Patent Application
20240207801
The present disclosure relates to catalyst regenerators having reduced carbon emissions.
Regenerated and heated catalyst is used in numerous chemical processing systems. Conventional techniques for regenerating catalyst, or ‘reactivating’ catalyst, use fossil fuels to create the heat necessary to reactivate catalysts.
The present disclosure addresses the need for regenerators that reduce use of fossil fuels to reactivate catalysts, as well as other needs of the prior art.
In aspects, the present disclosure provides a system for regenerating a spent catalyst into a reactivated catalyst having a predetermined heat content. The system may include a reactor configured to generate the spent catalyst; a regenerator configured to regenerate the spent catalyst from the reactor; and an electrically energized heater configured to selectively increase a heat content of the spent catalyst to the predetermined heat content, the heater having a plurality of energy emitting members at least partially immersed in the spent catalyst.
In aspects, the present disclosure provides a method for regenerating a spent catalyst into a reactivated catalyst having a predetermined heat content. The method may include the steps of generating a spent catalyst in a reactor; receiving the spent catalyst in a regenerator; at least partially immersing a plurality of energy emitting member of a heater in the spent catalyst; and selectively operating the heater to increase a heat content of the spent catalyst to the predetermined heat content.
It should be understood that certain features of the disclosure have been summarized rather broadly in order that the detailed description thereof that follows may be better understood, and in order that the contributions to the art may be appreciated. There are, of course, additional features of the disclosure that will be described hereinafter and which will in some cases form the subject of the claims appended thereto.
For detailed understanding of the present disclosure, references should be made to the following detailed description taken in conjunction with the accompanying drawings, in which like elements have been given like numerals and wherein:
In aspects, the present disclosure provides systems and related methods for reactivating a catalyst that is circulated in a processing system. In certain embodiments, the present disclosure provides regenerators having reduced carbon emissions as compared to regenerators that use only fossil fuels to generate heat. There are shown in the drawings, and herein will be described in detail, specific embodiments of the present disclosure with the understanding that the present disclosure is to be considered an exemplification of the principles of the disclosure and is not intended to limit the disclosure to that illustrated and described herein.
Referring initially to
The regenerator 100 includes a vessel 110 that houses a separation system 112 in an interior 114. The separation system 112 may be a cyclonic separation device configured to separate gases from solids. Gases inside the interior 114 may exit via a flue gas plenum 116. In some embodiments, the outlet 108 may be in fluid communication with a catalyst stripper 118, which circulates the reactivated catalyst to the reactor (not shown). Air may be blown into the interior 114 via an inlet 119 to maintain catalyst fluidization and circulation and potentially to burn coke, if present, off of the catalyst particles. As used throughout, the term “spent catalyst” refers to catalyst at any stage of the reactivation process. In some embodiments, the reactivation process is not complete until the catalyst enters a reactor. In other embodiments, the reactivation process is complete after the catalyst exits via the outlet 108.
In accordance with the present teachings, the regenerator 100 can use, if needed, electrical energy to selectively increase the heat content to a catalyst body formed by the spent catalyst. The regenerator 100 may operate in several operating modes. In one mode, the regenerator 100 uses only electrical energy to increase the heat content of the catalyst body to the predetermined heat content. In another mode, the regenerator 100 increases the heat content to the predetermined heat content by using electrical energy in combination with one or more non-electrical energy sources such as the combustion of coke deposits on the catalyst and/or a supplemental fuel source. In still another mode, the regenerator 100 may use only one or more non-electrical energy sources. For example, in some situations, the combustion of coke deposits may supply all of the heat content required to obtain the predetermined heat content. Thus, “selectively increase” means that the regenerator may have several operating modes that can be selected as needed to obtain the predetermined heat content. In one non-limiting embodiment, personnel can monitor operating parameters such as temperature, flow rates, and/or pressure and manually actuate a switch or other device to select the addition of heat content by the regenerator 100. In another non-limiting embodiment, a suitably programmed processor may receive signals from sensors, e.g., temperature gauges, and autonomously select or de-select the adding of heat by the regenerator 100.
In some embodiments, the electrical energy may be generated using a renewable energy source (e.g., wind, solar, hydroelectric, tidal, geothermal, etc.). In other embodiments, the electrical energy may be generate using a low carbon/no carbon energy source (e.g., hydrogen, nuclear, etc.). In still other embodiments, the electrical energy may be generated using hydrocarbon-based fuels.
In one arrangement, one or more electrically energized heaters 130 may be positioned external to the vessel 110. The heater 130 may utilize a ‘shell-and-tube’ type of configuration. As shown, the heater 130 may include a shell 132 in which are disposed an array of energy emitting members 134. The energy emitting members 134 may be energized using a suitable control system 136 and power source 137. The power source 137 may be a renewable power source or conventional power source as previously described. Catalyst from the vessel 110 enters the shell 132 via a suitable inlet 138 and flows downward along the energy emitting members 134. At or near the bottom of the shell 132, a fluidizing agent, such as steam or air, is injected into the shell 132 via a header or other inlet 140. The fluidizing agent flows upward to a gas outlet 142 as the catalyst flows downward to the outlet 144. In embodiments, catalyst density may range between 35 to 40 lb/ft3 and vapor superficial velocity may range between 0.2-0.4 ft/s. In other embodiments, catalyst density may range between 25 to 50 lb/ft3 and vapor superficial velocity may range between 0.1-0.8 ft/s. In still other embodiments, catalyst density may range between 15 to 60 lb/ft3 and vapor superficial velocity may range between 0.01-1.5 ft/s. While one shell 132 is shown, it should be understood that multiple shells may also be used.
In some embodiments, the energy emitting members 134 may be electrical heating members or include electrical heating members. That is, the energy emitting members 124 may directly or indirectly heat the catalyst. It should be noted that during operation, the energy emitting members 134 are immersed in a body of catalyst. By immersed, it is meant at least partially surrounded by catalyst. Thus, the energy emitting members 134 can emit energy, here thermal energy, in multiple directions and multiple locations within the catalyst body. In other embodiments, the energy emitting members 134 may utilize other energy transmission media, such as infrared or induction.
Referring to
The regenerator 100 may be configured to use electrical energy to reactivate the spent catalyst. In this embodiment, an electrically energized heater 130 may be positioned internal to the vessel 110. The heater 130 may use an array of energy emitting members 134 as described previously. The energy emitting members 134 may be energized using a suitable control system 136/power source 137, as described previously. At or near the bottom of the vessel 110, a fluidizing agent, such as steam or air, is injected via a header or other inlet 140. As in the
Referring to
In still other variants not shown, the regenerator may utilize a back-mix flow electrically energized external heater arrangement. In such arrangements, the regenerator does not have a separate inlet and exit for the catalyst. Instead, the catalyst exits from the same passage from which the catalyst entered the regenerator.
Referring to
Thus, it should be noted that the energy emitting members 134 are not limited to any particular geometric configuration, shape or arrangement. Moreover, arrays of energy emitting members 134 may be distributed throughout the regenerator 100 (
The words “comprising” and “comprises” as used throughout the claims, are to be interpreted to mean “including but not limited to” and “includes but not limited to”, respectively.
To the extent used herein, the word “substantially” shall mean “being largely but not wholly that which is specified.”
As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
To the extent used herein, the term “about” in reference to a given parameter is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the given parameter).
To the extent used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
The foregoing description is directed to particular embodiments of the present disclosure for the purpose of illustration and explanation. It will be apparent, however, to one skilled in the art that many modifications and changes to the embodiment set forth above are possible without departing from the scope of the disclosure. It is intended that the following claims be interpreted to embrace all such modifications and changes.
