Patent Application
20090139254
1. Field of the Invention
This invention relates generally to desiccant rotor assisted air conditioning systems and dehumidification processes, and more particularly to a thermodynamic closed loop desiccant rotor system and process which utilizes at least one closed recirculation loop that provides interchangeable energy directly to the desiccant material, and various alternate rotor isolated zoning configurations in combination with various arrangements of energy exchange devices and refrigeration components to maximize the interchangeable and recovered energy capability and capacity through both closed thermodynamic cycles and open cycle processes for significantly improved efficiency and energy conservation.
2. Background Art
Desiccant assisted air conditioning systems are known in the art. Desiccant rotor technology provides effective and efficient dehumidification of air. In most desiccant rotor systems, ionic desiccant materials are adhered or cooked in situ onto a rotor substrate and the rotor rotates between at least two air streams to flow through two separate zones to provide dehumidification or humidification by alternating the energy in a gas phase change process. In one of the zones, the air delivered to the interior of a space to be conditioned crosses the desiccant material, which attracts and holds moisture in a wicking action to adsorb unwanted gases. As the desiccant wheel rotates and enters the second zone, the moist desiccant material is subjected to a regeneration air stream where vapor content, which is then vented away. It is a common practice to condition the air stream prior it entering the regeneration zone of the rotor. The added regeneration energy allows the air to react with the desiccant material in a thermodynamic chemical equilibrium process and reaction rate adequate to condition the desiccant material prior to rotating into the process air stream.
The useful energy and/or reaction rate between the air and the desiccant material is directionally proportional to the conditioning of the desiccant material. Typically, a great part of the energy added to condition the air is wasted and results in high energy consumption.
Conventional desiccant rotor technology typically incorporates a rotating desiccant wheel that rotates between two air streams to provide dehumidification or humidification by alternating the energy in a gas phase change process. In such systems, the process air delivered to the interior of a space to be conditioned crosses the desiccant material, which attracts and holds moisture. As the desiccant wheel rotates, the moist desiccant material enters the regeneration air stream where it is heated to release moisture, which is then vented away. Because humidity is a function of vapor pressure, desiccant materials have the ability to remove or add moisture adiabatically; a reversible thermodynamic process in which the energy exchanges result in substantially constant enthalpy equilibrium. The total desiccant open cycle is somewhat similar to a refrigerant vapor-compression cycle. In a desiccant and air system the heated regeneration air adds energy to the moistened desiccant in a de-sorption process and releases moisture in the regenerating crossing air stream in an adiabatic cooling process. When the desiccant rotates to the process air stream the pre-conditioned desiccant enables the sorption of water and dehumidifies the crossing process air and adiabatic re-heat is released in the air stream. This completes the desiccant vapor-compression open cycle.
Several other practices can be utilized to improve the regeneration of desiccant on the rotor and or diminish the energy usage. Refrigeration can be used to cool the air to a dew point and remove any elevated grain level and excess of humidity in the crossing air. It also can re-use the usually rejected condenser refrigerant energy to re-heat the air prior to entering the regeneration air to the rotor.
Heat recovery apparatus are also often used. They recover re-usable sensible heat from the regeneration exhaust air and transfer this heat to the regeneration intake air stream.
Desiccant applications are effective in separating the total air cooling process into two separate processes; latent and sensible energy. Although desiccant technology may sometimes benefit from its adiabatic desiccant re-heating effect provided in the process delivery (supply) air, quite often re-cooling of the process air is needed to provide adequate delivery (supply) air.
In the existing conventional rotor technology it is a common practice to regenerate the desiccant material in an open type process instead of a closed loop process. In the crossing process air stream, an open cycle is needed since the process involves conditioning the crossing air and separating unwanted gases. In a regeneration process, the useful and effective energy involves preparation of the desiccant prior to rotating it into the process air. In typical conventional application, a crossing agent such as outdoor air is utilized to carry the unwanted gases over to an exhaust and simultaneously regenerate the desiccant material and content. Most conventional regeneration processes typically utilize an open cycle system.
The heating of the regeneration air stream utilizing part of the surroundings of the isolated desiccant material as a carrying agent is required in a open cycle system and process to remove the unwanted vapors.
In the refrigerant compression closed cycle of the conventional air conditioning system, a compressor compresses refrigerant gas to increase its pressure and temperature in an isentropic adiabatic process. The refrigerant is then passed through a condenser coil where the superheated compressed refrigerant dissipates its heat to the crossing air stream condensing the refrigerant into a high-pressure liquid, which then flows through a metering device or expansion valve that restricts the high-pressure liquid and creates a reverse refrigerant adiabatic effect, after which, the refrigerant is discharged or suctioned to an evaporator coil at lower refrigerant temperature and pressure conditions, which enable the evaporator coil to absorb heat from the crossing air that is forced through the coil by the evaporator fan. The air exiting the evaporator coil is discharged as cool air and the refrigerant absorption process changes the refrigerant from liquid-gas to gas, which is then suctioned back to the compressor to complete the closed cycle.
The present invention is distinguished over the prior art in general by a thermodynamic closed loop desiccant rotor system and process which utilizes at least one closed recirculation loop that provides interchangeable energy directly to the desiccant material and utilized in various alternate rotor isolated zoning configurations, in combination with various arrangements of energy exchange devices and refrigeration components to maximize the interchangeable and recovered energy capability and capacity through both closed thermodynamic cycles and open cycle processes for significantly improved efficiency and energy conservation.
The present desiccant rotor system may be utilized in an air conditioning system for dehumidification, humidification, moisture removal, and capture of moisture, and it may also be utilized to remove unwanted gases such as carbon dioxide, carbon monoxide, hydrogen, and nitrogen, in the manner of a gas separator, gas accumulator, gas filtering apparatus, or water system accumulator.
In some of the drawing figures of the present invention, described in detail hereinafter, the heavier lines represent the air flow paths and the thinner lines represent the flow path of refrigerant.
Detailed descriptions of several preferred embodiments are provided herein having arrangements of components and desiccant rotors with zoning features for carrying out various processes. It is to be understood, however, that the present invention may be embodied in various forms and combinations. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, process, structure or manner.
As used herein, the term “air conditioning” is a general term meaning a system for controlling the temperature and humidity of air and other gases and includes dehumidification, humidification, and moisture release. Air conditioning systems for treating or conditioning and gases may include, for example, such systems as cooling systems, heating systems, gas separators, gas concentrators, and drinking water accumulators. As used herein, the term “conditioned air” is a general term and includes dehumidified air, humidified air, and cool or warm air, or a combination thereof. The term “process air” means any air that is to be processed by the present system, and may be pre-conditioned by various methods. The term “regeneration air” means any air that is used to regenerate the desiccant material. The term “delivery or supply air” means the air that is supplied to a spaced to be provided with conditioned air. The term “return air” means the air either returning from the conditioned space and may include newly introduced air.
The term “energy exchange device” means any device that enables the exchange of energy between two air streams in an air heating or cooling process. Examples of suitable “energy exchange devices” include: a refrigerant condenser, evaporator, heat pipes, water or radiator type coils, gas/oil fired device, heat exchangers, electric heater, thermoelectric heater, sensible energy exchanger, plated type heat exchanger, a second rotor, or solar energy device. The term “sensible heat exchanger” means any type of heat exchanger such as a plate type, rotor type, heat pipe any device which enables the exchange of energy between two airs streams, favoring sensible energy. The term “desiccant rotor” means any type of rotor device having the capability of interchanging either latent and/or sensible energy and/or moisture. The term “desiccant” means a drying substance or agent and may include materials such as silicas, aluminas, titanium, lithium chloride, zeolites, polymers, clay, molecular sieves, hydrophilic substances and sorbents. The term “compressor” is a device utilized in a refrigeration process to compress the refrigerant. This device can be modulating, capacity controlled or any combination of several compressors. The term “evaporator” is a refrigerant coil device in which the refrigerant adsorbs energy from a crossing air stream. The term “condenser” means a refrigerant coil device that dissipates its refrigerant energy in its crossing air stream.
It should be understood that in some of the arrangements described and shown hereinafter, the “energy exchange devices” are assigned different numerals of reference when referring to a specific type of heating or cooling energy exchange device, such as, for example, a refrigerant condenser coil or evaporator coil. In the following discussion, for purposes of example only, the invention will be described in various preferred forms, as an air conditioning system for dehumidification, humidification, moisture removal, and capture of moisture, however, it should be understood that the present invention is not limited to performing only that function. The present desiccant rotor system and process may also be utilized to remove unwanted gases such as carbon dioxide, carbon monoxide, hydrogen, and nitrogen, in the manner of a gas separator, gas accumulator, gas filtering apparatus, or water system accumulator.
Referring now to
In
The zone circulating fan 1 discharges air in an airflow path 3 that passes across the energy exchange device 0 where it is heated or cooled and exchanges its energy to achieve a higher or lower temperature and changed vapor condition. The conditioned air stream 4 leaving the energy exchange device passes across the isolated zone Z of the desiccant rotor 9 to directly condition the desiccant and moisture content. The desiccant material and content reacts to achieve an equilibrium state with the crossing air stream and the crossing air stream exits the isolated zone as air stream 2 having different lower or higher temperature and vapor conditions as compared to the entering air. The air stream 2 leaving the isolated zone of the rotor returns to the intake of the zone circulating fan 1 in a continuous closed loop thermodynamic heating or cooling process. The continuous closed loop thermodynamic process is a continuous recirculation loop that provides a constant source of added or removed heat energy which affects the desiccant temperature and vapor conditions.
Optionally, an amount of air can be introduced and/or exhausted anywhere in the continuous closed loop air steam, from any other zones or air paths crossing any part of the rotor or outside of the rotor. It should be understood that the rotor may have several isolated zones of desiccant material in fluid communication with several air streams in closed loop and/or open loop configurations. It should also be understood that the energy exchange device can exchange or interchange energy with several other air streams in closed loop and/or open loops, in the system or out of the system, also using water, air refrigerant, or other energy transferable fluid agents.
Referring now to
It should be noted that the heat energy exchange device designated by numeral 10, is designated by other numerals when referring to a specific type of heating or cooling energy exchange device, such as, for example, a refrigerant condenser coil or evaporator coil.
Desiccant zone Z4 is in fluid communication with a heater device 41 which receives regeneration air 40 from a regeneration air intake. Desiccant zone Z3 is in fluid communication with a process intake air 30, and over which process air from a process air intake crosses to be processed by the system.
As described above, the zone circulating fan 11 discharges air in an airflow path 13 that passes across the energy exchange device 10 where it is heated and exchanges its energy to achieve a desired vapor and temperature condition. The heated air stream 14 leaving the energy exchange device passes across the isolated zone Z1 of the desiccant rotor 9 to directly condition the desiccant and moisture content. The desiccant material and content reacts to achieve an equilibrium state with the crossing air stream and the crossing air stream exits the isolated zone as air stream 12 having different (lower) temperature and vapor conditions as compared to the entering air. The air stream 12 leaving the isolated zone of the rotor returns to the intake of the zone circulating fan 11 in a continuous closed loop. The continuous closed loop is a continuous recirculation loop that provides a constant source of added heat energy to affect the desiccant temperature and vapor conditions.
In this particular process the desiccant material in zone Z1 interchanges its energy in constant enthalpy equilibrium, and the air stream 12 leaving the zone Z1 results in an adiabatic cooling and humidification effect. As a result of the continuous recirculation loop and constant source of added energy into the closed loop process the desiccant and its content, temperature and vapor conditions absorbs most of the added heat from the heat energy exchange device 10.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of zone Z1 to the regeneration process zone Z4. The regeneration air flows from the air intake 40 enters the regeneration air heater 41, exits as heated regeneration air in airflow path 42, passes across the isolated regeneration zone Z4, and exits the other side of the isolated regeneration zone in air flow path 43 as regeneration exhaust air 45.
The desiccant which is rotated from the pre-conditioning zone Z1 to zone Z4 has been pre-conditioned to contribute to the equilibrium and reaction rate and direction of the reaction of the desiccant with the heated air stream 42, thereby accelerating the release of moisture in the crossing air stream 43 at zone Z4, and also reducing the amount of air required to be heated to provide an adequate regeneration process which results in regeneration energy savings. The regeneration process of zone Z4 and its respective air stream enables the evacuation of unwanted moisture in the regeneration exhaust air 45.
The desiccant material having reduced moisture and vapor content then rotates from regeneration zone Z4 to the process zone Z3. The process air from the intake 30 flows through the process air zone Z3 and exits the other side as process delivery air 31. In this process the conditioned desiccant enables the wick material to adsorb moisture in its crossing air stream. The constant enthalpy and heat sink effect of the desiccant provides an adiabatic heating and re-heat effect and dehumidifies the crossing air stream which leaves as the process delivery or supply air 31.
The usual adiabatic cooling effect of the regeneration process that typically occurs in a conventional open type system is not significant in the closed loop system, and the equilibrium achieved is facilitated by the direct heat transfer from the heat energy exchange device 10 at zone Z1.
In zone Z1, if the pre-conditioned desiccant material and content was elevated above the thermal and vapor pressure conditions different from the heated air stream 42 or desiccant conditions of zone Z4, then the desiccant and its content in reaction with the air will partially reverse direction as compared to a typical conventional regeneration air process.
In the conventional open type process the regeneration air is first heated, it then reacts with the desiccant content gradually and, after it achieves an equilibrium state, it releases its moisture content.
In the present process, pre-heating of the desiccant and content changes the rate of equilibrium and also the reaction equilibrium itself in the regeneration air stream. Unlike the conventional equilibrium state that usually occurs in the conventional process, the present process also make it possible to partially change the direction of the reaction.
Thus, the present process which pre-conditions the desiccant and its content changes the dynamics of the rate of equilibrium once rotated from a closed loop to an open flow regeneration process.
Referring now to
The zone circulating fan 21 discharges air in an airflow path 23 that passes across the cooling energy exchange device 20 where it is cooled to achieve a desired vapor and temperature condition. The cooled air stream 24 leaving the cooling energy exchange device passes across the isolated zone Z2 of the desiccant rotor 9 to directly condition the desiccant and moisture content. The desiccant material and content reacts to achieve an equilibrium state with the crossing air stream and the crossing air stream exits the isolated zone as air stream 22 having higher temperature and vapor conditions as compared to the entering air. The air stream 22 leaving the isolated zone of the rotor returns to the intake of the zone circulating fan 21 in a continuous closed loop. The continuous closed loop is a continuous recirculation loop that provides a constant source of removed heat energy to affect the desiccant temperature and vapor conditions.
In this particular process the desiccant material in zone Z2 interchanges its energy in constant enthalpy equilibrium, and the air stream 22 leaving the zone Z2 results in an adiabatic heating and dehumidification effect. The continuous recirculation closed loop and constant absorption process and removal of heat energy from the closed loop process results in diminishing the desiccant temperature and vapor conditions.
The usual adiabatic heating effect of the process air that typically occurs in a conventional open type system is not as significant in the closed loop system, and the equilibrium achieved is facilitated by the direct absorption of heat energy at zone Z2.
The cooled and dehumidified desiccant material then rotates from regeneration zone Z2 to the process air zone Z3. The process air from the intake 30 flows through the process air zone Z3 and exits the other side as process delivery or supply air 31. In this process the conditioned desiccant enables the wick material to adsorb moisture in its crossing air stream. The pre-conditioning of the desiccant accelerates the adsorption of moisture in the crossing air stream 30 which leaves as the process delivery or supply air 31. The process delivery or supply air 31 is adiabatically heated prior to leaving.
In zone Z2, if the pre-conditioned desiccant material and content was lowered below the thermal and vapor pressure conditions of the process air stream 30, then the desiccant and its content in reaction with the air will partially reverse direction as compared to a typical conventional process air process.
In the conventional open type process the process air is first cooled, it then reacts with the desiccant content gradually and, after it achieves an equilibrium state, it results in an average reaction of adsorption of its moisture content.
In the present process, pre-cooling of the desiccant and content changes the rate of equilibrium and also the reaction equilibrium itself in the crossing air stream. Unlike the conventional equilibrium state that usually occurs in the conventional process, the present process also makes it possible partially change the direction of the reaction.
Thus, the present process which pre-conditions the desiccant and its content changes the dynamics of the rate of equilibrium once rotated from the closed loop to the open flow regeneration process.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of zone Z3 to the regeneration process zone Z4. The regeneration air flows from the air intake 40 enters the regeneration air heater 41, exits as heated regeneration air in airflow path 42, passes across the isolated regeneration zone Z4, and exits the other side of the isolated regeneration zone in air flow path 43 as regeneration exhaust air 45.
In this arrangement, regeneration desiccant zone Z4 is in fluid communication with a regeneration heater 41 and suction side of a regeneration fan 47. The regeneration intake air 40 flows through a sensible heat energy exchange device 25 and is directed via air flow path 46 to the regeneration heater 41. Air leaving the regeneration heater 41 flows through the isolated regeneration desiccant zone Z4 of the rotor 9 via air flow path 42 and air leaving the desiccant zone Z4 enters the suction side of the regeneration fan 47 via air flow path 43 and is discharged by the regeneration fan as regeneration exhaust air 45.
In the closed loop cycle and process, a separate isolated air stream 24 leaves the sensible heat exchange device 25 and passes across the isolated desiccant zone Z2 of the rotor 9 and leaves the isolated zone via air flow path 22 and enters the suction side of the closed loop circulating fan 21. The air discharged from the circulating fan via air flow path 23 also enters the sensible heat exchange device 25 as a separate alternate crossing air stream 23 and exits the device as cooler air stream 24 and continuously re-circulates.
The process air from the process air intake 30 flows through the process air desiccant zone Z3 of the rotor and leave as process air delivery air 31.
Air from the regeneration intake air 40 enters first into the sensible heat exchanger device 25 where interchanges its sensible energy with the alternate crossing air stream 23 of the closed loop. As a result of the temperature differential between the crossing air streams 40 and 23, the crossing air 23 is cooled in some equilibrium aspect and discharged via air path 24.
This process re-uses the remaining pre-conditioned desiccant sensible energy heat sink capacitance, in part, by heating the air stream 46. The air in air stream 46 contains recovered energy and then crosses the regeneration heater 41 which adds and augments the sensible heat energy into its leaving air stream 42. This air then crosses the isolated desiccant regeneration zone Z4 where constant enthalpy equilibrium energy is interchanged from the desiccant and moisture content in zone Z4. The regeneration air 43 leaving zone Z4 is humidified and cooled adiabatically. The air is then discharged by the regeneration fan 47 as regeneration exhaust air 45.
The separate air stream 23 of the closed loop which also crosses the sensible heat exchanger 25, leaves as cooler air in stream 24. The interchanged sensible energy occurring in the heat exchanger 25 which causes the heating of the air stream 46 also simultaneously causes a cooling effect of the air stream 23. The air stream 24 of the closed loop leaving the sensible heat exchanger 25 enters the isolated desiccant zone Z1 of the rotor 9 where the desiccant material interchanges its sensible energy with the crossing air to pre-condition its heat capacitance and content. The air leaving the isolated desiccant zone Z1 absorbs part of the elevated temperature heat capacitance and content of the desiccant. The re-heated air leaves as air path 22 to the intake of the closed loop circulating fan 21 and is discharged via air path 23 and enters the sensible heat exchanger 25 and continuously re-circulates.
In this aspect of the process, the sensible energy is interchanged through the heat exchanger 25 between the entering air stream 40 and the air stream from the closed loop 23 into sensible energy and temperature equilibrium. Thus, the desiccant in zone Z1 is cooled and the interchanged energy results in the effect of heating the adjacent air stream 46.
Therefore, the elevated desiccant heat capacitance and content from the isolated zone Z1 is cooled through the effect of the sensible heat exchanger 25 and its crossing air stream 40. The heat recovery process from the sensible heat exchanger 25 results in pre-conditioning of the desiccant material in zone Z1. Sensible energy is removed from the desiccant in zone Z1 and is recovered in series into the air regeneration air stream 46.
The energy exchange device 25 can be any type of apparatus to remove, recuperate, recover or exchange or interchange sensible or latent heat energy and moisture content in its crossing air stream. For example, such devices as: refrigerant evaporator, water or radiator type coils, thermoelectric cooling, sensible energy exchanger, plated type, second rotor, or heat pipe apparatus. In this particular arrangement, the energy exchange device 25 provides an air cooling process capable of removing heat energy in the closed loop.
In this particular process the desiccant material in zone Z1 interchanges its energy in constant enthalpy equilibrium, and the air stream 22 leaving the zone Z2 results in an adiabatic heating and dehumidification effect. The continuous recirculation closed loop and constant absorption process and removal of heat energy from the closed loop process results in diminishing the desiccant temperature and vapor conditions.
The usual adiabatic heating effect of the process air that typically occurs in a conventional open type system is not significant in the closed loop system, and the equilibrium achieved is facilitated by the direct absorption of heat energy at zone Z1.
The cooled and dehumidified desiccant material then rotates from zone Z1 to the to the separate process air zone Z3 and the desiccant material and remaining content from zone Z4 rotates to the closed loop zone Z1
The process air from the intake 30 flows through the process air zone Z3 and exits the other side as process delivery or supply air 31. In this process the conditioned desiccant enables the wick material to adsorb moisture in its crossing air stream. The pre-conditioning of the desiccant accelerates the adsorption in the crossing air stream 30 which leaves as the process delivery or supply air 31. The process delivery or supply air 31 could be also be adiabatically heated and also could be re-cooled through the desiccant heat sink effect and energy exchange prior to leaving as the process delivery or supply air 31.
If the pre-conditioned desiccant material and content was lowered below the thermal and vapor pressure conditions of the process air stream 30, then the desiccant and its content in reaction with the air will partially reverse direction as compared to a typical conventional process air process.
In the conventional open type process the process air is first cooled, it then reacts with the desiccant content gradually and, after it achieves an equilibrium state, it results in an average reaction of adsorption of its moisture content.
In the present process, pre-cooling of the desiccant and moisture content changes the rate of equilibrium and also the reaction equilibrium itself in the crossing air stream. Unlike the conventional equilibrium state that usually occurs in the conventional process, the present process also make it possible to partially change the direction of the reaction.
Thus, the present process which pre-conditions the desiccant and its moisture content changes the dynamics of the rate of equilibrium once rotated from the closed loop to the open flow regeneration process.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of zone Z3 to the regeneration process zone Z4. The desiccant which is rotated from the process air zone Z3 to zone Z4 has been pre-conditioned to achieve moisture content, temperature and vapor conditions which are determined to contribute to the equilibrium and reaction rate and direction of the reaction of the desiccant with the crossing air stream, thereby facilitating its ability to react in a constant enthalpy interchangeable energy adiabatic cooling process, and reduces the amount of air required to be heated to provide an adequate regeneration process.
The combined heat exchanger 25 and regeneration heater 25 heats the entering air 40 and discharges the elevated temperature air into the rotor desiccant zone Z4. The conditioning of the air stream 42 enables the desiccant and moisture content to react with its crossing air stream in a constant enthalpy interchangeable energy adiabatic cooling process and results in a humidified and cooling effect on the air 43 leaving the desiccant zone Z4 and the regeneration process of zone Z4 and its air streams enable evacuation of unwanted moisture in the regeneration exhaust air 45.
In the first closed loop, the energy exchange device 10 is a heat exchange device capable of providing heat energy and the initial isolated zone of desiccant material for the isolated closed loop is identified as Z1. The zone circulating fan 11 discharges air in an airflow path 13 that passes across the energy exchange device 10 where it is heated and exchanges its energy to achieve a desired vapor and temperature condition. The heated air stream 14 leaving the energy exchange device passes across the isolated zone Z1 of the desiccant rotor 9 to directly condition the desiccant and moisture content. The desiccant material and content reacts to achieve an equilibrium state with the crossing air stream and the crossing air stream exits the isolated zone as air stream 12 having higher temperature and vapor conditions as compared to the entering air. The air stream 12 leaving the isolated zone of the rotor returns to the intake of the zone circulating fan 11 in a continuous closed loop that provides a constant source of added heat energy to affect the desiccant temperature and vapor conditions.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of zone Z1 to the regeneration process zone Z4. The regeneration air flows from the air intake 40 enters the regeneration air heater 41, exits as heated regeneration air in airflow path 42, passes across the isolated regeneration zone Z4, and exits the other side of the isolated regeneration zone in air flow path 43 as regeneration exhaust air 45.
The preconditioned desiccant material rotates out of zone Z4 to the zone Z2 which is in fluid communication with the second closed loop. In the second closed loop, the energy exchange device 20 is a cooling energy exchange device capable of removing heat energy, and is fluid communication with zone Z2 of the desiccant rotor 9. The zone circulating fan 21 discharges air in an airflow path 23 that passes across the cooling energy exchange device 20 where it is cooled to achieve a desired vapor and temperature condition. The cooled air stream 24 leaving the cooling energy exchange device passes across the isolated zone Z2 of the desiccant rotor 9 to directly condition the desiccant and moisture content. The desiccant material and content reacts to achieve an equilibrium state with the crossing air stream and the crossing air stream exits the isolated zone as air stream 22 having higher temperature and vapor conditions as compared to the entering air. The air stream 22 leaving the isolated zone of the rotor returns to the intake of the zone circulating fan 21 in a continuous closed loop that provides a constant source of removed heat energy to affect the desiccant temperature and vapor conditions.
The preconditioned desiccant material rotates out of zone Z2 to the process air desiccant zone Z3 which is in fluid communication with the process air intake 30, and process air from the process air intake crosses over the desiccant zone Z3 and exits the other side as process delivery or supply air 31, and as the desiccant rotor 9 continues to rotate, the desiccant material rotates out of zone Z3 to return to the isolated desiccant zone Z1.
The heating and cooling process of the first and second closed loops and the regeneration process and conditioning of the process delivery or supply air 31 can occur simultaneously.
As stated above, this particular arrangement is a combination of the arrangements of
In this arrangement, the energy exchange device is a desiccant rotor energy exchange device 50 having a heating regeneration desiccant zone 10 in fluid communication with the closed heating loop (the inner loop) which functions similar to the heat exchanger 10 of
In the first or outer closed loop, the zone circulating fan 21 draws air across the isolated desiccant zone Z1 of the desiccant rotor 9 and discharges it in an airflow path 23 that passes across the heating regeneration desiccant zone 10 of the rotor energy exchange device 50 to achieve a desired vapor and temperature condition, leaves the desiccant zone 10 of the rotor energy exchange device 50 and returns across the isolated zone Z1 of the desiccant rotor 9 in a continuous closed loop. The first or outer continuous closed loop is a continuous recirculation loop that provides a constant source of additional heat energy to affect the desiccant temperature and vapor conditions.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of zone Z1 to the regeneration process zone Z4. Regeneration desiccant zone Z4 of the desiccant rotor 9 is in fluid communication with a regeneration heater device 41 and suction side of a regeneration fan 47. The regeneration intake air 40 flows through the heater device 41 via air flow path 42 through the isolated regeneration desiccant zone Z4 of the rotor 9 and air leaving the desiccant zone Z4 enters the suction side of the regeneration fan 47 via air flow path 43 and is discharged by the regeneration fan as regeneration exhaust air 45.
As the desiccant rotor 9 rotates from the regeneration desiccant zone Z4 to zone Z2 the regenerated desiccant material is in the path of the second closed loop (the inner loop). In the second or inner closed loop, the zone circulating fan 11 draws air across the isolated desiccant zone Z2 of the desiccant rotor 9 and discharges it in an airflow path 13 that passes across the pre-cooling regeneration desiccant zone 20 of the rotor energy exchange device 50 to achieve a desired vapor and temperature condition, leaves the desiccant zone 20 of the rotor energy exchange device 50 and returns across the isolated zone Z2 of the desiccant rotor 9 in a continuous closed loop that provides constant heat energy removal to affect the desiccant temperature and vapor conditions.
The desiccant rotor 9 then rotates from the desiccant zone Z2 to zone Z3 where the regenerated and pre-cooled desiccant material is in the path of the process air desiccant zone Z3 which is in fluid communication with the process air intake 30, and process air from the process air intake crosses over the desiccant zone Z3 and exits the other side as process delivery or supply air 31. As the desiccant rotor 9 continues to rotate, the desiccant material rotates out of zone Z3 to return to the isolated desiccant zone Z1.
The heating and cooling process of the first and second closed loops and the regeneration process and conditioning of the process delivery or supply air 31 can occur simultaneously. In other words, as the regeneration sequence occurs in the desiccant rotor regeneration zone Z4 another process occurs in isolated zone Z2 and zone Z1. In these two zones, two separate air streams exist and interchange energy through the regeneration zones 10 and 20 of the second desiccant rotor energy exchange device 50.
As the second desiccant rotor energy exchange device 50 rotates, the cooled air stream 23 from zone Z1 of the rotor 9 passes across the regeneration zone 10 of the rotor 50, and is re-heated by the desiccant material which was regenerated at zone 20 by the heated air stream 13 from zone Z2 of the rotor 9.
The desiccant in the regeneration zone 10 of the desiccant rotor energy exchange device 50 is regenerated and provides the energy to re-heat and the cooled air stream 23 which crosses the regeneration zone 10 of the desiccant rotor energy exchange device. Optionally, depending on the rotor type selection, some latent interchangeable energy could also occur to permit latent energy exchange between both air streams 23 and 13. This would cause the leaving air 24 not only to be heated with sensible energy recovery but also through the ability of its desiccant to also have an adiabatic heating effect caused by the interchangeable energy exchange of the captured moisture content into its desiccant wick material. This captured moisture content also reduces moisture in proportion to its crossing air stream 24 and becomes part of the energy equilibrium entering the isolated zone Z1 of the desiccant rotor 9.
The moisture reset feature that occurs between the zones Z2 and zone Z1 of the rotor 9 and the regeneration zones 20 and 10 of the of the second desiccant rotor energy exchange device 50 enables the desiccant content and moisture conditions in zone Z1 to be reduced in total heat capacitance. The reduced heat capacitance diminishes the usual unwanted re-heating effect of the desiccant material and content when the rotor 9 is rotated from zone Z2 to the process zone Z3 and the heat of the processed air delivery or supply stream 31 is diminished due to the diminished heat sink energy the rotated desiccant and content. The latent heat capability of the second desiccant rotor energy exchange device 50 enables extra capability of energy exchange. Thus, augmented adiabatic sensible and cooling desiccant effect is interchanged for either the dissipation or capturing of moisture. This reset process augments the total effective cooling.
As stated above, this particular arrangement is a combination of the arrangements of
In the first closed loop, the zone circulating fan 11 draws air across the isolated desiccant zone Z1 of the desiccant rotor 9 and discharges it in an airflow path 13 that passes across the heat energy exchange device 10 where it is heated to achieve a desired higher vapor and temperature condition, and the heated air leaves the heat energy exchange device 10 in air flow path 14, crosses the isolated zone Z1 of the desiccant rotor 9, and returns to the suction side of the zone circulating fan 11 in a continuous closed loop that provides a constant source of additional heat energy to affect the desiccant temperature and vapor conditions.
In this arrangement, regeneration desiccant zone Z4 is in fluid communication with a regeneration heater device 41 and suction side of a regeneration fan 47. The regeneration intake air 40 flows through a sensible heat energy exchange device 25 and is directed via air flow path 46 to the regeneration heater 41. Air leaving the regeneration heater 41 flows through the isolated regeneration desiccant zone Z4 of the rotor 9 via air flow path 42 and air leaving the desiccant zone Z4 enters the suction side of the regeneration fan 47 via air flow path 43 and is discharged by the regeneration fan as regeneration exhaust air 45.
In the second closed loop, the zone circulating fan 21 draws an isolated air stream 22 through the sensible heat exchange device 25, across the isolated desiccant zone Z2 of the rotor 9, and discharges it as a crossing air stream 23 back through the sensible heat exchange device 25 and across the isolated desiccant zone Z2 of the rotor 9 and to the suction side of the closed loop circulating fan 21. Thus, the air discharged from the circulating fan via air flow path 23 also enters the sensible heat exchange 25 as a separate alternate crossing air stream 23 and exits the device as a cooler air stream 24.
The process air from the process air intake 30 flows through the process air desiccant zone Z3 of the rotor and leave as process air delivery or supply air 31.
When the desiccant material is in zone Z1 it interchanges its energy in constant enthalpy equilibrium, facilitated by the direct absorption of heat energy from the air stream of the closed loop.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of zone Z1 to the regeneration process zone Z4. The regeneration air 40 enters into the sensible heat exchange device 25 where it interchanges its sensible energy with the adjacent crossing air stream 23 of the closed loop and the air leaving the regeneration heater 41 flows through the isolated regeneration desiccant zone Z4 of the rotor 9 via air flow path 42 and air leaving the desiccant zone Z4 enters the suction side of the regeneration fan 47 via air flow path 43 and is discharged by the regeneration fan as regeneration exhaust air 45. The temperature and moisture conditions of the desiccant material pre-conditioned in zone Z1 accelerate the release of moisture in the crossing air stream 43. If the desiccant material and content pre-conditioned in zone Z1 was elevated above the condition of the heated air stream 42 then the desiccant reaction would reverse direction in some aspect and add to the release and acceleration rate of moisture in its crossing air stream 43. Depending upon the pre-conditioning of the desiccant in zone Z1 the leaving air 43 could be adiabatically cooled or heated through the desiccant heat sink effect and energy. The regeneration zone Z4 and open and closed loop air streams also facilitate the evacuation of unwanted moisture in the regeneration exhaust air 45.
The desiccant rotor 9 rotates from zone Z4 to the zone Z2 and the augmented and elevated desiccant material from zone Z4 is in communication with regeneration closed loop zone Z2. The process in the second closed loop uses the heat sink capacitance, of the zone Z2, to heat the air stream 46 through the adjacent side of the heat exchanger 25 as described in
As result of temperature differential the crossing air 23 is heated at the heat energy exchange device 25 discharged via air path 24. This process re-uses the remaining desiccant sensible energy heat sink capacitance and pre-condition in part by heating the air stream 46. The air stream 46 crossing the regeneration heater 41 adds and augments the sensible heat energy into the leaving air stream 42 which then crosses the desiccant regeneration isolated zone Z4 and interchanges its energy in constant enthalpy equilibrium. The air 43 leaving zone Z4 is humidified and cooled adiabatically and discharged as regeneration exhaust air 45.
The desiccant rotor 9 then rotates from the desiccant regeneration zone Z2 to zone Z3 where the regenerated and pre-cooled desiccant material is in the path of the process air desiccant zone Z3 which is in fluid communication with the process air intake 30, and process air from the process air intake crosses over the desiccant zone Z3 and exits the other side as process delivery or supply air 31. Pre-conditioning of the desiccant material and moisture content accelerates the adsorption of moisture in the crossing air stream 30. As the desiccant rotor 9 continues to rotate, the desiccant material rotates out of zone Z3 to return to the isolated desiccant zone Z1.
This process in particular reduces the heat sink and transferable energy usually occurring in typical conventional desiccant rotor applications and significantly diminishes the desiccant re-heat effect in the process delivery or supply air stream that often occurs.
The heating and cooling process of the first and second closed loops and the regeneration process and conditioning of the process delivery or supply air 31 can occur simultaneously. In other words, as the regeneration sequence occurs in the desiccant rotor regeneration zone Z4 another process occurs in isolated zone Z2 and zone Z1.
As stated above, this particular arrangement is a combination of the arrangements of
In this arrangement, the heat energy exchange device is a condenser coil 60 disposed in heat exchange relation in the closed heating loop (the outer loop) and the cooling energy exchange device is an evaporator coil 70 disposed in heat exchange relation in the closed cooling loop (the inner loop).
In the first or outer closed loop, the zone circulating fan 21 draws air across the isolated desiccant zone Z1 of the desiccant rotor 9 and discharges it in an airflow path 23 that passes across the condenser coil 60 to achieve a desired vapor and temperature condition, leaves the condenser coil 60 in air flow path 24, and returns across the isolated zone Z1 of the desiccant rotor 9 in a continuous closed loop. The first or outer continuous closed loop is a continuous recirculation loop that provides a constant source of additional heat energy to affect the desiccant temperature and vapor conditions.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of zone Z1 to the regeneration process zone Z4. The regeneration desiccant zone Z4 of the desiccant rotor 9 is in fluid communication with the suction side of the regeneration fan 47 and the regeneration fan draws regeneration intake air 40, through an optional refrigerant condenser 61, which leaves in air flow path 51 that flows through an optional heater device 41 and exits via air flow path 42 through the isolated regeneration desiccant zone Z4 and is discharged by the regeneration fan as regeneration exhaust air 45. In this particular application, regeneration intake air may be any pre-conditioned air or outside air. Outdoor air 40 in a separate side or bypass system crosses an optional condenser coil 62 and is discharged through a damper 110 or fan as discharge air 53. Optionally, the discharge air 53 may be re-joined with the regeneration exhaust air 45 and may also be connected with the regeneration fan 47.
As the desiccant rotor 9 rotates, the pre-conditioned desiccant material rotates out of regeneration process zone Z4 to the isolated desiccant zone Z2 which is in communication with the second (inner) closed loop. In the second or inner closed loop, the zone circulating fan 11 draws air across the isolated desiccant zone Z2 of the desiccant rotor 9 and discharges it in an airflow path 13 that passes across evaporator coil 70 to achieve a desired vapor and temperature condition, leaves the evaporator coil 70, and returns across the isolated zone Z2 of the desiccant rotor 9 in a continuous closed loop that provides constant heat energy removal to affect the desiccant temperature and vapor conditions.
The desiccant rotor 9 then rotates from the desiccant regeneration zone Z2 to zone Z3 where the regenerated and pre-cooled desiccant material is in the path of the process air desiccant zone Z3 which is in fluid communication with the intake process air 30, and process air 30 crosses over an optional evaporator coil 71 and exits in air stream 55 which crosses the isolated desiccant zone Z3 of the rotor 9 and is discharged as air stream 56 which crosses another optional evaporator coil 72, and is discharged as process delivery or supply air 31. As the desiccant rotor 9 continues to rotate, the desiccant material rotates out of zone Z3 to return to the isolated desiccant zone Z1.
The air flow paths have been discussed above and will not be described again in detail to avoid repetition. In the refrigerant compression closed cycle of the refrigeration system, the compressor 80 compresses refrigerant gas to increases its pressure and temperature in an isentropic adiabatic process. The refrigerant is then passed through the condenser coils 62, 61, 60 where the superheated compressed refrigerant dissipates its heat to the crossing air stream and the refrigerant is condensed into a high-pressure liquid. The condenser coils reject the evaporator heat load, the evaporator superheat, and the heat of compression generated by the compressor. The refrigerant after dissipating its heat through the condensing coils approaches the metering device 81 where the pressure of the liquid is reduced to a lower evaporator pressure condition. When the liquid is expanded into the evaporator coils through the output orifice of the metering device 81, the temperature and pressure of the refrigerant liquid is reduced. Although only one expansion valve is shown in the drawings, it should be understood that an expansion valve may be installed at each evaporator coil.
As mentioned above, the metering device or expansion valve or valves restrict the high-pressure liquid and creates a reverse refrigerant adiabatic effect, after which, the refrigerant is discharged or suctioned to the evaporator coil or evaporator coils 70, 71, 72 at lower refrigerant temperature and pressure conditions, which enable the evaporator coils to absorb heat from the crossing air that is forced through the coil by the evaporator fan. The air exiting the evaporator coils is discharged as cool air and the refrigerant absorption process changes the refrigerant from liquid-gas to gas, which is then suctioned back to the compressor to complete the closed cycle.
Referring again to
The regeneration intake air 40, which may be an alternate air stream or outdoor air crosses the second condenser coil 61 and/or coil 62 which dissipate their heat into the crossing air stream which leaves in air flow path 51 that flows through the optional heater device 41 where it is additionally heated and exits via air flow path 42 through the isolated regeneration desiccant zone Z4 where it interchanges its energy with the desiccant and leaves the rotor as regenerated exhaust air 43. This air interchanges its energy through an adiabatic cooling effect and moisture is also dissipated also in the crossing air 43. The air stream 43 is then discharged by the regeneration fan as regeneration exhaust air 45.
Simultaneously as this sequence occurs in the desiccant rotor regeneration zone Z4 another process occurs in isolated desiccant zones Z2 and Z1. In these zones, two separate air streams exist and interchange refrigerant energy through the evaporator coil 70 and condenser coil 60 of the refrigeration system.
In the first or outer closed loop, the air stream 14 enters the isolated desiccant zone Z1 of the desiccant rotor 9 where the desiccant has been preconditioned by the process air stream prior to rotation to have a lowered temperature and elevated moisture content. The crossing air 14 flows through the isolated rotor zone Z1, which gradually heats the desiccant. This energy exchange also results in a cooling effect caused, in part, by the heat sink effect and also caused by an adiabatic cooling effect, thereby releasing some moisture in the air stream leaving the isolated desiccant zone Z1. This air enters the intake of the re-circulating fan 11 and the cooled air 13 is discharged to enter the condenser coil 60. As previously mentioned the condenser coil 60 dissipates its refrigerant energy to the crossing air stream 13, thereby heating the air stream 14 leaving the condenser coil. The heated air stream 14 re-enters the isolated desiccant zone Z1 of the rotor 9 in the recirculating closed loop process described above.
In the second (inner) closed loop, the air stream 24 crosses the isolated zone Z2 of the rotor 9. The desiccant in this isolated zone has been preconditioned from the regeneration air stream at desiccant zone Z4 prior to rotation. In this zone, the desiccant temperature is elevated and substantially dry. The crossing air 24 cools the desiccant material, and the air 23 leaving zone Z2 is heated as a result of the energy exchange process. The heated air 23 is then discharged by the zone circulating fan 21 to cross the evaporator coil 70 and re-enters the isolated desiccant zone Z4 of the rotor 9 in the closed loop process described above.
The transferred and added energy caused by the isolated loops and refrigeration energy exchanges results in the transport of sensible energy from the isolated zone Z2 to isolated zone Z1. As the desiccant is rotated from zone Z1 to zone Z4, the reset of temperature and vapor conditions facilitate preparing it for the next regeneration process.
The heat transfer feature between the zones Z2 and Z1 enables the desiccant and moisture conditions to be reduced in total heat capacitance which diminishes the unwanted re-heat effect of the desiccant when the rotor 9 is rotated from zone Z2 to the process zone Z3. The process intake air 30 flows across the optional evaporator coil 71 absorbs energy through the crossing air stream and the leaving air 55 is cooled before entering zone Z3 as result of the refrigeration evaporating process and facilitates the absorption of moisture as it crosses zone Z3. The air stream leaving zone Z3 and discharged as process delivery or supply air 31 is also diminished in heat due to the heat sink and the effect from the rotated pre-conditioned desiccant from zone Z2 . This heat transfer process augments the total effective cooling. The air 56 leaving zone Z3 could be re-cooled by the second optional evaporator coil 72 to re-capture this heat effect or simply cool the leaving delivery or supply air 31.
It should be understood, that the refrigeration system may be provided without the optional condenser coils 62 and/or 61 and the evaporator coils 72 and/or 71, or may utilize any number of coils connected in a series or parallel sequence or combination thereof. It should also be understood that the condenser coils may be combined as one device and/or may be controlled through either its crossing air volume and/or valves may be provided to redirect the refrigerant heat toward other condenser coils.
In this modification, the intake process air 30 first crosses the optional evaporator coil 71 and the air 55 leaving the evaporator coil crosses through the isolated zone Z3 of the rotor 9 and is discharged via air stream 56 as the process delivery or supply air 31. The air 55 leaving the evaporator coil can also flow through an optional bypass damper 93 via ducting 91 to bypass the zone Z3 and rejoin with the air stream 56 via ducting 92 to mix with the air stream 56 and be discharged as the process delivery or supply air 31. This optional bypass air path bypasses the rotor zone Z3 to controls the sensible cooling effect caused by the optional evaporator coil 71 and/or to diminish the dehumidification effect caused by the desiccant zone Z3.
In this arrangement it should be noted that rotation of the desiccant rotor 9 indicated by arrow 8 is shown to be in a clockwise direction. In the first closed loop cycle and process, the closed loop circulating fan 11 conducts a separate isolated air stream in a flow path 13 across a condenser coil 60 which dissipates its refrigerant energy to the crossing air stream, thereby heating the air stream, and the heated air stream 14 crosses the isolated desiccant zone Z1 of the rotor 9 and returns to the suction side of the circulating fan in a continuous closed loop that provides constant added heat energy to affect the desiccant temperature and vapor conditions.
The process intake air 30, which may be any pre-conditioned air or outside air, flows through the desiccant zone Z4 of the rotor, leaves the rotor as regenerated exhaust air 56 which crosses an evaporator coil 72, leaves the evaporator coil in air flow path 96 which then crosses desiccant zone Z3 of the rotor and is discharged as process delivery or supply air 31.
Outdoor air 52 in a separate air flow path or bypass system crosses an optional condenser coil 62 and is discharged as discharge air 53.
The air flow paths have been discussed above and will not be described again in detail to avoid repetition. In the closed loop, the air stream 14 crosses the isolated zone Z1 where the desiccant material has been preconditioned at zone Z3 to have elevated moisture content and lower temperature conditions. The crossing air 14 flows through the isolated rotor zone Z1, which gradually heats the desiccant and in increases moisture content, as described above with reference to
At the start of the regeneration process the rotor 9 rotates such that desiccant material at isolated zone Z1 is pre-wetted and preconditioned by the process at rotor zone Z3. The pre-conditioned desiccant which was located at isolated zone Z1 is rotated to the regeneration rotor zone Z4 and then to zone Z3 continuously at a controlled speed.
In the refrigerant compression closed cycle of the refrigeration system, the compressor 80 compresses refrigerant gas to increases its pressure and temperature in an isentropic adiabatic process. The refrigerant is then passed through the condenser coils 62 and 60 where the superheated compressed refrigerant dissipates its heat to the crossing air streams 52 and the refrigerant is condensed into a high-pressure liquid. The condenser coils reject the evaporator heat load, the evaporator superheat, and the heat of compression generated by the compressor. The air stream 53 leaving the condenser coil 62 and the air stream 65 leaving the condenser coil 60 are heated. The refrigerant after dissipating its heat through the condenser coils approaches the metering device 81 where the pressure of the liquid is reduced to a lower evaporator pressure condition. When the liquid is expanded into the evaporator coil 72 through the output orifice of the metering device 81, the temperature and pressure of the refrigerant liquid is reduced. Although only one evaporator coil and expansion valve is shown in the drawings, it should be understood that more than one coil may be provided and an expansion valve may be installed at each evaporator coil.
The process intake air 30 crosses the isolated regeneration zone Z4 of the rotor 9 where the crossing interchanges its energy with the preconditioned desiccant and exits the rotor as regenerated exhaust air 56 which interchanges its energy through an adiabatic cooling effect and moisture is dissipated into the crossing air 56. The pre-conditioning of the desiccant material in zone Z1 also affects the rate and equilibrium of moisture release and heat, as described in full in
As mentioned above, the metering device or expansion valve or valves restrict the high-pressure liquid and creates a reverse refrigerant adiabatic effect, after which, the refrigerant is discharged or suctioned to the evaporator coil or evaporator coils 72 at lower refrigerant temperature and pressure conditions, which enable the evaporator coil(s) to absorb heat from the crossing air that is forced through the coil(s) by the evaporator fan. The air exiting the evaporator coil(s) is discharged as cool air and the refrigerant absorption process changes the refrigerant from liquid-gas to gas, which is then suctioned back to the compressor to complete the closed cycle.
The outdoor condenser fan circulating the air through the condenser coil 62 can be modulated to concentrate the refrigerant energy and capacity towards the condenser coil 60. This would augment the heat intensity and capacity upon need. Optionally, the closed loop circulating fan 21 may be modulated to also control the heat capacity caused by the refrigerant heat of the condenser coil 60. An additional cooling coil may also be provided in the delivery or supply air stream 31.
It should be understood, that the refrigeration system may be provided without the optional condenser coils 62 and/or 60 and the evaporator coil 72, or may utilize any number of coils connected in a series or parallel sequence or combination thereof. It should also be understood that the condenser coils may be combined as one device, and/or valves may be provided to control refrigerant capacity or to change the series sequence of the condenser coils.
Outdoor air 52 in a separate air flow path or bypass system crosses an optional condenser coil 62 and is discharged as discharge air 53.
In the first closed loop cycle and process, the closed loop circulating fan 11 conducts a separate isolated air stream in a flow path 13 across a condenser coil 60 which dissipates its refrigerant energy to the crossing air stream, thereby heating the air stream, and the heated air stream 14 crosses the isolated desiccant zone Z1 of the rotor 9 and returns to the suction side of the circulating fan in a continuous closed loop that provides constant added heat energy to affect the desiccant temperature and vapor conditions.
In the second closed loop, the zone circulating fan 21 conducts a separate isolated air stream in a flow path 23 across an evaporator coil 70 which cools the air stream, and the cooled air stream 24 crosses the isolated desiccant zone Z2 of the desiccant rotor 9 and returns to the suction side of the zone circulating fan 21 in a continuous closed loop that provides constant heat energy removal to affect the desiccant temperature and vapor conditions.
In this arrangement, the process intake air 30, which may be any pre-conditioned air or outside air, crosses a second condenser coil 110, leaves the condenser coil in air flow path 51, flows through the desiccant zone Z4 of the rotor, leaves the rotor as regenerated exhaust air 56 which crosses an evaporator coil 72, leaves the evaporator coil in air flow path 96 which then crosses a third condenser coil 115 and leaves the condenser in air flow path 120 and is discharged as process delivery or supply air 31.
The air flow paths have been discussed above and will not be described again in detail to avoid repetition. In the closed loop, the air stream 14 crosses the isolated zone Z1 where the desiccant material has been preconditioned at zone Z3 to have elevated moisture content and lower temperature conditions. The crossing air 14 flows through the isolated rotor zone Z1, which gradually heats the desiccant and in increases moisture content. This energy exchange also results in a cooling effect on the desiccant material caused by the heat sink effect and by the adiabatic cooling effect achieved by releasing some moisture in the crossing air stream.
At the start of the regeneration process the rotor 9 has rotated such that desiccant material at isolated zone Z1 is pre-wetted and preconditioned by the process at rotor zone Z3. The pre-conditioned desiccant which was located at isolated zone Z1 is rotated to the regeneration rotor zone Z4 and then to zone Z3 continuously at a controlled speed.
In the refrigerant compression closed cycle of the refrigeration system, the compressor 80 compresses refrigerant gas to increases its pressure and temperature in an isentropic adiabatic process. The refrigerant is then passed through the condenser coils 62, 60, 110 and 115 where the superheated compressed refrigerant dissipates its heat to the crossing air streams condensing the refrigerant into a high-pressure liquid. The condenser coils reject the evaporator heat load, the evaporator superheat, and the heat of compression generated by the compressor. The air stream 53 leaving the condenser coil 62 and the air stream 65 leaving the condenser coil 60 are heated. The refrigerant after dissipating its heat through the condenser coils approaches the metering device 81 where the pressure of the liquid is reduced to a lower evaporator pressure condition. When the liquid is expanded into the evaporator coils 70 and 72 through the output orifice of the metering device 81, the temperature and pressure of the refrigerant liquid is reduced. Although two evaporator coils and one expansion valve is shown in the drawings, it should be understood that more than two coils may be provided and an expansion valve may be installed at each evaporator coil.
The process intake air 30 crosses optional condenser coil 110 which dissipates its heat into the crossing air stream which leaves the condenser in air stream 51 and enters the isolated regeneration zone Z4 of the rotor 9 where the crossing air interchanges its energy with the preconditioned desiccant and exits the rotor as regenerated exhaust air 56 which interchanges its energy through an adiabatic cooling effect and moisture is dissipated into the crossing air 56. The regenerated exhaust air stream 56 then crosses the refrigerant cooling evaporator coil 72 where part of the moisture in the air stream is removed by the evaporator coil which drains into a drain pan and leaves the evaporator coil in air stream 96 which is colder but still somewhat saturated. The colder somewhat saturated air stream 96 then enters isolated desiccant zone Z3 of the rotor which adsorbs the moisture content in an adiabatic constant enthalpy reaction, and the dehumidified and adiabatically reheated air leaves zone Z3 in air stream 111 and crosses the condenser coil 115 which reheats the air stream 120, which is discharged as process delivery or supply air 31.
As mentioned above, the metering device or expansion valve or valves restrict the high-pressure liquid and creates a reverse refrigerant adiabatic effect, after which, the refrigerant is discharged or suctioned to the evaporator coil or evaporator coils 70, 72 at lower refrigerant temperature and pressure conditions, which enable the evaporator coil(s) to absorb heat from the crossing air that is forced through the coil(s) by the evaporator fan. The air exiting the evaporator coil(s) is discharged as cool air and the refrigerant absorption process changes the refrigerant from liquid-gas to gas, which is then suctioned back to the compressor to complete the closed cycle.
Simultaneously as the processes occur in the desiccant rotor zones Z4 and Z3, the processes described above in the first and second closed loops occur in isolated desiccant zones Z2 and Z1. In these zones, the two separate air streams interchange refrigerant energy through the evaporator coil 70 and condenser coil 60 of the refrigeration system, as described above.
The desiccant at zone Z3 has been preconditioned by the process air stream prior to rotation to have a lowered temperature and elevated moisture content. The air 14 leaving the condenser coil 60 flows through the isolated rotor zone Z1, which gradually heats the desiccant. This energy exchange also results in a cooling effect caused, in part, by the heat sink effect and also caused by an adiabatic cooling effect, thereby releasing some moisture in the air stream leaving the isolated desiccant zone Z1. This air enters the intake of the re-circulating fan 11 and the cooled air 13 is discharged to enter the condenser coil 60. As previously mentioned the condenser coil 60 dissipates its refrigerant energy to the crossing air stream 13, thereby heating the air stream 14 leaving the condenser coil. The heated air stream 14 re-enters the isolated desiccant zone Z1 of the rotor 9 in the closed recirculation loop process described above.
In the second closed loop, the zone circulating fan 21 conducts a separate isolated air stream in a flow path 23 across an evaporator coil 70 which cools the air stream, and the cooled air stream 24 crosses the isolated desiccant zone Z2 of the desiccant rotor 9 and returns to the suction side of the zone circulating fan 21 in a continuous closed loop that provides constant heat energy removal to affect the desiccant temperature and vapor conditions. The desiccant in zone Z2 has been preconditioned from the regeneration air stream at Z4 prior to rotation to have an elevated temperature and is substantially dry. The cool air 24 leaving the evaporator coil 70 flows through the isolated rotor zone Z 1, which gradually cools the desiccant material, and the air 22 leaving zone Z2 returns to the suction side of the zone circulating fan 21 in the continuous closed loop process described above.
The transferred and added energy caused by the isolated closed loops and refrigeration energy exchanges results in the transport of sensible energy from the isolated zone Z2 to isolated zone Z1. The closed loops also maximize refrigerant energy and accelerate the vapor differential exiting between both zones Z3 and Z4. As the desiccant is rotated from zone Z1 to zone Z4, the reset of temperature and vapor conditions facilitate preparing it for the next regeneration process.
The heat transfer feature between the zones Z2 and Z1 enables the desiccant and moisture conditions to be reduced in total heat capacitance which diminishes the unwanted re-heat effect of the desiccant when the rotor 9 is rotated from zone Z2 to the process zone Z3. The process intake air 30 flows across the optional evaporator coil 72 absorbs energy through the crossing air stream and the leaving air 96 is cooled before entering zone Z3 as result of the refrigeration evaporating process and facilitates the absorption of moisture as it crosses zone Z3. The air stream leaving zone Z3 and discharged as process delivery or supply air 31 is also diminished in heat due to the heat sink effect from the rotated desiccant zone Z2. These heat transfer process augment the total effective cooling. The air 111 leaving zone Z3 could be re-heated by the second optional condenser coil 115 to re-capture this heat effect, or an additional evaporator may be used to simply cool the leaving delivery or supply air 31.
Although the condenser coil 62 is installed to accommodate condensing energy and diminish the crossing air, other devices may be utilized to bypass the refrigerant so as to enable transfer or re-direct refrigerant energy to any of the other condensing coils 60 and/or 110 and/or 115.
It should be understood, that the refrigeration system that the refrigeration system may be provided without the optional condenser coils 62 and/or 60 and/or 115 and/or 110 and the evaporator coils 72 and/or 70, or may utilize any number of condenser and evaporator coils connected in a series or parallel sequence or combination thereof. It should also be understood that the condenser coils may be combined as one device with a physical air separation and evaporator coils may be combined as one device with a physical air separation. It should also be understood that valves may be provided to control air flow volume and/or to control refrigerant capacity or to direct refrigerant toward alternate condenser coils.
In this modification, the evaporator has two separate coils 72 and 72B and the intake process air 30, which may be any preconditioned air or outside air, may be separated into two air flow paths by damper 101. In a first air stream, a portion of the process intake air 30 enters the isolated regeneration zone Z4 of the rotor 9 in air stream 51 where the crossing air interchanges its energy with the preconditioned desiccant and exits the rotor as regenerated exhaust air 56 which interchanges its energy through an adiabatic cooling effect and moisture is dissipated into the crossing air 56. The regenerated exhaust air stream 56 then crosses the refrigerant cooling evaporator coil 72 where part of the moisture in the air stream is removed by the evaporator coil which drains into a drain pan and leaves the evaporator coil in air stream 96 which is colder but still somewhat saturated. The colder somewhat saturated air stream 96 then enters isolated desiccant zone Z3 of the rotor which adsorbs the moisture content in an adiabatic constant enthalpy reaction, and the dehumidified and adiabatically reheated air leaves zone Z3 in air stream 111 and discharged as process delivery or supply air 31.
In a bypass air stream, a second portion of the process intake air 30 can be directed by the damper 101 across the evaporator coil 72B which leaves the evaporator coil in bypass air stream 102 and bypasses the isolated desiccant zone Z3 of the rotor 9 to rejoin the air stream 111 exiting the desiccant zone Z3 and the mixed air 120 is discharged as process delivery or supply air 31. The optional bypass air path enables selective control of the refrigeration cooling effect cause by the refrigeration process.
Outdoor air 50 in a separate air flow path or bypass system crosses an optional condenser coil 61 and is discharged as discharge air 53, as described in
The air flow paths of the first and second closed loops and the refrigeration coil arrangement in the closed loops are the same as described above with reference to
Although some of the systems described herein utilize refrigerant coils, for purposes of example, it should be understood that other equivalent heating and cooling energy exchange systems and devices may be used, such as a heat pump system and water type heat exchangers.
It should also be understood that the system and processes described herein may also utilize other heat and cooling energy exchange devices to transfer energy into and out of the system, for example, a solar heating closed loop.
It should also be further understood that portions or parts of the systems depicted in some of the drawings can be combined or mixed with portions or parts of the systems shown in other drawings to provide additional processes.
Although, for purposes of example, the invention has been described in various preferred forms, as an air conditioning system for dehumidification, humidification, moisture removal, and capture of moisture, it should be understood that the present invention is not limited to performing only that function. The present desiccant rotor system and process may also be utilized to remove unwanted gases such as carbon dioxide, carbon monoxide, hydrogen, and nitrogen, in the manner of a gas separator, gas accumulator, gas filtering apparatus, or water system accumulator.
While the invention has been disclosed in various preferred forms, the specific embodiments thereof as disclosed and illustrated herein are considered as illustrative only of the principles of the invention and are not to be considered in a limiting sense in interpreting the claims. The claims are intended to include all novel and non-obvious combinations and sub-combinations of the various elements, features, functions, and/or properties disclosed herein.
Variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art from this disclosure, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed in the following claims defining the present invention. Thus, it shall be understood that while this invention has been described with respect to various specific examples and embodiments, the invention is not limited thereto and that it can be variously practiced within the scope of the following claims.
This application claims priority of U.S. Provisional Application Ser. No. 61/005,011, filed Dec. 3, 2007.
| Number | Date | Country | |
|---|---|---|---|
| 61005011 | Dec 2007 | US |
