Abstract:
An air temperature control unit comprising a refrigeration circuit ( 10, 6, 7, 7   a   , 12, 13, 14 ), a warm air chamber ( 4 ) housing a condenser ( 7 ) and a cool air chamber ( 5 ) housing an evaporator ( 10 ); wherein a water holding tank ( 24 ) is in fluid communication with the evaporator for collecting condensed water and a water pump ( 20 ) communicates the condensed water from the water holding tank ( 24 ) through a water purifying system ( 21, 22 ) to a water outlet device ( 23 ). A mixture of cooled air from the cool air chamber ( 5 ) and warm air from the warm air chamber ( 4 ) is used to maintain a predetermined inside temperature while excess cool air and warm air is exhausted to the outdoor environment. The system can therefore operate continuously to supply purified water without stopping the unit due to warm and cooled air being continually mixed to maintain the predetermined inside temperature, while excess warm and cooled air is exhausted to the outside environment.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure is directed at an air temperature control unit and process for controlling air temperature and producing purified water. 
       BACKGROUND 
       [0002]    Air conditioning units use a refrigeration cycle with four essential elements to cool an indoor area. The system refrigerant starts its cycle in a gaseous state. A compressor pumps the refrigerant gas up to a high pressure and temperature. From there refrigerant gas enters a heat exchanger (sometimes called a “condensing coil” or condenser) where it loses energy (heat) to the outside, cools, and condenses into its liquid phase. The liquid refrigerant passes through another heat exchanger where the liquid refrigerant evaporates, hence the heat exchanger is often called an “evaporating coil” or evaporator. Warm indoor air is drawn over the surface of the evaporator by a fan. As the liquid refrigerant evaporates to gas it absorbs energy (heat) from the warm air passing over the evaporator and cool air is exhausted from the air conditioning unit thereby cooling the surrounding indoor area. The warm refrigerant gas returns to the compressor, and the cycle is repeated. In the process, heat is absorbed from indoor air and transferred outdoors, resulting in cooling of the building or vehicle. 
         [0003]    The heat created by the condenser in the cooling process is discharged outdoors in the form of waste heat. There is a significant temperature difference between the indoor air surrounding the air conditioning unit and the air immediately surrounding the compressor and condenser of the unit. A great deal of waste heat is created through the efforts of cooling air. Water is also generation through the air cooling process as the warm indoor air contacts the cool surface of the evaporator creating a dew point. Water vapour in the warm air condenses on the evaporator as the air is cooled thereby dehumidifying the air. The water generated through the process is generally collected and discharged into the environment through the use of drains. 
         [0004]    Various conventional systems for extracting drinking water from the air are available. These systems generally use an apparatus that enables the condensation process to occur, thereby producing a condensate that is harvested as pure drinking water. An air conditioner system naturally produces a condensate as it cools air. There are known systems for extracting water produced by air conditioning units, and these systems may further include a water treatment or water purification step to produce water meeting world health organization standards for drinking. The process of extracting drinking water from the air is advantageous since it eliminates the need for access to groundwater or seawater and the ambient air is a sustainable and accessible resource. 
       SUMMARY 
       [0005]    According to a first aspect, there is provided an air temperature control unit comprising: a housing defining a warm air chamber and a cool air chamber; a refrigerant circuit for circulating a refrigerant, the refrigerant circuit comprising a refrigerant pump, a plurality of conduits, a compressor, a condenser, an expansion device and an evaporator comprising a plurality of evaporator coils, wherein the condenser is housed in the warm air chamber and the evaporator is housed in the cool air chamber, and the plurality of conduits fluidly connect the compressor, the condenser, the expansion device and the evaporator; a drive motor coupled with the compressor for driving the compressor; a fan in the cool air chamber for drawing ambient air from outside the housing across the plurality of evaporator coils to cool the ambient air and condense water vapor from the ambient air on an external surface of the evaporator coils; a water holding tank in fluid communication with the evaporator for collecting the condensed water; a water purifying system in fluid communication with the water holding tank for purifying the condensed water; a water outlet device in fluid communication with the water purifying system for controllably dispensing the purified water; a water pump for pumping the condensed water from the water holding tank through the water purifying system to the water outlet device; a duct system comprising a cool air duct in fluid communication with the cool air chamber and a warm air duct in fluid communication with the warm air chamber for respectively receiving the cooled ambient air from the cool air chamber and warm air from the warm air chamber; an indoor air outlet fluidly coupled with the duct system for exhausting air into an indoor environment surrounding the air temperature control unit; thermostatic controls communicative with the duct system configured to control an amount of the warm air and an amount of the cooled ambient air exhausted into the indoor environment via the indoor air outlet to achieve an indoor air temperature within a predetermined temperature range; and an outdoor air outlet fluidly coupled with the duct system for exhausting excess warm air and excess cooled ambient air into an outdoor environment external to the indoor environment, wherein the excess warm air and the excess cooled ambient air comprise the warm air and the cooled ambient air not exhausted into the indoor environment via the indoor air outlet. 
         [0006]    The duct system may further comprise a blending duct fluidly coupled with the cool air duct, the warm air duct and the indoor air outlet. The thermostatic controls may be configured to control the amount of the cooled ambient air from the cool air duct flowing into the blending duct and the amount of the warm air from the warm air duct flowing into the blending duct to form a blended air and the blended air may be exhausted into the indoor environment via the indoor air outlet to achieve the indoor air temperature within the predetermined temperature range. 
         [0007]    The thermostatic controls may comprise: at least one temperature sensor positioned in the blending duct; an adjustable warm air baffle in fluid communication with the warm air duct; an adjustable cool air baffle in fluid communication with the cool air duct; and a controller communicative with the temperature sensor, the warm air baffle and the cool air baffle and configured to receive temperature measurements from the temperature sensor and adjust the warm air baffle and the cool air baffle to control the amounts of the warm air and the cooled ambient air flowing into the blending duct to form the blended air. 
         [0008]    The unit may further comprise at least one fan positioned in the warm air chamber for circulating the warm air around the warm air chamber. The water holding tank may be positioned below the cool air chamber such that the condensed water drains under gravity into the water holding tank. The water purifying system may be housed in the cool air chamber. The evaporator coils may be coated with a ceramic. The ceramic may comprise porcelain. At least one of the compressor, the expansion device or the drive motor may be housed in the warm air chamber. The compressor, the expansion device and the drive motor may be housed in the warm air chamber. 
         [0009]    According to another aspect, there is provided a method for maintaining air temperature in an indoor environment within a predetermined temperature range and producing purified drinking water. The method comprises: providing an air temperature control unit in the indoor environment. The air temperature control unit comprises: a housing defining a warm air chamber and a cool air chamber; a refrigerant circuit comprising a refrigerant pump, a plurality of conduits, a compressor, a condenser, an expansion device and an evaporator comprising a plurality of evaporator coils, wherein the condenser is housed in the warm air chamber and the evaporator is housed in the cool air chamber, and the plurality of conduits fluidly connect the compressor, the condenser, the expansion device and the evaporator; a drive motor coupled with the compressor; a fan in the cool air chamber; a water holding tank in fluid communication with the evaporator; a water purifying system in fluid communication with the water holding tank; a water outlet device in fluid communication with the water purifying system; a water pump; a duct system comprising a cool air duct in fluid communication with the cool air chamber and a warm air duct in fluid communication with the warm air chamber; thermostatic controls communicative with the duct system; an indoor air outlet fluidly coupled with the duct system; and an outdoor air outlet fluidly coupled with the duct system. The method further comprises: actuating the refrigerant pump to continuously circulate refrigerant around the refrigerant circuit and actuating the fan to draw ambient air from outside the housing across the plurality of evaporator coils, wherein liquid refrigerant flows through the evaporator coils and evaporates to refrigerant gas thereby cooling the ambient air and condensing water vapor from the ambient air on an external surface of the evaporator coils; the refrigerant gas flows to the compressor and is compressed; the compressed refrigerant gas flows to the condenser and is condensed to form the liquid refrigerant thereby transferring the heat of condensation to air surrounding the condenser to produce warm air in the warm air chamber; and the liquid refrigerant is expanded in the expansion device before the liquid refrigerant enters the evaporator; flowing the cooled ambient air from the cool air chamber into the cool air duct and flowing the warm air from the warm air chamber into the warm air duct; actuating the thermostatic controls to control an amount of the warm air and an amount of the cooled ambient air exhausted into the indoor environment via the indoor air outlet to achieve an indoor air temperature within a predetermined temperature range; exhausting excess warm air and excess cooled ambient air into an outdoor environment external to the indoor environment via the outdoor air outlet, wherein the excess warm air and the excess cooled ambient air comprise the warm air and the cooled ambient air not exhausted into the indoor environment via the indoor air outlet; and actuating the water pump to pump the condensed water collected in the water holding tank through the water purifying system to the water outlet device, whereby purified drinking water can be controllable dispensed from the water outlet device on demand. 
         [0010]    The duct system may further comprises a blending duct fluidly coupled with the cool air duct, the warm air duct and the indoor air outlet. The thermostatic controls may be actuated to control the amount of the cooled ambient air from the cool air duct flowing into the blending duct and the amount of the warm air from the warm air duct flowing into the blending duct to form a blended air and the blended air may be exhausted into the indoor environment via the indoor air outlet to achieve the indoor air temperature within the predetermined temperature range. 
         [0011]    The thermostatic controls may comprise: at least one temperature sensor positioned in the blending duct; an adjustable warm air baffle in fluid communication with the warm air duct; an adjustable cool air baffle in fluid communication with the cool air duct; and a controller communicative with the temperature sensor, the warm air baffle and the cool air baffle. The controller may receive temperature measurements from the temperature sensor and adjusts the warm air baffle and the cool air baffle to control the amounts of the warm air and the cooled ambient air flowing into the blending duct to form the blended air. 
         [0012]    The unit may further comprise at least one fan positioned in the warm air chamber and the warm air may be circulated around the warm air chamber by the fan. The water holding tank may be positioned below the cool air chamber and the condensed water may drain under gravity into the water holding tank. The water purifying system may be housed in the cool air chamber. The evaporator coils may be coated with a ceramic. The ceramic may comprise porcelain. At least one of the compressor, the expansion device or the drive motor may be housed in the warm air chamber. The compressor, the expansion device and the drive motor may be housed in the warm air chamber. 
         [0013]    This summary does not necessarily describe the entire scope of all aspects. Other aspects, features and advantages will be apparent to those of ordinary skill in the art upon review of the following description of specific embodiments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    In the accompanying drawings, which illustrate one or more exemplary embodiments: 
           [0015]      FIG. 1  is a schematic view of an air temperature control unit according to an embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    Directional terms such as “top”, “bottom”, “upwards”, “downwards”, “vertically” and “laterally” are used in the following description for the purpose of providing relative reference only, and are not intended to suggest any limitations on how any article is to be positioned during use, or to be mounted in an assembly or relative to an environment. 
         [0017]    The embodiments described herein relate to an air temperature control unit and process for controlling air temperature and producing purified water. The unit utilizes waste heat and water produced in the process of cooling air to control the air temperature of an indoor environment as well as producing purified drinking water. 
         [0018]    Referring to  FIG. 1 , there is shown an air temperature control unit  1  according to an embodiment which incorporates a refrigerant circuit. The air temperature control unit  1  comprises a housing  2  defining a warm air chamber  4  and a cool air chamber  5  with a wall  3  in-between. Warm air chamber  4  includes a compressor  6 , a condenser  7 , and an expansion device  7   a  of the refrigerant circuit as well as a drive motor  8  which drives the compressor  6 . Fans  9  positioned in the warm air chamber  4  circulate air around the chamber  4  and may reduce the likelihood of the drive motor  8  and compressor  6  overheating. The cool air chamber  5  includes an evaporator  10  of the refrigerant circuit and a fan  11 . The evaporator  10  comprises a series of evaporator coils  15  and the fan  11  draws warm ambient air surrounding the unit  1  over and through the coils  15  thereby cooling the air as is explained in more detail below. A liquid refrigerant input conduit  12  fluidly connects the condenser  7  with the evaporator  10  and passes from the warm air chamber  4  to the cool air chamber  5  for flow of liquid refrigerant from the condenser  7  into the evaporator  10 . A refrigerant gas return conduit  13  fluidly connects the evaporator  10  with the compressor  6  and passes from the cool air chamber  5  to the warm air chamber  4  for flow of refrigerant gas from the evaporator  10  to the compressor  6 . A compressed refrigerant gas conduit  14  in the warm air chamber  4  fluidly connects the compressor  6  with the condenser  7  for flow of compressed refrigerant gas from the compressor  6  to the condenser  7 . 
         [0019]    When the air temperature control unit  1  is turned on a refrigerant pump (not shown) pumps refrigerant continuously around the closed refrigerant circuit comprising the evaporator  10 , compressor  6 , condenser  7 , and expansion device  7   a,  which are fluidly connected by the refrigerant conduits  12 ,  13 ,  14 . More specifically, cool low pressure liquid refrigerant enters the evaporator  10  from the liquid refrigerant input conduit  12  and flows inside the evaporator coils  15 . The liquid refrigerant evaporates to gas and cools the ambient air being drawn over and through the evaporator coils  15  by fan  11 . As the ambient air cools a dew point is established and water vapour condenses on the external surface of the evaporator coils  15 . As the water vapour condenses, the latent heat of condensation is transferred to the refrigerant gas inside the evaporator coils  15  and the refrigerant gas is heated. The cooled ambient air collects in the cool air chamber  5  and the low pressure warm refrigerant gas flows from the evaporator  10  along the refrigerant gas return conduit  13  to the compressor  6 . In the compressor  6  the refrigerant gas is compressed to a sufficient pressure that will enable condensation of the high pressure refrigerant gas in the condenser  7 . The compressed refrigerant gas has an elevated pressure and temperature and flows along the compressed refrigerant gas conduit  14  into the condenser  7 . In the condenser  7  heat is transferred from the compressed refrigerant gas to air surrounding the condenser  7  to produce warm air and the compressed refrigerant gas condenses to liquid and is cooled. The cool liquid refrigerant passes from the condenser  7  into the expansion device  7   a  where the cool liquid refrigerant is expanded to reduce the pressure of the liquid refrigerant before it enters the evaporator  10 . 
         [0020]    The end products are cool air collected in the cool air chamber  5 , warm air collected in the warm air chamber  4 , and water droplets that have formed on the surface of the evaporator coils  15 . The cool air in cool air chamber  5  is generally at a temperature of about 56 to 63 degrees Fahrenheit (about 13 to 17 degrees Celsius). The warm air in the warm air chamber  4  is generally at a temperature of about 70 to 80 degrees Fahrenheit (about 21 to 27 degrees Celsius). The water droplets drain under gravity from the evaporator  10  into a water holding tank  24  positioned below and in fluid communication with the evaporator  10 . The cool air chamber  5  includes a water pump  20  which pumps water from the water holding tank  24  to an ultra violet (UV) unit  21  and filtration system  22  positioned in the cool air chamber  5 . The UV unit  21  and filtration system  22  purify the water, and purified water suitable for drinking is dispensed by a tap  23  or other controllable water outlet device fluidly connected to the UV unit  21  and filtration system  22 . Suitable filtration systems  22  include precarbon, sediment, postcarbon, ultrafine or other water purification systems known in the art. Provision of the UV unit  21  and filtration system  22  inside the cool air chamber  5  may beneficially cool the water before it is discharged by tap  23 . In alternative embodiments however, the water purification components may be outside the cool air chamber  5 . The metal evaporator coils  15  may be coated with a non-toxic ceramic material such as a food grade porcelain that allows heat to be transferred from the air to the refrigerant inside the coils  15  whilst preventing or reducing metal contamination of water droplets condensing on the surface of the coils  15 . The coils  15  may be coated with a ceramic coating and baked prior to assembly into the air temperature control unit  1 . 
         [0021]    The air temperature control unit  1  includes a duct system including a cool air duct  31  fluidly connected with the cool air chamber  5  and a warm air duct  30  fluidly connected with the warm air chamber  4 . In one embodiment, the cool air duct  31  and warm air duct  30  are both fluidly connected with a blending duct (not shown) which receives cool air from the cool air duct  31  and warm air from the warm air duct  30 . Thermostatic controls (not shown) sense the air temperature in the blending duct and control the amount of warm air and cool air being mixed in the blending duct to achieve a blended air at a predetermined or preset temperature or within a predetermined or preset temperature range. Thermostatic controls or thermostats are known in the art and readily available. The thermostatic controls may include: one or more temperature sensors (not shown) positioned in or near the blending duct which measure the temperature of the blended air in the blending duct; adjustable air baffles (not shown) in the duct system which can be opened and closed to adjust air flow through the blending duct; and a controller  32  in the warm air chamber  4  communicative with the temperature sensors and adjustable baffles. At least one cool air baffle is in fluid communication with the cool air duct  31  and at least one warm air baffle is in fluid communication with the warm air duct  30  and the baffles control the amount of warm air and cool air flowing into the blending duct. The controller  32  receives measurements from the temperature sensor(s), processes this information and sends signals to the baffles to control the amount of warm air and cool air passing through the baffles to achieve a blended air in the blending duct at a predetermined or preset temperature or within a predetermined or preset temperature range programmed into the controller. Other thermostatic controls as are known in the art may be utilized to control the amount of warm air and cool air being mixed to form the blended air in the blending duct. Furthermore, other controllable air vents or valves may be used as are known in the art instead of the air baffles. The blended air is exhausted from the blending duct via an indoor air outlet into the indoor area surrounding the air temperature control unit  1  so that the surrounding indoor area air temperature is maintained within a desired temperature range. A fan (not shown) may be positioned at or near the indoor air outlet to help circulate the exhausted blended air around the indoor area. 
         [0022]    In an alternative embodiment, the blending duct may not be present and the temperature sensors of the thermostatic controls may be positioned to measure the air temperature of the indoor area surrounding the air temperature control unit  1 . In this alternative embodiment, the thermostatic controls control how much cool air is exhausted into the indoor environment directly from the cool air duct  31  and how much warm air is exhausted into the indoor environment directly from the warm air duct  30  to maintain the indoor air temperature at a predetermined or preset temperature or within a predetermined or preset temperature range. Air baffles or other controllable air vents or valves may be used to control the amount of cool air and warm air being exhausted from the cool air duct  31  and warm air duct  30  into the indoor environment. 
         [0023]    Any excess warm air or excess cool air not blended to form the blended air in the blended duct, or not exhausted directly into the indoor environment to maintain the indoor area temperature within a desired temperature range, is exhausted to the outside environment via an outdoor air outlet fluidly coupled with the duct system. The waste heat produced by the compressor  6 , drive motor  8  and the condenser  7  in the warm air chamber  4  is therefore used to control the temperature of the indoor environment by controllably mixing warm air exhausted from the warm air chamber  4  with cool air exhausted from the cool air chamber  5 . There is no need for the refrigerant circuit of the air temperature control unit  1  to be powered on and off in order to maintain the indoor area at a comfortable temperature. As the air temperature control unit  1  can be continuously run whilst maintaining the indoor temperature within a comfortable temperature range, purified water can be continuously generated which may be beneficial in remote areas without a fresh water supply. Furthermore, the air temperature control unit  1  may be used in colder climates where it is desirable to produce fresh drinking water whilst warming the indoor environment. In colder climates more of the warm air may be blended with the cool air than in warmer climates and the blended air mix can be controlled to provide a comfortable preset or predetermined indoor temperature in both cool or warm climates. By indoor it is meant the inside of a building or vehicle or the like in which the air temperature control unit is positioned. 
         [0024]    The compressor  6  may be a mechanical drive compressor, which are commonly referred to as corkscrew or screw type compressors. Such compressors are well know in the art and are typically run off an internal combustion engine, either using regular gasoline or diesel, rather than electricity. The mechanical drive compressor  6  can be run off an auxiliary engine of a vehicle such as an aeroplane, boat, or larger military or recreational land vehicle. The air temperature control unit  1  can therefore be used in these types of vehicles to provide temperature control inside the vehicle as well as to produce drinking water which is useful when the vehicles are a long way from an available drinking water source. 
         [0025]    While particular embodiments have been described in the foregoing, it is to be understood that other embodiments are possible and are intended to be included herein. It will be clear to any person skilled in the art that modifications of and adjustments to the foregoing embodiments, not shown, are possible.