Patent Application
20220275283
This disclosure relates to processes and systems for upgrading a hydrocarbon-containing feed. In particular, this disclosure relates to processes and systems for converting a hydrocarbon-containing feed by pyrolysis to produce various products, e.g., olefins and fuel oil products.
Steam cracking, also referred to as pyrolysis, has long been used to crack various hydrocarbon-containing feeds into olefins, preferably light olefins such as ethylene, propylene, and butenes. Conventional steam cracking utilizes a pyrolysis furnace (“steam cracker”) that has two main sections: a convection section and a radiant section. The hydrocarbon-containing feed typically enters the convection section of the furnace as a liquid (except for light feedstocks that typically enter as a vapor) where the feedstock is typically heated and vaporized by indirect heat exchange with a hot flue gas from the radiant section and by direct contact with steam. The vaporized feedstock and steam mixture is fed into the radiant section where the cracking takes place. The resulting pyrolysis effluent, including olefins, leaves the pyrolysis furnace for further downstream processing, including quenching.
Conventional pyrolysis furnaces do not have the flexibility to process residues, crudes, or many residues, crude gas oils, or naphthas that are contaminated with non-volatile components. Non-volatile components, if present in the feed, typically cause fouling within the radiant section of the pyrolysis furnace. An external vaporization drum or flash drum has been implemented to separate vaporized hydrocarbons from liquid hydrocarbons to address the fouling problems in the pyrolysis furnace. The vaporized hydrocarbons are then cracked in the pyrolysis furnace and the liquid hydrocarbons that include nonvolatile components are removed and used as fuel. The liquid hydrocarbons, however, still contain a substantial quantity of hydrocarbons which, if converted into higher-value lighter hydrocarbons such as olefins via cracking, would bring substantial additional value to the crude oil feed. Thus, for decades the petrochemical industry has been trying to take advantage of relatively low-cost heavy crude oil to make substantial quantities of valuable chemicals such as olefins. The large amount of non-volatiles in the low-cost heavy crude oil, however, requires extensive and expensive processing.
There is a need, therefore, for improved processes and systems for upgrading hydrocarbon-containing feeds, e.g., petroleum feeds that include a resid, to produce valuable chemical products such as olefins.
This disclosure satisfies this and other needs.
The present inventors have devised a process and system for converting a hydrocarbon-containing feed by pyrolysis. In some examples, the process for converting a hydrocarbon-containing feed by pyrolysis can include (I) feeding the hydrocarbon-containing feed into a pyrolysis reaction zone and (II) feeding a plurality of fluidized particles having a first temperature into the pyrolysis reaction zone. The first temperature can be sufficiently high to enable pyrolysis of at least a portion of the hydrocarbon-containing feed on contacting the particles. The particles can include an oxide of a transition metal element capable of oxidizing molecular hydrogen (H2) at the first temperature. The process can also include (III) contacting at least a portion of the hydrocarbon-containing feed with the particles in the pyrolysis reaction zone to effect pyrolysis of at least a portion of the hydrocarbon-containing feed to produce a pyrolysis effluent that can include olefins, hydrogen, and the particles. At least a portion of the transition metal element in the particles in the pyrolysis effluent can be at a reduced state compared to the transition metal element in the particles fed into the pyrolysis reaction zone.
In other examples, the process for converting a hydrocarbon-containing feed by pyrolysis, can include (I) feeding the hydrocarbon-containing feed to a pyrolysis reaction zone and (II) feeding a plurality of fluidized particles having a first temperature into the pyrolysis reaction zone. The hydrocarbon-containing feed can include a first transition metal element. The first temperature can be sufficiently high to enable pyrolysis of at least a portion of the hydrocarbon-containing feed on contacting the particles. The particles can include an oxide of a second transition metal element capable of oxidizing molecular hydrogen (H2) at the first temperature. The process can also include (III) contacting at least a portion of the hydrocarbon-containing feed with the particles in the pyrolysis reaction zone to effect pyrolysis of at least a portion of the hydrocarbon-containing feed to produce a pyrolysis effluent that can include olefins, hydrogen, and the particles. At least a portion of the second transition metal element in the particles in the pyrolysis effluent can be at a reduced state compared to the transition metal element in the particles fed into the pyrolysis reaction zone. At least a portion of the first transition metal element in the hydrocarbon-containing feed can deposit onto the particles. The process can also include (IV) optionally steam stripping the pyrolysis effluent using a stripping steam stream, (V) obtaining from the pyrolysis effluent optionally admixed with the stripping steam stream a first hydrocarbon stream rich in hydrocarbons and a first particle stream rich in the particles, (VI) oxidizing and heating at least a portion of the particles in the first particle stream in a combustion zone such that at least a portion of the second transition metal element in the particles oxidizes to a higher oxidation state compared to the second transition metal element in the particles in the pyrolysis effluent, and (VII) feeding at least a portion of the heated and oxidized particles to the pyrolysis reaction zone as at least a portion of the plurality of fluidized particles fed into the pyrolysis reaction zone in step (II).
In some examples, the system for converting a hydrocarbon-containing feed by pyrolysis can include (i) a pyrolysis reactor adapted for receiving the hydrocarbon-containing feed and a fluidized stream of particles having a first temperature, allowing at least a portion of the hydrocarbon-containing feed to contact the particles to effect pyrolysis of at least a portion of the hydrocarbon-containing feed, and discharging a pyrolysis effluent. The first temperature can be sufficiently high to enable pyrolysis of at least a portion of the hydrocarbon-containing feed. The particles can include an oxide of a transition metal capable of oxidizing molecular hydrogen (H2) at the first temperature. The system can also include (ii) a first separation vessel adapted for receiving the pyrolysis effluent, optionally receiving a stripping steam stream, separating the pyrolysis effluent to obtain a first hydrocarbon stream rich in hydrocarbons and a first particle stream rich in the particles, discharging the first hydrocarbon stream, and discharging the first particle stream. The system can also include (iii) a combustion vessel adapted for receiving a stream of an oxidizing agent, receiving at least a portion of the first particle stream, optionally receiving a fuel stream, optionally combusting the fuel, combusting the particles, heating the particles, oxidizing the particles, and discharging a combustion zone effluent that can include the heated and oxidized particles and a flue gas. The system can also include (iv) a second separation vessel adapted for receiving the combustion zone effluent, separating the combustion zone effluent to obtain a second particle stream rich in the particles and a first flue gas stream rich in the flue gas, discharging the second particle stream, and discharging the first flue gas stream. The system can also include (v) a channel adapted for feeding at least a portion of the second particle stream to the pyrolysis reactor. The system can also include (vi) a quenching section adapted for receiving the first hydrocarbon stream, receiving a stream of a quenching medium, and discharging a quenched mixture stream that can include the quenching medium and the first hydrocarbon stream. The system can also include (vii) a third separation vessel that can include a cyclone. The third separation vessel can be adapted for receiving the quenched mixture stream, separating the quenched mixture stream to obtain a third particle stream rich in the particles and a second hydrocarbon stream rich in hydrocarbons, discharging the third particle stream, and discharging the second hydrocarbon stream. The system can also include (viii) a channel adapted for feeding at least a portion of the third particle stream to the first separation vessel or to the combustion vessel.
The FIGURE depicts an illustrative system for converting a hydrocarbon-containing feed by pyrolysis, according to one or more embodiments described.
Various specific embodiments, versions and examples of the invention will now be described, including preferred embodiments and definitions that are adopted herein for purposes of understanding the claimed invention. While the following detailed description gives specific preferred embodiments, those skilled in the art will appreciate that these embodiments are exemplary only, and that the invention may be practiced in other ways. For purposes of determining infringement, the scope of the invention will refer to any one or more of the appended claims, including their equivalents, and elements or limitations that are equivalent to those that are recited. Any reference to the “invention” may refer to one or more, but not necessarily all, of the inventions defined by the claims.
In this disclosure, a process is described as comprising at least one “step.” It should be understood that each step is an action or operation that may be carried out once or multiple times in the process, in a continuous or discontinuous fashion. Unless specified to the contrary or the context clearly indicates otherwise, multiple steps in a process may be conducted sequentially in the order as they are listed, with or without overlapping with one or more other steps, or in any other order, as the case may be. In addition, one or more or even all steps may be conducted simultaneously with regard to the same or different batch of material. For example, in a continuous process, while a first step in a process is being conducted with respect to a raw material just fed into the beginning of the process, a second step may be carried out simultaneously with respect to an intermediate material resulting from treating the raw materials fed into the process at an earlier time in the first step. Preferably, the steps are conducted in the order described.
Unless otherwise indicated, all numbers indicating quantities in this disclosure are to be understood as being modified by the term “about” in all instances. It should also be understood that the precise numerical values used in the specification and claims constitute specific embodiments. Efforts have been made to ensure the accuracy of the data in the examples. However, it should be understood that any measured data inherently contains a certain level of error due to the limitation of the technique and/or equipment used for making the measurement.
Certain embodiments and features are described herein using a set of numerical upper limits and a set of numerical lower limits. It should be appreciated that ranges including the combination of any two values, e.g., the combination of any lower value with any upper value, the combination of any two lower values, and/or the combination of any two upper values are contemplated unless otherwise indicated.
As used herein, the indefinite article “a” or “an” shall mean “at least one” unless specified to the contrary or the context clearly indicates otherwise. Thus, embodiments using “a pyrolysis reactor” include embodiments where one, two or more pyrolysis reactors are used, unless specified to the contrary or the context clearly indicates that only one pyrolysis reactor is used.
The term “crude” as used herein means whole crude oil as it flows from a wellhead, a production field facility, a transportation facility, or other initial field processing facility, optionally including crude that has been processed by a step of desalting, treating, and/or other steps as may be necessary to render it acceptable for conventional distillation in a refinery. Crude, as used herein, is presumed to contain resid. The term “crude fraction”, as used herein, means a hydrocarbon fraction obtained via the fractionation of crude.
The term “resid” as used herein refers to a bottoms cut of a crude distillation process that contains non-volatile components. Resids are complex mixtures of heavy petroleum compounds otherwise known in the art as residuum or residual. Atmospheric resid is the bottoms product produced from atmospheric distillation of crude where a typical endpoint of the heaviest distilled product is nominally 343° C., and is referred to as 343° C. resid. The term “nominally”, as used herein, means that reasonable experts may disagree on the exact cut point for these terms, but by no more than +/−55.6° C. preferably no more than +/−27.8° C. Vacuum resid is the bottoms product from a distillation column operated under vacuum where the heaviest distilled product can be nominally 566° C., and is referred to as 566° C. resid.
The term “non-volatile components” as used herein refers to the fraction of a hydrocarbon-containing feed, e.g., a petroleum feed, having a nominal boiling point of at least 590° C., as measured by ASTM D6352-15 or D-2887-18. Non-volatile components include coke precursors, which are large, condensable molecules that condense in the vapor and then form coke during pyrolysis of the hydrocarbon-containing feed.
The term “hydrocarbon” as used herein means (i) any compound consisting of hydrogen and carbon atoms or (ii) any mixture of two or more such compounds in (i). The term “Cn hydrocarbon,” where n is a positive integer, means (i) any hydrocarbon compound comprising carbon atom(s) in its molecule at the total number of n, or (ii) any mixture of two or more such hydrocarbon compounds in (i). Thus, a C2 hydrocarbon can be ethane, ethylene, acetylene, or mixtures of at least two of these compounds at any proportion. A “Cm to Cn hydrocarbon” or “Cm-Cn hydrocarbon,” where m and n are positive integers and m<n, means any of Cm, Cm+1, Cm+2, . . . , Cn−1, Cn hydrocarbons, or any mixtures of two or more thereof. Thus, a “C2 to C3 hydrocarbon” or “C2-C3 hydrocarbon” can be any of ethane, ethylene, acetylene, propane, propene, propyne, propadiene, cyclopropane, and any mixtures of two or more thereof at any proportion between and among the components. A “saturated C2-C3 hydrocarbon” can be ethane, propane, cyclopropane, or any mixture thereof of two or more thereof at any proportion. A “Cn+ hydrocarbon” means (i) any hydrocarbon compound comprising carbon atom(s) in its molecule at the total number of at least n, or (ii) any mixture of two or more such hydrocarbon compounds in (i). A “Cn− hydrocarbon” means (i) any hydrocarbon compound comprising carbon atoms in its molecule at the total number of at most n, or (ii) any mixture of two or more such hydrocarbon compounds in (i). A “Cm hydrocarbon stream” means a hydrocarbon stream consisting essentially of Cm hydrocarbon(s). A “Cm-Cn hydrocarbon stream” means a hydrocarbon stream consisting essentially of Cm-Cn hydrocarbon(s).
The term “olefin product” as used herein means a product that includes an olefin, preferably a product consisting essentially of an olefin. An olefin product in the meaning of this disclosure can be, e.g., an ethylene stream, a propylene stream, a butylene stream, an ethylene/propylene mixture stream, and the like.
The term “consisting essentially of” as used herein means the composition, feed, effluent, product, or other stream comprises a given component at a concentration of at least 60 wt %, preferably at least 70 wt %, more preferably at least 80 wt %, more preferably at least 90 wt %, still more preferably at least 95 wt %, based on the total weight of the composition, feed, effluent, product, or other stream in question.
The term “aromatic” as used herein is to be understood in accordance with its art-recognized scope which includes alkyl substituted and unsubstituted mono- and polynuclear compounds.
The term “rich” when used in phrases such as “X-rich” or “rich in X” means, with respect to an outgoing stream obtained from a device, that the stream comprises material X at a concentration higher than in the feed material fed to the same device from which the stream is derived.
The term “lean” when used in phrases such as “X-lean” or “lean in X” means, with respect to an outgoing stream obtained from a device, that the stream comprises material X at a concentration lower than in the feed material fed to the same device from which the stream is derived.
The terms “channel” and “line” are used interchangeably and mean any conduit configured or adapted for feeding, flowing, and/or discharging a gas, a liquid, and/or a fluidized solids feed into the conduit, through the conduit, and/or out of the conduit, respectively. For example, a composition can be fed into the conduit, flow through the conduit, and/or discharge from the conduit to move the composition from a first location to a second location. Suitable conduits can be or can include, but are not limited to, pipes, hoses, ducts, tubes, and the like.
As used herein, “wt %” means percentage by weight, “vol %” means percentage by volume, “mol %” means percentage by mole, “ppm” means parts per million, and “ppm wt” and “wppm” are used interchangeably to mean parts per million on a weight basis. All concentrations herein are expressed on the basis of the total amount of the composition in question, unless specified otherwise. Thus, the concentrations of the various components of the “hydrocarbon-containing feed” are expressed based on the total weight of the hydrocarbon-containing feed. All ranges expressed herein should include both end points as two specific embodiments unless specified or indicated to the contrary.
Nomenclature of elements and groups thereof used herein are pursuant to the Periodic Table used by the International Union of Pure and Applied Chemistry after 1988. An example of the Periodic Table is shown in the inner page of the front cover of Advanced Inorganic Chemistry, 6th Edition, by F. Albert Cotton et al. (John Wiley & Sons, Inc., 1999).
A typical crude includes a mixture of hydrocarbons with varying carbon numbers and boiling points. Thus, by using conventional atmospheric distillation and vacuum distillation, one can produce a range of fuel products with varying boiling points: naphtha, gasoline, kerosene, distillate, and tar. It is highly desired, however, to convert the large hydrocarbon molecules contained in the crude into more valuable, lighter products including but not limited to ethylene, propylene, butylenes, and the like, which can be further made into more valuable products such as polyethylene, polypropylene, ethylene-propylene copolymers, butyl rubbers, and the like.
The hydrocarbon-containing feed can be, can include, or can be derived from petroleum, plastic, natural gas condensate, landfill gas (LFG), biogas, coal, biomass, biobased oils, rubber, or any mixture thereof. In some examples, the hydrocarbon-containing feed can include a non-volatile component. In some examples, the petroleum can be or can include any crude or any mixture thereof, any crude fraction or any mixture thereof, or any mixture of any crude with any crude fraction. In some examples, the petroleum can be or can include: atmospheric resid, vacuum resid, steam cracked gas oil and residue, gas oil, heating oil, hydrocrackate, atmospheric pipestill bottoms, vacuum pipestill streams including bottoms, gas oil condensate, heavy non-virgin hydrocarbon stream from refineries, vacuum gas oil, heavy gas oil, naphtha contaminated with crude, heavy residue, C4's/residue admixture, naphtha/residue admixture, hydrocarbon gases/residue admixture, hydrogen/residue admixture, gas oil/residue admixture, or any mixture thereof. Non-limiting examples of crudes can be or can include, but are not limited to: Tapis, Murban, Arab Light, Arab Medium, and/or Arab Heavy as examples.
In some examples, the plastic can be or can include polyethylene terephthalate (PETE or PET), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polystyrene (PS), polycarbonate (PC), polylactic acid (PLA), acrylic (PMMA), acetal (polyoxymethylene, POM), acrylonitrile-butadiene-styrene (ABS), fiberglass, nylon (polyamides, PA), polyester (PES) rayon, polyoxybenzylmethylenglycolanhydride (bakelite), polyurethane (PU), polyepoxide (epoxy), or any mixture thereof. The rubber can be or can include natural rubber, synthetic rubber, or a mixture thereof. In some examples, the biomass can be or can include, but is not limited to, wood, agricultural residues such as straw, stover, cane trash, and green agricultural wastes, agro-industrial wastes such as sugarcane bagasse and rice husk, animal wastes such as cow manure and poultry litter, industrial waste such as black liquor from paper manufacturing, sewage, municipal solid waste, food processing waste, or any mixture thereof. In some examples, the biogas can be produced via anaerobic digestion, e.g., the biogas produced during the anaerobic digestion of sewage. In some examples, the biobased oil can be or can include oils that can degrade biologically over time. In some examples, the biobased oil can be degraded via processes of bacterial decomposition and/or by the enzymatic biodegradation of other living organisms such as yeast, protozoans, and/or fungi. Biobased oils can be derived from vegetable oils, e.g., rapeseed oil, castor oil, palm oil, soybean oil, sunflower oil, corn oil, hemp oil, or chemically synthesized esters.
If the hydrocarbon-containing feed includes material that is solid at room temperature (solid material), e.g., plastic, biomass, coal, and/or rubber, the solid material can be reduced to any desired particle size via well-known processes. For example, if the hydrocarbon-containing feed includes solid material, the solid material can be ground, crushed, pulverized, other otherwise reduced into particles that have any desired average particle size. In some examples, the solid matter can be reduced to an average particle size that can be submicron or from about 1 μm, about 10 μm or about 50 μm to about 100 μm, about 150 μm, or about 200 μm. For example, the average particle size of the hydrocarbon feedstock, if solid matter, can range from about 75 μm to about 475 μm, from about 125 μm to about 425 μm, or about 175 μm to about 375 μm.
In some examples, one or more vapor-liquid separators, e.g., a vaporization drum or a flashing drum, can be used to separate a hydrocarbon-containing feed, e.g., a raw crude oil or a desalted crude oil, to obtain an overhead vapor effluent and a bottoms liquid effluent. The bottoms liquid effluent can have a cutoff point from 300° C. to 700° C., e.g., 310° C. to 550° C., as measured according to ASTM D1160-18. The hydrocarbon-containing feed can be or can be obtained from the bottoms liquid effluent. In this example, at least a portion of the overhead vapor effluent can optionally be fed into another processing unit, e.g., a radiant section of a steam cracker furnace, a fluid catalytic cracker, other systems capable of upgrading the overhead vapor effluent, or any combination thereof. Suitable vaporization drums or flashing drums can include those disclosed in U.S. Pat. Nos. 7,674,366; 7,718,049; 7,993,435; 8,105,479; and 9,777,227. In some examples, if an overhead vapor and a liquid bottoms is separated from a hydrocarbon feed, the overhead vapor can be steam cracked according to the processes and systems disclosed in U.S. Pat. Nos. 6,419,885; 7,993,435; 9,637,694; and 9,777,227; U.S. Patent Application Publication No. 2018/0170832; and International Patent Application Publication No. WO 2018/111574.
The processes for converting the hydrocarbon-containing feed, e.g., a crude oil or a fraction thereof, by pyrolysis disclosed herein can produce a pyrolysis effluent that can include, but is not limited to, olefins, e.g., ethylene, propylene, and/or one or more butenes, aromatics, e.g., benzene, toluene, and/or xylene, molecular hydrogen (H2), or any mixture thereof. In some examples, the hydrocarbon-containing feed can be introduced, supplied, or otherwise fed into a pyrolysis reaction zone. In some examples, the hydrocarbon-containing feed can be heated, e.g., via indirect heat exchange with a heated medium, to a temperature in a range from 100° C., 150° C., or 200° C. to 300° C., 350° C., or 400° C., e.g., 250° C. to 300° C., prior to feeding the hydrocarbon-containing feed into the pyrolysis reaction zone.
A plurality of fluidized particles can also be introduced, supplied, or otherwise fed into the pyrolysis reaction zone. The plurality of fluidized particles can have a first temperature when fed into the pyrolysis reaction zone. The first temperature can be sufficiently high to enable pyrolysis of at least a portion of the hydrocarbon-containing feed or fraction thereof on contacting the particles within the pyrolysis reaction zone. The plurality of fluidized particles can include an oxide of a transition metal element capable of oxidizing molecular hydrogen (H2) at the first temperature.
The hydrocarbon-containing feed can contact the plurality of fluidized particles in the pyrolysis reaction zone to effect pyrolysis of at least a portion of the hydrocarbon-containing feed to produce the pyrolysis effluent that can include olefins, hydrogen, and the particles. In some examples, the pyrolysis effluent can be at a second temperature that can be lower than the first temperature. At least a portion of the transition metal element disposed on and/or in the particles in the pyrolysis effluent can be at a reduced state as compared to the transition metal element in the plurality of fluidized particles fed into the pyrolysis reaction zone.
The first temperature can be 750° C., 800° C., 850° C., 900° C., or 950° C. to 1,050° C., 1,100° C., 1,200° C., 1,300° C., 1,400° C., or 1,500° C. In some examples, the first temperature can be at least 800° C., at least 820° C., at least 840° C., at least 850° C., at least 875° C., at least 900° C., at least 950° C., or at least 975° C. to 1,000° C., 1,050° C., 1,100° C., 1,200° C., 1,300° C., or 1,400° C.
The hydrocarbon-containing feed can be contacted with an amount of the plurality of fluidized particles within the pyrolysis reaction zone sufficient to effect a desired level or degree of pyrolysis of the hydrocarbon-containing feed. In some examples, a weight ratio of the plurality of fluidized particles to the hydrocarbon-containing feed when contacted within the pyrolysis reaction zone can be 5:1, 10:1, 12:1, 15:1, or 20:1 to 25:1, 30:1, 35:1, 40:1, 45:1, 50:1, 55:1, or 60:1.
The pyrolysis reaction zone can be located in any suitable reactor or other process environment capable of operating under the pyrolysis process conditions. In some examples, the pyrolysis reaction zone can be located in short contact time fluid bed. In some examples, the pyrolysis reaction zone can be located in a downflow reactor, an upflow reactor, a counter-current flow reactor, or vortex reactor. In a preferred example, the pyrolysis reaction zone can be located in a downflow reactor.
In some examples, the hydrocarbon-containing feed can be contacted with the plurality of fluidized particles in the pyrolysis reaction zone in the presence of steam. The steam, if present, can be introduced or otherwise fed into the pyrolysis reaction zone in an amount sufficient to provide a weight ratio of the steam to the hydrocarbon-containing feed of 0.05:1, 0.1:1, 0.2:1, 0.25:1, 0.3:1, or 0.4:1 to 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, or 1:1. For example, the weight ratio of the steam to the hydrocarbon-containing feed can be about 0.2:1 to about 0.6:1 or about 0.3:1 to about 0.5:1.
The hydrocarbon-containing feed can contact the plurality of fluidized particles within the pyrolysis reaction zone under a vacuum, at atmospheric pressure, or at a pressure greater than atmospheric pressure. In some examples, the hydrocarbon-containing feed can contact the plurality of fluidized particles within the pyrolysis reaction zone under an absolute pressure of 101 kPa, 150 kPa, 200 kPa, 250 kPa, 300 kPa, or 400 kPa to 450 kPa, 500 kPa, 550 kPa, 600 kPa, 650 kPa, 700 kPa, 750 kPa, 800 kPa, or 840 kPa. In some examples, the hydrocarbon-containing feed can contact the plurality of fluidized particles within the pyrolysis reaction zone under an absolute pressure of 101 kPa to 800 kPa, 101 kPa to 700 kPa, 101 kPa to 500 kPa, 200 kPa to 800 kPa, 220 kPa to 460 kPa, or 101 kPa to 450 kPa. In other examples, the hydrocarbon-containing feed can contact the plurality of fluidized particles within the pyrolysis reaction zone under an absolute pressure of less than 800 kPa, less than 700 kPa, less than 600 kPa, less than 500 kPa, less than 450 kPa, less than 400 kPa, less than 350 kPa, less than 300 kPa, less than 250 kPa, less than 200 kPa, or less than 150 kPa.
The hydrocarbon-containing feed can contact the plurality of fluidized particles within the pyrolysis reaction zone for a residence time of 1 millisecond (ms), 5 ms, 10 ms, 25 ms, 50 ms, 75 ms, or 100 ms to 300 ms, 500 ms, 750 ms, 1,000 ms, 1,250 ms, 1,500 ms, 1,750 ms, or 2,000 ms. In some examples, the hydrocarbon-containing feed can contact the plurality of fluidized particles within the pyrolysis reaction zone for a residence time of 10 ms to 500 ms, 10 ms to 100 ms, 20 ms to 200 ms, 30 ms to 225 ms, 50 ms to 250 ms, 125 ms to 500 ms, 200 ms to 600 ms, or 20 ms to 140 ms. In other examples, the hydrocarbon-containing feed can contact the plurality of fluidized particles within the pyrolysis reaction zone for a residence time of less than 1,000 ms, less than 800 ms, less than 600 ms, less than 400 ms, less than 300 ms, less than 200 ms, less than 150 ms, or less than 100 ms.
Without wishing to be bound by theory, it is believed that the particles that include the oxide of the transition metal element capable of oxidizing molecular hydrogen at the first temperature can do so via one or more processes or mechanisms. Regardless of the overall mechanism, the oxidized transition metal element can facilitate the conversion of molecular hydrogen to water and in doing so the oxidation state of the oxide of the transition metal element can be reduced. For example, if the transition metal element is vanadium, the oxide of vanadium on the fluidized particles fed into the pyrolysis reaction zone can be at an oxidation state of +5 (for example) and at least a portion of the oxide of vanadium on the fluidized particles in the pyrolysis effluent can be at an oxidation state of +4, +3, or +2. Without wishing to be bound by theory, it is also believed that one or more of the oxides of one or more transition metal elements may be capable of being reduced from an oxidized state all the way to the metallic state.
Additionally, the oxide of the transition metal element can favor the conversion, e.g., oxidation and/or combustion, of hydrogen over the oxidation and/or combustion of hydrocarbons, e.g., olefins, in the pyrolysis reaction zone. In some examples, the oxide of the transition metal element can favor the conversion of hydrogen over the conversion of hydrocarbons at a rate of 2:1, 3:1, 4:1, 5:1, 6:1, or 7:1 to 8:1, 9:1, 10:1, or 11:1.
In some examples, the presence of the oxide of the transition metal in the fluidized particles, e.g., disposed on an outer surface of the particles and/or at least partially within the particles, can reduce an amount of molecular hydrogen present in the pyrolysis effluent as compared to a comparative pyrolysis effluent produced under the same process conditions and with the same fluidized particles except the oxide of the transition metal is absent. In some examples, the amount of molecular hydrogen (H2) in the pyrolysis effluent in the pyrolysis effluent as compared to a comparative pyrolysis effluent can be reduced by 0.001%, 0.01%, or 0.05% to 0.07%, 0.08%, 0.09%, 0.1%, 0.15%, or 0.2% as compared to the comparative pyrolysis effluent. In other examples, the amount of molecular hydrogen (H2) in the pyrolysis effluent in the pyrolysis effluent as compared to a comparative pyrolysis effluent can reduced by at least 0.001%, at least 0.01%, at least 0.05%, or at least 0.07% as compared to the comparative pyrolysis effluent. In some examples, the amount of molecular hydrogen present in the pyrolysis effluent can be less than 3 wt %, less than 2.5 wt %, less than 2 wt %, less than 1.5 wt %, less than 1.4, less than 1.3 wt %, less than 1.2 wt %, less than 1.1 wt %, less than 1 wt %, less than 0.9 wt %, less than 0.8 wt %, less than 0.7 wt %, less than 0.6 wt %, less than 0.5 wt %, or less than 0.4 wt %. In some examples, the amount of molecular hydrogen present in the pyrolysis effluent can be 0.01 wt % to 2.5 wt %, 0.5 wt % to 2 wt %, or 1 wt % to 1.7 wt %.
In some examples, during contact of the hydrocarbon-containing feed with the plurality of fluidized particles in the pyrolysis reaction zone, coke can be formed on the surface of the particles. For example, when the hydrocarbon-containing feed includes non-volatile components at least a portion of the non-volatile components can deposit, condense, adhere, or otherwise become disposed on the surface of the particles and/or at least partially within the particles, e.g., within pores of the particles, in the form of coke. As such, the pyrolysis effluent can include the plurality of particles in which at least a portion of the transition metal element can be at a reduced state and at least a portion of the particles can include coke formed or otherwise disposed on the surface thereof and/or at least partially therein. In some examples, the particles in the pyrolysis effluent can include 1 wt %, 3 wt %, 5 wt %, 7 wt %, 10 wt %, or 15 wt % to 20 wt %, 25 wt %, 30 wt %, 35 wt %, 40 wt %, 45 wt %, or 50 wt % of coke, based on a total weight of the particles.
The plurality of fluidized particles can be or include a core and at least one transition metal element and/or at least one oxidized transition metal element disposed on and/or in the core. In some examples, the core can be inert, i.e., inert during pyrolysis of the hydrocarbon-containing feed. The core can be or can include, but is not limited to, silica, alumina, titania, zirconia, magnesia, pumice, ash, clay, diatomaceous earth, bauxite, spent fluidized catalytic cracker catalyst, or any mixture or combination thereof. Preferred support materials can be or can include Al2O3, ZrO2, SiO2, and combinations thereof, more preferably, SiO2, Al2O3, or SiO2/Al2O3.
In some examples, the transition metal element and/or the oxide thereof can be disposed on and/or within, e.g., within pores, of the core. In some examples, the transition metal element and/or the oxide thereof can form a surface layer on the core. The surface layer on the core can be continues or discontinuous.
The core and/or the particles that include the at least one transition metal element and/or at least one oxidized transition metal element disposed on and/or in the core can have an average size in a range from 10 micrometers (μm), 15 μm, 25 μm, 50 μm, or 75 μm to 150 μm, 200 μm, 300 μm, 400 μm. The core and/or the particles that include the at least one transition metal element and/or at least one oxidized transition metal element disposed on and/or in the core can have a surface area in a range from 10 m2/g, 50 m2/g, or 100 m2/g to 200 m2/g, 500 m2/g, or 700 m2/g.
In some examples, the fluidized particles can be, can include, or can otherwise be derived from spent fluid catalytic converter (“FCC”) catalyst. As such, a significant and highly advantageous use for spent FCC catalyst has been discovered because the processes disclosed herein can significantly extend the useful life of FCC catalyst in upgrading hydrocarbons long after the FCC catalyst is considered to be spent and no longer useful in the fluid catalytic cracking process.
The plurality of fluidized particles can include any oxide of a transition metal element capable of converting at least a portion of any hydrogen to water, e.g., via oxidation, combustion, or other mechanism, within the pyrolysis reaction zone. In some examples, the transition metal element can be or can include, but is not limited to, titanium, vanadium, chromium, manganese, iron, cobalt, niobium, nickel, molybdenum, tantalum, tungsten, alloys thereof, and mixtures thereof. In some examples, the transition metal element can be or can include vanadium, nickel, an alloy thereof, or a mixture thereof.
The amount of transition metal element disposed on and/or at least partially within the plurality of fluidized particles can be in a range from 500 wppm, 750 wppm, 1,000 wppm, 2,500 wppm, 5,000 wppm, or 1 wt % to 2 wt %, 5 wt %, 10 wt %, 15 wt %, 20 wt %, 30 wt %, 40 wt %, or 50 wt %, based on a total weight of the particles. In some examples, the amount of transition metal element disposed on and/or at least partially within the plurality of fluidized particles can be at least 1 wt %, at least 2.5 wt %, at least 3 wt %, at least 3.5 wt %, at least 4 wt %, at least 4.5 wt %, at least 5 wt %, or at least 10 wt % up to 15 wt %, 20 wt %, 30 wt %, 40 wt %, or 50 wt %.
It has been surprisingly and unexpectedly discovered that the process conditions within the pyrolysis reaction zone can be sufficient to cause at least a portion of any transition metal in the hydrocarbon-containing feed to deposit, condense, adhere, or otherwise become disposed on the surface of the particles and/or at least partially within the particles. During contact of the hydrocarbon-containing feed with the plurality of particles within the pyrolysis reaction zone, additional transition metal element can become disposed on the plurality of particles. The additional transition metal element can be the same or different than the transition metal element already disposed on the plurality of particles. As such, the particles fed into the pyrolysis reaction zone can include an oxide of a first transition metal disposed on and/or in the particles and the particles discharged from the pyrolysis reaction zone as a component of the pyrolysis effluent can include the oxide of the first transition metal element and a second transition metal element and/or an oxide of the second transition metal element disposed on and/or in the particles. At least a portion of the oxide of the first transition metal element in the pyrolysis effluent can be in a reduced state relative to the oxide of a first transition metal disposed on and/or in the particles when fed into the pyrolysis reaction zone.
In some examples, the first transition metal element can be or can include, but is not limited to, titanium, vanadium, chromium, manganese, iron, cobalt, niobium, nickel, molybdenum, tantalum, tungsten, alloys thereof, and mixtures thereof and the second transition metal element can be or can include, but is not limited to, titanium, vanadium, chromium, manganese, iron, cobalt, niobium, nickel, molybdenum, tantalum, tungsten, alloys thereof, and mixtures thereof. In some examples, the first transition metal element and the second transition metal element can be the same. In other examples, the first transition metal element and the second transition metal element can be different.
In some examples, the fluidized particles can be or can include inert cores without any transition metal element or oxide thereof disposed on and/or in the inert cores. In other examples, the fluidized particles can be or can include the inert cores with an undesirably low amount of transition metal element or oxide thereof disposed on and/or in the inert cores. These inert cores free of or containing less than the desired amount of transition metal element or oxide thereof disposed on and/or in the inert cores can be referred to as “starter particles”. In some examples, at least a portion of the starter particles can be derived from a fluid catalytic converter catalyst.
A plurality of the starter particles and a source material for the transition metal element can be fed into the pyrolysis reaction zone. The starter particles can be contacted with the source material for the transition metal element in the pyrolysis reaction zone to obtain a contacting mixture effluent that can include the starter particles having a layer of the source material for the transition metal element deposited thereon. At least a portion of the starter particles having the layer of the source material for the transition metal element can be heated and oxidized in the combustion zone to form the particles that can include the oxide of the transition metal element. The source material for the transition metal element can be or can include, but is not limited to, the hydrocarbon-containing feed, a feed containing the desired transition metal(s) and a carrier fluid, e.g., fine particles of the transition metal element and/or fine particles of an oxide of the transition metal element and a hydrocarbon as the carrier fluid. In some examples, the amount of transition metal element and/or oxide thereof that can be deposited on and/or in the starter particles to form the particles that can include the transition metal element and/or the oxide of the transition metal element in an amount of 1 wt %, 2 wt %, 3 wt %, 4 wt %, 5 wt %, or 6 wt % to 10 wt %, 12 wt %, 14 wt %, 18 wt %, 20 wt %, or 25 wt %.
In some examples, the particles can be fabricated from a transition metal element-containing material, e.g., a physical mixture of a transition metal oxide and a binder such as clay, which can result in the distribution of the transition metal element throughout the particles. In other examples, the particles can be fabricated from transition metal element-free support particles, followed by impregnation of the support particles with a transition metal compound solution, followed by drying and calcination, which can result in the distribution of the transition metal element throughout the particles if the support particles are porous or a distribution of the transition metal element in a surface layer if the support particles are non-porous. In other examples, as discussed above, transition metal element-free support particles can be charged into the pyrolysis zone and contacted with a transition metal element-containing in the hydrocarbon-containing feed or a feed containing the desired transition metal element(s) and a carrier fluid to form transition metal element-containing particles in situ, which can result in the distribution of the transition metal element throughout the particles if the support particles are porous or a distribution or the transition metal element in a surface layer if the support particles are non-porous.
A first hydrocarbon stream rich in hydrocarbons and a first particle stream rich in the particles can be recovered or otherwise obtained from the pyrolysis effluent. For example, the pyrolysis effluent can be fed from the pyrolysis reaction zone into a first separation vessel configured or adapted to receive the pyrolysis effluent and separate the first hydrocarbon stream rich in hydrocarbons and the first particle stream rich in particles from the pyrolysis effluent. The first separation vessel can be configured or adapted to discharge the first hydrocarbon stream and the first particle stream therefrom.
In some examples, at least a portion of the particles in the pyrolysis effluent can optionally be stripped by contacting the particles in the pyrolysis effluent with a first stripping medium within the first separation vessel. For example, the pyrolysis effluent can be fed from the pyrolysis reaction zone into the first separation vessel, which can be configured or adapted to contact the pyrolysis effluent or at least at portion of the particles in the pyrolysis effluent with a first stripping medium, e.g., a steam stream, and separate the pyrolysis effluent to obtain the first hydrocarbon stream rich in hydrocarbons and rich in the optional first stripping medium and the first particle stream rich in particles. As such, in some examples the first separation vessel can also be referred to a stripping vessel. In some examples, a residence time of the particles in the pyrolysis effluent separated within the first separation vessel from the pyrolysis effluent can be in a range from 30 seconds, 1 minute, 3 minutes, 5 minutes, or 10 minutes to 15 minutes, 17 minutes, 20 minutes, or 25 minutes before being discharged therefrom as the first particle stream rich in particles.
In some examples, the first separation vessel can include an inertial separator configured to separate a majority of the particles from the hydrocarbons to produce the first hydrocarbon stream rich in hydrocarbons and the first particle stream rich in the particles. Inertial separators can be configured or adapted to concentrate or collect the particles by changing a direction of motion of the pyrolysis effluent such that the particle trajectories cross over the hydrocarbon gas streamlines and the particles are either concentrated into a small part of the gas flow or are separated by impingement onto a surface. In some examples, a suitable inertial separator can include a cyclone. The pyrolysis effluent, when introduced into a cyclone can undergo a vortex motion so that the hydrocarbon gas acceleration is centripetal and the particles, therefore, move centrifugally towards the outside of the cyclone, i.e., an inner surface of the cyclone. Illustrative cyclones can include, but are not limited to, those disclosed in U.S. Pat. Nos. 7,090,081; 7,309,383; and 9,358,516.
In some examples, the optional first stripping medium, e.g., steam, can fed into the first separation vessel. In some examples, the optional first stripping medium can fed into the first separation vessel at a weight ratio of the first stripping medium to the pyrolysis effluent fed into the first separation vessel in a range from 1:1,000, 2:1,000, or 2.5:1,000, or 3:1,000 to 4:1,000, 6:1,000, 8:1,000, or 10:1,000.
In some examples, a residence time within the separation vessel of the hydrocarbons in the pyrolysis effluent separated from the pyrolysis effluent can be less than 1,000 ms, less than 750 ms, less than 500 ms, less than 250 ms, less than 100 ms, less than 75 ms, less than 50 ms, or less than 25 ms. In some examples, a residence time within the separation vessel of the hydrocarbons in the pyrolysis effluent separated from the pyrolysis effluent can be in a range from 2 ms, 4 ms, 6 ms, or 8 ms to 10 ms, 12 ms, 14 ms, 16 ms, 18 ms, or 20 ms before being discharged therefrom as the first hydrocarbon stream. In some examples, the residence time within the separation vessel of the hydrocarbons in the pyrolysis effluent separated within from the pyrolysis effluent can be less than 20 ms, less than 15 ms, less than 10 ms, less than 7 ms, less than 5 ms, or less than 3 ms before being discharged therefrom as the first hydrocarbon stream. The first hydrocarbon stream rich in hydrocarbons, upon being discharged from the first separation vessel, can be free or substantially free of any particles. In some examples, the first hydrocarbon stream discharged from the first separation vessel can include less than 25 wt %, less than 20 wt %, less than 15 wt %, less than 12 wt %, less than 10 wt %, less than 8 wt %, less than 6 wt %, less than 5 wt %, less than 3 wt %, or less than 1 wt % of the particles present in the pyrolysis effluent.
In some examples, a residence time of the hydrocarbons in the first hydrocarbon stream separated from the pyrolysis effluent spanning from the initial introduction of the hydrocarbon-containing feed and fluidized particles into the pyrolysis zone to the recovery of the first hydrocarbon stream rich in hydrocarbons from the first separation vessel can be 5 ms, 10 ms, 25 ms, 50 ms, 75 ms, or 100 ms to 300 ms, 500 ms, 750 ms, 1,000 ms, 1,250 ms, 1,500 ms, 1,750 ms, or 2,000 ms. In other examples, residence time of the hydrocarbons in the first hydrocarbon stream separated from the pyrolysis effluent spanning from the initial introduction of the hydrocarbon-containing feed and fluidized particles into the pyrolysis zone to the recovery of the first hydrocarbon stream rich in hydrocarbons from the first separation vessel can be less than 1,500 ms, less than 1,250 ms, less than 1,000 ms, less than 800 ms, less than 600 ms, less than 400 ms, less than 300 ms, less than 200 ms, less than 150 ms, or less than 100 ms.
The first hydrocarbon stream rich in hydrocarbons and optionally the first stripping medium can be at a temperature in a range from 800° C., 850° C., or 900° C. to 950° C., 1,000° C., 1,100° C., or 1,200° C. upon discharge from the first separation vessel. As such, it can be desirable that the first hydrocarbon stream be cooled as quickly as possible after discharging from the first separation vessel, to a sufficiently low temperature in a very short period of time reduce or minimize reactive species from recombining to form larger molecules and/or such that the olefins do not become saturated to form alkanes during the cooling process. The first hydrocarbon stream can be cooled to a temperature of less than 750° C., less than 700° C., less than 650° C., less than 600° C., less than 550° C., less than 500° C., less than 450° C., or less than 400° C. In some examples, the first hydrocarbon stream can be cooled to a temperature of in a range from 250° C., 300° C., 350° C., 400° C., 450° C., or 500° C. to less than 700° C., less than 675° C., less than 650° C., less than 625° C., less than 600° C., less than 550° C., or less than 500° C. In some examples, the first hydrocarbon stream can be cooled from the temperature upon discharge from the first separation vessel to the temperature of the cooled first hydrocarbon stream in a range from 1 ms, 3 ms, 5 ms, or 7 ms to 10 ms, 12 ms, 15 ms, or 20 ms. In other examples, the first hydrocarbon stream can be cooled from the temperature upon discharge from the first separation vessel to the temperature of the cooled first hydrocarbon stream in less than 20 ms, less than 15 ms, less than 10 ms, less than 7 ms, less than 5 ms, less than 4 ms, less than 3 ms, less than 2 ms, or less than 1 ms.
In some examples, a preferred process for cooling the first hydrocarbon stream can include indirectly exchanging heat from the first hydrocarbon stream to a quenching medium, e.g., water (liquid or gaseous), quenching oil, or other fluid to produce a cooled first hydrocarbon stream. Suitable heat exchangers can be or can include, but are not limited to, shell-and-tube heat exchanger, a plate and frame heat exchanger, brazed aluminum heat exchangers, a plate and fin heat exchanger, a spiral wound heat exchanger, a coil wound heat exchanger, a U-tube heat exchanger, a bayonet style heat exchanger, any other apparatus, or any combination thereof.
In other examples, a preferred process for cooling the first hydrocarbon stream can include injecting a quenching medium, e.g., a quenching oil, into the first hydrocarbon stream in a quenching section downstream, e.g., a transfer line exchanger (“TLE”), of the first separation vessel to produce the cooled first hydrocarbon stream. In another example, the first hydrocarbon stream can be cooled by indirectly exchanging heat and by contacting with a quenching medium. In some examples, the first hydrocarbon stream can have a temperature in a range from 800° C., 850° C., or 900° C. to 950° C., 1,000° C., 1,100° C., or 1,200° C. when initially contacted with the quenching medium or when heat is initially transferred from the first hydrocarbon stream to a heat transfer medium in a heat exchanger.
Any suitable quenching medium(s) having a temperature and/or heat capacity capable of reducing the temperature of the first hydrocarbon stream to a desirable level via direct contact and/or indirect contact can be used. In some examples, the quenching medium can be or can include, but is not limited to, water, a quench oil, a gas oil, naphtha, a stream rich in paraffins, or the like. In some examples, the quench medium can be or can include a recycled quench oil, a recycled gas oil, a recycled naphtha, a recycle stream rich in paraffins, or the like separated from the first hydrocarbon stream in a downstream separation process.
In a preferred embodiment, the quenching medium can be or can include a stream of quenching oil separated from the first hydrocarbon stream in a downstream distillation column. In a more preferred embodiment, at least a portion of a stream rich in paraffins separated from the first hydrocarbon stream in a downstream separation system, e.g., a recovery sub-system, can be injected into the first hydrocarbon stream in the quenching section to combine with the first hydrocarbon stream to form a mixture having a temperature substantially lower than the first hydrocarbon stream upon being discharged from the first separation vessel.
It has been discovered that the first hydrocarbon stream upon being discharged from the first separation vessel can be at a temperature sufficient to effect pyrolysis of at least a portion of the hydrocarbons in the quench medium. As such, by utilizing a quenching medium that includes paraffins, the amount of olefins in the cooled or quenched first hydrocarbon steam can be increased relative to the first hydrocarbon stream upon being discharged from the first separation reactor.
In some examples, the first hydrocarbon stream can be contacted with a quench medium that includes one or more paraffins, e.g., ethane, propane, butane, pentane, hexane, or a mixture thereof. Such quench medium can be referred to as a stream rich in paraffins. By quenching the first hydrocarbon stream with a quench medium that includes one or more paraffins the amount of C4-olefins in the quenched first hydrocarbon stream can be increased relative to the amount of C4-olefins in the first hydrocarbon stream recovered from the first separation vessel because at least a portion of the paraffins can be cracked to produce additional olefins.
The time from contacting at least a portion of the hydrocarbon-containing feed with the particles in the pyrolysis reaction zone to indirectly exchanging heat to a quenching medium and/or contacting the first hydrocarbon stream with a quenching medium can be in a range from 10 ms, 25 ms, 50 ms, 75 ms, or 100 ms to 300 ms, 500 ms, 750 ms, 1,000 ms, 1,250 ms, 1,500 ms, 1,750 ms, or 2,000 ms. In some examples, the time from contacting at least a portion of the hydrocarbon-containing feed with the particles in the pyrolysis reaction zone to indirectly exchanging heat to the quenching medium and/or contacting the first hydrocarbon stream with the quenching medium can be less than 2,000 ms, less than 1,500 ms, less than 1,000 ms, less than 800 ms, less than 600 ms, less than 400 ms, less than 200 ms, less than 150 ms, less than 100 ms, less than 75 ms, or less than 50 ms.
The cooled first hydrocarbon stream can include, but is not limited to, one or more of the following: hydrogen, methane, ethane, ethylene, propane, propylene, butenes, naphtha, gas oil, a heavy oil, and tar. The naphtha, gas oil, heavy oil, and tar each include a mixture of compounds, primarily a mixture of hydrocarbon compounds. It should be understood that typically there is an overlap between naphtha and gas oil, an overlap between gas oil and heavy oil or quench oil, and an overlap between heavy oil and tar in composition and boiling point range. Naphtha, also referred to as pygas, is a complex mixture of C5+ hydrocarbons, e.g., C5-C10+ hydrocarbons, having an initial atmospheric boiling point of 25° C. to 50° C. and a final boiling point of 220° C. to 265° C., as measured according to ASTM D2887-18. In some examples, naphtha can have an initial atmospheric boiling point of 33° C. to 43° C. and a final atmospheric boiling point of 234° C. to 244° C., as measured according to ASTM D2887-18. The final atmospheric boiling point of the gas oil is typically 275° C. to 285° C., as measured according to ASTM D2887-18. The final atmospheric boiling point of the heavy oil or quency oil is typically 455° C. to 475° C., as measured according to ASTM D2887-18. In some examples, the tar product can have an initial boiling point of at least 200° C. and/or a final atmospheric boiling point of >600° C., as measured according to ASTM D2887-18.
The cooled first hydrocarbon stream can be separated to obtain a second hydrocarbon stream rich in hydrocarbons and a third particle stream rich in the particles. In some examples, separating the cooled first hydrocarbon stream can include using a cyclone. For example, the cooled first hydrocarbon stream can be fed into a third separation vessel configured or adapted to receive the cooled first hydrocarbon stream and separate the second hydrocarbon stream rich in hydrocarbons and the third particle stream rich in particles therefrom. The third separation vessel can be configured or adapted to discharge the second hydrocarbon stream and the third particle stream therefrom.
In some examples, the particles in the cooled first hydrocarbon stream can optionally be stripped by contacting at least a portion of the particles in the cooled first hydrocarbon stream with a third stripping medium within the third separation vessel. For example, the cooled first hydrocarbon stream can be fed into the third separation vessel, which can be configured or adapted to contact at least a portion of the particles in the cooled first hydrocarbon stream with the third stripping medium, e.g., a steam stream, to obtain the second hydrocarbon stream rich in hydrocarbons and rich in the optional third stripping medium and the third particle stream rich in the particles. As such, in some examples, the third separation vessel can also be referred to as a stripping vessel or as including a stripping zone or stripping vessel. In some examples, the third separation vessel can be or can include one or more multi-cyclone (multi-clone) separators. In some examples, the third separation vessel can include the conventional separators are available from several vendors, such as the Polutrol, Shell and Emtrol, such as the Polutrol TSS and the Emtrol Cytrol TSS.
The second hydrocarbon stream rich in hydrocarbons can include less than 1 wt %, less than 0.7 wt %, less than 0.5 wt %, less than 0.3 wt %, or less than 0.1 wt % of any particles. In some examples, at least a portion of the third particle stream can rich in the particles can be introduced into the first separation vessel, e.g., a stripping zone within the first separation vessel. In other examples, at least a portion of the third particle stream rich in particles can be recycled to the combustion zone. In some examples, at least a portion of the third particle stream can be removed from the process. In some examples, a first portion of the third particle stream can be introduced into the first separation vessel and/or recycled to the combustion zone and a second portion of the third particle stream can be removed from the process.
The second hydrocarbon stream rich in hydrocarbons can be further cooled, e.g., indirect heat exchange with a heat transfer medium, quenching with a quench medium, e.g., a portion of the heavy oil or other stream(s) separated from the second hydrocarbon stream via one or more downstream separation processes, water, or the like.
The second hydrocarbon stream or the further cooled second hydrocarbon stream can be separated to obtain two or more products therefrom. In some examples, the second hydrocarbon stream can be separated within a fractionation zone to obtain a bottoms heavy stream, a gas oil stream, and an overhead stream rich in naphtha and light hydrocarbons. The overhead stream can be further separated to obtain a naphtha stream, at least one olefin stream rich in one or more olefins, and at least one hydrogen stream rich in hydrogen. In some examples, the overhead stream can also be separated to obtain the stream rich in paraffins, which, as discussed above, can be used as at least a portion of the quench medium contacted with the first hydrocarbon stream to produce the quenched first hydrocarbon stream.
In some examples, at least a portion of the gas oil stream can be used as the quenching medium that can contact the first hydrocarbon stream rich in hydrocarbons to produce the quenched first hydrocarbon stream. In some examples, a first portion of the gas oil stream can be used as the quenching medium and a second portion can be removed from the process.
In some examples, the bottoms heavy stream can be cooled in one or more heat exchanges by indirectly exchanging heat to a heat transfer medium, e.g., boiler feed water, to produce a cooled bottoms heavy stream and a pre-heated boiler feed water. The preheated boiler feed water can be used to cool the second hydrocarbon stream rich in hydrocarbons by indirectly exchanging heat.
In some examples, a portion or first portion of the cooled bottoms heavy stream can be contacted with the second hydrocarbon steam rich in hydrocarbons or the cooled second hydrocarbon stream rich in hydrocarbons as a quench medium. In some examples a portion or second portion of the cooled bottoms heavy stream can be fed into the combustion zone as the fuel or as at least a portion of the fuel that can optionally be fed thereto.
Returning to the first particle stream rich in particles, at least a portion of the particles in the first particle stream can be fed into the combustion zone. The first particle stream can be oxidized and heated under conditions sufficient such that at least a portion of the transition metal element in the particles can be oxidized to a higher oxidation state as compared to the transition metal element in and/or at least partially within the particles in the pyrolysis effluent to produce a combustion zone effluent. An oxidant or oxidizing agent and optionally a fuel can be fed into the combustion zone in addition to the first particle stream rich in particles. In some examples, the oxidizing agent can be or can include molecular oxygen. In some examples, the oxidizing agent can be or can include air, oxygen enriched air, oxygen depleted air, or any mixture thereof. The fuel can be or can include any combustible source of material capable of combusting in the presence of the oxidizing agent within the pyrolysis reaction zone. Suitable fuels can be or can include, but are not limited to, naphtha, gas oil, fuel oil, quench oil, fuel gas, molecular hydrogen, or any mixture thereof. In some examples, the fuel can be or can include a bottoms heavy oil stream separated from the first hydrocarbon stream. The combustion zone effluent, which can include heated and oxidized particles and a flue gas, can be obtained from the combustion zone.
The first particle stream rich in particles fed into the combustion zone can be oxidized and heated at a temperature in a range from 800° C., 900° C., or 1,000° C. to 1,100° C., 1,200° C., or 1,300° C. In some examples, an amount of the optional fuel that can be introduced into the combustion zone can be sufficient to provide additional heat within the combustion zone to produce the combustion zone effluent that includes the heated and oxidized particles at the desired temperature.
In some examples, when the first particle stream rich in particles includes coke disposed on and/or at least partially in the particles, at least a portion of the coke can be combusted within the combustion zone. The heated and oxidized particles in the combustion zone effluent obtained from the combustion zone can include less coke as compared to the particles in the first particle stream rich in particles or can be free of any coke. In some examples, the particles in the combustion zone effluent can include less than 5 wt %, less than 4 wt %, less than 3 wt %, less than 2 wt %, less than 1 wt %, less than 0.5 wt %, or less than 0.1 wt % of coke.
Without wishing to be bound by theory, it is believed that for a transition metal element that has multiple valences, the transition metal element when at a high oxidative state may be less selective toward oxidation of molecular hydrogen as compared to the transition metal element when at a lower oxidative state. As such, in some examples, an amount of oxidant or oxidizing agent fed into the combustion zone can be controlled or otherwise adjusted to produce the combustion zone effluent that includes the transition metal element at a desired or predetermined oxidized state. As such, in some examples, the combustion zone can be operated under complete combustion conditions that can produce a combustion zone effluent that includes a flue gas that can contain at least a portion of the oxidizing agent fed into the combustion zone, e.g., 0.5 mol % to 2.5 mol % or 1 mol % to 2 mol % of the oxidizing agent, and a low concentration of carbon monoxide, e.g., less than 1 mol % of carbon dioxide. In other examples, the combustion zone can be operated under partial combustion conditions that can produce a combustion zone effluent that includes a flue gas that can contain at least 1 mol % of carbon monoxide and less than 0.5 mol %, e.g., 0 mol %, of the oxidizing agent. The flue gas produced during partial combustion can be free or substantially free of any of the oxidizing agent introduced into the combustion zone. Accordingly, the combustion zone can be operated under conditions sufficient to cause at least a portion of the transition metal element in the particles to be oxidized to a higher oxidation state as compared to the transition metal element in the particles in the pyrolysis effluent, but not necessarily oxidized to the highest oxidation state possible for a given transition metal element.
At least a portion of the oxidized and heated particles in the combustion zone effluent can be supplied to the pyrolysis reaction zone as at least a portion of the plurality of fluidized particles fed to the pyrolysis reaction zone. In some example, the combustion zone effluent can under go one or more optional treatments before feeding at least a portion of the oxidized and heated particles to the pyrolysis reaction zone.
The combustion zone effluent can optionally be separated into a second particle stream that can be rich in the heated and oxidized particles and a first flue gas stream that can be rich in flue gas. For example, the combustion zone effluent can be discharged from the combustion zone into a second separation vessel configured or adapted to receive the combustion zone effluent and separate the second particle stream and the flue gas therefrom. The second separation vessel can be configured or adapted to discharge the second particle stream and the first flue gas therefrom. The second particle stream can be recycled or otherwise fed into the pyrolysis reaction zone as at least a portion of the particles fed into the pyrolysis reaction zone.
In some examples, the combustion zone effluent can optionally be stripped by contacting the combustion zone effluent within the second separation vessel with a second stripping medium. For example, the combustion effluent can be fed from the combustion zone into the second separation vessel, which can be configured or adapted to contact the combustion zone effluent with a second stripping medium, e.g., a steam stream, and separate the combustion zone effluent to obtain the second particle stream rich in particles and the first flue gas stream rich in the optional second stripping medium stream. As such, the second separation vessel can also be referred to a stripping vessel.
The first flue gas stream can be at a temperature in a range of 800° C., 900° C., or 1,000° C., to 1,100° C., 1,200° C., or 1,300° C. In some examples, the first flue gas stream can be quenched by contacting the first flue gas stream with a quenching medium to produce a quenched first flue gas stream. In some examples, the quenching medium contacted with the first flue gas stream can be or can include, but is not limited to, air, water (liquid or gaseous), or a mixture thereof.
The first flue gas stream or the quenched first flue gas stream can be separated to obtain a second flue gas stream rich in flue gas and a fourth particle stream rich in particles. In some examples, separating the first flue gas stream or the quenched first flue gas stream can include using a cyclone. For example, the first flue gas stream or the quenched first flue gas stream can be fed into a fourth separation vessel configured or adapted to receive the first flue gas stream or the quenched first flue gas stream and separate the second flue gas stream and the fourth particle stream therefrom. The fourth separation vessel can be configured or adapted to discharge the second flue gas stream and the fourth particle stream.
In some examples, at least a portion of the particle sin the first flue gas stream or the quenched first flue gas stream can optionally be stripped by contacting at least a portion of the particles with a fourth stripping medium within the fourth separation vessel. For example, the first flue gas stream or the quenched first flue gas stream can be fed into the fourth separation vessel, which can be configured or adapted to contact at least a portion of the particles with the fourth stripping medium, e.g., a steam stream, to obtain the second flue gas stream rich in flue gas and rich in the optional fourth stripping medium and the fourth particle stream rich in particles. As such, the fourth separation vessel can also be referred to a stripping vessel.
If the first flue gas stream is quenched, the first flue gas stream can be at a temperature sufficiently low, e.g., 875° C. or less, to enable the third separation vessel to be constructed of low-temperature metallurgy. In some examples, the fourth separation vessel can be or can include one or more multi-cyclone (multi-clone) separators. In some examples, the fourth separation vessel can include the conventional separators are available from several vendors, such as the Polutrol, Shell and Emtrol, such as the Polutrol TSS and the Emtrol Cytrol TSS.
The second flue gas stream can be used to indirectly heat one or more process streams. In some examples, the second flue gas stream can be used to indirectly heat the oxidant or oxidizing agent prior to feeding the oxidizing agent into the combustion zone. The second flue gas stream can also be used to indirectly heat the hydrocarbon-containing feed prior to feeding the hydrocarbon-containing feed into the pyrolysis reaction zone. The second flue gas stream can also be used to indirectly heat boiler feed water to produce steam. The steam can be used as stripping steam, a motive fluid, e.g., to fluidize the particles fed to the pyrolysis reaction zone and/or to fluidize the first particle stream rich in particles, as the optional steam that can be fed into the pyrolysis reaction zone, or any other use that could utilize the steam.
The second flue gas stream can be used to indirectly heat any two or more process streams in a serial flow arrangement. For example, the second flue gas stream can be used to indirectly heat the oxidizing agent and produce a first cooled second flue gas, the first cooled second flue gas can be used to indirectly heat the hydrocarbon-containing feed and produce a second cooled second flue gas, and the second cooled second flue gas can be used to indirectly heat the boiler feed water to produce steam and a third cooled second flue gas. In another example, a first portion of the second flu gas can be used to heat the oxidizing agent, a second portion of the second flue gas can be used to heat the hydrocarbon-containing feed, and a third portion of the second flue gas can be used to heat the boiler feed water. The second flue gas or the cooled second flue gas can be further treated if needed to remove any sulfur oxide or other contaminants prior to venting the atmosphere or otherwise disposing of.
In some examples, at least a portion of the fourth particle stream rich in particles can be recycled to the combustion zone. In some examples, at least a portion of the fourth particle stream can be removed from the process. In some examples, a first portion of the fourth particle stream can be recycled to the combustion zone and a second portion of the fourth particle stream can be removed from the process.
It has also been discovered that as the amount of transition metal or oxide thereof increases the effectiveness of the particles to facilitate the oxidation and/or combustion of hydrogen can begin to decrease. As such, it can be desirable to remove a portion of the particles from the process when an amount of the transition metal element and/or the oxide thereof increases above a predetermined level. The predetermined amount of the transition metal element and/or the oxide thereof can be in a range from 10 wt %, 12 wt %, or 14 wt % to 16 wt %, 18 wt %, 20 wt %, 22 wt %, or 25 wt %, based on the weight of the particles. In some examples, the particles can be removed from the process at a rate of about 0.1 wt %, about 0.3 wt %, about 0.5 wt %, about 0.7 wt %, or about 1 wt % to about 1.3 wt %, about 1.5 wt %, about 1.7 wt %, about 2 wt %, about 3 wt %, about 5 wt %, about 10 wt % or more per 24 hours, based on the total weight of particles being circulated through the process. In some examples, the particles can be removed from the process at a continuous rate or in batches and replace particles can be introduced into the process at a continuous rate or in batches.
In some examples, a portion of the particles can be removed or obtained from the first particle stream rich in particles, the second particle stream rich in particles, the third particle stream rich in particles, or the fourth particle stream rich in particles. When a portion of the particles is removed from the process replacement particles can be added into the process. For example, the replacement particles can be fed into the combustion zone and/or mixed, blended, or otherwise combined with the hydrocarbon-containing feed and/or any other stream that includes particles such as the first particle stream rich in particles the second particle stream rich in particles, the third particle stream rich in particles, and/or the fourth particle stream rich in particles.
This disclosure is further illustrated by the following non-limiting example.
The FIGURE depicts an illustrative system 100 for processing a hydrocarbon-containing feed in line 102, according to one or more embodiments. The system 100 can include, but is not limited to, one or more pyrolysis reactors, e.g., a downflow reactor, 115, one or more first separation vessels 120, one or more combustion vessels 125, one or more second separation vessels 130, and one or more channels 132 configured or adapted to feed a particle stream from second separation vessel 130 to the pyrolysis reactor 115.
In some examples, the first separation vessel 120 can include one or more inertial separators 119 that can be configured to separate a majority of the particles from the gaseous hydrocarbons to provide a first hydrocarbon stream rich in hydrocarbons via line 121 and the particles can fall or otherwise flow toward an end or lower portion of the first separation vessel 120. In some examples, a suitable inertial separator can include a cyclone. The pyrolysis effluent, when introduced into a cyclone can undergo a vortex motion so that the hydrocarbon gas acceleration is centripetal and the particles, therefore, move centrifugally towards the outside of the cyclone, i.e., an inner surface of the cyclone. Illustrative cyclones can include, but are not limited to, those disclosed in U.S. Pat. Nos. 7,090,081; 7,309,383; and 9,358,516.
In some examples, the system 100 can also include one or more first quenching stages or quenching sections 135, one or more third separation vessels 140, and one or more channels two are shown 143, 144 configured or adapted to feed at least a portion of a particle stream from the third separation vessel to the first separation vessel 120 (shown) and/or the combustion vessel 125 (not shown). In some examples, the system 100 can also include one or more heat exchangers 150 and one or more distillation columns 160. In some examples, the system 100 can also include one or more channels 162 and/or 173 configured or adapted to feed a side-draw product and/or an overhead product to the quenching zone 135. In some examples, the system 100 can also include one or more channels (two are shown) 161,166 configured or adapted to feed at least a portion of a bottoms product from the distillation column 160 to the combustor 125. In some examples, the system 100 can also include one or more recovery sub-systems 170. In some examples, the system 100 can also include one or more fourth separation vessels 185 and one or more channels 187 configured or adapted to feed at least a portion of a particle stream from the fourth separation vessel 185 to the combustion vessel 125. In some examples, the system 100 can also include one or more heat exchangers 106 and one or more channels 108 configured or adapted to transfer a flue gas stream from the fourth separation vessel 185 to the heat exchanger 106.
In some examples, an oxidant or an oxidizing agent, e.g., air, via line 101, the hydrocarbon-containing feed via line 102, and water, e.g., boiler feed water, via line 103 can be fed into one or more first heat exchange stages, e.g., a first heat exchanger, 105, one or more second heat exchange stages, e.g., a second heat exchanger, 106, and one or more third heat exchange stages, e.g., a third heat exchanger, 107, respectively. A heat source or heated medium, e.g., a combustion or flue gas, via line 108 can be serially fed into the first heat exchange stage 105, the second heat exchange stage 106, and the third heat exchange stage 107, respectively, thereby transferring heat to the oxidant, the hydrocarbon-containing feed, and the boiler feed water, respectively. A heated oxidizing agent via line 110 and a heated hydrocarbon-containing feed via line 111 can be obtained from the first and second heat exchange stages 105, and 106, respectively. Steam via line 112 and a cooled medium, e.g., water, via line 113 can be obtained from the third heat exchange stage 107.
At least a portion of the hydrocarbon-containing feed via line 111 and a fluidized stream of particles via line 132 can be fed into the pyrolysis reactor 115. The fluidized stream of particles, upon introduction into the pyrolysis reactor 115, can have a first temperature. The hydrocarbon-containing feed can contact the particles within the pyrolysis reactor 115 to effect pyrolysis of at least a portion of the hydrocarbon-containing feed. The first temperature can be sufficiently high to enable the pyrolysis of at least a portion of the hydrocarbon-containing feed. As discussed above, the particles can include an oxide of a transition metal element that can be capable of oxidizing molecular hydrogen (H2) at the first temperature. In some examples, at least a portion of the steam via line 112 can optionally be fed into the pyrolysis reactor 115.
During pyrolysis of the hydrocarbon-containing feed coke can deposit, condense, adhere, or otherwise become disposed on the surface of the particles and/or at least partially within the particles. It has been discovered that when the hydrocarbon-containing feed in line 111 includes one or more transition metal elements, which can be the same or different than the transition metal element already on the particles when fed into the pyrolysis reactor 115, at least a portion of the transition metal element in the hydrocarbon-containing feed can also deposit, condense, adhere, or otherwise become disposed on the surface of the particles and/or at least partially within the particles.
A pyrolysis effluent via outlet 116 can be discharged from the pyrolysis reactor 115 into the first separation vessel 120 configured or adapted to receive and separate the pyrolysis effluent to obtain a first hydrocarbon stream rich in hydrocarbons and a first particle stream rich in the particles. The first hydrocarbon stream rich in hydrocarbons via line 121 and the first particle stream rich in the particles via line 122 can be discharged from the first separation vessel 120.
In some examples, a stripping steam stream or first stripping steam stream via line 118 can optionally be fed into the first separation vessel 120. If the stripping steam stream via line 118 is fed into the first separation vessel 120, the stripping steam stream can improve or otherwise aid in separating the first hydrocarbon stream and the first particle stream from the pyrolysis effluent. If the optional stripping steam stream via line 118 is fed into the first separation vessel 120 the first hydrocarbon stream rich in hydrocarbons discharged via line 121 can also include at least a portion of the steam. In some examples, the first separation vessel 120 can be or can include one or more cyclones configured or adapted to separate the first hydrocarbon stream and the first particle stream from the pyrolysis effluent.
The first particle stream via line 122, the heated oxidizing agent via line 110, and optionally a fuel stream via line 166 can be fed into the combustion vessel 125. In some examples, steam or other motive fluid via line 123 can be mixed, blended, or otherwise combined with the first particle stream in line 122. The fluid fed via line 123 can fluidize the particles within line 122 to urge or otherwise move the particles into the combustion vessel 125. The combustion vessel 125 can be configured or adapted to combust coke deposited onto the particles during pyrolysis of the hydrocarbon-containing feed. When the optional fuel stream via line 166 is fed into the combustion vessel 125, at least a portion of the fuel stream can be combusted. Combustion of the coke disposed on the particles and the option fuel stream within the combustion vessel 125 can produce a combustion zone effluent that can include heated particles, a flue gas, and oxidized particles in which the transition metal element has a higher oxidation state as compared to the transition metal element in the particles in the pyrolysis effluent and the first particle stream rich in the particles in line 122. The combustion vessel 125 can be configured or adapted to discharge the combustion effluent via line 126.
The combustion effluent via line 126 can be fed into the second separation vessel 130 that can be configured or adapted to receive and separate the combustion zone effluent to obtain a second particle stream rich in the particles and a first flue gas stream rich in the flue gas. The first flue gas stream via line 131 and the second particle stream via line 132 can be discharged from the second separation vessel 130. As shown in the FIGURE, the second particle stream via 132 is recycled or otherwise fed into the pyrolysis reactor 115 as the fluidized stream of particles.
In some examples, a stripping steam stream or second stripping steam stream via line 127 can optionally be fed into the second separation vessel 130. If the steam stream via line 127 is fed into the second separation vessel 130, the steam stream can improve or otherwise aid in separating the flue gas stream and the particles from the combustion effluent. In some examples, the second separation vessel 130 can be or can include one or more cyclones configured or adapted to separate the flue gas and the particles from the combustion effluent.
The first hydrocarbon stream via line 121 and a quench medium via line 162 can be fed into one or more quenching sections, e.g., a transfer line exchanger, 135 configured or adapted to produce a quenched mixture stream that includes the quench medium and the first hydrocarbon stream. The quenched mixture stream can be discharged via line 136 from the quenching section 135. In some examples, the quench medium in line 162 can be or can include a side-draw gas oil stream obtained from the distillation column 160. In other examples, a stream rich in paraffins via line 173 obtained from the recovery sub-system 170. If the stream rich in paraffins via line 173 is fed into the quenching section 125, the first hydrocarbon steam can be at a temperature sufficiently high to enable pyrolysis of at least a portion of the stream rich in paraffins upon contacting with the first hydrocarbon stream.
The quenched mixture stream via line 136 can be fed into the third separation vessel 140 configured or adapted to receive and separate the quenched mixture stream to obtain a second hydrocarbon stream rich in hydrocarbons and a third particle stream rich in the particles. In some examples, the third separation vessel 140 can be or can include one or more cyclones 141 (two are shown) configured or adapted to separate the quenched mixture stream to obtain the second hydrocarbon stream and the third particle stream. In other examples, a stripping steam stream or third stripping steam stream (not shown) can be fed into the third separation vessel 140. If the stripping steam stream is fed into the third separation vessel 140, the stripping steam stream can improve or otherwise aid in separating the second hydrocarbon stream and the third particle stream from the quenched mixture stream.
The second hydrocarbon stream via line 142 and the third particle stream via line 143 can be discharged from the third separation vessel 140. In some examples, at least a portion of the third particle stream in line 143 can be fed via line 144 into the first separation vessel 120. Feeding the third particle stream via line 144 into the first separation vessel can at least partially cool the pyrolysis effluent fed via the outlet 116 of the pyrolysis reactor 115. In other examples, at least a portion of the third particle stream in line 143 can be fed via line 144 into the combustion vessel 125 (not shown). In other examples, at least a portion of the third particle stream in line 143 can be removed via line 145 from the system 100. The removal of at least a portion of the third particle stream via line 145 can be used to control or adjust an amount of particles in the system that during operation can become undesirably rich in the transition metal element disposed thereon. In some examples, when at least a portion of the third particle stream via line 145 is removed from the system 100, starter particles via line 124 can be fed into the combustion vessel 125, for example.
The second hydrocarbon stream via line 142 can be fed into one or more optional heat exchange stages, e.g., a fourth heat exchanger, 150 configured or adapted to receive and cool the second hydrocarbon stream and discharge a cooled second hydrocarbon stream via line 151 therefrom. In some examples, a pre-heated cooling medium, e.g., a pre-heated boiler feed water, via line 167 can be fed into the fourth heat exchange stage 150 and steam via line 152 can be obtained therefrom. In some examples, the second hydrocarbon stream via line 142 or the optionally cooled hydrocarbon stream via line 151 can be fed into the distillation column 160 or optionally into one or more second quenching stages or quenching sections, e.g., a transfer line exchanger, 155. A portion of a cooled bottoms heavy oil stream via line 168 can be mixed, blended, or otherwise combined with the second hydrocarbon stream in line 142 or the optionally cooled second hydrocarbon stream in line 151 to produce a quenched second hydrocarbon stream via line 156.
The second hydrocarbon stream via line 142, the cooled second hydrocarbon stream via line 151, or the quenched second hydrocarbon stream via line 156 can be fed into the distillation column 160. The distillation column 160 can separate various hydrocarbon products from the second hydrocarbon stream in line 142, the cooled second hydrocarbon stream in line 151, or the quenched second hydrocarbon stream in line 156. In some examples, the hydrocarbon products that can be obtained from the distillation column 160 can include, but are not limited to, a bottoms heavy oil stream via line 161, a side-draw gas oil stream via line 162, an overhead stream rich in naphtha and light hydrocarbons via line 163, or a combination thereof.
In some examples, the bottoms heavy oil stream via line 161 and a cooling medium, e.g., boiler feed water, via line 164 can be fed into one or more optional heat exchange stages, e.g., a fifth heat exchanger, 165 and a cooled bottoms heavy oil stream via line 166 and the pre-heated cooling medium via line 167 can be discharged therefrom. In some examples, a portion of the cooled bottoms heavy oil stream in line 166 can be fed via line 168 into the optional quench stage 155 as the quench medium. In some examples, at least a portion of the cooled bottoms heavy oil stream via line 169 can be removed from the system 100. In some examples, at least a portion of the cooled bottoms heavy oil stream via line 166 can be fed into the combustion vessel 125 as the optional fuel stream.
The overhead stream via line 163 can be fed into the recovery sub-system 170 configured or adapted to receive and separate two or more products therefrom. In some examples, the recovery sub-system can be configured or adapted to obtain and discharge a naphtha stream via line 171, at least one olefin stream via line 172, and at least one hydrogen stream rich in hydrogen via line 174. In some examples, the recovery sub-system can also be configured or adapted to obtain and discharge the at least one paraffin stream rich in paraffins via line 173. In some examples, the paraffin stream in line 172 can include ethane, propane, butane, pentane, or any mixture thereof. In other examples, the paraffin stream in line 172 can include larger paraffins in addition to or in lieu of C2-C5 paraffins such as C6-C9 paraffins.
Returning to the first flue gas stream in line 131, the first flue gas stream via line 131 and a quench medium via line 176 can be fed into an optional quenching section 180. The quench medium in line 176 can be or can include an oxidizing agent, e.g., air. In some examples, a first portion of the oxidizing agent in line 101 can be fed into the optional heat exchange stage 105 and a second portion of the oxidizing agent in line 101 can be fed into the quenching section 180. A cooled flue gas stream via line 181 can be discharged from the quenching section 180.
The flue gas stream via line 131 or the optionally cooled flue gas stream via line 181 can be fed into the further separation vessel 185 configured or adapted to receive and separate the flue gas stream or the cooled flue gas stream to obtain a second flue gas stream rich in the flue gas and a fourth particle stream rich in the particles. In some examples, the fourth separation vessel 185 can include one or more cyclones 186 (two are shown) configured or adapted to separate the flue gas stream or the cooled flue gas stream to obtain the second flue gas stream and fourth particle stream. In other examples, a stripping steam stream or fourth stripping steam stream (not shown) can be fed into the fourth separation vessel 185. If the stripping steam stream is fed into the fourth separation vessel 185, the stripping steam stream can improve or otherwise aid in separating the second flue gas and the fourth particle stream from the flue gas stream or the cooled flue gas stream.
The second flue gas stream can be discharged via line 108 from the fourth separation vessel 185. In this example, the second flue gas stream can be or can make up at least a portion of the heat source or heated medium fed into the heat exchange stages 105, 106, and/or 107.
The fourth particle stream via line 187 can be discharged from the fourth separation vessel 185. In some examples, at least a portion of the fourth particle stream in line 187 can be removed via line 188 from the system 100. The removal of at least a portion of the fourth particle stream via line 188 can be used to control or adjust an amount of particles in the system 100 that during operation can become undesirably rich in the transition metal element disposed thereon. In some examples, when at least a portion of the fourth particle stream via line 188 is removed from the system 100, starter particles via line 124 can be fed into the combustion vessel 125, for example.
It should be understood that numerous configurations of the various processing equipment can be made. For example, the first, second, third, fourth, and fifth heat exchangers 105, 106, 107, 150, and 165 can be arranged or configured to receive the heat source or heated medium via line 108 in parallel, two or more could be integrated with one another, the heated medium fed thereto can be different heated mediums, etc. The first, second, third, fourth, and fifth heat exchangers 105, 106, 107, 150, and 165 can each independently be or include any type or combination of heat exchanger. For example, the first, second, third, fourth, and fifth heat exchangers 105, 106, 107, 150, and 165 can independently be or include shell-and-tube heat exchanger, a plate and frame heat exchanger, brazed aluminum heat exchangers, a plate and fin heat exchanger, a spiral wound heat exchanger, a coil wound heat exchanger, a U-tube heat exchanger, a bayonet style heat exchanger, any other apparatus, or any combination thereof. The separation vessels 120, 130, 140, and 185 can also be similarly configured in a number of ways. Likewise, the first and second quenching stages or quenching sections 135 and 155 can also be similarly configured in a number of ways.
This disclosure may further include the following non-limiting embodiments.
A1. A process for converting a hydrocarbon-containing feed by pyrolysis, comprising: (I) feeding the hydrocarbon-containing feed into a pyrolysis reaction zone; (II) feeding a plurality of fluidized particles having a first temperature into the pyrolysis reaction zone, wherein the first temperature is sufficiently high to enable pyrolysis of at least a portion of the hydrocarbon-containing feed on contacting the particles, and the particles comprise an oxide of a transition metal element capable of oxidizing molecular hydrogen (H2) at the first temperature; and (III) contacting at least a portion of the hydrocarbon-containing feed with the particles in the pyrolysis reaction zone to effect pyrolysis of at least a portion of the hydrocarbon-containing feed to produce a pyrolysis effluent comprising olefins, hydrogen, and the particles, wherein at least a portion of the transition metal element in the particles in the pyrolysis effluent is at a reduced state as compared to the transition metal element in the particles fed into the pyrolysis reaction zone.
A2. The process of A1, wherein the transition metal element is selected from oxides of titanium, vanadium, chromium, manganese, iron, cobalt, niobium, nickel, molybdenum, tantalum, tungsten, alloys thereof, and mixtures thereof.
A3. The process of A2, wherein the transition metal element is selected from oxides of vanadium, chromium, manganese, iron, cobalt, nickel, and mixtures thereof.
A4. The process of A1 to A3, wherein the oxide of the transition metal element has a concentration in a range from 500 ppmw to 50 wt %, based on the total weight of the particles.
A5. The process of any of A1 to A4, wherein the oxide of the transition metal element favors the oxidation of molecular hydrogen over the combustion of hydrocarbons contained in the pyrolysis reaction zone.
A6. The process of any of A1 to A5, wherein the particles comprise inert cores and a surface layer comprising the oxide of the transition metal element.
A7. The process of A6, wherein the inert cores comprise silica, alumina, zirconia, and mixtures and combinations thereof.
A8. The process of any of A1 to A7, wherein the hydrocarbon-containing feed comprises the transitional metal element contained in the particles, and at least a portion of the transition metal element contained in the particles is derived from the metal element contained in the hydrocarbon-containing feed.
A9. The process of any of A1 to A8, wherein the weight ratio of the particles to the hydrocarbon-containing feed is in a range from 10:1 to 50:1, preferably from 15:1 to 50:1, more preferably from 20:1 to 50:1.
A10. The process of any of A1 to A9, wherein the particles have an average size in a range from 25 to 500 micrometers.
A11. The process of any of A1 to A10, further comprising: (IV) optionally steam stripping the pyrolysis effluent using a first stripping steam stream; (V) obtaining from the pyrolysis effluent and the optional first stripping steam stream a first hydrocarbon stream rich in hydrocarbons and a first particle stream rich in the particles; (VI) oxidizing and heating at least a portion of the particles in the first particle stream in a combustion zone such that at least a portion of the transition metal element in the particles is oxidized to a higher oxidation state compared to the transition metal element in the particles in the pyrolysis effluent; and (VII) feeding at least a portion of the heated and oxidized particles to the pyrolysis reaction zone as at least a portion of the particles fed into the pyrolysis reaction zone in step (II).
A12. The process of A11, wherein step (IV) is performed.
A13. The process of A11 or A12, wherein the process further comprises, after step (VI) and before step (VII), the following step (VIa) steam stripping at least a portion of the heated and oxidized particles.
A14. The process of any of A11 to A13, wherein in step (VI), a combustion zone effluent comprising the heated and oxidized particles and a flue gas is produced, and the process further comprise, after step (VI) and before step (VII), the following steps: (VIb) separating the combustion zone effluent into a second particle stream rich in the heated and oxidized particles and a first flue gas stream rich in the flue gas; (VIc) separating the particles, if any, contained in the first flue gas stream using a cyclone; and (VId) feeding at least a portion of the particles separated in step (VIc) to the combustion zone.
A15. The process of any of A11 to A14, wherein at least a portion of the particles fed into the pyrolysis reaction zone in step (II) is formed by: (VIII) feeding a plurality of starter particles into the pyrolysis reaction zone; (IX) feeding a source material for the transition metal element into the pyrolysis reaction zone; (X) contacting the starter particles with the source material for the transition metal element in the pyrolysis reaction zone to obtain a contacting mixture effluent comprising the starter particles having a layer of the source material for the transition metal element deposited thereon; and (XI) heating and oxidizing at least a portion of the starter particles having the layer of the source material for the transition metal element in the combustion zone to form the particles comprising the transition metal element.
A16. The process of A15, wherein the source material for the transition metal element in step (IX) is present in the hydrocarbon-containing feed.
A17. The process of any of A1 to A16, wherein at least a portion of the particles are derived from a fluid catalytic converter catalyst.
A18. The process of any of A15 or A17, wherein at least a portion of the starter particles are derived from a fluid catalytic converter catalyst.
A19. The process of any of A14 to A18, wherein in step (VI) oxidizing and heating the at least a portion of the particles in the first particle stream in the combustion zone is done in the presence of an oxidizing agent.
A20. The process of A19, wherein a feeding rate of the oxidizing agent introduced into the combustion zone is adjusted so that the flue gas contains at least 1 mol % of carbon monoxide.
A21. The process of A19, wherein a feeding rate of the oxidizing agent introduced into the combustion zone is adjusted so that the flue gas contains at least a portion of the oxidizing agent and less than 1 mol % of carbon monoxide.
A22. The process of any of A11 to A21, wherein in step (III), coke is formed on the surface of the particles, and in step (VI), at least a portion of the coke on the surface of the particles is combusted.
A23. The process of any of A1 to A22, wherein the hydrocarbon-containing feed comprises a resid.
A24. The process of any of A1 to A23, wherein the first temperature is in a range from 800° C. to 1400° C.
A25. The process of any of A1 to A24, wherein the hydrocarbon-containing feed has a temperature in a range from 100° C. to 400° C.
A26. The process of any of A1 to A25, further comprising (Ia) feeding steam into the pyrolysis reaction zone.
A27. The process of A26, wherein the weight ratio of the steam fed into the pyrolysis reaction zone to the hydrocarbon-containing feed is in a range from 0.2:1 to 1:1.
A28. The process of any of A1 to A27 wherein the contacting in the pyrolysis reaction zone in step (III) has a residence time from 10 milliseconds to 500 milliseconds.
A29. The process of any of A1 to A28, wherein the contacting in the pyrolysis reaction zone in step (III) is performed under an absolute pressure from 101 to 800 kPa.
A30. The process of any of A1 to A29, wherein the pyrolysis effluent has a temperature in a range from 800° C. to 1,200° C. upon exiting the pyrolysis reaction zone.
A31. The process of any of A1 to A30, wherein the pyrolysis reaction zone is located in a downflow reactor.
A32. The process of any of A11 to A31, further comprising: (XII) quenching the first hydrocarbon stream.
A33. The process of A32, wherein the first hydrocarbon stream has a temperature in a range from 650° C. to 1,200° C. immediately before quenching.
A34. The process of A32 or A33, wherein the time from the contacting in step (III) in the pyrolysis reactor to the quenching in step (XII) is in a range from 10 to 2000 milliseconds.
A35. The process of any of A32 to A34, wherein step (XII) comprises contacting the hydrocarbon stream with a quench medium to produce a cooled hydrocarbon stream.
A36. The process of A35, wherein the quench medium comprises a stream rich in paraffins.
A37. The process of A36, and wherein the first hydrocarbon stream is at a temperature sufficient to effect pyrolysis of at least a portion of the stream rich in paraffins.
A38. The process of any of A35 to A37, wherein the first hydrocarbon stream is at a temperature of 650° C. to 1,100° C. when initially contacted with the quench medium.
A39. The process of any of 35, wherein the quench medium comprises one or more C2-C9 alkanes, and wherein at least 1 wt % of the one or more C2-C9 alkanes in the quench medium is pyrolyzed to produce olefins, aromatic hydrocarbons, or a mixture thereof.
A40. The process of any of A32 to A39, further comprising: (XIII) separating the quenched first hydrocarbon stream to obtain a second hydrocarbon stream rich in hydrocarbons and a third particle stream rich in the particles; and (XIV) recycling at least a portion of the particles in the third particle stream to the combustion zone.
A41. The process of any of A40, further comprising: (XV) obtaining from the second hydrocarbon stream a gas oil stream and a bottoms heavy stream.
A42. The process of A41, further comprising at least one of the following steps: (XVI) quenching the first hydrocarbon stream at least partly using at least a portion of the gas oil stream; and (XVII) feeding at least a portion of the bottoms heavy stream to the combustion zone as a fuel for oxidation.
A43. The process of A41 or A42, further comprising: (XVII) obtaining from the second hydrocarbon stream at least one of the following: (i) a naphtha stream, (ii) an olefin stream rich in an olefin, and (iii) a stream rich in hydrogen.
A44. The process of any of A1 to A43, wherein the hydrocarbon-containing feed is produced by: (Ia) feeding a raw feed into a flashing drum; (Ib) obtaining an overhead vapor effluent and a bottoms liquid effluent from the flashing drum; and (Ic) obtaining the hydrocarbon-containing feed from the bottoms liquid effluent.
A45. The process of A44, wherein the raw feed comprises a crude, an atmospheric resid, and/or a vacuum resid.
A46. The process of A44 or A45, wherein a cutoff point of the bottoms liquid effluent is from 300° C. to 700° C.
A47. The process of any of A44 to A46, further comprising feeding at least a portion of the overhead vapor effluent to a steam cracker.
B1. A process for converting a hydrocarbon-containing feed by pyrolysis, the process comprising: (I) feeding the hydrocarbon-containing feed to a pyrolysis reaction zone, wherein the hydrocarbon-containing feed comprises a first transition metal element; (II) feeding a plurality of fluidized particles having a first temperature into the pyrolysis reaction zone, wherein the first temperature is sufficiently high to enable pyrolysis of at least a portion of the hydrocarbon-containing feed on contacting the particles, and the particles comprise an oxide of a second transition metal element capable of oxidizing molecular hydrogen (H2) at the first temperature; (III) contacting at least a portion of the hydrocarbon-containing feed with the particles in the pyrolysis reaction zone to effect pyrolysis of at least a portion of the hydrocarbon-containing feed to produce a pyrolysis effluent comprising olefins, hydrogen, and the particles, wherein at least a portion of the second transition metal element in the particles in the pyrolysis effluent is at a reduced state compared to the transition metal element in the particles fed into the pyrolysis reaction zone, and wherein at least a portion of the first transition metal element in the hydrocarbon-containing feed deposits onto the particles; (IV) optionally steam stripping the pyrolysis effluent using a stripping steam stream; (V) obtaining from the pyrolysis effluent optionally admixed with the stripping steam stream a first hydrocarbon stream rich in hydrocarbons and a first particle stream rich in the particles; (VI) oxidizing and heating at least a portion of the particles in the first particle stream in a combustion zone such that at least a portion of the second transition metal element in the particles is oxidized to a higher oxidation state compared to the second transition metal element in the particles in the pyrolysis effluent; and (VII) feeding at least a portion of the heated and oxidized particles to the pyrolysis reaction zone as at least a portion of the particles fed into the pyrolysis reaction zone in step (II).
B2. The process of B1, wherein the oxide of the second transition metal element favors the oxidation of molecular hydrogen over the combustion of hydrocarbons contained in the pyrolysis reaction zone.
B3. The process of B1 or B2, wherein oxidizing and heating the at least a portion of the particles in the first particle stream in the combustion zone oxidizes at least a portion of the first transition metal element deposited on the particles to a higher oxidation state compared to the first transition metal element on the particles in the pyrolysis effluent.
B4. The process of any of B1 to B3, further comprising (VIII) contacting the first hydrocarbon stream with a quench medium to produce a cooled hydrocarbon stream.
B5. The process of B4, wherein the quench medium comprises a stream rich in paraffins.
B6. The process of B5, wherein the first hydrocarbon stream is at a temperature sufficient to effect pyrolysis of at least a portion of the one or more paraffins in the stream rich in paraffins.
B7. The process of any of B4 to B6, wherein the first hydrocarbon stream is at a temperature of 650° C. to 1,100° C. when initially contacted with the quench medium.
B8. The process of B6 or B7, wherein at least 1 wt % of the one or more C2-C9 alkanes in the quench medium is pyrolyzed to produce olefins, aromatic hydrocarbons, or a mixture thereof.
B9. The process of any of B1 to B8, wherein the first transition metal element and the second transition metal element are each selected from oxides of titanium, vanadium, chromium, manganese, iron, cobalt, niobium, nickel, molybdenum, tantalum, tungsten, alloys thereof, and mixtures thereof.
B10. The process of any of B1 to B9, wherein the oxide of the second transition metal element has a concentration in a range from 500 ppmw to 50 wt %, based on the total weight of the particles.
B11. The process of any of B1 to B10, wherein the particles comprise inert cores and a surface layer comprising the oxide of the second transition metal element.
B12. The process of any of B1 to B12, wherein the inert cores comprise silica, alumina, zirconia, and mixtures or combinations thereof.
B13. The process of any of B1 to B12, wherein the weight ratio of the particles to the hydrocarbon-containing feed is in a range from 10:1 to 50:1, preferably from 15:1 to 50:1, more preferably from 20:1 to 50:1.
B14. The process of any of B1 to B13, wherein the particles have an average size in a range from 25 to 500 micrometers.
B15. The process of any of B1 to A14, wherein at least a portion of the particles are derived from a fluid catalytic converter catalyst.
B16. The process of any of B1 to B15, wherein in step (III), coke is formed on the surface of the particles, and in step (VI), at least a portion of the coke on the surface of the particles is combusted.
B17. The process of any of B1 to B16, wherein the hydrocarbon-containing feed comprises a resid.
B18. The process of any of B1 to B17, wherein the contacting in the pyrolysis reaction zone in step (III) has a residence time from 10 milliseconds to 500 milliseconds.
B19. The process of any of B1 to B18, wherein the hydrocarbon-containing feed is produced by: (Ia) feeding a raw feed into a flashing drum; (Ib) obtaining an overhead vapor effluent and a bottoms liquid effluent from the flashing drum; and (Ic) obtaining the hydrocarbon-containing feed from the bottoms liquid effluent.
B20. The process of B19, wherein the raw feed comprises a crude, an atmospheric resid, and/or a vacuum resid.
B21. The process of B19 or B20, wherein a cutoff point of the bottoms liquid effluent is from 300° C. to 700° C.
B22. The process of any of B19 to B21, further comprising feeding at least a portion of the overhead vapor effluent to a steam cracker.
B23. The process of any of B1 to B22, wherein in step (VI) oxidizing and heating the at least a portion of the particles in the first particle stream in the combustion zone is done in the presence of an oxidizing agent.
B24. The process of B23, wherein a feeding rate of the oxidizing agent introduced into the combustion zone is adjusted so that the flue gas contains at least 1 mol % of carbon monoxide.
B25. The process of B23, wherein a feeding rate of the oxidizing agent introduced into the combustion zone is adjusted so that the flue gas contains at least a portion of the oxidizing agent and less than 1 mol % of carbon monoxide.
C1. A system for converting a hydrocarbon-containing feed by pyrolysis, the system comprising: (i) a pyrolysis reactor adapted for receiving the hydrocarbon-containing feed and a fluidized stream of particles having a first temperature, and allowing the hydrocarbon-containing feed to contact the particles to effect pyrolysis of at least a portion of the hydrocarbon-containing feed, wherein the first temperature is sufficiently high to enable pyrolysis of at least a portion of the hydrocarbon-containing feed, and wherein the particles comprise an oxide of a transition metal element capable of oxidizing molecular hydrogen (H2) at the first temperature, and discharging a pyrolysis effluent; (ii) a first separation vessel adapted for receiving the pyrolysis effluent, optionally receiving a stripping steam stream, separating the pyrolysis effluent to obtain a first hydrocarbon stream rich in hydrocarbons and a first particle stream rich in the particles, discharging the first hydrocarbon stream, and discharging the first particle stream; (iii) a combustion vessel adapted for receiving a stream of an oxidizing agent, receiving at least a portion of the first particle stream, optionally receiving a fuel stream, optionally combusting the fuel, combusting at least a portion of any coke disposed on the particles, heating the particles, oxidizing the particles, and discharging a combustion zone effluent comprising the heated and oxidized particles and a flue gas; (iv) a second separation vessel adapted for receiving the combustion zone effluent, separating the combustion zone effluent to obtain a second particle stream rich in the particles and a first flue gas stream rich in the flue gas, discharging the second particle stream, and discharging the first flue gas stream; and (v) a channel adapted for feeding at least a portion of the second particle stream to the pyrolysis reactor.
C2. The system of C1, wherein the pyrolysis reactor is a downflow reactor.
C3. The system of C1 or C2, wherein the first separation vessel is further adapted for receiving a steam stream, and stripping the particles contained therein.
C4. The system of any of C1 to C3, wherein the second separation vessel is further adapted for receiving a steam stream, and stripping the particles contained therein.
C5. The system of any of C1 to C4, further comprising: (vi) a quenching section downstream of the first separation vessel adapted for receiving the first hydrocarbon stream, receiving a stream of a quenching medium, and discharging a quenched mixture stream comprising the quenching medium and the first hydrocarbon stream; (vii) a third separation vessel comprising a cyclone, wherein the third separation vessel is adapted for receiving the quenched mixture stream, separating the quenched mixture stream to obtain a third particle stream rich in the particles and a second hydrocarbon stream rich in hydrocarbons, discharging the third particle stream, and discharging the second hydrocarbon stream; and (viii) a channel adapted for feeding at least a portion of the third particle stream to the first separation vessel or to the combustion vessel.
C6. The system of any of C1 to C5, further comprising: (ix) an optional heat exchanger adapted for receiving the second hydrocarbon stream, cooling the second hydrocarbon stream rich in hydrocarbons, and discharging a cooled second hydrocarbon stream rich in hydrocarbons; (x) a distillation column adapted for receiving the second hydrocarbon stream or the optionally cooled second hydrocarbon stream, separating the second hydrocarbon stream to obtain a bottoms heavy oil stream, and a side-draw gas oil stream.
C7. The system of C6, further comprising: (xi) a channel adapted for feeding at least a portion of the side-draw gas oil stream to the quenching zone as at least a portion of the quenching medium.
C8. The system of C6 or C7, further comprising: (xii) a channel adapted for feeding at least a portion of the bottoms heavy oil stream to the combustion zone as at least a portion of the fuel.
C9. The system of any of C6 to C8, wherein the distillation column is further adapted for discharging an overhead stream rich in naphtha and light hydrocarbons, and the system further comprises: (xiii) a recovery sub-system adapted for receiving the overhead stream, separating the overhead stream, discharging a naphtha stream, discharging at least one olefin stream rich in an olefin, and discharging at least one hydrogen stream rich in hydrogen.
C10. The system of any of C1 to C9, further comprising: (xiv) a fourth separation vessel comprising a cyclone, wherein the fourth separation vessel is adapted for receiving the first flue gas stream, separating the first flue gas stream to obtain a second flue gas stream rich in the flue gas and a fourth particle stream rich in the particles, discharging the second flue gas stream, and discharging the fourth particle stream; and (xv) a channel adapted for feeding at least a portion of the fourth particle stream to the combustion vessel.
C11. The system of C10, further comprising: a heat exchanger adapted for heating the hydrocarbon-containing feed to produce a heated hydrocarbon-containing feed by transferring heat from the second flue gas stream rich in the flue gas to the hydrocarbon-containing feed; and a channel adapted for feeding at least a portion of the second flue gas stream into the heat exchanger adapted for heating the hydrocarbon-containing feed.
Various terms have been defined above. To the extent a term used in a claim is not defined above, it should be given the broadest definition persons in the pertinent art have given that term as reflected in at least one printed publication or issued patent. Furthermore, all patents, test procedures, and other documents cited in this application are fully incorporated by reference to the extent such disclosure is not inconsistent with this application and for all jurisdictions in which such incorporation is permitted.
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
| Number | Date | Country | Kind |
|---|---|---|---|
| 19199560.4 | Sep 2019 | EP | regional |
This application claims priority to and the benefit of U.S. Ser. No. 62/882,218, filed Aug. 2, 2019, and European Patent Application No. 19199560.4, filed Sep. 25, 2019, the disclosures of which are incorporated herein by their reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2020/044137 | 7/30/2020 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 62882218 | Aug 2019 | US |
