Systems and methods for producing olefins

Abstract

According to one or more embodiments, an olefin can be produced by contacting a hydrocarbon feed stream with a particulate solid in a reaction vessel. The reaction vessel can be connected to a riser. The riser can extend through a riser port of a shell of a particulate solid separation section, such that the riser can include an inner riser section and an outer riser section. The particulate solid separation section can include a gas outlet port, a riser port, and a particulate solid outlet port. The particulate solid separation section can house a gas / solid separation device and a solid particle collection area. The riser port can be positioned on a sidewall of the shell, such that the riser port is not located on a central vertical axis of the particulate solid separation section. The particulate solid can be separated from an olefin-containing product stream in the gas / solid separation device.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit and priority of U.S. Application Serial No. 63 / 126,095, filed on December 16, 2020, entitled “Systems and Methods for Producing Olefins,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The embodiments described herein generally involve chemical processing, and more specifically, methods and systems for catalytic chemical transformation. Background Technology

[0004] Light olefins can be used as base materials to produce many types of goods and materials. For example, ethylene can be used to manufacture polyethylene, ethylene chloride, or ethylene oxide. These products are used in product packaging, construction, textiles, and so on. Therefore, light olefins, such as ethylene, propylene, and butene, are industrially needed. Light olefins can be produced through different reaction processes depending on a given chemical feed stream, which can be a product stream from crude oil refining operations. Many light olefins can be produced using processes employing particulate solids, such as solid particulate catalysts. Summary of the Invention

[0005] Some reactor systems used to process hydrocarbon feedstocks to produce olefins include a reaction vessel positioned directly below a particulate solids separation section, with a riser (connecting the reaction vessel to the separation section) extending from the reaction vessel through the bottom of the particulate solids separation section. This design can adversely affect the flow of particulate solids through the particulate solids separation section by creating an annular space in the bottom portion of the section, in which the outlet cannot be centered at the bottom. Additionally, this design may result in a riser that is longer than required, potentially allowing undesirable side reactions that could reduce the yield of light olefins. Furthermore, this design can lead to more expensive process equipment, as the internal riser may require advanced materials, and the bottom of the separation section may have a larger diameter to account for the volume occupied by the internal riser. Improved methods and improved system components for olefin production are needed.

[0006] This invention discloses methods and systems for producing olefins that address problems identified in prior designs. In one or more embodiments, the riser does not enter the particulate solids separation section through the bottom, thereby improving the flow characteristics of particulate solids leaving the separation section. Additionally, in the embodiments disclosed herein, the riser can have a shorter length compared to a riser that enters through the bottom of the particulate solids separation section. This can reduce residence time, during which side reactions that reduce the yield of light olefins may occur.

[0007] According to one or more embodiments disclosed herein, olefins can be produced by a method comprising contacting a hydrocarbon feed stream with particulate solids in a reaction vessel. Contacting the hydrocarbon feed stream with the particulate solids allows the hydrocarbon feed stream to react to form an olefin-containing product stream. The reaction vessel may be connected to a riser, and the reaction vessel may have a maximum cross-sectional area at least three times the maximum cross-sectional area of ​​the riser. The method may further include conveying the particulate solids through the riser. The riser may extend through a riser port of a shell of a particulate solids separation section, such that the riser may include an inner riser segment located in an inner region of the particulate solids separation section and an outer riser segment located outside the shell of the particulate solids separation section. The particulate solids separation section may include at least a shell defining an inner region of the particulate solids separation section. The shell may include a gas outlet port, a riser port, and a particulate solids outlet port. The shell may house a gas / solid separation device and a solid particle collection area within the inner region of the particulate solids separation section. The riser port can be positioned on the side wall of the housing such that it is not located on the central vertical axis of the particulate solids separation section. The method may further include separating the particulate solids from the olefin-containing product stream in the gas / solid separation device, and conveying the separated particulate solids to a solid particle collection area located near the central vertical axis of the particulate solids separation section.

[0008] It should be understood that both the foregoing summary and the following detailed description present embodiments of the present technology and are intended to provide an overview or framework for understanding the nature and features of the claimed technology. Drawings are included to provide further understanding of the technology, and these drawings are incorporated in and form part of this specification. The drawings illustrate various embodiments and, together with the description, serve to explain the principles and operation of the technology. Furthermore, the drawings and description are intended to be illustrative only and are not intended to limit the scope of the claims in any way.

[0009] Further features and advantages of the invention disclosed herein will be set forth in the following detailed description, and will be apparent in part from the description or recognized by practice of the invention as described herein, including the following detailed description, claims and drawings. Attached Figure Description

[0010] The following detailed description of specific embodiments of this disclosure is best understood in conjunction with the following drawings, in which similar reference numerals indicate similar structures and in the drawings:

[0011] Figure 1 A reactor system comprising a reactor section and a regenerator section according to one or more embodiments disclosed herein is schematically depicted;

[0012] Figure 2 A reaction vessel and an external riser segment are schematically depicted according to one or more embodiments disclosed herein;

[0013] Figure 3 A particulate solids separation section according to one or more embodiments disclosed herein is schematically depicted;

[0014] Figure 4 A solid particle collection region according to one or more embodiments disclosed herein is depicted;

[0015] Figure 5 A solid particle collection region according to one or more embodiments disclosed herein is depicted; and

[0016] Figure 6 The residence time distribution of a solid particle collection area according to one or more embodiments disclosed herein is depicted graphically.

[0017] It should be understood that the accompanying drawings are schematic in nature and do not include some components commonly used in fluid catalytic reactor systems in the art, such as, but not limited to, temperature transmitters, pressure transmitters, flow meters, pumps, valves, etc. These components are well known to be within the spirit and scope of the disclosed embodiments. However, operating components (such as those described in this disclosure) may be added to the embodiments described in this disclosure.

[0018] Reference will now be made in more detail to various embodiments, some of which are shown in the accompanying drawings. Where possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts. Detailed Implementation

[0019] This document discloses a method for producing olefins from a hydrocarbon feed stream. Such methods utilize systems with specific characteristics, such as the specific orientation of system components. For example, in one or more embodiments described herein, the reaction vessel is not directly located below the separation section. A specific embodiment disclosed in detail herein is depicted in… Figure 1 However, it should be understood that the principles disclosed and taught herein can be applied to other systems utilizing different system components oriented in different ways, or to different reaction schemes utilizing various catalyst compositions.

[0020] Now for reference Figure 1 As will be understood with reference to the foregoing figures and description, the feed chemicals can react by contacting particulate solids, such as catalysts, in reactor section 200. The particulate solids can be separated from the reaction products in reactor section 200 and conveyed to regeneration section 300. In regeneration section 300, the particulate solids can be regenerated. These regenerated particulate solids can then be conveyed back to reactor section 200 for subsequent reaction cycles.

[0021] While some embodiments are described herein in the context of reactor system 100, it should be understood that the methods and systems described herein can be operated without the regeneration section 300, or using alternative means for regenerating particulate solids. Therefore, the regeneration section 300 should not be construed as necessary or required in all embodiments of the currently disclosed methods and systems.

[0022] In a non-limiting example, the reactor system 100 described herein can be used to produce light olefins from a hydrocarbon feed stream. Light olefins can be produced using various hydrocarbon feed streams with different reaction mechanisms. For example, light olefins can be produced by at least dehydrogenation, cracking, dehydration, and methanol-to-olefins reactions. These reaction types can utilize different feed streams and different particulate solids to produce light olefins. It should be understood that when “catalyst” is mentioned herein, the catalyst can also refer to… Figure 1 The system refers to granular solids.

[0023] According to one or more embodiments, the reaction can be a dehydrogenation reaction. According to such embodiments, the hydrocarbon feed stream can contain one or more of ethylbenzene, ethane, propane, n-butane, and isobutane. In one or more embodiments, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of ethylbenzene. In one or more embodiments, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of ethane. In another embodiment, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of propane. In another embodiment, the hydrocarbon feed stream may contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of n-butane. In another embodiment, the hydrocarbon feed stream may contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of isobutane. In another embodiment, the hydrocarbon feed stream may contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of the sum of ethane, propane, n-butane, and isobutane.

[0024] In one or more embodiments, the dehydrogenation reaction may utilize gallium and / or platinum particulate solids as catalysts. In such embodiments, the particulate solids may comprise gallium and / or platinum catalysts. As described herein, gallium and / or platinum catalysts comprise gallium, platinum, or both. Gallium and / or platinum catalysts may be supported on an alumina or alumina-silica support and may optionally include potassium. Such gallium and / or platinum catalysts are disclosed in U.S. Patent No. 8,669,406, which is incorporated herein by reference in its entirety. However, it should be understood that other suitable catalysts may be used for the dehydrogenation reaction.

[0025] In one or more embodiments, the reaction mechanism may be dehydrogenation followed by combustion (in the same chamber). In such embodiments, the dehydrogenation reaction can produce hydrogen as a byproduct, and the oxygen-carrying material can contact the hydrogen and facilitate its combustion, thereby forming water. Examples of such reaction mechanisms are disclosed in WO 2020 / 046978, which are considered possible reaction mechanisms for the systems and methods described herein, the teachings of which are incorporated herein by reference in their entirety.

[0026] According to one or more embodiments, the reaction can be a cracking reaction. According to such embodiments, the hydrocarbon feed stream can contain one or more of naphtha, n-butane, or isobutane. According to one or more embodiments, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of naphtha. In another embodiment, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of n-butane. In another embodiment, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of isobutane. In another embodiment, the hydrocarbon feed stream may contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of naphtha, n-butane, and isobutane.

[0027] In one or more embodiments, the cracking reaction may utilize one or more zeolites as catalysts. In such embodiments, the particulate solids may include one or more zeolites. In some embodiments, the one or more zeolites used in the cracking reaction may include ZSM-5 zeolite. However, it should be understood that other suitable catalysts may be used for the cracking reaction. For example, commercially available suitable catalysts may include Intercat Super Z Excel or Intercat Super Z Exceed. In another embodiment, in addition to the catalytically active material, the cracking catalyst may also include platinum. For example, the cracking catalyst may include 0.001 wt.% to 0.05 wt.% platinum. Platinum may be sprayed in the form of platinum nitrate and calcined at elevated temperatures (such as about 700°C). Without being bound by theory, it is believed that the addition of platinum to the catalyst may allow for easier combustion of supplemental fuels such as methane.

[0028] According to one or more embodiments, the reaction can be a dehydration reaction. According to such embodiments, the hydrocarbon feed stream can contain one or more of ethanol, propanol, or butanol. According to one or more embodiments, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of ethanol. In another embodiment, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of propanol. In another embodiment, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of butanol. In another embodiment, the hydrocarbon feed stream may contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of the total of ethanol, propanol, and butanol.

[0029] In one or more embodiments, the dehydration reaction may utilize one or more acid catalysts. In such embodiments, the particulate solid may comprise one or more acid catalysts. In some embodiments, the one or more acid catalysts used in the dehydration reaction may comprise zeolites (such as ZSM-5 zeolite), alumina, amorphous aluminosilicates, acidic clays, or combinations thereof. For example, according to one or more embodiments, potentially suitable commercially available alumina catalysts include SynDol (available from Scientific Design Company), V200 (available from UOP), or P200 (available from Sasol). Potentially suitable commercially available zeolite catalysts include CBV 8014 and CBV 28014 (each available from Zeolyst). Potentially suitable commercially available amorphous aluminosilicate catalysts include silica-alumina catalyst supports, grade 135 (available from Sigma-Aldrich). However, it should be understood that other suitable catalysts may be used for the dehydration reaction.

[0030] According to one or more embodiments, the reaction can be a methanol-to-olefins reaction. According to such embodiments, the hydrocarbon feed stream can contain methanol. According to one or more embodiments, the hydrocarbon feed stream can contain at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.%, or even at least 99 wt.% of methanol.

[0031] In one or more embodiments, the methanol-to-olefins reaction can utilize one or more zeolites as catalysts. In such embodiments, the particulate solids may include one or more zeolites. In some embodiments, the one or more zeolites used in the methanol-to-olefins reaction may include one or more of ZSM-5 zeolite or SAPO-34 zeolite. However, it should be understood that other suitable catalysts can be used for the methanol-to-olefins reaction.

[0032] In one or more embodiments, the operation of the chemical process may include discharging a product stream from a reactor. The product stream may contain light olefins or alkyl aromatic olefins, such as styrene. As described herein, “light olefin” means one or more of ethylene, propylene, or butene. As described herein, butene may include any isomer of butene, such as α-butene, cis-β-butene, trans-β-butene, and isobutene. In one embodiment, the product stream may contain at least 50 wt.% light olefins. For example, the product stream may contain at least 60 wt.% light olefins, at least 70 wt.% light olefins, at least 80 wt.% light olefins, at least 90 wt.% light olefins, at least 95 wt.% light olefins, or even at least 99 wt.% light olefins.

[0033] Still referencing Figure 1 The reactor system 100 typically includes multiple system components, such as the reactor section 200 and the regeneration section 300. As described herein... Figure 1As used in the context, reactor section 200 generally refers to the portion of reactor system 100 where the main process reaction takes place and particulate solids are separated from the olefin-containing product stream of the reaction. In one or more embodiments, the particulate solids may be used, meaning they are at least partially deactivated. Furthermore, as used herein, regeneration section 300 generally refers to the portion of a fluid catalytic reactor system where particulate solids are regenerated, such as by combustion, and the regenerated particulate solids are separated from other process materials, such as gases released from previously burned materials on used particulate solids or from supplementary fuel. Reactor section 200 generally includes a reaction vessel 250, a riser 230 including an external riser section 232 and an internal riser section 234, and a particulate solids separation section 210. Regeneration section 300 generally includes a particulate solids handling vessel 350, a riser 330 including an external riser section 332 and an internal riser section 334, and a particulate solids separation section 310. Typically, the particulate solids separation section 210 can be in fluid communication with the particulate solids processing container 350, for example, via the riser 126, and the particulate solids separation section 310 can be in fluid communication with the reaction container 250, for example, via the riser 124 and the conveying riser 130.

[0034] Typically, reactor system 100 can be operated by feeding hydrocarbon feed and fluidized particulate solids into reaction vessel 250, and reacting the hydrocarbon feed with the fluidized particulate solids to produce an olefin-containing product in reaction vessel 250 of reactor section 200. The olefin-containing product and particulate solids can exit from reaction vessel 250 and reach gas / solid separator 220 in particulate solids separation section 210 via riser 230, where the particulate solids can be separated from the olefin-containing product. The particulate solids can then be conveyed from particulate solids separation section 210 to particulate solids processing vessel 350. In particulate solids processing vessel 350, the particulate solids can be regenerated by chemical processes. For example, used particulate solids can be regenerated by one or more of the following methods: oxidizing the particulate solids by contacting with oxygen-containing gas, burning coke present on the particulate solids, and burning supplementary fuel to heat the particulate solids. The particulate solids can then exit from the particulate solids processing container 350 and reach the riser terminal device 378 via the riser 330, where the gas and particulate solids from the riser 330 are partially separated. The gas from the riser 330 and the remaining particulate solids are conveyed to the gas / solid separator 320 in the particulate solids separation section 310, where the remaining particulate solids are separated from the gas from the regeneration reaction. The particulate solids separated from the gas can be conveyed to the solid particle collection area 380. The separated particulate solids are then conveyed from the solid particle collection area 380 to the reaction vessel 250, where they are further utilized. Thus, the particulate solids can be circulated between the reactor section 200 and the regeneration section 300.

[0035] In one or more embodiments, reactor system 100 may include reactor section 200 or regeneration section 300, but not both. In another embodiment, reactor system 100 may include a single regeneration section 300 and multiple reactor sections 200.

[0036] Furthermore, as described herein, the structural features of reactor section 200 and regeneration section 300 may be similar or identical in some respects. For example, each of reactor section 200 and regeneration section 300 includes a reaction vessel (i.e., reaction vessel 250 of reactor section 200 and particulate solids handling vessel 350 of regeneration section 300), a riser (i.e., riser 230 of reactor section 200 and riser 330 of regeneration section 300), and a particulate solids separation section (i.e., particulate solids separation section 210 of reactor section 200 and particulate solids separation section 310 of regeneration section 300). It should be understood that, since many structural features in the reactor section 200 and the regeneration section 300 may be similar or identical in some respects, similar or identical portions of the reactor section 200 and the regeneration section 300 are provided throughout this disclosure with the same last two digits of reference numerals, and the disclosure relating to a portion of the reactor section 200 may be applied to similar or identical portions of the regeneration section 300, and vice versa.

[0037] like Figure 1 and Figure 2 As depicted, reaction vessel 250 may include a reaction vessel particulate solids inlet port 252 defining the connection between the delivery riser 130 and the reaction vessel 250. Reaction vessel 250 may additionally include a reaction vessel outlet port 254 in fluid communication with or directly connected to an external riser segment 232 of the riser 230. As described herein, "reaction vessel" refers to a drum, barrel, vat, or other container suitable for a given chemical reaction. The shape of a reaction vessel may be generally cylindrical (i.e., having a substantially circular diameter), or alternatively, may be non-cylindrical, such as a prism shape having a triangular, rectangular, pentagonal, hexagonal, octagonal, elliptical, or other polygonal, or curved closed, or combined thereof cross-sectional shape. As used throughout this disclosure, reaction vessels typically include a metal frame and may additionally include a refractory lining or other materials for protecting the metal frame and / or controlling process conditions.

[0038] Generally, the terms "inlet port" and "outlet port" for any system unit of the fluid catalytic reactor system 100 described herein refer to an opening, hole, channel, pore, gap, or other similar mechanical feature within the system unit. For example, an inlet port allows material to enter a particular system unit, and an outlet port allows material to exit a particular system unit. Typically, an outlet port or inlet port defines an area of ​​the system unit of the fluid catalytic reactor system 100 to which a pipe, conduit, tube, hose, delivery line, or similar mechanical feature is attached, or defines a portion of the system unit to which another system unit is directly attached. While inlet and outlet ports may sometimes be described herein as functionally operable, they may have similar or identical physical properties, and their respective functions within an operable system should not be construed as limiting their physical structure. Other ports (such as riser port 218) may include openings in a given system unit to which other system units are directly attached, such as where riser 230 extends from riser port 218 into the particulate solids separation section 210.

[0039] The reaction vessel 250 can be connected to a feed riser 130, which, during operation, supplies the regenerated particulate solids and chemical feed to the reactor section 200. For example... Figure 2 As shown, the regenerated particulate solids and chemical feedstock can be mixed using a distributor 260 housed within reaction vessel 250. (See again...) Figure 1 Particulate solids entering the reaction vessel 250 via the conveyor riser 130 can reach the conveyor riser 130 via the riser 124, thus reaching the regeneration section 300. In some embodiments, the particulate solids can directly enter the particulate solids separation section 210 via the riser 122, where they enter the reaction vessel 250. These particulate solids may be slightly deactivated, but in some embodiments, they may still be suitable for use in the reaction vessel 250.

[0040] like Figure 1 and Figure 2As depicted, the reaction vessel 250 can be directly connected to the external riser section 232. In one embodiment, the reaction vessel 250 may include a reaction vessel body section 256 and a reaction vessel transition section 258 positioned between the reaction vessel body section 256 and the external riser section 232. The reaction vessel body section 256 may typically include a larger diameter than the reaction vessel transition section 258, and the reaction vessel transition section 258 tapers from the diameter of the reaction vessel body section 256 to the diameter of the riser 230, such that the reaction vessel transition section 258 protrudes inward from the reaction vessel body section 256 to the external riser section 232. It should be understood that, as used herein, the diameter of a portion of a system unit refers to its overall width, such as... Figure 1 As shown in the horizontal direction.

[0041] Additionally, the reaction vessel body section 256 typically includes a height, which is measured from the particulate solid inlet port 152 to the reaction vessel transition section 258. In one or more embodiments, the diameter of the reaction vessel body section 256 may be greater than its height. In one or more embodiments, the diameter-to-height ratio of the reaction vessel body section 256 may be from 5:1 to 1:5. For example, the diameter-to-height ratio of the main body section 356 of the particulate solids handling container can be 5:1 to 1:5, 4:1 to 1:5, 3:1 to 1:5, 2:1 to 1:5, 1:1 to 1:5, 1:2 to 1:5, 1:3 to 1:5, 1:4 to 1:5, 5:1 to 1:4, 5:1 to 1:3, 5:1 to 1:2, 5:1 to 1:1, 5:1 to 2:1, 5:1 to 3:1, 5:1 to 4:1, or any combination or sub-combination of these ranges.

[0042] In one or more embodiments, the reaction vessel 250 may have at least three times the maximum cross-sectional area of ​​the riser 230. For example, the reaction vessel 250 may have at least three, at least four, at least five, at least six, at least seven, at least eight, at least nine, or even at least ten times the maximum cross-sectional area of ​​the riser 230. As stated herein, unless otherwise expressly stated, “cross-sectional area” refers to the area of ​​a portion of a system component across a cross-section in a plane substantially orthogonal to the overall flow direction of the reactants and / or products.

[0043] In one or more embodiments, based on shape, size, and other processing conditions, such as temperature and pressure in the reaction vessel 250 and riser 230, the reaction vessel 250 may operate in an isothermal or near-isothermal manner, such as in a fast fluidized, turbulent, or bubbling bed reactor, while the riser 230 may operate in a more piston-flow manner, such as in a dilute-phase riser reactor. For example, the reaction vessel 250 may operate as a fast fluidized, turbulent, or bubbling bed reactor, and the riser 230 may operate as a dilute-phase riser reactor, resulting in simultaneous upward movement of the average catalyst and gas flow. As used herein, the term "average flow" refers to net flow, i.e., total upward flow minus reverse or counterflow, which is typically the behavior of fluidized particles. As described herein, a "fast fluidized" reactor may refer to a reactor utilizing a fluidization scheme in which the apparent velocity of the gas phase is greater than the choke velocity and can be semi-dense in operation. As described herein, a "turbulent" reactor may refer to a fluidization scheme in which the apparent velocity is less than the choke velocity and is denser than a fast fluidized scheme. As described herein, a “bubbling bed” reactor can refer to a fluidized process in which well-defined bubbles exist in two distinct phases within a high-density bed. “Choke velocity” refers to the minimum velocity required to maintain a solid in dilute phase mode within a vertical delivery line. As described herein, a “dilute riser” can refer to a riser reactor operating at delivery velocities where the gas and catalyst have approximately the same velocity in the dilute phase.

[0044] In one or more embodiments, the pressure range within reaction vessel 250 can be from 6.0 psia to 100 psia (approximately 41.4 kPa to approximately 689.4 kPa), but in some embodiments, a narrower selection range may be used, such as 15.0 psia to 35.0 psia (approximately 103.4 kPa to approximately 241.3 kPa). For example, the pressure can be from 15.0 psia to 30.0 psia (approximately 103.4 kPa to approximately 206.8 kPa), 17.0 psia to 28.0 psia (approximately 117.2 kPa to approximately 193.1 kPa), or 19.0 psia to 25.0 psia (approximately 131.0 kPa to approximately 172.4 kPa). Unit conversions from standard (non-SI) to measurement (SI) expressions herein include “approximately” to indicate rounding that may occur in measurement (SI) expressions due to the conversion.

[0045] In another embodiment, the weight time space velocity (WHSV) used in the disclosed method can range from 0.1 lb to 100 lb of chemical feed per hour per lb of catalyst (lb feed / h / lb catalyst). For example, in the case where the reactor comprises a reaction vessel 250 operating as a fast fluidized, turbulent, or bubbling bed reactor and a riser 230 operating as a riser reactor, the apparent gas velocity can range from 2 ft / s (about 0.61 m / s) to 80 ft / s (about 24.38 m / s) in the reaction vessel 250, such as 2 ft / s (about 0.61 m / s) to 10 ft / s (about 3.05 m / s), and from 30 ft / s (about 9.14 m / s) to 70 ft / s (about 21.31 m / s) in the riser 230. In another embodiment, a reactor configuration that is entirely of the riser type can operate at a single high apparent gas velocity, for example, in some embodiments, the entire process is at least 30 ft / s (about 9.15 m / s).

[0046] In another embodiment, the ratio of catalyst to feed stream in reaction vessel 250 and riser 230 can be in the range of 5 to 100, based on a weight ratio (w / w). In some embodiments, the ratio can be in the range of 10 to 40, such as 12 to 36 or 12 to 24.

[0047] In another embodiment, the catalyst flux in reaction vessel 250 can be 1 pound per square foot-second (lb / ft). 2 -s)(approximately 4.89 kg / m 2 -s) up to 30lb / ft 2 -s (to approximately 146.5 kg / m²-s), and the catalyst flux in riser 230 can be 10 lb / ft 2 -s (approximately 48.9 kg / m²-s) to 250 lb / ft 2 -s (approximately 1221 kg / m²-s).

[0048] Still referencing Figure 1Reactor section 200 may include a riser 230 for conveying reactants, products, and / or particulate solids from reaction vessel 250 to particulate solids separation section 210. In one or more embodiments, the riser 230 may be generally cylindrical (i.e., having a substantially circular cross-sectional shape), or alternatively may be non-cylindrical, such as a prism shape having a triangular, rectangular, pentagonal, hexagonal, octagonal, elliptical, or other polygonal, or curved closed, or combinations thereof cross-sectional shape. As used throughout this disclosure, the riser 230 typically includes a metal frame and may additionally include a refractory lining or other materials for protecting the metal frame and / or controlling process conditions.

[0049] According to some implementation schemes, the riser 230 may include an outer riser segment 232 and an inner riser segment 234. As used herein, an "outer riser segment" refers to the portion of the riser outside the particulate solids separation section, and an "inner riser segment" refers to the portion of the riser inside the particulate solids separation section. For example, in Figure 1 In the described embodiment, the internal riser section 234 of the reactor section 200 can be located within the particulate solids separation section 210, while the external riser section 232 is located outside the particulate solids separation section 210.

[0050] refer to Figure 1 and Figure 3 The particulate solids separation section 210 may include a housing 212, which defines an internal region 214 of the particulate solids separation section 210. The housing 212 may include a gas outlet port 216, a riser port 218, and a particulate solids outlet port 222. Furthermore, the housing 212 can accommodate the gas / solids separation device 220 and the particulate solids collection area 280 within the internal region 214 of the particulate solids separation section 210.

[0051] In one or more embodiments, the outer shell 212 of the particulate solids separation section 210 may define an upper section 276, an intermediate section 274, and a lower section 272 of the particulate solids separation section 210. Typically, the upper section 276 may have a substantially constant cross-sectional area, such that the cross-sectional area variation in the upper section 276 does not exceed 20%. In one or more embodiments, the cross-sectional area of ​​the upper section 276 may be at least three times the maximum cross-sectional area of ​​the riser tube 230. For example, the cross-sectional area of ​​the upper section 276 may be at least 3 times, at least 4 times, at least 5 times, at least 6 times, at least 7 times, at least 8 times, at least 9 times, at least 10 times, at least 12 times, at least 15 times, or even at least 20 times the maximum cross-sectional area of ​​the riser tube 230. In another embodiment, the maximum cross-sectional area of ​​the upper section 276 may be 5 to 40 times the maximum cross-sectional area of ​​the riser tube 230. For example, the maximum cross-sectional area of ​​the upper segment 276 can be 5 to 40 times, 10 to 40 times, 15 to 40 times, 20 to 40 times, 25 to 40 times, 30 to 40 times, 35 to 40 times, 5 to 35 times, 5 to 30 times, 5 to 25 times, 5 to 20 times, 5 to 15 times, or even 5 to 10 times the maximum cross-sectional area of ​​the riser 230.

[0052] Additionally, in one or more embodiments, the lower segment 272 of the particulate solids separation section 210 may have a substantially constant cross-sectional area, such that the cross-sectional area variation in the lower segment 272 does not exceed 20%. The cross-sectional area of ​​the lower segment 272 may be greater than the maximum cross-sectional area of ​​the riser 230 and less than the maximum cross-sectional area of ​​the upper segment 276. The intermediate segment 274 may be shaped as a frustum, wherein the cross-sectional area of ​​the intermediate segment 274 is not constant, and the cross-sectional area of ​​the intermediate segment 274 transitions from the cross-sectional area of ​​the upper segment 276 to the cross-sectional area of ​​the lower segment 272 throughout the intermediate segment 274.

[0053] Refer again Figure 3 The particulate solids separation section 210 may include a central vertical axis 299. This central vertical axis may extend through the top and bottom of the particulate solids separation section 210, such that it passes through the upper segment 276, the middle segment 274, and the lower segment 272 of the particulate solids separation section 210. In one or more embodiments, the upper segment 276, the middle segment 274, and the lower segment 272 of the particulate solids separation section 210 may be centered on the central vertical axis 299. For example, in an embodiment where the upper segment 276 and the lower segment 272 are substantially cylindrical, the central vertical axis 299 may pass through the midpoint of the diameter of the upper segment 276 and the midpoint of the diameter of the lower segment 272.

[0054] like Figure 1 and Figure 3As depicted, the internal riser segment 234 of the riser 230 may extend through the riser port 218 of the particulate solids separation section 210. The riser port 218 may be any opening in the housing 212 of the particulate solids separation section 210 through which at least the internal riser segment 234 of the riser 230 protrudes into the internal region 214 of the particulate solids separation section 210. In one or more embodiments, the riser port 218 is not located on the central vertical axis 299 of the particulate solids separation section 210. In such embodiments, the riser port 218 may be located on the sidewall of the housing 212 such that the riser port 218 is neither located on the central vertical axis 299 nor oriented such that the riser 230 extends into the particulate solids separation section 210 in a direction substantially parallel to the central vertical axis 299.

[0055] In one or more embodiments, the internal riser segment 234 enters the particulate solids separation section 210 within an intermediate segment 274. In such embodiments, the internal riser segment 234 passes through at least a portion of the intermediate segment 274 and at least a portion of the upper segment 276. In such embodiments, the internal riser segment 234 does not pass through the lower segment 272 of the particulate solids separation section 210. In another embodiment, the internal riser segment 234 may enter the particulate solids separation section 210 within the upper segment 276, and the internal riser segment 234 may pass through at least a portion of the upper segment 276. In such embodiments, the internal riser segment 234 does not pass through the lower segment 272 or the intermediate segment 274.

[0056] Now for reference Figure 3 The internal riser segment 234 may include a vertical portion 296, a non-vertical portion 294, and a non-linear portion 295. As described herein, a "non-linear portion" may refer to a portion of the riser segment that includes a curve or a mitered joint. The non-linear portion 295 may be positioned between the vertical portion 296 and the non-vertical portion 294, and may connect the vertical portion 296 and the non-vertical portion 294. Additionally, the non-vertical portion 294 of the internal riser segment 234 may be located near the riser port 218. In one or more embodiments, the non-vertical portion 294 of the internal riser segment 234 may be adjacent to or directly connected to the riser port 218. Therefore, the riser 230 may extend through the riser port 218 in a non-vertical direction.

[0057] Refer again Figure 2The external riser segment 232 may include a vertical portion 291, a non-vertical portion 293, and a non-linear portion 292. The non-linear portion 292 may be positioned between the vertical portion 291 and the non-vertical portion 293, and may connect the vertical portion 291 and the non-vertical portion 293. The non-vertical portion 293 of the external riser segment 232 may be located near the riser port 218. In one or more embodiments, the non-vertical portion 293 of the external riser segment 232 may be adjacent to or directly connected to the riser port 218. Furthermore, the vertical portion 291 of the external riser segment 232 may be located near the reaction vessel 250. In such embodiments, the expansion joint 282, which is further described in detail herein, may be positioned between the vertical portion 291 of the external riser segment 232 and the reaction vessel 250.

[0058] In one or more embodiments, the riser 230 may extend diagonally through the riser port 218, wherein the diagonal direction is at an angle of 15 to 75 degrees to the vertical plane. For example, the diagonal direction may be at an angle of 15 to 75 degrees to the vertical plane, 20 to 75 degrees to the vertical plane, 25 to 75 degrees to the vertical plane, 30 to 75 degrees to the vertical plane, 35 to 75 degrees to the vertical plane, 40 to 75 degrees to the vertical plane, 45 to 75 degrees to the vertical plane, 50 to 75 degrees to the vertical plane, 55 to 75 degrees to the vertical plane, 60 to 75 degrees to the vertical plane, 65 to 75 degrees to the vertical plane, or 70 to 75 degrees to the vertical plane. 75 degrees, 15 to 70 degrees from the vertical plane, 15 to 65 degrees from the vertical plane, 15 to 60 degrees from the vertical plane, 15 to 55 degrees from the vertical plane, 15 to 50 degrees from the vertical plane, 15 to 45 degrees from the vertical plane, 15 to 40 degrees from the vertical plane, 15 to 35 degrees from the vertical plane, 15 to 30 degrees from the vertical plane, 15 to 25 degrees from the vertical plane, 15 to 20 degrees from the vertical plane, or any combination or sub-combination of these ranges. In one or more alternative embodiments, the riser 230 may extend through the riser port 218 in a substantially horizontal direction. As described herein, a “substantially horizontal” direction may be within 15 degrees, 10 degrees, or even 5 degrees of horizontal.

[0059] Unbound by theory, it is believed that when riser port 218 is not located on the central vertical axis 299 and riser 230 enters the particulate solids separation section 210 in a non-vertical manner, reaction vessel 250 can be positioned closer to gas / solids separation device 220. Therefore, gases and particulate solids will travel a shorter distance in riser 230, thereby reducing the chance of side reactions occurring within riser 230. Such side reactions are likely undesirable because they can lead to reduced yields of light olefins.

[0060] Refer again Figure 3 In the upper section 276 of the particulate solids separation section 210, the internal riser section 234 can be in fluid communication with the gas / solids separation device 220. For example, the vertical portion 296 of the internal riser section 234 can be directly connected to the gas / solids separation device 220. The gas / solids separation device 220 can be any mechanical or chemical separation device operable to separate particulate solids from the gas or liquid phase, such as a cyclone separator or multiple cyclone separators.

[0061] According to one or more embodiments, the gas / solid separation device 220 may be a cyclone separation system that may include two or more stages of cyclone separation. In embodiments where the gas / solid separation device 220 includes more than one cyclone separation stage, the first separation device into which the fluidized stream enters is referred to as the primary cyclone separator. The fluidized stream effluent from the primary cyclone separator may enter a secondary cyclone separator for further separation. The primary cyclone separator may include, for example, a primary cyclone separator and systems commercially available under the names VSS (available from UOP), LD2 (available from Stone and Webster), and RS2 (available from Stone and Webster). Primary cyclone separators are described, for example, in U.S. Patent Nos. 4,579,716, 5,190,650, and 5,275,641, each of which is incorporated herein by reference in its entirety. In some separation systems that utilize a primary cyclone separator as the primary cyclone separation unit, one or more additional cyclone separators, such as secondary and tertiary cyclone separators, are used to further separate particulate solids from the product gas. It should be understood that any primary cyclone separation unit can be used in the embodiments disclosed herein.

[0062] Particulate solids can move upwards from the reaction vessel 250 via riser 230 and into the gas / solid separator 220. The gas / solid separator 220 can be operable to deposit the separated particulate solids into the bottom of the upper section 276 of the particulate solids separation section 210, or into the middle section 274 or the lower section 272. Separated vapors can be removed from the fluid catalytic reactor system 100 via pipe 120 at the gas outlet port 216 of the particulate solids separation section 210.

[0063] Now for reference Figure 1 and Figure 3The lower section 272 of the particulate solids separation section 210 may include a particulate solids collection region 280. In one or more embodiments, the particulate solids collection region 280 may allow particulate solids to accumulate within the particulate solids separation section 210. The particulate solids collection region 280 may include a stripping section. The stripping section may be used to remove product vapors from the particulate solids before they are fed to the regeneration section 300. Since the product vapors fed to the regeneration section 300 will be combusted, it is desirable to remove those product vapors using a stripping tower that utilizes a gas that is cheaper than the product gas.

[0064] The particulate solids collection region 280 in the lower section 272 may include a particulate solids outlet port 222. In one or more embodiments, the particulate solids outlet port 222 may be located near or even on the central vertical axis 299. According to one or more embodiments, the bottom of the particulate solids collection region 280 may be curved such that the particulate solids outlet port 222 is located at the lowest part of the particulate solids collection region 280. A riser 126 may be connected to the particulate solids separation section 210 at the particulate solids outlet port 222, and particulate solids may be transferred out of the reactor section 200 and into the regeneration section 300 via the riser 126. Optionally, the particulate solids may also be transferred directly back into the reaction vessel 250 via the riser 122. In such embodiments, the risers 122 and 126 may each be offset from the central vertical axis 229. Alternatively, the particulate solids may be premixed with the regenerated particulate solids in the delivery riser 130.

[0065] Without being bound by theory, it is believed that when the riser 230 does not pass through the particulate solids collection region 280 and when the particulate solids outlet port 222 is located on the central vertical axis 299, the flow of particulate solids through the particulate solids collection region 280 can be improved compared to a design where the riser 230 does pass through the particulate solids collection region 280. When the riser 230 does not pass through the particulate solids collection region 280 and the riser port 218 is not located on the central vertical axis 299, the particulate solids outlet port 222 can be located on the central vertical axis 299. Therefore, the particulate solids can move through the particulate solids collection region 280 in a more closely piston-like manner. This may increase the residence time of the particulate solids within the particulate solids collection region 280, which could be beneficial when stripping or other anticipated processes occur within the particulate solids collection region 280.

[0066] As described herein, the components of a system unit, such as the walls of a reaction vessel, separation section, or riser, may comprise metallic materials, such as carbon or stainless steel. Furthermore, the walls of various system units may have portions that are attached to other parts of the same system unit or to another system unit. Sometimes, attachment points or connection points are referred to herein as “attachment points” and may incorporate any known bonding medium, such as, but not limited to, welding, adhesives, solder, etc. It should be understood that components of the system may be “directly connected” at attachment points such as welds.

[0067] To mitigate damage caused by hot particulate solids and gases, refractory materials can be used as linings for various system components. Refractory materials may be included in the riser 230 and the particulate solids separation section 210. It should be understood that while specific refractory material arrangements and materials are provided in the embodiments, these embodiments should not be considered as limitations on the physical structure of the disclosed system. For example, the refractory lining may extend along the inner surface of the riser 230 and along the inner surfaces of the intermediate sections 274 and the upper section 276 of the particulate solids separation section 210. The refractory lining may include hexagonal mesh or other suitable refractory materials.

[0068] The mechanical loads applied to the reaction vessel 250 by the weight of the particulate solids and other parts of the reactor section 200, and more specifically to the connected vessel nozzles such as 218, can be high, and springs can be used to allow vessel movement due to thermal differences in the vessel and pipe walls. When the reaction vessel 250 is empty, these springs can apply upward pressure to the vessel and nozzles 218. When the vessel has an abnormal catalyst weight, the load on the nozzles 218 can be moved downward. This design principle reduces the total load that the nozzles 218 will see in either direction. For example, the reaction vessel 250 can be suspended on springs, or the springs can be positioned below the reaction vessel 250 to support its weight, the catalyst weight, and allow thermal movement. Figure 1 A spring support 188 is depicted at the reaction vessel 250, which is mechanically attached to the reactor section 200, wherein the reactor section 200 is suspended from the support structure by the spring support 188.

[0069] Additionally, the reaction vessel 250 and the riser 230 can experience thermal expansion. Therefore, suspending the reaction vessel 250 on the spring support 188 or supporting the reaction vessel 250 with the spring support 188 can reduce the tension between the reaction vessel 250 and the external riser section 232. Now refer to Figure 2Instead of a spring, expansion joint 282 can be positioned between reaction vessel 250 and external riser section 232. As described herein, "expansion joint" can refer to a bellows made of metal or other suitable materials such as refractory, plastic, fiber, or elastomer that reduces stress between system components joined by the expansion joint. For example, expansion joints can be used to reduce stress between system components caused by thermal expansion and contraction. In one or more embodiments, expansion joint 282 can be used in conjunction with a spring support to alleviate stress caused by thermal expansion between reaction vessel 250 and external riser section 232.

[0070] After separation in particulate solids separation section 210, the used particulate solids are transferred to regeneration section 300. As described herein, regeneration section 300 may share many structural similarities with reactor section 200. Therefore, the reference numerals assigned to these portions of regeneration section 300 are similar to those used with reference to reactor section 200, wherein given portions of reactor section 200 and regeneration section 300 may function similarly and have similar physical structures if the last two digits of the reference numerals are the same. Therefore, much of the disclosure relating to reactor section 200 can also be applied to regeneration section 300, and the differences between reactor section 200 and regeneration section 300 will be emphasized below.

[0071] Now referencing the regeneration section 300, such as Figure 1The depicted particulate solids handling container 350 of the regeneration section 300 may include one or more reactor vessel inlet ports 352 and a reactor vessel outlet port 354 in fluid communication with or even directly connected to an external riser section 332 of the riser section 330. The particulate solids handling container 350 may be in fluid communication with the particulate solids separation section 210 via a riser 126, which may supply used particulate solids from the reactor section 200 to the regeneration section 300 for regeneration. The particulate solids handling container 350 may include additional reactor vessel inlet ports 352, wherein a gas inlet 128 is connected to the particulate solids handling container 350. The gas inlet 128 may supply reactive gases, such as supplemental fuel gases and oxygen-containing gases, including air, which may be used to at least partially regenerate the particulate solids. In one or more embodiments, the particulate solids handling container 350 may include a plurality of additional reactor vessel inlet ports, and each additional reactor vessel inlet port may supply a different reactive fluid to the particulate solids handling container 350. For example, the particulate solids can coke after reacting in the reaction vessel 250, and the coke can be removed from the particulate solids through a combustion reaction. For example, an oxygen-containing gas, such as air, can be fed into the particulate solids processing vessel 350 through the gas inlet 128 to oxidize the particulate solids, or supplementary fuel can be fed into the particulate solids processing vessel 350 and burned to heat the particulate solids.

[0072] like Figure 1 As depicted, the particulate solids handling container 350 can be directly connected to the outer riser section 332 of the riser 330. In one embodiment, the particulate solids handling container 350 may include a particulate solids handling container body section 356 and a particulate solids handling container transition section 358. The particulate solids handling container body section 356 typically includes a larger diameter than the particulate solids handling container transition section 358, and the particulate solids handling container transition section 358 tapers from the diameter of the particulate solids handling container body section 356 to the diameter of the outer riser section 332, such that the particulate solids handling container transition section 358 protrudes inward from the particulate solids handling container body section 356 to the outer riser section 332.

[0073] It should be understood that the particulate solids processing container 350 and the riser 330 can undergo thermal expansion and, as described above, can be supported by the spring support 188. Additionally, in one or more embodiments, the particulate solids processing container 350 can be engaged with the riser 330 via an expansion joint. For example, the expansion joint can be positioned between the particulate solids processing container 350 and the external riser segment 332.

[0074] Still referencing Figure 1 The particulate solids separation section 310 includes a housing 312 that defines an internal region 314 of the particulate solids separation section 310. The housing 312 may include a gas outlet port 316, a riser port 318, and a particulate solids outlet port 322. Furthermore, the housing 312 can accommodate the gas / solids separation device 320 and the solid particle collection area 380 within the internal region 314 of the particulate solids separation section 310.

[0075] As described above regarding the particulate solids separation section 210, similar to reactor section 200, the outer shell 312 of the particulate solids separation section 310 may define the upper section 376, the middle section 374, and the lower section 372 of the particulate solids separation section 310.

[0076] Refer again Figure 1 The riser 330 extends via riser port 318 into the inner region 314 of the regeneration section 300. In one or more embodiments, the riser 330 may extend through the riser port 318 in a non-vertical direction. In one or more embodiments, the inner riser segment 334 does not pass through the lower segment 372 of the particulate solids separation section 310.

[0077] refer to Figure 1 The housing 312 may also accommodate a riser termination device 378. The riser termination device may be located near the internal riser segment 334. Gas and particulate solids passing through the riser 330 may be at least partially separated by the riser termination device 378. The gas and remaining particulate solids may be conveyed to a secondary separation device 320 in the particulate solids separation section 310. The secondary separation device 320 may be any device suitable for separating solid particles from the gas, such as a cyclone separator or a series of cyclone separators, as described above with respect to the gas / solid separation device 220. The secondary separation device 320 may deposit the separated particulate solids into the bottom of the upper segment 376, the middle segment 374, or the lower segment 372 of the particulate solids separation section 310. Thus, the particulate solids may flow from the bottom of the upper segment 376 or the middle segment 374 to the lower segment 372 by gravity.

[0078] The lower segment 372 of the particulate solids separation section 310 may include a solid particle collection region 380, which allows particulate solids to accumulate in the lower segment 372. In one or more embodiments, the solid particle collection region 380 may include one or more of an oxygen soaking region, an oxygen stripping region, and a reduction region. The solid particle collection region 380 may also include a particulate solids outlet port 322, similar to the particulate solids outlet port 222 described above.

[0079] In one or more embodiments, the riser 124 may be in fluid communication with the particulate solids outlet port 322, and the regenerated particulate solids may be conveyed from the regeneration section 300 to the reactor section 200 through the riser 124. Thus, the particulate solids can be continuously recycled through the reactor system 100.

[0080] Example

[0081] The following examples illustrate the features of this disclosure, but are not intended to limit the scope of this disclosure. The following examples discuss the performance of a solid particle collection region according to one or more embodiments disclosed herein.

[0082] Example 1: Riser residence time and propylene selectivity

[0083] The reactor system according to the disclosed implementation scheme was modeled to analyze the effect of residence time in the riser on propylene selectivity during propane dehydrogenation. The modeling results comparing changes in riser residence time with changes in propylene selectivity are shown in Table 1.

[0084] Table 1 .

[0085] -0.51 0.31 -0.76 0.44 -1.27 0.75

[0086] As shown in Table 1, propylene selectivity increases with decreasing residence time in the riser. This is likely due to a reduction in the number of side reactions that may occur in the riser. When the residence time in the riser is reduced, these side reactions have fewer opportunities to occur, which in turn leads to an overall improvement in the propylene selectivity of the system. As mentioned above, using a riser that enters the particulate solids separation section in a non-vertical orientation allows for a shorter riser. Therefore, the riser disclosed in this invention provides advantages over conventional risers that enter the particulate solids separation section vertically through the bottom of the section by having a shorter length and thus a shorter residence time (during which undesirable side reactions may occur).

[0087] Example 2: Flow of particulate solids through a particulate solids collection area

[0088] The flow of particulate solids through two particulate solid collection regions is modeled. The first particulate solid collection region 410 is depicted in... Figure 4 The first particulate solids collection area 410 includes a single outlet riser 420 located at the bottom of the annular shape. The outlet riser 420 is not positioned on the central axis 430 of the first particulate solids collection area 410. The first particulate solids collection area 410 also includes several cable beam supports covered by a subway grille 440.

[0089] The second particulate solid collection area 510 is depicted in Figure 5 The second particulate solids collection area 510 includes a cylindrical outlet riser 520 located at the bottom of the particulate solids collection area 510. The outlet riser 520 is positioned on the central axis 530 of the second particulate solids collection area 510. The second particulate solids collection area 510 also includes several cable beam supports covered by a subway grille 540.

[0090] Computational fluid dynamics (CFD) simulations were performed to model the flow of particulate solids through a first and a second particulate solids collection region. The solids residence time distribution (RTD) was thus obtained in each container. For simulation purposes, the diameter of each particulate solids collection region in the first and second regions was set to 46 inches. The apparent gas velocity at the bottom of each container was 0.3 ft / sec, and the average particulate solids flux was 3.4 lb / ft. 2 -sec. Additionally, the average turnaround time for granular solids is 8 minutes.

[0091] CFD simulations of the first particulate solids collection area predict a minimum residence time of approximately 30 seconds for particulate solids due to short-circuiting on the outlet riser side of the container. The CFD simulations also predict that approximately 42% of the particulate solids will have a residence time of less than 4 minutes. CFD simulations of the second particulate solids collection area predict a minimum residence time of more than 1 minute for particulate solids, with only 30% of the particulate solids having a residence time of less than 4 minutes.

[0092] The RTDs of the first and second particulate solids collection regions are graphically depicted in... Figure 6 The RTD of the first particulate solids collection zone is depicted by line 610, and the RTD of the second particulate solids collection zone is depicted by line 620. Additionally, the RTDs of one continuous stirred tank reactor (CSTR) and three CSTRs in series are shown in the diagram. Figure 6 For reference only. The RTD of a single CSTR is depicted by line 630, and the RTD of three cascaded CSTRs is depicted by line 640. (See also...) Figure 6 As shown, the RTD of the first particulate solids collection region is comparable to that of a single CSTR, and the RTD of the second particulate solids collection region is comparable to that of three CSTRs in series. The second particulate solids collection region offers advantages over the first because the flow of particulate solids through the second particulate solids collection region more closely resembles a piston flow. Therefore, less particulate solids leave the particulate solids collection region rapidly, and less particulate solids remain in the particulate solids collection region for a longer period. This results in more consistent processing of particulate solids within the particulate solids collection region.

[0093] In a first aspect of this disclosure, olefins can be produced by a method comprising contacting a hydrocarbon feed stream with particulate solids in a reaction vessel. Contacting the hydrocarbon feed stream with the particulate solids causes the hydrocarbon feed stream to react to form an olefin-containing product stream. The reaction vessel may be connected to a riser, and the reaction vessel may have a maximum cross-sectional area at least three times the maximum cross-sectional area of ​​the riser. The method may further comprise conveying the particulate solids through the riser. The riser may extend through a riser port of a shell of a particulate solids separation section, such that the riser may include an inner riser segment located in an inner region of the particulate solids separation section and an outer riser segment located outside the shell of the particulate solids separation section. The particulate solids separation section may include at least a shell defining an inner region of the particulate solids separation section. The shell may include a gas outlet port, a riser port, and a particulate solids outlet port. The shell may house a gas / solid separation device and a solid particle collection area within the inner region of the particulate solids separation section. The riser port can be positioned on the side wall of the housing such that it is not located on the central vertical axis of the particulate solids separation section. The method may further include separating the particulate solids from the olefin-containing product stream in the gas / solid separation device, and conveying the separated particulate solids to a solid particle collection area located near the central vertical axis of the particulate solids separation section.

[0094] The second aspect of this disclosure may include the first aspect, wherein the riser extends through the riser port in a non-vertical direction.

[0095] The third aspect of this disclosure may include either the first aspect or the second aspect, wherein the lift tube extends diagonally through the lift tube port, wherein the diagonal direction is at an angle of 15 to 75 degrees to the vertical plane.

[0096] The fourth aspect of this disclosure may include any one of the first to the second aspects, wherein the riser extends through the riser port in a substantially horizontal direction.

[0097] The fifth aspect of this disclosure may include any one of the first to fourth aspects, wherein the internal riser segment includes a vertical portion, a non-vertical portion located near the riser port, and a non-linear portion connecting the vertical portion and the non-vertical portion.

[0098] The sixth aspect of this disclosure may include any one of the first to fifth aspects, wherein the external riser segment includes a vertical portion located near the reaction vessel, a non-vertical portion located near the riser port, and a non-linear portion connecting the vertical portion and the non-vertical portion.

[0099] The seventh aspect of this disclosure may include any one of the first to sixth aspects, wherein the reaction vessel operates as a fast fluidized, turbulent, or bubbling bed reactor, and the riser operates as a dilute phase riser reactor.

[0100] The eighth aspect of this disclosure may include any one of the first to the seventh aspects, wherein the maximum cross-sectional area of ​​the outer shell of the upper particulate solid separation section is 5 to 40 times the maximum cross-sectional area of ​​the riser.

[0101] The ninth aspect of this disclosure may include any one of the first to eighth aspects, wherein the reaction vessel includes a reaction vessel body section and a reaction vessel transition section, wherein the reaction vessel transition section is located between the reaction vessel body section and the external riser section.

[0102] The tenth aspect of this disclosure may include the ninth aspect, wherein the reaction vessel body section has a diameter and a height, wherein the ratio of the diameter to the height of the reaction vessel body section is 5:1 to 1:5.

[0103] The eleventh aspect of this disclosure may include any one of the first to tenth aspects, wherein the reaction vessel is supported by a spring support.

[0104] The twelfth aspect of this disclosure may include any one of the first to eleventh aspects, wherein the reaction vessel is connected to the vertical portion of the external riser section via an expansion joint.

[0105] The thirteenth aspect of this disclosure may include any one of the first to twelfth aspects, wherein the gas / solid separation device includes one or more cyclone separators.

[0106] The fourteenth aspect of this disclosure may include any one of the first to thirteenth aspects, wherein the riser does not pass through the solid particle collection area.

[0107] The fifteenth aspect of this disclosure may include any one of the first to fourteenth aspects, wherein the solid particle collection area includes a stripping tower.

[0108] The subject matter of this disclosure has been described in detail and with reference to specific embodiments. It should be understood that any detailed description of a component or feature of an embodiment does not necessarily imply that such component or feature is necessary for a particular embodiment or any other embodiment. Furthermore, it will be apparent to those skilled in the art that various modifications and changes can be made to the described embodiments without departing from the spirit and scope of the claimed subject matter.

[0109] For purposes of description and limitation of this disclosure, it should be noted that the terms “about” or “approximately” are used in this disclosure to indicate the degree of uncertainty attributable to any quantitative comparison, value, measurement or other representation. The terms “about” and / or “approximately” are also used in this disclosure to indicate the degree to which a quantitative representation may vary from a specified reference without causing a fundamental change in the subject matter of interest.

[0110] It should be noted that one or more of the appended claims use the term "wherein" as a transitional expression. For the purpose of defining this technology, it should be noted that this term is introduced in the claims as an open transitional phrase used to introduce a description of a series of features of the structure, and should be interpreted in a similar manner to the more commonly used open prepositional term "comprising".

[0111] It should be understood that when the first component is described as "containing" the second component, it is anticipated in some embodiments that the first component is "composed of" or "substantially composed of" the second component. It should also be understood that when the first component is described as "containing" the second component, it is anticipated in some embodiments that the first component may contain at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or even at least 99% of the second component (wherein the percentage may be weight percentage or molar percentage).

[0112] Furthermore, the term "substantially composed of" is used in this disclosure to refer to a quantitative value that does not materially affect the essential and novel characteristics of this disclosure. For example, a chemical composition "substantially" composed of a particular chemical component or group of chemical components should be understood to mean that the composition contains at least about 99.5% of that particular chemical component or group of chemical components.

[0113] It should be understood that any two quantitative values ​​assigned to a certain characteristic can constitute a range for that characteristic, and all combinations of ranges formed by all said quantitative values ​​of a given characteristic are considered in this disclosure. It should be understood that in some embodiments, the compositional range of a chemical component in the composition should be understood as a mixture containing isomers of that component. In other embodiments, the chemical compound may be present in alternative forms, such as derivatives, salts, hydroxides, etc.

Claims

1. A method for producing olefins, the method comprising: A hydrocarbon feed stream is contacted with particulate solids in a reaction vessel, the contact of the hydrocarbon feed stream with the particulate solids causing the hydrocarbon feed stream to react to form an olefin-containing product stream, wherein the reaction vessel is connected to a riser, wherein the reaction vessel has a maximum cross-sectional area of ​​at least 3 times the maximum cross-sectional area of ​​the riser, and wherein the reaction vessel operates as a fast fluidized, turbulent, or bubbling bed reactor, and the riser operates as a dilute phase riser reactor. The particulate solids are conveyed through the riser tube, which extends through a riser tube port of the housing of the particulate solids separation section, such that the riser tube includes an inner riser tube segment located in the inner region of the particulate solids separation section and an outer riser tube segment located outside the housing of the particulate solids separation section, wherein the particulate solids separation section includes at least the housing defining the inner region of the particulate solids separation section, the housing including a gas outlet port, a riser tube port, and a particulate solids outlet port, and wherein the housing houses a gas / solid separation device and a solid particle collection area in the inner region of the particulate solids separation section, and wherein the riser tube port is located on a sidewall of the housing such that the riser tube port is not located on the central vertical axis of the particulate solids separation section, and the riser tube port is neither located on the central vertical axis nor oriented such that the portion of the riser tube extending from the riser tube port to the particulate solids separation section is in a direction substantially parallel to the central vertical axis; The particulate solids are separated from the olefin-containing product stream in the gas / solid separation device; and The particulate solids separated from the olefin-containing product stream are conveyed to the solid particle collection area located near the central vertical axis of the particulate solids separation section.

2. The method of claim 1, wherein the riser extends through the riser port in a non-vertical direction.

3. The method according to claim 1 or 2, wherein the lifting tube extends through the lifting tube port in a diagonal direction, wherein the diagonal direction is at an angle of 15 degrees to 75 degrees with the vertical plane.

4. The method according to claim 1 or claim 2, wherein the riser extends through the riser port in a substantially horizontal direction.

5. The method according to claim 1 or 2, wherein the internal riser segment comprises a vertical portion, a non-vertical portion located near the riser port, and a non-linear portion connecting the vertical portion and the non-vertical portion.

6. The method according to claim 1 or 2, wherein the external riser segment comprises a vertical portion located near the reaction vessel, a non-vertical portion located near the riser port, and a non-linear portion connecting the vertical portion and the non-vertical portion.

7. The method according to claim 1 or 2, wherein the maximum cross-sectional area of ​​the outer shell of the upper particulate solids separation section is 5 to 40 times the maximum cross-sectional area of ​​the riser.

8. The method according to claim 1 or 2, wherein the reaction vessel includes a reaction vessel body section and a reaction vessel transition section, wherein the reaction vessel transition section is located between the reaction vessel body section and the external riser section.

9. The method of claim 8, wherein the reaction vessel body section has a diameter and a height, wherein the ratio of the diameter to the height of the reaction vessel body section is 5:1 to 1:

5.

10. The method according to claim 1 or 2, wherein the reaction vessel is supported by a spring support.

11. The method according to claim 1 or 2, wherein the reaction vessel is connected to the vertical portion of the external riser section via an expansion joint.

12. The method according to claim 1 or 2, wherein the gas / solid separation device comprises one or more cyclone separators.

13. The method according to claim 1 or 2, wherein the lifting tube does not pass through the solid particle collection area.

14. The method according to claim 1 or 2, wherein the solid particle collection area comprises a stripping tower.

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