Trace metal-containing coking process and coke composition

Abstract

A method of sequestering contaminant compounds from polymer waste can include thermally cracking at least a feedstock comprising polymer waste and a coker feedstock to produce at least coke and a coking effluent comprising hydrocarbons, where the polymer waste comprises chlorine and / or chloride compounds, wherein at least a portion of the chlorine and / or chloride compound is segregated into coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compound; and separating at least a portion of the coker effluent to form coker naphtha.

Description

Cross Reference to Related Applications

[0001] This application claims the benefit of and priority to U.S. Provisional Application No. 63 / 492,775, filed March 28, 2023, the disclosure of which is incorporated herein by reference. TECHNICAL FIELD

[0002] Systems and methods of contaminant management in chemical recycling of plastic waste are provided. BACKGROUND

[0003] Chemical recycling processes, such as pyrolysis, are used to break down plastic waste to form recycled hydrocarbons. Plastic waste often contains additives such as fillers, colorants, UV inhibitors, talc, CaC03, metals such as Al and Mg, metal salts such as TiCl4, CaCl2, NaCl, and metal oxides such as Ti02and Si02, and metal fatty acid salts such as calcium stearate, magnesium stearate, and zinc stearate. The recycled hydrocarbons are often contaminated with one or more additives that can adversely affect downstream processes, for example, via catalyst deactivation, corrosion, and build-up within the unit. Chloride-containing compounds are often generated from chemical recycling of polymer waste, which can be particularly difficult to handle in recycled hydrocarbons. While specialized processing systems can be used to handle recycled hydrocarbons generated from polymer waste recycling, such specialized systems require significant initial capital costs and a constant supply of waste feedstock. SUMMARY SUMMARY

[0004] Disclosed herein are example methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises chlorine and / or chloride compounds, wherein at least a portion of the chlorine and / or chloride compounds are segregated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compounds; and separating at least a portion of the coking effluent to form a coker naphtha.

[0005] Further disclosed herein are methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is segregated into the coke, and wherein the coke comprises 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coker naphtha. SUMMARY SUMMARY

[0004] Disclosed herein are example methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises chlorine and / or chloride compounds, wherein at least a portion of the chlorine and / or chloride compounds are segregated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compounds; and separating at least a portion of the coking effluent to form a coker naphtha.

[0005] Further disclosed herein are methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is segregated into the coke, and wherein the coke comprises 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coker naphtha. SUMMARY SUMMARY

[0004] Disclosed herein are example methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises chlorine and / or chloride compounds, wherein at least a portion of the chlorine and / or chloride compounds are segregated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compounds; and separating at least a portion of the coking effluent to form a coker naphtha.

[0005] Further disclosed herein are methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is segregated into the coke, and wherein the coke comprises 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coker naphtha. SUMMARY SUMMARY

[0004] Disclosed herein are example methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises chlorine and / or chloride compounds, wherein at least a portion of the chlorine and / or chloride compounds are segregated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compounds; and separating at least a portion of the coking effluent to form a coker naphtha.

[0005] Further disclosed herein are methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is segregated into the coke, and wherein the coke comprises 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coker naphtha. SUMMARY SUMMARY

[0004] Disclosed herein are example methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises chlorine and / or chloride compounds, wherein at least a portion of the chlorine and / or chloride compounds are segregated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compounds; and separating at least a portion of the coking effluent to form a coker naphtha.

[0005] Further disclosed herein are methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is segregated into the coke, and wherein the coke comprises 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coker naphtha. SUMMARY SUMMARY

[0004] Disclosed herein are example methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises chlorine and / or chloride compounds, wherein at least a portion of the chlorine and / or chloride compounds are segregated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compounds; and separating at least a portion of the coking effluent to form a coker naphtha.

[0005] Further disclosed herein are methods of sequestering contaminant compounds from polymer waste, which can include: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is segregated into the coke, and wherein the coke comprises 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coker naphtha. SUMMARY SUMMARY

[0004]

[0006] Further disclosed herein are example petroleum coke compositions comprising: at least 95 wt% carbon; chlorine and / or chloride compounds in an amount of about 0.01 wt% to about 1 wt%; titanium in an amount of about 0.01 wt% to about 1 wt%; aluminum in an amount of about 0.01 wt% to about 1 wt%; and vanadium in an amount of about 0.01 wt% to about 1 wt%.

[0007] These and other features and attributes of the disclosed methods and systems of the present disclosure will become apparent with reference to the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0008] To assist a person of ordinary skill in the relevant art in making and using the subject matter of the present application, reference is made to the accompanying drawings, in which:

[0009] Figure 1 is an exemplary plot of a process for pyrolyzing polymer waste followed by coking.

[0010] Figure 2 is an exemplary plot of a fluidized bed coking system including a coker, a heater, and a gasifier according to certain embodiments of the present disclosure.

[0011] Figure 3 is an exemplary plot of a fluidized bed coking system including a coker and a gasifier according to certain embodiments of the present disclosure.

[0012] Figure 4 is an exemplary plot of a delayed coking system including a coker and a fractionator according to certain embodiments of the present disclosure.

[0013] Figure 5 is an X-ray image of a cross-section of a coke sphere produced by vacuum resid coking of polymer waste according to certain embodiments of the present disclosure.

[0014] Figure 6 is extracted spectral data from X-ray dispersive spectroscopy of a coke sphere according to certain embodiments of the present disclosure.

[0015] Figure 7 is a plot of a thermogravimetric analysis curve of iron (III) chloride hydrolysis according to certain embodiments of the present disclosure.

[0016] Figure 8 is a plot of a Fourier transform infrared spectrum of iron (III) chloride hydrolysis according to certain embodiments of the present disclosure. DETAILED DESCRIPTION

[0017] In various embodiments, systems and methods for chemical recycling of polymer waste, such as plastic waste, are provided. One challenge of chemical recycling of polymer waste is that the resulting recycled product often contains contaminants that are incompatible with downstream processes. When contaminants are present in the recycled product, they can be difficult to handle, thereby reducing the value of the recycled product. In some embodiments, the polymer waste contains chlorides and / or chloride-containing compounds, which can contaminate units and poison catalysts.

[0018] In some embodiments, polymer waste is chemically recycled by co-processing the polymer waste with co-feeds in a coker to produce a coking product. The coking product can include hydrocarbon gases and liquid products, such as coking naphtha and petroleum coke. In addition, the coking process at least partially separates and concentrates contaminants that can be present in the polymer waste, thereby reducing the contaminants in the coker hydrocarbon product. Some example contaminants can include, but are not limited to, chlorides and / or chloride-containing compounds and metals, such as titanium, aluminum, silicon, calcium, magnesium, and zinc. In embodiments, the concentration of contaminants, such as chlorides and / or chloride-containing compounds, in the coker hydrocarbon product can be monitored, and the feed to the coker can be adjusted to reduce the concentration of contaminants in the coker hydrocarbon product.

[0019] The coker hydrocarbon product can be used to produce circular chemical products. Circular chemical products are chemical products derived from polymer waste, where the molecules of the chemical product can be attributed to the polymers in the polymer waste, such as by accounting for, allocating, offsetting, and / or displacing other hydrocarbons in the mass balance or energy balance of the system. Circular chemical products include circular monomers, circular aromatics, and circular polymers, among others. Polymers that have their circularity certified by a third party can be referred to as certified circulars. One example of such certification is the mass balance chain of custody method set forth by the International Sustainability and Carbon Certification. Coker feed

[0020] According to embodiments of the application, coking can be used to process waste feedstocks to produce a coking product. In some embodiments, the waste feedstock is co-processed with conventional coking feedstocks.

[0021] Waste feedstocks for coking can include or consist essentially of one or more types of polymers, such as polymers corresponding to plastic waste containing chlorine and / or chlorine-containing compounds. The systems and methods described herein can be suitable for processing polymer waste corresponding to a single type of polymer and / or polymer waste corresponding to multiple polymers. In aspects where the waste feedstock consists essentially of polymers, the feedstock can include one or more types of polymers as well as any additives, modifiers, packaging dyes, and / or other components that are typically added to polymers during and / or after formulation. The waste feedstock can further include components typically found in polymer waste (e.g., paper).

[0022] In some embodiments, the waste feedstock includes polymer waste obtained from any source, including but not limited to municipal, industrial, commercial, or consumer sources. In some embodiments, the waste feedstock includes post-consumer use plastics. The polymer waste can also include plastics obtained from a common source or from mixed sources, including mixed plastic waste obtained from municipal or regional sources and / or from waste streams of PET, HDPE, LDPE, LLDPE, polypropylene, and / or polystyrene. Further, the waste feedstock can include thermoplastic elastomers and thermoset rubbers, such as from tires and other articles made from natural rubber, polybutadiene, styrene-butadiene, butyl rubber, and EPDM.

[0023] Further still, examples of suitable waste feedstocks can include any of a variety of used polymer articles, without limitation. Some examples of many types of polymer articles can include: films (including cast, blown, and others), sheets, fibers, woven and nonwoven fabrics, furniture (e.g., garden furniture), sporting equipment, bottles, food and / or liquid storage containers, transparent and translucent articles, toys, pipes and tubing, sheeting, packaging, bags, packs, coatings, caps, closures, crates, pallets, cups, non-food containers, tubs, insulation, and / or medical devices. Other examples include industrial waste streams, such as linear alpha-olefins and polypropylene heavy streams (e.g., > 50 wt%). Other examples include automotive, aerospace, boat, and / or marine components (e.g., bumpers, grilles, trim parts, instrument panels, instrument boards, etc.), wire and cable sheathing, agricultural films, geomembranes, sports field equipment, and other such articles, whether blow molded, rotational molded, injection molded, etc. Any of the foregoing articles can include mixtures of polymeric and non-polymeric articles (e.g., packaging or other articles can include inks, paperboard, paper, metal deposition layers, etc.). One of ordinary skill will appreciate that such polymer articles can be made from any of a variety of polymeric and / or non-polymeric materials, and that the polymeric materials can vary widely (e.g., ethylene-based, propylene-based, butyl-based polymers, and / or polymers based on any C2 to C10 alpha-olefin, etc.).40 or even higher order olefins, and also include polymers based on any one or more types of monomers, such as C2 to C 40 monomers such as ethylidene norbornene (ENB) and vinyl norbornene (VNB) (including, for example, when such cyclic olefins are used as comonomers, such as with ethylene monomers).

[0024] In various embodiments, the waste feedstock can include one or more nitrogen-containing polymers. Examples of nitrogen-containing polymers include polyamides (e.g., nylon 6), polyurethanes, and polynitriles. The nitrogen-containing polymers can correspond to 0.1 wt% to 25 wt% (relative to the weight of the waste feedstock), or 1.0 wt% to 25 wt%, or 5.0 wt% to 25 wt%, or 10 wt% to 25 wt%, or 1.0 wt% to 15 wt%, or 5.0 wt% to 15 wt%, or 1.0 wt% to 10 wt% of the waste feedstock. For example, the nitrogen-containing polymers can be present in the waste feedstock in an amount of 25 wt% or less, 10 wt% or less, 5 wt% or less, 1 wt% or less, or 0.1 wt% or less.

[0025] In some embodiments, the waste feedstock can include one or more chlorine-containing polymers. Examples of chlorine-containing polymers include PVC (polyvinyl chloride) and PVDC (polyvinylidene chloride). In some aspects, the chlorine-containing polymers can correspond to 0.001 wt% to 15 wt% (relative to the weight of the waste feedstock), or 0.1 wt% to 15 wt%, or 1.0 wt% to 15 wt%, or 0.001 wt% to 10 wt%, or 0.1 wt% to 10 wt%, or 1.0 wt% to 10 wt%, or 0.001 wt% to 5.0 wt%, or 0.001 wt% to 1.0 wt% of the waste feedstock. For example, the chlorine-containing polymers can be present in the waste feedstock in an amount of 15 wt% or less, 10 wt% or less, 5 wt% or less, 1 wt% or less, or 0.1 wt% or less.

[0026] In some embodiments, the waste feedstock can include at least one of polyethylene and polypropylene. The polyethylene can correspond to any suitable type of polyethylene, such as high density or low density versions of polyethylene. Likewise, any suitable type of polypropylene can be used. In addition, or alternatively, the waste feedstock can include one or more of polystyrene, polyamide (e.g., nylon), polyethylene terephthalate, and ethylene vinyl acetate. Other polyolefins can correspond to polymers (including copolymers) of butadiene, isoprene, and isobutylene. In some embodiments, the polyethylene and polypropylene can be present in the mixture as a copolymer of ethylene and propylene. More generally, the polyolefins can include copolymers of various olefins, such as ethylene, propylene, butylene, hexene, and / or any other olefin suitable for polymerization.

[0027] In this discussion, the weight of the polymer in the feedstock corresponds to the weight relative to the total polymer content in the feedstock, unless otherwise indicated. Any additives and / or modifiers and / or other components included in the formulated polymer are included in this weight. However, the weight percentages described herein do not include any solvent or carrier that can optionally be used to facilitate the delivery of the polymer to the coker.

[0028] In some embodiments, the waste feedstock includes 0.01 wt% to 35 wt%, or 0.1 wt% to 35 wt%, or 1 wt% to 35 wt%, or 0.01 wt% to 20 wt%, or 0.1 wt% to 20 wt%, or 1 wt% to 20 wt%, or 10 wt% to 35 wt%, or 5 wt% to 20 wt%, or 0.01 wt% to 10 wt%, or 0.01 wt% to 1 wt% of polystyrene. In some embodiments, the waste feedstock can also include oxygen-containing polymers, such as polyterephthalates. It should be noted that polyamides also contain oxygen as part of the polymer structure. In this discussion, polymers that include oxygen and nitrogen as part of the repeating units used to form the polymer are defined as nitrogen-containing polymers for the purpose of characterizing the waste feedstock.

[0029] In addition to the polymers, the waste feedstock can also include various other components. Such other components can include additives, modifiers, packaging dyes, and / or other components that are typically added to the polymer during and / or after formulation. The waste feedstock can further include any components that are typically found in polymer waste. Finally, the feedstock can also include a carrier fluid, such that the waste feedstock for the cracking process corresponds to a solution or slurry of the polymer waste.

[0030] As discussed above, polymer waste often contains impurities used in the polymer production process to impart desired properties to the polymer. Such impurities can include, but are not limited to, nitrogen-containing compounds, sulfur-containing compounds, and heavy metals, such as aluminum, boron, calcium, chromium, cobalt, iron, manganese, magnesium, molybdenum, nickel, potassium, phosphorus, silicon, sodium, titanium, vanadium, and combinations thereof. Polymer waste can contain metal salts and oxides, such as Ti02, talc, CaC03, Si02, TiCl4, CaCl2, and NaCl. In embodiments, the polymer waste can contain any of the above impurities in an amount of 0.001 wt% to 15 wt%, based on the weight of the polymer waste. Alternatively, the impurities can be present in an amount of 0.001 wt% to 0.005 wt%, 0.005 wt% to 0.01 wt%, 0.01 wt% to 0.05 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1.0 wt%, 1.0 wt% to 5.0 wt%, 5.0 wt% to 10.0 wt%, 10.0 wt% to 15.0 wt%, or any range therein.

[0031] In some aspects, the chlorine-containing polymer can correspond to 0.001 wt% to 15 wt% (relative to the weight of the waste feedstock), or 0.1 wt% to 15 wt%, or 1.0 wt% to 15 wt%, or 0.001 wt% to 10 wt%, or 0.1 wt% to 10 wt%, or 1.0 wt% to 10 wt%, or 0.001 wt% to 5.0 wt%, or 0.001 wt% to 1.0 wt% of the waste feedstock. For example, the chlorine-containing polymer can be present in the waste feedstock in an amount of 15 wt% or less, 10 wt% or less, 5 wt% or less, 1 wt% or less, or 0.1 wt% or less.

[0032] In embodiments where the waste feedstock is introduced into the coking environment at least partially as a solid, having a small particle size can facilitate transport of the solid and / or reduce the likelihood of incomplete conversion. In some embodiments, the waste feedstock includes polymeric waste having a median particle size of 0.01 mm to 50 mm, 0.01 to 25 mm, 0.01 to 10 mm, 1 mm to 50 mm, 1 mm to 25 mm, 1 mm to 10 mm, 5 mm, or 0.1 mm to 5 mm, or 0.01 mm to 3 mm, or 0.1 mm to 3 mm, or 0.01 mm to 3 mm, or 0.1 mm to 3 mm, or 1 mm to 5 mm, or 1 mm to 3 mm. To determine the median particle size, the particle size is defined as the diameter of the smallest bounding sphere containing the particle. Additionally or alternatively, the polymeric waste in the waste feedstock can be melted and / or pelletized to improve the uniformity of the particle size of the plastic particles. In some embodiments, the polymeric waste has a maximum particle size of 10 mm or less, or 5 mm or less. Additionally or alternatively, the polymeric waste can be provided in a waste bale. In some embodiments, the waste bale is a composite bale.

[0033] It should be noted that some types of polymeric waste can also include biologically derived components. For example, some types of plastic labels can include biogenic waste in the form of a paper compound. In some embodiments, 1 wt% to 25 wt% of the waste feedstock can correspond to biologically derived materials. Such biologically derived materials can also contribute to the nitrogen and / or oxygen content of the waste feedstock.

[0034] Optionally, a carrier fluid can also be included in the waste feedstock to aid in the introduction of the polymeric waste into the cracking environment. To introduce into the cracking environment, the feedstock can conveniently be in the form of a slurry. If a carrier fluid is used to transport the waste feedstock, any suitable fluid can be used. Examples of suitable carrier fluids can include, but are not limited to, a wide range of petroleum or petrochemical products. For example, some suitable carrier fluids include crude oil, naphtha, kerosene, diesel, light or heavy cycle oils, cat cracker slurry, and gas oil. Other potential carrier fluids can correspond to naphthenic and / or aromatic solvents, such as toluene, benzene, methylnaphthalene, cyclohexane, methylcyclohexane, and mineral spirits. Other carrier fluids can correspond to refinery fractions, such as a gas oil fraction or a naphtha fraction from a coker. In another example, distillate and / or gas oil boiling range fractions produced by cracking the waste feedstock alone or with additional feedstock can be used.

[0035] In various embodiments, coking is used to co-process a combined feedstock corresponding to a mixture of conventional coking feedstock and waste feedstock. In some embodiments, the conventional coking feedstock is used as a carrier fluid for the waste feedstock. The conventional coking feedstock can correspond to one or more types of petroleum and / or renewable feedstock having a suitable boiling range for cracking (e.g., processing in a coker). The amount of waste feedstock in the combined feedstock can correspond to 1 wt% to 50 wt%, 3 wt% to 50 wt%, 10 wt% to 50 wt%, 25 wt% to 50 wt%, 1 wt% to 25 wt%, 1 wt% to 10 wt%, 1 wt% to 5 wt%, 1 wt% to 3 wt%, 3 wt% to 25 wt%, 10 wt% to 25 wt%, 3 wt% to 15 wt%, or any range therebetween, of the combined feedstock. The conventional coking feedstock can correspond to 50 wt% to 99 wt% of the combined feedstock entering the coker.

[0036] In some embodiments, the coking feedstock used for co-processing with the waste feedstock can correspond to a conventional petroleum feedstock having a relatively high boiling point fraction, such as a heavy oil feed. For example, the coking feedstock portion of the feed can have a T10 distillation point of 343°C or higher, or 371°C or higher. In some embodiments, the coking feedstock has a T10 distillation point of 343°C to 650°C. Examples of suitable heavy oils included in the coking feedstock include reduced petroleum crude; petroleum atmospheric distillation column bottoms; petroleum vacuum distillation column bottoms or residue; asphalt; bitumen; asphaltenes; other heavy hydrocarbon residues; tar sand oil; shale oil; or even coal slurry or coal liquefaction products, such as coal liquefaction column bottoms. Such feeds typically have a Conradson Carbon Residue (ASTM D189-165) of at least 5 wt%, often 5 wt% to 50 wt%. In some embodiments, the coking feedstock includes petroleum vacuum residue.

[0037] Some examples of conventional petroleum feedstocks suitable for processing in a delayed coker or fluidized bed coker can have compositions and properties within the ranges listed in Table 1 below. Table 1

[0038] In addition to petroleum feedstocks, renewable feedstocks derived from biomass having a suitable boiling range can also be used as part of the cracking feed. Such renewable feedstocks include feedstocks having a T10 boiling point of 340°C or higher and a T90 boiling point of 600°C or lower. Examples of suitable renewable feedstocks derived from biomass can be cracking oil feedstocks that are at least partially derived from biomass.

[0039] In some particular embodiments, the waste feedstock and the conventional coking feedstock (e.g., coker feedstock) are mixed to form a combined feedstock prior to introduction into the coking environment. In other embodiments, the waste feedstock and the conventional coking feedstock are introduced separately into the coking environment. However, more typically, any suitable method for introducing both the waste feedstock and the coking feedstock into the coking environment can be used.

[0040] Prior to introduction into the coking environment, the feedstock (optionally in the form of a combined feedstock) is preheated according to one or more embodiments. Preheating the feedstock in one or more heating stages can increase the temperature of the feedstock to a mixing and storage temperature, to a temperature associated with a cracking temperature, or to another suitable temperature.

[0041] In some embodiments, a portion of the preheating of the waste feedstock can be performed by mixing the waste feedstock with the coking feedstock in a mixing tank and heating the mixture in the mixing tank. For example, the waste feedstock and the coking feedstock can be mixed in a heated agitated tank for storage operating at 200 °C to 325 °C or 275 °C to 325 °C. In some embodiments, tank agitation aids in the uniform dispersion of the waste feedstock into the residual oil and maintains the slurry suspension. Heating in the mixing tank provides heat to the combined feedstock prior to introduction of the combined feedstock into the cracking reaction environment. This can reduce or minimize the additional cracking heat load that would otherwise be required to heat the waste feedstock to the thermal cracking temperature. The mixed feedstock can be further heated and / or physically processed to reduce particle size prior to injection into the cracking reactor. The size of the combined feedstock can be set to provide particles having a maximum particle size of, for example, 5 mm or less, 2 mm or less, or 1 mm or less. In some embodiments, the particles are sized with a grinding device, such as a roll mill. In addition to heating, a stripping gas can be used to strip the combined waste feedstock and coking feedstock in the mixing tank. Passing a stripping gas through the combined feedstock can aid in the removal of gases entrained in the combined feedstock.

[0042] In some embodiments, the waste feedstock is melted, for example in an extruder. After extrusion, the waste feedstock comprising the melted polymer waste can be mixed directly with the conventional coking feedstock and / or solvent, or the extruded plastic can be pelletized to form the desired particle size of the waste feedstock.

[0043] According to certain embodiments, yet another option can be to mix the waste feedstock with the coking feedstock after the preheater furnace of the coker. In these embodiments, the coking feedstock can be heated to a higher temperature in the preheater, and then the waste feedstock can be added to the preheated coking feedstock to heat the waste feedstock. Pyrolysis

[0044] According to one or more embodiments, waste feedstock is pyrolyzed to produce pyrolysis oil, which is then fed to a coking environment. In some embodiments, the waste feedstock is pyrolyzed with one or more additional feedstocks, such as a rubber-containing feedstock. In some embodiments, the pyrolysis oil derived at least in part from a polymer waste is co-processed in a coking environment with a conventional coking feedstock.

[0045] Pyrolysis is a chemical recycling technology that includes the thermal degradation of a pyrolysis feedstock to produce gaseous and liquid products known as pyrolysis oil and pyrolysis gas. A waste plastic pyrolysis unit is different from a coker unit, which is specifically designed to handle heavier feeds. Pyrolysis products can depend on many factors, including but not limited to, pyrolysis reactor temperature, pyrolysis reactor pressure, reactor residence time, feed type, feed quality, and process configuration.

[0046] A specific pyrolysis technique will now be described in more detail. In an example embodiment, a pyrolysis feedstock (e.g., a waste feedstock) can be provided, for example, in the form of granules, flakes, or pellets, and fed to a pyrolysis unit. In the pyrolysis unit, the waste feedstock can be melted to produce a molten liquid (e.g., molten plastic). For example, a polymer waste can be melted in an extruder to a temperature of 300°C to 320°C. The molten liquid can be heated to a higher temperature, for example, 390°C to 550°C, while being agitated, in a pyrolysis chamber. Long chain hydrocarbons (e.g., about 30 carbon atoms or longer) in the produced pyrolysis gas can then be condensed and further pyrolyzed for further thermal degradation, while shorter chain hydrocarbons can exit in gaseous form. For example, the produced pyrolysis gas can be directed to a contactor to contact a row of condenser elements (e.g., plates), upon which the long chain hydrocarbons can condense. The long chain hydrocarbons can flow back from the condenser to the pyrolysis chamber. The pyrolysis gas comprising the shorter chain hydrocarbons can be distilled in a distillation column to provide a pyrolysis gas and a pyrolysis oil.

[0047] Figure 1 An example configuration for pyrolyzing a waste feedstock and then coking is shown. In Figure 1 In the example configuration, a waste feedstock 100 and one or more optional feedstocks 102 are fed to a pyrolysis unit 104. The waste feedstock 100 comprises a polymer waste, such as a plastic waste, wherein the polymer waste comprises chlorine- and / or chloride-containing compounds. In the pyrolysis unit 104, the waste feedstock 100 containing the polymer waste can be pyrolyzed to form at least a pyrolysis gas 106 and a pyrolysis oil 108. The pyrolysis unit 104 can include various different equipment suitable for polymer waste pyrolysis, including but not limited to, reactors, extruders, tanks, vessels, valves, sensors, hoppers, conveyance systems, and piping, among others.

[0048] Pyrolysis oil 108, at least partially derived from polymer waste, is then fed to a coking stage 112. Coking stage 112 corresponds to any suitable coking for coking pyrolysis oil, including a delayed coker, a fluid coker, or a combination thereof. As shown, conventional coking feedstock 110 can also be fed to coking stage 112, in accordance with one or more embodiments. In coking stage 112, the combined feedstock of pyrolysis oil 108 and conventional coking feedstock 110 is processed to form at least a coking effluent. In Figure 1 In the example shown, the coking effluent can be separated to form a coker gas fraction 114, a coker naphtha fraction 116, and a coker gas oil fraction 118. A coke product 120 is also shown, but it should be understood that coke product 120 is typically removed from the coker separately from the coker effluent. Coking

[0049] In accordance with one or more embodiments, waste feedstock is coked, alone or with conventional coking feedstock, to produce more valuable coking products (coking effluent). In various aspects, co-processing can be performed by exposing a combined feedstock of waste feedstock and conventional coking feedstock to coking conditions.

[0050] Coking is a refining process that includes the thermal cracking of longer chain molecules into shorter chain molecules, with excess carbon left over as coke. Coking processes in modern refinery environments can generally be classified as delayed coking or fluidized bed coking. In both processes, feedstock is cracked to produce gas and liquid products, leaving coke behind. In delayed coking, feedstock is heated and fed to a coking reactor (often referred to as a "coke drum"), where cracking occurs. To remove coke, an alternate drum can be used. In fluidized coking, feedstock is fed to a coking reactor, where cracking occurs, with coke transferred from the coking reactor to a heater as a fluidized solid.

[0051] Coking products produced from coking include a cracking effluent, which can include gas, liquid, or a mixture thereof. The cracking effluent can be fractionated or otherwise separated to form desired product streams, such as coker gas (e.g., C4and lighter hydrocarbons), coker naphtha, and coker gas oil.

[0052] Coking gas is a coker effluent fraction formed in a coker having a T90 distillation point of 40°C or less. Coking gas is a mixture of many different hydrocarbons, including paraffins, olefins, and aromatics. Coking gas can include hydrocarbons of 1 carbon atom to 5 carbon atoms. Coking gas can additionally include trace amounts of higher hydrocarbons (e.g., C6), including benzene in the gas. Although coking gas is referred to as a gas, it should be understood that coking gas can be in liquid form, for example, depending on the temperature and pressure, so long as the coking gas has a final boiling point of 100°C or less.

[0053] Coking gas oil is a coker effluent fraction formed in a coker having a T10 distillation point of 225°C or more and a T90 distillation point of 650°C or less. Coking gas oil is a mixture of many different hydrocarbons, including paraffins, olefins, and aromatics. Coking gas oil can include hydrocarbons of 8 carbon atoms to 70 carbon atoms.

[0054] Coking naphtha is a liquid coker effluent fraction formed in a coker having a T10 distillation point of 30°C or more and a T90 distillation point of 220°C or less. Coking naphtha is a mixture of many different hydrocarbons, including paraffins, naphthenes, olefins, and aromatics. Coking naphtha can include hydrocarbons of 4 carbon atoms to 12 carbon atoms.

[0055] Hydrocarbon coking products derived at least in part from polymer waste, including coking gas, coking gas oil, and coking naphtha, can have certain desirable reductions in components compared to hydrocarbon coking products derived from conventional hydrocarbon feedstocks, such as reductions in aromatic content and sulfur content and reductions in impurities associated with processing polymer waste. For example, hydrocarbon coking products derived from conventional hydrocarbon feedstocks can have an aromatic content of about 1 wt% to 25 wt%, while hydrocarbon coking products derived at least in part from polymer waste can have an aromatic content of 10 wt% to 20 wt%, or 10 wt% to 15 wt%, or 15 wt% to 20 wt%. Hydrocarbon coking products also show a reduction in 2-3 ring aromatics. For example, hydrocarbon coking products derived at least in part from polymer waste can have a 2-3 ring aromatic content of 0 wt% to 5 wt% or 1 wt% to 3 wt%. As another example, hydrocarbon coking products derived from conventional hydrocarbon feedstocks can have a sulfur content of 0.5 wt% to 5 wt%, while hydrocarbon coking products derived at least in part from polymer waste can have a lower sulfur content, such as 0.1 wt% or less.

[0056] In addition to the desired reduction in aromatics and sulfur, the hydrocarbon coking product derived at least in part from polymer waste can have increased levels of other components that can complicate subsequent chemical processing. These components include, for example, organic halides and basic nitrogen. The specific types and amounts of these components depend on, for example, the particular polymer waste used to form the coking product. For example, the hydrocarbon coking product derived at least in part from polymer waste can have a total halide content, such as chlorine, fluorine, and bromine, in an amount of, for example, 1 wppm to 0.5 wt%, 10 wppm to 0.5 wt%, or 10 wppm to 0.1 wt%, while a hydrocarbon coking product derived from a conventional hydrocarbon feedstock can include organic contaminants at levels below 1 wppm. As another example, the hydrocarbon coking product derived at least in part from polymer waste can include basic nitrogen at levels of 100 wppm to 5,000 wppm, while a hydrocarbon coking product from a conventional hydrocarbon feedstock can include basic nitrogen at levels of 10 wppm to 50 wppm.

[0057] The basic nitrogen content of a feed, fraction, or product as used herein can be determined according to the following method by measuring two samples of the feed, fraction, or product. First, the total nitrogen of the sample is characterized according to ASTM D4629. Next, the sample can be acid-washed by adding 1 ml of 1 N sulfuric acid to a 10 ml sample. This mixture can be formed in a suitable container, such as a 20 ml pipette. The mixture of sample and sulfuric acid is shaken vigorously and then allowed to settle for 5 minutes. After settling, the sulfuric acid should be at the bottom of the container. The acid-washed sample is removed from the top of the container, for example, by using a pipette to remove the acid-washed sample without including any of the sulfuric acid. The acid-washed sample can then be characterized according to ASTM D4629. The difference in nitrogen content between the untreated sample and the acid-washed sample corresponds to the nitrogen removed by the acid treatment. In this discussion, the nitrogen removed by the acid treatment is defined as the basic nitrogen content. Amides and amines present in the sample correspond to basic nitrogen, so the presence of excess amides and amines in the sample due to the decomposition of nitrogen-containing polymers will result in a corresponding increase in the basic nitrogen content of the sample.

[0058] The coking product further includes coke. Because many polymer wastes have a relatively low sulfur content (compared to conventional coking feedstocks), in some embodiments, the cracking product has a reduced sulfur content, thus reducing the severity required for any subsequent desulfurization processes (e.g., hydroprocessing). Coke produced in the coking process is generally a carbonaceous solid material that is mostly carbon. In embodiments, the coke can contain 90 wt% carbon to 99.99 wt% carbon. Alternatively, 90 wt% carbon to 95 wt% carbon, 95 wt% to 99 wt%, 99 wt% to 99.99 wt%, or any range therein. Alternatively, the coke can contain at least 90 wt% carbon, at least 95 wt% carbon, at least 99 wt% carbon, or at least 99.99 wt% carbon.

[0059] According to one or more embodiments, because the coke is produced from the co-processing of conventional coking feedstocks in a coker, it can also be referred to as petroleum coke or petcoke. The coke yield is typically 20 to 40 wt% of the combined coker feedstock. However, because polymer waste can have a significantly higher atomic ratio of hydrogen to carbon, coking with polymer waste feedstock can produce a reduced or minimized amount of coke. The specific composition of the coke depends on many factors, including the specific coking process, such as a delayed coker or a fluidized coker.

[0060] In embodiments, the coke can contain contaminants from the polymer waste. The coking process separates contaminants from the polymer waste into the coke, thereby reducing the concentration of contaminants in other coking products. In some embodiments, the coke can include aluminum in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0061] In some embodiments, the coke can include boron in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0062] In some embodiments, the coke can include calcium in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0063] In some embodiments, the coke can include chromium in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0064] In some embodiments, the coke can include cobalt in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0065] In some embodiments, the coke can include iron in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0066] In some embodiments, the coke can include manganese in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0067] In some embodiments, the coke can include magnesium in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0068] In some embodiments, the coke can include molybdenum in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0069] In some embodiments, the coke can include nickel in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0070] In some embodiments, the coke can include potassium in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0071] In some embodiments, the coke can include phosphorus in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0072] In some embodiments, the coke can include silicon in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0073] In some embodiments, the coke can include sodium in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0074] In some embodiments, the coke can include titanium in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0075] In some embodiments, the coke can include vanadium in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0076] In some embodiments, the coke can include Ti02in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0077] In some embodiments, the coke can include talc (Mg3Si4O 10 (OH)2) in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0078] In some embodiments, the coke can include CaC03in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0079] In some embodiments, the coke can include Si02in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0080] In some embodiments, the coke can include TiC14in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0081] In some embodiments, the coke can include CaCl2in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0082] In some embodiments, the coke can include NaCl in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0083] In some embodiments, the coke can include calcium stearate in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0084] In some embodiments, the coke can include magnesium stearate in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0085] In some embodiments, the coke can include zinc stearate in an amount of 0.01 wt% to 2 wt%. Alternatively, 0.01 wt% to 0.05 wt%, 0.05 wt% to 0.1 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 1 wt%, 1.0 wt% to 1.5 wt%, 1.5 wt% to 2 wt%, or any range therebetween.

[0086] The coked polymer waste containing contaminants referred to herein can have several advantages over other polymer recycling technologies, such as catalytic recycling, where contaminants can accumulate and catalyst deactivation can occur. Catalytic recycling can require additional unit operations to purge accumulated contaminants. It can be advantageous to use polymer waste as a co-feed in a coking operation because there is no catalyst deactivation and the contaminant compounds are at least partially separated into the coke. Thus, the contaminants, such as chlorine and / or chloride containing compounds, are removed from the process so that the materials do not passivate the catalyst or cause corrosion in downstream units. The contaminants from the polymer waste that are separated into the coke can be a minor component of the coke and do not affect the value or properties of the coke. In embodiments, the coke can contain contaminants, including chlorine and / or chloride containing compounds, from the polymer waste in an amount of 0.01 wt% to 1 wt%. Alternatively, in an amount of 0.01 wt% to 2 wt%. Alternatively, in an amount of 0.01 wt% to 0.05 wt%, in an amount of 0.05 wt% to 0.1 wt%, in an amount of 0.1 wt% to 0.5 wt%, in an amount of 0.5 wt% to 1 wt%, in an amount of 1.0 wt% to 1.5 wt%, in an amount of 1.5 wt% to 2 wt%, or any range therein.

[0087] In embodiments, the coke can include a combination of contaminants. For example, the coke composition can include at least 80 wt% carbon, with the remainder being chemical species other than carbon, where at least a portion of the chemical species is from polymer waste. Alternatively, at least 85 wt% carbon, with the remainder being chemical species other than carbon, where at least a portion of the chemical species is from polymer waste. Alternatively, at least 90 wt% carbon, with the remainder being chemical species other than carbon, where at least a portion of the chemical species is from polymer waste. Alternatively, at least 95 wt% carbon, with the remainder being chemical species other than carbon, where at least a portion of the chemical species is from polymer waste. Alternatively, at least 99 wt% carbon, with the remainder being chemical species other than carbon, where at least a portion of the chemical species is from polymer waste. Table 2 shows typical contaminant amounts in coke produced by the methods described herein. Table 2 Coking conditions - fluidized coking

[0088] According to one or more embodiments, the polymer waste can be processed in a fluidized coker. In some embodiments, the plastic waste is co-processed with conventional coking feedstocks. In various aspects, co-processing can be performed by exposing a combined feedstock of waste feedstock and conventional coking feedstock to fluidized coking conditions.

[0089] Fluid coking is a petroleum refining process in which a heavy petroleum feed, usually the non-distillable residue from the fractionation of heavy oil (residuum), is converted into lighter, more useful products by thermal decomposition (coking) at elevated reaction temperatures, typically 480°C to 590°C, and in most cases 500°C to 550°C. Examples of heavy oils suitable for processing by the fluid coking process include heavy atmospheric residuum, petroleum vacuum distillation column bottoms, aromatic extracts, asphalt, and bitumen from tar sands, tar pits, and pitch lakes. In accordance with embodiments of the present application, plastic waste is processed in the fluid coking vessel alone or in combination with conventional coker feedstocks.

[0090] Fluid coking is carried out in a unit having a large reactor containing hot coke particles maintained under fluidized conditions at the desired reaction temperature, with steam injected at the bottom of the vessel, where the average direction of movement of the coke particles is downward through the bed. In particular embodiments, the combined feedstock can be heated to a pumpable temperature, typically in the range of 350°C to 400°C, mixed with atomizing steam, and fed through a plurality of feed nozzles arranged at several successive levels in the reactor. Steam is injected into a stripping section at the bottom of the reactor and passes upward through the coke particles, which descend through the dense phase of the fluidized bed in the main body portion of the reactor above the stripping section. A portion of the feed liquid coats the coke particles in the fluidized bed, which subsequently crack to form a solid coke layer and lighter products that evolve as gas or vaporized liquid. The residence time of the feed in the coking zone, where the temperature is suitable for thermal cracking, is about 1 to 30 seconds. The reactor pressure is relatively low in order to promote vaporization of hydrocarbon vapors that pass upward from the dense phase of the fluidized bed in the coking zone into the dilute phase and into cyclone separators at the top of the coking zone, where the bulk of the entrained solids are separated from the gas phase by centrifugal force in one or more cyclone separators and returned to the dense fluidized bed by gravity through cyclone diplegs. The mixture of steam and hydrocarbon vapors from the reactor is then discharged from the cyclone gas outlets into a scrubber section in a plenum chamber located above the coking zone and separated therefrom by a partition. It is quenched in the scrubber section by contact with liquid descending above the slots. A pumparound loop circulates the condensed liquid to an external cooler and back to the top slot row of the scrubber section to provide cooling of the quenched material and condensation of the heaviest fraction of the liquid product. This heavy fraction is typically recycled to extinction by feeding back into the coking zone in the reactor.

[0091] In a fluid coking process, coking feedstock (pre-heated to a temperature at which it is flowable and pumpable) is introduced into a coking reactor through injection nozzles directed toward the top of the reactor vessel, the injection nozzles configured to produce a spray of feed into the fluidized bed of coke particles in the vessel. The temperature in the coking zone of the reactor is typically in the range of 450°C to 650°C, and the pressure is maintained at a relatively low level, typically in the range of 0 kPag to 700 kPag, most typically 35 kPag to 320 kPag, in order to promote rapid drying of the coke particles, preventing the formation of sticky, adherent high molecular weight hydrocarbon deposits on the particles that can lead to fouling of the reactor. In some embodiments, the temperature in the coking zone can be 450°C to 600°C, or 450°C to 550°C. Conditions can be selected so that a desired amount of feedstock conversion occurs in the fluidized bed reactor. For example, conditions can be selected to achieve at least 10 wt% conversion relative to 343°C (or 371°C), or at least 20 wt% conversion relative to 343°C (or 371°C), or at least 40 wt% conversion relative to 343°C (or 371°C), for example up to 80 wt% conversion or possibly higher. The light hydrocarbon products of the coking (thermal cracking) reaction vaporize, mix with the fluidizing steam and pass upward through the dense phase of the fluidized bed into the dilute phase zone above the dense fluidized bed of coke particles. This mixture of vaporized hydrocarbon products formed in the coking reaction flows upward with the steam through the dilute phase at a superficial velocity of about 1 to 2 meters / second (~ 3 to 6 feet / second), entraining some of the fine solid particles of coke, which are separated from the cracked vapors in a reactor cyclone separator as described above. In embodiments in which steam is used as the fluidizing agent, the weight of steam introduced into the reactor can be selected relative to the weight of feedstock introduced into the reactor. For example, the mass flow rate of steam into the reactor can correspond to 6.0%, or 8.0% or higher, for example up to 10% or possibly higher, of the mass flow rate of feedstock. If an activated light hydrocarbon stream is used as part of the stripping and / or fluidizing gas in the reactor, the amount of steam can potentially be reduced. In such embodiments, the mass flow rate of steam can correspond to 6.0% or less, or 5.0% or less, or 4.0% or less, or 3.0% or less, of the mass flow rate of feedstock. Optionally, in some embodiments, the mass flow rate of steam can also be lower, for example corresponding to 1.0% or less, or 0.8% or less, or 0.6% or less, of the mass flow rate of feedstock, for example as low as substantially all of the steam being replaced by an activated light hydrocarbon stream. The cracked hydrocarbon vapors exit the cyclone separator into a scrubbing section of the reactor, and then to product fractionation and recovery.

[0092] In a typical fluid coking process, coke particles formed in the coking zone pass downwardly through the reactor and exit the bottom of the reactor vessel through a stripping section where they are exposed to steam to remove occluded hydrocarbons. The solid coke (consisting primarily of carbon with lesser amounts of hydrogen, sulfur, nitrogen, and trace amounts of vanadium, nickel, iron, and other elements derived from the feed) from the reactor passes through a stripper and out of the reactor vessel to a burner or heater where it is partially combusted in a fluidized bed with air to raise its temperature from 480°C to 700°C to supply the heat required for the endothermic coking reactions, after which a portion of the hot coke particles are recycled to the fluidized bed reaction zone to transfer heat to the reactor and act as nuclei for coke formation. The balance is withdrawn as a coke product. The net coke yield is only 65% of that produced by delayed coking.

[0093] For a coking process that includes a gasification zone, the coking process is conducted in a reactor with coke particles passing downwardly through a coking zone, through a stripping zone where occluded hydrocarbons are stripped by an upflowing stream of fluidizing gas (steam). They then exit the coking reactor and enter a gasification reactor (gasifier) that contains a fluidized bed of solid particles and is operated at a higher temperature than the coking zone of the reactor. In the gasifier, the coke particles are converted to a fuel gas comprising carbon monoxide and hydrogen by reacting with steam and an oxygen-containing gas at an elevated temperature.

[0094] The gasification zone is typically maintained at an elevated temperature of 850°C to 1,000°C and a pressure of 0 kPag to 1000 kPag, preferably 200 kPag to 400 kPag. Steam and an oxygen-containing gas are introduced to provide fluidization and an oxygen source for gasification. In some embodiments, the oxygen-containing gas can be air. In other embodiments, the oxygen-containing gas can have a low nitrogen content, such as oxygen gas from an air separation unit or another oxygen gas stream comprising 95 vol% or more, or 98 vol% or more oxygen gas that is passed into the gasifier to react with the solid particles comprising coke deposited thereon in the coking zone. In embodiments where the oxygen-containing gas has a low nitrogen content, a separate diluent stream, such as a recycle CO2or H2S stream derived from the fuel gas produced by the gasifier, can also be passed into the gasifier.

[0095] In the gasification zone, reactions between the coke and steam and oxygen-containing gas produce fuel gas containing hydrogen and carbon monoxide, and partially gasified residual coke product. Conditions in the gasifier are correspondingly selected to produce these products. The steam and oxygen rates (and any optional CO2 rate) will depend on the rate of cold coke entering the reactor, and to a lesser extent on the composition of the coke, which in turn will vary depending on the composition of the heavy oil feed and the severity of the cracking conditions in the reactor, which are selected in accordance with the feed and the range of liquid products desired. In some embodiments, the fuel gas product from the gasifier contains entrained coke solids, and these are removed by a cyclone separator or other separation technique in the gasifier portion of the cyclone unit. Suitable cyclones include internal cyclones in the main gasifier vessel itself or external cyclones in a separate smaller vessel as described below. The fuel gas product is withdrawn from the gasifier cyclone as an overhead. The resulting partially gasified solids are withdrawn from the gasifier and introduced directly into the coking zone of the coking reactor at a dilute phase level above the denser phase.

[0096] In some embodiments, the coking conditions can be selected to provide a desired amount of conversion relative to 343°C. Generally, the desired amount of conversion can correspond to 10 wt% or more, or 50 wt% or more, or 80 wt% or more relative to 343°C, for example up to substantially complete conversion of the feedstock.

[0097] The volatile products from the coke drum are carried away from the process for further processing. For example, the volatiles can be directed to a coker fractionator for distillation and recovery of coker gas, coker naphtha, light gas oil, and heavy gas oil. These fractions are typically, but not always, used after upgrading in blends of fuel and lubricating oil products such as automotive gasoline, automotive diesel, fuel oil, and lubricating oil. Upgrading can include separation, removal of heteroatoms via hydrotreating and non-hydrotreating processes, dearomatization, solvent extraction, and the like. The process is compatible with processes in which at least a portion of the heavy coker gas oil present in the product stream introduced into the coker fractionator is captured for recycle and combined with fresh feed (coker feed component) to form a coker heater or coking furnace charge. The combined feed ratio ("CFR") is the volumetric ratio of the furnace charge (fresh feed plus recycle oil) to fresh feed for a continuous flow coker operation. Flow coking operations typically employ 5 to 35 vol% recycle (CFR of 1.05 to 1.35). In some embodiments, there can be no recycle, and sometimes in special applications, the recycle can be as high as 200%.

[0098] Flexicoking process developed by Exxon Research and Engineering Company TMThe process is a type of fluid coking process that operates in units including a reactor and a heater, but also includes a gasifier for gasifying the coke product by reaction with an air / steam mixture to form a low heating value fuel gas. The coke stream flows from the heater to the gasifier where all but a small portion of the coke stream is gasified to a low BTU gas (~120 BTU / standard cubic foot) by the addition of steam and air in a fluidized bed in an oxygen deficient environment to form a fuel gas comprising carbon monoxide and hydrogen. In a conventional Flexicoking TM In the configuration, the fuel gas product from the gasifier containing entrained coke particles is sent back to the heater to provide the majority of the heat required for thermal cracking in the reactor while balancing the reactor heat demand provided by combustion in the heater. A small amount of net coke (about 1% of the feed) is taken from the heater to purge metals and ash from the system. Liquid yields and properties are comparable to those from fluid coking. The fuel gas product is taken from the heater after separation in an internal cyclone which sends the coke particles back through its dipleg.

[0099] In this specification, the term "Flexicoking" (a trademark of ExxonMobil) is used to mean a fluid coking process in which a heavy petroleum feed is subjected to thermal cracking in a fluidized bed of heated solid particles to produce hydrocarbons of lower molecular weight and boiling point and as a byproduct, coke which is deposited on the solid particles in the fluidized bed. Reference to a fluid coker is intended to include both conventional fluid cokers as well as flexicokers. The resulting coke can then be converted to a fuel gas by contact with steam and an oxygen-containing gas at elevated temperature in a gasification reactor (gasifier). This type of configuration can be referred to more generally as an integration of fluid bed coking with gasification. Figure 3 and Figure 4 Examples of fluid coking reactors including a gasifier are provided.

[0100] Figure 2 An example of a Flexicoker unit (i.e., a system including a gasifier thermally integrated with a fluid bed coker) is shown having three reaction vessels: a reactor, a heater, and a gasifier. The coking system 200 includes a coker reactor 202 having a coking zone and its associated stripping and washing sections (not shown separately), a heater 204, and a gasifier 206. A coking feedstock, which can be a waste feedstock (or a combined feedstock of a waste feedstock and a conventional coking feedstock), is introduced into the coking system 200 through line 208 and the coker effluent is discharged through line 210. While the coking system 200 is shown as a single unit, it is understood that the coking system 200 can be a plurality of units, e.g., a plurality of coker reactors, a plurality of heaters, and a plurality of gasifiers. Figure 2Combined feedstocks are shown, but example embodiments also include separately introducing conventional coking feedstocks and waste feedstocks into the coker reactor 202. Fluidization and stripping steam is supplied through line 212. Cold coke is withdrawn from the stripping section of the bottom of the coker reactor 202 through line 214 and sent to the heater 204. Of course, the term "cold" when applied to the temperature of the withdrawn coke is obviously relative, as it is much higher than ambient temperature at the operating temperature of the stripping section. Hot coke is cycled from the heater 204 to the coker reactor 202 through line 216. Coke from the heater 204 is transferred to the gasifier 206 through line 218, and hot partially gasified coke particles are cycled from the gasifier back to the heater 204 through line 220. Excess coke is withdrawn from the heater 204 via line 222. In a conventional configuration, the gasifier 206 is supplied with steam and air through line 224, and hot fuel gas is taken from the gasifier to the heater through line 226. In some alternative embodiments, instead of supplying air to the gasifier 206 via line 224, a stream of oxygen at a purity of 95 vol% or greater, such as from an air separation unit, can be provided. In such embodiments, in addition to supplying the stream of oxygen, an additional diluent gas stream can be supplied through line 228. The additional diluent gas can correspond to, for example, CO2 separated from the fuel gas produced during gasification. Fuel gas is withdrawn from the unit through line 230 over the heater; coke fines are removed from the fuel gas in a heater cyclone system 232, which includes primary and secondary cyclones with diplegs that return separated fines to the fluidized bed in the heater, connected in series. The fuel gas from line 230 can then be further processed. For example, in some embodiments, the fuel gas from line 230 can be sent to a separation stage to separate CO2 (and / or H2S). This can produce a stream with increased concentration of syngas, which can then be sent to a conversion stage to convert the syngas to methanol.

[0101] It should be noted that in some optional embodiments, the heater cyclone system 232 can be located in a separate vessel (not shown) rather than in the heater 204. In such aspects, the line 230 can take the fuel gas from the separate vessel and the line 222 for sweeping excess coke can correspond to a line that transports the coke fines away from the separate vessel. These coke fines and / or other partially gasified coke particles that are discharged from the heater (or gasifier) can have an increased metal content relative to the feedstock. For example, the weight percent of metal in the coke particles that are discharged from the system (relative to the weight of the discharged particles) can be greater than the weight percent of metal in the feedstock (relative to the weight of the feedstock). In other words, the metal from the feedstock is concentrated in the discharged coke particles. Because the gasifier conditions do not produce a slag, the discharged coke particles correspond to a mechanism for removing metal from the coker / gasifier environment. In some embodiments, the metal can correspond to a combination of nickel, vanadium, and / or iron. Additionally or alternatively, the gasifier conditions can not substantially result in the deposition of metal oxides on the interior walls of the gasifier, for example, less than 0.1 wt.%, or less than 0.01 wt.% of the metal present in the feedstock introduced into the coker / gasifier system is deposited.

[0102] In configurations such as Figure 2 The system elements shown in the figures can be characterized based on the fluid communication between the elements. For example, the coker reactor 202 is in direct fluid communication with the heater 204. The coker reactor 202 is also in indirect fluid communication with the gasifier 206 via the heater 204.

[0103] As an alternative, integration of the fluidized bed coker and gasifier can also be achieved without the use of an intermediate heater. In such alternative aspects, the cold coke from the reactor can be directly transferred to the gasifier. In almost all cases, this transfer will be explicitly direct, with one end of a tubular transfer line connected to the coke outlet of the reactor and the other end connected to the coke inlet of the gasifier, without an intermediate reaction vessel, i.e., a heater. However, the presence of equipment other than the heater, such as an inlet for lift gas, etc., is not excluded. Similarly, while the hot, partially gasified coke particles from the gasifier are returned directly from the gasifier to the reactor, this simply means that there is no intermediate heater as in a conventional three-vessel Flexicoker TM but there can be other equipment between the gasifier and the reactor, such as a gas lift inlet and outlet.

[0104] Figure 3 An example is shown in which the fluidized bed coker is integrated with the gasifier but there is no separate heater vessel. In Figure 3In the illustrated configuration, the cyclone separator for separating fuel gas from catalyst fines is located in a separate vessel. In other aspects, the cyclone separator can be included in the main gasifier vessel 304.

[0105] In Figure 3 In the illustrated configuration, the coker system 300 includes a coker reactor 302, a main gasifier vessel 304, and a separator vessel 306. Coking feedstock is introduced into the coker reactor 302 via line 308, and fluidization / stripping gas is introduced via line 310; coker effluent is withdrawn via line 312. The coking feedstock includes waste feedstock, optionally combined with conventional coking feedstock, such as heavy oil feed. For example, the waste feedstock can be introduced into the coker reactor 302 alone or in combination with conventional coking feedstock. The cold, stripped char is transported directly from the coker reactor 302 to the main gasifier vessel 304 via line 314, and the hot char is returned to the reactor in line 316. Steam and oxygen are supplied via line 318. A gas stream containing char fines is transported to the separator vessel 306 via line 320, which is connected to a gas outlet of the main gasifier vessel 304. The fines are separated from the gas stream in a cyclone separator system 322, which includes primary and secondary cyclone separators connected in series with diplegs that return the separated fines to the separator vessel. The separated fines are then returned to the main gasifier vessel 304 via return line 324, and a fuel gas product is withdrawn via line 326. Char is purged from the separator via line 328. The fuel gas from line 326 can then be further processed to separate CO2(and / or H2S) and convert the syngas to methanol.

[0106] The coker and gasifier can be operated according to the parameters required for the desired coking process. Thus, the heavy oil feed in the coking feedstock will typically be a heavy (high boiling point) reduced crude oil; petroleum atmospheric distillation column bottoms; petroleum vacuum distillation column bottoms or residue; asphalt; pitch; asphaltenes; other heavy hydrocarbon residue; tar sand oil; shale oil; or even coal slurry or coal liquefaction products, such as coal liquefaction column bottoms. Such feeds typically have a Conradson Carbon Residue (ASTM D189-165) of at least 5 wt%, often 5 wt% to 50 wt%. In some embodiments, the coking feedstock is petroleum vacuum residue. Coking conditions - delayed coking

[0107] In particular embodiments, the waste feedstock, optionally combined with conventional coking feedstock, is subjected to delayed coking to produce liquid and vapor hydrocarbon products and coke. In various embodiments, the waste feedstock and optional conventional coking feedstock are exposed to delayed coking conditions.

[0108] Delayed coking is another coking process used to thermally convert heavy oil such as petroleum residuum (also known as "resid") to produce liquid and vapor hydrocarbon products and coke. In some embodiments, the conventional hydrocarbon feedstock includes resid from heavy and / or sour (high sulfur) crude oil. Delayed coking of the feedstock is performed by converting a portion of the feedstock to more valuable hydrocarbon products. The resulting coke has value as a fuel (fuel grade coke), electrodes for aluminum manufacture (anode grade coke), etc. depending on its grade.

[0109] Typically, the feedstock is pumped to a preheater where it is preheated to a temperature of, for example, 480°C to 520°C. The preheated feed is directed through an inlet at the bottom of a drum to a coking reactor, typically an insulated coker vessel oriented vertically, such as a drum. The pressure in the drum is typically low, for example, 100 kPa-g to 550 kPa-g, or 100 kPa-g to 240 kPa-g, to allow removal of volatiles at the top. The typical operating temperature of the drum will be between about 400°C to 445°C, but can be as high as 475°C. The hot feed thermally cracks in the coke drum over a period of time ("coking time") releasing volatiles consisting primarily of hydrocarbon products that continuously rise through the coke bed, which is composed of channels, pores, and pathways, and are collected at the top. The volatile products are directed to a coker fractionator for distillation and recovery of coker gas, gasoline boiling range materials such as coker naphtha, light gas oil, and heavy gas oil. In one embodiment, a portion of the heavy coker gas oil present in the product stream introduced into the coker fractionator can be captured for recycle and combined with fresh feed (coker feed component) to form a coker heater or coker furnace charge. In addition to the volatile products, this process results in the accumulation of coke in the drum. When the coke drum is full of coke, the heated feed is switched to another drum and the coke tower is purged of hydrocarbon vapors with steam. The drum is then quenched with water to reduce the temperature to 95°C to 150°C, after which the water is drained. When the draining step is complete, the drum is opened and the coke is removed by drilling and / or cutting using high velocity water jets ("hydraulic decoking").

[0110] Figure 4An example delayed coking system 400 is shown. In the illustrated embodiment, a feedstock 402 comprising a waste feedstock, which can be preheated, is fed into a coker fractionator 404. In some embodiments, the feedstock 402 also includes a conventional coking feedstock, which can also be fed separately into the coker fractionator 404. In the illustrated embodiment, a fractionator effluent 406 comprising at least a portion of the waste feedstock and / or the conventional coking feedstock is withdrawn from the coker fractionator 404 and fed into a coker furnace 408. A preheated effluent 410 comprising the preheated waste feedstock and / or the preheated conventional coking feedstock is transferred from the coker furnace 408 to a coking reactor 412, which includes, for example, a coking vessel or coking drum. The preheated effluent 410 also includes, for example, a bottoms product (or recycle). The coking reactor 412 is operated under coking conditions such that the preheated waste feedstock / conventional coking feedstock thermally cracks in the coking reactor 412 over a period of time (“coking time”), releasing volatiles consisting primarily of hydrocarbon products that continuously rise through a coke bed composed of channels, pores, and pathways, and are collected at the top as a coker effluent 414, which is transferred to the coker fractionator 404. In the illustrated embodiment, the coker effluent 414 is separated into various fractions in the coker fractionator 404, including, but not limited to, one or more of a coking gas fraction 418, a coking naphtha fraction 420, and a coking gas oil fraction 422. It will be appreciated that separation of the coking products into various fractions can occur in one or more vessels and / or one or more different operations. As mentioned earlier, coke accumulates in the coker reactor 412 (e.g., coking vessel). A coke product 416 comprising the coke is withdrawn from the coker reactor 412. Chemical production

[0111] According to one or more embodiments, processing of the polymer waste results in production or recovery of chemical products. For example, one or more fractions of a hydrocarbon coking product from coking of polymer waste can be processed to form a chemical product. Example hydrocarbon coking products include coking gas, coking naphtha, and / or coking gas oil. As another example, one or more fractions of a coker effluent from coking of pyrolysis oil, which is at least partially derived from polymer waste, can be processed to form a chemical product.

[0112] In some embodiments, the fraction of the hydrocarbon coking product includes one or more components that need to be removed and / or reduced in concentration prior to subsequent processing. For example, embodiments include treating the fraction of the hydrocarbon coking product to remove at least a portion of contaminants, including halides, acids, and sulfur species. Any of a variety of techniques can be used to treat the fraction of the hydrocarbon coking product, including absorption, adsorption, hydroprocessing, filtration, and fractionation. Adsorption can be used to remove specific contaminants, such as mercury. Examples of specific adsorption techniques include treatment beds, such as mercury beds. Absorption includes solid and liquid contact methods, such as water wash, amine gas treatment, caustic treatment. Water wash includes, for example, contacting the fraction of the hydrocarbon coking product with a stream of water. Example hydroprocessing techniques include hydrogenation and hydroprocessing. Embodiments of hydroprocessing can also convert organic halides in the hydrocarbon coking product fraction to inorganic acids. A neutralizing additive can then be added to the hydroprocessing effluent to neutralize the resulting inorganic acids. In some embodiments, mercury is removed, for example, by mercaptan oxidation. Solids particles are removed, for example, using filtration.

[0113] Chemical products produced by the integration of co-processing of polymer waste include a variety of chemical products, including olefins (e.g., alpha-olefins), aromatics, oligomers, and polymers. A "polymer" has one or more repeating units that are the same or different. As used herein, the term "polymer" includes oligomers (up to 75 repeating units) and larger polymers (more than 75 repeating units). A "homopolymer" is a polymer having the same repeating unit. A "copolymer" is a polymer having two or more repeating units that are different from each other. A "terpolymer" is a polymer having three repeating units that are different from each other. "Different" is used to mean that the repeating units differ from each other by at least one atom or are isomerically different from each other. Thus, as used herein, the definition of copolymer includes terpolymer and the like. The chemical products include or can be processed to form a number of desirable products, including: olefins, such as ethylene, propylene, butene, butadiene, pentene, C5 olefins, and C5 dienes, and longer olefins, such as hexene, nonene, and tetramer; aromatics, such as benzene, styrene, and toluene; cyclohexane; polymers, such as polyethylene, polypropylene, polystyrene, polyesters, polyvinyl chloride; and dichloroethylene; synthetic elastomers and rubbers, such as styrene-butadiene rubber, ethylene-propylene-diene rubber, butyl rubber, and halogenated butyl rubber; plastic additives and modifiers, such as plasticizers; epoxy resins; and fluids with a variety of applications, such as isopropyl alcohol, carbonyl alcohol, glycol, detergent, and lubricant.

[0114] At least a portion of these chemical products can be a circular chemical product attributable to polymer waste, for example, as determined by crediting, allocating, and / or offsetting or replacing other hydrocarbons in the mass or energy balance of the system, for example, according to third-party certification related to circularity. At least a portion of these chemical products can be an certified circular chemical product, which is certified by a third-party certification of its circularity can be referred to as a certified circular.

[0115] Various methods can be employed to integrate chemical production with coking. For example, a portion of the hydrocarbon coking product received from coking can be converted in one or more of the following units: hydroprocessing units, such as hydrocracking and hydrotreating units; fluid catalytic cracking units; steam cracking units; catalytic reforming units; partial oxidation to syngas; and / or isomerization. Chemical products can be produced directly by such methods, or can be obtained by further processing, such as separation, treatment, and / or cracking, of the effluent of such methods. As an example, chemical products can be obtained by processing a portion of the hydrocarbon coking product at least partially derived from polymer waste. Additionally, co-processing polymer waste as a feed or co-feed into a delayed or fluidized coking unit, including a FLEXICOKING TM unit, can result in polymer waste being attributable to chemical products, including olefins, polymers, or aromatics, for example, as determined by crediting, allocating, and / or offsetting or replacing other hydrocarbons in the mass or energy balance of the system, for example, according to third-party certification related to circularity.

[0116] Accordingly, methods according to various embodiments herein can further include obtaining olefins that have been produced or recycled from the processing of polymer waste or that the processing of polymer waste is attributable to, for example, for use in a polymerization process; and polymers of various embodiments described herein can include olefins that have been produced or recycled from the processing of polymer waste or that the processing of polymer waste is attributable to. As an example, at least a portion of the olefin content (e.g., used in a method as described herein and / or included in a composition as described herein) can be from olefins produced or recycled directly from the processing of polymer waste. Similarly, the processing of polymer waste can be attributable to at least a portion of the olefins (e.g., olefins used in a method as described herein and / or included in a composition as described herein). Additional embodiments

[0117] Accordingly, the present disclosure can provide integration of polymer waste co-processing in a coker for the production of circular chemical products from coker naphtha. The methods and systems can include any of the various features disclosed herein, including one or more of the following embodiments.

[0118] Embodiment 1. A method of sequestering a contaminant compound from a polymer waste, comprising: at least pyrolyzing a feedstock comprising a polymer waste and a coker feedstock to produce at least coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises a chlorine and / or chloride compound, wherein at least a portion of the chlorine and / or chloride compound is isolated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compound; and separating at least a portion of the coking effluent to form a coking naphtha.

[0119] Embodiment 2. The method of embodiment 1, wherein the coking naphtha has a concentration of chlorine and / or chloride compound in an amount of about 1 wppm to about 0.5 wt%, a 2-3 ring aromatic compound content of about 0 wt% to about 5 wt%, and a sulfur content of about 750 ppm to about 2 wt%.

[0120] Embodiment 3. The method of any one of embodiments 1-2, wherein the polymer waste further comprises at least one contaminant selected from the group consisting of nitrogen, sulfur, aluminum, boron, calcium, chromium, cobalt, iron, manganese, magnesium, molybdenum, nickel, potassium, phosphorus, silicon, sodium, titanium, vanadium, and combinations thereof.

[0121] Embodiment 4. The method of embodiment 3, wherein the coke further comprises each of the at least one contaminant in an amount of about 0.01 wt% to about 1 wt%.

[0122] Embodiment 5. The method of any one of embodiments 1-4, wherein the coker feedstock comprises a heavy oil having a T10 distillation point of about 343°C to about 575°C.

[0123] Embodiment 6. The method of embodiment 5, wherein the heavy oil comprises petroleum vacuum residue.

[0124] Embodiment 7. The method of any one of embodiments 1-6, wherein the feedstock comprises the polymer waste in an amount of about 0.1 wt% to about 25 wt%.

[0125] Embodiment 8. The method of any one of embodiments 1-7, further comprising converting the coking naphtha into at least a polymer.

[0126] Embodiment 9. The method of embodiment 8, wherein at least a portion of the polymer is attributable to one or more polymers in the polymer waste.

[0127] Embodiment 10. The method of any one of embodiments 8-9, wherein the polymer comprises a recycled polymer.

[0128] Embodiment 11. The method of any one of embodiments 8-10, wherein at least a portion of the polymer is an authenticated recycled material according to International Sustainability and Carbon Certification.

[0129] Embodiment 12. The method of any one of embodiments 8-11, wherein the coker naphtha is further converted into at least one chemical product selected from the group consisting of monomers, aromatic compounds, synthetic elastomers, synthetic rubbers, epoxy resins, resins, isopropyl alcohol, oxo alcohols, and combinations thereof.

[0130] Embodiment 13. The method of any one of embodiments 8-12, wherein converting the coker naphtha into at least a polymer comprises cracking at least a portion of the coker naphtha to form at least a cracked effluent, recovering olefins from the cracked effluent; and polymerizing at least a portion of the olefins to form at least a polyolefin.

[0131] Embodiment 14. The method of any one of embodiments 1-13, wherein the coking effluent further comprises a coking gas and wherein the coking gas comprises chlorine and / or chloride compounds in an amount of from about 0 wt% to about 0.001 wt%.

[0132] Embodiment 15. The method of any one of embodiments 1-14, wherein the coking effluent further comprises a coking gas oil and wherein the coking gas oil comprises chlorine and / or chloride compounds in an amount of from about 0 wt% to about 0.001 wt%.

[0133] Embodiment 16. A method of sequestering contaminant compounds from polymer waste, comprising: at least thermally cracking a feedstock comprising polymer waste and a coker feedstock to produce at least coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is isolated into the coke, and wherein the coke comprises from 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coker naphtha.

[0134] Embodiment 17. The method of embodiment 16, wherein the metal further comprises at least one additional metal selected from the group consisting of aluminum, calcium, magnesium, zinc, and combinations thereof.

[0135] Embodiment 18. The method of any one of embodiments 16-17, wherein the coke further comprises the additional metal in an amount of from about 0.01 wt% to about 1 wt%.

[0136] Embodiment 19. A petroleum coke composition, comprising: at least 95 wt% carbon; chlorine and / or chloride compounds in an amount of from about 0.01 wt% to about 1 wt%; titanium in an amount of from about 0.01 wt% to about 1 wt%; aluminum in an amount of from about 0.01 wt% to about 1 wt%; and vanadium in an amount of from about 0.01 wt% to about 1 wt%.

[0137] Embodiment 20. The petroleum coke composition of Embodiment 19, wherein at least a portion of the carbon is attributable to one or more polymers from a polymer waste from thermal cracking.

[0138] Embodiment 21. The petroleum coke composition of Embodiment 20, wherein the polymer waste comprises plastic waste.

[0139] Embodiment 22. The petroleum coke composition of Embodiment 19, further comprising at least one contaminant selected from the group consisting of nitrogen, sulfur, boron, calcium, chromium, cobalt, iron, manganese, magnesium, molybdenum, nickel, potassium, phosphorus, silicon, sodium, and combinations thereof, in an amount of about 0.01 wt% to about 1 wt%.

[0140] In order to facilitate a better understanding of the application, the following examples of certain aspects of some embodiments are given. The following examples should in no way be interpreted as limiting, or as limiting the full scope of the present disclosure. Example 1

[0141] In this example, a plastic feedstock containing chloride compounds and petroleum vacuum residue were co-processed in a refinery coking unit. Coke spheres were collected from the coking unit and analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Prior to analysis by SEM and EDS, the coke sample was embedded in cold-mounting epoxy resin, mechanically cross-sectioned and polished.

[0142] Figure 5 is an X-ray image of a cross-section of a coke sphere. Figure 6 is spectral data extracted from EDS of a coke sphere. A local concentration of chlorine of 0.1 wt% was observed in the analyzed portion of the coke sphere, indicating the segregation of chloride compounds from the plastic feedstock into the coke sphere. It was further observed that the analyzed portion of the coke sphere contained titanium and aluminum local concentrations in an amount of 0.1 wt%. Example 2

[0143] In this example, the hydrolysis of sodium chloride (NaCl) and calcium chloride (CaCl2) was compared to the hydrolysis of magnesium chloride (MgCl2) and iron (III) chloride (FeCl3) in a simulated coking environment. Inorganic chlorides can pose a risk of corrosion under coker conditions, as inorganic chlorides can hydrolyze to hydrochloric acid (HC1). In this example, humidified argon gas was used as a source of moisture. Two reactor temperatures were chosen, 432 °C and 551 °C to simulate coker conditions. The inorganic chlorides tested were placed in humidified argon gas heated at 10 °C / min until the desired reactor temperature was reached, and then held for 1 hour. The hydrolysis reaction of the inorganic chlorides was monitored by thermogravimetric analysis (TGA) coupled with Fourier-transform infrared spectroscopy (FTIR). Figure 7is a plot of the thermogravimetric analysis curve of hydrolysis of iron (III) chloride, Figure 8 is a plot of the Fourier transform infrared spectrum of hydrolysis of iron (III) chloride.

[0144] Table 3 shows the results of the hydrolysis experiments. It was observed that magnesium chloride and iron (III) chloride were completely hydrolyzed at both of the selected temperatures. It was further observed that sodium chloride and calcium chloride were partially hydrolyzed at both temperatures, but the higher temperature resulted in a greater degree of hydrolysis.

[0145] The results of these experiments were extrapolated to estimate the hydrolysis at thermal dechlorination temperatures. It is noted that these estimates are higher than the actual expectation because the experiments were done with a single component (just the salt) and do not embody the effects of mass transfer. In reality, some of these inorganic chlorides can be in the polymer matrix and, in the case of co-processing in a coker, the inorganic chlorides will be in the bulk of the coker hydrocarbon and parameters such as mixing, viscosity, residence time, moisture content, etc. will affect the % hydrolysis. Table 3 Inorganic chlorides 432°C coking 551°C coking 343°C, thermal de-Cl NaCl 10％ 25％ 10％ MgCl2 100％ 100％ 25％ CaCl2 10％ 25％ 10％ FeCl3 100％ 100％ 80％

[0146] While the present disclosure has been described in some embodiments and examples, one skilled in the art will understand that other embodiments can be devised without departing from the scope and spirit of the disclosure disclosed herein. While various embodiments are discussed, the disclosure encompasses all combinations of all of those embodiments.

[0147] While compositions, methods, and processes are described herein in terms of "comprising," "containing," "having," or "including" various components or steps, the compositions and methods can also "consist essentially of" or "consist of" the various components and steps. Unless specified otherwise, the phrase "consisting essentially of" does not exclude other steps, elements, or materials from being present in the compositions and methods, whether or not a specific reference to those steps, elements, or materials is made in the specification, as long as those steps, elements, or materials do not affect the basic and novel characteristics of the compositions and methods. In addition, it is not intended that any step, element, or material be indispensable to the practice of the present disclosure unless specifically designated as such in the specification.

[0148] All numerical values in the detailed description are modified by the term "about" the indicated value, considering experimental error and variations that would be expected by persons of ordinary skill in the art.

[0149] Many alterations, modifications, and variations will be apparent to those of ordinary skill in the art in light of the foregoing description, and it is to be understood that this has been described by way of example only and without any intent to limit the scope of the disclosure. When numerical lower limits and numerical upper limits are listed separately, ranges from any lower limit to any upper limit are contemplated.

Claims

1. A method of sequestering a contaminant compound from a polymer waste, comprising: at least thermally cracking a feedstock comprising a polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises a chlorine and / or chloride compound, wherein at least a portion of the chlorine and / or chloride compound is isolated into the coke, and wherein the coke comprises 0.01 wt% to 1 wt% of the chlorine and / or chloride compound; and separating at least a portion of the coking effluent to form a coking naphtha.

2. The method of claim 1, wherein the coking naphtha has a concentration of chlorine and / or chloride compound in an amount of about 1 wppm to about 0.5 wt%, a 2-3 ring aromatic compound content of about 0 wt% to about 5 wt%, and a sulfur content of about 750 ppm to about 2 wt%.

3. The method of any one of claims 1-2, wherein the polymer waste further comprises at least one contaminant selected from the group consisting of nitrogen, sulfur, aluminum, boron, calcium, chromium, cobalt, iron, manganese, magnesium, molybdenum, nickel, potassium, phosphorus, silicon, sodium, titanium, vanadium, and combinations thereof.

4. The method of claim 3, wherein the coke further comprises each of the at least one contaminant in an amount of about 0.01 wt% to about 1 wt%.

5. The method of any one of claims 1-4, wherein the coker feedstock comprises a heavy oil having a T10 distillation point of about 343°C to about 575°C.

6. The method of any one of claims 1-5, wherein the feedstock comprises the polymer waste in an amount of about 0.1 wt% to about 25 wt%.

7. The method of any one of claims 1-6, further comprising converting the coking naphtha to at least a polymer.

8. The method of claim 7, wherein at least a portion of the polymer is attributable to one or more polymers in the polymer waste, wherein the polymer comprises a recycled polymer.

9. The method of claim 8, wherein at least a portion of the polymer is an internationally certified recycled material according to the International Sustainability and Carbon Certification.

10. The method of any one of claims 1-9, wherein the coking effluent further comprises a coking gas, and wherein the coking gas comprises the chlorine and / or chloride compound in an amount of about 0 wt% to about 0.001 wt%, and / or wherein the coking effluent further comprises a coking gas oil and wherein the coking gas oil comprises the chlorine and / or chloride compound in an amount of about 0 wt% to about 0.001 wt%.

11. A method of sequestering a contaminant compound from a polymer waste, comprising: at least thermally cracking a feedstock comprising a polymer waste and a coker feedstock to at least produce coke and a coking effluent comprising hydrocarbons, wherein the polymer waste comprises at least a metal comprising titanium, wherein at least a portion of the metal is isolated into the coke, and wherein the coke comprises 0.01 wt% to 2 wt% of the metal; and separating at least a portion of the coking effluent to form a coking naphtha.

12. The method of claim 11, wherein the metal further comprises at least one additional metal selected from the group consisting of aluminum, calcium, magnesium, zinc, and combinations thereof, wherein the coke further comprises the additional metal in an amount of about 0.01 wt% to about 1 wt%.

13. A petroleum coke composition, comprising: at least 95 wt% carbon; chlorine and / or chloride compounds in an amount of about 0.01 wt% to about 1 wt%; titanium in an amount of about 0.01 wt% to about 1 wt%; aluminum in an amount of about 0.01 wt% to about 1 wt%; and vanadium in an amount of about 0.01 wt% to about 1 wt%.

14. The petroleum coke composition of claim 13, wherein at least a portion of the carbon is attributable to one or more polymers from a thermally cracked polymer waste.

15. The petroleum coke composition of claim 13, further comprising at least one contaminant selected from the group consisting of nitrogen, sulfur, boron, calcium, chromium, cobalt, iron, manganese, magnesium, molybdenum, nickel, potassium, phosphorus, silicon, sodium, and combinations thereof, in an amount of about 0.01 wt% to about 1 wt%.

Images