WO2018172889A1

WO2018172889A1 - Systems and methods for uprating dehydrogenation reactors

Info

Publication number: WO2018172889A1
Application number: PCT/IB2018/051720
Authority: WO
Inventors: Vijay Dinkar BODAS; Sultan Al-Otaibe; Guillermo LEAL; Mohammed Bismillah ANSARI
Original assignee: Sabic Global Technologies B.V.
Priority date: 2017-03-20
Filing date: 2018-03-14
Publication date: 2018-09-27
Also published as: SA519410056B1

Abstract

A catalytic reactor is disclosed. The catalytic reactor includes one or more nonporous covers configured to cover a portion of each of the plurality of catalyst beds so that when the gas feed flows through the feed inlet into the catalytic reactor, the gas feed does not enter the plurality of catalyst beds at a section of each of the catalyst beds closest to the feed inlet. Instead, the gas feed enters each catalyst bed at another section of each of the catalyst beds.

Description

SYSTEMS AND METHODS FOR UPRATING DEHYDROGENATION REACTORS CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Patent

Application No. 62/473,964, filed March 20, 2017, which is hereby incorporated by reference in its entirety.

FIELD OF INVENTION

[0002] The present invention generally relates to equipment used in carrying out chemical reactions in industrial processes. More specifically, the present invention relates to a fixed bed reactor for use in dehydrogenating hydrocarbons.

BACKGROUND OF THE INVENTION

[0003] Olefins such as propylene and ethylene are important petroleum building blocks for a wide variety of polymers and intermediaries. Olefins have a double bond and one method of producing olefins is to dehydrogenate other hydrocarbons such as paraffins to create a double bond and thereby form olefins. Typically, the dehydrogenation reaction takes place in the presence of a catalyst in a dehydrogenation reactor. For example, there are olefin plants designed to catalytically dehydrogenate propane, isobutane, 1-butene, and isopentane.

[0004] Generally, catalytic dehydrogenation reactors are down-flow single bed reactors. For example, US Patent No. 2,915,375 discloses a single bed dehydrogenation reactor design currently practiced in the industry. Conventional fixed bed reactors sometimes include an inlet distributor that has a stack of circular or oval plates with a large central hole and a single multi-hole plate at the bottom of the inlet distributor.

[0005] Demand for olefins is increasing. However, operating olefin reactors in existing plants at feed rates in excess of the plants' design feed rates can lead to flow maldistribution and associated operating problems. Further, a potential solution for meeting the increased demand is scaling up the olefin plant by installing parallel reactors. But this solution would require large capital expenditure. BRIEF SUMMARY OF THE INVENTION

[0006] A discovery has been made of a fixed bed catalytic reactor that flows feedstock through catalyst in the reactor in a manner that maximizes contact between the feedstock and the catalyst in the limited space of the reactor. The discovered fixed bed catalytic reactor, according to embodiments of the invention, splits the flow of the feedstock and channels the feedstock to flow through catalyst beds at an angle to the initial flow of the feedstock into the reactor to effect enhanced flow distribution.

[0007] Embodiments of the invention include a catalytic reactor that includes one or more walls and a feed inlet adapted to channel flow of a gas feed into the catalytic reactor. The catalytic reactor may further include a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end. The catalytic reactor may further include one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds and configured to cover a portion comprising the first end of each of the plurality of catalyst beds so that feed gas entering the catalytic reactor is substantially or completely prevented from entering each catalyst bed at the first end.

[0008] Embodiments of the invention include a catalytic reactor that includes one or more walls that forms a cylindrical vessel. The catalytic reactor may include two catalyst beds disposed within the cylindrical vessel and a feed inlet adapted to channel flow of a gas feed into the catalytic reactor. The catalytic reactor may further include a nonporous cover configured to cover a portion of each of the two catalyst beds so that when the gas feed flows through the feed inlet into the catalytic reactor, the gas feed does not enter the two catalyst beds at a section of each of the two catalyst beds closest to the feed inlet and does not enter the two catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet. Instead, the gas feed enters each catalyst bed at another section of each of the catalyst beds in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet. The catalytic reactor may also include a central chamber between the two catalyst beds adapted to receive gas flowing from the catalyst beds. Further yet, the catalytic reactor may include a manifold below the catalyst bed. The manifold is in fluid communication with the central chamber. The manifold is also in fluid communication with one or more outlets configured to flow one or more gases from the manifold. [0009] Embodiments of the invention include a method of dehydrogenating hydrocarbon. The method includes flowing a gas feed into a catalytic reactor through a feed inlet adapted to channel flow of a gas feed into the catalytic reactor. The catalytic reactor can have one or more walls and a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end. The method may further include channeling the gas feed entering the catalytic reactor so that it is substantially or completely prevented from entering each catalyst bed at the first end, the channeling performed by one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds.

[0010] Embodiments of the invention include a method of retrofitting a catalytic reactor. The method includes providing a catalytic reactor that has one or more walls, a feed inlet adapted to channel flow of a gas feed into the catalytic reactor, and a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet; a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end. The method may further include adding one or more nonporous covers between the feed inlet and the plurality of catalyst beds so that the one or more nonporous covers cover a portion comprising the first end of each of the plurality of catalyst beds and that feed gas entering the catalytic reactor is substantially or completely prevented from entering each catalyst bed at the first end.

[0011] The following includes definitions of various terms and phrases used throughout this specification.

[0012] The terms "about" or "approximately" are defined as being close to as understood by one of ordinary skill in the art. In one non-limiting embodiment the terms are defined to be within 10%, preferably, within 5%, more preferably, within 1%, and most preferably, within 0.5%.

[0013] The terms "wt.%," "vol.%" or "mol.%" refer to a weight, volume, or molar percentage of a component, respectively, based on the total weight, the total volume, or the total moles of material that include the component. In a non-limiting example, 10 moles of component in 100 moles of the material is 10 mol.% of component. [0014] The term "substantially" and its variations are defined to include ranges within

10%, within 5%, within 1%, or within 0.5%.

[0015] The terms "inhibiting" or "reducing" or "preventing" or "avoiding" or any variation of these terms, when used in the claims and/or the specification, include any measurable decrease or complete inhibition to achieve a desired result.

[0016] The term "effective," as that term is used in the specification and/or claims, means adequate to accomplish a desired, expected, or intended result.

[0017] The use of the words "a" or "an" when used in conjunction with the term

"comprising," "including," "containing," or "having" in the claims or the specification may mean "one," but it is also consistent with the meaning of "one or more," "at least one," and "one or more than one."

[0018] The words "comprising" (and any form of comprising, such as "comprise" and

"comprises"), "having" (and any form of having, such as "have" and "has"), "including" (and any form of including, such as "includes" and "include") or "containing" (and any form of containing, such as "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0019] The process of the present invention can "comprise," "consist essentially of," or "consist of particular ingredients, components, compositions, etc., disclosed throughout the specification.

[0020] In the context of the present invention, at least the following twenty embodiments are provided. Embodiment 1 relates to a catalytic reactor. The catalytic reactor includes one or more walls; a feed inlet adapted to channel flow of a gas feed into the catalytic reactor; a plurality of catalyst beds disposed within the one or more walls, each catalyst bed including a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end; one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds and configured to cover a portion including the first end of each of the plurality of catalyst beds so that feed gas entering the catalytic reactor is substantially prevented from entering each catalyst bed at the first end. Embodiment 2 relates to the catalytic reactor of embodiment 1, wherein two catalyst beds are disposed within the one or more walls. Embodiment 3 relates to the catalytic reactor of embodiment 2 wherein the catalytic reactor has one nonporous cover configured to cover a portion of each of the two catalyst beds. Embodiment 4 relates to the catalytic reactor of any of embodiments 2 and 3, wherein the gas feed does not enter the two catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet, instead, the gas feed enters each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet. Embodiment 5 relates to the catalytic reactor of any of embodiments 1 to 4, wherein the catalytic reactor comprises a cylindrical vessel. Embodiment 6 relates to the catalytic reactor of any of embodiments 2 to 5, further comprising a central chamber between the two catalyst beds adapted to receive gas flowing from the catalyst beds. Embodiment 7 relates to the catalytic reactor of embodiment 6, further comprising a manifold below the catalyst beds and in fluid communication with the central chamber. Embodiment 8 relates to the catalytic reactor of embodiment 7, further including one or more outlets in fluid communication with the manifold configured to flow one or more gases from the manifold. Embodiment 9 relates to the catalytic reactor of embodiment 8, wherein the one or more gases comprise air when a decarburizing cycle is in operation. Embodiment 10 relates to the catalytic reactor of embodiment 8, wherein the one or more gases comprise hydrocarbon gas when a dehydrogenation cycle is in operation. Embodiment 11 relates to the catalytic reactor of any of embodiments 1 to 10, wherein the one or more nonporous covers comprises a refractory arch roof shroud. Embodiment 12 relates to the catalytic reactor of any of embodiments 1 to 10, wherein the one or more nonporous covers comprises an SAE 310S stainless steel curved metal plate. Embodiment 13 relates to the catalytic reactor of any of embodiments 1 to 10, wherein the one or more nonporous covers comprises an SAE 304L stainless steel curved plate with a polymeric coating/painting. Embodiment 14 relates to the catalytic reactor of any of embodiments 1 to 13, wherein the one or more nonporous covers channel the flow of gas feed along side walls prior to the gas feed entering the catalyst beds.

[0021] Embodiment 15 relates to a method of dehydrogenating hydrocarbon, the method includes the step of flowing a gas feed into a catalytic reactor through a feed inlet adapted to channel flow of a gas feed into the catalytic reactor, the catalytic reactor having one or more walls and a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end; channeling the gas feed entering the catalytic reactor so that it is substantially prevented from entering each catalyst bed at the first end, the channeling performed by one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds. Embodiment 16 relates to the method of embodiment 15, further including the step of flowing the gas feed so that the gas feed does not enter the plurality of catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet, instead, the gas feed enters each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet. Embodiment 17 relates to the method of embodiment 16, further including the step on flowing gas product from the catalyst beds to a central chamber between the plurality of catalyst beds, the central chamber adapted to receive the gas product flowing from the catalyst beds. Embodiment 18 relates to the method of embodiment 17, further including flowing the gas product through a manifold below the catalyst bed and in fluid communication with the central chamber.

[0022] Embodiment 19 relates to a method of retrofitting a catalytic reactor. The method of embodiment 19 includes the steps of providing a catalytic reactor that includes one or more walls; a feed inlet adapted to channel flow of a gas feed into the catalytic reactor; a plurality of catalyst beds disposed within the one or more walls, each catalyst bed includes a first end disposed near the feed inlet; a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end; adding one or more nonporous covers between the feed inlet and the plurality of catalyst beds so that the one or more nonporous covers cover a portion including the first end of each of the plurality of catalyst beds and that feed gas entering the catalytic reactor is substantially prevented from entering each catalyst bed at the first end. Embodiment 20 relates to the method of embodiment 19, wherein the one or more nonporous covers and the one or more walls are adapted to flow the gas feed to enter each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet.

[0023] Other objects, features and advantages of the present invention will become apparent from the following figures, detailed description, and examples. It should be understood, however, that the figures, detailed description, and examples, while indicating specific embodiments of the invention, are given by way of illustration only and are not meant to be limiting. Additionally, it is contemplated that changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. In further embodiments, features from specific embodiments may be combined with features from other embodiments. For example, features from one embodiment may be combined with features from any of the other embodiments. In further embodiments, additional features may be added to the specific embodiments described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] For a more complete understanding, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

[0025] FIGS. 1A and IB show front views of a fixed bed reactor for dehydrogenating hydrocarbons, according to embodiments of the invention;

[0026] FIG. 2 shows a side view of a fixed bed reactor for dehydrogenating hydrocarbons, according to embodiments of the invention;

[0027] FIG. 3 shows a method of dehydrogenating hydrocarbons in a fixed bed reactor, according to embodiments of the invention; and

[0028] FIG. 4 shows a method of retrofitting a fixed bed reactor for dehydrogenating hydrocarbons, according to embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0029] A discovery has been made of a fixed bed catalytic reactor that flows feedstock through catalyst in the reactor in a manner that maximizes contact between the feedstock and the catalyst in the limited space of the reactor. The discovered fixed bed catalytic reactor, according to embodiments of the invention, splits the flow of the feedstock and channels the feedstock to flow through catalyst beds of the reactor at an angle to the initial flow of the feedstock into the reactor to effect enhanced flow distribution. The cross sectional flow area for the incoming feedstock is greater in a fixed bed reactor having a shell of a particular geometric volume and configured according to embodiments of the invention as compared with a conventional fixed bed reactor having the same geometric volume. Thus, new fixed bed catalytic reactors configured according to embodiments of the invention will have a higher cross sectional flow area rating than same sized conventional units. Further, conventional reactors may be uprated by modifying them to meet the configurations of embodiments of the invention disclosed herein. In this way, for conventional reactors in operation, a redesigning/retrofitting according to embodiments of the invention can increase the reactors' throughput without leading lump formation. Thus, the redesigning/retrofitting can result in longer catalyst life.

[0030] For dehydrogenation reactors, if heat absorbed by the endothermic reaction is kept constant and the catalyst bed volume is reduced, the average bed temperature will increase to deliver the same heat as the original catalyst bed volume did. In a given reactor vessel, therefore, if reactant flow is increased with the expectation of getting more product, the kinetics requires the catalyst bed cross sectional area to be increased. This keeps contact time the same (catalyst bed length/fluid velocity) as at lower throughput flow. An increase in cross sectional area increases heat storage volume of the catalyst bed and keeps kinetic contact time constant. Scaling up of a Houdry reactor is thus increasing its inlet cross sectional area and keeping contact time the same. To implement this requires capital investment in parallel reactors.

[0031] In most dehydrogenating plants, the throughput is increased along with the vertical height of the catalyst bed, thereby altering the contact time. But this increase is severely constrained because of lack of space in the reactor and the ease with which the feed can be increased in these reactors, up to as much as 50% over design values. Towards the end of dehydrogenation batch cycle, this configuration causes overheating of the extra-added portion of catalyst bed length where there is no reactant coming in, eventually leading to "Houdry lump, a stalagmite like crude ruby" formation. Yet unsurprisingly, a reduction of catalyst bed height leads to increased average solid temperature requirements and increased reactant gas injection to keep the rate of reaction constant. This paradox can only be resolved if the cross sectional flow area of the catalyst bed is increased as throughput rises. The industry is unable to do this because the reactor geometry and volume is fixed, even though operating economics suggests maximization of feedstock and throughput.

[0032] There is also a need to increase the design throughput rating of existing reactor vessels without resorting to a redesign of mechanical details. The complete redesign at higher size requires extended length of time and trials, especially where a near artwork style internal refractory lining is involved.

[0033] The presently proposed reactor design brings about an innovative change in internal flow pattern and resolves the aforementioned issues. After implementing embodiments of the invention in existing operating plants, the lump formation reduces and the reactor vessel becomes capable of higher throughput. Higher nameplate throughput rating obtained from existing vessel design in a new plant is therefore obtainable. Embodiments of the invention can also save capital investments because when the embodiments are implemented in a plant the plant may require a fewer number of parallel reactors for a given nameplate rating.

[0034] FIGS. 1A and IB show fixed bed reactor 10 for dehydrogenating hydrocarbons, according to embodiments of the invention. FIGS. 1A and IB show a front view of fixed bed reactor 10. Fixed bed reactor 10 is a catalytic reactor that includes catalyst bed 101 and catalyst bed 102 disposed within wall 100. In embodiments of the invention, catalyst bed 101 and catalyst bed 102 are two equally sized rectangular beds on either side of fixed bed reactor 10. FIGS. 1A and IB show the front view of wall 100 being circular as fixed bed reactor 10 has a cylindrical shape. It should be noted however, that in embodiments of the invention, fixed bed reactor 10 may include one or more walls and may be of other shapes such as horizontal cylinder, vertical cylinder tank, rectangle tank, horizontal oval tank, vertical oval tank, horizontal capsule tank, and vertical capsule tank.

[0035] Fixed bed reactor 10 includes feed inlet 103, which is adapted to split gas feed

109 and channel flow of gas feed 109 into fixed bed reactor 10. Fixed bed reactor 10 further includes cover 104 (a nonporous cover), which is configured to cover a section (section 101 A and section 102A) of each of catalyst bed 101 and catalyst bed 102, respectively. In this way, when gas feed 109 flows through feed inlet 103 into fixed bed reactor 10, gas feed 109 does not enter catalyst bed 101 and catalyst bed 102 at section 101 A and section 102 A, respectively, which are sections of each of catalyst bed 101 and catalyst bed 102 closest to feed inlet 103. Instead, gas feed 109 enters catalyst bed 101 and catalyst bed 102 at other sections, namely section 101B and section 102B. In embodiments of the invention, the section of a catalyst bed (e.g., of catalyst bed 101 or catalyst bed 102) that is closest to the feed inlet (e.g., feed inlet 103) is the l/lO¹¹¹ volume of the catalyst bed (e.g., section 101 A and section 102A) that is closest to the feed inlet (e.g., feed inlet 103). In embodiments of the invention, fixed bed reactor 10 does not include an inlet distributor. As noted above, cover 104 is used to channel the flow of gas feed 109 within fixed bed reactor 10. Cover 104 may be made of metal such as stainless steel and carbon steels, ceramic material, and combinations thereof. In embodiments of the invention, cover 104 may be one of the list consisting of: a refractory arch roof shroud, a SAE 310S stainless steel or compatible curved metal plate, a SAE 304L stainless steel curved plate with a polymeric coating/painting that reduces deterioration due to carburizing and cyclically oxidizing and reducing environments.

[0036] Because cover 104 covers the upper sections of catalyst bed 101 and catalyst bed 102 (section 101 A and section 102 A), after gas feed 109 enters fixed bed reactor 10, gas feed 109 does not enter catalyst bed 101 and catalyst bed 102 in a direction parallel to direction of flow of gas feed 109 through feed inlet 103. Instead, gas feed 109 enters catalyst bed 101 and catalyst bed 102 in a direction lateral (shown by arrows 106) and/or slanted (shown by arrows 110) to the direction of flow of gas feed (109) through feed inlet 103. In other words, gas feed 109 is moved to wall 100 by cover 104 (an impervious non porous refractory arch roof shroud) covering the top of catalyst bed 101 and catalyst bed 102. In embodiments of the invention, gas feed 109 enters catalyst bed 101 and catalyst bed 102 through bricks that have downward sloped slots to prevent escape of catalyst particles.

[0037] In embodiments of the invention, gas feed 109 flows into catalyst bed 101 and catalyst bed 102, as described above, where gas feed 109 contacts catalyst of catalyst bed 101 and catalyst bed 102, which causes hydrocarbons of gas feed 109 (when gas feed 109 includes hydrocarbons such as paraffins) to dehydrogenate and form gas product 111. Catalyst bed 101 and catalyst bed 102 are adapted so that gas product 111 flows into central chamber 107. Central chamber 107 is located between catalyst bed 101 and catalyst bed 102. In this way, central chamber 107 is adapted to receive gas product 111 flowing from catalyst bed 101 and catalyst bed 102.

[0038] Fixed bed reactor 10 may also include manifold 108. As shown in FIG. 1, in embodiments of the invention, manifold 108 is located below catalyst bed 101 and catalyst bed 102 and is in fluid communication with central chamber 107. In embodiments of the invention, fixed bed reactor 10 further includes one or more outlets 112 in fluid communication with manifold 108. Outlets 112 are configured to flow one or more gases from manifold 108. In embodiments of the invention, fixed bed reactor 10 has a first outlet 112 for air and a second outlet 112 for hydrocarbon exit, each used in alternating cycles of dehydrogenating and decarburizing.

[0039] Fixed bed reactor 10 operates in cycles. In a first cycle, gas feed 109 is a gas that includes hydrocarbons to be dehydrogenated such as propane, isobutane, 1-butene, and isopentane. When gas feed 109 is hydrogenated, it forms gas product 111, which may include one or more olefins such as ethylene and propylene. The dehydrogenation process causes carburization in fixed reactor 10. Carburization is the deposit of carbon in the reactor for example, on the catalyst, which impairs the performance of the catalyst. Thus, to keep the dehydrogenation process operating efficiently, the deposited carbon is removed in a second cycle. In the second cycle, gas feed 109 is air which reacts with the carbon to form carbon oxides (e.g., carbon dioxide (CO2)). Thus, the gas product in the second cycle is a gas that includes carbon oxides.

[0040] FIG. 1A shows fixed bed reactor 10 in an orientation where gas feed 109 enters fixed bed reactor 10 vertically downwards. In this way, cover 104 covers the top of catalyst bed 101 and catalyst bed 102 (section 101 A and section 102 A) when the flow of gas feed 109, entering fixed bed reactor 10 is vertically downward and cover 104 channels gas feed 109 to flow horizontally (shown by arrows 106) into, or at an acute angle (shown by arrows 110) into, catalyst bed 101 and catalyst bed 102. In embodiments of the invention, cover 104 along with wall 100 cooperate to channel gas feed 109 to flow horizontally (shown by arrows 106) into, or at an acute angle (shown by arrows 110) into, catalyst bed 101 and catalyst bed 102. In this way, cover 104 channels the flow of gas feed 109 along wall 100 prior to feed 109 entering catalyst bed 101 and catalyst bed 102.

[0041] FIG. IB shows fixed bed reactor 10 in an orientation where gas feed 109 enters fixed bed reactor 10 laterally. In this way, cover 104 covers the side of catalyst bed 101 and catalyst bed 102 (section 101 A and section 102 A) when the flow of gas feed 109, entering fixed bed reactor 10 is lateral and cover 104 channels gas feed 109 to flow vertically (shown by arrows 106') into, or at an acute angle (shown by arrows 110') into, catalyst bed 101 and catalyst bed 102. In embodiments of the invention, cover 104 along with wall 100 cooperate to channel gas feed 109 to flow vertically (shown by arrows 106') into, or at an acute angle (shown by arrows 110') into, catalyst bed 101 and catalyst bed 102. In this way, cover 104 channels the flow of gas feed 109 along wall 100 prior to gas feed 109 entering catalyst bed 101 and catalyst bed 102.

[0042] FIG. 2 shows a side view of a fixed bed reactor 10 for dehydrogenating hydrocarbons, according to embodiments of the invention. FIG. 3 shows method 30 for dehydrogenating hydrocarbons in a fixed bed reactor, according to embodiments of the invention. Method 30 may be implemented using fixed bed reactor 10. Method 30 may begin at block 300, which may include flowing a gas feed such as gas feed 109 into a catalytic reactor (e.g., fixed bed reactor 10) through a feed inlet such as feed inlet 103. The catalytic reactor may have a plurality of catalyst beds such as catalyst bed 101 and catalyst bed 102, shown in FIG. 1. As implemented by fixed bed reactor 10, method 30 may include, at block 301, channeling gas feed 109 away from a section of each of catalyst bed 101 and catalyst bed 102 closest to feed inlet 103 (section 101 A and section 102 A). In embodiments of the invention, as implemented with fixed bed reactor 10, the channeling is carried out at least by cover 104, which is configured to cover a portion of each of the plurality of catalyst bed 101 and catalyst bed 102, specifically section 101 A and section 102 A. At block 302, method 30 involves flowing gas feed 109 so that it enters each of catalyst bed 101 and catalyst bed 102, not at section 101A and section 102A, but at another section (section 101B and section 102B) of each of catalyst bed 101 and catalyst bed 102. As gas feed 109 enters each of catalyst bed 101 and catalyst bed 102, it does so in a direction that is not parallel to direction of flow of gas feed 109 through feed inlet 103. Instead, gas feed 109 enters each of catalyst bed 101 and catalyst bed 102 in a direction lateral (e.g., shown by arrows 106) and/or slanted (e.g., shown by arrows 1 10) to the direction of flow of gas feed 109 through feed inlet 103.

[0043] Block 303 involves contacting hydrocarbons of gas feed 109 with catalyst of catalyst bed 101 and catalyst bed 102 under reaction conditions sufficient to produce gas product 1 1 1. When gas feed 109 is hydrocarbon, gas product 1 1 1 may include olefins such as ethylene and propylene. When gas feed 109 is air, gas product 1 1 1 may include carbon oxides such as carbon dioxide (CO2).

[0044] At block 304, method 30 may involve flowing gas product 1 1 1 from catalyst bed 101 and catalyst bed 102 to central chamber 107, which is between catalyst bed 101 and catalyst bed 102 and is adapted to receive gas product 1 1 1 flowing from catalyst bed 101 and catalyst bed 102. Block 305 may include flowing gas product 1 1 1, e.g., through a refractory floor, to manifold 108. As shown in FIG. 1, manifold 108 is located below catalyst bed 101 and catalyst bed 102 and is in fluid communication with central chamber 107. At block 306, gas product 1 1 1 is discharged from fixed bed reactor 10 through outlet 1 12.

[0045] FIG. 4 shows method 40 for retrofitting a fixed bed reactor for dehydrogenating hydrocarbons, according to embodiments of the invention. Method 40 may include, at block 400, identifying a catalytic reactor suitable for retrofitting according to embodiments of the invention. Such a catalytic reactor may include one or more walls, a plurality of catalyst beds disposed within the one or more walls, and a feed inlet adapted to channel flow of a gas feed into the catalytic reactor. Method 40 may further include, at block 401, adding one or more nonporous covers to the catalytic reactor. The one or more nonporous covers are configured to cover a portion of each of the plurality of catalyst beds so that when the gas feed flows through the feed inlet into the catalytic reactor, the gas feed does not enter the plurality of catalyst beds at a section of each of the catalyst beds closest to the feed inlet. Instead, the gas feed enters each catalyst bed at another section of each of the catalyst beds. In embodiments of the invention, the one or more non porous covers and the one or more walls are adapted to flow the gas feed so that the gas feed does not enter the plurality of catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet. Instead, the gas feed enters each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet.

[0046] Embodiments of the invention can achieve increased gas inlet cross sectional area of flow by utilizing nearly the entire bed diameter while requiring minimum space for flow redistribution at inlet. Embodiments of the invention can achieve up to 40% higher design rating for a vessel configured as described herein as compared with a vessel with the same geometry and volume in conventional reactors in standard propane, isobutane, isopentane, and butene-1 dehydrogenation service. Compared to single bed in single vessel design, the design according to embodiments of the invention can increase catalyst volume by 41% and increase the gas flow area by 40%. Typical total gas flow area through both the beds combined is about 117.65 m² and catalyst bed exit flow area remains largely similar.

[0047] Although embodiments of the present invention have been described with reference to blocks of FIG. 3 and FIG. 4, it should be appreciated that operation of the present invention is not limited to the particular blocks and/or the particular order of the blocks illustrated in FIG. 3 and FIG. 4. Accordingly, embodiments of the invention may provide functionality as described herein using various blocks in a sequence different than that of FIG. 3 and FIG. 4.

[0048] In the context of the present invention, embodiments 1-20 are described.

Embodiment 1 is a catalytic reactor. The catalytic reactor includes one or more walls and a feed inlet adapted to channel flow of a gas feed into the catalytic reactor. The catalytic reactor also includes a plurality of catalyst beds disposed within the one or more walls, each catalyst bed having a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end. The catalytic reactor also includes one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds and configured to cover a portion including the first end of each of the plurality of catalyst beds so that feed gas entering the catalytic reactor is substantially prevented from entering each catalyst bed at the first end. Embodiment 2 is the catalytic reactor of embodiment 1, wherein two catalyst beds are disposed within the one or more walls. Embodiment 3 is the catalytic reactor of embodiment 2 wherein the catalytic reactor has one nonporous cover configured to cover a portion of each of the two catalyst beds. Embodiment 4 is the catalytic reactor of either of embodiments 2 or 3, wherein the gas feed does not enter the two catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet, instead, the gas feed enters each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet. Embodiment 5 is the catalytic reactor of any of embodiments 1 to 4, wherein the catalytic reactor comprises a cylindrical vessel. Embodiment 6 is the catalytic reactor of any of embodiments 2 to 5, further including a central chamber between the two catalyst beds adapted to receive gas flowing from the catalyst beds. Embodiment 7 is the catalytic reactor of embodiment 6, further including a manifold below the catalyst beds and in fluid communication with the central chamber. Embodiment 8 is the catalytic reactor of embodiment 7, further including one or more outlets in fluid communication with the manifold configured to flow one or more gases from the manifold. Embodiment 9 is the catalytic reactor of embodiment 8, wherein the one or more gases include air when a decarburizing cycle is in operation. Embodiment 10 is the catalytic reactor of embodiment 8, wherein the one or more gases include hydrocarbon gas when a dehydrogenation cycle is in operation. Embodiment 11 is the catalytic reactor of any of embodiments 1 to 10, wherein the one or more nonporous covers includes a refractory arch roof shroud. Embodiment 12 is the catalytic reactor of any of embodiments 1 to 10, wherein the one or more nonporous covers includes an SAE 310S stainless steel curved metal plate. Embodiment 13 is the catalytic reactor of any of embodiments 1 to 10, wherein the one or more nonporous covers includes an SAE 304L stainless steel curved plate with a polymeric coating/painting. Embodiment 14 is the catalytic reactor of any of embodiments 1 to 13, wherein the one or more nonporous covers channel the flow of gas feed along side walls prior to the gas feed entering the catalyst beds. [0049] Embodiment 15 is a method of dehydrogenating hydrocarbon. The method includes flowing a gas feed into a catalytic reactor through a feed inlet adapted to channel flow of a gas feed into the catalytic reactor, the catalytic reactor having one or more walls and a plurality of catalyst beds disposed within the one or more walls, each catalyst bed including a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end. The method of dehydrogenating hydrocarbon also includes channeling the gas feed entering the catalytic reactor so that it is substantially prevented from entering each catalyst bed at the first end, the channeling performed by one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds. Embodiment 16 is the method of embodiment 15, further including flowing the gas feed so that the gas feed does not enter the plurality of catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet, instead, the gas feed enters each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet. Embodiment 17 is the method of embodiment 16, further including flowing gas product from the catalyst beds to a central chamber between the plurality of catalyst beds, the central chamber adapted to receive the gas product flowing from the catalyst beds. Embodiment 18 is the method of embodiment 17, further including flowing the gas product through a manifold below the catalyst bed and in fluid communication with the central chamber.

[0050] Embodiment 19 is a method of retrofitting a catalytic reactor. The method includes providing a catalytic reactor that includes one or more walls, a feed inlet adapted to channel flow of a gas feed into the catalytic reactor. The catalytic reactor also includes a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end. The method of retrofitting a catalytic reactor includes adding one or more nonporous covers between the feed inlet and the plurality of catalyst beds so that the one or more nonporous covers cover a portion including the first end of each of the plurality of catalyst beds and that feed gas entering the catalytic reactor is substantially prevented from entering each catalyst bed at the first end. Embodiment 20 is the method of embodiment 19, wherein the one or more nonporous covers and the one or more walls are adapted to flow the gas feed to enter each catalyst beds in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet. [0051] Although embodiments of the present application and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the embodiments as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the above disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims

A catalytic reactor comprising:

one or more walls;

a feed inlet adapted to channel flow of a gas feed into the catalytic reactor;

a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end;

one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds and configured to cover a portion comprising the first end of each of the plurality of catalyst beds so that feed gas entering the catalytic reactor is substantially prevented from entering each catalyst bed at the first end.

The catalytic reactor of claim 1, wherein two catalyst beds are disposed within the one or more walls.

The catalytic reactor of claim 2 wherein the catalytic reactor has one nonporous cover configured to cover a portion of each of the two catalyst beds.

The catalytic reactor of any of claims 2 and 3, wherein the gas feed does not enter the two catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet, instead, the gas feed enters each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet.

The catalytic reactor of any of claims 1 to 3, wherein the catalytic reactor comprises a cylindrical vessel.

The catalytic reactor of claim 2 to 3, further comprising:

a central chamber between the two catalyst beds adapted to receive gas flowing from the catalyst beds.

The catalytic reactor of claim 6, further comprising:

a manifold below the catalyst beds and in fluid communication with the central chamber.

8. The catalytic reactor of claim 7, further comprising:

one or more outlets in fluid communication with the manifold configured to flow one or more gases from the manifold.

9. The catalytic reactor of claim 8, wherein the one or more gases comprise air when a decarburizing cycle is in operation.

10. The catalytic reactor of claim 8, wherein the one or more gases comprise hydrocarbon gas when a dehydrogenation cycle is in operation.

11. The catalytic reactor of any of claims 1 to 3, wherein the one or more nonporous covers comprises a refractory arch roof shroud.

12. The catalytic reactor of any of claims 1 to 3, wherein the one or more nonporous covers comprises an SAE 310S stainless steel curved metal plate.

13. The catalytic reactor of any of claims 1 to 3, wherein the one or more nonporous covers comprises an SAE 304L stainless steel curved plate with a polymeric coating/painting.

14. The catalytic reactor of any of claims 1 to 3, wherein the one or more nonporous covers channel the flow of gas feed along side walls prior to the gas feed entering the catalyst beds.

15. A method of dehydrogenating hydrocarbon, the method comprising:

flowing a gas feed into a catalytic reactor through a feed inlet adapted to channel flow of a gas feed into the catalytic reactor, the catalytic reactor having one or more walls and a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet, a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end;

channeling the gas feed entering the catalytic reactor so that it is substantially prevented from entering each catalyst bed at the first end, the channeling performed by one or more nonporous covers disposed between the feed inlet and the plurality of catalyst beds. The method of claim 15, further comprising:

flowing the gas feed so that the gas feed does not enter the plurality of catalyst beds in a direction parallel to direction of flow of the gas feed through the feed inlet, instead, the gas feed enters each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet.

The method of claim 16, further comprising:

flowing gas product from the catalyst beds to a central chamber between the plurality of catalyst beds, the central chamber adapted to receive the gas product flowing from the catalyst beds.

The method of claim 17, further comprising:

flowing the gas product through a manifold below the catalyst bed and in fluid communication with the central chamber.

A method of retrofitting a catalytic reactor, the method comprising:

providing a catalytic reactor that comprises:

one or more walls;

a feed inlet adapted to channel flow of a gas feed into the catalytic reactor;

a plurality of catalyst beds disposed within the one or more walls, each catalyst bed comprising a first end disposed near the feed inlet; a second end disposed further from the feed inlet than the first end, and a middle portion disposed between the first end and the second end;

adding one or more nonporous covers between the feed inlet and the plurality of catalyst beds so that the one or more nonporous covers cover a portion comprising the first end of each of the plurality of catalyst beds and that feed gas entering the catalytic reactor is substantially prevented from entering each catalyst bed at the first end.

The method of claim 19, wherein the one or more nonporous covers and the one or more walls are adapted to flow the gas feed to enter each catalyst bed in a direction lateral and/or slanted to the direction of flow of the gas feed through the feed inlet.