Use of treating elements to facilitate flow in vessels

Abstract

A method for facilitating the distribution of the flow of one or more streams within a bed vessel is provided. Disposed within the bed vessel are internal materials and structures including multiple operating zones. One type of operating zone can be a processing zone composed of one or more beds of solid processing material. Another type of operating zone can be a treating zone. Treating zones can facilitate the distribution of the one or more streams fed to processing zones. The distribution can facilitate contact between the feed streams and the processing materials contained in the processing zones.

Description

RELATED APPLICATIONS[0001]This application claims the benefit, and priority benefit, of U.S. Provisional Patent Application Ser. No. 62 / 314,069, filed Mar. 28, 2016 and U.S. Provisional Patent Application Ser. No. 62 / 294,768, filed Feb. 12, 2016, the contents of each of which are incorporated by reference herein in their entirety.BACKGROUND[0002]Field of the Invention[0003]The presently disclosed subject matter relates to facilitating the flow of streams within vessels utilized in the process industry.[0004]Description of Related Art[0005]The number of bed vessels installed and operating in industry totals in the tens of thousands worldwide. Bed vessels are usually large with diameters ranging from 4 to 18 feet and heights from 10 to over 100 feet. The volume of such bed vessels is substantially filled with bed vessel internals. Each year, the number of bed vessels that are shutdown or are constructed and commissioned totals in the hundreds. The designed lifetime of these bed vessel...

AI Technical Summary

Benefits of technology

[0015]In certain illustrative embodiments, a method of improving the distribution and redistribution of the flow of one or more streams in a bed vessel is provided. The bed vessel can be configured to have more than one processing zone positioned vertically with respect to one another within the bed vessel with one uppermost processing zone and one or more processing zones positioned downstream of the uppermost processing zone. The processing zones can contain beds of solid processing material elements. Redistribution treating zones can be disposed downstream of an upstream processing zone and upstream of a downstream processing zone in order to facilitate effective and efficient redistribution of the flow of streams exiting the upstream processing zone and entering said downstream processing zone. One primary objective of such redistribution treating zones is to facilitate the dispersal across the cross sectional area of the downstream processing zone of the stream exiting the upstream processing zone and entering the downstream processing zone. The stream exiting the redistribution treating zone and entering the downstream processing zone can be subdivided into small individual stream rivulets, which is an improvement over the channeled stream entering the redistribution treating zone from the upstream processing zone. The dispersed stream rivulets affect improved contact with and utilization of the beds of solid processing material elements contained in the downstream processing zone. The bed vessel's utilization and performance can be significantly improved compared with the utilization and performance of a bed vessel configuration that excludes the presence of said redistribution treating zones.

[0016]In certain illustrative embodiments, a method of improving flow distribution for one or more streams in, or at various locations throughout, a bed vessel is provided. The one or more streams can be passed through an upstream processing zone and a downstream processing zone within the bed vessel. The upstream processing zone and downstream processing zone can each contain one or more beds of solid processing material elements. The one or more streams can also be passed through at least one redistribution treating zone located between the upstream processing zone and downstream processing zone. The redistribution treating zone can contain treating material that redistributes the flow of the one or more streams. The beds of solid processing material elements in the upstream processing zone can be separated from the treating materials in the immediate downstream redistribution zone by a permeable barrier. Alternatively, the upstream processing zone materials can be directly adjacent to and in contact with the treating materials in the immediately downstream redistribution treating zone, without any physical equipment or barrier therebetween, such that the solid processing material elements from the upstream processing zone are capable of at least partially commingling with the treating materials in the immediately downstream redistribution treating zone to create a combo-zone containing both solid processing material elements and treating materials and possessing both processing and stream distribution treatment functionalities. Such migration is typically limited to the first few inches of depth of the redistribution treating zone materials. The solid processing material elements can occupy at least 20% of the volume of that portion of the layer of treating materials contained in the redistribution treating zone into which the solid processing material elements have migrated.

[0017]The redistribution treating zone can be downstream of and directly adjacent to the upstream processing zone such that certain of the solid processing material elements from the upstream processing zone migrate into the redistribution treating zone to create a combo-zone having both solid processing material elements and treating materials commingled therein. In certain illustrative embodiments, there is no physical equipment or barrier disposed in the vessel between the upstream processing zone and the immediately downstream treating zone. The solid processing material elements in the upstream processing zone can migrate into the layer of treating materials contained in the immediately downstream redistribution treating zone. Such migration is typically limited to the first few inches of the redistribution treating zone materials. The solid processing material elements can occupy at least 20% of the volume of that portion of the layer of treating materials contained in the redistribution treating zone into which the solid processing material elements have migrated. In certain illustrative embodiments, solid processing material elements are initially mixed with the materials in the treating zone, such that co-mingling is achieved without the need for migration from other zones.

[0020]In certain illustrative embodiments, a method of improving the flow distribution of one or more streams in and throughout a bed vessel is provided in which redistribution treating zones containing a plurality of treating elements is disposed immediately downstream of processing zones. In such a configuration, the solid processing material elements in an upstream processing zone can migrate into the redistribution treating zone and commingle with the treating elements in the redistribution treating zone to form a combo-zone with both solid processing material elements and treating elements and their functionalities.

[0021]In certain illustrative embodiments, a method of improving the flow distribution of one or more streams in and throughout a bed vessel is provided in which redistribution treating zones containing a plurality of treating elements is disposed immediately downstream of processing zones. In such a configuration, the solid processing material elements in an upstream processing zone are commingled with the treating elements in the redistribution treating zone to form a combo-zone with both solid processing material elements and treating elements and their functionalities.

Problems solved by technology

Many bed vessels face challenges associated with sustaining effective and efficient utilization of bed vessel internals including effective and efficient stream flow distribution across and throughout the beds of solid processing material elements installed in the bed vessels.

Inadequate stream flow distribution leads to coalescence of small stream rivulets into larger streams resulting in stream flow channeling which can result in bypassing portions of the bed vessel processing internals.

Stream flow channeling within a bed vessel can occur and change over time due to shifts in operating conditions (e.g., changing compositions of feed streams), operations upsets (e.g., power surges / cuts, pump failures, etc.), natural or accelerated aging of bed vessel internals and the like.

Channeling is undesirable because it results in areas of underexposed and underutilized bed vessel internal materials and areas of overexposed materials.

The former can result in significant loss of bed vessel productivity and profitability.

The latter can result in so-called “hot spots” where sharp temperature gradients cause damage to the vessel and its internals.

This mode of operation results in reduced “on-oil” operating time with accompanying loss of bed vessel productivity and profitability.

Such devices are costly to design, fabricate, install, operate and maintain and requires specially-trained personnel to do so.

These conventional devices also require complex monitoring and containment systems to ensure segregation from other bed vessel internals.

Any loss of catalyst containment can result in process and safety risks.

The very presence of such conventional redistribution and containment equipment and the difficulty of sustaining their stable and controlled operation can lead to problems up to and including development of bed vessel shell hot spots leading potentially to rupture of the bed vessel itself.\

The very presence of such conventional structured engineered devices consumes space that could otherwise be consumed by more productive and more profitable bed vessel internals, such as catalyst.

Such migration is typically limited to the first few inches of depth of the redistribution treating zone materials.

Such migration is typically limited to the first few inches of the redistribution treating zone materials.

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