DESICCANT AIR CONDITIONING SYSTEM USING REFRIGERANT

A liquid desiccant air conditioning system (LDAC). The LDAC has a plurality of modules including at least an initial module and a terminal module that may include one or more intermediate modules. The liquid desiccant is passed through each module and contacts an airstream in each module and subsequently collected in a basin. The liquid desiccant is supplied to a common heat exchanger where thermal energy is exchanged between the liquid desiccant and a refrigerant. The liquid desiccant is supplied from the common heat exchanger to a desiccant distributor for each of the plurality of modules such that the concentration and temperature of the liquid desiccant is essentially the same at each desiccant distributor.

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Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

The present application claims the benefit of U.S. Provisional patent application Ser. No. 63/578,306, titled Desiccant Air Conditioning System Using Refrigerant, filed Aug. 23, 2023, the disclosure of which is incorporated herein as if set out in full and for all purposes.

The present application is related to U.S. Pat. No. 9,982,901, titled Air Conditioning Method using a Staged Process using a Liquid Desiccant, which issued May 29, 2018, and U.S. Pat. No. 10,823,436, titled the same, which issued Nov. 3, 2020, the disclosures of with are incorporated herein by reference as if set out in full for all purposes.

BACKGROUND

The technology of the present application relates to air conditioning systems and methods that can cool and de-humidify air.

Desiccant interacting with an air stream can cool and de-humidify air as explained in both U.S. Pat. Nos. 9,982,901 and 10,823,436. As explained in these patents, desiccant based systems have been known for a long time. Prior to these patents, however, desiccant based systems were not cost effective as the energy savings of the desiccant based systems were not sufficient to overcome the high capital investment.

U.S. Pat. Nos. 9,982,901 and 10,823,436 describe a desiccant air conditioning system that has a device 1 that cools and de-humidifies an air stream using desiccant. The desiccant is diluted in stages in the device 1. A device 2 is provided that is a desiccant regenerator. The diluted desiccant is concentrated in the device 2 and eventually recirculated back to device 1.

Although an improvement over existing desiccant air conditioning systems, the systems described in U.S. Pat. Nos. 9,982,901 and 10,823,436 require a number of parts and complex piping arrangement for the various fluids that can be costly and relatively complex. In addition, if liquid water or liquid water/glycol solutions are used as the cooling and/or heating fluid as referenced U.S. Pat. No. 9,982,901, this can often require additional complexity in terms of piping, circulating pumps, external tanks, and in some cases external energy source such as a water source or geothermal heat pump, combined heat and power (CHP) system, or external chillers and boilers.

Thus, against this background, it would be desirable to provide an improved desiccant air conditioning system with less costly piping and parts.

SUMMARY

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary, and the foregoing Background, is not intended to identify key aspects or essential aspects of the claimed subject matter. Moreover, this Summary is not intended for use as an aid in determining the scope of the claimed subject matter.

In some aspects of the technology, a liquid desiccant air conditioning system (LDAC) using a refrigerant is provided. The LDAC comprises at least an initial module, comprising at least a housing with a media pad and a desiccant distributor configured to disburse liquid desiccant from the desiccant distributor to the media pad; and a terminal module in fluid communication with the initial module, the terminal module comprising at least a housing with a media pad and a desiccant distributor configured to disburse liquid desiccant from the desiccant distributor to the media pad. The LDAC further has at least a first basin in fluid communication with at least one of the initial module or the terminal module to receive liquid desiccant from the media pad (or pads). An air intake is in fluid communication with the initial module to receive untreated air and direct the untreated air to the initial module and an air exhaust in fluid communication with the terminal module to exhaust treated air from the LDAC. A common heat exchanger in fluid communication with at least the first basin and each of the desiccant distributors, wherein the common heat exchanger is in fluid communication with a refrigerant that is operationally coupled to the liquid desiccant to exchange thermal energy between the refrigerant and the liquid desiccant.

In some embodiments, a method of using liquid desiccant to condition an air stream is provided. The method includes moving an air stream through a liquid desiccant air conditioning system (LDAC) from an air intake through at least an initial module and a terminal module to an air exhaust such that the air stream contacts a media pad in each of the initial module and terminal module. As the air stream contacts the media pad, the technology causes a liquid desiccant to flow from a desiccant distributor through the media pad in each of the initial module and terminal module wherein the liquid desiccant contacts the air stream and is collected in a basin. The liquid desiccant is pumped from the basin to a liquid desiccant input of a common heat exchanger where thermal energy between the liquid desiccant and a refrigerant in the common heat exchanger is exchanged. Finally, the liquid desiccant is supplied to the common heat exchanger to the desiccant distributor of each of the initial module and the terminal module.

These and other aspects of the present system and method will be apparent after consideration of the Detailed Description and Figures herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present invention, including the preferred embodiment, are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.

FIG. 1 shows a liquid desiccant air conditioning device consistent with the technology of the present application

FIG. 2 shows a liquid desiccant air conditioning device consistent with the technology of the present application.

FIG. 3 shows a liquid desiccant air system consistent with the technology of the present application in more detail.

 DETAILED DESCRIPTION

The technology of the present application will now be described more fully below with reference to the accompanying figures, which form a part hereof and show, by way of illustration, specific exemplary embodiments. These embodiments are disclosed in sufficient detail to enable those skilled in the art to practice the technology of the present application. However, embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. The following detailed description is, therefore, not to be taken in a limiting sense.

The technology of the present application is described with specific reference to a liquid desiccant air conditioning system. However, the technology described herein may be used with applications other than those specifically described herein. For example, the technology of the present application may be applicable to other liquid desiccant de-humidifying systems, liquid desiccant regeneration systems, other evaporative systems or the like. Moreover, the technology of the present application will be described with relation to exemplary embodiments. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. Additionally, unless specifically identified otherwise, all embodiments described herein should be considered exemplary.

With reference now to FIG. 1, a liquid desiccant air conditioning system 1 (LDAC 1) is shown. The features of LDAC 1 are described in U.S. Pat. Nos. 9,982,901 and 10,923,436, which patents are incorporated by reference as if set out in full. For completeness, however, the LDA I will be described herein in part for an understanding of the present technology. LDAC 1 receives an incoming air stream 3 to be cooled and de-humidified. The LDAC 1 comprises a modular structure having at least an initial module 54 and a terminal module 56. The initial module 54 and the terminal module 56 may be referred to as first module 54 and last module 56, first module 54 and second module 56, etc. However, the designation of first and/or second are to distinguish different modules and not necessarily related to a particular order. LDAC 1 optionally includes one or more intermediate module 55, which may be referred to herein as third module 55, fourth module 55, etc. The modules 54, 55, and 56 are essentially identical and interchangeable. The modules 54, 55, and 56 include an air enclosure 20 (or housing 20) containing a media pad 21, a desiccant distributor 23, and a basin 30 (although the basin 30 may be external to the housing 20 in certain embodiments).

Still with reference to FIG. 1, the LDAC 1 operates by moving air, via air stream 3, through the media pads 21 of the modules, such as modules 54 (initial module) and module 56 (terminal module), while liquid desiccant is dispersed by the desiccant distributor 23 through the media pad 21 to the basin 30. The liquid desiccant contacts the air and removes moisture from the air, i.e., de-humidifies the air, and cools the air in air stream 3. The air stream 3 is moved by an air movement device 34, such as a fan 34 as shown until the air stream 3 is exhausted out of an outlet 39. Alternatively, the air movement device 34 may be located at an intake 25 or inlet 25. The exhaust 39 or outlet 39 may, optionally, include one or more demisters 26 to remove water or other liquid in the air stream 3 at the exhaust.

The inlet 25 may, optionally, comprise a coil 36. As shown, the coil 36 is used to precondition the air stream 3 in advance of the air stream 3 entering the initial module 54. In this case, the coil 36 is used to cool (or heat) the air stream.

Generally, the liquid desiccant flows both cross and counter current to the air stream. The air stream enters the LDAC 1 with a relatively higher humidity and, as it travels through the modules in a generally left to right direction, as shown, is contacted by liquid desiccant to reduce the humidity until it exits the LDAC 1 at a relatively lower humidity. Simultaneously, the liquid desiccant flows, in each module through the media pads 21 from the desiccant distributor 23 to the sump 30 in a cross current (vertically from the top to the bottom as shown) and essentially orthogonal to the air stream 3, although other angulation is possible. Also, the liquid desiccant traverses from the terminal module 56 forward to the initial module 54 (generally right to left as shown), which is counter current to the air stream. As the liquid desiccant travels in a counter current, the liquid desiccant moves from a relatively higher concentration of liquid desiccant to a relatively lower concentration of liquid desiccant, as explained in U.S. Pat. Nos. 9,982,901 and 10,923,436. For example, the liquid desiccant may move from module 56 towards module 54 via a pump, such as pump 24, a tubular connection between basins 30, such as tube 27. Each basin 30 also may include level device 28, such as a float device or the like, to maintain the liquid desiccant level in each basin 30.

As shown in FIG. 1, each module (54, 55, 56) of LDAC 1 includes a heat exchanger 22, shown as external to the housing 20 although it could be contained in the housing 20 in certain embodiments. The heat exchanger 22 receives liquid desiccant from the basin 30 and cools (or heats) the liquid desiccant prior the liquid desiccant being distributed by desiccant distributor 23. The cooling (or heating in the alternative) of the liquid desiccant in heat exchanger 22 occurs when cooling (or heating) fluid 5 exits an external exchanger 51 and is introduced to heat exchanger 22, where each heat exchanger 22 is in parallel such that the temperature of the cooling (or heating) fluid 5 is substantially the same at the input to each of the heat exchangers 22, in other words, the temperature of the fluid 5 arrives at each module 54, 55, 56 at essentially the same temperature. The fluid leaves the external exchanger via fluid stream 5 enters the heat exchanger 22 and removes heat from (or adds heat to) the liquid desiccant prior to the liquid desiccant being discharged by the desiccant distributor 23. The cooling (or heating) fluid leaves the heat exchanger and returns the external exchanger 51 via fluid stream 6.

The fluids are supplied in parallel to each heat exchanger 22 in each module (54, 55, 56) such that the fluid is at essentially the same temperature at the heat exchanger 22 input to maximize the heat transfer out of the desiccant and thus from the treated air. It has been demonstrated that this maximizes the enthalpy change in each sector and enables a lower source temperature to be used than if the cooling fluid is supplied in series to each heat exchanger. For a regenerative configuration, a similar argument applies to the effectiveness of using a common heating source for each sector in the desiccant regenerator.

As can be appreciated, the heat exchanger 22 for each module (54, 55, 56) requires a significant number of repetitive parts. Additionally, the use of the plurality of heat exchangers 22 and the external exchanger 51 introduces an intermediate cooling fluid (shown by flows 5 and 6), between the liquid desiccant and the water of the external exchanger 51, which in this embodiment is a chiller, or any other chilled water source. The components and the like introduce complexity and disadvantages to the LDAC 1, such as, for example, additional cost and additional piping connections that must be properly sealed to name but two.

With reference to FIG. 2, an alternative LDAC 2 is shown. LDAC 2 is substantially the same as LDAC 1 in many aspects including, for example, the modules 54, 55, and 56 along with the components included therein as shown in FIG. 1, such as, a media pad 21 and a desiccant distributor 23 for each module (not shown in FIG. 2 for clarity and convenience but shown in FIG. 1). The basins 30 also have a desiccant pump 24 coupled to the basin. As shown, each module 54, 55, 56 of LDAC 2 has a basin 30 and a desiccant pump 24 to move the liquid desiccant from one basin to the next basin or into a common return header 60 (shown in phantom) as explained further below. Except as required for an understanding of the present technology, these common components are not redescribed with reference to LDAC 2 for simplicity.

FIG. 2 shows LDAC 2 with an initial module 54 and a terminal module 56 with two intermediate modules 55, although LDAC 2 can have no intermediate modules 55 or almost any number of intermediate modules 55. Each module includes a basin 30 and pump 24 as shown. As explained with respect to LDAC 1, the liquid desiccant is pumped from each basin to an individual heat exchanger 22 associated with each module and that an external exchanger 51 is used to cool (or heat) the desiccant. LDAC 2 removes the individual heat exchanger 22 and runs the liquid desiccant from the basin(s) to a common desiccant heat exchanger 4, which is shown as receiving a liquid desiccant, or brine solution. Such systems can use a variety of liquid desiccant solutions, each having unique properties. In some instances, each of the pumps 24 are coupled to a common return header 60 that is coupled to the common desiccant heat exchanger 4. In still other embodiments, the basins 30 are replaced by the common return header 60 (which may be considered a common basin 60) and the pumps 24 are replaced by a single pump 24. The common desiccant heat exchanger 4 uses a refrigerant to remove heat to cool (or add heat to heat) the liquid desiccant.

While not shown, the common heat exchanger 4 may be, for example, part of a compressor refrigerant system. The common heat exchanger 4 receives liquid refrigerant at a refrigerant input 412 of the common heat exchanger 4. The liquid refrigerant vaporizes as it passes through the common heat exchanger 4 and removes heat from the liquid desiccant. The vaporized (and any remaining liquid) refrigerant discharges from a refrigerant output 410 of the common heat exchanger 4 and is compressed back to a liquid.

Similarly, a liquid desiccant solution, or LD, which can be any of a number of liquid desiccants, enters the common heat exchanger 4 at a liquid desiccant input 412. The relatively hot liquid desiccant may be provided to the liquid desiccant input 412 via a common return header 60, shown in phantom on FIG. 2 as an optional return. If the common return header 60 is used, each module basin 30 may be combined into a single common basin (not shown) and a single pump 24 may be provided. Alternatively, as shown, each module 54, 55, 55, and 56 includes a basin 30 and a pump 24. The pump 24 of the initial module 54 pumps desiccant from basin 30 of module 54 to basin 30 of module 55 and each subsequent module 55 has liquid desiccant pumped from its basin 30 to the next module 55 until the terminal module 56. In other words, each basin 30 is in fluid communication with the next basin 30. Finally, the pump 24 of terminal module 56 pumps the liquid desiccant to the liquid desiccant input 412 of the common heat exchanger 4.

Liquid desiccant moves through common heat exchanger 4. Heat is removed from the liquid desiccant until it is relatively cooler than when it entered the common heat exchanger 4. The liquid desiccant exits to a common supply header 62 and distributed to the media pads of LDAC 2. A three-way valve 414 downstream of the liquid desiccant output 410 may direct all or a portion of the liquid desiccant from liquid desiccant output 410 to the LDAC 2, via the common supply header 62, or all or a portion of the liquid desiccant from the liquid desiccant output 410 to the basin 30. The common supply header 62 is in fluid communication with the common heat exchanger 4 via a liquid desiccant output 412. The common supply header 62 is in fluid communication with the plurality of desiccant distributors 23, as shown in FIG. 1.

The liquid desiccant in the common supply header 62 provides liquid desiccant at a consistent temperature to each of the modules associated with LDAC 2, which as shown includes modules 54, 55, 55, and 56. The liquid desiccant is distributed through the media pads 21 of the modules and collects in the basin 30 (or a common basin 30 or common return header/basin 60). The liquid desiccant in each media pad 21 should be diluted differently as it travels through the separate media pads 21 as the air stream 3 traveling through the media pad will have diminishing humidity as the liquid desiccant of upstream pads removes moisture.

FIG. 2 shows a schematic of the technology of the present application. FIG. 3 shows another liquid desiccant air conditioning system including both the dehumidification/refrigerator portion 302 and the regeneration/concentrator portion 304 of an LDAC 300 consistent with the technology of the present application. The LDAC 300 includes piping, exchangers, compressors, similar to the above, which will be further described in connection with operation of LDAC 300. For clarity, FIG. 3 is a top-down view of the LDAC 300, but similar systems can provide different orientations and locations of the various components, depending upon application.

The LDAC 300 includes a refrigerant-based condenser/evaporator 301, not specifically shown or described herein. The LDAC 300 receives a cold refrigerant 306 from the condenser/evaporator 301. The cold refrigerant 306 is received as a cooling fluid at a cold common heat exchanger 308, referred to as a liquid desiccant heat exchanger 308 in the description of FIG. 3. The refrigerant 306, after cooling the liquid desiccant, is returned to the condenser/evaporator 301.

The cold, liquid desiccant 310 is discharged from the common heat exchanger 308, a/k/a, the liquid desiccant heat exchanger 308 to the dehumidification/refrigerator portion 302 and supplied to the desiccant distributor, not shown in FIG. 3 but described and shown above. Also, as described above, a three-way valve may be used to direct all or a portion of the cold, liquid desiccant 310 to the desiccant distributor for distribution to the media pads or to a holding tank 314, below. In some embodiments, the liquid desiccant is chilled to about 20 or 30° F. below the desired dry bulb temperature but other temperatures are possible and this is but an example. The cold, liquid desiccant 310 is supplied by parallel piping 312 to the distributors and flows onto the media pads of each of the modules (of which four (4) modules are shown), or a combination of flows split between the distributors and the basin (30) as indicated in FIG. 2. In some embodiments, the liquid desiccant supplied by the parallel piping 312 is the same temperature and same concentration as it is distributed into the media pads. Of course, the concentration will change for each module as the liquid desiccant flows through the media pad to the basin, sump, or holding tank 314.

The outside air 316 is moved through the refrigerant portion 302 of the LDAC 300. As the outside air moved through the refrigerant portion 302, it contacts the wetted media and moisture is removed from the air and absorbed by the liquid desiccant causing an exothermic reaction. The reaction both dilutes and heats the desiccant as it moves to the holding tank 314.

The diluted liquid desiccant 318 is pumped to an energy-economizing brine heat exchanger 320, which is in the concentrator portion 304 of LDAC 300 as will become apparent below. While the brine heat exchanger 320 is shown in the concentrator portion 304, it could be located elsewhere. Also, other parts of LDAC 300 may be arranged in different locations. The brine heat exchanger 320 also receives concentrated liquid desiccant 322, as will become apparent below. The concentrated liquid desiccant 322 transfers heat to the diluted liquid desiccant 318 to cool the concentrated liquid desiccant 322 and heat the diluted liquid desiccant 318.

The heated, diluted liquid desiccant 324 exits the brine heat exchanger 320 and is provided to the basin or holding tank of the concentrator/regenerator portion 304 to regain its prior concentration. Liquid desiccant from the basin of the concentrator/regenerator portion 304 is pumped to hot common heat exchanger 309. The condenser/evaporator 301 provides a hot fluid 307, typically a gas, to further heat the heated, diluted liquid desiccant 324 at a hot common heat exchanger 309 and output a hot, diluted desiccant 326. For reference, the application uses terms like hot, warm, cool, cold, as terms of relativity. For example, the heated, diluted liquid desiccant 324 is heated to hot, diluted liquid desiccant 326. One of ordinary skill in the art would understand now, on reading the present application, that the hot, diluted liquid desiccant 326 simply means the liquid desiccant 326 has a relatively higher temperature than the heated, diluted liquid desiccant 324, etc.

The hot, diluted desiccant 326 flows to the concentrator portion 304 of LDAC 300 and supplied to the desiccant distributor, not shown in FIG. 3 but described and shown above. In some embodiments. Also, as described above, a three-way valve may be used to direct all or a portion of the hot, diluted desiccant 326 to the desiccant distributor for distribution to the media pads or to a holding tank/basin of the concentrator portion 304. The hot, diluted desiccant 326 is supplied by parallel piping 328 to the distributors and flows onto the media pads of each of the modules (of which four (4) modules are shown), or is split between flow to the desiccant distributors 23 (FIG. 1) and to the basin 30 as shown in FIG. 2. Unlike the LDAC in some embodiments, the liquid desiccant supplied by the parallel piping 312 is the same temperature and same concentration as it is distributed into the media pads. Of course, the concentration will change for each module as the liquid desiccant flows through the media pad to the basin, sump, or holding tank 330.

Outside air 332 is moved through the media pads. The concentrator portion 304 is configured such that the outside air 332 is warmed and humidified by the hot, diluted liquid desiccant 326, which involves a transfer of heat and moisture from the liquid desiccant to the outside air flowing through the media pads. The basin, sump, or holding tank 330 receives the concentrated liquid desiccant 322, which is provided to the economizing brine heat exchanger 320, described above, to be cooled as it heats the diluted liquid desiccant 318. The brine heat exchanger 320 outputs a cool, concentrated liquid desiccant 334 to the condenser/evaporator 301 where a fluid, typically liquid refrigerant, further cools the cool, concentrated liquid desiccant 334 such that the cold, liquid desiccant 310 is discharged from the liquid desiccant heat exchanger 308, or common heat exchanger 308, to the dehumidification/refrigerator portion 302 of LDAC 300, whereby the cycle is repeated.

The technology has been described in language that is specific to certain structures and materials, it is to be understood that the invention defined in the appended claims is not necessarily limited to the specific structures and materials described. Rather, the specific aspects are described as forms of implementing the claimed invention. Because many embodiments of the invention can be practiced without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. Unless otherwise indicated, all numbers or expressions, such as those expressing dimensions, physical characteristics, etc. used in the specification (other than the claims) are understood as modified in all instances by the term “approximately.” At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the claims, each numerical parameter recited in the specification or claims which is modified by the term “approximately” should at least be construed in light of the number of recited significant digits and by applying ordinary rounding techniques. Moreover, all ranges disclosed herein are to be understood to encompass and provide support for claims that recite any and all subranges or any and all individual values subsumed therein. For example, a stated range of 1 to 10 should be considered to include and provide support for claims that recite any and all subranges or individual values that are between and/or inclusive of the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more and ending with a maximum value of 10 or less (e.g., 5.5 to 10, 2.34 to 3.56, and so forth) or any values from 1 to 10 (e.g., 3, 5.8, 9.9994, and so forth).

Claims

1. A liquid desiccant air conditioning system (LDAC) comprising,

an initial module, comprising at least a housing with a media pad and a desiccant distributor configured to disburse liquid desiccant from the desiccant distributor to the media pad;
a terminal module in fluid communication with the initial module, the terminal module comprising at least a housing with a media pad and a desiccant distributor configured to disburse liquid desiccant from the desiccant distributor to the media pad;
at least a first basin in fluid communication with at least one of the initial module or the terminal module to receive liquid desiccant from the media pad;
an air intake in fluid communication with the initial module to receive untreated air and direct the untreated air to the initial module;
an air exhaust in fluid communication with the terminal module to exhaust treated air from the LDAC;
a common heat exchanger in fluid communication with at least the first basin and each of the desiccant distributors, wherein the common heat exchanger is in fluid communication with a refrigerant that is operationally coupled to the liquid desiccant to exchange thermal energy between the refrigerant and the liquid desiccant.

2. The LDAC of claim 1 comprising at least one liquid desiccant pump in fluid communication with at least the first basin and a liquid desiccant input of the common heat exchanger.

3. The LDAC of claim 1, wherein the first basin is a common return header for at least the initial module and the terminal module.

4. The LDAC of claim 1 comprising at least one intermediate module comprising at least a housing with a media pad and a desiccant distributor configured to disburse liquid desiccant from the desiccant distributor to the media pad.

5. The LDAC of claim 4, wherein the at least one intermediate module includes a media pad that is in fluid communication with the common return header.

6. The LDAC of claim 1 comprising at least a second basin, wherein the first basin is associated with the initial module and the second basin is associated with the terminal module wherein the first and second basin are in fluid communication with the common heat exchanger.

7. The LDAC of claim 6 wherein the first basin and second basin are in fluid communication such that the first basin is downstream of the second basin and the second basin is upstream of the first basin and downstream of the common heat exchanger.

8. The LDAC of claim 1 comprising a common supply header in fluid communication with a liquid desiccant output of the common heat exchanger and each desiccant distributor.

9. The LDAC of claim 8, comprising a three way valve in fluid communication with the common heat exchanger and each desiccant distributor and at least the first basin to distribute liquid desiccant from the common heat exchanger to each desiccant distributor and the first basin.

10. A method of using liquid desiccant to condition an air stream, comprising:

moving an air stream through a liquid desiccant air conditioning system (LDAC) from an air intake through at least an initial module and a terminal module to an air exhaust such that the air stream contacts a media pad in each of the initial module and terminal module;
causing a liquid desiccant to flow from a desiccant distributor through the media pad in each of the initial module and terminal module wherein the liquid desiccant contacts the air stream;
collecting the liquid desiccant in a basin;
pumping the liquid desiccant from the basin to a liquid desiccant input of a common heat exchanger;
exchanging thermal energy between the liquid desiccant and a refrigerant in the common heat exchanger; and
supplying liquid desiccant from the liquid desiccant output of the common heat exchanger to the desiccant distributor of each of the initial module and the terminal module.

11. The method of claim 10 wherein the liquid desiccant from the common heat exchanger is substantially the same temperature and concentration at the desiccant distributor for both the initial module and the terminal module.

12. The method of claim 10 wherein collecting the liquid desiccant in the basin comprises using a common return header to the common heat exchanger.

13. The method of claim 10 wherein exchanging thermal energy comprises using a compressor refrigerant system.

14. The method of claim 10 comprising moving the air stream through at least one intermediate module, causing liquid desiccant to flow from a desiccant distributor through the media pad of the at least one intermediate module, and supplying liquid desiccant from the output of the common heat exchanger to the desiccant distributor of the at least one intermediate module.

15. The method of claim 10 wherein supplying liquid desiccant from the common heat exchanger comprises supplying a portion of the liquid desiccant to the desiccant distributor or each of the initial module, the at least one intermediate module, and the terminal module and a portion of the liquid desiccant to the first basin.

16. A liquid desiccant air conditioning system (LDAC) comprising,

a refrigerator portion, the refrigeration portion comprising: an initial module, comprising at least a housing with a media pad; a terminal module in fluid communication with the initial module, the terminal module comprising at least a housing with a media pad; a desiccant distributor configured to disburse liquid desiccant from the desiccant distributor to the media pad of the initial module and the terminal module; and a basin in fluid communication with at least one of the initial module or the terminal module to receive liquid desiccant from the media pad;
a concentrator portion, the concentrator portion comprising: an initial module, comprising at least a housing with a media pad; a terminal module in fluid communication with the initial module, the terminal module comprising at least a housing with a media pad; a desiccant distributor configured to disburse liquid desiccant from the desiccant distributor to the media pad of the initial module and the terminal module; and a basin in fluid communication with at least one of the initial module or the terminal module to receive liquid desiccant from the media pad;
a condenser/evaporator heat exchanger in fluid communication with the refrigerator portion and the concentrator portion, the common condenser/evaporator heat exchanger comprising: a cold common heat exchanger in fluid communication with the basin of the concentrator to receive concentrated liquid desiccant and output cold liquid desiccant to the refrigerator portion; a hot common heat exchanger in fluid communication with the basin of the refrigerator portion to receive diluted liquid desiccant and output hot liquid desiccant to the concentrator portion;
an air intake in fluid communication with the initial module to receive untreated air and direct the untreated air to the initial module; and
an air exhaust in fluid communication with the terminal module to exhaust treated air from the LDAC.

17. The LDAC of claim 16 comprising a three way valve in fluid communication with the output of the cold common heat exchanger to direct a portion of the cold liquid desiccant to the desiccant distributor and a portion of the cold liquid desiccant to the basin.

18. The LDAC of claim 16 comprising a three way valve in fluid communication with the output of the hot common heat exchanger to direct a portion of the hot liquid desiccant to the desiccant distributor and a portion of the hot liquid desiccant to the basin.

19. The LDAC of claim 17 comprising another three way valve in fluid communication with the output of the hot common heat exchanger to direct a portion of the hot liquid desiccant to the desiccant distributor and a portion of the hot liquid desiccant to the basin.

20. The LDAC of claim 16 wherein at least one of the refrigerator portion or the concentrator portion comprises an intermediate module.

Patent History
Publication number: 20250067449
Type: Application
Filed: Aug 19, 2024
Publication Date: Feb 27, 2025
Inventors: John Hammond (New Castle, DE), Scott Kennedy (New Castle, DE), Lavanya Jakka (New Castle, DE), Thomas Backman (New Castle, DE)
Application Number: 18/808,648
Classifications
International Classification: F24F 3/14 (20060101); F24F 11/84 (20060101);