Multiple fluidized or spouted bed reactors for plastic pyrolysis.

Abstract

A system for converting plastics includes a catalyst regenerator, a feeder containing a plastic feedstock, a first conical spouted bed reactor stage in fluid communication with the catalyst regenerator and in fluid communication with the feeder, and a second conical spouted bed reactor stage in fluid communication with the first conical spouted bed reactor stage.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 252,929, filed October 6, 2021, which is hereby incorporated by reference in its entirety for all purposes.

[0002] FIELD OF THEINVENTION This technology relates generally to the conversion of plastics to lower molecular weight hydrocarbon products. Specifically, this technology relates to the use of in-line conical spouted bed reactors to convert plastic feedstocks to olefins and aromatic products by pyrolysis. [Background technology]

[0003] Plastic waste is a growing problem because the materials are not biodegradable. However, many plastic materials are excellent candidates for creating a circular economy, a paradigm in which 100% of waste can be recycled or used to generate raw materials for other useful materials.

[0004] Pyrolysis of waste plastics in fluidized or spouted bed reactors has been proposed as a promising route for converting waste plastics into liquid fuels or chemical feedstocks, which can be used to make recycled plastics. The majority of published studies rely on fixed fluidized or spouted beds, where millimeter-sized plastics are continuously injected into a fixed bed of catalyst. Although catalytic pyrolysis has been widely studied, there is still a need to develop more efficient catalytic pyrolysis methods that maximize the yield of desirable products such as light olefins and aromatics and minimize the yield of undesirable products such as methane and ethane. Propylene, in particular, is a specialty light olefin in high demand, as it is used in many of the world's largest and fastest growing synthetic materials and thermoplastics.

[0005] The present disclosure provides systems and processes capable of producing olefins, such as propylene, and aromatic products with high selectivity from plastic feedstocks. Summary of the Invention

[0006] Pyrolysis of plastics in fluidized bed and spouted bed reactors has been proposed as a promising route to produce olefins and aromatics. However, such proposals have significant problems that have not been fully resolved to date. Pyrolysis of millimeter-sized plastic particles in fluidized bed or spouted bed reactors occurs on a time scale of hundreds of seconds. In fluidized bed or spouted bed reactors, the catalyst flow is highly backmixed and the catalyst residence time distribution is non-uniform. Due to the constant circulation of catalyst between the reactor and the catalyst regenerator and the non-uniform catalyst and plastic residence time distribution in the reactor at any given time, unconverted plastic is entrained as it enters the regenerator. The present invention solves this problem by having two or more fluidized beds or spouted beds in series, thereby significantly narrowing the catalyst and plastic residence time distribution and lowering the proportion of unconverted plastic entrained by the catalyst circulating from the reactor to the regenerator.

[0007] In a first aspect, disclosed herein is a system for converting plastics to lower molecular weight products, the system comprising a catalyst regenerator, a feeder containing a plastic feedstock, a first conical spouted bed reactor stage in fluid communication with the catalyst regenerator and in fluid communication with the feeder, and a second conical spouted bed reactor stage in fluid communication with the first conical spouted bed reactor stage. In some embodiments, a third conical spouted bed reactor stage in fluid communication with the second conical spouted bed reactor stage is used.

[0008] In some embodiments, the first and second conical spouted bed reactor stages are contained within a single reactor vessel. In some of these embodiments, the first and second conical spouted bed reactor stages are at least partially separated by a baffle. In some of these embodiments, the baffle defines an opening at the top, bottom, or one or more sides of the first reactor stage.

[0009] In other embodiments, each conical spouted bed reactor stage is contained within a separate reactor vessel. In some of these embodiments, the vessels are located at different heights.

[0010] In some embodiments, the material in the reactor stage, including the catalyst and unreacted plastic feedstock, can proceed from the first reactor stage to the second reactor stage via a pipe or other passageway. In some of these embodiments, the pipe or passageway is vented so that the flow of catalyst and unreacted feedstock is pneumatically driven from the first reactor stage to the second reactor stage.

[0011] In some embodiments, the first conical spouted bed reactor stage is configured to receive catalyst from a catalyst regenerator. In some of these embodiments, the flow of catalyst from the catalyst regenerator to the first conical spouted bed reactor stage is adjustable in response to the temperature in the first conical spouted bed reactor stage falling below a predetermined temperature set point. In some embodiments, the second reactor stage is also in fluid communication with the catalyst regenerator and configured to receive catalyst from the catalyst regenerator. In some of these embodiments, the flow of catalyst from the catalyst regenerator to the second conical spouted bed reactor stage is adjustable in response to the temperature in the second conical spouted bed reactor stage falling below a predetermined temperature set point. In some embodiments, the third reactor stage is also in fluid communication with the catalyst regenerator and configured to receive catalyst from the catalyst regenerator. In some of these embodiments, the flow of catalyst from the catalyst regenerator to the third conical spouted bed reactor stage is adjustable in response to the temperature in the third conical spouted bed reactor stage falling below a predetermined temperature set point.

[0012] In some embodiments, the reactor stages include draft tubes, each extending from the bottom of an associated reactor stage toward the top of the reactor stage, the draft tubes comprising a cylindrical tube having an outer diameter smaller than the inner diameter of the bottom of the reactor stage and at least one opening extending upwardly from the bottom of the draft tube.

[0013] In some embodiments, the reactor stages include confinement devices, each of which extends from a top of an associated reactor stage toward a bottom of the reactor stage, the confinement device comprising a cylindrical tube having an outer diameter smaller than the inner diameter of the top of the reactor stage.

[0014] In some embodiments, the first conical spouted bed reactor stage operates at a temperature of about 300° C. to about 650° C., or about 450° C. to about 600° C., or about 480° C. to about 550° C. In some embodiments, the second conical spouted bed reactor stage operates at a temperature of about 300° C. to about 650° C., or about 450° C. to about 600° C., or about 480° C. to about 550° C.

[0015] In some embodiments, the system further comprises a gas supply system in fluid communication with the first and second conical spouted bed reactor stages, the gas supply system configured to supply a driving gas to the first and second conical spouted bed reactor stages. In some of these embodiments, the driving gas contains less than 1.0 wt. % oxygen or more preferably less than 0.1 wt. % oxygen.

[0016] In some embodiments, the system comprises a set of separating cyclones in fluid communication with the first conical spouted bed reactor stage and the second conical spouted bed reactor stage.

[0017] In a second aspect, a method of producing hydrocarbon products from plastics is disclosed, the method including: feeding a plastic feedstock and a drive gas to a first conical spouted bed reactor stage containing a catalyst to produce a first product vapor and a first residual plastic; separating at least a portion of the first product vapor from the drive gas and the first residual plastic to produce a first product stream comprising the first product vapor; feeding the first residual plastic from the first conical spouted bed reactor stage and the drive gas to a second conical spouted bed reactor stage containing a catalyst to produce a second product vapor and a second residual plastic; and separating at least a portion of the second product vapor from the drive gas and the second residual plastic to produce a second product stream comprising the second product vapor.

[0018] In some embodiments, the method includes transferring at least a portion of the catalyst from the first conical spouted bed reactor stage to the second conical spouted bed reactor stage. In some embodiments, the method includes transferring at least a portion of the catalyst from the second conical spouted bed reactor stage to a regenerator. In some embodiments, the method includes supplying catalyst from the regenerator to the first conical spouted bed reactor stage. In some embodiments, the method includes supplying catalyst from the regenerator to the second conical spouted bed reactor stage. In some embodiments, the transfer of the portion of the catalyst from the first conical spouted bed reactor stage to the second conical spouted bed reactor stage is driven, at least in part, by the flow of the driving gas. In some embodiments, the transfer of the portion of the catalyst from the second conical spouted bed reactor stage to the regenerator is driven, at least in part, by the flow of the driving gas.

[0019] In some embodiments, the first conical spouted bed reactor stage has a temperature of about 300°C to about 650°C, or about 450°C to about 600°C, or about 480°C to about 550°C. In some of these embodiments, the temperature of the first conical spouted bed reactor stage is controlled in part by supplying hot catalyst from a regenerator to the first conical spouted bed reactor stage. In some embodiments, the second conical spouted bed reactor stage has a temperature of about 300°C to about 650°C, or about 450°C to about 600°C, or about 480°C to about 550°C. In some of these embodiments, the temperature of the second conical spouted bed reactor stage is controlled in part by supplying hot catalyst from a regenerator to the second conical spouted bed reactor stage.

[0020] In some embodiments, the plastic feedstock is first shredded to a nominal size of about 1 mm to about 20 mm, or preferably about 8 mm to about 10 mm, and then fed to a first conical spouted bed reactor stage. In some embodiments, the method includes feeding the second residual plastic from the second conical spouted bed reactor stage and a driving gas to a third conical spouted bed reactor stage containing a catalyst to produce a third product stream and a residue, and separating the third product stream, the driving gas, and the residue to produce a third product stream comprising the third product stream.

[0021] In some embodiments, the method includes directing the first and second product streams into a cyclone separator. In some of these embodiments, the first and second product streams are combined prior to being directed into the cyclone separator. In some embodiments, the method includes collecting the first and second product streams in a separation vessel. In some embodiments, the plastic feedstock includes high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, or a mixture of any two or more thereof.

[0022] In some embodiments, the first and second hydrocarbon products are C1-C 12 Saturated hydrocarbons, C1-C 12 In some embodiments, the first and second hydrocarbon products may be the same or different, hi some embodiments, the hydrocarbon product comprises an olefin, an aromatic compound, or a mixture of any two or more thereof.

[0023] In some embodiments, the method includes processing and refining one or more of the first hydrocarbon product, the second hydrocarbon product, the first plastic residue, or the second plastic residue in a steam cracker, a hydrocracker, a fluid catalytic cracker, a deep catalytic cracker, a high severity fluid catalytic cracker, a steam reformer, a liquid cracked gas plant, or an aromatics recovery unit.

[0024] In some embodiments, the size of the first conical spouted bed reactor stage is the same as the size of the second conical spouted bed reactor stage. In some embodiments, the method is performed continuously. In some embodiments, the plastic feedstock comprises waste plastic. In some embodiments, separating at least a portion of the first product vapor from the drive gas and the first residual plastic to generate a first product stream comprising the first product vapor occurs in the first conical spouted bed reactor stage.

[0025] In some embodiments, the first product stream is removed from the first conical spouted bed reactor stage immediately upon formation. In some embodiments, separating at least a portion of the second product vapor from the drive gas and the second residual plastic to generate a second product stream comprising the second product vapor occurs in a second conical spouted bed reactor stage. In some embodiments, the second product stream is removed from the second conical spouted bed reactor stage immediately upon formation.

[0026] In some embodiments, the average gas phase residence time in the second conical spouted bed reactor stage is from about 0.2 seconds to about 60 seconds, or preferably from about 0.5 seconds to about 5 seconds. In some embodiments, the first conical spouted bed reactor stage and the first conical spouted bed reactor stage operate in the fast pyrolysis regime. In some embodiments, the driving gas contains less than 1.0 wt. % oxygen, or more preferably less than 0.1 wt. % oxygen. [Brief description of the drawings]

[0027] [Figure 1] 1 is a graph of the fractional conversion of HDPE, LDPE, and PP at 500° C. and 550° C. as a function of time according to an example. [Diagram 2] 1 is a graph of residence time distribution for continuous flows into and out of a series of well-mixed reactors, according to an embodiment. [Diagram 3] 1 is a graph of the total unconverted HDPE from each residence time interval in a series of well-mixed reactors at 550° C. according to an example. [Figure 4] 1 is a graph of the total unconverted PP from each residence time interval in a series of well-mixed reactors at 550° C. according to an example. [Diagram 5] FIG. 1 is a schematic diagram of two reactor vessels in series according to an exemplary embodiment. [Figure 6] FIG. 1 is a schematic diagram of a single reactor vessel configuration housing three reaction chambers separated by baffles, in the left image all chambers are at the same height and in the right image the chambers have tapered heights, according to various embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Various embodiments are described below. It should be noted that the specific embodiments are not intended as an exhaustive description or as a limitation to the broader aspects discussed herein. An aspect described in conjunction with a specific embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiment.

[0029] As used herein, "about" will be understood by one of ordinary skill in the art and will vary to some extent depending on the context in which it is used. If there are uses of the term that are not clear to persons of ordinary skill in the art, given the context in which it is used, "about" will mean up to plus or minus 10% of the particular term.

[0030] "A" and "an" and "the" and similar referents in the context of describing elements (particularly in the context of the claims below) should be construed to cover both the singular and the plural, unless otherwise indicated herein or the content clearly contradicts. The recitation of ranges of values ​​herein is merely intended to serve as a shorthand method of individually referring to each separate value within the range, unless otherwise indicated herein, and each separate value is incorporated herein as if it were individually recited herein. All methods described herein may be performed in any suitable order, unless otherwise indicated herein or the content clearly contradicts otherwise. The use of any and all examples or exemplary language (e.g., "etc.") provided herein is intended merely to better illustrate the embodiments, and does not impose limitations on the scope of the claims, unless otherwise specified. No language in this specification should be construed as indicating any non-claimed element as essential.

[0031] A system for converting plastic feedstocks into valuable hydrocarbon products. Disclosed herein is a system for converting plastic feedstocks to more valuable hydrocarbon feedstocks, such as olefins and aromatics, at high yields. The purpose of the system is to provide a continuous process for pyrolysis of plastic waste in a spouted bed reactor. The system disclosed herein features a novel reactor design with two or more spouted beds in series to continuously convert plastics to lower molecular weight products while continuously circulating catalyst between the reactor and regenerator to burn off coke. It has been found that the use of a conical spouted bed reactor minimizes unconverted plastics circulating from the reactor to the regenerator, increasing the overall efficiency of the process. The use of multiple reactors in series also increases the uniformity of plastic residence time in the system and substantially eliminates bypass of plastics to the regenerator.

[0032] The system includes a catalyst regenerator, a feeder containing a plastic feedstock, and at least two conical spouted bed reactor stages in fluid communication with each other, with the first reactor stage also in fluid communication with the feeder. The conical spouted bed reactor stage includes a base, a frustoconical portion, and a cylindrical portion extending from the base. Inlets for the plastic feedstock and catalyst are typically provided near the top of the reactor stage. An inlet for a drive gas is provided at the bottom of the reactor stage.

[0033] Although the present disclosure focuses on systems with two or three reactor stages, this is done for the sake of simplicity and brevity of the present disclosure and should not be construed as limiting the system to only two or three reactor stages. In some of these embodiments, a fourth conical spouted bed reactor stage is used that is in fluid communication with the third conical spouted bed reactor stage. In some embodiments, a greater number of reactor stages are used. For example, 5, 6, 7, 8, 9, or 10 reactor stages can be used.

[0034] During operation of the system, a plastic feedstock is fed to a reactor stage containing a catalyst in a catalyst bed. In some embodiments, the catalyst is also fed to the reactor stage. In some embodiments, the catalyst is fed separately from the plastic feedstock. In other embodiments, the plastic feedstock and catalyst are fed together.

[0035] The drive gas is supplied to the reactor stage by a gas supply system. The fluidizing gas forms a cylindrical path, or spout, through the catalyst bed. The catalyst entrained by the gas flowing through the spout is propelled above the surface of the catalyst bed and settles back to the fountain shape. The catalyst travels down the annular region and returns to the bottom of the conical bed, thus completing the cycle. The rapid circulation of catalyst and reactants ensures good mixing in the reactor. The fountain is a region of low catalyst density called the dilute phase, and the annulus is a region of high catalyst density called the dense phase. In the absence of a draft tube, some of the gas flows around the spout and through the annular region. Unreacted plastic feedstock (or plastic feedstock particles that are not fully converted to product) can proceed from one reactor stage to the subsequent stage. If more than two stages are used, the unreacted plastic feedstock in the reactor stage may flow into each subsequent stage until the final stage is reached. Catalyst may also flow from one stage to the subsequent stage. Operating reactor stages in series has many advantages, including, but not limited to, increased conversion of the feedstock to products, increased residence time of the feedstock in the reactor, and reduced carryover of the feedstock to the catalyst regenerator unit.

[0036] In some embodiments, in the operation of the system, the transfer of unreacted plastic feedstock and catalyst from one reactor stage to the next may be facilitated by pipes connecting the two reactor stages. The transfer of materials between the stages is driven in part by the flow of gases through the system, such as a drive gas supplied to each reactor stage. It is contemplated that the flow between the reactors may be further facilitated by locating the subsequent reactor stage at a lower elevation than the preceding reactor stage, such that the movement of materials from one stage to the next may be at least in part driven by gravity. The pipes connecting the stages may be vented with an inert gas, such as nitrogen, such that the transfer of materials is pneumatically driven. Venting may be used when the reactor stages are located at different elevations or when the reactor stages are at the same elevation. Other means of facilitating the transfer of materials between the reactor stages are also contemplated, such as the use of an auger or similar physical means.

[0037] In some embodiments, each reactor stage is housed within the same reactor vessel. In other embodiments, multiple stages are housed within a single reactor vessel. For example, in a system including three reactor stages, each reactor stage may be housed within a single vessel. Alternatively, each reactor stage may be housed in a separate vessel. Alternatively, one reactor stage may be housed in a vessel separate from the other two stages (e.g., the first reactor stage is housed in a vessel separate from the vessel housing the second and third stages).

[0038] In embodiments in which multiple reactor stages are housed within a single vessel, baffles can be used to separate the reactor stages from one another. The baffles may be positioned to provide a passageway between the reactor stages. For example, a baffle may be positioned between two stages such that there is a passageway at the top of one of the stages, at the bottom of one of the stages, or on the side of one of the stages. Combinations are also possible, and it should be understood that the top of one reactor stage may not correspond to the top of the next reactor stage due to different positions of the reactor stages within the reactor vessel.

[0039] As previously mentioned, a catalyst regenerator is used in the system. During operation, the catalyst used to promote the pyrolysis of the plastic feedstock may be deactivated by coke buildup. The catalyst is continuously cycled between the reactor stage and the regenerator. In the regenerator, the catalyst is exposed to high temperatures and oxygen or air to burn off the built-up coke, thereby regenerating the catalyst. In some embodiments, the deactivated catalyst is exposed to air. The hot catalyst is then returned to the reactor stage. The hot catalyst can be fed to any of the reactor stages. For example, the hot catalyst can be fed to the first reactor stage or the second reactor stage, or to each reactor stage.

[0040] The catalyst feed can also be used to maintain the temperature in the reactor stage by providing the heat required for the pyrolysis of the plastic feedstock. Since the pyrolysis of the plastic feedstock is an endothermic reaction, additional heat input is required. This heat can be supplemented by a high temperature catalyst. In some embodiments, the catalyst flow rate to the reactor can be adjusted in-situ to maintain the reactor stage at a predetermined temperature set point. For example, if the temperature in a reactor stage falls below a low temperature set point, the flow rate of high temperature catalyst from the regenerator to that reactor stage can be increased to increase the temperature in the reactor stage. Conversely, if the temperature in a reactor stage rises above a high temperature set point, the flow rate of high temperature catalyst from the regenerator to that reactor stage can be decreased to decrease the temperature in the reactor stage.

[0041] In some embodiments, the reactor stage includes a draft tube to direct the flow of the driving gas and induce enhanced mixing of the catalyst and the plastic feedstock. In some embodiments, the draft tube extends from the bottom of the reactor stage toward the top of the reactor stage. In some embodiments, the draft tube may be concentrically disposed with the driving gas inlet. The draft tube comprises a cylindrical tube having an outer diameter smaller than the inner diameter of the bottom of the associated conical spouted bed reactor stage. In some embodiments, the ratio of the draft tube diameter to the driving gas inlet diameter is about 1:1 to about 2:1. The draft tube may include at least one opening extending upward from the bottom of the draft tube through which the catalyst material may pass. In some embodiments, the draft tube is an open-sided draft tube. In other embodiments, the draft tube is non-porous. The driving gas flowing through the draft tube creates an area of ​​negative pressure at the bottom of the tube, which draws the catalyst from the annular region through the slots and propels it to the upper side of the draft tube. The catalyst contained within the reactor stage may thereby become entrained in the driving gas, allowing the materials to mix. The draft tube directs the gas through the jets such that less gas travels through the annulus compared to a conventional spouted bed reactor, and therefore the minimum jet velocity in the presence of a draft tube is much lower than in the absence of a draft tube.

[0042] In some embodiments, the reactor stage includes a containment vessel that extends from the top to the bottom of the reactor stage. In some embodiments, the containment vessel is a cylindrical tube that extends from the top to the bottom of the reactor stage. The containment vessel may be arranged concentrically with the plastic feedstock inlet at the top of the reactor. The containment vessel, which is closed at the top, changes the direction of the ejected catalyst downward. The containment vessel acts to reduce the volume available for the gas and vapor phase in the reactor stage, so that the feedstock from the top of the reactor mixes more quickly with the catalyst material ejected into the containment vessel volume. This results in more turbulent mixing of the catalyst and plastic, more heat transfer, and melting of the plastic feedstock, which distributes the molten particles on the catalyst particles.

[0043] The use of a conical spouted bed reactor allows for the use of plastic feedstocks with diameters much larger than those traditionally used. One skilled in the art would expect the plastic feedstock to be processed to have an average nominal particle size of 1 mm or less. Processing of the plastic feedstock may include melting the plastic and cutting the extruded material to the desired size. In the present system disclosed herein, particle sizes of about 1 mm to 20 mm may be used. Preferably, the plastic feedstock has an average nominal particle size of about 8 mm to 10 mm.

[0044] In some embodiments, the reactor stages operate in a pyrolysis regime. In some embodiments, the reactor stages operate in a "fast pyrolysis" regime where the reactor stages operate at pyrolysis temperatures and the gas phase has a residence time of 1 second or less. In some embodiments, the reactor stages operate at temperatures between about 300°C and about 650°C, or more preferably between about 450°C and about 600°C, or most preferably between about 480°C and about 550°C. The reactor stages may all operate at the same temperature, or each reactor stage may operate at a different temperature depending on the conversion demands of the system or to tailor product selectivities.

[0045] In some embodiments, the drive gas is an inert gas. In some embodiments, the drive gas is nitrogen, argon, steam, or a combination thereof. In some embodiments, the drive gas is less than 1.0% oxygen by weight, or more preferably, less than 0.1% oxygen by weight. In some embodiments, the drive gas is substantially free of oxygen.

[0046] To reduce product cracking, the system may include means for separating and collecting the products as soon as they are produced. Product vapors may be separated and collected from each reactor. This prevents the product vapors from traveling through each subsequent reactor stage. In some embodiments, the system also includes other equipment for processing the hydrocarbon products as they are produced. In some embodiments, the system includes a set of cyclone separators in fluid communication with at least one of the reactor stages. In some of these embodiments, a set of cyclone separators is connected to each reactor stage such that a single set of cyclone separators can contribute to the system. In other embodiments, each reactor stage has a separate set of cyclone separators. In other embodiments, the system includes at least one of a steam cracker, a hydrocracker, a fluid catalytic cracker, a deep catalytic cracker, a high severity fluid catalytic cracker, a steam reformer, a liquid cracked gas plant, or an aromatics recovery unit.

[0047] Process for converting plastic feedstocks into valuable hydrocarbon products Also disclosed herein is a second aspect of a method for producing valuable hydrocarbon products from plastics, the method comprising the steps of feeding a plastic feedstock and a drive gas to a first conical spouted bed reactor stage containing a catalyst to produce a first product vapor and a first residual plastic, separating at least a portion of the first product vapor from the drive gas and the first residual plastic to produce a first product stream comprising the first product vapor, feeding the first residual plastic from the first conical spouted bed reactor stage to a second conical spouted bed reactor stage containing a catalyst to produce a second product vapor and a second residual plastic, and separating at least a portion of the second product vapor from the drive gas and the second residual plastic to produce a second product stream comprising the second product vapor. In some embodiments, the method also includes feeding the second residual plastic from the second conical spouted bed reactor stage to a third conical spouted bed reactor stage containing a catalyst to produce a third product vapor and a third residual plastic, and separating the third product vapor, the drive gas, and the third residual plastic to produce a third product stream comprising the third product vapor. In some of these embodiments, the method also includes feeding the third residual plastic from the third conical spouted bed reactor stage to a fourth conical spouted bed reactor stage containing a catalyst to produce a fourth product vapor and a residue, and separating the fourth product vapor, the drive gas, and the residue to produce a fourth product stream comprising the fourth product vapor. Additional reactor stages may be used as necessary to achieve the desired overall conversion of the plastic feedstock.

[0048] The reactor stages used in the method may be contained within a single reactor vessel or may be distributed among multiple reactor vessels. For example, in an embodiment using three reactor stages, all three stages are contained within a single reactor vessel. In another embodiment using three reactor stages, each reactor stage is contained within a separate vessel. In another embodiment using three reactor stages, the first and second reactor stages are contained within a reactor vessel and the third stage is contained within a separate reactor vessel. In another embodiment using three reactor stages, the first stage is contained within one reactor vessel and the second and third stages are contained within a separate reactor vessel.

[0049] The method is applicable to several different plastic feedstocks. The feedstock may include high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, or a mixture of any two or more thereof. In some embodiments, the plastic feedstock is derived from plastic waste. In some embodiments, the plastic feedstock is primarily plastic waste.

[0050] The plastic feedstock is generally pre-processed to achieve an average nominal particle size of about 1 mm to about 20 mm, or more preferably about 8 mm to about 10 mm. In some embodiments, the plastic feedstock has an average nominal particle size of about 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, or 20 mm.

[0051] The reactor stages used in this method can be operated at pyrolysis or fast pyrolysis conditions. To achieve pyrolysis conditions, the temperature of the reactor stage is increased to above about 300° C. to limit the amount of oxygen available to the system. In some embodiments, the reactor stage operates at a temperature between about 300° C. and about 650° C. In some embodiments, the reactor stage operates at a temperature between about 450° C. and about 600° C. In some embodiments, the reactor stage operates at a temperature between about 480° C. and about 550° C.

[0052] The reactor in this process is operated so that each reactor stage has an average gas phase residence time of from about 0.2 seconds to about 60 seconds, or preferably from about 0.5 seconds to about 5 seconds.

[0053] Each reactor stage contains a catalyst for facilitating the pyrolysis of the plastic feedstock. The ratio of the mass of catalyst to the mass of plastic in each stage varies from stage to stage. In some stages, the ratio of the mass of catalyst to the mass of fuel ranges from about 5:1 to about 15:1, or more preferably from about 8:1 to about 10:1. In other stages, the ratio of the mass of catalyst to the mass of fuel ranges from about 15:1 to about 40:1, or more preferably from about 25:1 to about 35:1. The method may include transferring the catalyst from one reactor to another reactor stage, thereby allowing the catalyst to flow through the reactor stages and ultimately to a regenerator. In some embodiments, the method includes transferring at least a portion of the catalyst from a first conical spouted bed reactor stage to a second conical spouted bed reactor stage. In other embodiments, the method includes transferring at least a portion of the catalyst from a second conical spouted bed reactor stage to a third conical spouted bed reactor stage. Or, generally speaking, in some embodiments, the method includes transferring at least a portion of the catalyst from a given conical spouted bed reactor stage to a subsequent conical spouted bed reactor stage. The transfer of the catalyst from one stage to the next may be driven by a flow of a motive gas, a flow of air or aeration gas, gravity, or a combination thereof.

[0054] As a catalyst is used to process plastic feedstock, the catalyst may become deactivated due to the accumulation of coke on the surface of the catalyst. Regeneration of the catalyst can be accomplished by burning off the coke in a regenerator. In some embodiments, the method includes a step of regenerating the catalyst. In some embodiments, the catalyst is regenerated in the regenerator by exposing the catalyst to high temperature and a source of oxygen. In some embodiments, the source of oxygen is air. Regeneration of the catalyst is an oxidative and exothermic reaction.

[0055] Because the plastic pyrolysis process is endothermic, heat must be applied to the reactor stages to maintain a sufficiently high temperature. The catalyst exits the regenerator at a very high temperature. The temperature within the reactor stages can be controlled by adjusting the rate of regenerated catalyst returned to the reactor stages. In some embodiments, regenerated catalyst is fed only to the first reactor stage. In other embodiments, regenerated catalyst is fed to each reactor stage. In some embodiments, the regenerated feed rate can be adjusted based on a predetermined target temperature. For example, if the temperature inside a particular stage rises above an upper temperature limit, the feed rate of hot catalyst to that stage can be decreased. And, if the temperature in a particular reactor stage falls below a lower temperature limit, the feed rate of hot catalyst to that reactor stage can be increased.

[0056] In some embodiments, the first and second hydrocarbon products are C1-C 12 Saturated hydrocarbons, C1-C 12 In some embodiments, the hydrocarbon products include olefins, aromatics, or mixtures of any two or more thereof. The products from one reactor stage may be the same or different from the products from another reactor stage. In some embodiments, the hydrocarbon products include olefins, aromatics, or mixtures of any two or more thereof.

[0057] The product stream from the method is collected for further processing and purification. The product vapor is preferably removed as soon as it is formed in the reactor stage. In some embodiments, separation of the product stream from other materials in the reactor stage begins within the reactor stage itself. This can be accomplished by using a containment vessel within the reactor stage, as a non-limiting example. In some embodiments using two reactor stages, the first and second product streams are collected in separate vessels. In some embodiments using two reactor stages, the first and second product streams are combined and conveyed to a single set of cyclone separators. In some embodiments, the plastic pyrolysis process is integrated with a refinery, which can receive the recovered product stream and refine it in an existing FCC gas plant or further process it via hydrotreating or catalytic cracking to produce transportation fuels or petrochemicals. Hydrotreating can include fixed bed or ebullated bed hydrotreating or hydrocracking. Catalytic cracking can include fluid catalytic cracking (FCC), deep catalytic cracking (DCC), and high severity fluid catalytic cracking (HSFCC).

[0058] In another embodiment of the invention, the plastic pyrolysis process is integrated with a petrochemical plant, which can receive the recovered products and further convert them via a gas or liquid steam cracking process to increase the production of petrochemical products such as ethylene, propylene, butenes, and butadiene.

[0059] The invention having thus been generally described will be more readily understood with reference to the following examples, which are provided by way of illustration and are not intended to be limiting of the invention. EXAMPLES

[0060] Example 1. The conversion of HDPE, LDPE, and PP at 500°C and 550°C is shown in Figure 1. At 500°C, the reaction does not reach 100% conversion even after 600 seconds. At 550°C, the reaction reaches over 99% conversion in 120 seconds for HDPE and LDPE, and 180 seconds for PP. The reaction rates used in the calculations were determined experimentally.

[0061] Example 2. Calculated residence time distributions for 1, 2, 3, and 4 reactors in series are shown in Figure 2. In all four cases, the average residence time is 360 seconds. With only one reactor, a significant portion of the plastic leaves the reactor in less than 180 seconds, before the pyrolysis reaction is complete. Some material even leaves the reactor immediately after entering. This problem is eliminated by using two or more reactors in series. As the number of reactors in series increases, the residence time distribution narrows and the percentage of unconverted plastic leaving the reactor decreases. The reaction kinetics in Figure 1 can be combined with the residence time distribution in Figure 2 to determine the percentage of unconverted plastic at each residence time increment. The total percentage of unconverted plastic can be determined by integrating over the entire residence time distribution. Results for HDPE and PP at a reaction temperature of 550 °C are shown in Figures 3 and 4. In a single reactor, unconverted PE and PP represent 6.0% and 9.8% of the total plastic, respectively. If unconverted plastics entrained in the catalyst are recycled to the regenerator, the coke yield will increase and the yield of valuable products will decrease. The excess coke will also increase the regenerator temperature and cause a decrease in the catalyst circulation rate of the heat balance unit, which can further reduce the conversion. Furthermore, for units that do not have sufficient catalyst cooling capacity, it will be necessary to reduce the feed throughput as the regenerator temperature can reach the metallurgical limits of the vessel.

[0062] With two reactors in series, the unconverted PE and PP are rapidly reduced to 1.3% and 3.2%, respectively. With three reactors in series, the unconverted PE and PP are further reduced to 0.42% and 1.5%, respectively, and with four reactors in series, to 0.17% and 0.86%, respectively. This example clearly shows the advantage of using two or more reactors in series for plastic pyrolysis.

[0063] Example 3. Reactors in series can be achieved by having separate reactor vessels or a single vessel with multiple chambers or compartments. A schematic diagram of two spouted bed reactor vessels is shown in Figure 5. Plastic is fed into reactor 1 along with hot catalyst from the regenerator. The reaction product is removed from reactor 1. Spent catalyst and unreacted plastic flow from reactor 1 to reactor 2. Additional hot catalyst from the regenerator may be added to reactor 2 to control the reaction temperature. Gas for fluidization or blowing is fed separately to each vessel. The proportion of unreacted plastic in the reactor is very low, as shown in Figures 3 and 4. Spent catalyst from reactor 2 is conveyed to the regenerator by air pressure. The reaction product from reactor 2 is combined with the product from reactor 1 and sent to product recovery and purification.

[0064] Example 4. Two configurations of a single vessel housing three interconnected spouted bed reaction chambers are shown in Figure 6. For ease of construction, the chambers may be inverted pyramid shaped with straight sides. In the first configuration, the chambers are placed at the same height, with a baffle installed in the last chamber to control the level of catalyst. The catalyst flows over the baffle from one chamber to the next. In this configuration, the level of the catalyst bed, and therefore the amount of catalyst, decreases from the first chamber to the last chamber. In the second configuration, the chambers are staggered so that each chamber is at a lower height than the preceding chamber, allowing the catalyst to flow by gravity. In this configuration, the amount of catalyst may be the same in each chamber.

[0065] For both arrangements, gas for fluidization or blowing is fed separately to each chamber. Plastic is fed to the first chamber. Catalyst and unconverted plastic flow from one chamber to the next through openings, which may be at the level of the catalyst bed, below the level of the catalyst bed, or at the side of the catalyst bed. The chambers may be separated by baffles that are either below, above, or both below and above the surface of the catalyst bed. To control the temperature profile, the hot regenerated catalyst may be directed all to the first chamber or distributed to all of the chambers. Product vapors are collected from each chamber and combined downstream and sent to product recovery and purification.

[0066] Paragraph 1. A system for converting plastics into low molecular weight products, comprising: A catalyst regenerator; a feeder for receiving the plastic raw material; a first conical spouted bed reactor stage in fluid communication with the catalyst regenerator and in fluid communication with the feeder; a second conical spouted bed reactor stage in fluid communication with the first conical spouted bed reactor stage; A system that is equipped with the above.

[0067] Paragraph 2. a first reactor vessel housing the first conical spouted bed reactor stage; a second reactor vessel housing the second conical spouted bed reactor stage; and Further equipped with 2. The system of paragraph 1, wherein the first reactor vessel and the second reactor vessel are fluidly connected with at least one pipe configured to deliver a stream of catalyst and unreacted plastic feedstock from the first reactor vessel to the second reactor vessel.

[0068] Paragraph 3. The system of Paragraph 2, wherein the second reactor vessel is at a lower elevation than the first reactor vessel.

[0069] Paragraph 4. The system of Paragraph 2, wherein the piping is vented such that the flow of catalyst and unreacted plastic feedstock from the first reactor vessel to the second reactor vessel is pneumatically driven.

[0070] Paragraph 5. The system of any one of Paragraphs 1-4, wherein the first conical spouted bed reactor stage and the second conical spouted bed reactor stage are contained within a single reactor vessel, and the first conical spouted bed reactor stage and the second conical spouted bed reactor stage are at least partially separated by a baffle.

[0071] Paragraph 6. The system of Paragraph 5, wherein the baffle defines at least one opening between the first conical spouted bed reactor stage and the second conical spouted bed reactor stage at a top, bottom, or at least one side of the first conical spouted bed reactor stage.

[0072] Paragraph 7. The system of Paragraph 5, wherein the first conical spouted bed reactor stage and the second conical spouted bed reactor stage are at different relative heights.

[0073] Paragraph 8. The system of any one of Paragraphs 1-7, wherein the first conical spouted bed reactor stage is configured to receive catalyst from the catalyst regenerator.

[0074] Paragraph 9. The system of any one of Paragraphs 1-8, wherein the second conical spouted bed reactor stage is in fluid communication with the catalyst regenerator and configured to receive catalyst from the catalyst regenerator.

[0075] Paragraph 10. The system of Paragraph 8, wherein the flow of catalyst from the catalyst regenerator to the first conical spouted bed reactor stage is adjustable in response to the temperature in the first conical spouted bed reactor stage falling below a predetermined temperature set point.

[0076] Paragraph 11. The system of any one of Paragraphs 1 to 10, wherein the first conical spouted bed reactor stage operates in the pyrolysis regime.

[0077] Paragraph 12. The system of Paragraph 9, wherein the flow of catalyst from the catalyst regenerator to the second conical spouted bed reactor stage is adjustable in response to the temperature in the second conical spouted bed reactor stage falling below a predetermined temperature set point.

[0078] Paragraph 13. The system of any one of Paragraphs 1-12, further comprising a draft tube extending from a bottom of the first conical spouted bed reactor stage toward a top of the first conical spouted bed reactor stage, the draft tube comprising a cylindrical tube having an outer diameter smaller than an inner diameter of the bottom of the first conical spouted bed reactor stage and at least one opening extending upwardly from the bottom of the draft tube.

[0079] Paragraph 14. The system of any one of Paragraphs 1-13, further comprising a containment vessel extending from a top of the first conical spouted bed reactor stage toward a bottom of the first conical spouted bed reactor stage, the containment vessel comprising a cylindrical tube having an outer diameter smaller than an inner diameter of the top of the first conical spouted bed reactor stage.

[0080] Paragraph 15. The system of any one of Paragraphs 1-14, further comprising a third conical spouted bed reactor stage in fluid communication with said second conical spouted bed reactor stage.

[0081] Paragraph 16. The system of any one of Paragraphs 1 to 15, wherein during operation, the first conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C.

[0082] Paragraph 17. The system of any one of Paragraphs 1-16, wherein during operation, the second conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C.

[0083] Paragraph 18. The system of any one of Paragraphs 1-17, further comprising a gas supply system in fluid communication with said first conical spouted bed reactor stage and said second conical spouted bed reactor stage, said gas supply system configured to supply a drive gas to said first conical spouted bed reactor stage and said second conical spouted bed reactor stage.

[0084] Paragraph 19. The system of Paragraph 18, wherein the driving gas contains less than 1.0 wt. % oxygen, or more preferably, less than 0.1 wt. % oxygen.

[0085] Paragraph 20. The system of any one of Paragraphs 1-19, further comprising a set of separating cyclones in fluid communication with said first conical spouted bed reactor stage and said second conical spouted bed reactor stage.

[0086] Paragraph 21. A method for producing hydrocarbon products from plastics, comprising: supplying the plastic feedstock and a drive gas to a first conical spouted bed reactor stage containing a catalyst to produce a first product vapor and a first residual plastic; separating at least a portion of the first product vapor from the drive gas and the first residual plastics to produce a first product stream comprising the first product vapor; feeding the first residual plastic from the first conical spouted bed reactor stage to a second conical spouted bed reactor stage containing a catalyst to produce a second product vapor and a second residual plastic; separating at least a portion of the second product vapor from the drive gas and the second residual plastic to produce a second product stream comprising the second product vapor; A method comprising:

[0087] Paragraph 22. The method of Paragraph 21, further comprising transferring at least a portion of said catalyst from said first conical spouted bed reactor stage to said second conical spouted bed reactor stage.

[0088] Paragraph 23. The method of any one of Paragraphs 21-22, further comprising transferring at least a portion of the catalyst from the second conical spouted bed reactor stage to a regenerator.

[0089] Paragraph 24. The method of any one of Paragraphs 21-23, further comprising providing catalyst from said regenerator to said first conical spouted bed reactor stage.

[0090] Paragraph 25. The method of Paragraph 23, further comprising providing catalyst from said regenerator to said second conical spouted bed reactor stage.

[0091] Paragraph 26. The method of any one of Paragraphs 22 to 25, wherein the transfer of a portion of the catalyst from the first conical spouted bed reactor stage to a second conical spouted bed reactor stage is driven, at least in part, by a flow of a driving gas.

[0092] Paragraph 27. The method of any one of Paragraphs 23-26, wherein the transport of a portion of the catalyst from the second conical spouted bed reactor stage to the regenerator is driven, at least in part, by a flow of a drive gas.

[0093] Paragraph 28. The method of any one of Paragraphs 21 to 27, wherein the first conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C.

[0094] Paragraph 29. The method of Paragraph 28, wherein the temperature of said first conical spouted bed reactor stage is controlled in part by supplying hot catalyst from said regenerator to said first conical spouted bed reactor stage.

[0095] Paragraph 30. The method of any one of Paragraphs 21 to 29, wherein the second conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C.

[0096] Paragraph 31. The method of Paragraph 29, wherein the temperature of said second conical spouted bed reactor stage is controlled in part by supplying hot catalyst from said regenerator to said second conical spouted bed reactor stage.

[0097] Paragraph 32. The method of any one of Paragraphs 21 to 31, wherein the plastic feedstock is first chopped to a nominal size of about 1 mm to about 20 mm or about 8 mm to about 10 mm before being fed to the first conical spouted bed reactor stage.

[0098] Paragraph 33. The method of any one of Paragraphs 21 to 31, wherein the first conical spouted bed reactor stage and the second conical spouted bed reactor stage are both contained within a single reactor vessel.

[0099] Paragraph 34. The method of any one of Paragraphs 21-31, further comprising: feeding the second residual plastic from the second conical spouted bed reactor stage to a third conical spouted bed reactor stage containing a catalyst to produce a third product vapor and a residue; and separating the third product vapor, the drive gas, and the residue to produce a third product stream comprising the third product vapor.

[0100] Paragraph 35. The method of any one of Paragraphs 21-34, further comprising directing the first product stream and the second product stream into a cyclone separator.

[0101] Paragraph 36. The method of Paragraph 35, wherein the first product stream and the second product stream are combined before being directed to the set of cyclone separators.

[0102] Paragraph 37. The method of any one of Paragraphs 21 to 36, further comprising collecting the first product stream and the second product stream in a separation vessel.

[0103] Paragraph 38. The method of any one of Paragraphs 21 to 37, wherein the plastic raw material comprises high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, or a mixture of any two or more thereof.

[0104] Paragraph 39. The first hydrocarbon product and the second hydrocarbon product are selected from the group consisting of C1 to C 12 Saturated hydrocarbons, C1-C 12 39. The method of any one of paragraphs 21 to 38, wherein the first hydrocarbon product and the second hydrocarbon product comprise an unsaturated hydrocarbon, or a mixture of any two or more thereof, and wherein the first hydrocarbon product and the second hydrocarbon product can be the same or different.

[0105] Paragraph 40. The process of any one of Paragraphs 21 to 39, wherein the hydrocarbon product comprises olefins, aromatics, or a mixture of any two or more thereof.

[0106] Paragraph 41. The method of any one of Paragraphs 21 to 40, further comprising processing and purifying one or more of the first hydrocarbon product, the second hydrocarbon product, the first plastic residue, or the second plastic residue in a steam cracker, a hydrocracker, a fluid catalytic cracker, a deep catalytic cracker, a high severity fluid catalytic cracker, a steam reformer, a liquid cracked gas plant, or an aromatics recovery unit.

[0107] Paragraph 42. The method of any one of Paragraphs 21 to 41, wherein the size of the first conical spouted bed reactor stage is the same as the size of the second conical spouted bed reactor stage.

[0108] Paragraph 43. The method of any one of Paragraphs 21 to 42, which is carried out sequentially.

[0109] Paragraph 44. The method of any one of Paragraphs 21 to 43, wherein the plastic raw material comprises waste plastic.

[0110] Paragraph 45. The method of any one of Paragraphs 21 to 44, wherein separating at least a portion of the first product vapor from the drive gas and the first residual plastic to produce a first product stream comprising the first product vapor occurs in the first conical spouted bed reactor stage.

[0111] Paragraph 46. The method of any one of Paragraphs 21 to 45, wherein the first product stream is removed from the first conical spouted bed reactor stage immediately upon formation.

[0112] Paragraph 47. The method of any one of Paragraphs 21 to 46, wherein separating at least a portion of the second product vapor from the drive gas and the second residual plastic to produce a second product stream comprising the second product vapor occurs in the second conical spouted bed reactor stage.

[0113] Paragraph 48. The method of any one of Paragraphs 21 to 47, wherein the second product stream is removed from the second conical spouted bed reactor stage immediately upon formation.

[0114] Paragraph 49. The method of any one of Paragraphs 21 to 48, wherein the average gas phase residence time in said first conical spouted bed reactor stage is from about 0.2 seconds to about 60 seconds, or preferably from about 0.5 seconds to about 5 seconds.

[0115] Paragraph 50. The method of any one of Paragraphs 21 to 49, wherein the average gas phase residence time in said second conical spouted bed reactor stage is from about 0.2 seconds to about 60 seconds, or preferably from about 0.5 seconds to about 5 seconds.

[0116] Paragraph 51. The method of any one of Paragraphs 21 to 50, wherein the drive gas contains less than 1.0 wt. % oxygen, or more preferably, less than 0.1 wt. % oxygen.

[0117] Paragraph 52. The method of any one of Paragraphs 21 to 51, wherein said first conical spouted bed reactor stage and said first conical spouted bed reactor stage operate in a fast pyrolysis regime.

[0118] While certain embodiments have been illustrated and described, it should be understood that changes and modifications may be made therein by those skilled in the art without departing from the technology in its broader aspects as defined in the following claims.

[0119] The embodiments illustratively described herein may be suitably practiced in the absence of any element(s), limitation(s) not specifically disclosed herein. Thus, for example, terms such as "comprising", "including", "containing" and the like should be read expansively and without limitation. In addition, the terms and expressions used herein are used as terms of description rather than limitation, and in the use of such terms and expressions, there is no intention to exclude any equivalents of the shown and described features or portions thereof, but it is recognized that various modifications are possible within the scope of the claimed technology. In addition, the phrase "consisting essentially of" will be understood to include those elements specifically recited, as well as those additional elements that do not materially affect the basic and novel features of the claimed technology. The phrase "consisting of" excludes any elements not specified.

[0120] The present disclosure is not limited with respect to the specific embodiments described in this application. As will be apparent to those skilled in the art, many modifications and variations can be made without departing from the spirit and scope of the present invention. In addition to those enumerated herein, functionally equivalent methods and compositions within the scope of the present disclosure will be apparent to those skilled in the art from the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that the present disclosure is not limited to specific methods, reagents, compounds, compositions, or biological systems, which may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

[0121] Additionally, when features or aspects of the disclosure are described in terms of a Markush group, one of skill in the art will recognize that the disclosure is also thereby described in terms of any individual members or subgroups of members of the Markush group.

[0122] As will be understood by those skilled in the art, for all and all purposes, especially in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges. Any recited range can be easily recognized as fully describing and allowing the same range to be subdivided into at least two, three, four, five, ten, etc. As a non-limiting example, each range discussed herein can be easily subdivided into a lower third, a middle third, and an upper third, etc. Also, as will be understood by those skilled in the art, all terms such as "up to," "at least," "greater than," "less than," etc. refer to a range that includes the recited number and can then be subdivided into the subranges discussed above. Finally, as will be understood by those skilled in the art, a range includes each individual member.

[0123] All publications, patent applications, issued patents, and other documents referenced herein are incorporated by reference as if each individual publication, patent application, issued patent, or other document was specifically and individually indicated to be incorporated by reference in its entirety. Definitions contained in the descriptions incorporated by reference are excluded to the extent that they contradict definitions in this disclosure.

[0124] Other embodiments are within the scope of the following claims.

Claims

1. 1. A system for converting plastics into low molecular weight products, comprising: a catalyst regenerator; a feeder for receiving plastic raw materials; a first conical spouted bed reactor stage in fluid communication with the catalyst regenerator and in fluid communication with the feeder; a second conical spouted bed reactor stage in fluid communication with the first conical spouted bed reactor stage; A system that includes:

2. a first reactor vessel containing the first conical spouted bed reactor stage; a second reactor vessel containing the second conical spouted bed reactor stage; Furthermore, 10. The system of claim 1, wherein the first reactor vessel and the second reactor vessel are fluidly connected with at least one pipe configured to transmit a stream of catalyst and unreacted plastic feedstock from the first reactor vessel to the second reactor vessel.

3. 3. The system of claim 2, wherein the second reactor vessel is at a lower elevation than the first reactor vessel and / or the pipe is vented such that the flow of catalyst and unreacted plastic feedstock from the first reactor vessel to the second reactor vessel is pneumatically driven.

4. 10. The system of claim 1, wherein the first conical spouted bed reactor stage and the second conical spouted bed reactor stage are contained within a single reactor vessel, and the first conical spouted bed reactor stage and the second conical spouted bed reactor stage are at least partially separated by a baffle.

5. 5. The system of claim 4, wherein the baffle defines at least one opening between the first and second conical spouted bed reactor stages at the top, bottom, or at least one side of the first conical spouted bed reactor stage, and / or the first and second conical spouted bed reactor stages are at different relative heights.

6. 10. The system of claim 1, wherein the first conical spouted bed reactor stage is configured to receive catalyst from the catalyst regenerator, and / or the second conical spouted bed reactor stage is in fluid communication with the catalyst regenerator and configured to receive catalyst from the catalyst regenerator, and / or the first conical spouted bed reactor stage operates in a pyrolysis regime.

7. 7. The system of claim 6, wherein the flow of catalyst from the catalyst regenerator to the first conical spouted bed reactor stage is adjustable in response to the temperature in the first conical spouted bed reactor stage falling below a predetermined temperature setpoint, and / or the flow of catalyst from the catalyst regenerator to the second conical spouted bed reactor stage is adjustable in response to the temperature in the second conical spouted bed reactor stage falling below a predetermined temperature setpoint.

8. 10. The system of claim 1, further comprising a draft tube extending from a bottom of the first conical spouted bed reactor stage toward a top of the first conical spouted bed reactor stage, the draft tube comprising a cylindrical tube having an outer diameter smaller than an inner diameter of the bottom of the first conical spouted bed reactor stage and at least one opening extending upward from the bottom of the draft tube.

9. 10. The system of claim 1, further comprising a confiner extending from a top of the first conical spouted bed reactor stage toward a bottom of the first conical spouted bed reactor stage, the confiner comprising a cylindrical tube having an outer diameter smaller than an inner diameter of the top of the first conical spouted bed reactor stage.

10. 10. The system of claim 1, further comprising a third conical spouted bed reactor stage in fluid communication with said second conical spouted bed reactor stage.

11. 10. The system of claim 1, wherein the first conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C during operation, and / or the second conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C during operation.

12. 10. The system of claim 1, further comprising a gas supply system in fluid communication with the first conical spouted bed reactor stage and the second conical spouted bed reactor stage, the gas supply system configured to supply a motive gas to the first conical spouted bed reactor stage and the second conical spouted bed reactor stage.

13. 13. The system of claim 12, wherein the drive gas contains less than 1.0 wt. % oxygen, or more preferably less than 0.1 wt. % oxygen.

14. 10. The system of claim 1, further comprising a set of separation cyclones in fluid communication with the first conical spouted bed reactor stage and the second conical spouted bed reactor stage.

15. 1. A method for producing hydrocarbon products from plastics, comprising: feeding the plastic feedstock and a drive gas to a first conical spouted bed reactor stage containing a catalyst to produce a first product vapor and a first residual plastic; separating at least a portion of the first product vapor from the drive gas and the first residual plastics to produce a first product stream comprising the first product vapor; feeding the first residual plastic from the first conical spouted bed reactor stage to a second conical spouted bed reactor stage containing a catalyst to produce a second product vapor and a second residual plastic; separating at least a portion of the second product vapor from the drive gas and the second residual plastic to produce a second product stream comprising the second product vapor; A method comprising:

16. 16. The method of claim 15, further comprising transferring at least a portion of the catalyst from a first conical spouted bed reactor stage to the second conical spouted bed reactor stage and / or further comprising transferring at least a portion of the catalyst from a second conical spouted bed reactor stage to a regenerator.

17. 16. The method of claim 15, further comprising feeding catalyst from the regenerator to the first conical spouted bed reactor stage and / or further comprising feeding catalyst from the regenerator to the second conical spouted bed reactor stage.

18. 17. The method of claim 16, wherein the transfer of the portion of the catalyst from the first conical spouted bed reactor stage to the second conical spouted bed reactor stage is driven, at least in part, by a flow of a drive gas, and / or the transfer of the portion of the catalyst from the second conical spouted bed reactor stage to the regenerator is driven, at least in part, by a flow of a drive gas.

19. 16. The method of claim 15, wherein the first conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C, and / or the second conical spouted bed reactor stage has a temperature of from about 300°C to about 650°C, or from about 450°C to about 600°C, or from about 480°C to about 550°C.

20. 20. The method of claim 19, wherein the temperature of the first conical spouted bed reactor stage is controlled in part by supplying hot catalyst from the regenerator to the first conical spouted bed reactor stage, and / or the temperature of the second conical spouted bed reactor stage is controlled in part by supplying hot catalyst from the regenerator to the second conical spouted bed reactor stage.

21. 16. The method of claim 15, wherein the plastic feedstock is first shredded to a nominal size of about 1 mm to about 20 mm or about 8 mm to about 10 mm before being fed into the first conical spouted bed reactor stage.

22. 16. The method of claim 15, wherein the first conical spouted bed reactor stage and the second conical spouted bed reactor stage are both contained within a single reactor vessel.

23. 16. The method of claim 15, further comprising: feeding the second residual plastic from the second conical spouted bed reactor stage to a third conical spouted bed reactor stage containing a catalyst to produce a third product vapor and a residue; and separating the third product vapor, drive gas, and residue to produce a third product stream comprising the third product vapor.

24. 16. The method of claim 15, further comprising directing the first product stream and the second product stream into a cyclone separator.

25. 25. The method of claim 24, wherein the first product stream and the second product stream are combined before being directed into a set of cyclone separators.

26. 16. The method of claim 15, further comprising collecting the first product stream and the second product stream in a separation vessel.

27. 16. The method of claim 15, wherein the plastic raw material comprises high density polyethylene, medium density polyethylene, low density polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, or a mixture of any two or more thereof.

28. the first hydrocarbon product and the second hydrocarbon product are C １ ~C １２ Saturated hydrocarbons, C １ ~C １２ 16. The method of claim 15, wherein the first hydrocarbon product and the second hydrocarbon product comprise an olefin, an aromatic compound, or a mixture of any two or more thereof, and the first hydrocarbon product and the second hydrocarbon product can be the same or different, and / or the first hydrocarbon product and the second hydrocarbon product comprise an olefin, an aromatic compound, or a mixture of any two or more thereof.

29. 16. The method of claim 15, further comprising processing and purifying one or more of the first hydrocarbon product, the second hydrocarbon product, the first plastic residue, or the second plastic residue in a steam cracker, a hydrocracker, a fluid catalytic cracker, a deep catalytic cracker, a high severity fluid catalytic cracker, a steam reformer, a liquid cracked gas plant, or an aromatics recovery unit.

30. 16. The method of claim 15, wherein the size of the first conical spouted bed reactor stage is the same as the size of the second conical spouted bed reactor stage, and / or the method is carried out continuously, and / or the plastic feedstock comprises waste plastic.

31. 16. The method of claim 15, wherein separating the at least a portion of the first product vapor from the drive gas and the first residual plastic to produce a first product stream comprising the first product vapor occurs in the first conical spouted bed reactor stage.

32. 16. The method of claim 15, wherein the first product stream is removed from the first conical spouted bed reactor stage immediately upon formation, and / or the second product stream is removed from the second conical spouted bed reactor stage immediately upon formation.

33. 16. The method of claim 15, wherein separating the at least a portion of the second product vapor from the drive gas and the second residual plastic to produce a second product stream comprising the second product vapor occurs in the second conical spouted bed reactor stage.

34. 16. The method of claim 15, wherein the average gas phase residence time in the first conical spouted bed reactor stage is from about 0.2 seconds to about 60 seconds, or preferably from about 0.5 seconds to about 5 seconds, and / or the average gas phase residence time in the second conical spouted bed reactor stage is from about 0.2 seconds to about 60 seconds, or preferably from about 0.5 seconds to about 5 seconds.

35. 16. The method of claim 15, wherein the drive gas contains less than 1.0 wt. % oxygen, or more preferably less than 0.1 wt. % oxygen, and / or the first conical spouted bed reactor stage and the second conical spouted bed reactor stage operate in a fast pyrolysis regime.

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