Evaporative cooling system with liquid-to-air membrane energy exchanger

Abstract

An evaporative cooling system includes an evaporative cooler liquid-to-air membrane energy exchanger (LAMEE), a first liquid-to-air heat exchanger (LAHE), and a cooling fluid circuit. The evaporative cooler LAMEE is disposed within a scavenger air plenum that is configured to channel a scavenger air stream. The first LAHE is disposed within a process air plenum that is configured to channel a process air stream. The cooling fluid circuit is configured to circulate an evaporative cooling fluid between the evaporative cooler LAMEE and the first LAHE. The evaporative cooler LAMEE is configured to utilize the scavenger air stream to evaporatively cool the cooling fluid. The first LAHE is configured to receive the cooling fluid from the evaporative cooler LAMEE and to allow the cooling fluid to absorb heat from the process air stream to cool the process air stream.

1 .- 30 . (canceled) 
     
     
         31 . An evaporative cooling system comprising:
 an evaporative cooler liquid-to-air membrane energy exchanger (LAMEE) disposed within a scavenger air plenum that is configured to channel a scavenger air stream, the evaporative cooler LAMEE comprising one or more semi-permeable membranes and being configured to direct water and the scavenger air stream through one or more separate channels divided by the one or more semi-permeable membranes, the evaporative cooler LAMEE being configured to exchange latent and sensible energy between the scavenger air stream and the water without exchanging energy between the scavenger air stream and any other liquid;   a first liquid-to-air heat exchanger (LAHE) disposed within a process air plenum that is configured to channel a process air stream; and   a closed cooling liquid circuit that is configured to circulate the water between the evaporative cooler LAMEE and the first LAHE, wherein the evaporative cooler LAMEE is configured to utilize the scavenger air stream to evaporatively cool the water, and wherein the first LAHE is configured to receive the water from the evaporative cooler LAMEE and to allow the water to absorb heat from and cool the process air stream.   
     
     
         32 . The evaporative cooling system of claim  1 , wherein the first LAHE is configured to discharge the process air stream as conditioned supply air that is directed to the enclosed space. 
     
     
         33 . The evaporative cooling system of claim  1 , further comprising a second LAHE disposed within the scavenger air plenum upstream of the evaporative cooler LAMEE in a direction of flow of the scavenger air stream, the second LAHE configured to receive the water from at least one of the evaporative cooler LAMEE or the first LAHE and to allow heat transfer between the water and the scavenger air stream upstream of the evaporative cooler LAMEE. 
     
     
         34 . The evaporative cooling system of claim  3 , wherein the cooling fluid circuit is configured to divide the water exiting the evaporative cooler LAMEE between a first pathway that directs a first stream of the water to the first LAHE and a second pathway that directs a second stream of the water to the second LAHE. 
     
     
         35 . The evaporative cooling system of claim  1 , wherein the first LAHE is a second evaporative cooler LAMEE. 
     
     
         36 . The evaporative cooling system of claim  1 , further comprising a chiller disposed along the cooling liquid circuit between the evaporative cooler LAMEE and the first LAHE, the chiller selectively operable to provide additional cooling of the water prior to entering the first LAHE when the chiller is operating. 
     
     
         37 . The evaporative cooling system of claim  1 , further comprising a dehumidification LAMEE disposed in the scavenger air plenum upstream of the evaporative cooler LAMEE in a direction of flow of the scavenger air stream and configured to circulate a liquid desiccant to reduce at least one of humidity or temperature of the scavenger air. 
     
     
         38 . The evaporative cooling system of claim  7 , wherein the dehumidification LAMEE is configured to discharge the liquid desiccant to a liquid-to-liquid heat exchanger (LLHE) that is coupled to the cooling fluid circuit, the LLHE configured to allow heat transfer from the liquid desiccant to the water of the cooling fluid circuit prior to the water entering the evaporative cooler LAMEE. 
     
     
         39 . The evaporative cooling system of claim  7 , further comprising a regeneration system coupled to the dehumidification LAMEE via a desiccant line, the regeneration system configured to receive the liquid desiccant via the desiccant line and to remove moisture from the liquid desiccant by at least one of heating, filtering, membrane distillation, or a vacuum process to increase a concentration of the liquid desiccant. 
     
     
         40 . The evaporative cooling system of claim  1 , further comprising an air-to-air heat exchanger (AAHE) disposed within the scavenger air plenum downstream of the evaporative cooler LAMEE in a direction of flow of the scavenger air stream and within the process air plenum upstream of the first LAHE in a direction of flow of the process air stream, the AAHE configured to receive both the scavenger air stream and the process air stream and to allow the scavenger air stream to absorb heat from the process air stream prior to the process air stream entering the first LAHE. 
     
     
         41 . The evaporative cooling system of claim  10 , wherein a downstream portion of the scavenger air plenum downstream of the evaporative cooler LAMEE in the direction of flow of the scavenger air is at least one of curved or angled to be at least proximate to an upstream portion of the scavenger air plenum upstream of the evaporative cooler LAMEE, the AAHE disposed within the downstream portion of the scavenger air plenum and the upstream portion of the scavenger air plenum to allow the scavenger air exhaust stream to absorb heat from the scavenger air supply stream prior to the scavenger air supply stream entering the evaporative cooler LAMEE. 
     
     
         42 . The evaporative cooling system of claim  10 , wherein the AAHE extends across the evaporative cooler LAMEE from a back of the evaporative cooler LAMEE to a front of the evaporative cooler LAMEE, the AAHE configured to absorb heat from the scavenger air supply stream prior to the scavenger air supply stream entering the evaporative cooler LAMEE through the air inlet. 
     
     
         43 . A method comprising:
 channeling a scavenger air stream through an evaporative cooler liquid-to-air membrane energy exchanger (LAMEE) that is disposed within a scavenger air plenum, the evaporative cooler LAMEE comprising one or more semi-permeable membranes and being configured to direct water and the scavenger air stream through one or more separate channels divided by the one or more semi-permeable membranes, the evaporative cooler LAMEE being configured to exchange latent and sensible energy between the scavenger air stream and the water without exchanging energy between the scavenger air stream and any other liquid;   channeling a process air stream through a first liquid-to-air heat exchanger (LAHE) that is disposed within a process air plenum;   circulating the water between the evaporative cooler LAMEE and the first LAHE through a closed cooling liquid circuit;   evaporatively cooling the water within the evaporative cooler LAMEE utilizing the scavenger air stream; and   receiving the cooled water at the first LAHE from the evaporative cooler LAMEE, wherein the receiving operation includes allowing the cooled water to absorb heat from the process air stream to cool the process air stream.