US20250334284A1

US20250334284A1 - Rotor for an air conditioning system with a plurality of sorbent sections

Info

Publication number: US20250334284A1
Application number: US18/644,551
Authority: US
Inventors: Amit Gitterman
Original assignee: Munters Corp
Current assignee: Munters Corp
Priority date: 2024-04-24
Filing date: 2024-04-24
Publication date: 2025-10-30

Abstract

An air conditioning system includes a rotor that may include a hydrophilic section and a hydrophobic section, and process air of a process air stream may flow though the hydrophilic process segment in series with the hydrophobic process segment. The rotor may include an inner core and an outer annulus. The outer annulus is arranged radially outward of the inner core and may be rotatable independently from the inner core. The hydrophilic section may be one of the inner core and the outer annulus, and the hydrophobic section may be the other one of the inner core and the outer annulus.

Description

FIELD OF THE INVENTION

The invention relates to air conditioning systems, equipment, and methods, particularly rotary based sorbent conditioning systems.

BACKGROUND OF THE INVENTION

Air may be conditioned in a sorption process to remove various compounds from the air. Some such air conditioning systems use a sorbent to remove various molecules from an airstream to condition the airstream. The sorbents may be arranged in a rotor to rotate between various zones, such as a process zone where the sorbent removes molecules from process air flowing through the sorbent in the process zone and a regeneration zone where a regeneration airstream removes the molecules from the sorbent to regenerate the sorbent. One example is dehumidification, where the sorbent is a desiccant and the desiccant is used to remove water, such as water vapor, from the process air. Other sorbents may be used to target and remove other gases, including for example, carbon dioxide, ammonia, hydrogen sulfide, and volatile organic compounds (VOCs).
To prevent the moisture content of the process being conditioned from degrading the carbon-compound abatement process, the air can be directed through a dehumidifier prior to the carbon-compound abatement process. The air conditioning system can use, for example, two rotors in series. The first rotor (an upstream rotor) can include a desiccant as the sorbent to remove moisture from the air, and a second rotor (a downstream rotor) can be used for carbon-compound abatement. In this way, the air stream flowing to the downstream rotor can be maintained at optimal inlet conditions to maximize the carbon compound adsorption capacity of the diffusion sites on the rotor surfaces.

SUMMARY OF THE INVENTION

In one aspect, the invention relates to an air conditioning system for conditioning process air of a process air stream. The air conditioning system includes a rotor with a hydrophilic section and a hydrophobic section. The hydrophilic section has a hydrophilic sorbent and a hydrophilic process segment through which the process air stream is directed. The hydrophobic section has a hydrophobic sorbent and a hydrophobic process segment through which the process air stream is directed. The process air of the process air stream flows though the hydrophilic process segment in series with the hydrophobic process segment, and the process air flows through the hydrophilic process segment before the hydrophobic process segment.
In another aspect, the invention relates to an air conditioning system including a rotor. The rotor includes an inner core and an outer annulus. The inner core has an inner core process segment through which process air from a first process air stream is directed and an inner core regeneration segment through which regeneration air from a first regeneration air stream is directed. The inner core contains a sorbent that is rotatable between the inner core process segment and the inner core regeneration segment. The outer annulus has an outer annulus process segment through which process air from a second process air stream is directed and an outer annulus regeneration segment through which regeneration air from a second regeneration air stream is directed. The outer annulus contains a sorbent that is rotatable between the outer annulus process segment and the outer annulus regeneration segment. The outer annulus is arranged radially outward of the inner core and is rotatable independently from inner core.
These and other aspects of the invention will become apparent from the following disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of an air conditioning system that includes a sorption rotor according to a preferred embodiment.

FIG. 2 shows an arrangement of ductwork of plenums for the sorption rotor shown in FIG. 1 illustrating an arrangement of seals.

FIG. 3 is a schematic of another sorption rotor that can be used in place of the sorption rotor of the air conditioning system of FIG. 1 .

FIG. 4 is a schematic of another sorption rotor that can be used in place of the sorption rotor of the air conditioning system of FIG. 1 .

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As used herein, the terms “upstream” and “downstream” are taken with respect to the flow of a fluid in a fluid pathway, such as, for example, the flow of process air in the air conditioning system.
As discussed above, air conditioning systems may include a rotor-based sorbent that is used to remove various molecules including carbon compounds from air. The air from which the carbon compounds are being removed is referred to herein as process air. Carbon abatement systems can use, for example, zeolite as the sorbent or amine-based sorbent systems. These sorbents can be hydrophobic, but excess moisture content in the process air can decrease the efficiency of carbon-compound removal. Without intending to be bound to any theory, this decrease in efficiency can result from condensation of the water in the air. Moisture in the process air may condense and this condensate occupies the adsorption sites of the carbon-compound sorbent, degrading the efficiency of the abatement process. Moisture loads on the sorbent media may form clusters around the adsorption sites, creating a diffusion block for abatement of carbon-compound molecules.
As noted above, the process air can be directed through a dehumidifier prior to the carbon-compound abatement process to prevent the moisture content of the process air from degrading the carbon-compound abatement process. With separate systems, units, or rotors for the dehumidification and then carbon abatement, these systems can be large and complex. The air conditioning systems discussed herein advantageously reduce the overall footprint and complexity of the air conditioning system by utilizing a single rotor with at least two different sorbent sections instead of two separate rotors or systems. This single rotor can be heated using a single airstream for both sorbent sections.
FIG. 1 is a schematic of an air conditioning system 100 that includes a sorption rotor 200 according to a preferred embodiment. The air conditioning system 100 can be used to condition air and, more specifically, as depicted in FIG. 1 , remove carbon compounds from the air. The air being conditioned and from which the carbon compounds are being removed is referred to herein as process air 12, and the air conditioning system 100 includes a process airflow. The air conditioning system 100 can provide the conditioned air, as supply air, to a space, such as a room. The air being conditioned (i.e., the process air 12) can be drawn from various suitable sources including ambient air outside of the room or recirculated air (return air) from within the room. In another example, the process air 12 can be drawn from an industrial or commercial process, and after the carbon compounds are removed, the process air 12 is exhausted to ambient. The air conditioning system 100 includes a process air plenum 110 through which the process air 12 flows. The process air 12 enters the process air plenum 110 via a process air inlet 112, flows through the process air plenum 110, where, as discussed in more detail below, the process air 12 is dehumidified and the carbon-compounds are abated. After being conditioned, the process air 12 then flows out of the process air plenum 110 via a process air outlet 114.
The sorption rotor 200 includes a rotor axis 201 about which the sorption rotor 200 rotates. The rotor axis 201 defines an axial direction A of the sorption rotor 200. The sorption rotor 200 also has a radial direction R, and a circumferential direction C. The radial direction R is perpendicular to the axial direction A and extends in a direction outward from the rotor axis 201. The circumferential direction C extends in a direction rotating about the rotor axis 201. The sorption rotor 200 is a circular-cylindrical shape and, more specifically, disk shaped with a length in the axial direction, which is referred to herein as a thickness, that is much smaller than the diameter of the sorption rotor 200.
The sorption rotor 200 includes a plurality of sections, each containing a sorbent. The sorption rotor 200 shown in FIG. 1 includes two sections, an inner core 210 and an outer annulus 230. One of these sections is a desiccant section 212 having a desiccant as the sorbent. Suitable desiccants include, for example, titanium silica gel and lithium chloride. Such desiccants can be arranged in a porous structure through which air can flow. This porous structure can include, for example a honeycomb structure or other fluted structure including a plurality of flutes and a plurality of flow channels through which air can flow. The desiccant can be impregnated into these structures forming the flow channels or coated on the surfaces defining the flow channels.
A portion of the sorption rotor 200 is located in the process air plenum 110 and positioned to allow the process air 12 to flow through the desiccant in the desiccant section 212 of the sorption rotor 200 located within the process air plenum 110. The portion of the process air plenum 110 in which the desiccant is located is a dehumidification section 116 of the air conditioning system 100, and the portion of the sorption rotor 200 and, more specifically, the desiccant section 212 through which the process air 12 flows is referred to as the dehumidification process segment 221 (or dehumidification process zone) of the sorption rotor 200. The process air 12 flows through the dehumidification process segment 221 and moisture from the process air 12 is adsorbed by the desiccant in the dehumidification process segment 221, dehumidifying the process air 12. In the dehumidification process segment 221 (the dehumidification section 116), the surface vapor pressure of water of the desiccant is lower than the process air 12 allowing the desiccant to adsorb moisture from the process air 12. The desiccant is a hydrophilic sorbent. The desiccant section 212 thus may be referred to herein as a hydrophilic section 214, and the dehumidification process segment 221 is a hydrophilic process segment 223 through which process air 12 of the process air stream is directed. The discussion of the dehumidification process segment 221 also applies to the hydrophilic process segment 223 unless otherwise noted.
The second section of the sorption rotor 200 is a carbon-abatement section 232 having a sorbent that can adsorb carbon compounds. Such carbon compounds include, for example, VOCs, carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate. The sorbent is chosen based on the carbon compound being targeted, and to distinguish from the desiccant, this sorbent is referred to as a carbon-abatement sorbent. When carbon dioxide is being removed from the process air 12, for example, the carbon-abatement sorbent can be silicates, such as zeolite, polymeric sorbents and amines. Suitable polymeric sorbents include, but are not limited to, polyethylene glycol (PEG), polyvinylamine (PVA), poly(acrylonitrile-co-vinylimidazole) (PANVI), or mixtures thereof. Suitable amines include organic amines. Amine-based sorbents include, but are not limited to, polyethylenimine (PEI), aziridine, ethanolamine, monoethanolamine (MEA), diethanolamine (DEA), diglycolamine (DGA), methyldiethanolamine (MDEA), diisopropanolamine (DIPA), triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, or mixtures thereof. The inventor has found that branched polyethylenimine (BPEI) can be particularly effective in carbon dioxide scrubbing and would be effective in a rotary scrubbing system. Other amine-based sorbents include amine-functionalized silicas such as amine-functionalized Santa Barbara Amorphous-15 (SBA-15). At least some of these carbon-abatement sorbents are hydrophobic.
The “liquid wettability,” or “wettability,” of a solid surface may be determined by observing the nature of the interaction occurring between the solid surface and a drop of a given liquid disposed on the surface. A high degree of wetting results in a relatively low solid-liquid contact angle and large areas of liquid-solid contact. Conversely, a low degree of wetting results in a relatively high solid-liquid contact angle with the liquid forming droplets on the surface. The hydrophilicity or hydrophobicity of a sorbent may be characterized by the degrees of wettability on the sorbent, and in the embodiment discussed herein that include channels in the sorption rotor 200, the degrees of wettability for a water droplet on the surface defining the channel. In general, hydrophilic sorbents have contact angle less than 90 degrees, and hydrophobic sorbents have a contact angle at or above 90 degrees. Some sorbents discussed herein may be considered a quasi-hydrophobic sorbent. A quasi-hydrophobic sorbent is a hydrophobic sorbent with a contact angle making it hydrophobic (i.e., contact angle at or above 90 degrees), but only having a small degree of hydrophobicity, such as a contact angle of 113 degrees or less. Quasi-hydrophobic sorbents may thus have a contact angle from 90 degrees to 113 degrees. Preferably, the hydrophilic sorbents discussed herein have a contact angle less than or equal to 69 degrees, and the hydrophobic sorbents have a contact angle greater than or equal to 113 degrees. Alternatively, the hydrophilic sorbents and the hydrophobic sorbents may be determined relative to each other, with the hydrophilic sorbent having a contact angle that is less than the contact angle of the hydrophobic sorbent. This is referred to herein as relative hydrophilicity/hydrophobicity or relative wettability. The difference in contact angle between the hydrophilic sorbent and the hydrophobic sorbent may be at least 10 degrees, such as at least 20 degrees. When the hydrophilic sorbents and the hydrophobic sorbents are determined by relative wettability, both the hydrophilic sorbent and the hydrophobic sorbent may have contact angles that are less than 90 degrees or have contact angles that are at or above 90 degrees.
A portion of the sorption rotor 200 is located in the process air plenum 110 and positioned to allow the process air 12 to flow through the carbon-abatement sorbent in the carbon-abatement section 232 of the sorption rotor 200 located within the process air plenum 110. As with the desiccant, the carbon-abatement sorbent can be arranged in a porous structure through which air can flow. This porous structure can include, for example, a honeycomb structure or other fluted structure forming a plurality of flow channels through which air can flow. The desiccant can be impregnated into these structures forming the flow channels or coated on the surfaces defining the flow channels.
The portion of the process air plenum 110 in which the carbon-abatement sorbent is located is a carbon-abatement section 117 of the air conditioning system 100, and the portion of the sorption rotor 200 and, more specifically, the carbon-abatement section 232 through which the process air 12 flows is referred to as the carbon-abatement process segment 241 (or carbon-abatement process zone) of the sorption rotor 200. The process air 12 flows through the carbon-abatement process segment 241 and the carbon compounds in the process air 12 is adsorbed by the carbon-abatement sorbent in the carbon-abatement process segment 241, removing carbon compounds from the process air 12. In the carbon-abatement process segment 241 (the carbon-abatement section 117), the surface vapor pressure of carbon compounds of the carbon-abatement sorbent is lower than the process air 12, allowing the carbon-abatement sorbent to adsorb the carbon compounds from the process air 12. As noted above, the carbon-abatement sorbent can be a hydrophobic sorbent. The carbon-abatement section 232 thus may be referred to herein as a hydrophobic section 234, and the carbon-abatement process segment 241 is a hydrophobic process segment 243 through which process air 12 of the process air stream is directed. The following discussion of the carbon-abatement process segment 241 also applies to the hydrophobic process segment 243 unless otherwise noted.
The dehumidification process segment 221 (the hydrophilic process segment 223) and the carbon-abatement process segment 241 (the hydrophobic process segment 243) are arranged in series with each other relative to the flow of the process air 12 in the process air stream. As depicted in FIG. 1 , the dehumidification process segment 221 is positioned upstream of the carbon-abatement process segment 241, and the process air 12 flows through the dehumidification process segment 221 before the carbon-abatement process segment 241. In this way, the desiccant in the dehumidification process segment 221 removes moisture from the process air 12 before the process air 12 flows through the carbon-abatement sorbent in the carbon-abatement process segment 241, increasing the effectiveness of carbon adsorption. The dehumidification process segment 221 and the carbon-abatement process segment 241 can be arranged in a counter flow arrangement, as depicted in FIG. 1 , for example. The process air stream (the process air 12) is directed through the dehumidification process segment 221 (the hydrophilic process segment 223) in a dehumidification process flow direction (a hydrophilic process flow direction). The dehumidification process flow direction can be parallel to the axial direction A of the sorption rotor 200. The process air plenum 110 is ducted such that the process air 12 reverses direction and then is directed through the carbon-abatement process segment 241 (the hydrophobic process segment 243) in a carbon-abatement process flow direction (a hydrophobic process flow direction). The carbon-abatement process flow direction can be parallel to the axial direction A of the sorption rotor 200 and can be parallel to the dehumidification process flow direction.
As the desiccant adsorbs moisture from the process air 12, the ability for the desiccant to adsorb additional moisture is reduced, as the surface vapor pressure of water of the desiccant increases because of adsorption. Similarly, as the carbon-abatement sorbent adsorbs carbon-compound molecules from the process air 12, the ability for the carbon-abatement sorbent to adsorb additional carbon-compound molecules is reduced, as the surface vapor pressure of carbon compounds of the carbon-abatement sorbent increases because of adsorption. The desiccant and the carbon-abatement sorbent are thus regenerated to restore their ability to adsorb moisture and carbon-compound molecules, respectively. As used herein, this process is generally referred to as regeneration, but alternatively, this process (and corresponding systems, components, and air) may be referred to as reactivation. In this embodiment, the desiccant is regenerated using regeneration air 14 and the air conditioning system 100 includes a regeneration air stream. The regeneration air 14 can be drawn from various suitable sources including ambient air. The air conditioning system 100 includes a regeneration air plenum 120. The regeneration air 14 enters the regeneration air plenum 120 via a regeneration air inlet 122, flows through the regeneration air plenum 120 where the regeneration air 14 is used to regenerate the desiccant and the carbon-abatement sorbent, and then flows out of the regeneration air plenum 120 via a regeneration air outlet 124. The portion of the regeneration air plenum 120 in which the desiccant and carbon-abatement sorbent are located is a desorption section 126 of the air conditioning system 100.
The portion of the desiccant section 212 through which the regeneration air 14 flows is referred to as the dehumidification regeneration segment 225 (or dehumidification regeneration zone). The regeneration air 14 flows through the dehumidification regeneration segment 225 and removes moisture from the desiccant in the dehumidification regeneration segment 225, regenerating the desiccant. Within the dehumidification regeneration segment 225, the desiccant has a surface vapor pressure of water that is significantly higher than the regeneration air 14 so moisture from the desiccant is transferred to the regeneration air 14 to equalize the pressure differential. Similarly, the portion of the carbon-abatement section 232 through which the regeneration air 14 flows is referred to as the carbon-abatement regeneration segment 245 (or carbon-abatement regeneration zone). The regeneration air 14 flows through the carbon-abatement regeneration segment 245 and removes carbon-compound molecules from the carbon-abatement sorbent in the carbon-abatement regeneration segment 245, regenerating the carbon-abatement sorbent. Within the carbon-abatement regeneration segment 245, the carbon-abatement sorbent has a surface vapor pressure of carbon compounds that is significantly higher than the regeneration air 14 so the carbon-compound molecules from the carbon-abatement sorbent are transferred to the regeneration air 14 to equalize the pressure differential.
Relative to the regeneration air stream, the dehumidification regeneration segment 225 and the carbon-abatement regeneration segment 245 can have different arrangements, but in the embodiment depicted in FIG. 1 , the dehumidification regeneration segment 225 and the carbon-abatement regeneration segment 245 are arranged in parallel relative to the regeneration air stream. A first portion of the regeneration air 14, as a first regeneration air stream 16, flows through the dehumidification regeneration segment 225, and a second portion of the regeneration air 14, as a second regeneration air stream 18, flows through the carbon-abatement regeneration segment 245. The dehumidification regeneration segment 225 and the carbon-abatement regeneration segment 245 thus collectively form a rotor regeneration segment 202. The rotor regeneration segment 202 is a pie-shaped (or V-shaped) segment of the dehumidification process segment 221 extending radially outward from the rotor axis 201 over a set angle of the dehumidification process segment 221.
While the carbon-abatement section 232 is discussed above as having a hydrophobic sorbent, the sorption rotor 200 and arrangement of the flow paths discussed herein may be used with different sorbents in the carbon-abatement section 232 and still have the advantages discussed herein. For example, the carbon-abatement section 232 may have a hydrophilic sorbent or a quasi-hydrophobic sorbent. With the process air 12 flowing first through the desiccant section 212, moisture is removed before flowing through the carbon-abatement section 232, providing the advantages discussed above with respect to carbon removal from the process air 12. Additionally, although the embodiments discussed herein have been described with respect to carbon removal, the embodiments discussed herein may be used to remove other molecules and compounds from the process air, such as by using other sorbents, for example. These other compounds and molecules may be referred to herein as molecules other than water.
The various segments of the sorption rotor 200 can be separated from each other by seal assemblies that prevent the flow of air between adjacent segments (or zones) of the sorption rotor 200. Each seal assembly includes a seal, and the seal can be, for example, face seals and, more specifically, elastomeric face seals. As depicted in FIG. 1 , for example, the dehumidification process segment 221 can be separated from the dehumidification regeneration segment 225 by one or more seals, and the carbon-abatement process segment 241 can be separated from the carbon-abatement regeneration segment 245 by one or more seals. To maintain the dehumidification process segment 221 and the carbon-abatement process segment 241 in the serial flow arrangement discussed above, the dehumidification process segment 221 and the carbon-abatement process segment 241 are also separated from each other by one or more seals. As noted above, the dehumidification regeneration segment 225 and the carbon-abatement regeneration segment 245 are in the same pie-shaped segment of the sorption rotor 200, and thus a seal does not separate the dehumidification regeneration segment 225 and the carbon-abatement regeneration segment 245 from each other in the depicted embodiment. Alternatively, such as when other flow arrangements are used, one or more seals can be used to separate the dehumidification regeneration segment 225 from the carbon-abatement regeneration segment 245.
One of the desiccant section 212 or the carbon-abatement section 232 is arranged radially outward of the other one of the desiccant section 212 or the carbon-abatement section 232. In the embodiment depicted in FIG. 1 , the carbon-abatement section 232 is positioned radially outward of the desiccant section 212 and the following discussion will reference this arrangement. The alternate arrangement with the desiccant section 212 positioned radially outward of the carbon-abatement section 232 can also be used, and unless otherwise noted, the following discussion also applies to this alternate arrangement.
The sorption rotor 200 includes an inner core 210 having an inner core process segment 227 through which the process air 12 from a first process air stream is directed and an inner core regeneration segment 229 through which regeneration air 14 from a first regeneration air stream 16 is directed. In the depicted embodiment, the inner core 210 is the desiccant section 212, with the inner core process segment 227 being the dehumidification process segment 221 and the inner core regeneration segment 229 being the dehumidification regeneration segment 225. The inner core 210 in the depicted embodiment is the central portion of the sorption rotor 200 and can have a circular-cylindrical shape or a disk shape.
The sorption rotor 200 also includes an outer annulus 230 having an outer annulus process segment 247 through which process air 12 from a second process air stream is directed and an outer annulus regeneration segment 249 through which regeneration air 14 from a second regeneration air stream 18 is directed. In the depicted embodiment, the outer annulus 230 is the carbon-abatement section 232, with the outer annulus process segment 247 being the carbon-abatement process segment 241 and the outer annulus regeneration segment 249 being the carbon-abatement regeneration segment 245. The outer annulus 230 has an annular shape. The outer annulus 230 extends in a circumferential direction of the sorption rotor 200. The outer annulus 230 can circumscribe the inner core 210.
In the depicted embodiment and as discussed further above, the first process air stream is the same air stream as the second process air stream and the process air 12 is arranged to flow through the inner core 210 and the outer annulus 230 in series. Also as discussed above, the inner core regeneration segment 229 and the outer annulus regeneration segment 249 are arranged in parallel relative to the regeneration air 14. Accordingly, the first regeneration air stream 16 is a portion of a rotor regeneration air stream and the second regeneration air stream 18 is a portion of the rotor regeneration air stream.
The desiccant section 212 is rotatable to move the desiccant between the dehumidification process segment 221 and the dehumidification regeneration segment 225. Likewise, the carbon-abatement section 232 is rotatable to move the carbon-abatement sorbent between the carbon-abatement process segment 241 and the carbon-abatement regeneration segment 245. As depicted in FIG. 1 , the desiccant section 212 and the carbon-abatement section 232 rotate in concert. The inner core 210 and the outer annulus 230 thus can be connected to each other to rotate together and can be integrally formed with each other. Alternatively, and as discussed further below, the inner core 210 (the desiccant section 212) and the outer annulus 230 (the carbon-abatement section 232) can be independently rotatable.
Various suitable mechanisms can be used to rotate the sorption rotor 200. As shown in FIG. 1 , for example, a motor 132 is drivingly coupled to the sorption rotor 200 to transmit torque to the sorption rotor 200 and rotate the sorption rotor 200. The motor 132 can be coupled to the sorption rotor 200 by various suitable means including, for example, by a belt 134. The motor 132 rotates the belt 134, which in turn rotates the sorption rotor 200. The desiccant and the carbon-abatement sorbent are fixed within their respective sections of the sorption rotor 200 and rotate with the rotation of the sorption rotor 200. The desiccant and the carbon-abatement sorbent thus are exposed to a continuous repeating cycle of sorption and desorption to continuously condition the process air 12.
The surface vapor pressure of water of the desiccant and the surface vapor pressure of carbon compounds of the carbon-abatement sorbent in the desorption section 126 should be higher than the vapor pressure of the regeneration air 14 to regenerate the desiccant and the carbon-abatement sorbent. To increase the surface vapor pressure of carbon compounds of the desiccant, the surface vapor pressure of carbon compounds of the carbon-abatement sorbent, or both, the desiccant, the carbon-abatement sorbent, or both can be heated such as by using hot regeneration air 14. Accordingly, in some embodiments, the regeneration air 14 can be heated. Optionally, the air conditioning system 100 can include a heater 127 located within the regeneration air stream, such as within the regeneration air plenum 130, upstream of the sorption rotor 200 and, more specifically, upstream of the desorption section 126. Suitable heaters include, for example, a direct electrical heater (e.g., resistive heater), a gas-fired heater, and/or a heat-pump module.
The air conditioning system 100 also includes a process blower 118. The process blower 118 is configured to produce a process airflow of the process air 12 within the air conditioning system 100. In this embodiment, the process blower 118 is positioned upstream of the sorption rotor 200 and, more specifically, upstream of the dehumidification section 116. Similarly, the air conditioning system 100 can include a regeneration blower 128 to generate the regeneration airflow. The regeneration blower 128 can be positioned downstream of the sorption rotor 200 and, more specifically, downstream of the desorption section 126.
As noted above, the sorption rotor 200 has a plurality of segments (or zones), and, more specifically, each of the desiccant section 212 and the carbon-abatement section 232 includes a plurality of segments. The desiccant section 212 is depicted in FIG. 1 with two segments—the dehumidification process segment 221 and the dehumidification regeneration segment 225, and the carbon-abatement section 232 is depicted in FIG. 1 with two segments—the carbon-abatement process segment 241 and the carbon-abatement regeneration segment 245. Each of the desiccant section 212 and the carbon-abatement section 232 can have more than two segments. Additional segments can include, for example, a bypass segment and isolation segments.
As shown in FIG. 1 , the air conditioning system 100 includes a controller 140. In this embodiment, the controller 140 is a computing device having one or more processors 142 and one or more memories 144. The processor 142 can be any suitable processing device, including, but not limited to, a microprocessor, a microcontroller, an integrated circuit, a logic device, a programmable logic controller (PLC), an application-specific integrated circuit (ASIC), and/or a Field Programmable Gate Array (FPGA). The memory 144 can include one or more computer-readable media, including, but not limited to, non-transitory computer-readable media (non-transitory computer-readable storage media), a computer-readable non-volatile medium (e.g., a flash memory), a RAM, a ROM, hard drives, flash drives, and/or other memory devices.
The memory 144 can store information accessible by the processor 142, including computer-readable instructions that can be executed by the processor 142. The instructions can be any set of instructions or a sequence of instructions that, when executed by the processor 142, causes the processor 142 and the controller 140 to perform operations. In some embodiments, the instructions can be executed by the processor 142 to cause the processor 142 to complete any of the operations and functions for which the controller 140 is configured, as will be described further below. The instructions can be software written in any suitable programming language, or can be implemented in hardware. Additionally, and/or alternatively, the instructions can be executed in logically and/or virtually separate threads on the processor 142. The memory 144 can further store data that can be accessed by the processor 142.
The technology discussed herein makes reference to computer-based systems and actions taken by, and information sent to and from, computer-based systems. One of ordinary skill in the art will recognize that the inherent flexibility of computer-based systems allows for a great variety of possible configurations, combinations, and divisions of tasks and functionality between components and among components. For instance, processes discussed herein can be implemented using a single computing device or multiple computing devices working in combination. Databases, memories, instructions, and applications can be implemented on a single system or distributed across multiple systems. Distributed components can operate sequentially or in parallel.
In this embodiment, the controller 140 is a microprocessor-based controller that includes the processor 142 for performing various functions discussed further herein, and the memory 144 for storing various data. The various methods discussed herein can be implemented by way of a series of instructions stored in the memory 144 and executed by the processor 142. The controller 140 is configured to operate the air conditioning system 100. In particular, the controller 140 is communicatively coupled to sensors 146 within the air conditioning system 100 to receive data about the operation of the air conditioning system 100. The sensors 146 can include, for example, temperature sensors and pressure sensors variously located in the air conditioning system 100, such as in the process air plenum 110 or the regeneration air plenum 120.
The controller 140 is also operatively coupled to the various components of the air conditioning system 100 to operate the air conditioning system 100 and to discharge the regeneration air inlet 122 at desired operating conditions. For example, the controller 140 can be operatively coupled to the motor 132 (or the first motor 312 and the second motor 314 in FIG. 3 ) to rotate the sorption rotor 200 at the desired rotation speed. The controller 140 also can be operatively coupled to the process blower 118, the heater 127, the regeneration blower 128, and the like.
As noted above, in the embodiment shown in FIG. 1 , the inner core 210 and the outer annulus 230 rotate in concert with each other and can be connected to each other. For example, the inner core 210 and the outer annulus 230 can be integrally formed with each other. The sorption rotor 200 can include an outer housing 252 providing an outer structure of the rotor and into which both the inner core 210 and the outer annulus 230 can be placed and secured. For example, the outer housing 252 may be circular having a U-shaped cross section. In some embodiments, a divider 254 that extends through the thickness of the sorption rotor 200 may be positioned between the inner core 210 and the outer annulus 230. The divider 254 may be formed from an annular sheet of material that is impermeable or otherwise has a low permeability to air, such as a sheet of metal formed into an annular shape. The divider 254 may thus provide fluid isolation to prevent cross communication of the process air 12 between the desiccant section 212 and the carbon-abatement section 232 when the process air 12 flows through these sections. In some embodiments, however, the flow channels of the inner core 210 and outer annulus 230 may provide sufficient separation of the process air stream, and the divider 254 may be omitted. In some embodiments, the divider 254 may be a structural member to help support and secure the inner core 210 and the outer annulus 230 together with the outer housing 252. The outer housing 252 and the divider 254 may thus be frame members collectively forming a frame to hold the inner core 210 and the outer annulus 230. In such a case, for example, the divider 254 may be circular and have an H-shape in cross section. Separate pieces, such as two U-shaped members, can be joined together to form the divider 254.
FIG. 2 shows an arrangement of ductwork 260 of the process air plenum 110 and the regeneration air plenum 120 that may be used to form or define the rotor segments discussed above. The ductwork 260 is disposed on both sides of the sorption rotor 200 and connects the respective plenums (i.e., the process air plenum 110 and the regeneration air plenum 120) in planes parallel to the faces of the rotor.
As shown in FIG. 1 , the sorption rotor 200 includes a first face 204 and a second face 206 on the opposite side of the sorption rotor 200. In the dehumidification process segment 221, the first face 204 is an upstream face relative to the flow of the process air 12, and the second face 206 is a downstream face relative to the flow of the process air 12. In the carbon-abatement process segment 241, the first face 204 is a downstream face relative to the flow of the process air 12, and the second face 206 is an upstream face relative to the flow of the process air 12. Likewise, in the rotor regeneration segment 202, the first face 204 is a downstream face relative to the flow of the hot regeneration air 14 and the second face 206 is an upstream face relative to the flow of the hot regeneration air 14.
FIG. 2 depicts the portion of the ductwork 260 facing the first face 204 of the sorption rotor 200. In the depicted embodiment, the ductwork 260 is the same on either side of the sorption rotor 200 and the discussion of the ductwork 260 also applies to corresponding ductwork facing the second face 206. Sheet metal or other suitable material used to direct and separate air flow may be used to form the ductwork 260 depicted in FIG. 2 . The ductwork 260 can be formed from a plurality of partitions, which define the boundaries of the rotor segments. One partition of the plurality of partitions is an outer circumferential partition 262, and another partition of the plurality of partitions is an inner circumferential partition 264. The plurality of partitions also includes a plurality of radial partitions including a first radial partition 266 and a second radial partition 268.
The outer circumferential partition 262 is circular in cross section and defines the outer extent of the ductwork 260. The first radial partition 266 and the second radial partition 268 extend from the outer circumferential partition 262 to a central axis of the outer circumferential partition 262 which can also be the rotor axis 201 (FIG. 1 ). The first radial partition 266 and the second radial partition 268 separate adjacent zones or segments. In the depicted embodiment, the first radial partition 266 and the second radial partition 268 each separate the process segments (i.e., the inner core process segment 227 and the outer annulus process segment 247) from the corresponding regeneration segments (i.e., the inner core regeneration segment 229 and the outer annulus regeneration segment 249). When the rotor includes additional zones or segments, additional radial partitions may be used to define these zones.
The inner circumferential partition 264 separates the segments of the inner core 210 from the segments of the outer annulus 230, and when a divider 254 is used, the inner circumferential partition 264 may be positioned opposite the divider 254. More specifically, the inner circumferential partition 264 includes a process zone portion 264 a and a regeneration zone portion 264 b. The process zone portion 264 a of the inner circumferential partition 264 separates the flow of the process air 12 through the process air plenum 110 and separates the inner core process segment 227 from the outer annulus process segment 247. Similarly, the regeneration zone portion 264 b of the inner circumferential partition 264 separates the first regeneration air stream 16 from the second regeneration air stream 18 and separates the inner core regeneration segment 229 from the outer annulus regeneration segment 249. With the regeneration air 14 being a common flow stream through the regeneration air plenum 130, the regeneration zone portion 264 b of the inner circumferential partition 264 can be omitted.
The ductwork 260 and, more specifically, each partition of the plurality of partitions discussed above, can include one or more seals attached to the end of a corresponding partition facing the first face 204. The ductwork 260 includes a plurality of seals 270 and FIG. 2 illustrates one arrangement of the seals 270. Other seal arrangements, however, may be used. In the seal arrangement shown in FIG. 2 , each of the segments include a seal around the periphery thereof. Each seal of the plurality of seals 270 shown in FIG. 2 can be elastomeric face seals attached to the end of the partition and positioned to contact the first face 204 of the sorption rotor 200. Such face seals can have various shapes including O-shaped seals, D-shaped seals, and Ω-shaped seals. The plurality of seals 270 prevent or minimize the leakage of air, such as between adjacent segments.
For example, the outer annulus process segment 247 has a periphery and includes an outer annulus process segment seal 272. The outer annulus process segment seal 272 is one seal of the plurality of seals 270. The outer annulus process segment seal 272 shown in FIG. 2 has a portion that extends in a circumferential direction along the radially outward edge of the outer annulus process segment 247 (a radially outward circumferential portion), which in the depicted embodiment is 270 degrees. The radially outward circumferential portion is attached to the end of the outer circumferential partition 262 as depicted in FIG. 2 . The outer annulus process segment seal 272 also can have a portion that extends in a circumferential direction along the radially inward edge of the outer annulus process segment 247 (a radially inward circumferential portion), which in the depicted embodiment is 270 degrees. The radially inward circumferential portion is attached to the end of the outer circumferential partition 262. The outer annulus process segment seal 272 also includes two radial portions that connect the radially outward circumferential portion with the radially inward circumferential portion. One radial portion is attached to the end of the first radial partition 266, and the other radial portion is attached to the end of the second radial partition 268.
If the radially inward circumferential portion is omitted, the two radial portions can connect to each other. These two radial portions are located on the periphery of the inner core process segment 227 adjacent to other circumferential segments, which in the depicted embodiment is the inner core regeneration segment 229. The outer annulus regeneration segment 249 has a periphery and includes an outer annulus regeneration segment seal 274, which is another seal of the plurality of seals 270. The outer annulus regeneration segment seal 274 can also have the portions discussed above with respect to outer annulus process segment seal 272, specifically, a radially outward circumferential portion, a radially inward circumferential portion, and two radial portions arranged in a corresponding manner for the respective segments. The discussion of the outer annulus process segment seal 272 applies to these seals as well.
The inner core process segment 227 has a periphery and includes an inner core process segment seal 276, and the inner core regeneration segment 229 has a periphery and includes an inner core regeneration segment seal 278. Each of the inner core process segment seal 276 and the inner core regeneration segment seal 278 is one seal of the plurality of seals 270. Each of these seals can also have the portions discussed above with respect to outer annulus process segment seal 272, specifically, a radially outward circumferential portion and two radial portions arranged in a corresponding manner for the respective segments. The discussion of the outer annulus process segment seal 272 applies to these seals as well. In the depicted embodiment, the radially inward circumferential portion is omitted and the two radial portions connect to each other. In other embodiments, such as discussed further below with respect to FIG. 3 , a radially inward circumferential portion maybe used to provide a seal with the shaft 320 (FIG. 3 ).
The plurality of seals 270 discussed herein are arranged in a cascading seal arrangement. The cascading seal arrangement includes two seals (or portions thereof) that are arranged next to each other and collectively form a single sealing boundary between adjacent segments of the sorption rotor 200. For example, the inner core process segment 227 is separated from the outer annulus process segment 247 by both the inner core process segment seal 276 and the outer annulus process segment seal 272. More specifically, the radially outward circumferential portion of the inner core process segment seal 276 and the radially inward circumferential portion of the outer annulus process segment seal 272 collectively form the seal between the inner core process segment 227 and the outer annulus process segment 247. These two portions of the inner core process segment seal 276 and the outer annulus process segment seal 272 thus form a cascading seal between the inner core process segment 227 and the outer annulus process segment 247. These adjacent and overlapping seals create continuous sealing interface that enhances the effectiveness of the sealing system for the sorption rotor 200 discussed herein.
Although face seals are depicted and described above, other seals may be used. For example, the seals between the outer circumferential partition 262 and the inner circumferential partition 264 may be formed between the outer housing 252 and the inner circumferential partition 264, respectively and other circumferential seal designs may be used. In another example, shaft seals may be used, when the sorption rotor 200 or a portion thereof is rotated by a shaft 320 (FIG. 3 ).
FIG. 3 is a schematic of another sorption rotor 300 that can be used in place of the sorption rotor 200 in the air conditioning system 100 of FIG. 1 . The sorption rotor 300 shown in FIG. 3 is similar to the sorption rotor 200 discussed above. The same reference numerals will be used for the same or similar components and the discussion of those components applies here. In FIG. 1 , the inner core 210 and the outer annulus 230 are connected and rotated together by the motor 132. In FIG. 3 , however, the inner core 210 and the outer annulus 230 are rotated independently. For example, a first motor 312 can drive the outer annulus 230 using the belt 134 in the manner discussed above. The sorption rotor 300 includes a shaft 320 (e.g., a central shaft) attached to the inner core 210. A second motor 314 is drivingly connected to the shaft 320 to rotate the inner core 210 independently from the outer annulus 230. Driving the inner core 210 separately or independently from the outer annulus 230 allows the inner core 210 and the outer annulus 230 to be rotated at different speeds or to be rotated in different directions. The controller 140 can be configured to be operable to rotate the inner core 210 at a first speed and the outer annulus 230 at a second speed, with the first speed being different than the second speed. Although described with reference to two separate motors (i.e., the first motor 312 and the second motor 314), other arrangements can be used. For example, a single motor can be used with a gear train connecting each of the belt 134 and the shaft 320. The gear train can be arranged and configured to drive the belt 134 and the shaft 320 at different rotational speeds.
The sorbent of each of the inner core 210 and the outer annulus 230 can be housed within their own housing. Separate sets of bearings can then be used to independently support the rotation of the inner core 210 and the rotation of the outer annulus 230. For example, a gap may be maintained between the inner core 210 and the outer annulus 230 to allow for independent rotation. The outer annulus 230 can be supported by rollers around the periphery of the outer annulus 230, and the inner core 210 can be supported by bearings for the shaft 320.
FIG. 4 is a schematic of yet another sorption rotor 302 that can be used in place of the sorption rotor 200 in the air conditioning system 100 of FIG. 1 . The sorption rotor 302 shown in FIG. 4 is similar to the sorption rotor 200 discussed above. The same reference numerals will be used for the same or similar components and the discussion of those components applies here. Likewise, the features discussed in this embodiment may be applied to the sorption rotor 300 shown in FIG. 3 .
The inner core 210 has an axial length of the sorbent in the axial direction (an inner core thickness t_c), and the outer annulus 230 has an axial length of the sorbent in the axial direction (an outer annulus thickness t_a). In FIG. 1 , the inner core 210 and the outer annulus 230 are shown as having the same thickness, that is, having the same axial length. To increase the surface area of one of the sorbents, such as the desiccant or the carbon-abatement sorbent, the axial length may be increased. The inner core thickness t_cand the outer annulus thickness t_athus can be different, and the axial length of one of the inner core 210 and the outer annulus 230 is longer than the axial length of the other one of the inner core 210 and the outer annulus 230. As shown in FIG. 4 , for example, the inner core thickness t_cis larger (the axial length is longer) than the outer annulus thickness t_a, but the opposite arrangement can also be used.
The sorption rotors 200, 300, 302 discussed herein are not limited to structures defining a flow channel therethrough but includes other rotary sorbent systems where the sorbent can have other arrangements. For example, the sorbent can also be formed as granules or particulates and form a porous mass through which air can flow. Such granular desiccant can be formed in a rotary bed that is arranged horizontally.
The sorption rotors 200, 300, 302 can be used in the air conditioning system 100 to condition a process air 12 using two or more sorbents, but with a single rotor, allowing at least the size of the air conditioning system 100 to be reduced. In some embodiments, the sorbents can be different to target different molecules within the process air 12. For example, one sorbent can be a hydrophilic sorbent, such as a desiccant, and the other sorbent can be a hydrophobic sorbent, such as a carbon-abatement sorbent. Two of the sorbents can be arranged with one radially outward of the other, such as with an inner core 210 and an outer annulus 230. These two sorbents can be rotated together and in concert with each other. Alternatively, these sorbents can be arranged and operated differently within the rotor to have desired performance characteristics. For example, the sorbents can be rotated independently of each other at different speeds, or the sorbents can be arranged with different axial lengths.
Although certain features are described with respect to one of the embodiments above, those features may be used either independently from other features described in that embodiment or combined with features described in other embodiments.
Although this invention has been described with respect to certain specific exemplary embodiments, many additional modifications and variations will be apparent to those skilled in the art in light of this disclosure. It is, therefore, to be understood that this invention may be practiced otherwise than as specifically described. Thus, the exemplary embodiments of the invention should be considered in all respects to be illustrative and not restrictive, and the scope of the invention to be determined by any claims supportable by this application and the equivalents thereof, rather than by the foregoing description.

Claims

What is claimed is:

1. An air conditioning system for conditioning process air of a process air stream, the air conditioning system comprising:

a rotor including:

a hydrophilic section including a hydrophilic sorbent, the hydrophilic section having a hydrophilic process segment through which the process air stream is directed; and

a hydrophobic section including a hydrophobic sorbent, the hydrophobic section having a hydrophobic process segment through which the process air stream is directed,

wherein the process air of the process air stream flows though the hydrophilic process segment in series with the hydrophobic process segment, the process air flowing through the hydrophilic process segment before the hydrophobic process segment.

2. The air conditioning system of claim 1, wherein the rotor includes an axis, with the axis defining an axial direction,

wherein the process air stream is directed through the hydrophilic process segment in a hydrophilic process flow direction that is parallel to the axial direction, and

wherein the process air stream is directed through the hydrophobic process segment in a hydrophobic process flow direction, the hydrophobic process flow direction being parallel to the axial direction and opposite to the hydrophilic process flow direction.

3. The air conditioning system of claim 1, wherein one of the hydrophilic section or the hydrophobic section is positioned radially outward of the other one of the hydrophilic section or the hydrophobic section.

4. The air conditioning system of claim 1, wherein one of the hydrophilic section or the hydrophobic section circumscribes the other one of the hydrophilic section or the hydrophobic section.

5. The air conditioning system of claim 1, wherein the rotor includes an inner core containing a sorbent and an outer annulus containing a sorbent, the outer annulus being arranged radially outward of the inner core, the hydrophilic section being one of the inner core or the outer annulus and the hydrophobic section being the other one of the inner core or the outer annulus.

6. The air conditioning system of claim 5, wherein the hydrophilic section is the inner core and the hydrophobic section is the outer annulus.

7. The air conditioning system of claim 1, wherein the rotor includes a regeneration segment through which regeneration air in a regeneration air stream is directed, and

wherein the hydrophilic section is rotatable to move the hydrophilic sorbent between the hydrophilic process segment and the regeneration segment and the hydrophobic section is rotatable to move the hydrophobic sorbent between the hydrophobic process segment and the regeneration segment.

8. The air conditioning system of claim 7, wherein the hydrophilic section and the hydrophobic section rotate in concert.

9. The air conditioning system of claim 7, wherein the hydrophilic section and the hydrophobic section are independently rotatable.

10. The air conditioning system of claim 7, wherein the hydrophilic section and the hydrophobic section are independently rotatable to rotate at different speeds.

11. The air conditioning system of claim 7, further comprising a heater positioned upstream of the regeneration segment of the rotor to heat the regeneration air stream.

12. An air conditioning system comprising:

a rotor including:

an inner core having an inner core process segment through which process air from a first process air stream is directed and an inner core regeneration segment through which regeneration air from a first regeneration air stream is directed, the inner core containing a sorbent that is rotatable between the inner core process segment and the inner core regeneration segment; and

an outer annulus having an outer annulus process segment through which process air from a second process air stream is directed and an outer annulus regeneration segment through which regeneration air from a second regeneration air stream is directed, the outer annulus containing a sorbent that is rotatable between the outer annulus process segment and the outer annulus regeneration segment, the outer annulus being arranged radially outward of the inner core and being rotatable independently from inner core.

13. The air conditioning system of claim 12, wherein the inner core and the outer annulus are independently rotatable to rotate at different speeds.

14. The air conditioning system of claim 12, further comprising ductwork including a partition separating the inner core process segment from the outer annulus process segment.

15. The air conditioning system of claim 14, wherein the partition includes a seal formed between the partition and a face of the rotor.

16. The air conditioning system of claim 12, wherein the inner core regeneration segment and the outer annulus regeneration segment collectively form a rotor regeneration segment through which regeneration air from a rotor regeneration air stream is directed, and

wherein the first regeneration air stream is a portion of the rotor regeneration air stream and the second regeneration air stream is another portion of the rotor regeneration air stream.

17. The air conditioning system of claim 16, further comprising a heater positioned upstream of the rotor regeneration segment of the rotor to heat the rotor regeneration air stream.

18. The air conditioning system of claim 12, wherein the first process air stream is the same air stream as the second process air stream and the process air is arranged to flow through the inner core and the outer annulus in series.

19. The air conditioning system of claim 18, wherein the sorbent of the inner core is a different sorbent than the sorbent of the outer annulus.

20. The air conditioning system of claim 19, wherein the sorbent of one of the inner core or the outer annulus is a hydrophilic sorbent, and the sorbent of the other one of the inner core or the outer annulus is a hydrophobic sorbent.