Systems and methods for reactive steam hydrolysis treatment of pyrolysis oil

Abstract

Systems and methods are presented for production, treatment, and processing of pyrolysis oil. An embodiment of one such system includes a vacuum distillation column configured to receive and vacuum distill pyrolysis oil to collect a naphtha cut at a temperature less than 120 degrees Celsius (°C), the naphtha cut having an organic chloride content. The system includes a reactive steam hydrolysis treatment zone including one or more reactive steam hydrolysis units configured to receive and perform reactive steam hydrolysis treatment of the naphtha cut to hydrolyze a substantial portion of the organic chloride content of the naphtha cut, thereby to yield a hydrolytically-treated naphtha cut.

Description

24CHEM0009-WO-ORD1SYSTEMS AND METHODS FOR REACTIVE STEAM HYDROLYSIS TREATMENT OF PYROLYSIS OILTECHNICAL FIELD

[0001] The present disclosure generally relates to systems and methods for treatment of pyrolysis oil derived from mixed plastic waste to remove organochloride contaminants. More specifically, the present disclosure relates to systems and methods for isolating a naphtha cut from pyrolysis oil, and then hydrolytically dechlorinating the naphtha cut using a reactive steam hydrolysis treatment, yielding an upgraded naphtha cut having a decreased organochloride content.BACKGROUND

[0002] Pyrolysis oil originates from the chemical recycling of mixed plastic waste (MPW). For example, pyrolysis oil can be formed by pyrolyzing MPW at sufficiently elevated temperatures (e.g., between 400 °C and 500 °C) under anaerobic conditions. MPW often contains polyvinyl chloride (PVC), among other polymers. Under the pyrolysis conditions, PVC can be converted into various organochloride species (e.g., alkyl chlorides). These organochloride species may release corrosive hydrogen chloride gas (HC1) during subsequent hydrotreatment and / or cracking, which can lead to undesirable corrosion issues in hydrotreatment and / or cracking reactors. Accordingly, there remains a need for improved techniques for dechlorinating pyrolysis oil.SUMMARY

[0003] Embodiments include systems and methods for production, treatment, and processing of pyrolysis oil. An embodiment of one such system includes a vacuum distillation column configured to receive and vacuum distill pyrolysis oil to collect a naphtha cut, the naphtha cut containing C4 to C12 hydrocarbons and an organic chloride content. The system includes a reactive steam hydrolysis treatment zone including one or more reactive steam hydrolysis units configured to receive and perform reactive steam hydrolysis treatment of the naphtha cut to hydrolyze a substantial portion of the organic chloride content of the naphtha cut, thereby to yield a hydrolytically -treated naphtha cut.

[0004] In some embodiments, the system includes a pyrolysis reactor configured to receive and pyrolyze mixed plastic waste, thereby to yield the pyrolysis oil. In some embodiments, the hydrolytically-treated naphtha cut contains 5 weight percent (wt. %) or less of the organic chloride24CHEM0009-WO-ORD2 content of the naphtha cut. In some embodiments, within the one or more reactive steam hydrolysis units, a temperature ranges from 120 degrees Celsius (°C) to 300 °C and a pressure ranges from 4 bar gauge (barg) to 40 barg during the reactive steam hydrolysis treatment, wherein a residence time of the naphtha cut within the one or more reactive steam hydrolysis units ranges from 1 minute to 60 minutes during the reactive steam hydrolysis treatment, and wherein a percentage of steam in a mixture of steam and naphtha cut within the one or more reactive steam hydrolysis units ranges from 10 wt. % to about 25 wt. %. In some embodiments, the one or more reactive steam hydrolysis units remain free of fouling after performing the reactive steam hydrolysis treatment. In some embodiments, the vacuum distillation column is configured vacuum distill the pyrolysis oil to collect the naphtha cut at a temperature less than 120 °C and at a pressure less than 1 millibar.

[0005] In some embodiments, the vacuum distillation column is further configured to collect a heavier cut from the vacuum distillation of the pyrolysis oil, the heavier cut containing C12 to C50 hydrocarbons. In some embodiments, the system includes a solvent extraction treatment zone configured to receive and perform solvent extraction treatment of the heavier cut, thereby to yield a solvent-extracted heavier cut. In some embodiments, the system includes a steam cracker configured to receive and steam crack the hydrolytically-treated naphtha cut, the solvent-extracted heavier cut, or both, thereby to yield hydrocarbon products. In some embodiments, the system includes a refinery configured to receive and refine the hydrolytically-treated naphtha cut, the solvent-extracted heavier cut, or both, thereby to yield hydrocarbon products.

[0006] An embodiment of one such method for hydrolytic treatment of pyrolysis oil includes the step of vacuum distilling the pyrolysis oil to collect a naphtha cut, the naphtha cut containing C4 to C12 hydrocarbons and an organic chloride content. The method includes the step of performing reactive steam hydrolysis treatment of the naphtha cut to hydrolyze at least 95 wt. % of the organic chloride content of the naphtha cut in the presence of steam, thereby to yield a hydrolytically- treated naphtha cut.

[0007] In some embodiment, performing the reactive steam hydrolysis treatment includes the step of contacting the naphtha cut with steam at a temperature ranging from about 120 °C to about 300 °C and a pressure ranging from about 4 barg to about 40 barg for a time period ranging from about 1 minute and about 60 minutes. In some embodiment, a percentage of steam in a mixture of steam and naphtha cut during the reactive steam hydrolysis treatment ranges from about 10 wt. %24CHEM0009-WO-ORD3 to about 25 wt. %. In some embodiment, vacuum distilling further includes the step of collecting a heavier cut, the heavier cut containing C12 to C50 hydrocarbons a second organic chloride content, and wherein the method further includes the step of performing a solvent extraction treatment of the heavier cut to extract a substantial portion of the second organic chloride content from the heavier cut, thereby to yield a solvent-extracted heavier cut. In some embodiment, the method includes the step of performing steam cracking or refining of the hydrolytically-treated naphtha cut, the solvent-extracted heavier cut, or both, without performing hydrotreatment of hydrolytically-treated naphtha cut or the solvent-extracted heavier cut. In some embodiment, the pyrolysis oil contains from 5 wt. % to 50 wt. % of the naphtha cut, and wherein the naphtha cut contains 70 wt. % of the organic chloride content of the pyrolysis oil.

[0008] Aspects and advantages of these exemplary embodiments and other embodiments, are discussed in detail herein. Moreover, it is to be understood that both the foregoing information and the following detailed description provide merely illustrative examples of various aspects and embodiments, and are intended to provide an overview or framework for understanding the nature and character of the claimed aspects and embodiments. Accordingly, these and other objects, along with advantages and features of the present disclosure, will become apparent through reference to the following description and the accompanying drawings. Furthermore, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and may exist in various combinations and permutations.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present disclosure, are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure, and together with the detailed description, serve to explain principles of the embodiments discussed herein. No attempt is made to show structural details of this disclosure in more detail than may be necessary for a fundamental understanding of the embodiments discussed herein and the various ways in which they may be practiced. According to common practice, the various features of the drawings discussed below are not necessarily drawn to scale. Dimensions of various features and elements in the drawings may be expanded or reduced to more clearly illustrate embodiments of the disclosure.24CHEM0009-WO-ORD4

[0010] FIG. 1A is a diagrammatic representation of a pyrolysis oil production, treatment, and processing system, according to an embodiment.

[0011] FIG. IB is a diagrammatic representation of a reactive steam hydrolysis treatment zone, according to an embodiment.

[0012] FIG. 1C is a diagrammatic representation of a reactive steam hydrolysis system, according to an embodiment.

[0013] FIG. ID is a diagrammatic representation of a solvent extraction treatment zone, according to an embodiment.

[0014] FIG. 2 is a diagrammatic representation of an embodiment of a method of operating the pyrolysis oil production, treatment, and processing system to convert mixed plastic waste (MPW) into useful hydrocarbon products, according to an embodiment.

[0015] FIG. 3 is a diagrammatic representation of a method of operating the reactive steam hydrolysis treatment zone to remove a substantial portion of the organic chloride content of the naphtha cut, according to an embodiment.

[0016] FIG. 4 is a diagrammatic representation of a method of operating the solvent extraction treatment zone to remove a substantial portion of the organic chloride content of the heavier cut, according to an embodiment.

[0017] FIG. 5 is a diagrammatic representation of an embodiment of a control system of the pyrolysis oil production, treatment, and processing system, according to an embodiment.DETAILED DESCRIPTION

[0018] The present disclosure describes various embodiments related to systems and methods for producing, treating, and processing pyrolysis oil. The description may use the phrases “in certain embodiments,” “in various embodiments,” “in an embodiment,” or “in embodiments,” which may each refer to one or more of the same or different embodiments. Furthermore, the terms “comprising,” “including,” “having,” and the like, as used with respect to embodiments of the present disclosure, are synonymous. The term “plurality” as used herein refers to two or more items or components. The terms “about” or “approximately” are defined as being close to as understood by one of ordinary skill in the art. In one non-limiting embodiment, these terms are defined to be within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.24CHEM0009-WO-ORD5

[0019] The terms “removing,” “removed,” “reducing,” “reduced,” or any variation thereof, when used in the claims and / or the specification includes any measurable decrease of one or more components in a mixture to achieve a desired result. The use of the words “a” or “an” when used in conjunction with any of the terms “comprising,” “including,” “containing,” or “having,” in the claims or the specification may mean “one,” but it is also consistent with the meaning of “one or more,” “at least one,” and “one or more than one.” The terms “wt. %”, “vol. %”, or “mol. %” refers to a weight, volume, or molar percentage of a component, respectively, based on the total weight, the total volume of material, or total moles, which includes the component. In a nonlimiting example, 10 grams of component in 100 grams of the material is 10 wt.% of component. As used herein, the term “zone” can refer to an area including one or more units and / or one or more sub-zones. Units can include one or more reactors or reactor vessels, separators, strippers, extraction columns, fractionation columns, heaters, exchangers, pipes, pumps, valves, compressors, sensors, and controllers. Additionally, a unit, such as a reactor, dryer, or vessel, can further include one or more zones or sub-zones that contain various equipment.

[0020] FIG. 1A is a diagrammatic representation of an embodiment of a pyrolysis oil production, treatment, and processing system 100. The system 100 generally converts batches of mixed plastic waste (MPW) 102 into pyrolysis oil 104, and then separates and treats the fractions of the pyrolysis oil 104 to reduce an organic chloride content of these fractions, prior to further processing to yield various useful hydrocarbon products 106. In some implementations, the MPW 102 consists of one or more chloride-containing polymers, while in other implementations, the MPW 102 includes a mixture of chloride-containing polymers and other polymers. Examples of chloride-containing polymers include polyvinyl chloride (PVC), poly vinylidene chloride (PVDC), chlorinated polyvinyl chloride (CPVC), other polychloroolefins, and mixtures thereof. In some embodiments, the hydrocarbon products 106 include olefins (e.g., ethylene, propylene), paraffins, or combinations thereof.

[0021] For the embodiment illustrated in FIG. 1A, the MPW 102 advances to the pyrolysis reactor 108 and is exposed to pyrolysis conditions to yield pyrolysis oil 104. For example, the pyrolysis conditions may include heating the MPW 102 to temperatures ranging from about 400 °C to about 500 °C under anaerobic conditions. Under these pyrolysis conditions, at least a portion of the chloride-containing polymers decompose to form various organic chloride species, such as24CHEM0009-WO-ORD6 chloroalcohols, alkyl chlorides and / or aromatic chlorides. These organic chloride species can subsequently release hydrogen chloride gas (HC1) during later processing (e.g., hydrotreating, cracking). Because HC1 is highly corrosive, it can corrode equipment when the pyrolysis oil 104 is subsequently refined or cracked. In some embodiments, the pyrolysis oil 104 may be produced at a pyrolysis reactor disposed first location before being transported to another location for further treatment and / or processing (e.g., hydrolytic dechlorination, hydrotreatment, and / or steam cracking).

[0022] With the foregoing in mind, the embodiment of the pyrolysis oil production, treatment, and processing system 100 illustrated in FIG. 1A includes a vacuum distillation column 110 that receives and distills the pyrolysis oil 104 under reduced pressure to yield at least a lighter, naphtha cut 112 and a heavier cut 114. For example, in certain embodiments, the naphtha cut 112 (also referred to herein as the light fraction) predominantly includes C4 to C12 hydrocarbons, while the heavier cut 114 (which may be referred to herein as the heavy fraction) predominantly includes C12 to Cso hydrocarbons. The pyrolysis oil 104 generally includes from about 5 wt. % to about 50 wt. % of the naphtha cut 112, with the remainder being the heavier cut 114. For example, in some embodiments, the pyrolysis oil 104 includes about 30 wt. % of the naphtha cut 112, with the remainder being the heavier cut 114. For the illustrated embodiment, the vacuum distillation column 110 includes sensors (e.g., temperature sensor 116, pressure sensors 118) and operational features (e.g., heating unit(s) 120, vacuum pump(s) 122) that are communicatively connected to the controller 124, such that the controller 124 can receive operational data from the vacuum distillation column 110 and provide control signals to control operation of the vacuum distillation column 110. The naphtha cut 112 is generally collected at a temperature less than 120 degrees Celsius (°C), such as from about 50 °C to about 90 °C, while the heavier cut 114 is what remains once the naphtha cut 112 has been removed from the pyrolysis oil 104. The pressure within the vacuum distillation column 110 may be less than 1 millibar (mbar), such as from about 0.1 mbar to about 0.5 mbar. In some embodiments, depending on the composition of the MPW 102, the pyrolysis oil 104 may include from about 310 part-per-million by weight (ppmw) to about 2000 ppmw organic chlorides. In some embodiments, depending on the organic chloride content of the pyrolysis oil 104, the naphtha cut 112 may include from about 900 ppmw to about 6000 ppmw organic chlorides. As such, in certain embodiments, the naphtha cut 112 may include about 70 wt.24CHEM0009-WO-ORD7% of the organic chloride content of the pyrolysis oil 104. In some embodiments, depending on the organic chloride content of the pyrolysis oil 104, the heavier cut 114 may include from about 5 ppmw to about 150 ppmw organic chlorides. As such, in certain embodiments, the naphtha cut 112 may include about 80 wt. % of the organic chloride content of the pyrolysis oil 104.

[0023] For the embodiment illustrated in FIG. 1A, the naphtha cut 112 is provided as input to a reactive steam hydrolysis treatment zone 126 for hydrolytic dechlorination treatment using steam delivered by a steam source 128 to remove or substantially reduce the organic chloride content of the naphtha cut 112, thereby yielding a hydrolytically-treated naphtha cut 130. The reactive steam hydrolysis treatment zone 126 is discussed in greater detail with respect to FIGS. IB and 1C, and the reactive steam hydrolysis treatment is discussed in greater detail with respect to FIG. 3. In general, the reactive steam hydrolysis treatment removes more than 95 % of the organic chloride content present within the naphtha cut 112. For an example embodiment, when the naphtha cut 112 includes an organic chloride content from about 900 ppmw to about 6000 ppmw, the hydrolytically -treated naphtha cut 130 may include an organic chloride content between about 45 ppmw to about 300 ppmw. For the embodiment illustrated in FIG. 1, the heavier cut 114 is provided as input to a solvent extraction treatment zone 132 for solvent extraction treatment using a solvent to remove or substantially reduce the organic chloride content of the heavier cut 114, thereby yielding a solvent-extracted heavier cut 134. In some embodiments, the solvent extraction treatment may also remove other un desired components from the heavier cut 114, such as nitrogencontaining compounds and / or metals. The solvent extraction treatment zone 132 is discussed in greater detail with respect to FIG. ID, and the solvent extraction treatment is discussed in greater detail with respect to FIG. 4. In general, the solvent extraction treatment removes more than 70 % of the organic chloride content present within the heavier cut 114.

[0024] For the embodiments disclosed herein, it was experimentally determined that it is advantageous to perform vacuum distillation of the pyrolysis oil 104 to isolate the naphtha cut 112 and then perform reactive steam hydrolytic treatment of the naphtha cut 112, as opposed to performing reactive steam hydrolytic treatment on the pyrolysis oil 104 directly. In particular, model experiments performed at laboratory scale surprisingly indicated that performing reactive steam hydrolytic treatment on the pyrolysis oil 104 directly results in considerable fouling. While not wishing to be bound by theory, it is believed that this fouling is formed because of (i) reactions24CHEM0009-WO-ORD8 of diolefins and olefins in the pyrolysis oil 104 that form larger molecular species that deposit and / or (ii) oxidation of nitrogen containing components that lead to polar species being formed that precipitate, and that elevated temperatures increase the speed of both processes. In contrast, when the reactive steam hydrolytic treatment was instead performed on the naphtha cut 112, surprisingly no fouling of the reactive steam hydrolysis vessel was observed. It may be appreciated that, by performing solvent extraction only on the heavier cut 114, less solvent is consumed or used than would be if the pyrolysis oil 104 or both the naphtha cut 112 and the heavier cut 114 received solvent extraction treatment.

[0025] It is further presently recognized that, unlike other reactions dechlorination reactions, the disclosed hydrolytic dechlorination process specifically results in organic chlorides (e.g., alkyl chlorides) being converted into corresponding organic alcohols (e.g., alkyl alcohols). This is in contrast with a hydrodechlorination reaction (also known as dehydrochlorination reaction), in which, for example, an alkyl chloride loses both a proton and a chloride group to form an alkene (also known as an olefin). More specifically, unlike other dechlorination reactions, the disclosed hydrolytic dechlorination process involves the use of steam / water, and optionally a base (e.g., an amine or ammonium species), to form a nucleophilic hydroxide species ('OH), which displaces chloride from the organic chloride structure, resulting in the organic alcohol, as illustrated in Scheme 1 for an example alkyl chloride species. While not wishing to be bound by theory, it is believed that the presence of the organic alcohols (e.g., alkyl alcohols) in the hydrolytically-treated naphtha cut 130 can desirably decrease the rate of coke formation within later processing steps (e.g., hydrotreatment, steam or fluid catalytic cracking) compared to the olefin products of other dechlorination processes. Additionally, it is believed that relative to the alkenes formed from other dechlorination reactions, the organic alcohols produced by the hydrolytic dechlorination are inactive when the hydrolytically -treated naphtha cut 130 is heated, while alkenes are reactive and promote or contribute to undesirable fouling. Therefore, the organic alcohols produced by the hydrolytic dechlorination increase the stability of the pyrolysis oil, which results in substantially less fouling than the alkenes formed using other dechlorination techniques. As noted, the hydrolytic dechlorination reaction further produces HC1 gas, which at least partially dissolved in water to form aqueous hydrochloric acid (HC1 aq.).

[0026] Scheme 1 : Reactive steam hydrolytic dechlorination reaction.24CHEM0009-WO-ORD

[0027] For the embodiment illustrated in FIG. 1A, the hydrolytically-treated naphtha cut 130 and the solvent-extracted heavier cut 134 proceed to further processing. In the illustrated embodiment, the hydrolytically -treated naphtha cut 130 and the solvent-extracted heavier cut 134 may be separately or together provided as input to a steam cracker 136 or a refinery 138 to convert and / or purify the feeds to yield the hydrocarbon products 106. In some embodiments, the hydrolytically-treated naphtha cut 130 and / or the solvent-extracted heavier cut 134 have a sufficiently low organic chloride content that the stream(s) may be provided for steam cracking or refining without hydro treatment, desirably reducing the complexity and operational costs of the system 100, while also reducing the cost of producing the hydrocarbon products 106. In an example embodiment, the hydrolytically-treated naphtha cut 130 may proceed to steam cracking, while the solvent-extracted heavier cut 134 proceeds to refining. In some embodiments, the hydrolytically -treated naphtha cut 130 and the solvent- extracted heavier cut 134 may be separately or together transported to another location for steam cracking and / or refining. It may be appreciated that the reduced organic chloride content of the hydrolytically-treated naphtha cut 130 and / or the solvent-extracted heavier cut 134 advantageously reduces or eliminates gum formation within these fluids for an extended period of time (e.g., 2 months or more) during storage or transport. For some embodiments in which the reactive steam hydrolysis treatment zone 126 and the steam cracker 136 are operated at the same location, a common steam source 128 may provide input steam to both the reactive steam hydrolysis treatment zone 126 and the steam cracker 136, which may desirably reduce system complexity, construction costs, and operational costs. In some such embodiments, the steam may be dilution steam that is alkalized with one or more amine compounds, which can advantageously enable higher conversion of organic chloride species present in the naphtha cut 112 into HC1 during the reactive steam hydrolysis treatment.

[0028] FIG. IB is a diagrammatic representation of an embodiment of the reactive steam hydrolysis treatment zone 126. For the illustrated embodiment, the naphtha cut 112 produced by vacuum distillation of the pyrolysis oil is provided as input to a first organic chloride analyzer24CHEM0009-WO-ORD10150A that is communicatively connected to the controller 124. The first organic chloride analyzer 150A measures the organic chloride content of the naphtha cut 112 and provides these measurements to the controller 124. In some embodiments, the first organic chloride analyzer 150A is an analyzer (e.g., gas chromatography -halogen-specific detector (GC-XSD)) that measures the types (e.g., polar and medium-polarity) and relative amounts of organic chloride species present within the naphtha cut 112. Using this information, the controller 124 can determine a suitable and efficient reactive steam hydrolysis treatment to remove a substantial portion of the organic chloride content, as discussed in greater detail below.

[0029] For the embodiment illustrated in FIG. IB, the analyzed naphtha cut 112 is introduced into the reactive steam hydrolysis system 152 along with steam from the steam source 128. The illustrated embodiment of the reactive steam hydrolysis system 152 includes a number of reactive steam hydrolysis units 154 (e.g., 154A, 154B, 154C, and 154D). In some embodiments, the reactive steam hydrolysis system 152 includes fewer or additional reactive steam hydrolysis units 154, and some of the reactive steam hydrolysis units 154 may be coupled together in series or in parallel, as discussed with respect to FIG. 1C. In some embodiments, one or more of the reactive steam hydrolysis units 154 may remain online while one or more of the other reactive steam hydrolysis units 154 are taken offline for maintenance or repair. In general, the naphtha cut 112 and the steam are routed through at least one of the reactive steam hydrolysis units 154 under suitable conditions to instigate hydrolytic dechlorination of organic chloride species present within the naphtha cut 112, thereby to yield a mixture of hydrolytically -treated naphtha cut and HCl-rich steam / water.

[0030] For the embodiment illustrated in FIG. IB, the mixture of hydrolytically -treated naphtha cut and HCl-rich steam / water is provided as input to the separation unit 156 for separation. For example, in some embodiments, the separation unit 156 may be a centrifuge or decanter. The separated HCl-rich steam / water 158 is provided to a water treatment unit 160 for neutralization and chloride removal to yield recovered water 162, which can be recycled to the steam source 128. The separated hydrolytically-treated naphtha cut is provided as input to a second organic chloride analyzer 150B that is communicatively connected to the controller 124. The second organic chloride analyzer 150B may determine the types (e.g., polar and medium-polarity) and relative amounts of organic chloride species, or the total chloride content, remaining in the hydrolytically-24CHEM0009-WO-ORD11 treated naphtha cut after an initial reactive steam hydrolysis treatment. Responsive to the controller 124 determining that the amount of one or more organic chloride species remains above a predetermined threshold value (e.g., 5 wt. %), the controller 124 may provide suitable control signals to one or more valves 164 to route the hydrolytically-treated naphtha cut 130 back to the reactive steam hydrolysis system 152 for further reactive steam hydrolysis treatment. Responsive to the controller 124 determining that the amount of one or more organic chloride species is less than or equal to the predetermined threshold value, the controller 124 may provide suitable control signals to one or more valves 164 to route the hydrolytically-treated naphtha cut 130 to the steam cracker 136, the refinery 138, or to storage or transport vessels, as noted above.

[0031] FIG. 1C is a diagrammatic representation of an embodiment of the reactive steam hydrolysis system 152. For the illustrated embodiment, the reactive steam hydrolysis system 152 includes a first reactive steam hydrolysis unit 154A operated at a first set of reaction conditions and a second reactive steam hydrolysis unit 154B operated at a second set of reaction conditions. In some embodiments, the first set of reaction conditions and the second set of reaction conditions are the same and the reactive steam hydrolysis units 154A and 154B are operated in parallel to hydrolytically treat the naphtha cut 112 at higher volumes. In some embodiments, the first set of reaction conditions and the second set of reaction conditions are different to target hydrolytic treatment of particular organic chloride species, and the controller 124 may conditionally route the naphtha cut 112 to either of the reactive steam hydrolysis units 154A or 154B based on the organic chloride content and species present within the naphtha cut 112. In some embodiments, the first set of reaction conditions and the second set of reaction conditions are different to target hydrolytic treatment of particular organic chloride species, and the controller 124 may conditionally route the naphtha cut 112 to the first reactive steam hydrolysis unit 154A and then to the second reactive steam hydrolysis unit 154B based on the organic chloride content and species present within the naphtha cut 112.

[0032] For the embodiment illustrated in FIG. 1C, the reactive steam hydrolysis system 152 includes any suitable number valves 180, including valves 180A, 180B, 180C, and 180D, that are communicatively connected to the controller 124. Based on the reactive steam hydrolysis treatment determined by the controller 124 in accordance with the analysis of the naphtha cut 112, the controller 124 provides suitable control signals to route the naphtha cut through the first reactive24CHEM0009-WO-ORD12 steam hydrolysis unit 154A and / or a second reactive steam hydrolysis unit 154B one or more times. More specifically, the controller 124 may provide suitable control signals to the valve 180A and / or 180B to enable the naphtha cut 112 and steam from the steam source 128 to enter the reactive steam hydrolysis unit 154A and / or 154B. The controller 124 may provide control signals to the valve 180C to route the resulting mixture 182 of hydrolytically-treated naphtha cut and steam / water exiting the first reactive steam hydrolysis unit 154A: (i) along the pipeline 184 back into the reactive steam hydrolysis unit 154A for further treatment, (ii) along pipeline 186 into the reactive steam hydrolysis unit 154B for further treatment, or (iii) along pipeline 188 to advance to the separation unit 156, as shown in FIG. IB. The controller 124 may provide control signals to the valve 180D to route the resulting mixture 182 of hydrolytically-treated naphtha cut and steam / water: (i) along the pipeline 190 back into the reactive steam hydrolysis unit 154B for further treatment, or (ii) along pipeline 192 to advance to the separation unit 156, as shown in FIG. IB. As such, the valves 180 generally enable the controller 124 to operate the reactive steam hydrolysis units 154 individually, in series, or in parallel, with single or multiple passes through each unit in each arrangement, depending on the composition of the naphtha cut 112 and the desired throughput of the reactive steam hydrolysis system 152. Additionally, the controller 124 can provide suitable control signals to the valves 180 to operate the reactive steam hydrolysis units 154 in a batch processing mode or in a continuous processing mode. Furthermore, the controller 124 can make modifications on-the-fly to modify the flow of the naphtha cut 112 through the reactive steam hydrolysis system 152 based on the effectiveness of the reactive steam hydrolysis treatment (e.g., as measured by the second organic chloride analyzer 150B) and / or based on changes in the composition of the naphtha cut 112.

[0033] For the embodiment illustrated in FIG. 1C, the reactive steam hydrolysis units 154 each include respective sensors, including a temperature sensor 194 and a pressure sensor 196, that are communicatively connected to the controller 124 to provide measurements of conditions within each unit. In some embodiments, the reactive steam hydrolysis units 154 each include a respective heater 198 is communicatively connected to the controller 124 to receive control signals to adjust or maintain the temperature within each unit during operation. In some embodiments, the steam source 128 may instead by a liquid water source, and the respective heater 198 of each of the steam24CHEM0009-WO-ORD13 hydrolysis units 154 may be responsible for converting the liquid water into steam to instigate the hydrolytic dechlorination reaction within each unit.

[0034] In some embodiments, within the reactive steam hydrolysis units 154 during a treatment operation, the temperatures range from about 120 °C to about 300 °C (e.g., from about 150 °C to about 300 °C) as a result of heating from the steam and / or the heater 198, and the pressures range from about 4 bar gauge (barg) to about 40 barg. The residence time for the naphtha cut 112 within the reactive steam hydrolysis units 154 may range from about 1 minute to about 60 minutes, depending on the organic chloride content and composition within the naphtha cut 112. The percentage of steam / water in the mixture of steam / water and naphtha cut within the reactive steam hydrolysis units 154 may range from about 10 wt. % steam / water to about 25 wt. % steam / water. In some embodiments, the steam / water contains an amount (e.g., from about 0.002 wt. % to about 1 wt. %) a water-soluble, basic amine or ammonium species (e.g., triethyl amine, ammonium hydroxide) to enhance the reactive steam hydrolysis treatment and / or capture released HC1. In an example embodiment in which the naphtha cut 112 contains mostly or entirely polar organic chloride species, one or more of the reactive steam hydrolysis units 154 may be maintained at the lower end of the operational temperature range (e.g., around 120 °C), which effectively hydrolytically converts these polar organic chloride species while desirably limiting energy consumption. In some embodiments, the first reactive steam hydrolysis unit 154A may be operated at a lower temperature range (e.g., from around 120 °C to around 150 °C) and the second reactive steam hydrolysis unit 154B may be operated at a higher temperature (e.g., from around 150 °C to around 300 °C), and the naphtha cut 112 may be serially treated within the two reactive steam hydrolysis units 154 in a two-stage treatment - first passing through the first reactive steam hydrolysis unit 154A one or more times to treat and remove polar organic chlorides, and then passing through the second reactive steam hydrolysis unit 154B one or more times to remove medium-polarity organic chlorides from the naphtha cut, which desirably limits the amount of HC1 released in each treatment stage and enables optimization of conditions, including residence time, within each treatment stage.

[0035] FIG. ID is a diagrammatic representation of an embodiment of the solvent extraction treatment zone 132. For the illustrated embodiment, the solvent extraction treatment zone 132 includes a solvent extraction unit 220, a separation unit 222, and a solvent treatment unit 224, each24CHEM0009-WO-ORD14 of which is communicatively connected to the controller 124 to receive control signals to control and modify operation. The heavier cut 114 separated by the vacuum distillation column 110 is provided as input to the solvent extraction unit 220 along with a polar solvent. In some embodiments, the polar solvent may include, but is not limited to: dimethylsulfoxide (DMSO), N- methylpyrrolidone (NMP), dimethylformamide (DMF), ethylene glycol, water, or a combination thereof. For example, in an embodiment, the solvent extraction operation may be performed using water as the polar solvent at a ratio of water to pyrolysis oil of 1 :2 at a temperature from about 10 °C to about 80 °C, which may remove about 90% or more of chloroalcohols (e.g., chloroethanol) from the pyrolysis oil. During the solvent extraction operation, the medium-polarity chlorinated species, and potentially certain nitrogen-containing species, are dissolved within the denser polar solvent layer, which is separated from the less-dense, purified pyrolysis oil. A mixture of the solvent-extracted heavier cut and the extraction solvent are provided as input to a separation unit 222 that separates the two components. For example, in some embodiments, the separation unit 222 may be a centrifuge or decanter. As illustrated, the extraction solvent may be subsequently purified by the solvent treatment unit 224 to remove the dissolved species and recycled in another solvent extraction operation to reduce operational cost and reduce waste. The solvent-extracted heavier cut 226 is subsequently routed to the steam cracker 136, the refinery 138, or to storage or transport vessels, as noted above.

[0036] FIG. 2 is a diagrammatic representation of an embodiment of a method 240 of operating the pyrolysis oil production, treatment, and processing system 100 to convert mixed plastic waste (MPW) into useful hydrocarbon products. The method 240 is discussed with reference to elements illustrated in FIGS. 1A-D. In other embodiments, the method 240 may include additional steps, omitted steps, repeated steps, and so forth, relative to the embodiment illustrated in FIG. 2. In some embodiments, one or more of the steps of the method 240 may be stored as instructions in a memory and executed by a processor of the controller 124.

[0037] For the embodiment illustrated in FIG. 2, the method 240 begins with the step 242 of pyrolyzing the MPW 102 in the pyrolysis reactor 108 to produce pyrolysis oil 104. The method 240 continues with the step 244 of performing a vacuum distillation of the pyrolysis oil using the vacuum distillation column 110 to yield the lighter, naphtha cut 112 and the heavier cut 114. The naphtha cut 112 advances to the reactive steam hydrolysis treatment zone 126, and at step 246,24CHEM0009-WO-ORD15 reactive steam hydrolysis treatment is performed on the naphtha cut 112, thereby to yield the hydrolytically-treated naphtha cut 130. Separately, the heavier cut 114 advances to the solvent extraction treatment zone 132, and at step 248, solvent extraction treatment is performed on the heavier cut, thereby to yield the solvent-extracted heavier cut 134. The method 240 concludes with the steps 250 and 252, in which the hydrolytically-treated naphtha cut 130 and the solvent- extracted heavier cut 134 advance, individually or in combination, to the steam cracker 136 for steam cracking and / or to the refinery 138 for refinement.

[0038] FIG. 3 is a diagrammatic representation of an embodiment of a method 300 of operating the reactive steam hydrolysis treatment zone 126 to remove a substantial portion of the organic chloride content of the naphtha cut 112. The method 300 is discussed with reference to elements illustrated in FIGS. 1A-D. In other embodiments, the method 300 may include additional steps, omitted steps, repeated steps, and so forth, relative to the embodiment illustrated in FIG. 3. In some embodiments, one or more of the steps of the method 300 may be stored as instructions (e.g., a reactive steam hydrolysis treatment module) in a memory and executed by a processor of the controller 124.

[0039] For the embodiment illustrated in FIG. 3, the method 300 begins with the step 302 of the controller 124 determining, based on an analysis of the naphtha cut by the first organic chloride analyzer 150 A, respective amounts of organochloride species present within the naphtha cut 112. The method 300 continues with the step 304 of the controller 124 determining reaction conditions (e.g., reaction temperatures, pressures, naphtha to water ratios, residence times) for a reactive steam hydrolysis treatment of the naphtha cut 112 based on the respective amounts of organochloride species present within the naphtha cut. The method 300 continues with the step 304 of the controller 124 providing suitable control signals to the valves 180 and the reactive steam hydrolysis units 154 to combine the naphtha cut 112 with steam in one or more reactive steam hydrolysis units 154 under the determined reaction conditions to yield a mixture 182 of hydrolytically -treated naphtha cut and HCl-rich steam / water.

[0040] For the embodiment illustrated in FIG. 3, the method 300 continues with the step 308 of the controller 124 providing suitable control signals to the separation unit 156 to separate the hydrolytically-treated naphtha cut 130 from the HCl-rich steam / water 158. The method 300 includes the step 310 of providing suitable control signals to introduce the HCl-rich steam / water24CHEM0009-WO-ORD16158 to the water treatment unit 160 for treatment and recovery of water, which can then be recycled in some embodiments. The method 300 includes the step 312 of the controller 124 determining, based on an analysis of the hydrolytically-treated naphtha cut 130 by the second organic chloride analyzer 150B, a chloride content of the hydrolytically-treated naphtha cut 130. At step 314, responsive to the controller 124 determining that the chloride content is not less than a predefined threshold value (e.g., 5 wt. %), the controller 124 returns to step 306 and provides suitable control signals to route the hydrolytically-treated naphtha cut 130 back to the reactive steam hydrolysis units 154 for additional reactive steam hydrolysis treatment. After one or more cycles through steps 306, 308, and 312, the controller 124 determines, at step 314, that the chloride content is less than the predefined threshold value. Responsive to this determination, and at step 316, the controller 124 provides suitable control signals to provide the hydrolytically-treated naphtha cut 130 to the steam cracker 136 for steam cracking and / or to the refinery 138 for refining, thereby to yield the hydrocarbon products 106.

[0041] FIG. 4 is a diagrammatic representation of an embodiment of a method 400 of operating the solvent extraction treatment zone 132 to remove a substantial portion of the organic chloride content of the heavier cut 114. The method 400 is discussed with reference to elements illustrated in FIGS. 1A-D. In other embodiments, the method 400 may include additional steps, omitted steps, repeated steps, and so forth, relative to the embodiment illustrated in FIG. 4. In some embodiments, one or more of the steps of the method 400 may be stored as instructions in a memory and executed by a processor of the controller 124.

[0042] For the embodiment illustrated in FIG. 4, the method 400 begins with the step 402 of combining the heavier cut 114 with solvent in the solvent extraction unit 220 to yield a mixture of solvent-extracted heavier cut and an impurity-rich solvent. The method 400 continues with the step 404 of separating the solvent-extracted heavier cut from the impurity-rich solvent using the separation unit 222. The method includes the step 406 of providing the impurity-rich solvent to a solvent treatment unit 224 for impurity extraction and solvent recovery. The method also includes the step 408 of providing the solvent-extracted heavier cut 226 to the steam cracker 136 for steam cracking and / or to the refinery 138 for refining, thereby to yield the hydrocarbon products 106.

[0043] FIG. 5 is a diagrammatic representation of an embodiment of a control system 500 of the pyrolysis oil production, treatment, and processing system 100. In some examples, the control24CHEM0009-WO-ORD17 system 500 includes at least the controller 124. While described herein as a controller, it may be appreciated by those skilled in the art that, in other embodiments, the controller 124 may be or include any suitable computing system, such as a desktop, laptop, or tablet computing device. Additionally, while the control system 500 is illustrated and described as including a single controller 124, in some embodiments, the operation of the controller may instead be implemented through use of a plurality of controllers of the control system 500 in signal communication with one another, e.g., distributed, in series, or supervisory to sub-component controllers, among others, as will be understood by those skilled in the art.

[0044] The controller 124 of various examples disclosed herein includes one or more processors, such as processor 502, as well as a memory or machine-readable storage medium, such as memory 504. As used herein, a “machine-readable storage medium” may be, for example, any electronic, magnetic, optical, or other physical storage apparatus to contain or store information such as executable instructions, data, and the like. For example, any machine-readable storage medium described herein may be any of random-access memory (RAM), volatile memory, non-volatile memory, flash memory, a storage drive, a hard drive, a solid-state drive, any type of storage disc, and the like, or a combination thereof. The memory 504 stores or includes instructions executable by the processor 502. As used herein, a “processor” includes, for example, one processor or multiple processors included in a single device or distributed across multiple computing devices. The processor 502 may be at least one of a central processing unit (CPU), a semiconductor-based microprocessor, a graphics processing unit (GPU), a field-programmable gate array (FPGA) to retrieve and execute instructions, a real-time processor (RTP), other electronic circuitry suitable for the retrieval and execution instructions stored on a machine-readable storage medium, or a combination thereof.

[0045] The controller 124 includes an I / O interface 506 that enables the controller to be in signal communication with other components associated with the pyrolysis oil production, treatment, and processing system 100. For example, these components may include components of the vacuum distillation column 110, such as temperature sensor(s) 116, pressure sensor(s) 118, vacuum pump(s) 122 and heating unit(s) 120, as discussed above with respect to FIG. 1A. The components may include components of the reactive steam hydrolysis treatment zone 126, such as the temperature sensor(s) 194, the pressure sensor(s) 196, the organic chloride analyzers 150, the24CHEM0009-WO-ORD18 valves 180, and the heater(s) 198. As used herein, “signal communication” refers to electric communication such as hard wiring two components together or wireless communication, as understood by those skilled in the art. For example, wireless communication may be Wi-Fi®, Bluetooth®, ZigBee, or forms of near field communications, as will be understood by those skilled in the art. In addition, signal communication may include one or more intermediate controllers or relays disposed between elements that are in signal communication with one another.

[0046] For the embodiment illustrated in FIG. 5, the memory 504 of the controller 124 includes instructions executed by the processor 502 to facilitate the production, treatment, and processing of pyrolysis oil, according to the examples disclosed herein. For the illustrated embodiment, the instructions include instructions of a vacuum distillation control module 508 that controls and monitors operation of the vacuum distillation column 110, as discussed herein, to separate the naphtha cut 112 and heavier cut 114 from the pyrolysis oil 104. The instructions also include instructions of a reactive steam hydrolysis treatment control module 510 that controls and monitors operation of the reactive steam hydrolysis treatment zone 126, for example, in accordance with the method 300 of FIG. 3. It may be appreciated that the modules 508 and 510 are merely shown as examples, and in other embodiments, the memory 504 may store other control modules, such as a pyrolysis control module that monitors and controls operation of the pyrolysis reactor 108, a solvent extraction control module that monitors and controls operation of the solvent extraction treatment zone 132, a steam cracker control module that monitors and controls operation of the steam cracker 136, a refinery control module that monitors and controls operation of the refinery 138, and so forth.

[0047] Other objects, features, and advantages of the disclosure will become apparent from the foregoing figures, detailed description, and examples. It should be understood, however, that the figures, detailed description, and examples, while indicating specific embodiments of the disclosure, are given by way of illustration only and are not meant to be limiting. Additionally, it is contemplated that changes and modifications within the spirit and scope of the disclosure will become apparent to those skilled in the art from the detailed description. In further embodiments, features from specific embodiments may be combined with features from other embodiments. For example, features from one embodiment may be combined with features from any of the other24CHEM0009-WO-ORD19 embodiments. In further embodiments, additional features may be added to the specific embodiments described herein.

Claims

24CHEM0009-WO-ORD20CLAIMSWhat is claimed is:

1. A system comprising: a vacuum distillation column configured to receive and vacuum distill pyrolysis oil to collect a naphtha cut, the naphtha cut containing C4 to C12 hydrocarbons and an organic chloride content; and a reactive steam hydrolysis treatment zone comprising one or more reactive steam hydrolysis units configured to receive and perform reactive steam hydrolysis treatment of the naphtha cut to hydrolyze a substantial portion of the organic chloride content of the naphtha cut, thereby to yield a hydrolytically-treated naphtha cut.

2. The system of claim 1 , comprising a pyrolysis reactor configured to receive and pyrolyze mixed plastic waste, thereby to yield the pyrolysis oil.

3. The system of any of claims 1 or 2, wherein the hydrolytically -treated naphtha cut contains 5 weight percent (wt. %) or less of the organic chloride content of the naphtha cut.

4. The system of any of claims 1-3, wherein, within the one or more reactive steam hydrolysis units, a temperature ranges from 120 degrees Celsius (°C) to 300 °C and a pressure ranges from 4 bar gauge (barg) to 40 barg during the reactive steam hydrolysis treatment, wherein a residence time of the naphtha cut within the one or more reactive steam hydrolysis units ranges from 1 minute to 60 minutes during the reactive steam hydrolysis treatment, and wherein a percentage of steam in a mixture of steam and naphtha cut within the one or more reactive steam hydrolysis units ranges from 10 wt. % to about 25 wt. %.

5. The system of any of claims 1-4, wherein the one or more reactive steam hydrolysis units remain free of fouling after performing the reactive steam hydrolysis treatment.

6. The system of any of claims 1-5, wherein the vacuum distillation column is configured vacuum24CHEM0009-WO-ORD21 distill the pyrolysis oil to collect the naphtha cut at a temperature less than 120 °C and at a pressure less than 1 millibar.

7. The system of any of claims 1-6, wherein the vacuum distillation column is further configured to collect a heavier cut from the vacuum distillation of the pyrolysis oil, the heavier cut containing C12 to Cso hydrocarbons, and wherein the system comprises a solvent extraction treatment zone configured to receive and perform solvent extraction treatment of the heavier cut, thereby to yield a solvent-extracted heavier cut.

8. The system of any of claims 1-7, comprising a steam cracker configured to receive and steam crack the hydrolytically-treated naphtha cut, the solvent-extracted heavier cut, or both, thereby to yield hydrocarbon products.

9. The system of any of claims 1-7, comprising a refinery configured to receive and refine the hydrolytically-treated naphtha cut, the solvent-extracted heavier cut, or both, thereby to yield hydrocarbon products.

10. A method for hydrolytic treatment of pyrolysis oil, the method comprising: vacuum distilling the pyrolysis oil to collect a naphtha cut, the naphtha cut containing C4 to C12 hydrocarbons and an organic chloride content; and performing reactive steam hydrolysis treatment of the naphtha cut to hydrolyze at least 95 weight percent (wt. %) of the organic chloride content of the naphtha cut in the presence of steam, thereby to yield a hydrolytically -treated naphtha cut.

11. The method of claim 10, wherein performing the reactive steam hydrolysis treatment comprises contacting the naphtha cut with steam at a temperature ranging from about 120 degrees Celsius (°C) to about 300 °C and a pressure ranging from about 4 bar gauge (barg) to about 40 barg for a time period ranging from about 1 minute and about 60 minutes.

12. The method of any of claims 10 or 11, wherein a percentage of steam in a mixture of steam24CHEMOOQ9-WO-ORD22 and naphtha cut during the reactive steam hydrolysis treatment ranges from about 10 weight percent (wt. %) to about 25 wt. %.

13. The method of any of claims 10-12, wherein vacuum distilling further comprises collecting a heavier cut, the heavier cut containing C12 to C50 hydrocarbons a second organic chloride content, and wherein the method further comprises performing a solvent extraction treatment of the heavier cut to extract a substantial portion of the second organic chloride content from the heavier cut, thereby to yield a solvent-extracted heavier cut.

14. The method of any of claims 10-13, comprising performing steam cracking or refining of the hydrolytically-treated naphtha cut, the solvent-extracted heavier cut, or both, without performing hydrotreatment of hydrolytically -treated naphtha cut or the solvent-extracted heavier cut.

15. The method of any of claims 10-14, wherein the pyrolysis oil contains from 5 wt. % to 50 wt. % of the naphtha cut, and wherein the naphtha cut contains 70 wt. % of the organic chloride content of the pyrolysis oil.

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