Patent Description:
The present invention generally relates to methods for producing high-value chemicals. More specifically, the present invention relates to methods for producing high-value chemicals from plastic-derived oil and used lubricating oil.

High value chemicals, including light olefins (C<NUM> to C<NUM> olefins) and BTX (benzene, toluene, and xylene), are generally produced from crude oil fractions. Light olefins (C<NUM> to C<NUM> olefins) are building blocks for many chemical processes. Light olefins are used to produce polyethylene, polypropylene, ethylene oxide, ethylene chloride, propylene oxide, and acrylic acid, which, in turn, are used in a wide variety of industries such as the plastic processing, construction, textile, and automotive industries. Generally, light olefins are produced by steam cracking naphtha and dehydrogenating paraffin.

BTX is a group of aromatics that is used in many different areas of the chemical industry, especially the plastic and polymer sectors. For instance, benzene is a precursor for producing polystyrene, phenolic resins, polycarbonate, and nylon. Toluene is used for producing polyurethane and as a gasoline component. Xylene is feedstock for producing polyester fibers and phthalic anhydride. In the petrochemical industry, benzene, toluene, and xylene are conventionally produced by catalytic reforming of naphtha.

Over the last few decades, the demand for both light olefins and BTX has been consistently increasing. Shortage of the feedstocks for producing light olefins and BTX has become a long-term concern. A few alternative feedstocks (e.g., propane) are currently used to produce light olefins. However, propane is used to produce propylene via catalytic dehydrogenation, which requires both high capital and operational expenditure. Furthermore, catalytic dehydrogenation generally requires high purity feedstocks of paraffins for producing only the corresponding olefins, which could further increase the production cost.

<CIT>, which discloses a process for the simultaneous conversion of waste lubricating oil and pyrolysis oil derived from organic waste to produce a synthetic crude oil by means of contacting the combined feed with a hot hydrogen-rich gaseous stream to increase the temperature of the combined feed to vaporize at least a portion of the distillable organic compounds contained therein which is immediately hydrogenated in a hydrogenation reaction zone. The resulting effluent from the hydrogenation reaction zone is then introduced into a hydroprocessing zone to produce higher hydrogen-content hydrocarbons and to remove heterogeneous components such as sulfur, oxygen, nitrogen and halide, for example. The resulting effluent is cooled and partially condensed to produce a gaseous stream containing hydrogen and gaseous water-soluble inorganic compounds and a liquid stream containing hydrocarbon compounds. The gaseous stream is scrubbed to remove the gaseous water-soluble organic compounds and to thereby produce a hydrogen-rich gaseous recycle stream. This reference describes production of a synthetic crude and does not teach or suggest production of light olefins and/or BTX.

<CIT> relates to the treatment of hydrocarbon streams resulting from pyrolysis of waste plastics for use in downstream processes. <CIT> relates to the production of hydrocarbon streams from mixed plastics via processes which include pyrolysis, hydroprocessing, hydrodealkylation, and steam cracking. <CIT> relates to the production of high-value chemicals, such as olefins and aromatic hydrocabons, from mixed plastics via processes which include pyrolysis, and gas steam cracking and liquid steam cracking.

Overall, while the methods of producing high-value petrochemicals exist, the need for improvements in this field persists in light of at least the aforementioned drawbacks for the conventional methods.

A solution to at least some of the above mentioned problems associated with methods of producing one or more olefins has been discovered. The solution resides in a method of producing light olefins using plastic derived oil and used lubricating oil as the feedstocks. Because the discovered method provides an alternative feedstock for producing light olefins and/or BTX, it addresses the long-term concerns regarding feedstock shortage. Furthermore, the feedstocks used in the discovered method are low cost and/or recycled material, thereby reducing the impact on the environment and minimizing the cost for feedstocks compared to conventional methods. Additionally, the method can be conducted in a system that can be integrated within the existing light olefins and/or BTX production systems, thereby reducing the capital expenditure compared to conventional methods that include catalytic dehydrogenation of paraffins. Therefore, the method of the present invention provides a technical solution to at least some of the problems associated with the conventional methods for producing light olefins and/or BTX.

The invention relates to a method of producing one or more olefins, as defined in the appended claims.

The terms "wt. %" or "mol. %" refer to a weight, volume, or molar percentage of a component, respectively, based on the total weight, the total volume, or the total moles of material that includes the component. In a non-limiting example, <NUM> moles of component in <NUM> moles of the material is <NUM> mol. % of component.

The terms "inhibiting" or "reducing" or "preventing" or "avoiding" or any variation of these terms, when used in the claims and/or the specification, includes any measurable decrease or complete inhibition to achieve a desired result.

The term "lubricating oil," as that term is used in the specification and/or claims, means a class of oils used to reduce the friction, heat, and wear between mechanical components that are in contact with each other. The term "used lubricating oil," as that term is used in the specification and/or claims, means lubricating oil that has partially or completely lost its capability of reducing the friction, heat, and wear between mechanical components after a period of usage; and/or lubricating oil that has accumulated contaminants after a period of usage.

The term "primarily," as that term is used in the specification and/or claims, means greater than any of <NUM> wt. %, <NUM> mol. %, and <NUM> vol. For example, "primarily" may include <NUM> wt. % to <NUM> wt. % and all values and ranges there between, <NUM> mol. % to <NUM> mol. % and all values and ranges there between, or <NUM> vol. % to <NUM> vol. % and all values and ranges there between.

Other objects, features and advantages of the present invention will become apparent from the following figures, detailed description, and examples. It should be understood, however, that the figures, detailed description, and examples, while indicating specific embodiments of the invention, are given by way of illustration only and are not meant to be limiting.

Currently, high-value petro-chemicals including one or more olefins and/or BTX are produced via steam cracking and/or catalytically cracking of naphtha or other fractions of petroleum. However, as the demands for these chemicals consistently increase, feedstock shortage has become a long term concern. Another method used for producing light olefins is catalytic dehydrogenation of paraffins. However, the catalytic dehydrogenation process requires a separate production system, thereby increasing the capital expenditure for producing light olefins. Furthermore, the catalytic dehydrogenation process requires the feedstock to be a single alkane, resulting in high costs for feedstocks. The present invention provides a solution to at least some of these problems. The solution is premised on a method of producing one or more olefins using plastic derived oil and/or used lubricating oil as feedstocks. This method is capable of providing an alternative source of feedstocks to the feedstocks for the conventional methods, thereby addressing the concerns about insufficient feedstocks. Notably, the feedstocks for the discovered method are derived from waste or recyclable sources, resulting in a more environmentally friendly process compared to the conventional methods. Moreover, this method can be implemented in the existing system for steam cracking and/or catalytic cracking, resulting in reduced capital expenditure compared to catalytic dehydrogenation of paraffins. These and other non-limiting aspects of the present invention are discussed in further detail in the following sections.

Methods of producing high-value chemicals, including one or more olefins, have been discovered. Embodiments of the method are capable of relieving the concerns about shortage of feedstocks for light olefins production. Furthermore, embodiments of the method are capable of reducing capital expenditure and production costs for light olefins and/or BTX production compared to catalytic dehydrogenation of paraffins. As shown in <FIG>, embodiments of the invention include method <NUM> for producing one or more light olefins. Method <NUM> may be implemented by system <NUM>, as shown in <FIG>.

According to the invention, as shown in block <NUM>, method <NUM> includes pyrolyzing, in pyrolysis unit <NUM>, plastic material of mixed plastic waste stream <NUM> to form plastic derived oil of plastic derived oil stream <NUM>. In embodiments of the invention, pyrolyzing at block <NUM> is performed at a temperature in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. In embodiments of the invention, pyrolyzing at block <NUM> is performed at a pressure in a range of <NUM> to <NUM> barg and all ranges and values there between including ranges of <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> bar, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, and <NUM> to <NUM> barg. In embodiments of the invention, the plastic derived oil includes paraffinic, naphthenic, and aromatic hydrocarbons, or combinations thereof.

According to the invention, as shown in block <NUM>, method <NUM> includes blending, in blender <NUM>, plastic derived oil of plastic derived oil stream <NUM> with used lubricating oil of lubricating oil stream <NUM> to form blended hydrocarbon feed stream <NUM>. In embodiments of the invention, blending is performed at a temperature in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>.

In embodiments of the invention, as shown in block <NUM>, method <NUM> may include dewatering blended hydrocarbon feed stream <NUM> to produce dewatered blended feed stream <NUM>. In embodiments of the invention, dewatered blended feed stream <NUM> includes less than <NUM> wt.

According to the invention, as shown in block <NUM>, method <NUM> includes separating, in separation unit <NUM>, blended hydrocarbon feed stream <NUM> (and/or dewatered blended feed stream <NUM>) to form (<NUM>) light-end stream <NUM> comprising primarily C<NUM> to C<NUM> hydrocarbons and (<NUM>) heavy hydrocarbon feed stream <NUM>. In embodiments of the invention, heavy hydrocarbon feed stream <NUM> comprises primarily C<NUM> to C<NUM> hydrocarbons. In embodiments of the invention, separation unit <NUM> can include a distillation column and the distillation column is operated at an overhead temperature range of <NUM> to <NUM> and a reboiler range of <NUM> to <NUM>. The distillation column of separation unit <NUM> may be operated at an operating pressure of <NUM> to <NUM> bar and all ranges and values there between including ranges of <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, and <NUM> to <NUM> bar. According to the invention, as shown in block <NUM>, method <NUM> includes flowing light-end stream <NUM> to steam cracking unit <NUM>.

According to the invention, as shown in block <NUM>, method <NUM> includes processing heavy hydrocarbon feed stream <NUM> to produce steam cracking feedstock stream <NUM>. In embodiments of the invention, steam cracking feedstock stream <NUM> includes primarily paraffinic and naphthenic hydrocarbons. In the method of the invention, as shown in block <NUM>, processing at block <NUM> comprises distilling heavy hydrocarbon feed stream <NUM> via vacuum distillation to produce vacuum distillation residue stream <NUM> and vacuum distilled hydrocarbon stream <NUM>. In embodiments of the invention, the vacuum distillation at block <NUM> is performed at an overhead temperature of <NUM> to <NUM> and a reboiler range of <NUM> to <NUM>. A feed temperature for vacuum distillation at block <NUM> is in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. The vacuum distillation at block <NUM> may be performed at an operating pressure of <NUM> to <NUM> mbar (abs). In embodiments of the invention, vacuum distillation residue stream <NUM> comprises primarily hydrocarbons with a boiling point higher than <NUM>.

In the method of the invention, as shown in block <NUM>, processing at block <NUM> comprises processing vacuum distilled hydrocarbon stream <NUM> via extraction to produce poly-aromatic stream <NUM> comprising primarily poly-aromatics and intermediate stream <NUM>. In the method of the invention, the extraction at block <NUM> includes liquid-liquid extraction. The extraction at block <NUM> is performed at a temperature in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. In embodiments of the invention, intermediate stream <NUM> comprises less than <NUM> wt. % poly-aromatics.

In the method of the invention, as shown in block <NUM>, processing at block <NUM> comprises hydroprocessing intermediate stream <NUM> to produce steam cracking feedstock stream <NUM>. In embodiments of the invention, hydroprocessing at block <NUM> is performed in presence of a catalyst comprising cobalt, nickel, molybdenum, zeolite, acidic catalyst, or combinations thereof. In embodiments of the invention, hydroprocessing at block <NUM> is performed at an operating pressure of <NUM> to <NUM> barg and all ranges and values there between including ranges of <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, <NUM> to <NUM> barg, and <NUM> to <NUM> barg. In embodiments of the invention, hydroprocessing at block <NUM> is performed at a temperature in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. In embodiments of the invention, hydroprocessing at block <NUM> is performed at a weight hourly space velocity in a range of <NUM> to <NUM> hr-<NUM> and all ranges and values there between including ranges of <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, and <NUM> to <NUM> hr-<NUM>. In embodiments of the invention, hydroprocessing at block <NUM> is configured to saturate unsaturated hydrocarbon molecules, remove hetero-atoms such as, but not limited to, sulfur, oxygen, nitrogen, and chlorine, and/or crack the feed hydrocarbon stream into a product hydrocarbon stream with a lower boiling range.

According to embodiments of the invention, as shown in block <NUM>, method <NUM> may include hydroprocessing light-end stream <NUM> under reaction conditions sufficient to produce a hydroprocessed light-end stream (not shown in <FIG>). In embodiments of the invention, hydroprocessing of light-end stream <NUM> at block <NUM> is performed in the presence of a catalyst comprising cobalt, nickel, molybdenum, or combinations thereof. Hydroprocessing conditions at block <NUM> may be less severe than hydroprocessing conditions for hydroprocessing intermediate stream <NUM> at block <NUM>. In embodiments of the invention, hydroprocessing conditions at block <NUM> include a temperature in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. Hydroprocessing conditions at block <NUM> may include a pressure in a range of <NUM> to <NUM> bar and all ranges and values there between including ranges of <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, and <NUM> to <NUM> bar. In embodiments of the invention, hydroprocessing conditions at block <NUM> include a weight hourly space velocity in a range of <NUM> to <NUM> hr-<NUM> and all ranges and values there between including ranges of <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, <NUM> to <NUM> hr-<NUM>, and <NUM> to <NUM> hr-<NUM>.

According to the invention, as shown in block <NUM>, method <NUM> includes cracking (<NUM>) hydrocarbons of steam cracking feedstock stream <NUM> and (<NUM>) hydrocarbons of light-end stream (and/or the hydroprocessed light-end stream) to produce one or more olefins. In embodiments of the invention, cracking at block <NUM> is performed in a steam cracking unit. The cracking at block <NUM> may be performed at a temperature in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. Cracking at block <NUM> may be performed with a residence time of steam-cracking furnace in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. In embodiments of the invention, cracking at block <NUM> is performed with a hydrocarbon feed to steam volumetric ratio in a range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. In embodiments of the invention, the one or more olefins produced at block <NUM> includes one or more of ethylene, propylene, butenes, butadiene, or combinations thereof. In embodiments of the invention, cracking at block <NUM> further produces BTX (benzene, toluene, xylene). According to embodiments of the invention, as shown in block <NUM>, method <NUM> may include pyrolyzing, in pyrolysis unit <NUM>, at least some hydrocarbons of (i) vacuum distillation residue stream <NUM> and/or (ii) hydrocarbons of poly-aromatic stream <NUM> to produce additional plastic derived oil. In embodiments of the invention, a portion of (i) vacuum distillation residue stream <NUM> and/or (ii) hydrocarbons of poly-aromatic stream <NUM> may go to disposal.

Claim 1:
A method of producing one or more olefins, the method comprising:
pyrolizing, in a pyrolysis unit, plastic material to form a plastic derived oil; blending the plastic derived oil with a used lubricating oil to form a blended hydrocarbon feed;
separating the blended hydrocarbon feed to form (<NUM>) a light-end stream comprising primarily C<NUM> to C<NUM> hydrocarbons and (<NUM>) a heavy hydrocarbon feed;
flowing the light-end stream to a steam cracking unit;
processing the heavy hydrocarbon feed to produce a steam cracking feedstock; and
cracking (<NUM>) hydrocarbons of the steam cracking feedstock and (<NUM>) hydrocarbons of the light-end stream to produce one or more olefins;
wherein the processing of the heavy hydrocarbon feed comprises:
distilling the heavy hydrocarbon feed via vacuum distillation to produce a vacuum distillation residue and a vacuum distilled hydrocarbon stream;
processing the vacuum distilled hydrocarbon stream via liquid-liquid extraction to produce a poly-aromatics stream comprising primarily poly-aromatics and an intermediate stream comprising paraffinic, aromatic, and naphthenic hydrocarbons; and
hydroprocessing the intermediate stream to produce the steam cracking feedstock; wherein a used lubricating oil is lubricating oil that has partially or completely lost its capability of reducing the friction, heat, and wear between mechanical components after a period of usage, and/or lubricating oil that has accumulated contaminants after a period of usage.