A processing method and system for fluidized cracking of waste plastics

Abstract

The present disclosure relates to a method and system for fluidized cracking of waste plastics. The method comprises the following steps: S1. Passing the waste plastics to be processed into a waste plastic liquefaction unit for liquefaction to produce liquefied waste plastics; S2. Passing the liquefied waste plastics into a waste plastic viscosity reduction unit for visbreaking to produce visbroken liquefied waste plastic oil and a first dry gas; S3. Passing the visbroken liquefied waste plastic oil into a contact cracking reaction unit for contact with a fluidized contact agent to undergo a cracking reaction, producing reaction oil and gas and regenerated contact agent; S4. Passing the reaction oil and gas into a separation unit for separation to produce a second dry gas, liquefied gas, a gasoline fraction, a diesel fraction, and a wax oil fraction. This disclosure achieves resource utilization of waste plastics.

Description

Technical Field

[0001] The present disclosure relates to the field of waste plastic resource recycling, and in particular to a processing method and a processing system for fluidized cracking of waste plastic. Background Art

[0002] With the advancement of science and technology and industrial development, plastics are now widely used as packaging materials in our daily lives. However, used plastic waste cannot decompose naturally, and only a few types of waste plastic can be reprocessed and reused through specific recycling channels. A large amount of waste plastic ends up in landfills as household waste. Because waste plastics are difficult to decompose, they occupy a significant amount of space. The rapid increase in waste plastic generation in recent years has made the rapid and environmentally friendly recycling of waste plastics an urgent task.

[0003] The simplest way to dispose of waste plastics is direct incineration, but this produces toxic gases harmful to humans and causes secondary environmental pollution. Waste plastic pyrolysis technology involves cracking waste plastics in the absence or absence of oxygen by heating or in the presence of a catalyst, breaking down high polymers into low-molecular-weight substances. These products produce gasoline, kerosene, diesel fractions, and some pyrolysis gases. This technology alleviates the pollution caused by waste plastics while enabling their recycling, making it a key area of waste plastic resource recovery.

[0004] At present, waste plastic cracking and recovery technologies mainly include waste plastic pyrolysis and catalytic pyrolysis technologies. CN107746722A discloses a method and equipment for preparing gasoline and diesel by cracking waste plastics. The system dissolves the crushed and impurity-removed waste plastics in liquid pyrolysis oil, and performs melting, dehydration, dechlorination, cracking and quality improvement through precise temperature control. The process requires a large amount of solvent oil. For example, CN101374930A discloses a method and device for contact decomposition of waste plastics, which belongs to catalytic pyrolysis technology. A heated and stirred rotary kiln is used as a reactor, an FCC catalyst is used as a heat medium and a catalytic center, and an appropriate amount of Ca and Fe compounds are added to decompose the waste plastics. However, after the device has been operated for a period of time, the contact agent in the reactor needs to be taken out and regenerated. More waste plastic cracking technologies use intermittent pyrolysis reactors. This type of method has the problem of small processing scale, and impurities in the product cannot be removed. Summary of the Invention

[0005] The purpose of the present disclosure is to provide a processing method and processing system for fluidized cracking of waste plastics, which can continuously perform fluidized cracking on waste materials, realize the effective utilization of waste plastic resources, and effectively remove impurities in the products.

[0006] In order to achieve the above objectives, the present disclosure provides a first aspect of a method for processing waste plastics by fluidized cracking, the method comprising the following steps:

[0007] S1, allowing the waste plastic to be processed to enter the waste plastic liquefaction unit for liquefaction treatment to obtain liquefied waste plastic;

[0008] S2, allowing the liquefied waste plastic to enter a waste plastic viscosity reduction unit for visbreaking treatment to obtain visbreaking liquefied waste plastic oil and a first dry gas;

[0009] S3, allowing the visbroken liquefied waste plastic oil to enter a contact cracking reaction unit, where it contacts a fluidized contact agent to undergo a cracking reaction, thereby obtaining reaction oil gas and a regenerated contact agent;

[0010] S4, allowing the reaction oil and gas to enter a separation unit for separation treatment to obtain a second dry gas, liquefied gas, a gasoline fraction, a diesel fraction, and a wax oil fraction;

[0011] The regenerated contact agent is allowed to enter the regeneration unit and is regenerated in the presence of oxygen to obtain regenerated contact agent and regenerated flue gas; the regenerated contact agent is returned to the contact cracking reaction unit for continued use.

[0012] Optionally, before step S1, the method further includes: allowing the chlorine-containing waste plastic raw material to enter the waste plastic hot melt dehydration and dechlorination unit, and melting and dehydrating the chlorine-containing waste plastic raw material under a first temperature condition to obtain dehydrated waste plastic; then heating the dehydrated waste plastic to a second temperature for dechlorination treatment to obtain dehydrated and dechlorinated waste plastic and hydrogen chloride-containing gas; allowing the dehydrated and dechlorinated waste plastic to be cooled and crushed in a cooling and crushing unit in sequence to obtain dehydrated and dechlorinated waste plastic particles; allowing the dehydrated and dechlorinated waste plastic particles to enter the waste plastic liquefaction unit; or allowing the dehydrated and dechlorinated waste plastic to directly enter the waste plastic liquefaction unit.

[0013] Optionally, the method further comprises: allowing the hydrogen chloride-containing gas to enter a hydrogen chloride absorption unit and contact the hydrogen chloride absorbent to perform hydrogen chloride absorption treatment; optionally, allowing the hydrogen chloride-containing gas to enter the hydrogen chloride absorption unit under the action of a vacuum system; wherein the hydrogen chloride absorbent is water or an alkaline solution with a pH greater than 7; optionally, the alkaline solution comprises one or more of sodium hydroxide solution, potassium hydroxide solution, calcium hydroxide solution, sodium bicarbonate solution, sodium carbonate solution and ammonia water.

[0014] Optionally, the contact cracking reaction unit in step S3 performs a cracking reaction and also obtains ash with carbon; the method further includes: allowing the ash with carbon and the contact agent to be regenerated to enter a regeneration unit, and in the presence of oxygen, causing the contact agent to be regenerated and the char on the ash with carbon to undergo a complete combustion reaction to obtain regenerated flue gas and regenerated contact agent; preferably, the method further includes: allowing at least a portion of the first dry gas and / or at least a portion of the second dry gas to enter the regeneration unit, and causing the contact agent to be regenerated and the ash with carbon to undergo a complete combustion reaction in the presence of oxygen and dry gas to obtain regenerated flue gas and regenerated contact agent; preferably, based on the total weight of the contact agent to be regenerated, the carbon content of the contact agent to be regenerated is 0.5 to 5.0 weight %.

[0015] Optionally, in step S1, the waste plastic liquefaction unit adopts a heating liquefaction conveying device to perform the liquefaction treatment; optionally, the heating liquefaction conveying equipment includes a first screw-type heating conveying device; preferably, the first screw-type heating conveying device is selected from a twin-screw or single-screw heating conveying device with heating; preferably, the process conditions of the liquefaction treatment include: an outlet temperature of 380 to 500°C, preferably 400 to 450°C; a residence time of 5 to 30 minutes, preferably 5 to 15 minutes.

[0016] Optionally, in step S2, the waste plastic viscosity reduction unit adopts a viscosity reduction reactor to perform the viscosity reduction and cracking treatment; preferably, the viscosity reduction reactor is an adiabatic viscosity reduction reactor; preferably, the process conditions of the visbreaking treatment include: a reaction temperature of 380 to 500°C, more preferably 390 to 420°C; a residence time of 10 to 90 min, preferably 20 to 70 min, more preferably 30 to 70 min.

[0017] Optionally, in step S3, the process conditions of the cracking reaction include: a reaction temperature of 490-750°C, a weight hourly space velocity of 1-100h -1 The mass ratio of the contact agent to the waste plastic to be treated is 5 to 30:1; preferably, the reaction temperature is 500 to 650 ° C, and the weight hourly space velocity is 3 to 60h -1 , the mass ratio of the contact agent to the waste plastic to be treated is 6 to 20:1; preferably, the visbroken liquefied waste plastic oil and steam are allowed to enter the contact cracking reaction unit; preferably, the mass ratio of steam to the waste plastic to be treated is 0.05 to 1:1, preferably 0.1 to 0.5:1.

[0018] Optionally, in step S3, the contact agent is one or more selected from silica-alumina material catalyst, quartz sand or coal coke powder; preferably, the particle size of the contact agent is 20 to 3000 μm; optionally, the silica-alumina material is selected from a catalyst containing molecular sieve and / or a catalyst not containing molecular sieve; preferably, the catalyst containing molecular sieve is selected from one or more molecular sieves selected from X molecular sieve, Y molecular sieve, mordenite, ZSM-5, pillared clay molecular sieve, SAPO, or a waste FCC catalyst; preferably, the catalyst not containing molecular sieve is selected from one or more of the first raw materials prepared as raw materials. Catalyst, the first raw material includes amorphous silica-alumina, clay, kaolin, montmorillonite, rectorite, illite, chlorite, pseudo-boehmite and silica; or the catalyst without molecular sieve is selected from a catalyst prepared with one or more of the second raw materials that have been acid-washed, calcined and sieved as raw materials, and the second raw material includes amorphous silica-alumina, clay, kaolin, montmorillonite, rectorite, illite and chlorite; or a catalyst prepared with one or more of the second raw materials that have been acid-washed, calcined and sieved and pseudo-boehmite and / or silica as raw materials; optionally, the coal coke powder is coal powder and / or petroleum coke powder.

[0019] Optionally, the regeneration treatment is carried out in a dense fluidized bed regenerator; preferably, the process conditions of the regeneration treatment include: an air residence time of 0.5 to 60 seconds, preferably 1.0 to 10 seconds, a gasification temperature of the dense bed of 600 to 750°C, preferably 600 to 700°C, an oxygen-containing gas volume of 10 to 50% by volume, and a linear velocity of the dense bed of 0.05 to 0.6 m / s, preferably 0.2 to 0.4 m / s.

[0020] Optionally, the hot melt dehydration and dechlorination unit of the waste plastic hot melt dehydration and dechlorination pulverization unit includes a second screw heating and conveying device and a vacuum device connected to the second screw heating and conveying device; preferably, the second screw heating and conveying device is selected from a twin-screw or single-screw conveying device; preferably, the process conditions of the melt dehydration treatment include: a first temperature of 100 to 170°C, preferably 120 to 150°C; a time of 0.05 to 1h, preferably 0.05 to 0.5h; a feed rate of chlorine-containing waste plastic raw materials of 5 to 5000kg / h, preferably 100 to 4000kg / h; preferably, the process conditions of the dechlorination treatment include: the second temperature is 150-370°C, preferably 220-350°C, and more preferably 300-330°C; the time is 0.05-0.5h, preferably 0.1-0.2h; the vacuum degree is 50-300mmHg, preferably 50-150mmHg; preferably, the heating rate from the first temperature to the second temperature is 50-200°C / min, preferably 50-150°C / min; optionally, the particle size of the dehydrated and dechlorinated waste plastic particles obtained by the pulverization treatment is 100-2000μm.

[0021] Optionally, the waste plastics to be processed include one or more of LDPE, HDPE, PS, PP, PET and PVC; optionally, the chlorine content in the waste plastics to be processed is less than 10 weight %; the ash content in the waste plastics to be processed is 1 to 40 weight %, preferably 3 to 20 weight %.

[0022] According to a second aspect of the present disclosure, a waste plastic fluidized cracking processing system is provided, which comprises: a waste plastic liquefaction unit, a waste plastic viscosity reduction unit, a contact cracking reaction unit, a separation unit and a regeneration unit; the waste plastic liquefaction unit comprises an inlet for waste plastic to be processed and an outlet for liquefied waste plastic, and the waste plastic liquefaction unit is configured to liquefy the waste plastic to be processed; the waste plastic viscosity reduction unit comprises an inlet for liquefied waste plastic, an outlet for liquefied waste plastic oil and a first dry gas outlet, and the waste plastic viscosity reduction unit is configured to perform viscosity reduction and cracking treatment on the liquefied waste plastic; the contact cracking reaction unit comprises an inlet for cracking raw materials, an inlet for contact agent, an outlet for reaction oil and gas and an outlet for contact agent to be regenerated; the inlet for cracking raw materials is connected to the outlet for liquefied waste plastic of the waste plastic viscosity reduction unit; The plastic oil outlet is connected, and the contact cracking reaction unit is configured to perform cracking reaction treatment on the liquefied waste plastic oil; the separation unit includes a separation inlet, a second dry gas inlet, a liquefied gas outlet, a gasoline fraction outlet, a diesel fraction outlet and a wax oil fraction outlet; the separation inlet is connected to the reaction oil and gas outlet of the contact cracking reaction unit, and the separation unit is configured to separate the reaction oil and gas; the regeneration unit includes an inlet for a regenerated contact agent, an inlet for an oxygen-containing gas, an outlet for a regenerated contact agent and an outlet for a regenerated flue gas; the regeneration unit is configured to regenerate the regenerated contact agent in the presence of oxygen to obtain a regenerated contact agent and a regenerated flue gas; the regenerated contact agent outlet is connected to the contact agent inlet of the contact cracking reaction unit.

[0023] Optionally, the processing system further comprises a waste plastic hot melt dehydration and dechlorination unit, a cooling and crushing unit and a hydrogen chloride absorption unit; the waste plastic hot melt dehydration and dechlorination unit comprises an inlet for chlorine-containing waste plastic raw materials, an outlet for dehydrated and dechlorinated waste plastics and an outlet for hydrogen chloride-containing gas; the waste plastic hot melt dehydration and dechlorination unit is configured to perform melting, dehydration and dechlorination treatments on the chlorine-containing waste plastics; the cooling and crushing unit is configured to perform cooling and crushing treatments on the dehydrated and dechlorinated waste plastics from the waste plastic hot melt dehydration and dechlorination unit; the hydrogen chloride absorption unit comprises an inlet for a gaseous material containing hydrogen chloride and a hydrogen chloride absorbent; the gaseous material containing hydrogen chloride inlet is connected to the hydrogen chloride-containing gas outlet of the waste plastic hot melt dehydration and dechlorination unit; preferably, the regeneration unit further comprises a dry gas inlet, the dry gas inlet It is connected to the first dry gas outlet of the waste plastic viscosity reduction unit and / or the second dry gas outlet of the separation unit; optionally, the connecting pipeline between the cracking raw material inlet of the contact cracking reaction unit and the liquefied waste plastic oil outlet of the waste plastic viscosity reduction unit also includes a steam inlet; preferably, the waste plastic liquefaction unit includes a heating liquefaction conveying device; optionally, the heating liquefaction conveying device includes a first screw heating conveying device; preferably, the first screw heating conveying device is selected from a twin-screw heating conveying device with heating; preferably, the waste plastic hot melt dehydration and dechlorination unit includes a second screw heating conveying device and a vacuum device connected to the second screw heating conveying device; preferably, the second screw heating conveying device is selected from a twin-screw conveying device.

[0024] Through the above technical solution, the present disclosure provides a processing method and processing system for fluidized cracking of waste plastics, which subject the waste plastic raw materials to liquefaction treatment and viscosity reduction cracking treatment, thereby enabling the waste plastics to be quickly liquefied and reduce the viscosity of the waste plastics; then, the waste plastics are contacted with a fluidized contact agent for cracking reaction, thereby enabling the waste plastics to be rapidly pyrolyzed in liquid form in contact with the high-temperature contact agent, thereby reducing the residence time of the products to obtain a more ideal product distribution, and removing heteroatoms from the waste plastics; through contact cracking to produce gaseous and liquid products, the waste plastics can be recycled as green resources, and the contact agent to be recycled after being regenerated; and the processing method can realize continuous waste plastic processing and improve processing efficiency; it has strong adaptability to waste plastic raw materials and does not require crushing and cleaning; waste plastics in landfills can be dehydrated, dechlorinated and reduced in situ, and subsequent cracking recovery can be processed centrally, which is easy to expand the production scale and reduce processing costs.

[0025] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0027] Figure 1 This is an exemplary flow chart of the processing method and processing system for fluidized cracking of waste plastics provided by our company.

[0028] Description of Reference Numerals

[0029] 1-waste plastic storage tank, 2-waste plastic hot melt dehydration, dechlorination and crushing total unit, 3-dehydration and dechlorination waste plastic particle storage tank, 4-waste plastic liquefaction unit, 5-waste plastic viscosity reduction unit, 6-contact cracking reaction unit, 7-regeneration unit, 8-separation unit, 9-hydrogen chloride absorption unit, 10-pipeline, 11-pipeline, 12-pipeline, 13-pipeline, 14-pipeline, 15-pipeline, 16-pipeline, 17-pipeline, 18-pipeline, 19-pipeline, 20-pipeline, 21-pipeline, 22-pipeline, 23-pipeline. DETAILED DESCRIPTION

[0030] The following describes the specific embodiments of the present disclosure in detail. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure.

[0031] The first aspect of the present disclosure provides a method for processing waste plastics by fluidized cracking, such as Figure 1 As shown, the method includes the following steps:

[0032] S1, allowing the waste plastic to be processed to enter the waste plastic liquefaction unit for liquefaction treatment to obtain liquefied waste plastic;

[0033] S2, allowing the liquefied waste plastic to enter a waste plastic viscosity reduction unit for visbreaking treatment to obtain visbreaking liquefied waste plastic oil and a first dry gas;

[0034] S3, allowing the visbroken liquefied waste plastic oil to enter a contact cracking reaction unit, where it contacts a fluidized contact agent to undergo a cracking reaction, thereby obtaining reaction oil gas and a regenerated contact agent;

[0035] S4, allowing the reaction oil and gas to enter a separation unit for separation treatment to obtain a second dry gas, liquefied gas, a gasoline fraction, a diesel fraction, and a wax oil fraction;

[0036] The regenerated contact agent is allowed to enter the regeneration unit and is regenerated in the presence of oxygen to obtain regenerated contact agent and regenerated flue gas; the regenerated contact agent is returned to the contact cracking reaction unit for continued use.

[0037] The present disclosure provides a processing method for fluidized cracking of waste plastics, which comprises subjecting the waste plastic raw materials to liquefaction treatment and viscosity-reducing cracking treatment, thereby enabling the waste plastics to be rapidly liquefied and having their viscosity reduced; then, the waste plastics are contacted with a fluidized contact agent for cracking reaction, thereby enabling the waste plastics to be rapidly pyrolyzed in liquid form in contact with the high-temperature contact agent, thereby reducing the residence time of the products to obtain a more ideal product distribution and removing heteroatoms from the waste plastics; through contact cracking to produce gaseous and liquid products, the waste plastics can be recycled as green resources, and the contact agent to be recycled after being regenerated; and the processing method can realize continuous waste plastic processing and improve processing efficiency; the method has strong adaptability to waste plastic raw materials and does not require crushing and cleaning; waste plastics in landfills can be dehydrated, dechlorinated and reduced in situ, and subsequent cracking recovery can be processed centrally, thereby facilitating expansion of production scale and reducing processing costs.

[0038] In a specific embodiment, the waste plastic to be processed includes one or more of low-density polyethylene (LDPE), high-density polyethylene (HDPE), polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET) and polyvinyl chloride (PVC);

[0039] Optionally, the chlorine content of the waste plastic to be processed is less than 10 wt %; the ash content of the waste plastic to be processed is 1 to 40 wt %, preferably 3 to 20 wt %. The waste plastic raw materials disclosed in the present invention can be directly waste plastics from landfills.

[0040] In a preferred embodiment, the waste plastic hot melt dehydration, dechlorination and pulverization unit includes a waste plastic hot melt dehydration and dechlorination unit and a cooling and pulverization unit;

[0041] like Figure 1 As shown, before step S1, the method further includes:

[0042] The chlorine-containing waste plastic raw material is fed into the waste plastic hot melt dehydration, dechlorination and crushing unit of the waste plastic hot melt dehydration and dechlorination unit, and the chlorine-containing waste plastic raw material is melted and dehydrated under a first temperature condition to obtain dehydrated waste plastic; then the dehydrated waste plastic is heated to a second temperature for dechlorination treatment to obtain dehydrated and dechlorinated waste plastic and hydrogen chloride-containing gas;

[0043] The dehydrated and dechlorinated waste plastic is sequentially cooled and crushed in a cooling and crushing unit to obtain dehydrated and dechlorinated waste plastic particles; the dehydrated and dechlorinated waste plastic particles are fed into the waste plastic liquefaction unit; or the dehydrated and dechlorinated waste plastic is directly fed into the waste plastic liquefaction unit.

[0044] In the present disclosure, the waste plastic hot melt dehydration and dechlorination step and the waste plastic liquefaction step can use the same rapid heating liquefaction conveying equipment, or each can use a rapid heating liquefaction conveying equipment; for example, a screw-type heating conveying equipment with heating, etc.

[0045] In a further embodiment, the method further comprises:

[0046] The hydrogen chloride-containing gas is allowed to enter a hydrogen chloride absorption unit and contact with a hydrogen chloride absorbent to perform hydrogen chloride absorption treatment; optionally, the hydrogen chloride-containing gas is allowed to enter the hydrogen chloride absorption unit under the action of a vacuum system.

[0047] The present invention adopts a waste plastic hot-melt dehydration, dechlorination and crushing unit and a hydrogen chloride absorption unit to decompose the chlorine in the waste plastic PVC into the gas phase. A vacuum system is used to quickly separate HCl, avoiding secondary HCl reactions, improving the dechlorination efficiency of the waste plastic, and reducing the corrosion pressure of subsequent equipment.

[0048] In a specific embodiment, the hydrogen chloride absorbent is water or an alkaline solution with a pH greater than 7; optionally, the alkaline solution includes one or more of sodium hydroxide solution, potassium hydroxide solution, calcium hydroxide solution, sodium bicarbonate solution, sodium carbonate solution and ammonia solution.

[0049] In a preferred embodiment, Figure 1 As shown, the method further includes: in step S3, the contact cracking reaction unit performs cracking reaction to obtain ash with carbon;

[0050] The method further includes: passing the carbon-containing ash and the regenerated contact agent into a regeneration unit, and in the presence of oxygen, completely burning the regenerated contact agent and the char on the carbon-containing ash to produce regenerated flue gas and regenerated contact agent. The processing method provided herein can regenerate the carbon-containing regenerated contact agent through a complete combustion reaction, thereby achieving recycling of the contact agent.

[0051] In a preferred embodiment, Figure 1 As shown, the method further includes:

[0052] Allowing at least a portion of the first dry gas and / or at least a portion of the second dry gas to enter the regeneration unit, causing the regenerated contact agent and the carbon-bearing ash to undergo a complete combustion reaction in the presence of oxygen and dry gas to obtain regenerated flue gas and regenerated contact agent;

[0053] Preferably, based on the total weight of the contact agent to be regenerated, the carbon content of the contact agent to be regenerated is 0.5 to 5.0% by weight.

[0054] The present invention uses dry gas generated in the waste plastic processing process to regenerate the regenerated contact agent, thereby improving resource utilization efficiency and contact agent regeneration efficiency.

[0055] In a specific embodiment, when the regeneration flue gas reaches the emission standard, the regeneration flue gas is discharged; wherein the regeneration flue gas emission standard is a conventional standard in this field, for example, refer to GB13271-2014 standard.

[0056] In one embodiment, in step S1, the waste plastic liquefaction unit uses a heating liquefaction conveying device to perform the liquefaction treatment; optionally, the heating liquefaction conveying device includes a first screw-type heating conveying device; preferably, the first screw-type heating conveying device is selected from a twin-screw or single-screw heating conveying device with heating.

[0057] In a preferred embodiment, the process conditions of the liquefaction treatment include: an outlet temperature of 380 to 500° C., preferably 400 to 450° C.; and a residence time of 5 to 30 minutes, preferably 5 to 15 minutes.

[0058] In one embodiment, in step S2, the waste plastic viscosity reduction unit uses a visbreaking reactor to perform the visbreaking treatment; preferably, the visbreaking reactor is an adiabatic visbreaking reactor. In the present disclosure, the adiabatic visbreaking reactor can be any reactor known in the art, such as an upflow visbreaking reactor or a downflow visbreaking reactor.

[0059] In a preferred embodiment, the visbreaking treatment process conditions include: a reaction temperature of 380-500°C, preferably 390-450°C, and more preferably 390-420°C; and a residence time of 10-90 minutes, preferably 20-70 minutes, and more preferably 30-70 minutes. The preferred visbreaking process conditions in this embodiment can achieve a better viscosity reduction effect.

[0060] In one embodiment, in step S3, the process conditions of the cracking reaction include: a reaction temperature of 500-750°C, a weight hourly space velocity of 1-100h -1 The mass ratio of the contact agent to the waste plastic to be treated is 5 to 30: 1. In the present disclosure, the cracking reaction is carried out in a fluidized bed reactor, which is a conventional structure in the art.

[0061] In a preferred embodiment, in step S3, the process conditions of the cracking reaction include: a reaction temperature of 490-750°C, a weight hourly space velocity of 1-100h -1 The mass ratio of the contact agent to the waste plastic to be treated is 6 to 20: 1. Carrying out the cracking reaction according to the process conditions of this embodiment can obtain a more excellent cracking product distribution.

[0062] In a preferred embodiment, the method further comprises: allowing the visbroken liquefied waste plastic oil and steam to enter the contact cracking reaction unit; preferably, the mass ratio of steam to the waste plastic to be treated is 0.05 to 1:1:1, preferably 0.1 to 0.5:1.

[0063] In one embodiment, in step S3, the contact agent is one or more selected from silicon-aluminum material catalyst, quartz sand or coal coke powder; preferably, the particle size of the contact agent is 20 to 3000 μm;

[0064] Optionally, the silicon-aluminum material is selected from a catalyst containing molecular sieves and / or a catalyst not containing molecular sieves; preferably, the catalyst containing molecular sieves is a catalyst containing one or more molecular sieves selected from X molecular sieve, Y molecular sieve, mordenite, ZSM-5, pillared clay molecular sieve, SAPO, or a spent FCC catalyst;

[0065] Preferably, the catalyst not containing molecular sieve is selected from a catalyst prepared using one or more of the first raw materials as raw materials, wherein the first raw materials include amorphous silica-alumina, clay, kaolin, montmorillonite, rectorite, illite, chlorite, pseudo-boehmite and silica; or

[0066] The catalyst not containing molecular sieves is selected from catalysts prepared using one or more of the second raw materials that have been acid-washed, calcined, and sieved as raw materials, wherein the second raw materials include amorphous silica-alumina, clay, kaolin, montmorillonite, rectorite, illite, and chlorite; or selected from catalysts prepared using one or more of the second raw materials that have been acid-washed, calcined, and sieved and pseudo-boehmite and / or silica as raw materials;

[0067] Optionally, the coal coke powder is coal powder and / or petroleum coke powder.

[0068] In one embodiment, the regeneration process is performed in a dense fluidized bed regenerator; preferably, the process conditions for the regeneration process include: an air residence time of 0.5 to 60 seconds, preferably 1.0 to 10 seconds, a dense bed gasification temperature of 600 to 750°C, preferably 600 to 700°C, an oxygen-containing gas volume of 10 to 50% by volume, and a dense bed linear velocity of 0.05 to 0.6 m / s, preferably 0.2 to 0.4 m / s. The dense fluidized bed regenerator in the present disclosure employs a device conventionally selected in the art.

[0069] In one embodiment, the hot melt dehydration and dechlorination unit of the waste plastic hot melt dehydration and dechlorination pulverization unit includes a second screw heating and conveying device and a vacuum device connected to the second screw heating and conveying device; preferably, the second screw heating and conveying device is selected from a twin-screw or single-screw conveying device.

[0070] In a preferred embodiment, the process conditions of the melt dehydration treatment include: a first temperature of 100-170°C, preferably 120-150°C; a time of 0.05-1h, preferably 0.05-0.5h; a feed rate of chlorine-containing waste plastic raw material of 5-5000 kg / h, preferably 100-4000 kg / h; preferably, a heating rate of the melt dehydration treatment of 30-200°C / min, preferably 50-100°C / min;

[0071] Preferably, the process conditions for the dechlorination treatment include: a second temperature of 150-370°C, preferably 220-350°C, and more preferably 300-330°C; a time of 0.05-0.5h, preferably 0.1-0.2h; a vacuum degree of 50-300mmHg, preferably 50-150mmHg; preferably, a heating rate from the first temperature to the second temperature of 50-200°C / min, preferably 50-150°C / min. In the present disclosure, a stepwise heating method is adopted, first heating to the first temperature for melt dehydration treatment, and then heating to the second temperature for dechlorination treatment, to improve the dehydration and dechlorination effect of waste plastics.

[0072] In a specific embodiment, the particle size of the dehydrated and dechlorinated waste plastic particles obtained by the pulverization process is 100 to 2000 μm.

[0073] In the present disclosure, the apparatus and method for the cooling treatment and the pulverizing treatment may be conventional apparatus and method in the art.

[0074] The beneficial effects of the fluidized cracking processing method for waste plastics provided by the present invention overcome technical problems currently existing in the field of pyrolysis treatment of waste plastics. During their research, the inventors discovered that one of the technical problems with the prior art is that polyvinyl chloride (PVC) in waste plastics decomposes upon heating to form HCl, which rapidly reacts with double bonds in the raw materials to form chlorinated hydrocarbons, making it difficult to efficiently remove chlorine from the waste plastics using conventional reaction apparatus. To address this first technical problem, the present invention utilizes specialized equipment to rapidly heat the PVC-containing waste plastics for decomposition, and uses a vacuum method to rapidly separate the decomposed HCl from the reactor, thereby improving dechlorination efficiency. The second technical problem overcome in the prior art: waste plastics are high-molecular polymers. Due to their large molecular weight and solid state, heat transfer within the plastic is very slow. Traditional heating methods can cause excessive heat cracking on the outside of the plastic while the interior remains solid. This results in a high pyrolysis coke rate and a high gas yield for the waste plastics. To address the second difficulty, specialized equipment is used to rapidly heat the waste plastics through strong squeezing and stirring to increase the heating area until the waste plastics become a flowable liquid, reducing the viscosity and allowing them to be transported using a pump. When the waste plastics are rapidly liquefied, the thermal conductivity of the liquid increases significantly, allowing the liquid waste plastics to be pyrolyzed using heating equipment such as a heating furnace, resulting in a high liquid yield and a low coke rate. The third technical problem overcome: the low density of waste plastics leads to a low rate of waste plastic entering the reaction device. The processing scale of existing technologies is small and cannot meet the needs of modern large-scale recycling. To address the third technical problem, after the waste plastics are liquefied, the method provided by the present invention significantly increases the transport density of the raw material compared to solid waste plastics. Therefore, it can not only achieve large-scale waste plastic processing but also achieve continuous waste plastic pyrolysis recovery.

[0075] A second aspect of the present disclosure provides a processing system for fluidized cracking of waste plastics, the system comprising: a waste plastic liquefaction unit, a waste plastic viscosity reduction unit, a contact cracking reaction unit, a separation unit, and a regeneration unit;

[0076] The waste plastic liquefaction unit includes an inlet for waste plastic to be processed and an outlet for liquefied waste plastic, and the waste plastic liquefaction unit is configured to liquefy the waste plastic to be processed;

[0077] The waste plastic viscosity reduction unit includes a liquefied waste plastic inlet, a liquefied waste plastic oil outlet, and a first dry gas outlet. The waste plastic viscosity reduction unit is configured to perform viscosity reduction and cracking treatment on the liquefied waste plastic;

[0078] The contact cracking reaction unit includes a cracking feed inlet, a contact agent inlet, a reaction oil and gas outlet, and a regenerated contact agent outlet; the cracking feed inlet is connected to the liquefied waste plastic oil outlet of the waste plastic viscosity reduction unit, and the contact cracking reaction unit is configured to perform a cracking reaction on the liquefied waste plastic oil;

[0079] The separation unit includes a separation inlet, a second dry gas inlet, a liquefied gas outlet, a gasoline fraction outlet, a diesel fraction outlet and a wax oil fraction outlet; the separation inlet is connected to the reaction oil and gas outlet of the contact cracking reaction unit, and the separation unit is configured to separate the reaction oil and gas; the regeneration unit includes an inlet for a regenerated contact agent, an oxygen-containing gas inlet, a regenerated contact agent outlet and a regenerated flue gas outlet; the regeneration unit is configured to regenerate the regenerated contact agent in the presence of oxygen to obtain a regenerated contact agent and a regenerated flue gas; the regenerated contact agent outlet is connected to the contact agent inlet of the contact cracking reaction unit.

[0080] In a preferred embodiment, the connecting pipeline between the cracking feed inlet of the contact cracking reaction unit and the liquefied waste plastic oil outlet of the waste plastic viscosity reduction unit further includes a steam inlet, which helps to atomize the liquefied waste plastic oil.

[0081] In a preferred embodiment, the regeneration unit further comprises a dry gas inlet, which is connected to the first dry gas outlet of the waste plastic viscosity reduction unit and / or the second dry gas outlet of the separation unit.

[0082] In one embodiment, the processing system further comprises a waste plastic hot melt dehydration and dechlorination unit, a cooling and crushing unit, and a hydrogen chloride absorption unit;

[0083] The waste plastic hot melt dehydration and dechlorination unit includes an inlet for chlorine-containing waste plastic raw materials, an outlet for dehydrated and dechlorinated waste plastics, and an outlet for hydrogen chloride-containing gas; the waste plastic hot melt dehydration and dechlorination unit is configured to perform melting, dehydration, and dechlorination treatment on the chlorine-containing waste plastic;

[0084] The cooling and pulverizing unit is configured to perform cooling and pulverizing treatments on the dehydrated and dechlorinated waste plastics from the waste plastic hot melt dehydration and dechlorination unit;

[0085] The hydrogen chloride absorption unit comprises a hydrogen chloride-containing gas phase material inlet and a hydrogen chloride absorbent; the hydrogen chloride-containing gas phase material inlet is connected to the hydrogen chloride-containing gas outlet of the waste plastic hot melt dehydration and dechlorination unit.

[0086] In a specific embodiment, the waste plastic liquefaction unit includes a heating liquefaction conveying device; optionally, the heating liquefaction conveying device includes a first screw-type heating conveying device; preferably, the first screw-type heating conveying device is selected from a twin-screw or single-screw heating conveying device with heating;

[0087] The waste plastic hot melt dehydration and dechlorination unit includes a second screw heating and conveying device and a vacuum device connected to the second screw heating and conveying device; preferably, the second screw heating and conveying device is selected from a twin-screw or single-screw conveying device.

[0088] In a preferred embodiment, the waste plastic hot melt dehydration and dechlorination unit and the waste plastic liquefaction unit use a heating liquefaction conveying device, including a first screw heating conveying device, and a gas outlet connected to a vacuum device is provided in the middle of the screw heating conveying device.

[0089] In a specific embodiment, the waste plastic hot melt dehydration, dechlorination and pulverization unit further includes a non-condensable steam outlet for leading out the non-condensable steam.

[0090] In a specific embodiment, Figure 1 As shown, a waste plastic fluidized cracking processing system includes: a waste plastic liquefaction unit, a waste plastic viscosity reduction unit, a contact cracking reaction unit, a separation unit, a waste plastic hot melt dehydration and dechlorination unit, a cooling and crushing unit, a hydrogen chloride absorption unit and a regeneration unit;

[0091] The waste plastic hot melt dehydration and dechlorination unit includes an inlet for chlorine-containing waste plastic raw materials, an outlet for dehydrated and dechlorinated waste plastics, and an outlet for hydrogen chloride gas; the waste plastic hot melt dehydration and dechlorination unit is configured to perform melting, dehydration, and dechlorination treatment on the chlorine-containing waste plastic;

[0092] The cooling and pulverizing unit is configured to perform cooling and pulverizing treatments on the dehydrated and dechlorinated waste plastics from the waste plastic hot melt dehydration and dechlorination unit;

[0093] The waste plastic liquefaction unit includes an inlet for waste plastic to be processed and an outlet for liquefied waste plastic. The waste plastic liquefaction unit is configured to liquefy the waste plastic to be processed; wherein the waste plastic to be processed can be the dehydrated and dechlorinated waste plastic particles from the cooling and crushing unit, or the dehydrated and dechlorinated waste plastic from the waste plastic hot-melt dehydration and dechlorination unit;

[0094] The waste plastic viscosity reduction unit includes a liquefied waste plastic inlet, a liquefied waste plastic oil outlet, and a first dry gas outlet. The waste plastic viscosity reduction unit is configured to perform viscosity reduction and cracking treatment on the liquefied waste plastic;

[0095] The contact cracking reaction unit includes a cracking feed inlet, a contact agent inlet, a reaction oil and gas outlet, and a regenerated contact agent outlet; the cracking feed inlet is connected to the liquefied waste plastic oil outlet of the waste plastic viscosity reduction unit, and the contact cracking reaction unit is configured to perform a cracking reaction on the liquefied waste plastic oil; the connecting pipeline between the cracking feed inlet of the contact cracking reaction unit and the liquefied waste plastic oil outlet of the waste plastic viscosity reduction unit also includes a steam inlet;

[0096] The separation unit includes a separation inlet, a second dry gas inlet, a liquefied gas outlet, a gasoline fraction outlet, a diesel fraction outlet, and a wax oil fraction outlet; the separation inlet is connected to the reaction oil and gas outlet of the contact cracking reaction unit, and the separation unit is configured to separate and process the reaction oil and gas;

[0097] The hydrogen chloride absorption unit includes a hydrogen chloride-containing gas phase material inlet and a hydrogen chloride absorbent; the hydrogen chloride-containing gas phase material inlet is connected to the hydrogen chloride-containing gas outlet of the waste plastic hot melt dehydration and dechlorination unit;

[0098] The regeneration unit includes an inlet for the regenerated contact agent, an inlet for the oxygen-containing gas, an outlet for the regenerated agent and an outlet for the flue gas; the inlet for the regenerated contact agent is connected to the outlet for the regenerated contact agent of the contact cracking reaction unit, and the outlet for the regenerated agent is connected to the inlet for the contact agent of the contact cracking reaction unit; preferably, the regeneration unit also includes a dry gas inlet, which is connected to the first dry gas outlet of the waste plastic viscosity reduction unit and / or the second dry gas outlet of the separation unit.

[0099] The process flow of the system provided by the above specific embodiments in this disclosure specifically includes: Figure 1 As shown:

[0100] The waste plastic raw materials stored in the waste plastic storage tank 1 enter the waste plastic hot melt dehydration, dechlorination and pulverization total unit 2 (including the waste plastic hot melt dehydration and dechlorination unit and the cooling and pulverization unit). After dehydration, deaeration and dechlorination in the waste plastic hot melt dehydration and dechlorination unit, dehydrated and dechlorinated waste plastic and hydrogen chloride-containing gas are obtained. The hydrogen chloride-containing gas is pumped into the hydrogen chloride absorption unit 9 through a vacuum system to contact with a hydrogen chloride absorbent for hydrogen chloride absorption treatment. A small amount of non-condensable gas is discharged through pipeline 22. The dehydrated and dechlorinated waste plastic is cooled and pulverized in the cooling and pulverization unit in sequence to obtain dehydrated and dechlorinated waste plastic particles. The dehydrated and dechlorinated waste plastic particles are stored in the waste plastic particle storage tank 3. The dehydrated and dechlorinated waste plastic particles in the waste plastic particle storage tank 3 are fed into the waste plastic liquefaction unit 4 for liquefaction treatment to obtain liquefied waste plastic; the liquefied waste plastic is fed into the waste plastic viscosity reduction unit 5 for viscosity reduction and cracking treatment to obtain liquefied waste plastic oil and the first dry gas; the liquefied waste plastic oil after viscosity reduction is sent to the contact cracking reaction unit 6 through the pipeline 11 and the steam from the pipeline 10, the fresh contact agent replenished from the pipeline 13 and the regenerated contact agent from the pipeline 18 of the regenerator enter the contact cracking reaction unit 6, the viscous liquefied waste plastic oil contacts the fluidized contact agent in the contact cracking reaction unit 6 to carry out cracking reaction, and the reaction oil gas and the contact agent to be regenerated are obtained; the reaction oil gas is passed through the pipeline 12 It enters the subsequent separation unit 8 for separation treatment, wherein: the second dry gas exits the device from pipeline 22, and the liquefied gas, gasoline fraction, diesel fraction and wax oil fraction exit the device from pipeline 16; the charcoaled contact agent to be regenerated and the optional charcoaled ash enter the regeneration unit 7 through pipeline 14, and the coke on the regenerated contact agent and the cracking dry gas from pipeline 21 (including the first dry gas from pipeline 22 and / or the second dry gas from pipeline 15) and the air from pipeline 19 undergo a complete combustion reaction, and the generated regenerated flue gas exits the device through pipeline 17 and can be directly discharged into the atmosphere after meeting the standards. The obtained regenerated contact agent is led out of the regeneration unit 7 through pipeline 18, and the balance agent and ash are unloaded from pipeline 20.

[0101] The present disclosure is further described in detail below through examples. The raw materials used in the examples can be obtained through commercial channels.

[0102] The contact agent SL-1 used is a contact agent containing 10 wt% alumina and 80 wt% kaolin, which is prepared by spray drying and then calcining. The specific preparation method is referred to document CN102974383A; the average particle size of SL-1 is 80 μm.

[0103] The catalytic cracking catalyst used was CRC-1 (produced by Qilu Petrochemical Company), the balance agent of the catalytic cracking catalyst was SL-2, and the average particle size was 65 μm.

[0104] The quartz sand used is SL-3 and has a particle size of 300 μm.

[0105] In the following examples, the residual chlorine content in the waste plastic raw material and the dechlorinated waste plastic liquid material obtained by dechlorination treatment was tested using XRF. The particle size of the contact agent was measured using a particle size detector.

[0106] In the following examples, the high temperature fast pyrolysis chromatograph was manufactured by Frontier Co., Ltd. of Japan and the model number was PY-3030.

[0107] The particle size of the contact agent is measured by a particle size detector.

[0108] The analytical method for chlorine content in liquefied waste plastics is: Q / SH 3360 270-2018.

[0109] The analysis methods for other elements in liquefied waste plastics are: carbon and hydrogen elements SH / T 0656-2017, oxygen element SH / T0986, nitrogen element SH / T 0704-2010, and sulfur element SH / T 0842-2010.

[0110] The cracking product distribution was obtained by the simulated distillation NB / SH / T 0829-2010 method.

[0111] The density analysis method of diesel wax oil is SH / T0604-2000; the cracking gas composition is determined by RIPP78-90 method; the hydrocarbon composition of naphtha, diesel, etc. is determined by chromatography analysis.

[0112] In the following examples, the particle size of the particles obtained by the pulverization process ranges from 5 to 8 mm.

[0113] The contact cracking reactor in the following examples and comparative examples is a fluidized bed reactor.

[0114] Example 1

[0115] The chlorine-containing waste plastic raw materials include: LDPE, HDPE, PS, PP and PVC mixed in a mass percentage of 4:4:8:3:2. The mixed plastic packaging material is crushed and dried. The chlorine content in the mixed plastic is 5.1% by weight. The raw materials are mixed and crushed using a twin-screw heating and conveying equipment at 200°C to obtain hot mixed plastic particles HSL. The properties of the HSL are shown in Table 1.

[0116] Using HSL as raw material, a twin-screw heating and conveying device is used as the equipment for preliminary melting, liquefaction and dechlorination of waste plastics. The feed rate is about 100 kg / h. The chlorine-containing waste plastic raw material is first melted and dehydrated under a first temperature condition to obtain dehydrated waste plastics. The first temperature is 150°C and the time is 3 minutes. The heating rate of the melting and dehydration treatment is 80°C / min.

[0117] Then, the dehydrated waste plastic is heated to a second temperature for dechlorination treatment to obtain dehydrated and dechlorinated waste plastic and hydrogen chloride-containing gas, wherein the second temperature is 320° C., the time is 0.2 h, the vacuum degree is 70 mmHg, and the heating rate from the first temperature to the second temperature is 100° C. / min;

[0118] The dehydrated and dechlorinated waste plastic is subjected to cooling treatment and pulverization treatment in a cooling and pulverization unit in sequence to obtain dehydrated and dechlorinated waste plastic particles DCl-1; the properties of the dehydrated and dechlorinated waste plastic particles DCl-1 are shown in Table 1;

[0119] During the dechlorination process, a vacuum system is used to extract the gaseous material containing hydrogen chloride and send it to a hydrogen chloride absorption unit to contact with a hydrogen chloride absorbent (NaOH solution) for hydrogen chloride absorption treatment.

[0120] The dehydrated and dechlorinated waste plastic particles DCl-1 were then crushed and liquefied using a waste plastic twin-screw high-temperature liquefaction feeding device as a waste plastic liquefaction unit. The process conditions for the liquefaction treatment included: an outlet temperature of 420°C and a residence time of 0.2h. The waste plastic particles were then fed into a visbreaking tank for visbreaking treatment to obtain visbreaking liquefied waste plastic oil and the first dry gas. The visbreaking treatment temperature was 380°C, and samples were taken for analysis after 60 minutes of residence (recorded as DCl-1-60). The viscosity of the visbreaking liquefied waste plastic oil is shown in Table 2.

[0121] Using SL-1 as a contact agent, the visbroken liquefied waste plastic oil and steam enter the contact cracking reaction unit (contact cracking reactor), contact with the fluidized contact agent to carry out a cracking reaction, and obtain reaction oil gas and regenerated contact agent, wherein the mass ratio of the contact agent to the waste plastic raw material is 5:1. The process conditions of the cracking reaction include: reaction temperature of 550℃, weight hourly space velocity of 4h -1The mass ratio of steam to waste plastic to be treated is 0.4:1; the product distribution of cracking reaction products is shown in Table 4.

[0122] Comparative Example 1

[0123] The process flow of Example 1 was similar, using the same waste plastic feedstock. The difference from Example 1 was that dehydrated and dechlorinated waste plastic pellets, DCl-1, were used as the feedstock. Instead of undergoing liquefaction and visbreaking, the pellets were directly introduced into the catalytic cracking reaction unit. In this comparative example, the liquefied waste plastic was too viscous to be dispersed and atomized using steam, and thus could not be continuously fed into the catalytic cracking reaction unit.

[0124] Comparative Example 2

[0125] This comparative example is used to illustrate the process of intermittent cracking of waste plastics in a reactor, which specifically includes:

[0126] The plastic packaging material containing LDPE, HDPE, PS, PP and PVC in a mass percentage of 4:4:8:3:2 was crushed and dried (the chlorine content was 2.6% by weight), and then mixed with cracked wax oil in a weight ratio of mixed waste plastics: cracked wax oil of 3:1, placed in a stirred autoclave, and the air was discharged from the reactor by nitrogen purge. The temperature was set at 350°C and the reaction time was 1h to prepare liquefied waste plastic FSL-1.

[0127] The process conditions of the catalytic cracking reaction with SL-1 as the contact agent include: cracking temperature of 505℃, space velocity of 20h -1 The catalyst-oil ratio was 7, the water-oil ratio was 0.2, and the distribution of the cracked waste plastic oil products was shown in Table 4. The properties of the cracked wax oil used are listed in Table 7.

[0128] Example 2

[0129] Real waste plastic (chlorine content of approximately 3% by weight) was used as a raw material for chlorine-containing waste plastic. A twin-screw heating and conveying apparatus was used as an apparatus for preliminary melting, liquefaction, and dechlorination of the waste plastic. The feed rate was approximately 100 kg / h. The chlorine-containing waste plastic raw material was first melted and dehydrated under a first temperature condition of 150°C for 0.2 hours to obtain dehydrated waste plastic. The heating rate for the melting and dehydration treatment was 90°C / min.

[0130] The dehydrated waste plastic is then heated to a second temperature for dechlorination treatment to obtain dehydrated and dechlorinated waste plastic and hydrogen chloride-containing gas, wherein the second temperature is 300° C., the time is 0.1 h, the vacuum degree is 100 mmHg, and the heating rate from the first temperature to the second temperature is 80° C. / min; the dehydrated and dechlorinated waste plastic is recorded as DCl-2, and the properties of DCl-2 are shown in Table 3;

[0131] During the dechlorination process, a vacuum system is used to extract the gaseous material containing hydrogen chloride and send it to the hydrogen chloride absorption unit, where it comes into contact with the hydrogen chloride absorbent (Ca(OH)2 solution) for hydrogen chloride absorption treatment.

[0132] Then, a waste plastic twin-screw high-temperature liquefaction feeding device was used as a waste plastic liquefaction unit to liquefy the dehydrated and dechlorinated waste plastic DCl-2. The process conditions of the liquefaction treatment included: an outlet temperature of 400°C and a residence time of 0.2h.

[0133] The liquefied dechlorinated waste plastic was then sent to a visbreaking tank for visbreaking treatment to obtain visbreaking liquefied waste plastic oil and the first dry gas. The visbreaking treatment temperature was 400°C. After different residence times (30, 50 and 70 minutes, respectively recorded as DCl-2-30, DCl-2-50 and DCl-2-70), samples were taken for analysis. The viscosity of the visbreaking liquefied waste plastic oil is shown in Table 2.

[0134] Using SL-2 as a contact agent, the visbroken liquefied waste plastic oil and steam enter the contact cracking reaction unit (contact cracking reactor), contact with the fluidized contact agent to carry out a cracking reaction, and obtain reaction oil gas and regenerated contact agent, wherein the mass ratio of the contact agent to the waste plastic raw material is 7:1. The process conditions of the cracking reaction include: reaction temperature of 510℃, weight hourly space velocity of 4h -1 The mass ratio of steam to waste plastic to be treated is 0.1:1; the product distribution of cracking reaction products is shown in Table 4.

[0135] Example 3

[0136] Real waste plastics (chlorine content of about 6% by weight) are used as chlorine-containing waste plastic raw materials, and a twin-screw heating and conveying equipment is used as the equipment for preliminary melting, liquefaction and dechlorination of waste plastics. The feeding rate is about 100 kg / h.

[0137] First, the chlorine-containing waste plastic raw material is subjected to a melting and dehydration treatment under a first temperature condition to obtain dehydrated waste plastic; the first temperature is 130° C.; the time is 0.1 h; and the heating rate of the melting and dehydration treatment is 80° C. / min;

[0138] The dehydrated waste plastic is then heated to a second temperature for dechlorination treatment to obtain dehydrated and dechlorinated waste plastic and hydrogen chloride-containing gas, wherein the second temperature is 320° C., the time is 0.2 h, the vacuum degree is 90 mmHg, and the heating rate from the first temperature to the second temperature is 100° C. / min; the dehydrated and dechlorinated waste plastic is recorded as DCl-3, and the properties of DCl-3 are shown in Table 3;

[0139] During the dechlorination process, a vacuum system is used to extract the gaseous material containing hydrogen chloride and send it to a hydrogen chloride absorption unit to contact with a hydrogen chloride absorbent (NaOH solution) for hydrogen chloride absorption treatment.

[0140] Then, a waste plastic twin-screw high-temperature liquefaction feeding device was used as a waste plastic liquefaction unit to liquefy the dehydrated and dechlorinated waste plastic DCl-3. The process conditions of the liquefaction treatment included: an outlet temperature of 420°C and a residence time of 0.1h.

[0141] The liquefied dechlorinated waste plastic was then sent to a visbreaking tank for visbreaking treatment to obtain visbreaking liquefied waste plastic oil and the first dry gas. The visbreaking treatment temperature was 410°C, and after staying for 20 minutes, a sample was taken for analysis (recorded as DCl-3-20). The viscosity of the visbreaking liquefied waste plastic oil is shown in Table 2.

[0142] Using SL-3 as a contact agent, the visbroken liquefied waste plastic oil and steam enter the contact cracking reaction unit (contact cracking reactor), where they contact the fluidized contact agent for cracking reaction to obtain reaction oil gas and regenerated contact agent. The mass ratio of the contact agent to the waste plastic raw material is 7:1. The process conditions of the cracking reaction include: reaction temperature of 590°C, weight hourly space velocity of 4h -1 The mass ratio of steam to waste plastic to be treated is 0.2:1; the product distribution of the cracking reaction products is listed in Table 4.

[0143] Example 4

[0144] Waste agricultural film (chlorine content of 0.0162% by weight) was placed on a medium-sized experimental device for pyrolysis of waste plastics. A twin-screw heating and conveying device was used as the equipment for preliminary melting, liquefaction and dechlorination of the waste plastics. The feed rate was about 5 kg / h. The process conditions for melting and dehydration treatment included: a first temperature of 150°C; a time of 0.1 h; the process conditions for dechlorination treatment included: a second temperature of 300°C; a time of 0.1 h, and a heating rate from the first temperature to the second temperature of 100°C / min; the vacuum degree of the screw heating and conveying device was 150 mmHg. A dehydrated and dechlorinated waste plastic sample DCl-4 was obtained, and its properties are shown in Table 3.

[0145] The same twin-screw heating and conveying equipment was continued to be used to liquefy the dehydrated and dechlorinated waste plastics. The process conditions of the liquefaction treatment included: the outlet temperature listed in Table 6, the residence time was 0.2 h, and liquefied waste plastics were obtained;

[0146] The liquefied waste plastic was then passed from the outlet of the twin-screw heating and conveying equipment into a visbreaking reactor, where it was visbroken at different temperatures and residence times to obtain a series of visbreaking waste plastic samples DC1-4. The internal temperature of the visbreaking reactor, the visbreaking reaction time, and the viscosity of the visbreaking waste plastic are listed in Table 6.

[0147] Example 5

[0148] Using DCl-4-2-60 as raw material and SL-2 as contact agent, the visbroken liquefied waste plastic oil and steam are introduced into a contact cracking reaction unit (contact cracking reactor) to contact with the fluidized contact agent for cracking reaction, thereby obtaining reaction oil gas and regenerated contact agent. The mass ratio of the contact agent to the waste plastic raw material is 7:1. The process conditions of the cracking reaction include: reaction temperature of 510°C, weight hourly space velocity of 4h -1 The mass ratio of steam to waste plastic to be treated is 0.4:1; the product distribution of cracking reaction products is shown in Table 5.

[0149] Example 6

[0150] Using DCl-4-2-60 as feedstock, the same process as in Example 5 was employed, except that SL-1 was used as the contact agent. The spent contact agent (1.3 wt% carbon content) obtained from the cracking reaction unit was introduced into the regeneration unit for regeneration. The regeneration process was performed in a dense fluidized bed regenerator. The regeneration process conditions included an air residence time of 3 s, a dense bed gasification temperature of 660°C, a gas containing 21 vol% oxygen, and a dense bed linear velocity of 0.3 m / s. The regenerated contact agent was introduced into the cracking reaction unit along with fresh contact agent (the weight ratio of regenerated contact agent to fresh contact agent was 20:1). Furthermore, the first dry gas generated from the waste plastics visbreaking reactor and the second dry gas from the separation unit were introduced into the regenerator for continued use, resulting in complete combustion of the spent contact agent. (The amounts of the first and second dry gases introduced can be adjusted based on the actual regeneration and combustion conditions.) Other process conditions were the same as in Example 5. The product distribution of the cracking reaction products is shown in Table 5.

[0151] Example 7

[0152] Referring to the process flow in Example 1, the difference between this embodiment and Example 1 is that the process conditions are changed, specifically including:

[0153] The feed rate of chlorinated waste plastic raw materials was 100 kg / h. The process conditions for the melting dehydration treatment included: a first temperature of 100°C and a time of 0.5 h; the process conditions for the dechlorination treatment included: a second temperature of 200°C and a time of 0.05 h; a vacuum degree of 150 mmHg; and a heating rate from the first temperature to the second temperature of 50°C / min. The properties of the dehydrated and dechlorinated waste plastic particles DCl-7 are shown in Table 1.

[0154] The process conditions for liquefaction treatment include: outlet temperature of 380°C; residence time of 5 min; the process conditions for visbreaking treatment include: reaction temperature of 380°C, residence time of 10 min; the viscosity of the visbreaking liquefied waste plastic oil is shown in Table 2;

[0155] The process conditions of the cracking reaction include: reaction temperature of 650℃, weight hourly space velocity of 5h -1 The mass ratio of the contact agent to the waste plastic to be treated is 30:1; the mass ratio of the steam to the waste plastic to be treated is 0.05:1; the product distribution of the cracking reaction products is shown in Table 5.

[0156] Example 8

[0157] LDPE, HDPE, PS, PP, and PVC were mixed in a mass ratio of 4:4:8:3:1 and then crushed and dried. The mixed plastic packaging material had a chlorine content of 2.9% by weight. A twin-screw heated conveying apparatus was used for the initial melting, liquefaction, and dechlorination of the waste plastics at a feed rate of approximately 100 kg / h. The test process varied the outlet temperature, with the treatment time at each outlet temperature being 0.1 h. The vacuum level of the screw heated conveying apparatus was 100 mmHg. The morphology and chlorine content of the waste plastics after conveying were tested under different outlet temperature conditions. A series of liquefied, dechlorinated waste plastics, DCl-8-1 to DCl-8-8, were obtained. The properties of the resulting liquefied, dechlorinated waste plastics, DCl-8-1 to DCl-8-8, are shown in Table 8.

[0158] During the dechlorination process, a vacuum system is used to extract the gaseous material containing hydrogen chloride and send it to a hydrogen chloride absorption unit to contact with a hydrogen chloride absorbent (NaOH solution) for hydrogen chloride absorption treatment.

[0159] Example 9

[0160] The liquefied dechlorinated waste plastic DCl-8-3 in Example 8 was further heated to 390° C. for 0.2 h using a screw heating and conveying device (liquefaction process); then, the rotational viscosity was measured after being kept at 390° C. for 30 min, 50 min, and 70 min (using an adiabatic upflow visbreaking reactor) to obtain visbroken liquefied waste plastic oils (respectively designated as DCl8-3-30, DCl8-3-50, and DCl8-3-70). The properties of the visbroken liquefied waste plastic oils are shown in Table 9.

[0161] The liquefied dechlorinated waste plastic DCl-8-6 in Example 8 was heated to 250°C using a screw heating and conveying device and directly squeezed into a normal pressure container with an internal temperature of 250°C and a gas outlet. The temperature was kept for 60 minutes, and a sample DCl-8-6-60 was taken to test the viscosity. Its viscosity was too high and exceeded the measurement range. Its form was a plastic solid and could not flow freely.

[0162] Example 10

[0163] Using SL-1 as a contact agent, the visbroken liquefied waste plastic oil DCl-8-3-70 in Example 9 and steam were introduced into a contact cracking reaction unit (contact cracking reactor) to contact with the fluidized contact agent for cracking reaction to obtain reaction oil gas and regenerated contact agent, wherein the mass ratio of the contact agent to the waste plastic raw material was 7:1. The process conditions of the cracking reaction included: a reaction temperature of 550°C, a weight hourly space velocity of 4h -1 The mass ratio of steam to waste plastic to be treated is 0.3:1; the product distribution of cracking reaction products is shown in Table 5.

[0164] Table 1 Properties of liquefied waste plastics

[0165]

[0166] Table 2 Viscosity of viscous plastics

[0167]

[0168] Table 3 Properties of real waste plastics output from screw heating conveying equipment

[0169] Example Example 2 Example 3 Example 4 Sample name DCl-2 DCl-3 DCl-4 W (ash content) / % 20.204 11.363 2.86 W(O) / % 8.38 8.43 1.45 W(C) / % 66.94 66.02 83.28 W(H) / % 9.23 9.47 13.25 W(S) / % 0.053 0.084 <0.1 W(N) / % 0.31 0.18 0.028 W(Cl) / % 0.473 0.834 0.0162 W (metal analysis) / (μg / g) Al 0.329 0.506 - Ca 6.934 6.326 0.709 Fe 0.434 0.894 - Mg 0.065 0.165 - Na - 0.123 - Si 0.411 0.852 0.131 Ti 0.252 0.211 -

[0170] Table 4 Distribution of waste plastic pyrolysis products (dry basis)

[0171] Example 1 Comparative Example 2 Example 2 Example 3 CO / weight% 0.00 0.00 0.30 0.22 <![CDATA[CO2 / wt%]]> 0.00 0.00 1.20 1.04 Dry gas / weight% 0.98 1.18 0.82 0.88 Liquefied gas / weight% 11.71 5.38 3.42 6.19 Gasoline (<205℃) / weight% 63.11 23.28 32.93 35.33 Diesel (205-350°C) / weight% 9.82 17.30 35.85 33.58 Wax oil (350~524℃) / weight% 3.27 39.97 7.47 6.97 Heavy wax oil (>524℃) / weight% 0.00 12.89 0.60 0.86 Coke / weight% 11.11 <1 17.41 14.93 Total / weight% 100.00 100.00 100.00 100.00 w(Si product) / (μg / g) <1 <1 <1 <1 w(Cl) / (μg / g) 50 270 9 15

[0172] Table 5 Distribution of pyrolysis products of waste plastics (dry basis)

[0173] Example 5 Example 6 Example 7 Example 10 CO / weight% 0.04 0.03 0.00 0.00 <![CDATA[CO2 / wt%]]> 0.45 0.60 0.00 0.00 Dry gas / weight% 1.73 0.81 2.15 0.91 Liquefied gas / weight% 23.05 18.39 20.72 11.34 Gasoline (<205℃) / weight% 55.51 63.57 42.96 59.78 Diesel (205-350°C) / weight% 8.84 10.10 8.45 11.28 Wax oil (350~524℃) / weight% 3.15 2.15 3.89 4.13 Heavy wax oil (>524℃) / weight% 0.00 0.00 0.00 0 Coke / weight% 7.23 4.35 21.83 12.56 Total / weight% 100.00 100.00 100.00 100 w(Si product) / (μg / g) <1 <1 <1 <1 w(Cl) / (μg / g) <3 <5 32 26

[0174] Table 6 Properties of Viscosity Reduction Waste Plastics

[0175]

[0176] In Table 6, the “-” column in the viscosity column indicates that the viscosity is too high to be tested.

[0177] Table 7 Properties of cracked gas oil

[0178] Density (20℃) / (g / cm3) 1.1415 Total acid value / (mgKOH / 100mL) 0.1 Residual carbon value / % 5.08 w(element) / % C 89.88 H 6.52 S 3.30 N 0.30 w(metal) / (μg / g) Fe 4.9 Ni 1.3 V <0.1 Na 1.0 Ca 0.6 w(four-component composition) / % Saturated hydrocarbons 3.3 Aromatics 82.4 colloid 13.3 Asphaltene 1.0

[0179] Table 8 Properties of liquefied waste plastics in Example 8

[0180] Sample name DCl-8-1 DCl-8-2 DCl-8-3 DCl-8-4 DCl-8-5 DCl-8-6 DCl-8-7 Outlet temperature 330 320 310 300 285 250 220 w(Cl) / (μg / g) 750 1630 1720 2900 6430 11410 20223 Dechlorination rate / weight% 97.41 94.38 94.07 90.00 77.83 59.82 28.79

[0181] Table 9 Viscosity of the deviscosity reducing plastic oil in Example 9

[0182] Sample name DCl-8-3-30 DCl-8-3-50 DCl-8-3-70 DCl-8-6-60 Viscosity reduction temperature / ℃ 390 390 390 250 Viscosity reduction time / min 30 50 70 60 Viscosity / (cP200℃) 543 330.8 268.5 -

[0183] In Table 9, the “-” column in the viscosity column indicates that the viscosity is too high to be tested.

[0184] As can be seen from Example 1, after the mixed plastics are melted and liquefied by a twin-screw pump and dechlorinated, most of the chlorine in the waste plastics is removed; the dechlorinated plastic DCl-1 is decomposed at 550°C to obtain dry gas, liquefied gas, gasoline, diesel, wax oil and coke, of which the liquid yield reaches 87.91% by weight and the gasoline fraction yield reaches 63.11% by weight.

[0185] It can be seen from Comparative Example 1 that the viscosity of the plastic liquefied by dechlorination alone is still very high and the liquid fluidized cracking process cannot be used.

[0186] It can be seen from Comparative Example 2 that after the dechlorinated liquefied plastic is diluted with a solvent, a liquid fluidized cracking process can be used. However, compared with Example 1, the comparative example needs to introduce cracked wax oil as a solvent, which increases the energy consumption and other costs of the processing process. This shows that the method provided by the present disclosure simplifies the process energy consumption and investment, and can obtain a higher yield of light fractions (such as gasoline and diesel).

[0187] As shown in Example 2, dechlorinated plastic DCl-2 was subjected to a cracking reaction at 510°C using an FCC balancer (SL-2) as a heat carrier to produce dry gas, liquefied gas, gasoline, diesel, wax oil, and coke. After ash removal, the material balance showed a liquid yield of 80.27% by weight and a gasoline fraction yield of 32.93% by weight. Furthermore, the waste plastics processing process provided herein substantially removes Cl and Si from the waste plastics liquid product.

[0188] As shown in Example 3, the majority of chlorine in the waste plastic was removed after the twin-screw pump melt-liquefaction dechlorination process. At 590°C, using quartz sand as a catalytic carrier, the resulting catalytic cracking reaction yielded dry gas, liquefied petroleum gas, gasoline, diesel, wax oil, and coke. After ash removal, the material balance showed a liquid yield of 82.93% by weight and a gasoline fraction yield of 35.33% by weight. Furthermore, the waste plastic treatment process provided by this disclosure substantially removed Cl and Si from the waste plastic liquid product.

[0189] As shown in Example 4, after the waste agricultural film plastic undergoes a twin-screw pump melt-liquefaction dechlorination process, it enters the visbreaking process. Through varying temperatures and durations, the viscosity reduction rate decreases significantly, meeting the requirements of the contact cracking process. Furthermore, Table 5 shows that when the "liquefaction outlet temperature of 400-450°C and the visbreaking reaction temperature of 390-450°C" are met, the resulting visbroken liquefied waste plastic oil has a lower viscosity.

[0190] As shown in Example 5, after the waste agricultural film plastics were melted and liquefied using a twin-screw pump for dechlorination, a cracking reaction was conducted at 510°C using an FCC balancer as a catalyst support, yielding dry gas, liquefied gas, gasoline, diesel, wax oil, and coke. After ash removal, the material balance showed a liquid yield of 90.55% by weight and a gasoline fraction yield of 55.51% by weight. Furthermore, the waste plastics treatment process provided by this disclosure substantially removed Cl and Si from the waste plastics liquid product.

[0191] Comparing Example 1 with Example 7, it can be seen that the process parameters adopted in the treatment process of Example 1 are the preferred technical scheme. Combined with the analytical data in Tables 1 and 2, it can be seen that the dechlorinated waste plastic DCl-1 obtained in Example 1 has a lower chlorine content and a better dechlorination effect; the viscosity-reduced waste plastic DCl-1-60 obtained in Example 1 has a lower viscosity and a better viscosity-reducing effect; combined with the product distribution data in Table 4, it can be seen that the liquid yield of the product obtained in Example 1 is higher, especially the gasoline fraction yield is higher.

[0192] According to the data in Table 8, by comparing DCl-8-1 to DCl-8-5 with DCl-8-6 and DCl-8-7 in Comparative Example 3, it can be seen that DCl-8-1 to DCl-8-4 meet the "dechlorination outlet temperature of 300 to 330°C" during the hot melt dechlorination treatment of waste plastics, and the dechlorination rate of the obtained liquefied dechlorinated waste plastics is higher.

[0193] According to the data in Table 9, it can be seen that when the viscosity reduction treatment meets the reaction temperature of 390-420°C and the residence time of 30-70 minutes, the viscosity reduction effect on waste plastics is better.

[0194] The preferred embodiments of the present disclosure are described in detail above. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0195] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0196] In addition, the various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A processing method for fluidized cracking of waste plastics, characterized in that: The method comprises the following steps: S1. Allowing the waste plastic to be processed to enter a waste plastic liquefaction unit for liquefaction treatment to obtain liquefied waste plastic; wherein the waste plastic liquefaction unit uses a heating liquefaction conveying device to perform the liquefaction treatment; the heating liquefaction conveying device includes a first screw-type heating conveying device; the process conditions of the liquefaction treatment include: an outlet temperature of 400-450° C.; and a residence time of 5-15 minutes; S2. The liquefied waste plastic enters a waste plastic viscosity reducing unit for visbreaking treatment to obtain visbreaking liquefied waste plastic oil and a first dry gas; the process conditions of the visbreaking treatment include: a reaction temperature of 380-420° C.; a residence time of 40-60 min; S3. The visbroken liquefied waste plastic oil is allowed to enter a contact cracking reaction unit, where it contacts a fluidized contact agent to undergo a cracking reaction, thereby obtaining reaction oil gas and a regenerated contact agent. The process conditions for the cracking reaction include: a reaction temperature of 500-650° C., a weight hourly space velocity of 3-60 h / min, and a reaction temperature of 100-2000 ° C. -1 , the mass ratio of the contact agent to the waste plastic to be treated is 5-20:1; the visbroken liquefied waste plastic oil and steam are allowed to enter the contact cracking reaction unit; the mass ratio of steam to the waste plastic to be treated is 0.1-0.5:1; S4, allowing the reaction oil and gas to enter a separation unit for separation treatment to obtain a second dry gas, liquefied gas, a gasoline fraction, a diesel fraction, and a wax oil fraction; The regenerated contact agent is allowed to enter the regeneration unit and is regenerated in the presence of oxygen to obtain regenerated contact agent and regenerated flue gas; the regenerated contact agent is returned to the contact cracking reaction unit for continued use.

2. The processing method according to claim 1, characterized in that: Before step S1, the method further includes: The chlorine-containing waste plastic raw material is fed into a waste plastic hot melt dehydration and dechlorination unit, and the chlorine-containing waste plastic raw material is melted and dehydrated under a first temperature condition to obtain dehydrated waste plastic; the dehydrated waste plastic is then heated to a second temperature for dechlorination treatment to obtain dehydrated and dechlorinated waste plastic and hydrogen chloride-containing gas; The dehydrated and dechlorinated waste plastic is subjected to cooling treatment and crushing treatment in a cooling and crushing unit in sequence to obtain dehydrated and dechlorinated waste plastic particles; the dehydrated and dechlorinated waste plastic particles are fed into the waste plastic liquefaction unit; or The dehydrated and dechlorinated waste plastics are directly fed into the waste plastics liquefaction unit.

3. The processing method according to claim 2, characterized in that: The method further includes: The hydrogen chloride-containing gas enters a hydrogen chloride absorption unit and contacts with a hydrogen chloride absorbent to absorb hydrogen chloride; The hydrogen chloride absorbent is water or an alkaline solution with a pH greater than 7.

4. The processing method according to claim 3, characterized in that: The method includes: The hydrogen chloride-containing gas is allowed to enter the hydrogen chloride absorption unit under the action of a vacuum system.

5. The processing method according to claim 3, characterized in that: The alkali solution includes one or more of sodium hydroxide solution, potassium hydroxide solution, calcium hydroxide solution, sodium bicarbonate solution, sodium carbonate solution and ammonia water.

6. The processing method according to claim 1, characterized in that: The contact cracking reaction unit in step S3 performs cracking reaction to obtain charcoal ash; The method also includes: allowing the charcoal-bearing ash and the regenerated contact agent to enter a regeneration unit, and in the presence of oxygen, causing the regenerated contact agent and the char on the charcoal-bearing ash to undergo a complete combustion reaction to obtain regenerated flue gas and regenerated contact agent.

7. The processing method according to claim 6, characterized in that: The method further includes: At least a portion of the first dry gas and / or at least a portion of the second dry gas is allowed to enter the regeneration unit, so that the regenerated contact agent and the carbon-bearing ash undergo a complete combustion reaction in the presence of oxygen and dry gas to obtain regenerated flue gas and regenerated contact agent.

8. The processing method according to claim 6, characterized in that: Based on the total weight of the contact agent to be regenerated, the carbon content of the contact agent to be regenerated is 0.5-5.0% by weight.

9. The processing method according to claim 1, characterized in that: In step S1, the first screw heating and conveying device is selected from a twin-screw or single-screw heating and conveying device with heating.

10. The processing method according to claim 1, characterized in that: In step S2, the waste plastic viscosity reduction unit uses a viscosity reduction reactor to perform the viscosity reduction and cracking treatment.

11. The processing method according to claim 10, characterized in that: The visbreaking reactor is an adiabatic visbreaking reactor.

12. The processing method according to claim 1, characterized in that: In step S3, the contact agent is one or more selected from silicon-aluminum material catalyst, quartz sand or coal coke powder.

13. The processing method according to claim 12, characterized in that: The particle size of the contact agent is 20-3000 μm.

14. The processing method according to claim 12, characterized in that: The silicon-aluminum material catalyst is selected from a catalyst containing molecular sieves and / or a catalyst not containing molecular sieves.

15. The processing method according to claim 14, characterized in that: The molecular sieve-containing catalyst is selected from one or more of a catalyst containing X molecular sieve, a catalyst containing Y molecular sieve, a catalyst containing mordenite, a catalyst containing ZSM-5 molecular sieve, a catalyst containing pillared clay molecular sieve, a catalyst containing SAPO molecular sieve and a spent FCC catalyst.

16. The processing method according to claim 14, characterized in that: The catalyst not containing molecular sieve is selected from catalysts prepared with one or more of the first raw materials as raw materials, wherein the first raw materials include amorphous silica-alumina, clay, kaolin, montmorillonite, rectorite, illite, chlorite, pseudo-boehmite and silicon dioxide; or The catalyst not containing molecular sieves is selected from a catalyst prepared using one or more of the second raw materials that have been acid-washed, calcined, and sieved as raw materials, the second raw materials including amorphous silica-alumina, clay, kaolin, montmorillonite, rectorite, illite, and chlorite; or selected from a catalyst prepared using one or more of the second raw materials that have been acid-washed, calcined, and sieved and pseudo-boehmite and / or silica as raw materials.

17. The processing method according to claim 12, characterized in that: The coal coke powder is coal powder and / or petroleum coke powder.

18. The processing method according to claim 6, characterized in that: The regeneration process is carried out in a dense phase fluidized bed regenerator.

19. The processing method according to claim 18, characterized in that: The process conditions of the regeneration treatment include: an air residence time of 0.5 to 60 seconds, a dense bed gasification temperature of 600 to 750° C., an oxygen-containing gas volume of 10 to 50% by volume, and a dense bed linear velocity of 0.05 to 0.6 m / s.

20. The processing method according to claim 19, characterized in that: The process conditions of the regeneration treatment include: an air residence time of 1.0 to 10 seconds, a gasification temperature of the dense bed of 600 to 700° C., and a linear velocity of the dense bed of 0.2 to 0.4 m / s.

21. The processing method according to claim 2, characterized in that: The waste plastic hot melt dehydration and dechlorination unit comprises a second screw-type heating and conveying device and a vacuum device connected to the second screw-type heating and conveying device.

22. The processing method according to claim 21, characterized in that: The second screw-type heating and conveying equipment is selected from a twin-screw or single-screw conveying equipment.

23. The processing method according to claim 21, characterized in that: The process conditions of the melting dehydration treatment include: a first temperature of 100-170° C.; a time of 0.05-1 h; and a feed rate of chlorine-containing waste plastic raw materials of 5-5000 kg / h.

24. The processing method according to claim 23, characterized in that: The process conditions of the melting and dehydration treatment include: a first temperature of 120-150° C.; a time of 0.05-0.5 h; and a feed rate of chlorine-containing waste plastic raw materials of 100-4000 kg / h.

25. The processing method according to claim 21, characterized in that: The process conditions of the dechlorination treatment include: a second temperature of 150-370° C.; a time of 0.05-0.5 h; and a vacuum degree of 50-300 mmHg.

26. The processing method according to claim 25, characterized in that: The process conditions of the dechlorination treatment include: a second temperature of 220-350° C.; a time of 0.1-0.2 h; and a vacuum degree of 50-150 mmHg.

27. The processing method according to claim 26, characterized in that: The process conditions of the dechlorination treatment include: the second temperature is 300-330°C.

28. The processing method according to claim 21, characterized in that: The heating rate from the first temperature to the second temperature is 50-200°C / min.

29. The processing method according to claim 28, characterized in that: The heating rate from the first temperature to the second temperature is 50-150°C / min.

30. The processing method according to claim 21, characterized in that: The particle size of the dehydrated and dechlorinated waste plastic particles obtained through the crushing process is 100-2000 μm.

31. The processing method according to claim 1, characterized in that: The waste plastics to be processed include one or more of LDPE, HDPE, PS, PP, PET and PVC.

32. The processing method according to claim 31, characterized in that: The chlorine content of the waste plastic to be processed is less than 10% by weight; the ash content of the waste plastic to be processed is 1-40% by weight.

33. The processing method according to claim 32, characterized in that: The ash content in the waste plastic to be processed is 3 to 20% by weight.

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