Methods and apparatus for crossflow reactors

Methods and apparatus for cross flow process reactors are disclosed. A disclosed example includes a process chamber having an inlet and an outlet to allow a flow of fluid to flow therethrough and a plurality of trays disposed within the process chamber, and containing bulk material to treat the fluid. The example apparatus also includes a flow director to divide the flow into a plurality of partial flow streams, where each partial flow stream is to be directed towards at least one tray of the plurality of trays.

FIELD OF THE DISCLOSURE

This disclosure relates generally to reactors, and, more particularly, to methods and apparatus for crossflow reactors.

BACKGROUND

Typically, monolithic catalyst reactors, as an example of crossflow reactors, are used to process fluids (e.g., gases) resulting from industrial processes such as combustion processes for steam generation to produce electricity, for example. Often, certain compounds need to be reduced and/or eliminated from the resultant fluid of an industrial process to meet certain environmental and/or regulatory standards.

Monolithic ceramic honeycomb catalyst reactors are typically used, but are relatively expensive and have a decreased resistance towards catalyst poisons and inhibitors. Often, monolithic honeycomb catalysts have high breakage rates due to catalyst damage resulting from significant differences in thermal expansion between the ceramic catalyst and a steel support structure containing and/or positioning the ceramic catalyst. These known monolithic catalyst honeycomb reactors are typically used to avoid lower gas velocities often associated with bulk catalyst (e.g., randomly packed catalysts, etc.). Such lower velocities and/or high pressure drops typically result from crushed and/or damaged catalyst material. The same principle may hold when comparing known monolithic filtration appliances to bulk filtration systems, especially while filtering hot fluids or fluids with fluctuating temperatures, or while comparing regenerative thermal reactors comprising monolithic heat recovery media versus such reactors with bulk heat recovery media.

The figures are not to scale. Instead, to clarify multiple layers and regions, the thickness of the layers may be enlarged in the drawings. Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. As used in this patent, stating that any part (e.g., a layer, film, area, or plate) is in any way positioned on (e.g., positioned on, located on, disposed on, or formed on, etc.) another part, means that the referenced part is either in contact with the other part, or that the referenced part is above the other part with one or more intermediate part(s) located therebetween. Stating that any part is in contact with another part means that there is no intermediate part between the two parts.

DETAILED DESCRIPTION

Methods and apparatus for crossflow reactors are disclosed herein. Typically catalytic reactors such as monolithic honeycomb catalyst reactors are used to treat and/or process gases resulting from industrial processes such as burning fuel to generate electricity, for example. Such reactors typically utilize catalyst blocks having channels and are composed of catalyst material (e.g., precious metals, etc.). The channels typically extend through the entire catalyst block. These monolithic honeycomb catalyst reactors often experience high breakage rates due to catalyst damage induced by differences in thermal expansion between the ceramic-type catalyst block and a steel support structure holding and/or mounting the catalyst block, for example.

Often monolithic honeycomb catalyst reactors are used to avoid decreased velocities associated with bulk material catalyst used in known examples. The decreased velocities are commonly encountered because of crushed or damaged bulk catalyst material, and/or the flow of the process gasses moving through a singular channel (e.g., route), thereby resulting in significant pressure drops as the process fluid flows through an often singular compartment of bulk catalyst material.

The same may hold true while comparing known monolithic filtration appliances to bulk filtration systems, especially while filtering hot fluids or fluids with fluctuating temperatures, or while comparing regenerative thermal reactors comprising monolithic heat recovery media versus such reactors with bulk heat recovery media.

The examples disclosed herein allow use of bulk material, especially bulk material catalyst (e.g., randomly packed catalysts), which has significant cost savings in relation to monolithic types, while maintaining significantly high fluid velocities (e.g., process gas velocities) not typically seen in known bulk material systems. The examples disclosed herein allow effective flow of the process fluid through multiple trays of catalyst disposed within a catalyst reactor vessel. The examples disclosed herein also reduce and/or eliminate crushing and/or damage of the bulk material (e.g., damage due to thermal expansions and/or differences of thermal expansion, etc.), which may cause velocity reduction and/or significant pressure drops (e.g., lower flow rates, etc.) through the bulk material. The examples disclosed herein also allow reactor plants to have a smaller footprint or size. In particular, the examples disclosed herein may have similar sizes and/or compactness in comparison to known monolithic honeycomb block reactors.

As used herein, the term “process chamber” refers to a chamber, vessel, container (e.g., hollow container) and/or enclosure that encloses materials and/or structures used to process, treat, filter and/or react with a fluid (e.g., process fluid, process byproduct, etc.) such as a liquid or gas, for example, that flows therethrough. As described in the examples disclosed herein, the process chambers may be of any appropriate shape and have any arrangement of trays to process the fluid. In particular, the trays of the process chamber may be arranged in a vertical configuration relative to one another (e.g., in series or sequential arrangement), in a horizontal arrangement to one another (e.g., in parallel to one another, etc.), a diagonal arrangement, any other appropriate spatial arrangement, or any combination of the aforementioned positional arrangements.

As used herein, the term “bulk material” refers to discrete bulk material, which may be numerous objects (e.g., grains, flakes, pellets, balls, disks, saddles and/or rings etc.) that are placed and/or randomly distributed (e.g., stacked and/or piled) in a container or vessel, and in which fluid (e.g., liquid and/or gas) may flow around, through, within or between. The bulk material, for example, may include, but is not limited to, discrete pieces (e.g., grains) of irregular and/or regular shaped solid material, saddle-type, ball-type, disk-type or ring-type material and/or ground material, etc. The bulk material may consist of grains of a specified size, a distribution of sizes and with or without specified shapes, for example. In particular, the bulk material may be composed of ceramic, glass or glass-like materials, plastics, catalyst material and/or treated to be catalytically active (e.g., crystallization, vapor deposition and/or other coating or plantation techniques, etc.). The bulk material further may comprise or consist of catalytic and/or catalytically activated material, in which catalytic material is catalytically active in some chemical regime by itself, whereas catalytically activated material is or consists of a base material that is treated to become catalytically active in some chemical regime. The “catalytic activation” can thereby comprise of a doping process (e.g. addition of a catalyst to the base structure of the bulk material) and/or a surface treatment process (e.g. surface deposition, coating, depletion, etc.) and/or chemical, electrochemical, and/or some other conversion process to increase a catalytic activity of the underlying base material of the bulk material.

As used herein, the term “flow director” refers to a geometric feature or a device or structure to divide and/or re-direct fluid flow. A geometric feature may include, but is not limited to, an annular gap, a shape of a vessel, a guide, etc. A device or structure may include, but is not limited to, openings, pipes, valves, flaps and/or guiding elements such as spoilers, baffles, ducts, orifices or deflecting plates, etc.

As used herein, “treating a fluid” may refer to processing, reducing compounds and/or purifying a fluid by physical principles (e.g., absorption, adsorption, filtration, thermal diffusion, gravity, inertia, heat transfer, electric and/or magnetic forces), a chemical (e.g., a reactant, a catalyst) and/or a chemical reaction (e.g., a catalytically supported chemical reaction), for example. As used herein, “treating a fluid” may also refer to a treatment of a fluid that may involve a change of an overall chemical composition of the fluid, filtration, fractioning and/or separation, etc.

As set forth herein,FIG. 1illustrates an example crossflow reactor100in accordance with the teachings of this disclosure. The example crossflow reactor100includes a process chamber (e.g., a housing, a vessel, an enclosure, an outer surface, etc.)102, an inlet (e.g., a fluid inlet)104, outlet(s) (e.g., fluid outlets, exhausts, etc.)106, trays (e.g., catalyst trays, cylindrical trays with a semi-conically or tapered portion, etc.),108,110,112a bottom tray (e.g., a bottom catalyst tray)114, which are generally cylindrically-shaped in this example. The trays108,110,112,114of the illustrated example contain bulk material (e.g., randomly distributed material). The bulk material stored within the trays108,110,112,114may be saddle-type, ball-type catalyst, disk-type, ring-type catalyst, and/or any other appropriate type of solid bodies. In some preferred examples, the bulk material consists of or comprises a bulk catalyst and/or a catalytically activated bulk material. In this example, the trays108,110,112are substantially identical from a geometric perspective (e.g., the same design and/or dimensions, etc.).

The trays108,110,112,114of the illustrated example each have top surfaces116,118,120,122, respectively, each of which is perforated to allow fluid to flow therethrough. In this example the top surfaces116,118,120,122are removable covers. The example trays108,110,112have a generally cylindrical shape with a semi-conical taper and define respective annular gaps123,124,125, respectively, around their periphery with respect to the chamber102. In this example, the trays108,110,112are in fluid communication with a central return (e.g., a central pipe)126via openings (e.g., cross flow openings, return openings, etc.)128,130,132, respectively. In this example, the central return has a bottom surface (e.g., exit opening(s))134in fluid communication with the outlet(s)106. The bottom tray114of the illustrated example also has a bottom perforated surface136to allow fluid to flow therethrough and does not have an annular gap in contrast to the trays108,110,112(e.g., the top surface122is sealed to an inner wall of the process chamber102). The central return126of the illustrated example is one example of a flow collector or return.

In operation, fluid (e.g., process fluid, process gas, process liquid, etc.) is provided to the inlet104and flows generally in a direction downward towards the outlet106. Consequently, at least a first fluid partial stream (e.g., a first portion, a first divided stream, etc.) divided from the inlet flow moves towards the top surface116of the first tray108, thereby flowing into the tray108via perforations, grating and/or any type of opening(s) present on the top surface116to allow the fluid to flow therethrough and then through catalyst material contained within the tray108to process the fluid. An arrow138generally indicates a flow direction of the first fluid partial stream. After the first fluid partial stream flows through the top tray108and is treated by the catalyst material, the first fluid partial stream is then directed towards the central return126via the opening128. While the first fluid partial stream flows is divided from the inlet flow, a second fluid partial stream of the fluid is also divided from the inlet flow and bypasses the first tray108by flowing around the first tray108as generally indicated by the arrow140, thereby flowing through the annular gap123and towards the tray110.

The second fluid partial stream is then further divided into additional third and fourth fluid partial streams. Similar to the flow division corresponding to the top tray108, the third fluid partial stream flows into the tray110to pass through catalyst material within the tray110and enter the central return126via the opening130, as generally indicated by an arrow142, while the fourth fluid partial stream bypasses the tray110and flows through the annular gap124surrounding the second tray108towards the tray112, as generally indicated by an arrow144. In this example, dividing the overall fluid flow into the second and fourth partial streams through the trays108and110, respectively, enables relatively equal flows through the trays108and110, thereby allowing more efficient flow through the crossflow reactor by reducing pressure drops that would have been encountered if the inlet flow and/or the partial streams had not been subdivided.

In some examples, subdividing partial streams allows at least a portion of adjacent trays to have substantially similar flow rates. Additionally or alternatively, subdividing the fluid flow may result in substantially similar flow rates throughout the entire crossflow reactor (e.g., a topmost tray has a substantially similar flow rate to a tray at the bottom). As used herein, “substantially similar” means that a volumetric flow rate, fluid velocity or pressure ratio between two fluid flow partial streams, which may be adjacent or not, may be equal to a range of approximately 0.5 to 1.5, preferably to a range of approximately 0.75 to 1.25, and even more preferred to a range of at least 1.0±10% or better.

In contrast to substantially similar flow rates through individual trays of the crossflow reactor100disclosed herein, in some alternative applications of the invention defined and/or definable and/or adjustable flow rates ratio among the individual trays of the crossflow reactor100might be beneficial. Adjustable flow rates will especially allow for a better control of the overall performance of the crossflow reactor100if performance characteristics of the individual trays evolve with some spread and/or non-homogeneously over time. In addition, individual trays maybe shut down from processing incoming fluid by a mechanical device (e.g., a bypass valve), for example, to adjust the flow ratios to allow for individual maintenance of this tray, especially bulk material inside this tray (e.g. cleaning and/or reactivation process to be applied to the bulk material, replacement of the bulk material, etc.).

Similarly, a fifth partial stream of the illustrated example flows into the tray112, as generally indicated by an arrow146, and a sixth partial stream bypasses the tray112and flows through the annular gap125surrounding the third tray112, as generally indicated by an arrow148, and towards the top surface122of the bottom tray114, which does not have an annular gap with respect to the chamber102. The sixth partial fluid stream then flows towards the bottom tray114and through the bulk catalyst material contained within the bottom tray114and through the bottom surface136, as generally indicated by an arrow150. The sixth partial fluid stream exits out of the crossflow reactor100via the outlets106. In particular, the flow exiting the bottom tray114combines with a flow from the central return126.

In some examples, the ratio between each of the diameter of the trays108,110,112to an inner diameter (e.g., an interior diameter, a chamber diameter etc.) of the chamber102may range from 0.6 to 0.99, preferably from 0.8 to 0.99. The amount of flow directed into annular gaps surrounding the trays may differ based on the perforations and/or gratings used on the inlet top surfaces116,118,120,122of the trays108,110,112,114, respectively, and/or the bottom surface134of the tray114. It has been generally observed that a substantially similar flow results from dividing the partial streams around or through the trays108,110,112, through the bottom tray114and/or through the return126. In particular, in some examples, a flow rate ratio between an annular gap of a tray and the amount flowing through the respective tray may range from 0.2 to 1. In some examples, a flow rate ratio may be approximately 0.25 (e.g., 25% of the flow flows into the tray and 75% flows into the respective annular gap around the tray). The ratios described are only illustrative examples and may vary accordingly. The flow rate ratios per tray may or may not depend on the number of trays in a special embodiment according to the present examples and, thus, the examples disclosed herein are not limited to the number of trays shown in the illustrated examples. While the partial streams are shown being divided into sequential trays, in some examples, the partial streams may be directed to non-sequential trays (e.g., a partial stream bypasses a first tray and then is directed to a fourth tray in sequence via a conduit and/or flow re-director, etc.).

In some examples, the trays108,110,112,114have similar or the same heights and/or amounts of catalyst contained within. In other examples, the trays108,110,112,114have differing heights and/or amounts of catalyst contained within to maintain a relative determination of the filling height (e.g., the tray114has an approximately 2-10% higher filling height than the trays108,110,112, etc.). In this example the trays108,110,112have approximately 1150 mm in height of bulk material (e.g., bulk catalyst material) while the tray114has approximately 1225 mm in height of bulk material (e.g., bulk catalyst material). The dimensions shown in the illustrated examples are only dimensions and, thus, may vary greatly with respect to an application and/or a specific process.

By dividing the flow into partial streams and directing the partial streams toward different trays, the crossflow reactor100allows effective flow (e.g., relatively low loss flow) through the trays108,110,112,114without significant pressure losses along an overall length of the crossflow reactor100. Separating the bulk material (e.g., bulk catalyst material) into separate trays allows significantly less pressure-loss along a corresponding length of the crossflow reactor100and avoids crushing of the bulk material catalyst, which can further lead to additional pressure loss and/or velocity loss of the fluid. In particular, a critical height to weight ratio is met to prevent the catalyst material from crushing. It has been determined that in some examples, a desirable range of height to weight may range from 0.0 to 2.0. The central return126of the illustrated example also facilitates reduction of pressure losses by providing a relatively low-loss central conduit for fluid to flow therethrough once the fluid has passed and/or been processed through the trays108,110and112.

While each of the trays108,110,112of the illustrated example define substantially uniform annular gaps relative to the chamber102, in other examples, the annular gaps surrounding the trays108,110,112may vary (e.g., narrow or widen) along a longitudinal length of the crossflow reactor100and/or the annular gaps around the trays108,110112may be different from one another. While annular gaps of the illustrated example are used as distribution devices to re-direct or divide the flow into partial streams, any appropriate type of flow director may be used to divide the partial streams and/or direct the partial streams towards their respective trays108,110,112and/or114. Some examples may use distribution devices including, but not limited to, openings, pipes, valves, flaps and/or guiding elements such as spoilers, baffles, ducts, orifices or deflecting plates, etc. While the trays108,110,112are generally identical in this example, the geometries, shapes, sizes, types and/or quantities of the trays108,110,112may vary relative to one another. In particular, the trays108,110,112and/or114may have varying geometries and/or have differing amounts of bulk material (e.g., bulk catalyst material) within to more evenly distribute flow between the trays108,110,112and/or114.

FIG. 2Aillustrates a cross-sectional view of the example tray108and a portion of the example return126of the example crossflow reactor100ofFIG. 1. As described above in connection withFIG. 1, the tray108has a top surface116, which is perforated in this example. The tray108of the illustrated example also has an outer cylindrical wall202defining a catalyst storage compartment206, a grated platform208, a second perforated surface209, a conical portion210, which is in fluid communication with a return chamber212(e.g., a central opening of the return126, etc.) via the opening128. While the return212of the illustrated example is shown in a central location of the reactor100, the return212may be located off-center or any appropriate position within the reactor100. The return chamber212of the illustrated example is another example of a flow collector or return.

In this example, the perforated top surface116prevents the bulk material (e.g., bulk catalyst material) stored in the catalyst storage compartment206from flowing and/or displacing out of the tray108. In some examples, ball-type catalyst contained within the tray108may be approximately ⅛″ to 3/16″ in size and light enough to come out of the tray108with even minimal fluid movement or fluctuations of fluid within and, thus, the top surface116prevents the catalyst from flowing out of the tray108. The grated platform208of the illustrated example has the perforated surface209positioned above in the orientation of the viewing direction ofFIG. 2A. The perforated surface209may have a perforation pattern, which is similar or identical to the grated top surface116, to prevent the bulk material (e.g., bulk catalyst material) of the storage compartment206from flowing into the central return212. In other examples, the perforated surface209is below the grated platform208. In some examples, the grated platform208provides mechanical and/or structural support for the bottom perforated surface209. In some examples, the central return126, the grated platform208and/or the perforated surface209is coupled (e.g., welded) to the tray108, for example.

In operation, a partial fluid stream flows into the tray108through perforations of the top surface116and towards the conical section210in a direction generally indicated by an arrow214and into the central return opening212via the opening128, as generally indicated by an arrow216. In particular, the partial fluid stream enters the tray108via openings (e.g., perforations, gratings, circular openings and/or rectangular openings, hexagonal openings, etc.) of the top surface116, passes through the bulk material (e.g., bulk catalyst material) stored within in the catalyst storage compartment206and then passes through the perforated surface209and through the grated platform208to enter the conical section210, which does not contain bulk material (e.g., bulk catalyst material) in this example. After the partial stream flows into the central return212, the partial stream heads downward through the central return212towards the outlets106. The height and/or width of the catalyst storage compartment206of the illustrated example may be designed and/or specified to meet necessary requirements for the catalyst material (e.g., height to weight ratio, necessary residence time and/or maximum allowable pressure drop requirements, etc.).

In this example, to maintain height to diameter ratio of the tray108at approximately 0.7, the tray108is sized to approximately 2000 mm (millimeters) in overall height and has an approximate diameter of 2800 mm. While the tray108is shown as semi-conical or cylindrical shape, any appropriate shape may be used including, but not limited to, rectangular, spherical, cylindrical, parallelogram, etc. In some examples, the tray108of the illustrated example may have a discharge device (e.g., a drain), a filling device (e.g., another inlet), a heating or cooling device, and/or a regeneration device. In some examples, the tray108may route the partial stream within the storage compartment206, to another tray, to an inlet device, to a distribution device (e.g., a fluid distribution device), and/or to be cooled and/or heated. In some examples, fluid within the tray108and/or external to the tray108is measured and/or controlled for concentrations of compounds to be removed, etc.

FIG. 2Billustrates a partial cross-sectional view of the reactor100ofFIG. 1along a longitudinal direction of the reactor100. As can be seen from this view, the chamber102and the outer cylindrical wall202of the tray108define the annular gap123to allow a partial fluid stream to flow therethrough.

In this example, the grated platform208has wider openings than perforations on the top surface116and/or the perforated surface209adjacent the grated platform208. Further, the grated platform208of the illustrated example has relatively greater thickness than the perforated top surface116and the perforated surface209. In some examples, the perforations of the top surface116and/or the perforated surface209may be square-shaped, hex-shaped, oval-shaped, slot-shaped, triangular shaped, pentagonal shaped or honeycomb shaped, etc.). In some examples, the diameter of the central return212varies along the length of the crossflow reactor100.

FIG. 3illustrates a cross-sectional view of another example crossflow reactor300in accordance with the teachings of this disclosure. The example crossflow reactor300includes a chamber (e.g., a housing, an enclosure, a process chamber, etc.)302, an inlet304, an outlet306, and a tray assembly308. In this example, the tray assembly308includes storage trays (e.g., annular shaped storage trays, annular ring shaped storage trays, etc.)312,316,318,320,322,324and defines a central return (e.g., a central channel)311. In this example, the tray assembly also includes mechanical mounts and/or parts (e.g., mounting struts, lips and/or flanges on top of the trays312,316,318,320,322,324) to support the trays312,316,318,320,322,324in a vertical stack and/or to mount the trays312,316,318,320,322,324to the chamber302. The bulk material (e.g., bulk catalyst material) storage trays312,316,318,320,322,324going in a direction downward as viewed in the orientation ofFIG. 3, have increasing diameters and, thus, a decreasing annular gap326with respect to the chamber302in a downward direction of the orientation shown inFIG. 3. In some examples, an annular gap is relatively constant or increases instead in a direction towards an outlet. Additionally, in this example, the central return311increases in diameter in the indicated downward direction. In some examples, the central return may be relatively constant or even decrease in diameter instead.

The bulk material (e.g., bulk catalyst material) storage trays312,316,318,320,322,324of the illustrated example store bulk material, which are ring-type catalyst in this example. Other bulk material, (e.g., bulk catalyst material) configurations may be used. Each of the bulk material (e.g., bulk catalyst material) storage trays312,316,318,320,322,324of the illustrated example have perforated outer annular surfaces328,330,332,334,336,338, respectively, to allow the fluid in the annular gap surrounding the trays312,316,318,320,322,324to enter therethrough and be processed by bulk material (e.g., bulk catalyst material). The trays312,316,318,320,322,324of the illustrated example also have inner annular surfaces340,342,344,346,348,350, respectively, which are also perforated.

In operation, fluid (e.g., process fluid) enters the inlet304and then the fluid flows through the annular gap326and is subdivided into partial fluid streams that flow towards and into the trays312,316,318,320,322,324, thereby distributing the fluid flow through multiple trays via the partial fluid streams to reduce pressure losses and/or bulk material, (e.g., bulk catalyst material) crushing, for example. Arrows360of the illustrated example generally indicate flow paths into the trays312,316,318,320,322,324. Each partial stream enters the trays312,316,318,320,322,324via the outer annular surfaces328,330,332,334,336,338, which are perforated in this example, and passes through the respective bulk material (e.g., bulk catalyst material) storage areas to be processed by the bulk material (e.g., bulk catalyst material) stored within. The partial streams then pass though the respective inner annular openings340,342,344,346,348,350of the respective trays to enter the central return311, in which the partial streams combine and exit the crossflow reactor300via the outlet306. In some examples, the trays312,316,318,320,322,324and/or a portion thereof may be in fluid communication with one another (e.g., there may be perforated surfaces between the stacked trays312,316,318,320,322,324).

Similar to the crossflow reactor100ofFIG. 1, the crossflow reactor300allows separate trays of catalyst to receive partial streams to avoid significant pressure and/or velocity losses of the overall flow. Additionally, maintaining the bulk material (e.g., bulk catalyst material) with a specific height to weight ratio such as a ratio of 0.0 to 2.0, for example, reduces and/or eliminates crushing of the bulk material (e.g., bulk catalyst material).

FIG. 4Ais a cross-sectional view of an example tray312of the crossflow reactor300ofFIG. 3along a longitudinal direction of the crossflow reactor300. As described above in connection withFIG. 3, the tray312of the illustrated example includes the outer annular surface328, which is perforated in this example, an inner perforated annular surface340that defines the inner chamber (e.g., central return, return pipe, etc.)311, and spans (e.g., supports, span supports, etc.)406, which couple (e.g., structurally couple, mechanically couple, etc.) the outer annular surface328to the inner annular surface340. The outer annular surface328, the spans406and the inner annular surface340define bulk material storage areas411where bulk material (e.g., bulk catalyst material, ring-type catalyst) is stored. In some examples, the spans406are perforated. The perforated surfaces of the outer annular surface328and the inner annular surface340allow a radial cross flow from the outer annular surface328to the inner chamber311, which is a central return to the outlet306in this example.

FIG. 4Bis another cross-sectional view of the example tray312ofFIG. 3along a line A-A ofFIG. 4A. In this view, the central chamber311and the bulk material storage areas (e.g., bulk catalyst material storage areas)411are shown. Additionally, a top surface (e.g., a removable top surface)412of the illustrated example is generally flat and does not have perforations or grating, thereby directing the cross flow of the fluid in a generally radially inward direction (e.g., crossflow towards the center of the tray312, etc.), in contrast to the at least partial vertical flow shown above in connection with the example reactor100described above in connection withFIG. 1. In this example, the tray312has a height of approximately 800 mm (millimeters), a diameter of about 2750 mm and an inner diameter of approximately 950 mm, but these dimension may vary in other examples and are only mentioned for this illustrative example.

FIG. 4Cis a detailed view of the outer annular surface328of the example tray312ofFIG. 3. In this example, perforations414of the outer annular surface328are approximately 8 mm long with a corresponding radius of 2 mm. In some examples, perforations may be spaced approximately 4 mm apart from one another. In some examples, the positions and/or spacing of the perforations414may vary along different directions of the tray312to control the flow through the tray312. The perforations on the inner annular surface340may also have similar dimensions. In order to select appropriate perforation sizes (e.g., perforation diameters) for a certain type of bulk material, in some examples, it is common to take into account bulk material size distribution (e.g., the smallest diameter of the bulk material) and/or pressure distributions, etc.

In some examples, the size and/or spacing of the perforations of the inner annular surface340may vary from the outer annular surface328to control the reaction (e.g., residence time, laminarity of the flow and/or flow distribution, etc.) of the fluid flowing through the bulk material contained in the bulk material (e.g., bulk catalyst material) storage areas411. While certain example dimensions are described above, any appropriate dimension, geometric arrangement, spatial arrangement and/or opening geometry may be used for any of the perforations or grating.

FIG. 5is an example of another example crossflow reactor500, which is operated in a horizontal orientation. The crossflow reactor500of the illustrated example includes an inlet channel502leading to an enclosure504, an outlet channel506leading out of the enclosure504and trays508,510disposed within the enclosure504. The tray508has a top surface520and a bottom surface524. Likewise, the tray510has a top surface526and a bottom surface528.

In operation, fluid to be treated by the cross flow reactor500is provided to the inlet channel502and flows towards outlets530,532and into the trays508,510to be treated by bulk material stored therein. In this example, the inlet channel502has a decreasing cross-section in a direction towards the outlet532. As the fluid moves out of the outlet530, it passes through the top surface520, which may be perforated or have a single opening, for example, and into the tray508where it is treated by bulk material in the tray508. Likewise, fluid from the outlet532flows into the tray510via the top surface526to be treated by bulk material in the tray510. The treated fluid from the trays508,510exits through the bottom surfaces524,528of the trays508,510, respectively and flows into the outlet channel506in which the treated fluid exits the example crossflow reactor500.

FIG. 6is an example of another example crossflow reactor600, which is similar to the example crossflow reactor100ofFIG. 1, but in a horizontal configuration. In contrast to the crossflow reactor100, the example crossflow reactor600has an inlet602leading to an enclosure (e.g. a housing a vessel, etc.)604and an outlet606exiting the enclosure604. In this example, the inlet602and the outlet606are substantially parallel to a general direction of flow through the enclosure604. In contrast to the crossflow reactor100, the crossflow reactor has one or more conduits608with conduit inlets610and conduit outlets611leading to trays612that contain bulk material to treat the fluid and fluidly communicate with a return613that is capped near the inlet602and open near the outlet606. The conduits608also include an outlet614for fluid to flow into a final tray616with a perforated exit surface618. In this example, the conduits608have a decreasing cross-section and/or diameter in a direction towards the outlet606.

In operation, fluid flows into the inlet602and flows into the conduits608via the inlets610. The fluid then flows through the conduits608and a portion of the fluid flows through the trays612to be treated by the bulk material contained within each of the trays612. Another portion of the fluid flows to the outlet614, into the final tray616, which also contains bulk material, and out of the final tray via the perforated exit surface618to converge with fluid from the return613before exiting the crossflow reactor via the outlet606.

In this example, the trays612,614are filled and/or partially filled with the bulk material prior to being placed into the crossflow reactor600. Additionally or alternatively, the trays612,614have accessible doors (e.g., maintenance doors) to access and/or service the bulk material in the trays612,614while the trays612,614are within the enclosure604. Additionally or alternatively, the enclosure604has openings (e.g., doors, access doors, etc.) to access the trays612,614and/or access doors of the trays612,614. While the trays612,614of the illustrated example have a substantially round shape, in some examples, the trays612,614have a rectangular shape.

FIG. 7is a flow diagram of an example method in accordance with the teachings of this disclosure. The example process700ofFIG. 7begins when a fluid from an industrial process (e.g., combustion, steam-driven by combustion, etc.) is to be treated (e.g., processed through catalyst material, etc.) (block702). The fluid is provided to a process chamber (e.g., the process chamber102, the process chamber302, the process chamber504, the process chamber604) via an inlet (e.g., the inlet104, the inlet304, the inlet channel502, the inlet602, etc.) of the process chamber (block704).

The flow is then divided into partial streams (block706). The division of the partial streams may occur through annular gaps around trays of the process chamber such as shown with the example crossflow reactors100and300, for example. In this example, at least two of the partial streams directed to adjacent trays have predefined, adjusted and/or adjustable flow rates and/or flow ratios. In some examples, devices such as baffles, pipes and/or flow redirectors, etc. are used to divide and/or further direct the partial streams. In some examples, the general positions of the trays of the process chamber relative to one another define the flows and/or division of the flows into partial streams (e.g., trays positioned parallel to one another, etc.).

The partial streams are then directed to their respective trays (block708). In particular, the partial streams of the fluid flow are moved into their respective trays to be treated by flowing through bulk material (e.g., bulk catalyst material) contained within the trays, for example.

In some examples, at least a portion of the partial streams, after flowing through their respective trays, are directed to a return such as the central return212ofFIG. 2A, the central return311ofFIG. 3, or the central return613ofFIG. 6(block710). In some examples, the partial streams that have flowed through their respective trays are then combined prior to exiting the process chamber into a combined exit flow (block712). In some examples, the combined exit flow is directed towards an outlet of the process chamber (block714). Next, it is determined if the process should end (block716). If the process is determined to end (block716), the process ends (block718). Alternatively, if the process is not determined to end (block716), the process repeats (block702).

From the foregoing, it will appreciate that the above disclosed methods and apparatus enable crossflow reactors that use inexpensive bulk material to treat fluids with minimal pressure and/or velocity losses.