combustion organization module 9 is provided at the bottom of the solid heat carrier furnace 5, such as Figure 7 As shown, it includes a gas pipeline 91, a gas hood 92, a bottom combustion-supporting air pipeline 93, a combustion-supporting air hood 94 and a bottom ignition burner 95. Furthermore, the multi-layer gas pipelines provided in the solid heat carrier furnace 5 include a supplementary gas pipeline. When the system cannot maintain energy balance, natural gas is turned on as a supplementary fuel to supply energy to the system. In the bottom combustion organization module 9, the bottom combustion-supporting air pipeline 93 is connected to the bottom air chamber 96, and an ignition burner combustion-supporting air pipeline 98 is provided at the upper left of the bottom ignition burner 95. The ignition burner combustion-supporting air pipeline 98 is connected to the bottom combustion-supporting air pipeline 93, and the bottom ignition burner 95 is connected to the bottom air chamber 96 on the right. An air distribution plate 99 is provided between the bottom air chamber 96 and the dense phase area 97, and a combustion-supporting air hood 94 and a gas hood 92 are provided on the air distribution plate. The gas pipeline 91 is connected to the dense phase area 97 through the gas hood.

[0053] When the furnace is started, the bottom ignition burner 95 is turned on. When the pyrolysis system is fed and the output is stable, the bottom ignition burner 95 is turned off and the gas pipeline 91 is activated. The gas is directly sprayed into the dense phase area of ​​the furnace through the gas pipeline 91 through the gas hood 92, and the combustion-supporting air is blown into the furnace through the combustion-supporting air pipeline 93 through the combustion-supporting air hood 94, changing the traditional scheme of premixing the gas and the combustion-supporting air in advance. The gas and the combustion-supporting air meet in the dense phase area and burn under the high temperature environment of the dense phase area. In actual operation, the gas pipeline 91 can use pyrolysis gas or natural gas. The present invention subverts the traditional scheme of external burners. The gas does not need to be premixed with air for combustion outside the furnace, which reduces equipment and simplifies the process flow. A slag discharge port is set at the bottom of the solid heat carrier furnace 5, and the ash produced by the combustion of pyrolysis carbon and a small amount of solid heat carrier loss are discharged from the bottom slag discharge port.

[0054] In the solid heat carrier furnace 5, pyrolysis gas and pyrolysis carbon are burned as fuel, the energy of pyrolysis carbon is fully utilized, and the solid heat carrier is reheated. The high-temperature flue gas carries the high-temperature solid heat carrier into the gas-solid separator 6, where the solid heat carrier and the high-temperature flue gas are separated. The separated flue gas enters the flue gas purification process, and the solid heat carrier enters the flow distributor 7 from the lower outlet of the gas-solid separator 6.

[0055] The flow distributor 7 is used to control the circulation flow of the high-temperature solid heat carrier. The flow of the high-temperature solid heat carrier can be distributed according to the feed amount and the final pyrolysis temperature to input the heat required for pyrolysis into the pyrolysis reactor. Figure 6 As shown, the flow distributor 7 is provided with two logistics outlet channels, namely, the heat carrier outlet pyrolysis path 72 and the heat carrier outlet bypass path 73, wherein the heat carrier outlet pyrolysis path 72 delivers the solid heat carrier into the pyrolysis reactor 1, and the heat carrier outlet bypass path 73 delivers the solid heat carrier into the solid heat carrier furnace 5. The heat carrier outlet pyrolysis path 72 is provided with a pyrolysis path high-temperature gate valve 74, and the heat carrier outlet bypass path 73 is provided with a bypass path high-temperature gate valve 75. A bypass path loosening air inlet 76, a pyrolysis path loosening air inlet 77, and a fluidizing air inlet 78 are provided at the bottom of the flow distributor 7, the bypass path loosening air inlet 76 is connected to the bypass chamber 79, the pyrolysis path loosening air inlet 77 is connected to the pyrolysis chamber 710, and the fluidizing air inlet 78 is connected to the fluidizing chamber 711.

[0056] In actual operation, the pyrolysis path loosening wind enters the pyrolysis chamber 710 from the pyrolysis path loosening wind inlet 77, and then blows the heat carrier to the heat carrier outlet pyrolysis path 72; the bypass path loosening wind enters the bypass chamber 79 from the bypass path loosening wind inlet 76, and then blows the heat carrier to the heat carrier outlet bypass path 73; the fluidizing wind enters the fluidizing chamber 711 from the fluidizing wind inlet, and maintains the fluid state of the bed layer in the fluidizing chamber 711 to avoid particle aggregation and blockage. In actual operation, according to the feed amount and the final temperature of pyrolysis, the opening of the two gate valves is adjusted, and the loosening wind and fluidizing wind flow rates are adjusted in coordination, thereby controlling the flow rate of the high-temperature solid heat carrier entering the pyrolysis reactor 1, controlling the heat entering the pyrolysis reactor 1, and realizing controllable regulation of the pyrolysis reaction.

[0057] The heat carrier enters the heat carrier inlet passage 71 from top to bottom. The design of the heat carrier outlet pyrolysis passage 72 and the heat carrier outlet bypass passage 73 should ensure the smooth flow of solid materials. Generally, a straight pipeline design with an inclined downward direction can be adopted. The specific inclination angle when inclined downward depends on the actual engineering requirements. The angle between the heat carrier outlet pyrolysis passage 72 and the heat carrier outlet bypass passage 73 depends on the actual engineering requirements such as equipment layout.

[0058] In a specific case, the effective flow cross-sections of the pyrolysis path high temperature gate valve 74 and the bypass path high temperature gate valve 75 can be circular, elliptical, or any other shape that can satisfy the material flow.

[0059] Furthermore, in order to meet the requirement of long-term stable operation at high temperature, the channel of the flow distributor 7 in contact with the material should be provided with a casting material, that is, Figure 6 The area within the middle dotted line is the effective logistics channel.

[0060] A slag discharge port is arranged at the bottom of the solid heat carrier furnace 5, and the ash produced by the combustion of pyrolytic carbon and a small amount of lost solid heat carrier are discharged from the slag discharge port at the bottom.

[0061] 2. Two-stage dust removal and catalytic quality improvement integrated system

[0062] The two-stage dust removal system of spiral dust collector 2 + high-temperature dust collector 3 is used to remove dust from pyrolysis gas in an efficient and fine manner. The high-temperature mixed oil and gas generated by pyrolysis is discharged from the outlet of the pyrolysis reactor 1, first enters the spiral dust collector 2, and then enters the high-temperature dust collector 3 through the spiral dust collector 2. The two-stage dust removal combination completes the dust removal of the high-temperature mixed gas. The spiral dust collector 2 is equipped with a shaftless spiral, which can transport the deposited particulate matter into the pyrolysis reactor 1. The setting of the spiral dust collector 2 avoids the phenomenon that the traditional horizontal pipe section is prone to opportunity blockage.

[0063] The high-temperature dust collector 3 uses a metal membrane filter element or a ceramic membrane filter element, which has the characteristics of high temperature resistance and corrosion resistance, high filtering accuracy, and can achieve fine dust removal. Specifically, Figure 2As shown, the dust collector includes a device housing a, a fixed catalyst bed b, a high-temperature nitrogen pulse valve c, a high-temperature nitrogen injection main pipe d, a high-temperature nitrogen backflush structure e, a filter element f, a regulating valve g, a flow meter h, and a temperature and pressure monitor i;

[0064] The shell a is provided with a heating source a1 and a heat preservation layer a2 from the inside to the outside respectively; a filter element f is provided at the lower part of the device, and the filter element f is fixed on the filter element fixing plate f4 by a bolt structure, and the filter element fixing plate f4 is welded to the inner wall of the shell a, and the filter element f comprises a sintered catalyst coating f1, a filter element skeleton f2, a filter element fixing bolt f3 and a filter element fixing plate f4; a high-temperature nitrogen backflush structure e is provided above the filter element, and the high-temperature nitrogen backflush structure e adopts a Venturi structure, and the upper end face of the opening of the structure is fixed on the high-temperature nitrogen injection main pipe d, and the lower end face is close to the filter element port, and the high-temperature nitrogen injection main pipe d extends to the outside of the shell and is provided with a high-temperature nitrogen pulse valve c; a fixed catalyst bed b is provided above the high-temperature nitrogen injection main pipe d, and is connected to the catalyst bed fixing structure b3 by bolts, and the catalyst bed fixed structure b4 is provided with a high-temperature nitrogen pulse valve c; a fixed catalyst bed b is provided above the high-temperature nitrogen injection main pipe d, and is connected to the catalyst bed fixed structure b3 by bolts, and the catalyst bed fixed structure b3 ... The fixed structure b3 is fixed to the inner wall of the shell a by welding, and the fixed catalyst bed b includes a catalyst bed plate b1, a catalyst bed baffle b2, and a catalyst bed fixed structure b3; the regulating valve g and the flow meter h are respectively arranged on the oxygen (air) and normal temperature nitrogen pipelines, the regulating valve g includes an oxygen or air regulating valve g1 and a normal temperature nitrogen regulating valve g2, and the flow meter h includes an oxygen or air flow meter h1 and a normal temperature nitrogen flow meter h2; the lower part of the device is provided with a pre-filtration cavity pressure monitor i1 and a cavity temperature monitor i2, the surface of the filter element is provided with a filter element temperature monitor i3 by angle iron welding, and the top of the device is provided with a post-filtration cavity pressure monitor i4 and a cavity outlet oxygen content monitor i5; the middle shell opening of the device is provided with a filter element inspection hole j, and the upper part of the shell is provided with a quick-release flange head k;

[0065] Among them, the high-temperature pyrolysis oil and gas of unpurified waste plastics generated from the upstream process enters the device from the bottom. When the pyrolysis oil and gas pass through the filter element f, the dust in the pyrolysis oil and gas will be filtered and captured, and the captured ash is discharged from the bottom outlet of the device. The filtered pyrolysis oil and gas enter the fixed catalyst bed b at the top of the device. The fixed catalyst bed b is filled with a catalyst. The pyrolysis oil and gas are catalytically upgraded in the fixed catalyst bed b, and then the oil and gas are discharged from the top outlet of the device to enter the downstream process flow. The gas outlet is not limited to the top of the device, and a suitable position can be selected according to actual needs, such as it can also be set at the upper right part of the dust collector;

[0066] Among them, the unpurified waste plastic high-temperature pyrolysis oil and gas enters the inner cavity of the device and passes through the filter element f, such as Figure 3As shown, the filter element f includes a sintered catalyst coating f1, a filter element frame f2, and a filter element fixing bolt f3. The thickness of the sintered catalyst coating f1 is 0.5 to 2 mm, and the aperture of the perforated metal film outside the filter element frame is 5 to 20 μm. The dust in the high-temperature pyrolysis oil and gas is intercepted by physical filtration, and the dust removal efficiency is ≥ 99%. At the same time, the high-temperature pyrolysis oil and gas undergo a catalytic reaction in the sintered catalyst coating f1 on the inner layer of the filter element, thereby achieving catalytic quality improvement of the pyrolysis oil and gas. The filter element f is fixed to the filter element fixing plate f4 by a bolt structure, and the filter element fixing plate f4 is welded to the inner wall of the housing a.

[0067] Among them, the types of catalysts sprayed on the sintered catalyst coating f1 can be metal oxides (nano-alumina, NiO, CaO, etc.), molecular sieve catalysts (HY type molecular sieve, ZSM-5, etc.), precious metal component catalysts, etc. The catalyst type can be screened and determined according to the different components and target products of the oil and gas from the high-temperature pyrolysis of waste plastics;

[0068] In addition, during normal operation, high-temperature pyrolysis oil and gas flows from the outside of the filter element to the inside of the filter element, and during injection, high-temperature nitrogen flows from the inside of the filter element to the outside of the filter element; after a period of operation, a layer of filter cake structure will form on the outside of the filter element f. If it is not treated, it will increase the filtration pressure drop of the device, which will affect the filtration effect and the normal operation of the equipment; the device sets the post-filtration cavity pressure monitoring i4 and the pre-filtration cavity pressure monitoring i1 on the inside and outside of the filter element f respectively. When the pressure monitoring difference between the inside and outside reaches the preset value, the high-temperature nitrogen injection system is started, and the pressure difference is 500~3000Pa;

[0069] Among them, the high-temperature nitrogen injection system includes a high-temperature nitrogen injection main pipe d, a high-temperature nitrogen back-blowing structure e and a high-temperature nitrogen pulse valve c. The device sets the number of high-temperature nitrogen pulse valves c according to the number of filter elements f, and the number of filter elements corresponding to each pulse valve can be adjusted according to actual working conditions; there are two ways to start the high-temperature nitrogen injection system: one is to start after the pressure monitoring difference between the inside and the outside reaches a preset value, and the pressure difference is 500-3000Pa; the other is to start at a fixed time interval, and the time interval is generally 10-30 minutes; when the starting conditions are met, pressurized high-temperature nitrogen (0.3-0.5MPa.G) enters the high-temperature nitrogen back-blowing structure e through the high-temperature nitrogen pulse valve c, and the opening and closing time of the high-temperature nitrogen pulse valve c is 1-5 seconds. The pressurized high-temperature nitrogen fills the internal space of the filter element in a short time, so that the filter element is full of pressure and shakes, and the filter cake structure formed on the outside of the filter element is backblown and dropped, and the dropped ash is accumulated at the bottom of the dust collector device and discharged;

[0070] In addition, if Figure 4As shown, the extra space at the top of the device is used to set up a fixed catalyst bed b, and the pyrolysis oil and gas passing through the filter element f enters the fixed catalyst bed b at the top of the device. The pyrolysis oil and gas undergo a catalytic reaction on the bed, and the pyrolysis oil and gas after the reaction are discharged from the top outlet of the device and enter the downstream process flow;

[0071] Among them, the fixed catalyst bed b is composed of a catalyst bed flower plate b1, a catalyst bed baffle b2, and a catalyst bed fixed structure b3; the catalyst bed flower plate b1 is provided with small holes with a diameter of ≤10mm, which allow the pyrolysis oil and gas to pass through while preventing the catalyst from falling. The catalyst is generally a shaped porous solid particle with a certain physical strength, and the particle size is 10-50mm; a catalyst bed baffle b2 is arranged in the bed for partitioning and fixing the catalyst, and the number of catalyst bed baffles b2 should not be too many, generally 3-8 pieces; a fixed catalyst bed fixed structure b3 is arranged along the inner wall of the device on both sides of the upper and lower sides of the catalyst bed for fixing and disassembling the catalyst bed; the connection form of the catalyst bed fixed structure b3 and the catalyst bed and the device shell is detachable, which is convenient for the installation and maintenance of the catalyst bed; the pyrolysis oil and gas passing through the filter element f enters the fixed catalyst bed b at the top of the device, and the pyrolysis oil and gas undergo a catalytic reaction on the bed. The pyrolysis oil and gas after the reaction are discharged from the top outlet of the device and enter the downstream process flow;

[0072] In order to ensure and control the temperature of the device, a heating source and a heat insulation layer are arranged on the outer wall of the device shell a. The heating source can be electric heating, high-temperature flue gas or heat transfer oil. The high-temperature flue gas and heat transfer oil are realized by winding a coil around the outer wall, and the electric heating is realized by winding an electric heating wire around the outer wall.

[0073] The device has a catalyst regeneration function. The catalyst regeneration process is that oxygen and carbon deposits in the catalyst gaps are burned under high temperature conditions, thereby realizing catalyst regeneration by high-temperature charring. The charring temperature is 400-600°C. The system monitors the oxygen and nitrogen consumption through the oxygen or air flow meter h1 and the normal temperature nitrogen flow meter h2 respectively, and controls the oxygen and nitrogen flow rates through the oxygen or air regulating valve g1 and the normal temperature nitrogen regulating valve g2 respectively, thereby realizing the control of the oxygen content at the outlet of the device. The nitrogen purity is ≥99.99%. The reason why the nitrogen is at normal temperature is to prevent overheating during the charring process, thereby affecting the operation and safety of the device.

[0074] Furthermore, the connecting pipeline between the high-temperature dust collector 3 and the oil-gas separation and purification system 4 should avoid horizontal straight pipe sections. Specifically, a large-angle inclined pipe can be used to shorten the pipeline length as much as possible and reduce dust accumulation and blockage in the pipeline.

[0075] 3. Oil and gas separation and purification system

[0076] The high-temperature mixed oil and gas after dust removal and catalytic quality improvement are discharged from the high-temperature dust collector 3 and enter the oil and gas separation purification system 4 for oil and gas separation. The oil and gas separation purification system of the present invention has the function of switching between oil washing and water washing. The oil and gas separation purification system adopts a direct spray cooling method to condense the high-temperature oil and gas and complete the separation of the gas-liquid two phases. The spray coolant can be water or oil.

[0077] 1. Oil washing cooling process

[0078] Specifically, when the pyrolysis raw material has fewer impurities and a higher oil yield, the oil-gas separation and purification system adopts an oil-washing cooling process, and the primary oil-gas separation tower 41, the secondary oil-gas separation tower 42, and the tertiary oil-gas separation tower 43 are put into use. The primary oil-gas separation tower 41 can use oil as a spray liquid. After the spray liquid exchanges heat with the high-temperature mixed oil and gas, the pyrolysis oil is condensed and precipitated to become part of the spray liquid. The heated spray liquid is cooled by the primary heat exchanger E1 to restore the refrigerant function and form a cycle. By controlling the flow rate and temperature of the spray liquid, the gas phase temperature at the outlet above the primary oil-gas separation tower 41 is controlled to be higher than the dew point temperature of water, so that the pyrolysis oil is condensed and precipitated in the primary oil-gas separation tower 41 and the water vapor is kept from condensing and precipitating. The pyrolysis oil collected in the primary oil-gas separation tower 41 is regularly discharged and collected according to the liquid level height of the primary oil-gas separation tower 41.

[0079] The mixed gas after the pyrolysis oil is removed enters the secondary oil-gas separation tower 42 and the tertiary oil-gas separation tower 43 in sequence, the purpose of which is to condense the water vapor in the mixed gas, remove the water in the mixed gas, and remove the chloride in the pyrolysis gas to complete the purification of the pyrolysis gas. The secondary oil-gas separation tower 42 and the tertiary oil-gas separation tower 43 both use water as the spray liquid to fully condense the residual water vapor therein. The dehydrated non-condensable gas enters the solid heat carrier furnace 5 and is burned as fuel to provide heat for the system.

[0080] Specifically, Figure 5As shown, the oil washing cooling process is adopted, the bottom valve F1 of the primary oil and gas separation tower is closed, the primary circulation pump P1, the primary circulation pump inlet valve F2, and the primary circulation pump outlet valve F3 are opened, and diesel, white oil, washing oil, etc. can be used as the start-up spray liquid. After the spray liquid exchanges heat with the high-temperature mixed oil and gas, the pyrolysis oil is condensed, precipitated, and settled into the bottom of the primary oil and gas separation tower 41 to become part of the spray liquid. The spray liquid is discharged from the lower right outlet of the primary oil and gas separation tower 41 and pumped into the primary heat exchanger E1 through the primary circulation pump P1, so that the spray liquid is cooled and restored to the refrigerant function. The spray liquid discharged from the outlet of the primary heat exchanger E1 is sprayed into the primary oil and gas separation tower 41 to exchange heat with the high-temperature mixed oil and gas to form a cycle. By controlling the flow rate and temperature of the spray liquid, the gas phase temperature at the upper outlet of the primary oil and gas separation tower 41 is controlled to be higher than the dew point temperature of water, so that the pyrolysis oil is condensed and settled in the primary oil and gas separation tower 41 and the water vapor is kept from condensing and precipitating. The pyrolysis oil collected in the primary oil-gas separation tower 41 is discharged and collected regularly according to the liquid level height of the primary oil-gas separation tower 41. In actual operation, in order to achieve the heat exchange effect and prevent the oil pipeline from being blocked, the spray liquid temperature of the primary oil-gas separation tower 41 is controlled at 65-75°C, and the tower bottom temperature of the primary oil-gas separation tower 41 can be controlled at 100-105°C.

[0081] The mixed gas without pyrolysis oil enters the secondary oil and gas separation tower 42, and is sprayed and cooled for the second time in the secondary oil and gas separation tower 42. The secondary oil and gas separation tower 42 uses water as the circulating spray liquid. The purpose of the secondary oil and gas separation tower 42 is to condense and precipitate the water vapor in the mixed gas and remove the moisture in the mixed gas. When the mixed gas enters the secondary oil and gas separation tower 42, it directly contacts and exchanges heat with the spray liquid (water), so that the gas phase is cooled and the water vapor is cooled, precipitated and settled, and falls into the tower kettle of the secondary oil and gas separation tower 42, and then discharged from the liquid phase outlet at the lower right of the secondary oil and gas separation tower 42 and sent to the secondary heat exchanger E2 through the secondary circulation pump P2 to complete the cooling of the spray liquid. The cooled spray liquid leaves the secondary heat exchanger E2 and is sprayed into the secondary oil and gas separation tower 42 again to complete the cycle. In actual operation, the spray liquid temperature of the secondary oil and gas separation tower 42 is controlled at 50-55°C.

[0082] The gas discharged from the secondary oil-gas separation tower 42 enters the tertiary oil-gas separation tower 43, and is subjected to three-stage spray cooling using low-temperature water to supercool the pyrolysis gas and fully condense the residual water vapor therein. The dehydrated non-condensable gas enters the solid heat carrier furnace 5 and is burned as fuel to provide heat for the system. In actual operation, the spray liquid temperature of the tertiary oil-gas separation tower 43 is controlled at 5-15°C, and the temperature of the non-condensable gas discharged from the tertiary oil-gas separation tower 43 is controlled at 20-23°C.

[0083] 2. Water washing and cooling process

[0084] When the oil-gas separation and purification system adopts the water-washing and cooling process, the primary oil-water separator 44 and the secondary oil-water separator 45 are put into use. When the water-washing and cooling process is adopted, the primary oil-gas separation tower 41 uses water as the spray liquid, and the spray liquid directly contacts and exchanges heat with the high-temperature mixed oil and gas, so that the pyrolysis oil and water vapor in the mixed gas are condensed and settled. The cooled liquid and the spray liquid flow from the bottom pipeline of the primary oil-gas separation tower 41 to the primary oil-water separator 44 and the secondary oil-water separator 45 in sequence. In the two-stage oil-water separator, the pyrolysis oil and the spray water are separated, and the separated pyrolysis oil is output as a product for sale. The separated spray water is cooled by the primary heat exchanger E1 and continues to be circulated as a cooling medium to form a spray liquid cycle. The gas discharged from the top of the primary oil-gas separation tower 41 enters the secondary oil-gas separation tower 42 and the tertiary oil-gas separation tower 43 in sequence to further remove the residual pyrolysis oil and water to obtain clean pyrolysis gas. The working mode of the secondary oil-gas separation tower 42 and the tertiary oil-gas separation tower 43 is the same as that when the oil washing spray process is adopted.

[0085] Specific as Figure 5 As shown, during the water washing and cooling process, the primary circulation pump P1, the primary circulation pump inlet valve F2, and the primary circulation pump outlet valve F3 are closed, and the primary oil and gas separation tower bottom valve F1, the water washing circulation pump P4, the water washing circulation pump inlet valve F4, and the water washing circulation pump outlet valve F5 are opened. When the water washing and cooling process is adopted, produced water is used as the spray liquid, and the spray liquid is sprayed into the tower through the nozzle, and heat is exchanged with the high-temperature mixed oil and gas, so that the pyrolysis oil and water vapor in the mixed gas are condensed and settled. The cooled liquid and the spray liquid flow from the bottom pipeline of the primary oil and gas separation tower 41 to the primary oil-water separator 44 and the secondary oil-water separator 45 in sequence. In the two-stage oil-water separator, the pyrolysis oil and the spray water are separated, and the separated pyrolysis oil is output as a product for sale. The separated spray water is cooled by the primary heat exchanger E1 and continues to be circulated as a cooling medium to form a spray liquid cycle. The gas discharged from the top of the first oil-gas separation tower 41 enters the second oil-gas separation tower 42 and the third oil-gas separation tower 43 in sequence, and further removes the residual pyrolysis oil and water to obtain clean pyrolysis gas. The working mode of the second oil-gas separation tower 42 and the third oil-gas separation tower 43 is the same as that of the oil washing spray process.

[0086] In actual operation, the first-stage oil-gas separation tower 41, the second-stage oil-gas separation tower 42, and the third-stage oil-gas separation tower 43 can be arranged with multiple layers of nozzles according to actual needs to meet the spraying effect.

[0087] The oil-gas separation and purification system has three major functions: gas-liquid separation, oil-water separation, and non-condensable gas purification. Furthermore, in actual operation, the oil-gas separation tower is not limited to a 3-stage setting scheme, and a 2-4-stage spray tower can be used according to actual needs and spray effects; the oil-water separator is not limited to a 2-stage, and a 1-3-stage oil-water separator can be used according to actual needs and separation effects.

[0088] The clean non-condensable gas discharged from the three-stage oil-gas separation tower 43 has a high calorific value and is sent to the solid heat carrier furnace 5 to be burned as fuel to provide energy for the system. When the system raw material uses waste plastics, the non-condensable gas output can generally maintain the energy balance of the system, and no additional supplementary fuel is required. At the same time, the solid heat carrier furnace 5 is provided with a supplementary gas pipeline. When the properties of the raw materials change, such as the water content is too high or the calorific value is too low, the non-condensable gas is not enough to maintain the energy balance of the system. At this time, the supplementary gas pipeline can be opened to supplement the energy of the system. In specific operations, natural gas can be used as a supplementary fuel.

[0089] The pyrolysis oil collected in the present invention has a high calorific value and is mainly composed of light components. It can be directly sold as a product, or it can enter the oil refining process to carry out deep processing of the oil and produce a variety of chemical products to increase added value.

[0090] In addition to being applicable to the pyrolysis of waste plastics to produce oil, the present invention can also be used for the resource utilization of organic solid wastes such as waste tires, biomass, oily sludge, and stale garbage.

[0091] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

[0092] Parts not described in detail in the present invention belong to common knowledge of those skilled in the art.

Claims

1. A waste plastic pyrolysis oil production system, characterized by: It includes solid heat carrier circulation heating system, oil and gas separation and purification system, bipolar dust removal and catalytic body integrated system; The solid heat carrier circulation heating system includes a pyrolysis reactor, a solid heat carrier furnace, a gas-solid separator, a flow distributor, a return feeder, and a bottom combustion organization module; the bipolar dust removal and catalytic body integrated system includes a spiral dust collector and a dust collector; The solid heat carrier furnace heats the solid heat carrier in the furnace and promotes the combustion of pyrolytic carbon under the action of the bottom combustion organization module. The high-temperature flue gas carries the high-temperature solid heat carrier into the gas-solid separator. In the gas-solid separator, the solid heat carrier and the high-temperature flue gas are separated. The separated flue gas is discharged from the outlet of the gas-solid separator and enters the subsequent flue gas purification process. The solid heat carrier enters the flow distributor from the lower outlet of the gas-solid separator. The flow distributor controls the flow of solid heat carrier entering the pyrolysis reactor and returning to the solid heat carrier furnace according to the feed amount and the final pyrolysis temperature; Waste plastics and the solid heat carrier from the flow distributor enter the pyrolysis reactor at the same time. The waste plastics are heated and pyrolyzed in the pyrolysis reactor, and converted into pyrolysis oil, pyrolysis gas, and pyrolysis carbon; the pyrolysis carbon and the cooled solid heat carrier enter the return feeder from the lower outlet of the pyrolysis reactor together, and enter the solid heat carrier furnace through the outlet of the return feeder; the mixed oil and gas in the pyrolysis reactor first enter the spiral ash cleaner, and then enter the dust collector through the spiral ash cleaner. The two-stage dust removal combination completes the dust removal of the high-temperature mixed oil and gas; the dust collector inputs the dust-removed oil and gas into the oil and gas separation and purification system to complete the oil and gas separation, and the separated non-condensable gas enters the solid heat carrier furnace as fuel for combustion.

2. A waste plastic pyrolysis oil production system according to claim 1, characterized in that: The flow distributor contains three interconnected cavities: a fluidizing chamber, a pyrolysis chamber, and a bypass chamber. The heat carrier enters the fluidizing chamber from the heat carrier inlet, and enters two logistics outlet channels respectively through the pyrolysis chamber and the bypass chamber. The two logistics outlet channels are a heat carrier outlet pyrolysis path and a heat carrier outlet bypass path. The heat carrier outlet pyrolysis path delivers the solid heat carrier into the pyrolysis reactor, and the heat carrier outlet bypass path delivers the solid heat carrier into the solid heat carrier furnace. The heat carrier outlet pyrolysis path is provided with a pyrolysis path high-temperature plug-in valve, and the heat carrier outlet bypass path is provided with a bypass path high-temperature plug-in valve.

3. A waste plastic pyrolysis oil production system according to claim 2, characterized in that: The flow distributor is provided with a bypass channel loosening air inlet, a pyrolysis channel loosening air inlet and a fluidizing air inlet at the bottom; the bypass loosening air is blown into the bypass cavity through the bypass channel loosening air inlet, and then the heat carrier is blown to the heat carrier outlet bypass channel; the pyrolysis channel loosening air is blown into the pyrolysis cavity from the pyrolysis channel loosening air inlet, and then the heat carrier is blown to the heat carrier outlet pyrolysis path; the fluidizing air enters the fluidizing cavity from the fluidizing air inlet to maintain the fluid state of the bed in the fluidizing cavity; according to the feed amount and the final pyrolysis temperature, the opening of the pyrolysis channel high-temperature gate valve and the bypass channel high-temperature gate valve is adjusted, and the loosening air and fluidizing air flow rates are adjusted in coordination, thereby controlling the flow rate of the high-temperature solid heat carrier entering the pyrolysis reactor, controlling the heat entering the pyrolysis reactor, and realizing controllable regulation of the pyrolysis reaction.

4. A waste plastic pyrolysis oil production system according to claim 1, characterized in that: The bottom combustion organization module includes a gas pipeline, a gas hood, a combustion-supporting air pipeline, a combustion-supporting air hood and a bottom ignition burner; When starting the furnace, turn on the bottom ignition burner. When the pyrolysis system is fed and the output is running stably, turn off the bottom ignition burner and enable the gas pipeline. The gas is sprayed directly into the dense phase area of ​​the furnace through the gas pipeline through the gas wind cap, and the combustion-supporting air is blown into the furnace through the combustion-supporting air pipeline through the combustion-supporting air hood. The gas and the combustion-supporting air meet in the dense phase area and burn under the high temperature environment of the dense phase area.

5. The waste plastic pyrolysis oil production system according to claim 1, characterized in that: The oil-gas separation and purification system has both water washing and oil washing spray cooling functions; when the system is put into operation after materials are put into operation, oil washing spray cooling is first used. If the gas phase outlet temperature of the first-level oil-gas separation tower rises above the set threshold or the spray circulation flow through the first-level circulation pump decreases, it is switched to water washing, otherwise oil washing is continued.

6. A waste plastic pyrolysis oil production system according to claim 5, characterized in that: The oil-gas separation and purification system comprises a primary oil-gas separation tower, a secondary oil-gas separation tower, a tertiary oil-gas separation tower, a primary oil-water separator, and a secondary oil-water separator; In the oil washing spray cooling, the primary oil and gas separation tower, the secondary oil and gas separation tower, and the tertiary oil and gas separation tower are put into use; the outlet gas temperature above the primary oil and gas separation tower is controlled to be higher than the dew point temperature of water, so that the pyrolysis oil is condensed and settled in the primary oil and gas separation tower and the water vapor is kept from condensing and precipitating; the mixed gas without the pyrolysis oil enters the secondary oil and gas separation tower and the tertiary oil and gas separation tower in turn, so as to condense and precipitate the water vapor in the mixed gas, remove the moisture in the mixed gas, and remove the chloride in the pyrolysis gas, so as to complete the purification of the pyrolysis gas; In the water-washing spray cooling, the first-stage oil-gas separation tower uses water as the spray liquid. The spray liquid directly contacts and exchanges heat with the high-temperature mixed oil and gas, so that the pyrolysis oil and water vapor in the mixed gas condense and settle. The cooled liquid and the spray liquid flow from the first-stage oil-gas separation tower to the first-stage oil-water separator and the second-stage oil-water separator in sequence. In the two-stage oil-water separator, the pyrolysis oil and the spray water are separated. The separated spray water is cooled by the first-stage heat exchanger and then continues to be circulated as a cooling medium to form a spray liquid cycle; the gas discharged from the top of the first-stage oil-gas separation tower enters the second-stage oil-gas separation tower and the third-stage oil-gas separation tower in sequence to further remove the residual pyrolysis oil and water to obtain clean pyrolysis gas; In both methods, water is used as the spraying liquid in the secondary oil-gas separation tower and the tertiary oil-gas separation tower to fully condense the residual water vapor therein, and the dehydrated non-condensable gas enters the solid heat carrier furnace and is burned as fuel.

7. A waste plastic pyrolysis oil production system according to claim 6, characterized in that: The spray liquid temperature of the first-stage oil and gas separation tower is controlled at 65-75°C, the bottom temperature of the first-stage oil and gas separation tower can be controlled at 100-105°C, the spray liquid temperature of the second-stage oil and gas separation tower is controlled at 50-55°C, the spray liquid temperature of the tertiary oil and gas separation tower is controlled at 5-15°C, and the temperature of the non-condensable gas discharged from the tertiary oil and gas separation tower is controlled at 20-23°C.

8. The waste plastic pyrolysis oil production system according to claim 1, characterized in that: The dust collector includes a shell, a fixed catalyst bed, a filter element, and a nitrogen injection system; The nitrogen blowing system includes a nitrogen blowing main pipe, a nitrogen backflush structure, and a nitrogen supply unit outside the housing, which is used to backflush the filter cake structure formed on the outside of the filter element and discharge it from the bottom outlet of the housing; The filter element is installed inside the housing, dividing the inner cavity of the housing into a pre-filter cavity and a post-filter cavity; a nitrogen backflush structure is installed on a nitrogen injection main pipe inside the housing to inject nitrogen from the filter element port of the filter element into the interior of the filter element; a fixed catalyst bed is installed in the post-filter cavity; the fixed catalyst bed is filled with a catalyst; The high-temperature pyrolysis oil and gas from unpurified waste plastics enters from the bottom of the shell, and the dust in the pyrolysis oil and gas is filtered and captured by the filter element and discharged from the bottom outlet of the shell. The filtered pyrolysis oil and gas enter the fixed catalyst bed, where the pyrolysis oil and gas react with the catalyst to achieve catalytic quality improvement of the oil and gas, and then the oil and gas are discharged from the top outlet of the shell.

9. A waste plastic pyrolysis oil production system according to claim 8, characterized in that: The fixed catalyst bed is composed of a catalyst bed flower plate, a catalyst bed baffle, and a catalyst bed fixing structure; the catalyst bed flower plate is provided with small holes, the size of which allows pyrolysis oil and gas to pass through while preventing the catalyst from falling; a catalyst bed baffle is arranged in the bed for partitioning and fixing the catalyst; a fixed catalyst bed fixing structure is arranged along the inner wall of the device on the upper and lower sides of the catalyst bed for fixing and disassembling the catalyst bed; the diameter of the small hole is ≤10mm, the catalyst is a shaped porous solid particle with a certain physical strength, and the particle size is 10 to 50mm.

10. A waste plastic pyrolysis oil production system according to claim 8, characterized in that: The dust collector also includes a charring system; the charring system burns the carbon deposits in the catalyst gaps by introducing oxygen into the shell, thereby achieving catalyst regeneration by high-temperature charring; The charring system includes an oxygen or air flow meter and a normal temperature nitrogen flow meter, an oxygen or air regulating valve and a normal temperature nitrogen regulating valve, a cavity temperature monitoring and a filter element temperature monitoring, a cavity pressure monitoring before filtration, a cavity pressure monitoring after filtration and a cavity outlet oxygen content monitoring; The oxygen or air flow meter and the normal temperature nitrogen flow meter are used to monitor the amount of oxygen and nitrogen introduced into the shell, respectively, and the oxygen or air regulating valve and the normal temperature nitrogen regulating valve are used to control the oxygen and nitrogen flow rates, respectively, so as to control the oxygen content at the shell outlet; The oxygen content monitoring at the cavity outlet is used to monitor the changes in oxygen content in the shell during catalyst regeneration; the cavity pressure monitoring before filtration and the cavity pressure monitoring after filtration are used to monitor the pressure changes during catalyst regeneration; cavity temperature monitoring and filter element temperature monitoring are provided to monitor the temperature changes during catalyst regeneration. When the pressure change / temperature change exceeds the preset range, room temperature nitrogen is introduced into the shell; the high pressure alarm value is 15~20kPa.G, and the low pressure alarm value is -10~5kPa.G; the charring temperature is 400~600℃; the oxygen content during the charring process does not exceed 1%.

11. A waste plastic pyrolysis oil production system according to claim 8, characterized in that: The starting methods of the nitrogen blowing system include: one is to start after the pressure difference between the pre-filter cavity and the post-filter cavity reaches a preset value, and the other is to start after setting a fixed time interval; when the starting conditions are met, the high-pressure nitrogen fills the internal space of the filter element in a short time, so that the filter element is filled with pressure and shakes, and the filter cake structure formed on the outside of the filter element is blown back and dropped; the preset value ranges from 500 to 3000 Pa; the time interval is generally 10 to 30 minutes; the pressure of the high-pressure nitrogen is 0.3-0.5MPa.G; the short time is 1 to 5 seconds.

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