RU2778322C1 - Bimodal reactor with radial flow - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: bimodal reactor with radial flow is proposed, containing a cylindrical outer casing surrounding at least five cylindrical concentric zones, including at least three annular steam zones, including an outer annular steam zone, a middle annular steam zone and a central annular steam zone. At least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, wherein the outer catalyst zone is located between the outer annular steam zone and the middle annular steam zone, and the inner catalyst zone is located between the middle annular steam zone and the central annular steam zone. A distribution pipeline, made with the possibility of vertically injecting raw materials into the lower end of each of one or two of at least three annular steam zones and diverting the product from the lower end of each of one or two remaining of at least three annular steam zones.

EFFECT: improving the use of the catalyst, minimizing downtime and/or coking.

35 cl, 14 dwg

Description

FEDERALLY FUNDED RESEARCH OR DEVELOPMENT STATEMENT

[0001] Not applicable.

LINK TO MICROFISH

[0002] Not applicable.

FIELD OF TECHNOLOGY

[0003] The disclosed devices, systems and methods relate to radial flow reactors. More specifically, the disclosed devices, systems and methods relate to bimodal radial flow reactors. Even more specifically, the disclosed devices, systems and methods relate to bimodal radial flow reactors containing at least three annular steam zones and at least two catalyst zones.

BACKGROUND OF THE INVENTION

[0004] The radial reactor comprises a cylindrical reactor vessel containing specially adapted reactor internals. The main reactor internals that provide the radial flow pattern in a conventional fixed bed radial flow reactor are the inlet barrier (disk plates), the inlet manifold and the axial outlet manifold. The two main types of inlet distributors include wedge metal screens and a series of undulations, each undulation being a relatively small diameter perforated semi-cylinder located around the circumference of the vessel. The axial exhaust manifold may be in the form of a perforated cylinder or "centre tube". The catalyst is usually loaded into the annulus located between the inlet manifold and the center pipe, and the top of the catalyst bed is covered with an overlay plate.

[0005] Depending on the axial direction of flow in the distribution channel and the central tube, radial flow reactors can be classified as z-flow or π-flow type reactors. Depending on the radial direction of flow in the reactor, radial flow reactors can also be classified as centripetal (CP) or centrifugal (CF) flow type reactors. In the CP flow type reactor, the gas is fed into the distribution channel and flows radially from the outer sieve to the central tube, while in the CF flow type reactor, the gas is fed into the central tube and flows radially from the central tube to the outer sieve. Thus, four flow configurations are typical for conventional radial flow reactors; they can be classified as CP-z, CP-π, CF-z and CF-π configurations.

[0006] Thus, conventional radial flow reactors comprise a single catalyst bed, wherein the feed gas is introduced into the distribution channel or central tube, and the product is withdrawn in the same or opposite axial direction from the central tube or distribution channel after passing through the single catalyst bed. .

[0007] Radial flow reactors are often used to carry out endothermic reactions. Reforming reactions such as the AROMAX® processes manufactured by Chevron Phillips Chemical Company LP, Wooddens, Texas, are extremely endothermic. As the vaporized feed passes through the catalyst bed in the reactor (for example, from the metal screen or undulations to the center tube), the catalyst temperature can rapidly drop below the activation temperature for dehydrogenation reactions. When the working catalyst is deactivated, the reactor inlet temperature is raised to compensate for the loss of activity. The deactivated catalyst is also a less selective catalyst and has significant activity in hydrocarbon cracking reactions. This deactivated catalyst also has a higher temperature, which also results in more cracking products. Cracked products represent a significantly lower category from the cost of more expensive feedstocks (valued as gasoline blending components) to light hydrocarbons (valued as fuel gas). Cost-effective end-of-cycle is achieved when the amount of light hydrocarbon value loss due to cracking is greater than or equal to the cost of replacing the catalyst and the cost of production losses in the replacement process. In the event that the economic end-of-cycle criterion is reached, most of the catalyst in the vicinity of the steam exit zone is not fully utilized.

[0008] Accordingly, there is a need for improved radial flow reactors, as well as systems and methods that use such reactors. Desirably, such reactors, systems, and methods can improve catalyst utilization, minimize downtime, and/or minimize coking.

SUMMARY OF THE INVENTION

[0009] Disclosed herein is a bimodal radial flow reactor comprising: a cylindrical outer casing surrounding at least five cylindrical concentric zones, including at least three annular vapor zones and at least two catalyst zones, wherein at least two zones of the catalyst contain an outer catalyst zone and an inner catalyst zone, and at least three annular steam zones contain an outer annular steam zone, a middle annular steam zone and a central annular steam zone, and while the outer catalyst zone is located between the outer annular steam zone and the middle an annular vapor zone, wherein the inner catalyst zone is located between the middle annular vapor zone and the central annular vapor zone; as well as a distribution pipeline configured to vertically enter the raw material into the lower end of each of one or two of the at least three annular steam zones and remove the product from the lower end of each of the one or two remaining of the at least three annular steam zones.

[0010] Also disclosed herein is a bimodal radial flow guard bed reactor comprising: a cylindrical outer shell surrounding at least five cylindrical concentric zones including at least two annular vapor zones, at least two catalyst zones, and a separation zone layer, wherein at least two catalyst zones contain an outer catalyst zone and an inner catalyst zone, while at least two annular steam zones contain an outer annular steam zone and a central annular steam zone, and the outer catalyst zone is located between the outer annular steam zone a bed separation zone and a bed separation zone, wherein the inner catalyst zone is located between the bed separation zone and the central annular vapor zone; and a distribution conduit configured to vertically introduce feedstock into the lower end of the outer annular steam zone and withdraw product from the lower end of the central annular steam zone.

[0011] Also disclosed herein is a radial flow bimodal reactor comprising: a cylindrical outer shell surrounding five cylindrical concentric zones including three annular vapor zones and two catalyst zones, the two catalyst zones comprising an outer catalyst zone and an inner catalyst zone, with In this case, the inner catalyst zone and the outer catalyst zone are made in the form of removable baskets for the catalyst, and while the three annular steam zones contain an outer annular steam zone, a middle annular steam zone and a central annular steam zone, and while the outer catalyst zone is located between the outer annular steam zone zone and the middle annular steam zone, and while the inner zone of the catalyst is located between the middle annular steam zone and the Central annular steam zone; as well as a distribution pipeline configured to vertically enter the raw material into the lower end of each of one or two of the three annular steam zones and discharge the product from the lower end of each of the one or two remaining of the three annular steam zones.

[0012] Also disclosed herein is a reactor system comprising a guard bed bimodal radial flow reactor, at least one radial flow bimodal reactor with a removable catalyst basket, and at least one fixed bed bimodal radial flow reactor, wherein a bimodal radial flow reactor with a protective bed is located before at least one bimodal radial flow reactor with a removable catalyst basket, and wherein at least one bimodal radial flow reactor with a removable catalyst basket is located before at least one bimodal reactor with radial flow with fixed bed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In the detailed description, reference will be made to the drawings briefly described below, where like reference numerals refer to like parts, unless otherwise indicated.

[0014] In FIG. 1 illustrates a simplified diagram of a bimodal radial flow reactor according to the present invention;

[0015] In FIG. 2A is a schematic diagram of a bimodal radial flow reactor according to an embodiment of this invention;

[0016] In FIG. 2B illustrates a plan view of the top of the cylindrical outer casing 5 of the fixed bed bi-modal radial flow reactor (BRFR) 10 of FIG. 2A;

[0017] In FIG. 3A is a diagram of a bimodal radial flow reactor according to another embodiment of this invention;

[0018] In FIG. 3B is a plan view of the underside of the lid 130 showing the lid flange 132, the pressure pad 133A, the pressure pad 133B, and the support structure 109A/B;

[0019] In FIG. 3C illustrates a plan view of the top of the cylindrical outer casing 105 of the reactor 110 of FIG. 3A;

[0020] In FIG. 4A is a diagram of an inner catalyst basket 120B', an outer catalyst basket 120A', and a cylindrical outer shell or reactor shell 105' in accordance with embodiments of this invention;

[0021] In FIG. 4B illustrates a plan view of the inner catalyst basket 120B' of FIG. 4A;

[0022] In FIG. 4C illustrates a plan view of the outer catalyst basket 120A of FIG. 4A;

[0023] In FIG. 5A is a diagram of a bimodal radial flow guard bed reactor according to an embodiment of this invention;

[0024] In FIG. 5B illustrates a plan view of the top of the cylindrical outer casing 205 of the reactor 210 of FIG. 5A;

[0025] In FIG. 6 is a schematic plan view of a bimodal radial flow reactor in accordance with embodiments of this invention;

[0026] In FIG. 7 is a diagram of an integrated reactor circuit design comprising a guard bed bimodal radial flow reactor, a removable catalyst basket bimodal radial flow reactor, and a fixed bed bimodal radial flow reactor in accordance with an embodiment of this invention.

[0027] In FIG. 8 is a diagram of an integrated reactor loop design comprising a bimodal guard bed radial flow reactor, three bimodal radial flow reactors with a removable catalyst basket, and three fixed bed bimodal radial flow reactors in accordance with an embodiment of this invention.

DETAILED DESCRIPTION

[0028] With reference to FIG. 1, which illustrates a simplified diagram of a 10/110 bimodal radial flow reactor of this invention (which will be described in detail below with reference to FIGS. 2 and 3), this document discloses a 10/110 bimodal radial flow reactor (BRFR) which contains at least three annular steam zones 15A/115A, 15B/115B and 15C/115C and at least two catalyst zones 20A/120A and 20B/120B, systems containing a bimodal radial flow reactor, as well as methods for using a bimodal reactor with radial flow and systems containing it. The BRFR is designed such that the catalyst volume is divided within a single reactor into two or more separate catalyst zones and interbedded annular vapor zones. The design of the flow channels of a bimodal radial flow reactor may allow improved catalyst utilization, minimize downtime, and/or minimize coking when compared to conventional "unimodal" radial flow reactors. For example, in embodiments of the invention, during the first part of the cycle, the feed may be first introduced into the middle annular steam zone 15V/115V, may first pass through the internal catalyst zone 20V/120V, and exit the reactor 10/110 through the central annular steam zone 15C /115С; during the second part of the cycle, the feed may first be introduced into the middle annular vapor zone 15B/115B, may first pass through the outer zone of the catalyst 20A/120A, and exit the reactor 10/110 through the outer annular vapor zone 15A/115A. Thus, in embodiments of the invention, the system and method disclosed herein can be used to divide the catalyst volume into sections (eg, in half), and each section can be used in different ways. Although reference is made from time to time in the specification to catalysts and reforming/aromatization reactions, it should be understood that the BRFR disclosed herein may be suitable for use with other catalysts and for other reactions.

[0029] In embodiments of the invention, at least two of the catalyst zones in the BRFR comprise removable catalyst baskets. These removable catalyst baskets can be removed from the top of the BRFR. In embodiments of the invention, at least two catalyst zones in a BRFR comprise fixed beds, which in embodiments of the invention may be provided by fixed catalyst baskets or "fixed catalyst baskets". In such embodiments, one or both of the at least two catalyst zones may be provided with one or more orifices fluidly connected to their lower end such that the catalyst can be removed through the orifices.

[0030] The BRFR described herein further comprises a distribution conduit that allows both feedstock to be introduced and product to be withdrawn from the lower end of the BRFR. Because the distribution piping contains both feed and effluent piping from the lower end of the BRFR, less piping is required, and removal of removable catalyst baskets from the upper end of the BRFR is facilitated by BRFR configurations with removable catalyst baskets.

[0031] Also disclosed herein is a bi-modal radial How guard bed reactor (BRFGBR) comprising at least two annular steam zones, at least two catalyst zones, and a bed separation zone. In embodiments of the invention, at least two of the catalyst zones in the BRFGBR comprise removable catalyst baskets. The use of such a bimodal radial flow guard bed reactor can eliminate the need for a higher pressure drop safety reactor or sulfur adsorber, which can reduce capital costs compared to systems without BRFGBR.

[0032] This document also discloses a system containing more than one of the reactors disclosed herein. In embodiments of the invention, the system of this invention comprises at least two reactors selected from the BRFR and BRFGBR disclosed herein. The system of this invention may comprise at least two reactors selected from a removable catalyst basket BRFR, a fixed catalyst basket or fixed catalyst bed BRFR, and a BRFGBR. In embodiments, the system of this invention comprises a BRFGBR, at least one BRFR with a removable catalyst basket, and at least one BRFR with a fixed catalyst basket. In embodiments, the system of this invention comprises a BRFGBR with a removable catalyst basket, three BRFRs with removable catalyst baskets, and three BRFRs with fixed catalyst baskets. In such embodiments, the three BRFRs with removable catalyst baskets may be smaller (ie, have a smaller overall catalyst volume and/or reactor diameter) than BRFRs with fixed catalyst baskets; for design where the desired chemical interactions entail highly endothermic reactions, such as when larger diameter catalyst beds could not be fully utilized due to the rapid reaction temperature drop across the radial beds. Methods for using the reactors and plants disclosed herein are also provided.

[0033] In a unimodal reactor, the process flow path is single direction, while in a bimodal reactor, as described herein, the process flow path may be bidirectional within the same reactor shell. The bimodal reactor allows the process stream to flow simultaneously through multiple beds contained in the same reactor, thus reducing the number of reactor shells required for a given mass or volume of catalyst used; alternatively, the process flow may preferably be increased or decreased through each catalyst bed in the same reactor to improve catalyst utilization. In other words, a unimodal reactor has only one maximum in the cross section of the reactor for heat released in exothermic reactions or for heat absorbed in endothermic reactions. In a bimodal reactor, there may be two or more peaks in the cross section of the reactor for heat released in exothermic reactions or for heat absorbed in endothermic reactions. As used herein, the term "bimodal" when used to describe a radial flow reactor thus means a multiple split-bed, branched-flow, radial-flow reactor that has two different flow paths through the two beds, where the percentage flow rate between the two layers may vary.

[0034] BRFR is disclosed herein. In embodiments of the invention, the radial flow bimodal reactor comprises a cylindrical outer vessel or reactor vessel surrounding at least five cylindrical concentric zones, including at least three annular vapor zones and at least two catalyst zones. At least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, and at least three annular vapor zones comprise an outer annular vapor zone, a middle annular vapor zone, and a central annular vapor zone. The outer catalyst zone is located between the outer annular vapor zone and the middle annular vapor zone, and the inner catalyst zone is located between the middle annular vapor zone and the central annular vapor zone. The BRFR further comprises a distribution pipeline configured to vertically feed the feed into the lower end of each of one or two of the at least three annular steam zones and discharge the product from the lower end of each of the one or two remaining of the at least three annular steam zones. The catalyst zones in the BRFR of this invention may comprise fixed catalyst beds (also referred to herein as fixed catalyst "baskets") or removable catalyst beds (also referred to herein as removable catalyst "baskets"). Although potentially less desirable, a BRFR comprising at least one catalyst zone that is a fixed catalyst basket and at least one catalyst zone that is a removable catalyst basket is also within the scope of this invention.

[0035] As noted above, the BRFR of this invention may comprise a fixed catalyst bed or a catalyst basket. A fixed bed BRFR according to an embodiment of this invention will now be described with reference to FIG. 2A. As noted above, in embodiments of the invention, the BRFR of this invention comprises a cylindrical outer casing surrounding at least five cylindrical concentric zones, including at least three annular vapor zones and at least two catalyst zones. The fixed bed BRFR 10 comprises a cylindrical outer vessel or reactor vessel 5 surrounding five cylindrical concentric zones including three annular vapor zones and two catalyst zones. The two catalyst zones comprise an outer catalyst zone 20A and an inner catalyst zone 20B, and the three annular vapor zones comprise an outer annular vapor zone 15A, a middle annular vapor zone 15B, and a central annular vapor zone 15C. The outer catalyst zone 20A is located between the outer annular vapor zone 15A and the middle annular vapor zone 15B, and the inner catalyst zone 20B is located between the middle annular vapor zone 15B and the central annular vapor zone 15C.

[0036] The outer catalyst zone 20A and the inner catalyst zone 20B may be demarcated by lattice baskets that may be bolted into place. Catalyst fixed beds or catalyst baskets may be provided with Vee-Wire® ^screens , wedge metal screens, or any suitable metal screen that separates two or more catalyst zones from three or more annular vapor zones. Vee- ^Wire® or Johnson Screens is a brand of wedge metal screens from Bilfinger Water Technologies GmbH. In embodiments of the invention, outer catalyst zone 20A and inner catalyst zone 20B comprise a reforming catalyst. The reforming catalyst may be any suitable reforming catalyst known to those skilled in the art. In embodiments of the invention, the reforming catalyst is the catalyst detailed herein below. The perforated plates 12 can be used to adjust the differential pressure.

[0037] As noted above, the BRFR in accordance with this invention further comprises a distribution pipeline configured to vertically enter the feed into the lower end of each of one or two of at least three annular steam zones and divert product from the lower end of each of one or the remaining two of the at least three annular steam zones. The fixed bed BRFR 10 includes distribution conduit 40. Distribution conduit 40 may be located substantially under or at the lower end of the cylindrical outer casing 5. Distribution conduit 40 includes conduits 42A, 42B, and 42C. Conduits 42A, 42B, and 42C are configured to introduce feed and/or product from outer annular vapor zone 15A, middle annular vapor zone 15B, and central annular vapor zone 15C, respectively. It is desirable that the distribution conduit 40 be able to function in such a way that the direction of flow can be changed. For example, conduit 42B may initially be used to introduce feed into middle annular steam zone 15B, conduit 42A being used to divert product from outer annular steam zone 15A and conduit 42C being used to divert product from central annular steam zone 15C. Subsequently, the flow direction can be changed (for example, without limitation, the process of regenerating or cleaning the reactor while removing coke, reaction by-products and contaminants, or the process of adding regenerating liquids can be improved by changing the direction of the process flow through the catalyst beds) using pipelines 42A and 42C , used to introduce feed or other gas into the outer annular vapor zone 15A and the central annular vapor zone 15C, respectively, while conduit 42B is used to divert product or other gas from the middle annular vapor zone 15B.

[0038] The distribution conduit 40 may further comprise a lateral conduit 43 configured to combined bleed gas from conduit 42A or 42B. For example, in the embodiment of the invention shown in FIG. 2A, side conduit 43 (which may or may not be vertically aligned along the fixed bed side of the BRFR 10) is fluidly connected to conduit 42A and conduit 42C, whereby the gas (e.g., product gas) vented through them can be combined. and retracted from BRFR 10 fixed bed.

[0039] As noted above, for a fixed bed or basket BRFR, one or more vents may be configured to remove catalyst from at least two catalyst zones. For example, in the embodiment of the invention illustrated in FIG. 2A, vents 44A and 44C are in fluid communication with outer catalyst zone 20A, and vent 44B is in fluid communication with inner catalyst zone 20B. The valves may be configured to control the amount of flow into and/or from conduits 42A, 42B, and 42C, between conduit 42A and conduit 42B, between conduit 42B and conduit 42C, between conduit 42A and side conduit 43, and between conduit 42C and conduit 42C. side conduit 43. For example, valve A may be located along conduit 42A where it connects to lateral conduit 43 and is configured to control the amount of flow through conduit 42A (for example, towards or away from the BRFR 10 fixed bed reactor vessel); valve B may be located along conduit 42C where it connects to side conduit 43 and is configured to control the amount of flow through conduit 42C (eg, towards or away from the reactor vessel); valve AA may be positioned to bypass valve A and configured to control a small amount of flow between conduit 42A and side conduit 43; and valve BB can be positioned so that it bypasses valve B (for example, no longer changing flow direction during the cycle, but providing a small amount of flow so that the zone does not stagnate), and can be configured to regulate a small amount of flow between line 42C and side pipeline 43.

[0040] The fixed bed reactor BRFR 10 may further comprise a removable cover 30 configured to seal the top of the reactor. Lid 30 may be fixedly connected to reactor flange 6 at the top of cylindrical outer casing 5. Lid 30 includes an upper dome 31 and a lid flange 32 which, as is known to those skilled in the art, may be fixedly connected to reactor flange 6 at the top of cylindrical outer casing 5 In embodiments of the invention, the flange 32 of the cover 30 is bolted to the flange 6 of the reactor.

[0041] In FIG. 2B illustrates a plan view of the top of the cylindrical outer vessel 5 of the fixed bed reactor BRFR 10 of FIG. 2A. On FIG. 2B clearly shows the interlayering of the outer catalyst zone 20A with the outer annular vapor zone 15A and the middle annular vapor zone 15B, as well as the interlayering of the inner catalyst zone 20B with the middle annular vapor zone 15B and the central annular vapor zone 15C. On FIG. 2B also shows how the reactor flange 6, firmly connected to the cylindrical outer casing 5, can be bolted to the flange 32 of the cover 30. The supports 7A and 7B can be an integral part of the outer catalyst zone 20A and the inner catalyst zone 20B and are configured to provide for them structures/supports. In embodiments of the invention, supports 7A and/or 7B may be omitted.

[0042] Packing 8 may be located around the annular groove of the outer zone 20A of the catalyst. Such packing 8 may comprise high temperature insulation, such as, but not limited to, ceramic fiber insulation in the form of a rope or blanket. ^Kaowool® is an example of ceramic fiber insulation available from Morgan Thermal Ceramics. The spacer ring 11 for circumferential alignment may serve as a flow restrictor for the outer annular vapor zone 15A. The spacer ring 11 may be welded to the housing or attached, as will be apparent to those skilled in the art. The inner caps 9 located at the top of the middle and central annular zones may be made of a metal similar to or compatible with the catalyst screens and baskets and may be bolted or welded to them. A solid metal plate 11 can be used to line the catalyst baskets inside the reactor 10. An outer cap can be welded to the outer casing 5 and Kaowool to allow expansion of the catalyst baskets.

[0043] As noted above, in embodiments of the invention, the BRFR of this invention comprises a removable bed or removable catalyst basket. A removable layer BRFR according to an embodiment of this invention will now be proposed with reference to FIG. 3A. As noted above, in embodiments of the invention, the BRFR of this invention comprises a cylindrical outer casing surrounding at least five cylindrical concentric zones, including at least three annular vapor zones and at least two catalyst zones. The BRFR 110 with removable catalyst basket comprises a cylindrical outer vessel or reactor vessel 105 surrounding five cylindrical concentric zones including three annular vapor zones and two catalyst zones. The two catalyst zones comprise an outer catalyst zone 120A and an inner catalyst zone 120B, and the three annular vapor zones comprise an outer annular vapor zone 115A, a middle annular vapor zone 115B, and a central annular vapor zone 115C. The outer catalyst zone 120A is located between the outer annular vapor zone 115A and the middle annular vapor zone 115B, and the inner catalyst zone 120B is located between the middle annular vapor zone 115B and the central annular vapor zone 115C.

[0044] The outer catalyst zone 120A and the inner catalyst zone 120B in a BRFR PO with a removable catalyst basket may be provided as catalyst baskets. The catalyst baskets can be removed from the BRFR through its top end. On FIG. 4A is a schematic diagram of an inner catalyst basket 120B', an outer catalyst basket 120A', and a cylindrical outer shell or reactor shell 105' in accordance with embodiments of this invention, detailing the removable catalyst baskets, and a reactor flange 106'. On FIG. 4B illustrates a plan view of the inner catalyst basket 120B' of FIG. 4A. On FIG. 4C illustrates a plan view of the outer catalyst basket 120A of FIG. 4A. Catalyst baskets 120A/120A' can be made from Vee- ^Wire® screens, wedge metal screens, or any suitable metal screen that separates two or more catalyst zones from three or more annular vapor zones. A perforated metal plate 114B may be located at the bottom of the inner catalyst basket 120B/120B'; a perforated metal plate 114A may be located at the bottom of the outer catalyst basket 120a/120A'.

[0045] In embodiments, the outer catalyst zone 120A/120A' and the inner catalyst zone 120B/120B' comprise a reforming catalyst. The reforming catalyst may be any suitable reforming catalyst known to those skilled in the art. In embodiments of the invention, the reforming catalyst is the catalyst described in detail herein below. Perforated plates 112 can be used to adjust the differential pressure.

[0046] As noted herein above with reference to the fixed bed BRFR 10, the BRFR according to this invention further comprises a distribution conduit configured to vertically introduce feed into the lower end of each of one or two of the at least three annular steam zones and product withdrawal from the lower end of each of one or two remaining of at least three annular steam zones. Removable catalyst basket BRFR 110 includes distribution conduit 140. Distribution conduit 140 may be located substantially under or at the lower end of the cylindrical outer casing 105. Distribution conduit 140 includes conduits 142A, 142B, and 142C. Conduits 142A, 142B, and 142C are configured to introduce feed and/or product from outer annular steam zone 115A, middle annular steam zone 115B, and central annular steam zone 115C, respectively. It is desirable that the distribution conduit 140 be able to function in such a way that the direction of flow can be changed. For example, conduit 142B may initially be used to introduce feed into middle annular steam zone 115B, conduit 142A being used to divert product from outer annular steam zone 115A and conduit 142C being used to divert product from central annular steam zone 115C. Subsequently, the flow direction can be changed (for example, without limitation, the process of regenerating or cleaning the reactor while removing coke, reaction by-products and contaminants, or the process of adding regenerating liquids can be improved by changing the direction of the process flow through the catalyst beds) using conduits 142A and 142C , used to introduce feed or other gas into the outer annular vapor zone 115A and the central annular vapor zone 115C, while conduit 142B is used to divert product or other gas from the middle annular vapor zone 115B.

[0047] The distribution conduit 140 may further comprise a lateral conduit 143 configured to vent gas from conduits 142A, 142B, and/or 142C in combination. For example, in the embodiment of the invention shown in FIG. 3A, side conduit 143 (which may or may not be vertically aligned along the side of reactor 110) is fluidly connected to conduit 142A and conduit 142C, whereby the gas (e.g., product gas) vented through it can be combined and withdrawn from reactor 110.

[0048] As noted herein above with reference to the fixed bed BRFR 10 of FIG. 2A, in a BRFR with a removable catalyst basket, the valves may be configured to control the amount of flow into and/or out of conduit 142A, 142B, and 142C, between conduit 142A and conduit 142B, between conduit 142B and conduit 142C, between conduit 142A and the lateral conduit 143, as well as between conduit 142C and side conduit 143. For example, valve A may be located along conduit 142A where it connects to side conduit 143 and is configured to control the amount of flow through conduit 142A (for example, towards the reactor vessel 110 or from it); valve B may be located along conduit 142C where it connects to side conduit 143 and configured to control the amount of flow through conduit 142C (eg, towards or away from reactor vessel 105); valve AA may be positioned as a bypass between conduit 142A and side conduit 143, and configured to control the amount of flow therebetween; and valve BB may be positioned as a bypass between conduit 142C and side conduit 143, and configured to control the amount of flow therebetween.

[0049] A BRFR 110 with a removable catalyst basket may further comprise a removable cover 130 configured to seal the top of the reactor. The lid 130 may be fixedly connected to the cylindrical outer casing 105 via the lid flange 132 and the reactor flange 106 . Lid 130 includes a top dome 131 and a lid flange 132, which, as known to those skilled in the art, can be fixedly connected to the reactor flange 106 at the top of the cylindrical outer casing 105. In embodiments of the invention, the flange 132 of the lid 130 is bolted to the reactor flange 106. The lid 130 may include a pressure pad 133A and a pressure pad 133B. When the reactor 110 is closed, the pressure pad 133A may align with the top of the inner central annular steam zone 115C. Similarly, when the reactor 110 is closed, the pressure plate 133B may align with the opening at the top of the middle annular steam zone 115B. On FIG. 3B illustrates a plan view of the underside of the lid 130 showing the lid flange 132, the pressure pad 133A, the pressure pad 133B, and the support structure 109A/B. The support structure 109A and the support structure 109B are configured to attach pressure pads 133A and 133B, respectively, to the cover 130 via springs 134A and 134B, respectively.

[0050] In FIG. 3C illustrates a plan view of the top of the cylindrical outer casing 105 of the reactor 110 of FIG. 3A. On FIG. 3C clearly shows the interlayering of outer catalyst zone 120A with outer annular vapor zone 115A and middle annular vapor zone 115B, as well as interlayering of inner catalyst zone 120B with middle annular vapor zone 115B and central annular vapor zone 115C. On FIG. 3C also shows how the reactor flange 106, firmly connected to the cylindrical outer casing 105, can be bolted to the flange 132 of the lid 130. The supports 107A and 107B can be an integral part of the outer catalyst basket 120A and the inner catalyst basket 120V and are provided with the possibility of providing a structure/support for them.

[0051] Packing 108 may be located around the annular groove of the outer zone 120A of the catalyst and between the spacer ring 111 for circumferential alignment. Such packing 8 may comprise high temperature insulation, such as, but not limited to, ceramic fiber insulation in the form of a rope or blanket. ^Kaowool® is an example of ceramic fiber insulation available from Morgan Thermal Ceramics. The circumferential alignment spacer 111, together with the packing 108, can serve as a flow restrictor for the outer annular vapor zone 115A. The spacer ring 111 for circumferential alignment may be welded to the housing or attached, as will be apparent to those skilled in the art. In the upper part of the central annular zone 115C, the inner cap 9 is not required because the cap is provided by 133A. A solid metal plate 111 can be used to line the catalyst baskets within the reactor 110. An outer cap can be welded to the outer casing 105 and Kaowool to allow expansion of the catalyst baskets.

[0052] As noted above, this document also discloses a bi-modal radial now guard bed reactor or "BRFGBR" (bi-modal radial now guard bed reactor). The BRFGBR comprises a cylindrical outer vessel or reactor vessel surrounding at least five cylindrical concentric zones, including at least two annular vapor zones, at least two catalyst zones, and a bed separation zone. At least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, and at least two annular vapor zones comprise an outer annular vapor zone and a central annular vapor zone. The outer catalyst zone is located between the outer annular vapor zone and the bed separation zone, and the inner catalyst zone is located between the bed separation zone and the central annular vapor zone. Thus, one of the at least three annular vapor zones in the BRFR is replaced by a bed separation zone in the BRFGBR. The BRFGBR further comprises a distribution conduit configured to vertically feed the feed into the lower end of the outer annular steam zone and withdraw the product from the lower end of the central annular steam zone, and can be configured to change the direction of this flow.

[0053] A radial flow bimodal guard bed reactor according to an embodiment of this invention will now be proposed with reference to FIG. 5A. BRFGBR 210 includes a cylindrical outer casing or reactor casing 205 surrounding an outer catalyst zone 220A and an inner catalyst zone 220B, an outer annular vapor zone 215A and a central annular vapor zone 215C, and a bed separation zone 215B. As with the fixed bed BRFR 10 and the removable catalyst basket BRFR 110, the at least two catalyst zones comprise an outer catalyst zone 220A and an inner catalyst zone 220B. The annular steam zones in BRFGBR 210 comprise an outer annular steam zone 215A, a bed separation zone 215B, and a central annular steam zone 215C (215C may be a solid perforated tube over which a 220B Vee-Wire® 220B internal sieve basket for catalyst is inserted/installed). The outer catalyst zone 220A is located between the outer annular vapor zone 215A and the layer separation zone 215B, and the inner catalyst zone 220B is located between the layer separation zone 215B and the central annular vapor zone 215C. Layer separation zone 215B contains a layer separation basket, which can be provided, for example, by means of Vee- ^Wire® screens, wedge metal screens, or any appropriate metal screens.

[0054] The outer and inner catalyst zones 220A and 220B, respectively, in the BRFGBR 210 may be provided as removable catalyst baskets similar to (though probably smaller) the removable catalyst baskets in the BRFR 110. Thus, the removable catalyst baskets catalyst can be removed from the BRFGBR through its top and essentially as described with respect to FIG. 3 and FIG. 4A-4C.

[0055] Like the fixed bed BRFR 10 and the removable catalyst basket BRFR 110, the BRFGBR of this invention further comprises a distribution conduit. In the embodiment of the invention according to FIG. 5A, distribution conduit 240 is configured to vertically introduce feed into the lower end of the outer annular vapor zone 215A and withdraw product from the lower end of the central annular vapor zone 215C. Distribution conduit 240 may be located substantially under or at the lower end of the cylindrical outer casing 205. Distribution conduit 240 includes conduits 242A and 242C. Conduits 242A and 242C are configured to introduce feed and/or withdraw product from the outer annular vapor zone 215A and the central annular vapor zone 215C, respectively. It is desirable that the distribution conduit 240 be able to function in such a way that the direction of flow can be changed. For example, conduit 242A may be used to introduce feed into outer annular vapor zone 215A, while conduit 242C is used to divert product from central annular vapor zone 215C. Subsequently, the flow direction can be changed (for example, without limitation, the process of regenerating or cleaning the reactor while removing coke, reaction by-products and contaminants, or the process of adding regenerating liquids can be improved by changing the direction of the process flow through the catalyst beds) using the pipeline 242C used to introduce feed or other gas into the central annular vapor zone 215C, while conduit 242A is used to divert product or other gas from the outer annular vapor zone 215A. As described in the embodiments of the invention of FIG. 2 and 3, the BRFGBR 210 may further comprise side conduit 243, distribution conduit 240, cover 230, packing 208 shown in FIG. 5A, the spacer ring 211 for circumferential alignment shown in FIG. 5A and/or supports 207A and 207B shown in FIG. 5V.

[0056] In FIG. 5B illustrates a plan view of the top of the cylindrical outer casing 205 of the reactor 210 of FIG. 5A. On FIG. 5B clearly shows the interlayering of the outer catalyst zone 220A with the outer annular vapor zone 215A and the layer separation zone 215B, as well as the interlayering of the inner catalyst zone 220B with the layer separation zone 215B and the central annular vapor zone 215C. On FIG. 5B also shows how the reactor flange 206, firmly connected to the cylindrical outer casing 205, can be bolted to the lid flange (eg, lid 30 via lid flange 32 of FIG. 2A).

[0057] In embodiments, the BRFGBR of this invention comprises a reforming catalyst (e.g., a reforming catalyst known to those skilled in the art or provided herein below) in an inner catalyst zone 220B and an outer catalyst zone 220A. In embodiments, the BRFGBR of this invention contains a reforming catalyst (e.g., a reforming catalyst known to those skilled in the art or provided herein below) in an inner catalyst zone 220B and a distinct catalyst in an outer catalyst zone 220A. In embodiments, the inner catalyst zone 220B comprises a reforming catalyst (eg, a reforming catalyst known to those skilled in the art or provided herein below), a sulfur adsorbing filler, or both. In embodiments of the invention, the outer zone 220A of the catalyst contains a filler that traps iron. Such sulfur adsorbing fillers and iron trapping fillers are known to those skilled in the art.

[0058] Most of the dimensions below will be suggested with reference to FIG. 4A-4C and FIG. 6 which is a schematic plan view of a bimodal radial flow reactor 10/110 in accordance with embodiments of this invention. In embodiments of the invention, the central annular steam zone 15C/115C/215C has a radius or width R ₁ =W ₁ in the range from about 1 foot (0.30 meters (m)) to about 2 feet (0.61 m), from about 1.5 feet (0.46 m) to about 2 feet (0.61 m) or from about 0.5 feet (0.15 m) to about 2 feet (0.61 m).

[0059] In embodiments of the invention, the inner catalyst zone or the 20V/120V/120V'/220V inner catalyst basket has a catalyst width or thickness W ₂ in the range of about 0.5 ft (0.15 m) to about 2 ft (0 .61 m), from about 1.5 feet (0.46 m) to about 2 feet (0.61 m) or from about 1 foot (0.30 m) to about 3 feet (0.91 m). In embodiments of the invention, the inner catalyst zone or the 20V/120V/120V'/220V inner catalyst basket has an outer radius R ₂ that is substantially equal to R ₁ +W ₂ . In embodiments of the invention, the inner catalyst zone or the 20V/120V/120V'/220V inner catalyst basket has an outer radius R ₂ in the range of about 2 feet (0.61 m) to about 4 feet (1.22 m), from about 3.5 feet (1.07 m) to about 4 feet (1.22 m) or about 1.5 feet (0.46 m) to about 4 feet (1.22 m) and the inside radius is essentially _R1 . In embodiments of the invention, the inner catalyst zone or inner basket for the 20V/120V/120V'/220V catalyst has an H ₁ catalyst height ranging from about 10 feet (3.05 m) to about 40 feet (12.19 m), from 10 ft (3.05 m) to about 50 ft (15.24 m) or from about 5 ft (1.52 m) to about 50 ft (15.24 m).

[0060] In embodiments, the middle annular vapor zone 15B/115B or bed separation zone 215B has a W ₃ catalyst width or thickness in the range of about 0.5 ft (0.15 m) to about 1.5 ft (0.46 m), from about 0.75 feet (0.23 m) to about 1.25 feet (0.38 m) or from about 0.25 feet (0.08 m) to about 2 feet (0.91 m) . In embodiments of the invention, the middle annular vapor zone 15B/115B or layer separation zone 215B has an outer radius R ₃ that is substantially equal to R ₂ +W3. In embodiments of the invention, R ₃ is in the range from about 2.25 feet (0.68 m) to about 6 feet (1.83 m), from about 2.5 feet (0.76 m) to about 5.5 feet (1.68 m) or from about 2.75 feet (0.84 m) to about 5.25 feet (1.60 m), and the inner radius is essentially equal to R ₂ .

[0061] In embodiments, the outer catalyst basket 20A/120A/120A'/220A has a W ₄ catalyst width or thickness ranging from about 0.75 feet (0.23 m) to about 1.75 feet (0.53 m), from about 1 ft (0.30 m) to about 1.5 ft (0.46 m), or from about 1 ft (0.30 m) to about 1.75 ft (0.53 m). In embodiments, the outer catalyst basket 20A/120A/120A'/220A has an outer radius R ₄ that is substantially equal to R ₃ +W ₄ . In embodiments of the invention, the outer catalyst basket 20A/120A/120A'/220A has an outer radius R ₄ ranging from about 3.25 feet (0.99 m) to about 7.5 feet (2.29 m), from about 3.25 feet (0.99 m) to about 7.75 feet (2.36 m) or about 3 feet (0.91 m) to about 7.25 feet (2.21 m) and the inside radius of essentially equal to R3. In embodiments of the invention, the outer catalyst basket 20A/120A/120A'/220A has an H _O catalyst height ranging from about 10 feet (3.05 m) to about 40 feet (12.19 m), from 10 feet (3. 05 m) to about 50 feet (15.24 m) or from about 5 feet (1.52 m) to about 50 feet (15.24 m).

[0062] In embodiments of the invention, the outer annular vapor zone 15A/115A/215A has a width or thickness W ₅ in the range from about 0.25 feet (0.08 m) to about 2 feet (0.61 m), from about 0 .50 feet (0.15 m) to about 1.25 feet (0.38 m) or from about 0.75 feet (0.23 m) to about 1.0 feet (0.31 m). In embodiments of the invention, the outer annular vapor zone 15A/115A/215A has an outer radius R ₅ that is substantially equal to R ₄ +W ₅ . In embodiments, the outer annular vapor zone 15A/115A/215A has an outer radius R ₅ substantially equal to ½ D _R and an inner radius substantially equal to R ₄ . In embodiments of the invention, the outer annular steam zone 15A/115A/215A has an outer radius R ₅ in the range of about 3.00 feet (1.07 m) to about 10 feet (3.05 m), from about 3.5 feet ( 1.07 m) to about 9 feet (2.74 m) or from about 3.75 feet (1.14 m) to about 10 feet (3.05 m).

[0063] In embodiments of the invention, the cylindrical outer vessel or reactor vessel 5/105/105'205 has an internal diameter D _R and a radius equal to ½ D _R , that is, in the range from about 3 feet (0.91 m) to about 10 ft (3.05 m), about 3 ft (0.91 m) to about 10 ft (3.05 m), or about 4 ft (1.22 m) to about 9 ft (2.74 m). In embodiments of the invention, the cylindrical outer vessel or reactor vessel 5/105/1057205 has a vertical wall height Hp ranging from about 10 feet (3.05 m) to about 40 feet (12.19 m), from 10 feet (3.05 m) to about 50 feet (15.24 m) or from about 5 feet (1.52 m) to about 50 feet (15.24 m), and the total vertical height H _TR is H _R plus ΔH, where ΔH is in the range of about 0.5 inches (0.01 m) to about 6 inches (0.15 m), from about 1 inch (0.02 m) to about 1 ft (0.31 m) or from about 0, 5 inches (0.01 m) to about 1 foot (0.31 m).

[0064] In one embodiment, the outer catalyst zone 20A/120A/120A'/220A contains a volume of catalyst that is approximately equal to the volume of catalyst in the inner catalyst zone 20B/120B/120B'/220B. In an embodiment, two or more of the outer annular vapor zone 15A/115A, the middle annular vapor zone 15B/115B, and/or the central annular vapor zone 15C/115C have the same or similar volume (e.g., 1, 2, 3, 4, 5 , 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20%).

[0065] In embodiments, the BRFR is a taller reactor (e.g., with a reactor height H _p greater than or equal to about 20, 30, or 40 feet (6.1, 9.1, or 12.2 m) with a smaller diameter ( for example, with a reactor diameter D _R less than or equal to approximately 6, 7, or 8 feet (1.8, 2.1, or 2.4 m), which can facilitate operation with a lower pressure drop.(As will be discussed later in this document , the use of catalyst pellets of different diameters in different catalyst zones can also serve to reduce pressure drop buildup.) In alternative embodiments, the BRFR is a larger diameter reactor (e.g., with a DR reactor diameter greater than or equal to about 20, 30, or 40 feet ( 6.1, 9.1 or 12.2 m), with large volumes of catalyst in the outer catalyst zone or in the outer catalyst basket 20A/120A/120A'/220A, and/or in the inner catalyst zone or in the inner basket 20B/ 12 0V/120V'/220V for catalytic converter. This larger total catalyst inventory can help increase cycle times. Such longer cycle times may include catalyst cycles greater than or equal to 3, 4 or 5 years.

[0066] As noted above, the radial flow reactors of this invention may be suitable for use with a variety of catalysts known to those skilled in the art. In embodiments of the invention, the BRFR of this invention is used to carry out an endothermic reaction. In embodiments of the invention, BRFR is used to carry out reforming reactions. In embodiments of the invention, the outer catalyst zone 20A/120A/120A'/220A, the inner catalyst zone 20B/120B/120B'/220B, or both zones contain a reforming catalyst. In embodiments of the invention, the inner zone 20B/120B/120B'/220B of the catalyst contains a catalyst that differs from the catalyst in the outer zone 20A/120A/120A'/220A of the catalyst in at least one parameter selected from the group consisting of size, shape , composition and loading. The inclusion of a different catalyst may allow control of the pressure drop in the inner catalyst zone, the outer catalyst zone, or both. In embodiments of the invention, the pressure drop across the inner 20V/120V/120V'/220V zone of the catalyst is the same or substantially the same (e.g., within ± 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 , 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20%) as pressure drop across the outer zone 20A/120A/120A'/220A of the catalyst.

[0067] In some embodiments, the reforming catalyst is an AROMAX® catalyst as described, for example, in US Pat. No. 9,085,736. The reforming catalyst may contain an inorganic support, a Group VIII metal such as platinum, and one or more halides such as fluorine, chlorine, iodine, bromine, or combinations thereof. In some embodiments, the catalyst may contain Group VIII metals on an inorganic support, such as platinum on alumina, Pt/Sn on alumina, and Pt/Re on alumina. In other embodiments of the invention, the catalyst may contain noble metals of group VIII on a zeolite carrier, for example, Pt, Pt/Sn and Pt/Re on zeolite carriers, which may contain a binder and zeolites, for example, L-zeolites, ZSM-5, silicalite and beta; and noble metals of group VIII on L-zeolites in exchange for alkali and alkaline earth metals. The catalyst may contain a large-pore zeolite as an inorganic carrier filled with at least one Group VIII metal. In embodiments, the Group VIII metal may include platinum, which may be more selective for dehydrocyclization and which may be more stable under reforming reaction conditions than other Group VIII metals. In other embodiments, the catalyst may contain a Group VIII metal, such as rhenium, or a Group IV metal, or a semi-metal, such as tin.

[0068] In one embodiment, the catalyst may include a non-acidic catalyst that may contain a non-acidic zeolite carrier as an inorganic carrier, a Group VIII metal, and one or more halides. Suitable halides include chloride, fluoride, bromide, iodide, or combinations thereof. Suitable Group VIII metals include iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum, or combinations thereof.

[0069] Inorganic supports for reforming catalysts (eg, aromatization catalysts) can generally include any inorganic oxide. These inorganic carriers include associated large-pore aluminosilicates (zeolites), amorphous inorganic oxides, and mixtures thereof. Large pore aluminosilicates include, but are not limited to, L-zeolite, Y-zeolite, mordenite, omega-zeolite, beta-zeolite, and the like. Amorphous inorganic oxides include, but are not limited to, alumina, silicon dioxide, and titanium dioxide. Suitable binders for inorganic carriers include, but are not limited to, silica, alumina, clays, titanium dioxide, magnesium oxide, and combinations thereof.

[0070] The inorganic carrier may be an aluminosilicate, such as a zeolite. In embodiments of the invention, the reforming catalyst may include a zeolite catalyst. It is known that zeolite materials, both natural and synthetic, have catalytic properties for many hydrocarbon processes. The term "zeolite" generally refers to a specific group of hydrated crystalline metal aluminosilicates. These zeolites have a SiO ₄ and AlO ₄ tetrahedral network structure in which the aluminum and silicon atoms are linked into a three-dimensional framework by means of shared oxygen atoms. The cavities and channels throughout the crystalline material of the zeolites are interconnected and can generally be sized to allow selective separation of hydrocarbons. In a three-dimensional framework, the ratio of oxygen atoms to the total number of aluminum and silicon atoms can be equal to 2. Said framework exhibits negative electrovalence, which is usually balanced by the inclusion of cations in the crystal, for example, metals, alkali metals, alkaline earth metals or hydrogen. Thus, zeolites are a group of natural or synthetic hydrated aluminosilicate minerals that typically contain alkali and alkaline earth metals. Zeolites are characterized by a lattice structure that encompasses interconnected cavities occupied by ion-exchange large metal cations, such as potassium, and water molecules, providing reversible dehydration. The actual formula of the zeolite can change without changing the crystal structure. In an embodiment of the invention, the molar ratio of silicon to aluminum (Si/Al) in the zeolite can vary from about 1.0 to about 3.5.

[0071] In embodiments of the invention, the reforming catalyst may contain a large pore zeolite. The term "large pore zeolite" can be defined as a zeolite having an effective pore diameter of from about 6 angstroms (Å) to about 15 Å; alternatively, from about 7 Å to about 9 Å. Examples of large pore crystalline zeolites are L-zeolite, Zeolite X, Zeolite Y, Omega-zeolite, Beta-zeolite, ZSM-4, ZSM-5, ZSM-10, ZSM-12, ZSM-20, REY, USY, RE-USY , LZ-210, LZ-210-A, LZ-210-M, LZ-210-T, SSZ-24, SSZ-26, SSZ-31, SSZ-33, SSZ-35, SSZ-37, SSZ-41 , SSZ-42, SSZ-44, MCM-58, mordenite, mazzite, faujasite and combinations thereof. In one embodiment of the invention, the large pore zeolite may have an isotype framework structure. In one embodiment of the invention, the reforming catalyst may contain an L-zeolite.

[0072] L-zeolite, its X-ray pattern, its properties and methods for its preparation are described in detail in US patent No. 3,216,789, the contents of which are incorporated herein by reference. Zeolite X is described in US Pat. No. 2,882,244. Mazzit is described in US Pat. Nos. 4,503,023 and 4,021,447. Mordenite is described in US Pat. No. 4,503,023. Zeolite Y is described in US Pat. No. 3,130,007. US Patents #3,216,789; 2,882,244; 4,503,023; 4,021,447; and 3,130,007 are incorporated herein by reference to show zeolites useful in reforming processes.

[0073] In embodiments of the invention, the reforming catalyst may contain a large pore L-zeolite. L-type zeolite catalysts are a subgroup of zeolite catalysts. Typical L-type zeolites contain mole ratios of oxides according to the following formula:

where "M" represents at least one exchangeable cation, for example, barium, calcium, cerium, lithium, magnesium, potassium, sodium, strontium and zinc, as well as non-metallic cations, for example, hydronium and ammonium ions, which can be replaced by others exchange cations without causing a significant change in the basic crystal structure of the L-type zeolite. "n" in the above formula represents the valency of "M"; "x" can be equal to 2 or more; and "y" is equal to the number of water molecules contained in the channels or voids communicating with the zeolite.

[0074] Bound potassium L-type zeolites or KL zeolites have been found to be particularly desirable. In the context of this document, the term "zeolite KL" means L-type zeolites, in which the main cation M included in the zeolite may include a potassium cation. The KL zeolite can be cation exchanged or impregnated with another metal and one or more halides to form a platinum impregnated halogenated zeolite or a Pt halide catalyst supported on the KL zeolite. In one embodiment, the zeolite may comprise an L-type zeolite. In embodiments, the reforming catalyst may comprise an L-type potassium zeolite, hereinafter referred to as KL-zeolite, which refers to L-type zeolites in which the main exchangeable cation, M, included in the zeolite is potassium.

[0075] One or more Group VIII metals may be added to the catalyst support to form a metallized catalyst support. The metal can be added to the catalyst support using a variety of known and conventional methods such as ion exchange, initial moisture, pore filling, impregnation, vapor deposition, and so on. In embodiments of the invention, platinum and optionally one or more halides may be added to the zeolite carrier by any suitable method, for example, impregnating with a solution of a platinum-containing compound and one or more halide-containing compounds. In one embodiment of the invention, the metal may be added to the catalyst support by impregnation with a metal-containing solution. The metal in the metal-containing solution may include at least one Group VIII metal; alternatively Pt, Pd, Rh, Ir, Ru, Os, or combinations thereof. In one embodiment of the invention, the metal may include platinum, which may be added to the catalyst support by contact with a metal-containing solution containing at least one platinum-containing compound. Examples of platinum-containing compounds suitable for contacting with a catalyst support include, without limitation, platinum compounds which form positively charged platinum complex ions in solution, eg platinum salts, eg chlorides and nitrates; complexes of platinum with amines; or their combinations. For example, the platinum-containing compound may be any degradable platinum-containing compound, including, but not limited to, ammonium tetrachloroplatinate, chloroplatinic acid, diammineplatinum(II) nitrite, bis(ethylenediamine)platinum(II)chloride, platinum(II)acetylacetonate ), dichlorodiammineplatinum, platinum(II) chloride, tetraammineplatinum(II) hydroxide, tetraammineplatinum chloride, and tetraammineplatinum(II) nitrate. In one embodiment of the invention, the source of platinum may contain tetraamine platinum chloride (TAPC). The amount of platinum in the metallized catalyst support may range from about 0.1 to about 5% by weight, alternatively from about 0.1 to about 3% by weight, alternatively from about 0.3 to about 1.8 % wt.

[0076] In an embodiment of the invention, the catalyst may comprise a large pore zeolite support containing a platinum compound and at least one halide. One or more halides can be added to the catalyst support by contacting with a halogenated compound to form a halide catalyst support. The halides may be added to the catalyst support separately; alternatively, the halides can be added to the catalyst support at the same time. Such halides may be included during the addition of the metal, alternatively the halides may be included in a separate step, which may be carried out before or after the addition of the metal, to form the halide metallized catalyst support. Examples of suitable halides include, without limitation, fluoride, chloride, bromide, iodide, or combinations thereof. Such halides may be introduced as an ammonium halide compound.

[0077] In an embodiment, the catalyst may comprise a large pore zeolite carrier with a platinum-containing compound and at least one ammonium halide compound. The ammonium halide compound may include one or more compounds represented by the formula N(R) ₄ X, where X may include a halide, and where R is hydrogen or a molecule containing a substituted or unsubstituted carbon chain having 1-20 carbon atoms, while all Rs can be the same or different. In an embodiment of the invention, R may include methyl, ethyl, propyl, butyl, or combinations thereof. Examples of a suitable organic ammonium compound represented by the formula N(R) ₄ X may include ammonium chloride, ammonium fluoride, and tetraalkylammonium halides, for example, tetramethylammonium chloride (TMAC), tetramethylammonium fluoride (TMAF), tetraethylammonium chloride, tetraethylammonium fluoride, tetrapropylammonium chloride, fluoride tetrapropylammonium chloride, tetrabutylammonium chloride, tetrabutylammonium fluoride, methyltriethylammonium chloride, methyltriethylammonium fluoride, or combinations thereof.

[0078] In an embodiment of the invention, the ammonium halide compound may include at least one acid halide and at least one ammonium hydroxide represented by the formula N(R') ₄ (DH, where R' may include hydrogen or a molecule containing a substituted or unsubstituted carbon a chain having 1-20 carbon atoms, all R' may be the same or different.In an embodiment, R' may include methyl, ethyl, propyl, butyl, or combinations thereof.Examples of suitable ammonium hydroxide represented by the formula N(R' ) ₄ OH may include ammonium hydroxide, tetraalkylammonium hydroxides, for example, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and combinations thereof.Examples of suitable acid halides may include HCl, HF, HBr, HI, or combinations thereof.

[0079] In one embodiment of the invention, the ammonium halide compound may include (a) a compound represented by the formula N(R) ₄ X, where X may include a halide and where R is hydrogen or a molecule with a substituted or unsubstituted carbon chain having 1- 20 carbon atoms, wherein all R's may be the same or different, and (b) at least one acid halide and at least one ammonium hydroxide represented by the formula N(R') ₄ OH, where R' may include hydrogen or a molecule with substituted or unsubstituted carbon chain having 1-20 carbon atoms, while all R' may be the same or different.

[0080] The halide-containing compound may further include an ammonium halide, such as ammonium chloride, ammonium fluoride, or both, in various combinations with the ammonium halide compounds described above. More specifically, ammonium chloride, ammonium fluoride, or both may be used (a) as previously described with a compound represented by the formula N(R) ₄ X, where X may include a halide and where R is hydrogen or a molecule with a substituted or an unsubstituted carbon chain having 1-20 carbon atoms, all R being the same or different, and/or (b) as described previously with at least one acid halide and at least one organic ammonium hydroxide represented by the formula N(R') ₄ OH, where R' may include a molecule with a substituted or unsubstituted carbon chain having 1-20 carbon atoms, while all R' may be the same or different. For example, the first fluoride- or chloride-containing compound may be introduced as a tetraalkylammonium halide, and the second fluoride- or chloride-containing compound may be introduced as an ammonium halide. In one embodiment of the invention, tetraalkyl ammonium chloride may be used with ammonium fluoride.

[0081] In one embodiment of the invention, the reforming catalyst may include a metallized halide carrier, and the amount of halide in the catalyst is in the range from about 0.05% wt. up to about 5.0% wt. In one embodiment of the invention, the halide catalyst carrier may contain chloride present in an amount of from about 0.1% wt. up to about 5% wt.; alternatively from about 0.1% wt. up to about 3% wt.; alternatively from about 0.3% wt. up to about 1.8% wt. In one embodiment of the invention, the halide catalyst carrier may contain fluoride present in an amount of from about 0.1% wt. up to about 5% wt.; alternatively from about 0.1% wt. up to about 3% wt.; alternatively from about 0.3% wt. up to about 1.8% by weight. In one embodiment, the halide catalyst support may contain both chloride and fluoride, which may be present in a C1:F ratio of from about 1:10 to 10:1; alternatively, from about 1:5 to 5:1; alternatively, from about 1:2 to 2:1.

[0082] In embodiments of the invention, the catalyst may comprise a low acid L-type potassium zeolite support associated with silica, platinum, chloride, and fluoride. In embodiments, the reforming catalyst can easily convert nearly linear C ₆ s (ie, C ₆ hydrocarbons with no more than one branch), but cannot easily convert C ₆ hydrocarbons with more than one branch, such as dimethylpentane. Such easily convertible C ₆ hydrocarbons are referred to herein as "transformable C ₆ ". In some embodiments, the reforming catalyst comprises a low acid L-type potassium zeolite support associated with silica, platinum, chloride, and fluoride. In embodiments of the invention, the disclosed method provides a conversion of more than about 75%; alternatively, more than about 80%; alternatively, more than about 83% C ₆ convertible.

[0083] Examples of catalysts and reactor systems suitable for use with the reactors, systems and methods described herein are ^AROMAX® processes and catalysts available from Chevron Phillips Chemical Company of The Woodlands, Texas. A specific example of a suitable commercially available reforming catalyst is the ^AROMAX® II catalyst available from Chevron Phillips Chemical Company LP of The Woodlands, Texas. Suitable reforming catalysts are also disclosed in Wu US Pat. as if it were reproduced in its entirety.

[0084] Also disclosed herein is a method for using BRFR in accordance with this invention. In embodiments of the invention, as noted herein above, BRFR is used in catalytic hydrocarbon reforming to convert refinery naphthas distilled from crude oil (generally low octane) into high octane liquid products or "reformates" that are premium blends for high octane gasoline. In the specified technological process, low-octane linear hydrocarbons (paraffins) are converted into branched alkanes (isoparaffins) and cyclic naphthenes, which are then partially dehydrogenated to obtain high-octane aromatic hydrocarbons.

[0085] In embodiments of the invention, the hydrocarbon feed introduced into the BRFR (eg, aromatization reactor) contains non-aromatic hydrocarbons having at least six carbon atoms. In embodiments of the invention, the hydrocarbon feed contains a combination of hydrocarbons having from about five to about nine carbon atoms. In embodiments of the invention, the hydrocarbon feedstock for BRFR contains a mixture of hydrocarbons, including hydrocarbons from C ₆ to C ₈ containing up to about 10% wt. C ₅ and more light hydrocarbons (C ₅ ^- ) by weight of raw materials; alternatively up to about 15% wt. C ₅ or more light hydrocarbons (C ₅ ^- ), and containing up to about 10% wt. With ₉ and more heavy hydrocarbons (C ₉ ⁺ ) from the mass of raw materials. Low levels of C ₉ ⁺ and C ₅ ^- hydrocarbons maximize the yield of valuable aromatics. Coke formation can be influenced by coke-forming components such as cyclopentane and C9 ⁺ compounds in the feed. In some embodiments, the feed maximizes the percentage of C ₆ hydrocarbons. Such a feedstock can be obtained by separating a hydrocarbon feedstock, such as crude naphtha, into a light hydrocarbon feedstock fraction and a heavy hydrocarbon feedstock fraction, and use a light cut in the feedstock. In embodiments of the invention, the feed maximizes the conversion of convertible C ₆ . In embodiments of the invention, the raw material contains up to about 50% wt. convertible With ₆ ^- ; alternatively up to 60% wt. convertible With ₆ ; alternatively up to 70% wt. convertible With ₆ from the mass of raw materials.

[0086] In certain embodiments, the feedstock contains naphtha. The naphtha feed may contain a light hydrocarbon with a boiling point in the range of about 70°F (21°C) to about 450°F (232°C). The naphtha feed may contain aliphatic, naphthenic or paraffinic hydrocarbons. These aliphatic and naphthenic hydrocarbons can be converted at least in part to aromatic hydrocarbons in BRFR or in a reactor catalyst system containing BRFR. Although catalytic aromatization generally means the conversion of naphtha, other feedstocks can also be processed to produce an aromatic rich product. Therefore, although the conversion of naphtha may be one embodiment of the invention, this invention may be applicable to the conversion or aromatization of various feedstocks, for example, paraffinic hydrocarbons, olefinic hydrocarbons, acetylenic hydrocarbons, cyclic paraffinic hydrocarbons, cyclic olefinic hydrocarbons and mixtures thereof, and, in particular saturated hydrocarbons.

[0087] In one embodiment, the feedstock may be substantially free of sulphur, nitrogen, metals, and other known poisons for reforming catalysts. In one embodiment, the hydrocarbon stream may have a sulfur content in the range of less than 200 ppbw, alternatively less than 100 ppbw, alternatively from about 10 parts per billion by weight (ppbw) to about 100 ppbw. If such poisons are present, they can be removed using methods known to those skilled in the art. In some embodiments, the feedstock may be purified first using conventional hydrotreating methods and then using sorbents to remove remaining poisons, as is known to those skilled in the art. Such hydrotreating methods and sorbents can be used in the systems and methods described herein.

[0088] The reforming reactions can proceed under process conditions that thermodynamically promote the dehydrocyclization reaction and limit unwanted hydrocracking reactions. Operating ranges for a typical catalytic reforming process, such as an aromatization process, may include reactor inlet temperatures from 700°F (371°C) to 1050°F (566°C); system pressure from 0 psig (psig) (0 MPag) to about 500 psig (3.447 MPa g); a hydrogen recycling rate sufficient to obtain a hydrogen to hydrocarbon molar ratio of feedstock to the reforming reactor zone from 0.1 to 20; and an hourly space velocity of the hydrocarbon feed liquid over the reforming catalyst from 0.1 to 10. Operating temperatures may generally include reactor inlet temperatures from about 700°F to about 1050°F.

[0089] As shown in FIG. 2 and 3, feed may be introduced into the BRFR middle annular steam zone 15V/115V through a first port or inlet at the bottom of the 15V/115V mid annular steam zone and a second port or inlet at the bottom of the 15V/115V mid annular steam zone through pipeline 42B/142B of the distribution pipeline 40/140, and the product containing aromatic hydrocarbons can be withdrawn from the outer annular vapor zone 15A/115A through the first hole or outlet at the bottom of the outer annular vapor zone 15A/115A and the second hole or outlet in the lower part of the outer annular steam zone 15A/115A through pipeline 42A/142A, and also diverted from the central annular steam zone 15C/115C through pipeline 42C/142C, respectively, distribution pipeline 40/140. In such embodiments, a 15V/115V middle annular steam zone located between the 15C/115C central annular steam zone and the 15A/115A outer annular steam zone can be used as a process inlet, with the 15C/115C central annular steam zone and outer annular vapor zone 15A/115A can be used as process outlets.

[0090] In alternative embodiments, feed may be introduced into the central annular steam zone 15C/115C BRFR through conduit 42C/142C of distribution conduit 40/140, and product containing aromatics may be withdrawn from the outer annular steam zone 15A/115A and the middle annular steam zone 15B/115B through pipelines 42A/142A and 42B/142B, respectively, of the distribution pipeline 40/140. In such embodiments, the central annular vapor zone 15C/115C may be used as the process inlet, while the middle annular vapor zone 15V/115V and the outer annular vapor zone 15A/115A may be used as the process outlets.

[0091] In embodiments of the invention, one inlet and outlet is controlled by valve A and valve B, while valves AA and BB can be opened to eliminate dead zones. In embodiments, valves AA and BB are smaller than valves A and B. When used, feed can be staggered to one catalyst bed at a time. For example, feed may be introduced into one inlet (for example, by opening valve A and closing valve B) during the first half of the cycle, and then introduced into a second inlet (for example, by opening valve B and closing valve A) during second half of the cycle. In this mode of operation, a very small flow can be introduced into the catalyst bed, which is not currently used, to minimize or eliminate the presence of dead zones. In such modes, when valve A is open, valve BB can also be open, and valves B and AA are closed.

[0092] In embodiments, the inner catalyst zone or inner catalyst basket 20B/120B/120B'/220B and the outer catalyst zone or outer catalyst basket 20A/120A/120A'/220A are loaded with different types/compositions of catalysts, catalysts of different sizes , catalysts of different shapes and/or catalysts with different percentages/loads of precious metals. The use of catalyst of different diameter/volume/size in the inner catalyst zone or inner basket 20V/120V/120V'/220V for the catalyst and the outer zone of the catalyst or outer basket 20A/120A/120A'/220A for the catalyst can reduce the pressure drop during operation . In some embodiments, the catalyst in the outer catalyst zone 20A/120A/120A'/220A has a smaller average annular diameter and/or pellet volume than the catalyst in the inner catalyst zone or inner catalyst basket 20B/120B/120A'/220B. In other embodiments, the catalyst in the outer zone 20A/120A/120A'/220A of the catalyst has a larger average annular diameter and/or pellet volume than the catalyst in the inner zone 20B/120B/120B'/220B of the catalyst. In embodiments of the invention, a middle annular steam zone 15B/115B is used as a heat input zone between the inner catalyst zone or inner catalyst basket 20B/120B/120B' and the outer catalyst zone or outer catalyst basket 20A/120A/120A' within the BRFR. Thus, hydrocarbon feed may be introduced into the central annular vapor zone 15C/115C or the outer annular vapor zone 15A/115A, and product may be withdrawn from the outer annular vapor zone 15A/115A or the central annular vapor zone 15C/115C, respectively. In embodiments of the invention, additional heat input to the middle annular steam zone 15B/115B is provided by hydrocarbon feedstock and/or a hydrogen stream directed from the outlet of a heat transfer device (eg, furnace or flame heater); in such an embodiment, the conduit is configured to introduce "hot" hydrocarbon feedstock and/or hydrogen from the outlet of the heating device into conduit 42V/142V of distribution conduit 40/140 to enter the middle annular steam zone 15V/115V. In embodiments of the invention, the radiant heating tubes, configured to pass the heat source flow through the tubes or other reactor internals, are arranged to provide additional heat to the catalyst zone(s). In such embodiments, the coolant does not enter the catalyst bed(s), but rather provides radiant heat through pipes or other internals of the reactor. For example, the heat transfer fluid may be provided by a hot effluent (e.g., a reformer effluent containing aromatic hydrocarbons), electrical heating elements, a hot oil system, flue gas, and/or other heating method known to those skilled in the art.

[0093] As noted above, the BRFRs of this invention are provided with distribution piping configured to change the direction of steam flow through the catalyst zones. Reversing the direction of the process flow can be used to provide better utilization of the catalyst, for example when larger diameter catalyst beds are to be used. Reversing the steam flow can also improve the distribution of reactants during special procedures such as in situ catalyst regeneration.

[0094] Also disclosed herein is an integrated system comprising two or more bimodal radial flow reactors in accordance with this invention. Such an integrated system may comprise any two of the BRFRs disclosed herein, selected from a fixed bed BRFR, a removable catalyst basket BRFR, and a BRFGBR. In embodiments of the invention, the integrated system in accordance with this invention comprises a BRFGBR before one or more BRFRs with removable catalyst baskets. In embodiments of the invention, the integrated system in accordance with this invention comprises a BRFGBR before one or more fixed bed BRFRs. In embodiments of the invention, the integrated system in accordance with this invention comprises one or more BRFRs with a removable catalyst basket in front of one or more fixed bed BRFRs. In embodiments of the invention, an integrated system in accordance with this invention comprises a BRFGBR in front of one or more BRFRs with removable catalyst baskets, with one or more of the BRFRs with removable catalyst baskets themselves in front of one or more fixed bed BRFRs.

[0095] An integrated system in accordance with an embodiment of this invention will now be described with reference to FIG. 7. Embodiment Integrated System I of FIG. 7 contains a first reactor R1, a second reactor R2 and a third reactor R3. In embodiments of the invention, the first reactor R1 is a BRFGBR according to this invention, the second reactor R2 is a BRFR with a removable catalyst basket according to this invention, and the third reactor R3 is a fixed bed BRFR according to an embodiment of this invention. . In embodiments of the invention, the first, second and/or third reactors R1, R2 and/or R3 are reformers containing a reforming catalyst. Therefore, each reactor can be connected to a heating device in front of it. For example, in FIG. 7 the HI heat exchanger serves to transfer heat between the hot product stream of the system and the feed, thus heating/evaporating the feed before entering the BRFGBR R1, and FH flame heaters can be used to increase the temperature of the reactor effluent before entering the next reactor in series connected reactors.

[0096] In embodiments of the invention, the integrated system comprises two or three BRFRs with a removable catalyst basket and two or three fixed bed BRFRs. A diagram of such a system II is shown in Fig. 8. System II comprises a guard bed reactor, GR, connected in series with three BRFRs with removable catalyst basket, R1, R2, and R3, and three fixed bed BRFRs, R4, R5, and R6. The feed/outlet heat exchanger HI is configured to increase the temperature/evaporation of the hydrocarbon feed HC introduced therein by heat exchange with the system product P6. Flame preheaters F1-F6 serve to raise the temperature of the PGR-P6 effluent from the respective reactor before entering the next reactor connected in series, as is known in the reforming art.

[0097] In embodiments of the invention, the volume of each of the three bimodal radial flow reactors R1, R2 and R3 with a removable catalyst basket is less than the volume of each of the three bimodal fixed bed radial flow reactors R4, R5 and R6. In embodiments of the invention, BRFRs with a removable catalyst basket have a catalyst volume that is at least 10%, 20%, or 30% less than the volume of catalyst in a fixed bed BRFR. In embodiments, the GR shield reactor is a BRFGBR, such as BRFGBR 210 of FIG. 5A and 5B and includes an inner catalyst basket, such as the inner catalyst basket 220V of FIG. 5A containing a reforming catalyst and/or sulfur adsorbent filler and an outer catalyst basket, such as the outer catalyst basket 220A of FIG. 5A containing an iron trapping filler.

[0098] The BRFRs of this invention can provide a number of advantages over conventional radial flow reactors. Without limitation, a number of potential advantages will be described below in this document. The configuration of the reactor internals to provide at least three annular steam zones and at least two catalyst zones such that there is adequate separation and spacing between the outer annular steam zone, the middle annular steam zone and the central annular steam zone and at least two catalyst zones which in embodiments of the invention will improve catalyst utilization. Using the embodiments of the system and method disclosed herein, the catalyst volume can be divided (eg, in half) and each half can be used differently. As noted above, reforming reactions, such as the AROMAX® processes, are highly endothermic. As the vaporized feed passes through the reactor bed from the undulations to the central tube, the catalyst temperature can rapidly drop below the activation temperature for the dehydrogenation reactions. Thus, when the working catalyst is deactivated, the reactor inlet temperature generally rises to compensate for the loss in selectivity. The high temperature in the decontamination zones leads to intense cracking reactions, which determine the criteria for the end of the cycle. Thus, most of the catalyst in the vicinity of the steam exit zone is not fully utilized. The BRFRs described herein can provide more complete catalyst utilization than conventional radial flow reactors, in which the catalyst near the (single) vapor exit zone tends not to be fully utilized at the end of the run. In embodiments of the invention, the more complete use of the catalyst offered by the BRFRs disclosed herein may allow for a reduction in the number of furnaces and reactors in the reactor line. For example, the use of one or more BRFRs of this invention in a reformer line comprising a series of reformers connected in series and associated furnaces may reduce the total number of reactor/furnace pairs required to achieve the desired conversion or selectivity. In addition, providing a more complete use of the catalyst can result in a reduction in the amount of catalyst required for a given cycle time and/or desired product yield without sacrificing operating life. In the context of this document, the term “totally used” or “totally used” catalyst refers to a catalyst that, at the end of the cycle (which is determined by economic factors associated with the production of undesired by-products), yields less than desired product, for example, product quality decreases due to cracking, which results in the formation of more light fractions, estimated as fuel gas. For the Aromax® process, this end-of-cycle condition can be equated to 65%, 70%, or 75% catalyst consumed. In embodiments of the invention, the BRFR of the invention provides a longer cycle time to catalyst change compared to a conventional single modal radial flow reformer operating at equivalent selectivity. In embodiments of the invention, the cycle time is increased by 25, 30, or 35 percent.

[0099] The more complete catalyst utilization afforded by the BRFR of this invention may allow lower reactor temperature operation at the end of the run. This end-of-cycle temperature reduction results in lower internal metal temperatures, which can result in a concomitant reduction in carburization and metal losses in BRFR furnace tubes. In addition, the BRFRs of this invention may thus operate under near isothermal conditions, which may result in improved selectivity.

[00100] Introducing feed vertically into the BRFR vapor zone(s) can eliminate the need for separate flow distributors, disc overlay plates, which are typical means of providing flow diversion at the top of the reactor bed, and associated methods of bolting for attachment overlay plates. Because the feed entry line and the product exit line are both located at the bottom of the BRFR disclosed herein, fewer piping may be required compared to conventional radial flow reactors. The design of the BRFRs disclosed herein may eliminate the support bead fill typically used in radial flow reactors. In embodiments of the invention, the bottom carrier is omitted due to the design of the reactor internals, and the carrier, which is typically mounted at the top of the radial flow reactor, can also be omitted as only a small bed of precipitation catalyst is mounted at the top of the reactor above the path. steam flow (for example, steam does not enter and exit through the top of the catalyst bed).

[00101] The catalyst vents in the fixed bed BRFR and the removable catalyst baskets in the removable catalyst basket BRFR allow for scheduled catalyst replacement, in some embodiments without human entry into the reactor. This can provide a safer operation during the unloading and loading of the catalyst. In addition, facilitating catalyst recovery and replacement in the BRFRs disclosed herein may allow for catalyst replacement in less time (e.g., one-third of the time in embodiments) currently required for typical catalyst unloading and loading for conventional reactors with radial flow. This reduction in time can provide significant savings in downtime costs. The potential for smaller reactors (due to more complete utilization of the catalyst) and the reduction in repair time provided by easier catalyst replacement can reduce capital costs during plant construction and save fixed costs associated with reactor repair. In embodiments of the invention, a fixed bed BRFR provides at least a 5%, 10%, or 12% reduction in catalyst change time compared to a conventional commensurate fixed bed radial flow reactor. In embodiments of the invention, a removable bed BRFR provides at least a 25%, 50%, or 75% reduction in catalyst change time compared to a conventional commensurate fixed bed radial flow reactor. In embodiments of the invention, BRFR provides minimal downtime. For example, in embodiments of the invention, spare baskets may be loaded prior to shutdown.

[00102] As discussed above, the bimodal design proposed herein can be used as a radial flow shield reactor (i.e., BRFGBR), which can eliminate the conventional higher pressure drop shield reactor and/or sulfur converter adsorber. The use of such a shield reactor can further reduce the capital costs associated with a reactor system containing BRFGBR.

[00103] For applications in which catalyst regeneration is desired, the regenerants can be more uniformly distributed across the catalyst beds/zones of the BRFRs disclosed herein compared to conventional radial flow reactors. For example, in regenerations using halides, this more uniform distribution can achieve a lower concentration of halides in the steam stream leaving the reactor during regeneration, which can help protect the material design of the reactor/system from metals. In embodiments of the invention, spent catalyst oxidation can be improved by using the reactor, system, or method described herein. This improvement in spent catalyst oxidation can result in reduced downtime costs and/or reduced likelihood of transporting hazardous waste.

[00104] In embodiments of the invention, the BRFR minimizes cracking by allowing the flow to move to the second bed after deactivation of the catalyst in the start zone.

ADDITIONAL DESCRIPTION

[00105] The specific embodiments of the invention described above are illustrative only, as the invention can be modified and practiced in various but equivalent ways that will be apparent to those skilled in the art who can take advantage of the ideas given in this document. In addition, no restrictions are provided for the details of construction given in this document, other than those described in the following claims. Therefore, it is obvious that the specific illustrative embodiments of the invention described above may be changed or modified, and all such variations are contemplated within the scope and spirit of this invention. Alternative embodiments of the invention that result from combining, integrating and/or eliminating features of the embodiment(s) of the invention are also within the scope of the invention. Although the compositions and methods are described in broader terms "having", "comprising" or "comprising" various components or steps, these compositions and methods may also "essentially consist of" or "consist of" various components and steps. The use of the term "optionally" in relation to any element of the claims means that the specified element is necessary or, alternatively, the specified element is not necessary, and both alternatives are within the scope of the claims.

[00106] The numbers and ranges described above may vary by some amount. In each case where a numeric range with a lower limit and an upper limit is disclosed, any number and any included range falling within that range are specifically disclosed. In particular, each range of values (in the form "from about a to about b" or, equivalently, "from about a to b", or equivalently, "from about a-b") described in this document, should understood as describing each number and range included in the wider range of values. Also, the terms in the claims have their simple, ordinary meaning, unless otherwise expressly and clearly defined by the patentee. In addition, the use in the claims of definitions in the singular in this document refers to one or more than one defined element. If there is any conflict in the use of a word or term in this specification and one or more patent or other documents, then definitions that are consistent with this description shall be adopted.

[00107] Embodiments of the invention disclosed herein include:

[00108] A: A radial flow bimodal reactor comprising: a cylindrical outer casing surrounding at least five cylindrical concentric zones, including at least three annular vapor zones and at least two catalyst zones, with at least two catalyst zones containing an outer catalyst zone and an inner catalyst zone, wherein at least three annular vapor zones comprise an outer annular vapor zone, a middle annular vapor zone, and a central annular vapor zone, wherein the outer catalyst zone is located between the outer annular vapor zone and the middle annular steam zone. zone, and while the inner zone of the catalyst is located between the middle annular steam zone and the Central annular steam zone; as well as a distribution pipeline configured to vertically enter the raw material into the lower end of each of one or two of the at least three annular steam zones and remove the product from the lower end of each of the one or two remaining of the at least three annular steam zones.

[00109] B: A bimodal radial flow guard bed reactor comprising: a cylindrical outer shell surrounding at least five cylindrical concentric zones including at least two annular vapor zones, at least two catalyst zones and a bed separation zone, with wherein at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, wherein at least two annular vapor zones comprise an outer annular vapor zone and a central annular vapor zone, wherein the outer catalyst zone is located between the outer annular vapor zone and the zone layer separation, and while the inner zone of the catalyst is located between the layer separation zone and the Central annular vapor zone; and a distribution conduit configured to vertically introduce feedstock into the lower end of the outer annular steam zone and withdraw product from the lower end of the central annular steam zone.

[00110] C: A radial flow bimodal reactor comprising: a cylindrical outer casing surrounding five cylindrical concentric zones including three annular vapor zones and two catalyst zones, the two catalyst zones comprising an outer catalyst zone and an inner catalyst zone, wherein the inner zone catalyst and the outer zone of the catalyst are made in the form of removable baskets for the catalyst, and while the three annular steam zone contains an outer annular steam zone, the middle annular steam zone and the central annular steam zone, and while the outer zone of the catalyst is located between the outer annular steam zone and the middle an annular vapor zone, wherein the inner catalyst zone is located between the middle annular vapor zone and the central annular vapor zone; as well as a distribution pipeline configured to vertically enter the raw material into the lower end of each of one or two of the three annular steam zones and discharge the product from the lower end of each of the one or two remaining of the three annular steam zones.

[00111] D: A reactor system comprising a bimodal guard bed radial flow reactor described herein, at least one bimodal radial flow reactor with a removable catalyst basket described herein, and at least one bimodal reactor fixed bed radial flow reactor as described herein, wherein the guard bed bimodal radial flow reactor is located upstream of at least one radial flow bimodal reactor with a removable catalyst basket, and wherein at least one radial flow bimodal reactor is with a removable basket for the catalyst is located in front of at least one bimodal fixed bed radial flow reactor.

[00112] Each of embodiments A, B, C, and D may have one or more of the following additional elements: Element 1: wherein the radial flow bimodal reactor is a fixed bed bimodal radial flow reactor in which the inner zone catalyst and the outer zone of the catalyst are made in the form of fixed layers. Element 2: in which the fixed beds are provided with fixed catalyst baskets. Element 3: wherein the fixed catalyst baskets are demarcated by one or more materials selected from the group consisting of Vee- ^Wire® screens, wedge metal screens, and metal screens. Element 4: further comprising at least one opening fluidly connected to the lower end of at least one of the at least two catalyst zones, whereby the catalyst can be removed therefrom. Element 5: having a diameter ranging from about 4 feet (1.22 meters) to about 10 feet (3.05 meters), a height of each of the two catalyst zones ranging from about 10 feet (3.05 meters) to about 30 feet (9.14 meters) or both. Element 6: additionally containing a removable cover attached with the possibility of removal to the upper end of the cylindrical outer casing. Element 7: in which the radial flow bimodal reactor is a radial flow bimodal reactor with a removable catalyst basket, in which the inner catalyst zone and the outer catalyst zone are made as removable catalyst baskets, while the inner catalyst zone is equipped with an internal removable basket for catalyst, and the outer zone of the catalyst is equipped with an external removable basket for the catalyst. Element 8: wherein removable catalyst baskets provide at least a 10% reduction in catalyst change time compared to a conventional fixed bed radial flow reactor of comparable size. Element 9: in which the removable catalyst baskets are removed through the upper end of the cylindrical outer casing. Element 10: further comprising a removable cover removably attached to the top of the cylindrical outer casing. Element 11: further comprising an overlay plate that covers the upper end of the central annular vapor zone, the upper end of the middle annular vapor zone, or both. Element 12: in which the removable cover further comprises a pressure plate that serves as a cover plate. Element 13: further comprising a spacer ring for circumferential alignment configured to restrict flow through the upper end of the outer annular vapor zone. Element 14: additionally containing packing material around the upper annular groove of the outer zone of the catalyst. Element 15: in which the packing contains ceramic fiber insulation in the form of a rope or blanket, or a high temperature fiber spacer. Element 16: wherein the distribution conduit is reversible so that feed can be introduced into the remaining one or two of at least three annular steam zones and product can be diverted from one or two of at least three annular steam zones. Element 17: in which the distribution pipeline further comprises valves, through which the raw material can be introduced into each of the at least two inlets of one or two of the at least three annular steam zones at the same time. Element 18: wherein at least one of the at least two catalyst zones contains a catalyst. Element 19: in which the catalyst is capable of catalyzing an endothermic reaction. Element 20: wherein the catalyst is a reforming catalyst capable of catalyzing the conversion of at least a portion of the convertible hydrocarbons in the feed to aromatic hydrocarbons that are present in the product. Element 21: wherein the reforming catalyst contains at least one Group VIII metal and a zeolite support. Element 22: wherein the Group VIII metal comprises platinum and the zeolite carrier comprises a silica bound L-zeolite. Element 23: wherein the reforming catalyst further comprises at least one halogen. Element 24: wherein the reforming catalyst further contains potassium. Element 25: in which the reforming catalyst contains from about 10% wt. up to about 20% wt. K ₂ O. Element 26: wherein the bimodal radial flow reactor provides longer run time before catalyst change compared to a conventional single modal radial flow reformer operating at equivalent selectivity. Element 27: wherein the radial flow bimodal reactor operates at a lower inlet temperature at the end of the cycle compared to a conventional single modal radial flow reformer operating at equivalent selectivity. Element 28: wherein the inner catalyst zone contains a catalyst that differs from the catalyst in the outer catalyst zone in at least one parameter selected from the group consisting of size, shape, composition, and loading. Element 29: in which the inclusion of another catalyst allows you to control the pressure drop in the inner zone of the catalyst, the outer zone of the catalyst, or both zones. Element 30: in which the inner zone of the catalyst contains a catalyst different from the catalyst in the outer zone of the catalyst. Element 31: in which the inner zone of the catalyst contains a reforming catalyst, a sulfur adsorbing filler, or both. Element 32: in which the outer zone of the catalyst contains a filler that traps iron. Element 33: wherein at least one of the two catalyst zones contains a reforming catalyst capable of catalyzing the conversion of at least a portion of the convertible hydrocarbons in the feed to aromatic hydrocarbons that are present in the product. Element 34: comprising three radial flow bimodal reactors according to claim 8 with a removable catalyst basket and three radial flow fixed bed bimodal reactors according to claim 2. Element 35: wherein the volume of each of the three bimodal radial flow reactors with removable catalyst basket is less than the volume of each of the three fixed bed bimodal radial flow reactors. Element 36: in which at least one bimodal radial flow reactor with a removable catalyst basket and at least one fixed bed bimodal radial flow reactor contain a reforming catalyst capable of catalyzing, in addition, the conversion of at least a portion of the capable of the conversion of hydrocarbons in the feed to aromatic hydrocarbons, which are respectively present in the product.

[00113] While the preferred embodiments of the present invention have been shown and described, modifications may be made by one skilled in the art without deviating from the spirit and ideas of the present invention. The embodiments of the invention described herein are illustrative only and are not intended to be limiting. Numerous variations and modifications of the invention described herein are possible and are within the scope of this invention.

[00114] Numerous other modifications, equivalents, and alternatives will become apparent to those skilled in the art once the invention described above has been fully appreciated. It is intended that the following claims be interpreted to cover all such modifications, equivalents and alternatives, where applicable. Accordingly, the scope of legal protection is not limited to the description set forth above, but is limited only by the following claims, and this scope includes all equivalents of the subject matter in the claims. All claims without exception are included in the description as an embodiment of the present invention. Therefore, the claims are a further description and are in addition to the detailed description of the present invention. The disclosures of all patents, patent applications, and publications cited herein are incorporated herein by reference.

Claims (50)

1. Bimodal radial flow reactor, containing: a cylindrical outer casing surrounding at least five cylindrical concentric zones including at least three annular vapor zones and at least two catalyst zones, wherein at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, and wherein at least at least three annular steam zones comprise an outer annular steam zone, a middle annular steam zone, and a central annular steam zone, with the central annular steam zone extending along the center line of the radial flow bimodal reactor, with the outer catalyst zone located between the outer annular steam zone and a middle annular vapor zone, wherein the inner catalyst zone is located between the middle annular vapor zone and the central annular vapor zone; additionally containing a collector configured to vertically input raw materials into the lower end of each of one or two of at least three annular steam zones and remove the product from the lower end of each of the one or two remaining of at least three annular steam zones. 2. Bimodal radial flow reactor according to claim 1, characterized in that the collector contains a pipeline. 3. The radial flow bimodal reactor according to claim 1, wherein the radial flow bimodal reactor is a fixed bed bimodal radial flow reactor in which the inner catalyst zone and the outer catalyst zone are made as fixed beds. 4. Bimodal radial flow reactor according to claim 3, characterized in that the fixed beds are equipped with fixed baskets for the catalyst. 5. A bimodal radial flow reactor according to claim 1, wherein the bimodal radial flow reactor is a bimodal radial flow reactor with a removable catalyst basket, in which the inner zone of the catalyst and the outer zone of the catalyst are made in the form of removable baskets for the catalyst wherein the inner catalyst zone is equipped with an internal removable catalyst basket and the outer catalyst zone is equipped with an external removable catalyst basket. 6. The radial flow bimodal reactor of claim 5, wherein the removable catalyst baskets are removed through the upper end of the cylindrical outer shell. 7. The radial flow bimodal reactor of claim 1, wherein at least one of the at least two catalyst zones comprises a reforming catalyst capable of catalyzing the conversion of at least a portion of the convertible hydrocarbons in the feed to aromatic hydrocarbons that are present. in the product. 8. Bimodal radial flow reactor according to claim 7, characterized in that the inner catalyst zone contains a catalyst that differs from the catalyst in the outer catalyst zone in at least one parameter selected from the group consisting of size, shape, composition and loading . 9. A bimodal radial flow guard bed reactor comprising: a cylindrical outer casing surrounding at least five cylindrical concentric zones including at least two annular vapor zones, at least two catalyst zones and a bed separation zone, wherein at least at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, wherein at least two annular steam zones comprise an outer annular steam zone and a central annular steam zone, the central annular steam zone extending along the center line of a bimodal radial flow reactor with a protective layer, and while the outer zone of the catalyst is located between the outer annular vapor zone and the separation zone of the layer, and while the internal zone of the catalyst is located between the separation zone of the layer and the central annular vapor zone; additionally containing a collector configured to vertically enter the raw material into the lower end of the outer annular steam zone and remove the product from the lower end of the central annular steam zone. 10. A bimodal radial flow reactor with a protective layer according to claim 9, characterized in that the inner zone of the catalyst and the outer zone of the catalyst are made in the form of removable baskets for the catalyst, while the inner zone of the catalyst is equipped with an internal removable basket for the catalyst, and the outer zone of the catalyst equipped with an external removable basket for the catalyst. 11. A bimodal radial flow reactor with a protective bed according to claim 9, characterized in that at least one of the at least two catalyst zones contains a catalyst capable of catalyzing the conversion of at least a portion of the convertible hydrocarbons in the feed to aromatic hydrocarbons, that are present in the product. 12. Bimodal radial flow reactor, containing: a cylindrical outer casing surrounding five cylindrical concentric zones, including three annular steam zones and two catalyst zones, and two catalyst zones contain an outer catalyst zone and an inner catalyst zone, while the inner catalyst zone and the outer catalyst zone are made in the form of removable catalyst baskets, and wherein the three annular steam zones comprise an outer annular steam zone, a middle annular steam zone, and a central annular steam zone, wherein the central annular steam zone extends along the centerline of the radial flow bimodal reactor, and wherein the outer catalyst zone is located between the outer annular steam zone zone and the middle annular steam zone, and while the inner zone of the catalyst is located between the middle annular steam zone and the Central annular steam zone; additionally containing a collector configured to vertically input raw materials into the lower end of each of one or two of at least three annular steam zones and remove the product from the lower end of each of the one or two remaining of at least three annular steam zones. 13. The radial flow bimodal reactor of claim 12 wherein one of the two catalyst zones contains a reforming catalyst capable of catalyzing the conversion of at least a portion of the convertible hydrocarbons in the feed to aromatics present in the product. 14. A reactor system comprising a bimodal radial flow reactor with a protective bed, at least one bimodal radial flow reactor with a removable catalyst basket, and at least one bimodal fixed bed radial flow reactor, wherein the bimodal radial flow reactor with a protective bed is located before at least one bimodal radial flow reactor with a removable catalyst basket, and at the same time at least one bimodal radial flow reactor with a removable catalyst basket is located before at least one bimodal fixed bed radial flow reactor , wherein at least one bimodal radial flow reactor with removable catalyst basket and at least one bimodal fixed bed radial flow reactor comprises: a cylindrical outer casing surrounding at least five cylindrical concentric zones including at least three annular vapor zones and at least two catalyst zones, wherein at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, and wherein at least at least three annular steam zones comprise an outer annular steam zone, a middle annular steam zone, and a central annular steam zone, with the central annular steam zone extending along the center line of the radial flow bimodal reactor, with the outer catalyst zone located between the outer annular steam zone and a middle annular vapor zone, wherein the inner catalyst zone is located between the middle annular vapor zone and the central annular vapor zone; as well as wherein the inner catalyst zone and the outer catalyst zone in the fixed bed bimodal radial flow reactor are made as fixed beds; and wherein the inner catalyst zone and the outer catalyst zone of at least one bimodal radial flow reactor with a removable catalyst basket are made in the form of removable catalyst baskets, while the inner catalyst zone is equipped with an internal removable catalyst basket, and the outer catalyst zone is equipped with an external removable basket for the catalyst, and while the bimodal reactor with a protective layer with a radial flow contains: a cylindrical outer casing surrounding at least five cylindrical concentric zones, including at least two annular vapor zones, at least two catalyst zones and a bed separation zone, wherein at least two catalyst zones contain an outer catalyst zone and an inner catalyst zone, wherein at least two annular steam zones comprise an outer annular steam zone and a central annular steam zone, wherein the central annular steam zone extends along the center line of the bimodal radial flow reactor with a protective bed, and the outer catalyst zone is located between the outer annular steam zone a bed separation zone and a bed separation zone, wherein the inner catalyst zone is located between the bed separation zone and the central annular vapor zone; wherein each of at least one radial flow bimodal reactor with a removable catalyst basket and at least one fixed bed bimodal radial flow reactor further comprises: a manifold configured to vertically introduce feed into the lower end of the outer annular steam zone and withdrawing product from the lower end of the central annular steam zone; and wherein the bimodal reactor with a radial flow with a protective layer further comprises: a collector configured to vertically enter the raw material into the lower end of the outer annular steam zone and remove the product from the lower end of the central annular steam zone. 15. The reactor system of claim 14, wherein the volume of each of the at least one bimodal radial flow reactor with removable catalyst basket is less than the volume of each of the at least one fixed bed bimodal radial flow reactor. 16. Bimodal radial flow reactor, containing: a cylindrical outer casing surrounding at least five cylindrical concentric zones including at least three annular vapor zones and at least two catalyst zones, wherein at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, and wherein at least at least three annular steam zones comprise an outer annular steam zone, a middle annular steam zone, and a central annular steam zone, with the central annular steam zone extending along the center line of the radial flow bimodal reactor, with the outer catalyst zone located between the outer annular steam zone and a middle annular vapor zone, wherein the inner catalyst zone is located between the middle annular vapor zone and the central annular vapor zone; a removable cover configured to be fixedly attached to the top of the cylindrical outer casing to seal the top of the radial flow bimodal reactor; and an overlay plate that covers the upper end of the central annular vapor zone and/or the upper end of the middle annular vapor zone, wherein the removable lid further comprises a pressure plate which serves as an overlay plate and allows expansion of the catalyst in the outer catalyst zone, the inner catalyst zone, or both the outer catalyst zone and the inner catalyst zone. 17. The radial flow bimodal reactor of claim 16, wherein the inner catalyst zone and the outer catalyst zone are formed as catalyst baskets, and the pressure plate allows expansion of the catalyst in the catalyst baskets. 18. Bimodal radial flow reactor, containing: a cylindrical outer casing surrounding at least five cylindrical concentric zones including at least three annular vapor zones and at least two catalyst zones, wherein at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone, and wherein at least at least three annular steam zones comprise an outer annular steam zone, a middle annular steam zone, and a central annular steam zone, with the central annular steam zone extending along the center line of the radial flow bimodal reactor, with the outer catalyst zone located between the outer annular steam zone and a middle annular vapor zone, wherein the inner catalyst zone is located between the middle annular vapor zone and the central annular vapor zone; and a removable lid configured to be fixedly attached to the top of the cylindrical outer casing to seal the top of the bimodal radial flow reactor, the removable lid comprising a pressure pad that aligns with the top of the central annular steam zone when the bimodal radial flow reactor is closed, the pressure pad a plate that aligns with the top of the middle annular steam zone when the bimodal radial flow reactor is closed, or a pressure pad that aligns with the top of the central annular steam zone and the top of the middle annular steam zone when the bimodal radial flow reactor is closed. 19. The radial flow bimodal reactor according to claim 18, wherein the radial flow bimodal reactor is a fixed bed bimodal radial flow reactor, wherein the inner catalyst zone and the outer catalyst zone are formed as fixed beds. 20. Bimodal radial flow reactor according to claim 19, characterized in that the fixed beds are provided with fixed baskets for the catalyst. 21. The radial flow bimodal reactor of claim 20 wherein the fixed catalyst baskets are demarcated by one or more materials selected from the group consisting of wedge wire screens. 22. The radial flow bimodal reactor of claim 19, further comprising at least one opening fluidly connected to the lower end of at least one of the at least two catalyst zones, whereby the catalyst can be removed therefrom. 23. Bimodal radial flow reactor according to claim 19, characterized in that the bimodal radial flow reactor is a bimodal radial flow reactor with removable baskets, while the inner catalyst zone and the outer catalyst zone are made as removable baskets, and the inner catalyst zone is provided with an inner catalyst basket, and the outer zone of the catalyst is provided with an external catalyst basket. 24. The bimodal radial flow reactor of claim 23 wherein the removable baskets provide at least a 10% reduction in catalyst change time compared to a conventional fixed bed radial flow reactor of comparable size. 25. Bimodal radial flow reactor according to claim 23, characterized in that the removable baskets are removed through the upper end of the cylindrical outer casing. 26. The radial flow bimodal reactor of claim 19, wherein the outer catalyst zone, the inner catalyst zone, or both the outer catalyst zone and the inner catalyst zone have a diameter ranging from about 0.5 feet (0.15 meters) to about 2 feet (0.61 meters) and/or a height of about 5 feet (1.52 meters) to about 50 feet (15.24 meters). 27. The radial flow bimodal reactor according to claim 19, further comprising a manifold configured to vertically introduce feed into the lower end of each of one or two of at least three annular steam zones and remove product from the lower end of each of the one or two remaining of at least three annular steam zones. 28. The radial flow bimodal reactor according to claim 27, characterized in that the manifold is configured to reverse the direction of the process flow so that feed can be introduced into the remaining one or two of the at least three free steam zones and can be withdraw product from one or two of the at least three free steam zones. 29. The radial flow bimodal reactor of claim 19, wherein at least one of the at least two catalyst zones contains a catalyst. 30. A bimodal radial flow reactor according to claim 29, characterized in that the catalyst is capable of catalyzing an endothermic reaction. 31. The radial flow bimodal reactor of claim 30, wherein the reforming catalyst is capable of catalyzing the conversion of at least a portion of the convertible hydrocarbons in the feed to aromatic hydrocarbons that are present in the product. 32. The radial flow bimodal reactor of claim 31, wherein the radial flow bimodal reactor provides a longer run time before catalyst change compared to a conventional single modal radial flow reformer operating at equivalent selectivity, and/or in that the bimodal radial flow reactor operates at a lower inlet temperature at the end of the run compared to a conventional single modal radial flow reformer operating at equivalent selectivity. 33. Bimodal radial flow reactor according to claim 29, characterized in that the inner catalyst zone contains a catalyst that differs from the catalyst in the outer catalyst zone in at least one parameter selected from the group consisting of size, shape, composition and loading . 34. The radial flow bimodal reactor of claim 31, wherein the reforming catalyst comprises at least one Group VIII metal and a zeolite support. 35. Bimodal radial flow reactor according to claim 19, characterized in that the outer zone of the catalyst contains a filler that traps iron.

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