Use of a treatment element for promoting flow in a container

Abstract

To provide a method for improving flow distribution to promote flow in a vessel used in the chemical process industry.SOLUTION: A method of improving flow distribution of one or more streams in a process vessel (10) in which at least two process zones (4060,) containing beds of solid process material (4565) are located, the method comprising: A method of improving flow distribution comprising disposing at least one redistribution treating zone 50 between process zones 10, the redistribution treating zone 50 comprising a plurality of treatment elements 55 operable to reduce flow channeling and redistribute flow through the redistribution treating zone 50, wherein process material 45 intermingles with the treatment elements 55 in the redistribution treating zone 50 to form a combined zone comprising both process material 45 and treatment elements 55.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] The subject matter of the present invention relates to a process for facilitating flow in vessels used in the chemical process industry. [Background technology]

[0002] This application claims the benefit of and priority to U.S. Provisional Patent Application Nos. 62 / 314,069, filed March 28, 2016, 62 / 294,768, filed February 12, 2016, and U.S. Patent Application No. 15 / 265,405, filed September 14, 2016, the contents of each of which are incorporated herein by reference in their entirety.

[0003] The total number of installed and operating bed vessels in industry is in the tens of thousands worldwide. Bed vessels are typically large, ranging from 4 to 18 feet (1.2 to 5.5 m) in diameter and from 10 to over 100 feet (3.05 to over 30.48 m) in height. The volume of such bed vessels is substantially filled by the bed vessel internals. Hundreds of bed vessels are decommissioned or constructed and commissioned each year. The design life of these bed vessels is typically measured in decades. Bed vessels used in industry contain suitable contents, which may include one or more layers (beds) of solid processing material elements that facilitate the intended chemical process operation. Such solid processing material elements may include, for example, reaction-promoting catalysts and mass transfer enhancers, including sieves and sorbents. Floor bins and their contents represent a significant investment by the floor bin owner.

[0004] The normal length of a typical bed vessel's "on oil" operating cycle (from vessel start-up to vessel shutdown) is measured in months or years. Steady operation is usually terminated when the bed vessel's contents reach their performance limits or when the bed vessel's operating conditions, such as temperature or pressure, exceed their operational limits. Such a shutdown is typically followed by regeneration, repair, and / or replacement of the bed vessel's contents, followed by resumption of operation.

[0005] It is known in the art to use suitable materials to promote flow distribution of the stream entering the bed vessel. The purpose of such distribution is to sub-divide the stream into streams that improve contact of the stream with the process material in the bed vessel. Three-dimensional reticulation is known to promote flow distribution. For example, U.S. Patent Nos. 5,629,995, 5,629,995, 5,629,995, 5,629,995, and 5,629,995, respectively, describe such reticulated materials.

[0006] Many bed vessels face challenges associated with maintaining effective and efficient utilization of the bed vessel contents, including effective and efficient flow rate distribution on and throughout the bed of solid process material elements installed within the bed vessel. Improper flow rate distribution can result in the confluence of small stream trickles into larger streams, resulting in flow channeling that can result in the bypass of a portion of the bed vessel's process contents.

[0007] Flow path formation within the bed vessel may occur and change over time due to fluctuations in operating conditions (e.g., changing composition of the feed stream), operational disruptions (e.g., power surges / shutdowns, pump failures, etc.), natural or accelerated aging of the bed vessel contents, etc. Channeling can occur when merging is promoted by smaller fluid streams in contact with each other or by contact with the contents of other bed vessels or the bed vessel itself. Channeling is undesirable because it results in areas of underexposed and underutilized bed vessel content material and areas of overexposed material. The former can result in significant losses in bed vessel productivity and profitability. The latter can result in so-called "hot spots" where steep temperature gradients can cause damage to the vessel and its contents.

[0008] One approach to dealing with these situations has been to tolerate moderate bed vessel performance degradation and operate the vessel until performance deteriorates to an unacceptable level. At such time, the contents of the bed vessel are shut down so that they can be adjusted, rejuvenated, or replaced. This mode of operation results in a reduction in "on-oil" operating time, with a concomitant loss in bed vessel productivity and profitability.

[0009] Another approach has been to install one or more conventional structured engineering devices at appropriate locations within the bed vessel to facilitate redistribution of flow within and across its cross-section, thereby increasing contact of the flow with the bed vessel's contents (including the bed of solid process material) and reducing the adverse consequences of flow channelization. Such conventional devices typically include structures of engineering equipment that fit snugly along the inside of the bed vessel and may occupy up to 10 feet (3.05 m) deep within the bed vessel. Such devices are costly to design, fabricate, install, operate, and maintain, and require specially trained personnel to implement them. These conventional devices also require complex monitoring and containment systems to ensure isolation from the contents of other bed vessels. In the catalytic reactor example, this involves isolating the conventional redistribution devices from the catalyst with "catalyst containment" devices and means. Any loss of catalyst containment can pose chemical process and safety risks. Significant measures are taken to ensure catalyst containment, and bed vessel space is consumed. The very existence of such conventional redistribution and containment devices and the difficulty of maintaining their stable, controlled operation can lead to challenges up to and including the development of hot spots in the bed vessel shell that can potentially lead to the destruction of the bed vessel itself.

[0010] The very presence of such conventional structured engineering devices consumes space that could otherwise be directed to more productive, more profitable bed vessel contents, such as catalyst. An example of such a structured engineering device and its use as a flow distributor is shown in U.S. Patent No. 5,623,999, issued January 1, 2008 to UOP, LLC of Des Plaines, Illinois.

[0011] Improvements in this area of ​​technology are desirable. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] U.S. Patent No. 6,258,900 [Patent Document 2] U.S. Patent No. 6,291,603 [Patent Document 3] U.S. Patent No. 7,265,189 [Patent Document 4] U.S. Patent No. 7,314,551 Summary of the Invention

[0013] Various specific embodiments of methods for facilitating flow distribution and redistribution of one or more streams within a vessel are provided in accordance with the subject matter of the present invention. The streams may include liquid and vapor streams, combinations of the two, and mixtures of the two. The vessel may be used for a chemical process. This may include those containing a bed of solid material used for the purpose of

[0014] In certain specific embodiments, a method for improving the distribution and redistribution of flow rates of one or more streams within a bed vessel is provided. The bed vessel may be designed to have two or more chemical process zones arranged perpendicular to one another within the bed vessel, with one uppermost chemical process zone and one or more chemical process zones arranged downstream of the uppermost chemical process zone. The process zones may comprise beds of solid process material elements. To promote effective and efficient redistribution of flow rates of streams exiting an upstream process zone and entering said downstream process zone, a redistribution process zone may be located downstream of the upstream process zone and upstream of the downstream process zone. One primary purpose of such a redistribution process zone is to promote dispersion of the stream exiting the upstream process zone and entering the downstream process zone across the cross-sectional area of ​​the downstream process zone. The stream exiting the redistribution process zone and entering the downstream process zone may be sub-divided into small individual streams, which is an improvement over a channel-formed stream entering the redistribution process zone from the upstream process zone. The dispersed flow rivulets provide improved bed contact and operability of the solid process material elements contained in the downstream process zones, and the operability and performance of the bed vessel may be significantly improved compared to the operability and performance of bed vessel configurations that exclude the presence of the redistribution treatment zone.

[0015] In certain specific embodiments, a method for improving flow distribution for one or more streams at various locations within or throughout a bed vessel is provided. The one or more streams may pass through an upstream process zone and a downstream process zone within the bed vessel. The upstream process zone and the downstream process zone may each contain one or more beds of solid process material elements. The one or more streams may also pass through at least one redistribution treatment zone located between the upstream process zone and the downstream process zone. The redistribution treatment zone may contain a treatment material that redistributes the flow rates of the one or more streams. The bed of solid process material elements in the upstream process zone may be separated from the treatment material in the adjacent downstream redistribution zone by a permeable barrier. Alternatively, the aid from the upstream process zone may be directly adjacent to and in contact with the process material in the adjacent downstream redistribution processing zone, without any physical device or barrier therebetween, such that the solid process material elements from the upstream process zone may at least partially intermingle with the process material in the adjacent downstream redistribution processing zone to form a combined zone containing both the solid process material elements and the process material and having both chemical process functionality and flow distribution processing functionality. Such migration is typically limited to the first few inches of depth of the material in the redistribution processing zone. The solid process material elements may occupy at least 20% of the volume of that portion of the layer of process material contained in the redistribution processing zone into which the solid process material elements migrated.

[0016] The redistribution processing zone may be downstream of and directly adjacent to the upstream processing zone, such that certain solid process material elements from the upstream processing zone migrate into the redistribution processing zone to form a combo-zone having both the solid process material elements and the processing material intermixed therein. In certain specific embodiments, no physical device or barrier is disposed within the vessel between the upstream processing zone and the adjacent downstream processing zone. The solid process material elements in the upstream processing zone may migrate into the layer of processing material contained in the adjacent downstream redistribution processing zone. Such migration is typically limited to the first few inches of material in the redistribution processing zone. The solid process material elements may occupy at least 20% of the volume of the portion of the layer of processing material contained in the redistribution processing zone into which the solid process material elements migrate. In certain specific embodiments, the solid process material elements are first mixed with the material in the processing zone so that co-mixing is achieved without the need for migration from other zones.

[0017] The redistribution treatment area may have a depth of 1 foot (30.48 cm) or less. The redistribution treatment area may have a depth of 2 feet (61 cm) or less. The redistribution treatment area may have a depth of 4 feet (122 cm) or less.

[0018] The redistribution treatment zone may include a treatment material. Such material may include at least one layer of fixed, form-fitting material that conforms to the interior dimensions of the bed vessel. Such form-fitting material, such as a fibrous mesh, provides a porous structure that promotes flow redistribution. Alternatively, the treatment material may include a plurality of treatment elements. The treatment elements may be individual treatment elements. The treatment elements may be arranged in layers. The treatment elements may be randomly packed treatment elements. One or more treatment elements may be ceramic reticulations. One or more treatment elements may have a quasi-ellipsoid shape. One or more treatment elements may have a triaxial ellipsoid shape. One or more treatment elements may have an oblate spheroid shape. One or more treatment elements may have a prolate spheroid shape. One or more of the treatment elements may have a briquette shape. One or more of the treatment elements may have an asymmetric oblate spheroid shape. One or more of the treatment elements may have an aspherical ellipsoid shape. One or more of the treatment elements may have at least one opening formed therein. One or more of the treatment elements may have at least one opening formed therethrough. One or more of the treatment elements may have one or more asperities formed on their surface. The asperities may include one or more of grooves, vanes, struts, filaments, spikes, or hairs.

[0019] In certain specific embodiments, a method is provided for improving flow distribution of one or more streams in and throughout a bed vessel in which a redistribution processing zone containing a plurality of processing elements is located adjacent downstream of the processing zone. In such a configuration, solid process material elements in the upstream processing zone may migrate into the redistribution processing zone and intermingle with the processing elements in the redistribution processing zone to form a combination zone containing both solid process material elements and processing elements and their functionality.

[0020] In certain specific embodiments, a method is provided for improving flow distribution of one or more streams within and throughout a bed vessel in which a redistribution processing zone containing a plurality of processing elements is disposed adjacent downstream of the processing zone. In such a configuration, solid process material elements in the upstream processing zone intermingle with the processing elements in the redistribution processing zone to form a combination zone containing both the solid process material elements and the processing elements and their functionality. [Brief explanation of the drawings]

[0021] [Figure 1A] FIG. 1A is a partial cross-sectional side view of a bed vessel having multiple zones in accordance with a specific embodiment of the present inventive subject matter. [Figure 1B] FIG. 1B is a partial cross-sectional side view of a bed container having multiple zones, with an enlarged view of adjacent zones within the bed container having permeable barriers between the zones, according to a specific embodiment of the present inventive subject matter. [Figure 2A] FIG. 2A is a partial cross-sectional side view of a bed vessel having multiple zones in accordance with a specific embodiment of the present inventive subject matter. [Figure 2B] FIG. 2B is a partial cross-sectional side view of a bed container having multiple sections, with an enlarged view of a combination area between two adjacent sections within the bed container, according to a specific embodiment of the present inventive subject matter. [Figure 3] FIG. 3 is a graph illustrating the results of a flow redistribution test on an empty test vessel, in accordance with an illustrative embodiment of the present subject matter. [Figure 4]FIG. 4 is a graph illustrating the results of a flow redistribution test for a test element bed of randomly packed 3 / 4" (1.9 cm) support balls, in accordance with an illustrative embodiment of the present inventive subject matter. [Figure 5] FIG. 5 is a graph illustrating the results of a flow redistribution test for a randomly packed bed of processing elements, in accordance with an illustrative embodiment of the present subject matter.

[0022] While the inventive subject matter will be described in connection with a preferred embodiment, it will be understood that it is not intended to limit the inventive subject matter to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the inventive subject matter as defined by the appended claims. DETAILED DESCRIPTION OF THE INVENTION

[0023] Various specific embodiments of methods for promoting flow redistribution and lateral redistribution of one or more streams within a bed vessel in accordance with specific embodiments of the present subject matter are provided.

[0024] The concept of "redistribution" described in the subject matter of this invention relates to the division and dispersion of process streams across and throughout the contents contained within a bed vessel. Such division and dispersion is facilitated by redistribution treatment zones located to counteract undesirable flow confluence effects that induce flow channeling and, at best, prevent the process zones located within the bed vessel from achieving their intended performance, and at worst, induce a dangerous operating environment that increases operational risk.

[0025] In certain specific embodiments, internal materials and structures and multiple operating zones are disposed within such a bed vessel. One type of operating zone may be a process zone comprising one or more beds of solid processing material. A second type of operating zone may be a treatment zone. The treatment zone may facilitate distribution and dispersion of one or more streams flowing out of or into the process zone. The distribution may facilitate contact between the streams and the bed of solid process material elements contained within the process zone. A treatment zone disposed between an upstream process zone and a downstream process zone may also be referred to as a redistribution treatment zone.

[0026] In certain specific embodiments, a redistribution treatment zone may be used within the bed vessel. The redistribution treatment zone may contain treatment material at a depth and location sufficient to promote desired flow redistribution and redistribution across and throughout the bed of the downstream process zone of solid process material elements.

[0027] In certain specific embodiments, the redistributed treatment material may comprise at least one layer of fixed, form-fitting material that conforms to the interior dimensions of the bed vessel. Alternatively, the redistributed treatment material may be in the form of a plurality of individual treatment elements, randomly or otherwise packed into a layer of the treatment zone.

[0028] In certain specific embodiments, the individual redistribution treatment elements may have a variety of shapes and sizes, including disks, spheres, rings, wheels, hollow tubes, etc. One or more of the redistribution treatment elements may have at least one or more openings therein and / or therethrough. One or more of the redistribution treatment elements may have one or more asperities formed on their surface, which may include, but are not limited to, flutes, fins, struts, filaments, spikes, or hairs. The one or more redistribution treatment elements may be ceramic reticulates. The reticulates are characterized by having one or more open cells that form multiple, interconnected fluid flow pathways within and through the element. Such pathways may have a tortuous geometry. Such redistribution treatment elements, including their openings, ridges, and interconnected internal fluid flow pathways, have a large surface area that facilitates flow division and redistribution. Such redistribution treatment elements are hereinafter referred to as "treatment elements."

[0029] In certain specific embodiments, one or more processing elements have a quasi-ellipsoidal shape. For example, one or more of the pseudo-ellipsoidal treatment elements may have a triaxial ellipsoidal shape. One or more of the pseudo-ellipsoidal treatment elements may also have an oblate spheroid shape. One or more of the pseudo-ellipsoidal treatment elements may also have a prolate spheroid shape. One or more of the pseudo-ellipsoidal treatment elements may also have a briquette shape. One or more of the pseudo-ellipsoidal treatment elements may also have an asymmetric ellipsoidal shape. One or more of the pseudo-ellipsoidal treatment elements may also have a non-spherical ellipsoidal shape.

[0030] In certain specific embodiments, the pseudo-ellipsoid shapes of the prolate, oblate, and asymmetric morphologies may have one mathematical model that can be generalized to all three morphologies. For example, the oblate and prolate morphologies of the oblate spheroid may be represented by the following formula:

[0031]

number

[0032] In particular cases, the shape may be a generic asymmetric ellipsoid (a=b, b=c or a=c) according to the formula:

[0033] In certain specific embodiments, a briquette shape may be defined as the volumetric intersection of two or more oval cylinders, or shapes substantially similar to such shapes, with the major axes of the oval faces of each cylinder coplanar.

[0034] In certain specific embodiments, the redistribution treatment zone within the bed vessel may have a depth of 1 foot (30.5 cm) or less. Alternatively, the redistribution treatment zone may have a depth of 2 feet (61 cm) or less. Alternatively, the redistribution treatment zone may have a depth of 4 feet (122 cm) or less.

[0035] In certain specific embodiments, a redistribution processing zone containing a plurality of randomly packed individual processing elements may be positioned downstream adjacent to an upper processing zone without any barrier between the two zones. In such a configuration, individual solid process material elements in the upper processing zone may migrate into the top few inches of the layer of processing elements in the downstream redistribution processing zone and intermingle with these elements. In certain specific embodiments, typical processing elements each have a size up to 50 times that of an individual solid process material element. In certain specific embodiments, in some solid process material elements, the processing element may have a size more than 100 times that of an individual solid process material element. In certain specific embodiments, in some solid process material elements, the processing element may have a size more than 100 times that of an individual solid process material element. In some cases, the processing elements may be over 200 times the size of the individual solid process material elements.

[0036] In certain specific embodiments, commingling of individual, solid process material elements from an upper process zone with processing elements in a downstream redistribution processing zone results in the solid process material elements occupying at least 20% of the volume of that portion of the redistribution processing zone into which said solid process material elements migrated. Such zones containing commingled solid process material elements and processing elements are referred to herein as "combo-zones," where the solid process material elements mix and / or migrate into the redistribution processing zone and commingle with the processing elements present in the processing zone. Combination zones are particularly beneficial because they occupy a moderate bed depth and simultaneously, and inexpensively, improve both the chemical process function and the redistribution function performed in the bed vessel.

[0037] To facilitate mixing of the materials in the combination zone, the method of filling the bed vessel with materials may require successive fillings, such as partial filling of a portion of the process material contained in the redistribution zone, then partial filling of a solid process material element, then a processing element, and then further partial filling of the next process material element. In certain specific embodiments, filling in this manner is believed to facilitate the transfer of material from one zone to another within the vessel and the mixing of said material within the combination zone during chemical process operation. In certain specific embodiments, the material may also be mixed during the filling period, such that mixing of the materials within the combination zone is initially achieved without the need for any material to transfer from one zone to another within the vessel.

[0038] The redistribution treatment zone may have a depth and area sufficient to effectively facilitate flow redistribution and redistribution of the fluid stream exiting the redistribution treatment zone and entering the downstream process zone, thereby improving the utilization and performance of the adjacent downstream process zone.

[0039] The redistribution processing section can eliminate the need for expensive and hazardous conventional structured engineering equipment, freeing up valuable vessel volume (i.e., bed depth) for more productive uses such as additional process materials (e.g., catalysts).

[0040] In certain specific embodiments, the contents of a bed vessel may be designed to include multiple process zones, treatment zones, and / or combination zones. Overall bed vessel performance depends on the proper performance of each zone. Zones with chemical process functionality can perform their intended functions depending on the extent to which the flow passing through them effectively interacts with the solid process material elements within the process zone. Zones with treatment functionality may ensure that an appropriately distributed flow is delivered to the zones with chemical process functionality. Maximizing the performance of a bed vessel, within the dimensional constraints of the bed vessel itself, may typically be achieved by minimizing the space occupied by the process material (i.e., bed depth) and maximizing the space occupied by the process material elements (i.e., bed depth). For example, in certain specific embodiments, the subject matter of the present invention relates to a process zone for solid process material elements consisting of relatively small individual elements whose size ranges from the size of a grain of rice to a kernel of corn.

[0041] Compared to conventional countermeasures, the subject matter of the present invention (i) is cheaper and less complex to plan, process, install, operate, and maintain; (ii) has free volume (i.e., bed depth) within the bed vessel that may be better filled with more productive bed vessel contents, such as additional solid process material elements; and (iii) reduces the "containment facility" associated costs. Advantageously, it provides a flow redistribution option to: (i) avoid operational risks; and (ii) improve the performance and profitability of the bed vessel due to increased contact and interaction between the flow and the process materials of the bed vessel.

[0042] Provided herein are various specific embodiments of methods for redistributing the flow rates of one or more streams within a bed vessel. Referring now to Figure 1A, a bed vessel 10 is shown having two process zones 40, 60 disposed therein. The bed vessel 10 is shown in a downward flow configuration, such that one or more input streams 100 will enter the bed vessel 10 at an inlet 20 and one or more product streams 600 will exit the bed vessel 10 at an outlet 70.

[0043] In certain specific embodiments, influent stream 100 enters the vessel and passes through "upper bed" section 30, which includes element 35. The upper bed section may facilitate distribution of influent stream 100 across the cross-section of process section 40. The upper bed section may also facilitate filtration of particulate contaminants contained within influent stream 100. The upper bed section may also mitigate undesirable compounds contained within influent stream 100. Stream 200 exiting "upper bed" section 30 is believed to have these desirable properties prior to entering process section 40.

[0044] In certain specific embodiments, process stream 200 is chemically processed in process zone 40, and the resulting process stream 300 exits zone 40. A redistribution processing zone 50 containing processing elements 55 may be provided within bed vessel 10 downstream of first process zone 40. In certain specific embodiments, the flow rate of one or more streams 300 may be split and redistributed within redistribution processing zone 50 before being introduced into downstream process zone 60.

[0045] 1B shows an expanded view of redistribution zone 50, including processing element 55, disposed between process zones 40 and 60. In this embodiment, a permeable barrier 80 is disposed between process zone 40 and redistribution zone 50 to separate process zone 40 from redistribution processing zone 50 and to prevent migration of material 45 in the process zone, while still allowing flow 300 to pass from zone 40 to 50. In other words, redistribution processing zone 50 is directly adjacent to upstream process zone 40, and permeable barrier 80 is disposed between zones 50 and 40 such that process material 45 from zone 40 cannot migrate into zone 50, but the flow can pass through barrier 80. In certain specific embodiments, permeable barrier 80 can be a wire screen mesh.

[0046] Figures 2A and 2B show a bed vessel configuration similar to that in Figures 1A and 1B. However, as shown in the enlarged view of Figure 2B, no barrier is disposed between the upper process zone 40 and the redistribution treatment zone 50. In such an embodiment, individual elements of material (auxiliary agent) 45 in the process zone may migrate into the layer several inches above the treatment elements 55 in the redistribution zone to form a combination zone where they may intermingle with it (as shown in Figure 2B).

[0047] Such a combination section configuration, without the constraint of a barrier between the process section and the redistribution treatment section, has the following advantages: (i) eliminates the need for the design, chemical process, installation, operation, and maintenance costs of such a barrier, (ii) saves the space required to install such a barrier, (iii) minimizes the space required to achieve the desired flow redistribution, (iv) allows for increased process section performance by adding process section material in the space increased by the absence of a barrier, (v) increases the performance of the additional process section due to the presence of the process section material within the combination section, and (vi) improves the performance and efficiency of the bed vessel by increasing the interaction between the flow and the process section material of the vessel. Increase productivity and profitability: In certain specific embodiments, the combination zone will comprise the first few inches of depth of the redistribution processing zone 50. This is in the context of bed vessels that may have heights of 100 feet (30.48 m) or more, including the operating zone that substantially fills the vessel. In certain specific embodiments, the combination zone will comprise approximately the first 2 inches (5.08 cm) of depth of the redistribution processing zone 50. In certain specific embodiments, the combination zone will comprise approximately the first 6 inches (15.24 cm) of depth of the redistribution processing zone 50. In certain specific embodiments, the combination zone will comprise approximately the first 12 inches (30.48 cm) of depth of the redistribution processing zone 50.

[0048] In certain specific embodiments, as shown in Figure 1A, redistribution processing zone 50 may be located in or proximate to the upper region of vessel 10 to facilitate redistribution of process stream from process zone 40 into process zone 60 and / or into other, lower located zones within vessel 10. In this regard, there may be one or more process zones and redistribution zones located between streams 500 and 600 within vessel 10 located downstream from zones such as those shown in Figure 1A.

[0049] In certain specific embodiments, flow redistribution is primarily facilitated by contacting the flow with the surfaces of the treatment elements in the redistribution zone. These surfaces include the exterior surface of the treatment element and the interior surface of the treatment element. The internal geometry of the treatment element creates a large surface area formed by openings, ridges, and multiple interconnected internal fluid flow channels.

[0050] In certain specific embodiments, the surface area of ​​each processing element may be 70% to 90% internal surface area, with the remainder being external surface area. As a result, for a given volume of processing elements, a more densely packed processing element shape provides a larger surface area than a loosely packed processing element shape. Therefore, the flow redistribution capacity per volume of packed processing elements increases as the packing density increases. This also applies to the external empty space between packed processing elements, which decreases as the packing density increases.

[0051] In certain specific embodiments, the amount of material required in the processing zone to achieve a desired level of flow redistribution within the bed vessel is primarily a function of the total volume of material, not including external voids relative to the processing elements. Compared to cylindrical networks, pseudo-ellipsoidal processing elements tend to be packed with less void space between individual elements. For example, the processing zone of a pseudo-ellipsoidal processing element may have an external void space of 25 to 35%, compared to 40 to 55% for the processing zone of a cylindrical network. To achieve a desired level of flow redistribution, this may result in the processing zone of the pseudo-ellipsoidal processing element being shallower in depth than that formed by the same amount of cylindrical network. This saves space within the bed vessel.

[0052] Furthermore, the ability of the processing area of ​​an individual processing element to redistribute the flow of one or more process streams depends, in part, on the number of contact points at which each processing element makes contact with its neighboring elements. Maximizing the contact points facilitates flow redistribution through the processing area. The processing area of ​​a pseudo-ellipsoidal processing element may have 60 to 90% more of these contact points than a uniform layer of cylindrical or spherical nets. [Example]

[0053] To facilitate a better understanding of the inventive subject matter, the following examples of particular aspects of particular embodiments are given, which should in no way be construed as limiting or defining the scope of the inventive subject matter.

[0054] Experiments were conducted to demonstrate the redistribution of process streams, including the reduction / elimination / disruption / reduction of flowpath formation of process streams exiting the process zone of an upstream bed vessel and transiting through the redistribution treatment zone of the bed vessel, in accordance with certain specific embodiments of the present subject matter.

[0055] A test structure was assembled that included a vertical cylindrical vessel having a diameter of approximately 12 inches (30.48 cm) and a height of over 36 inches (91.44 cm). A nozzle located above the vessel's center point was used to pass liquid into the vessel. The cylindrical vessel provided sufficient space for a randomly packed bed of test elements to a depth of 36 inches (91.44 cm). Over 300 holes, each 1 / 4" (0.62 cm) in diameter, were drilled in a regular grid pattern through the bottom of the vessel. Each hole was individually connected to plastic tubing that was used to collect and measure the liquid exiting the vessel through the hole. These holes represented a two-dimensional grid area of ​​the vessel's cross-sectional area. The liquid collected through each hole indicated the distribution of the inlet liquid across the vessel's cross-sectional area.

[0056] Liquid was pumped into the vessel through a nozzle. The liquid flow mimicked the channeling flow that occurs in the process section of a commercially available bed vessel. In one test run, the vessel was empty. In other test runs, test elements of various types and depths were placed in the vessel. In each test run, sufficient time elapsed to allow a representative amount of liquid to pass through the tubing-connected holes in the bottom of the vessel. Data collection and analysis produced a graphical plot showing the test element's ability to laterally distribute liquid through the bed of the test element and exit the vessel through the holes in the bottom of the vessel.

[0057] In a typical experiment, a test element is placed in a container, and as the liquid flows around and through the test element, it is dispersed, exits the container through the holes in the grid area, and is collected in the tubes below. The amount of water collected in each tube is measured, and a graph is generated showing the degree to which the element promotes flow redistribution.

[0058] Graphical plots of the flow redistribution test results are shown in Figures 4 through 6. The amount of liquid collected through the tubes connected to the holes in the grid section of the vessel is shown. Figure 4 shows the flow redistribution test results for an empty test vessel. Figure 5 shows the flow redistribution test results for a randomly packed bed of 3 / 4" (1.9 cm) support ball test elements. Figure 6 shows the results for a randomly packed bed of treatment elements in accordance with the present inventive subject matter.

[0059] In Figure 4, there is no test element in the container, and when the liquid flows into the empty cylinder, the bank of the tube is fact lateral distribution of more than 5% of the liquid across the container's grid area. In Figure 5, a randomly packed bed of support balls achieved lateral distribution of more than 55% of the liquid across the container's grid area. In Figure 6, a test run using a randomly packed bed of processing elements in accordance with the present inventive subject matter achieved lateral distribution of more than 92% of the liquid across the container's grid area.

[0060] From these test results, it should be appreciated that a bed of processing elements according to the present inventive subject matter may promote redistribution of a channeled liquid flow exiting an upstream process zone, which may then enter the downstream process zone as a lateral dispersion flow providing improved contact between the flow and the elements of the process zone within the downstream process zone.

[0061] Because obvious modifications and equivalents will be apparent to those skilled in the art, the subject matter of this invention is not limited to the exact details of construction, operation, precise materials or implementations shown and described. It should be understood that the present subject matter should not be limited in any way by the scope of the appended claims.

Claims

1. 1. A method for improving flow distribution of one or more streams in a chemical process vessel, comprising: passing one or more streams through an upstream process zone and a downstream process zone within the process vessel; passing one or more streams through a redistribution treatment zone located between the upstream process zone and the downstream process zone; the upstream process zone and the downstream process zone each comprise one or more beds of process material, and the redistribution treatment zone comprises treatment elements that reduce channel formation of streams exiting the upstream process zone and affect lateral redistribution of flow of one or more streams in the downstream process zone.

2. 2. The method of claim 1, wherein the redistribution treatment zone is immediately adjacent to the upstream process zone such that certain process materials from the upstream process zone can migrate into the redistribution treatment zone to form a combination zone having both the functionality of the process zone and the functionality of the treatment zone.

3. 10. The method of claim 1, wherein the redistribution treatment zone is immediately adjacent to the upstream process zone and a permeable membrane is disposed between the redistribution treatment zone and the upstream process zone, such that process material from the upstream process zone cannot migrate into the redistribution treatment zone but can pass through the membrane.

4. 3. The method of claim 2, wherein no physical devices are disposed within said vessel between said upstream process zone and said downstream redistribution treatment zone.

5. 3. The method of claim 2, wherein the process material migrates to a depth of several inches into a layer of processing elements contained within the redistribution processing zone.

6. 3. The method of claim 2, wherein the process material occupies at least 20% of the volume of the portion of the layer of the processing element contained within the redistribution processing zone into which the process material migrates.

7. 10. The method of claim 1, wherein the redistribution treatment area has a depth of 1 foot (30.5 cm) or less.

8. 10. The method of claim 1, wherein the redistribution treatment area has a depth of 2 feet (61 cm) or less.

9. 10. The method of claim 1, wherein the redistribution treatment area has a depth of 4 feet (122 cm) or less.

10. The method of claim 2 , wherein the redistribution processing area comprises a plurality of processing elements.

11. The method of claim 10 , wherein the processing elements are individual processing elements.

12. 12. The method of claim 11, wherein the individual processing elements are configured to fit the interior dimensions of the bed vessel.

13. The method of claim 10 , wherein the processing elements are randomly packed processing elements.

14. The method of claim 10 , wherein the one or more processing elements are ceramic reticulates.

15. The method of claim 10 , wherein the one or more processing elements have a pseudo-ellipsoidal shape.

16. The method of claim 10 , wherein the one or more processing elements have a three-axis ellipsoidal shape.

17. The method of claim 10 , wherein the one or more processing elements have a flattened oblate spheroid shape.

18. The method of claim 10 , wherein the one or more processing elements have an oblate spheroid shape.

19. The method of claim 10 , wherein the one or more treatment elements have a briquette shape.

20. The method of claim 10 , wherein the one or more processing elements have an asymmetric oblate spheroid shape.

21. The method of claim 10 , wherein the one or more processing elements have a non-spherical ellipsoidal shape.

22. The method of claim 10 , wherein the one or more processing elements have at least one opening formed therein.

23. The method of claim 10 , wherein the one or more processing elements have at least one opening formed therethrough.

24. The method of claim 10 , wherein the one or more processing elements have one or more ridges formed on a surface of the processing element.

25. 25. The method of claim 24, wherein the protuberances comprise one or more of grooves, vanes, struts, filaments, spikes, or hairs.

26. 1. A method for improving flow distribution of one or more streams in a process vessel having disposed therein at least two process zones containing beds of solid process material, comprising: disposing at least one redistribution treatment zone between said process zones; the redistribution treatment zone includes a plurality of treatment elements operable to reduce flow channeling to redistribute the flow rate through the redistribution treatment zone; The method wherein the process material intermixes with the processing element in the redistribution processing zone to form a combination zone containing both the process material and the processing element.

27. 1. A method for improving flow distribution of one or more streams in a process vessel, comprising: disposing at least one redistribution treatment zone between the process zones; The process vessel has disposed therein at least two process zones each containing a bed of solid process material, the redistribution treatment zone including a plurality of operable treatment elements for reducing flow channel formation to redistribute the flow rate through the redistribution treatment zone, and process material in a process zone disposed upstream of the redistribution treatment zone can migrate into the redistribution treatment zone and mix with the treatment elements in the redistribution treatment zone to form a combination zone containing both the process material and the treatment elements.

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