Liquid desiccant air-conditioning systems and methods for greenhouses and growth cells

Abstract

This application relates generally to liquid desiccant air conditioning (LDAC) systems and, more specifically, to liquid desiccant air-conditioning systems for use in greenhouses and growth cells.

1 . A liquid desiccant air-conditioning system for managing temperature and humidity conditions in a greenhouse or a growth cell, comprising:
 a liquid desiccant conditioner utilizing a liquid desiccant to dehumidify a first air stream flowing therethrough, said first air stream entering the liquid desiccant conditioner from a space within the greenhouse or growth cell and exiting the liquid desiccant conditioner as supply air to the greenhouse or growth cell;   a liquid desiccant regenerator receiving the liquid desiccant used in the liquid desiccant conditioner, and humidifying a second air stream flowing therethrough to concentrate the liquid desiccant and then returning the liquid desiccant to the conditioner; and   an air-to-air heat exchanger thermally coupled to the air stream exiting the liquid desiccant conditioner or an air stream drawn from the space within the greenhouse or growth cell and the second air stream exiting the liquid desiccant regenerator for cooling the second air stream and producing water therefrom;   wherein the second air stream circulates between the liquid desiccant regenerator and the air-to-air heat exchanger within a closed enclosure.   
     
     
         2 . The system of  claim 1 , further comprising a heat source for heating the liquid desiccant regenerator and a cold source for cooling the liquid desiccant conditioner. 
     
     
         3 . The system of  claim 2 , wherein the heat source comprises a power generator. 
     
     
         4 . The system of  claim 3 , wherein the power generator supplies carbon dioxide to the greenhouse or growth cell. 
     
     
         5 . The system of  claim 1 , further comprising a chiller system for heating the liquid desiccant regenerator and cooling the liquid desiccant conditioner. 
     
     
         6 . The system of  claim 1 , wherein the water is used to water soil in the greenhouse or growth cell. 
     
     
         7 . The system of  claim 1 , wherein the water drives a cooling tower that provides cooling water to the liquid desiccant conditioner. 
     
     
         8 . The system of  claim 7 , further comprising a chiller for controlling temperature of the cooling water provided to the liquid desiccant conditioner. 
     
     
         9 . A method of managing temperature and humidity conditions in a greenhouse or a growth cell using a liquid desiccant air conditioning system, comprising:
 dehumidifying a first air stream flowing through a liquid desiccant conditioner utilizing a liquid desiccant, said first air stream being drawn into the liquid desiccant conditioner from a space within the greenhouse or growth cell and exiting the liquid desiccant conditioner as supply air to the greenhouse or growth cell;   receiving, in a liquid desiccant regenerator, the liquid desiccant used in the liquid desiccant conditioner, and humidifying a second air stream flowing through the liquid desiccant regenerator to concentrate the liquid desiccant and then returning the liquid desiccant to the conditioner; and   cooling the second air stream humidified by the liquid desiccant regenerator and producing water therefrom using an air-to-air heat exchanger thermally coupled to the air stream exiting the liquid desiccant conditioner or an air stream drawn from the space within the greenhouse or growth cell; and   circulating the second air stream between the liquid desiccant regenerator and the air-to-air heat exchanger within a closed enclosure.   
     
     
         10 . The method of  claim 9 , further comprising heating the liquid desiccant regenerator and cooling the liquid desiccant conditioner. 
     
     
         11 . The method of  claim 10 , wherein heating is performed utilizing heat from a power generator. 
     
     
         12 . The method of  claim 11 , wherein the power generator supplies carbon dioxide to the greenhouse or growth cell. 
     
     
         13 . The method of  claim 9 , further comprising using the water to water soil in the greenhouse or growth cell. 
     
     
         14 . The method of  claim 9 , further comprising providing the water to a cooling tower that provides cooling water to the liquid desiccant conditioner. 
     
     
         15 . The method of  claim 14 , further comprising controlling temperature of the cooling water provided to the liquid desiccant conditioner using a chiller. 
     
     
         16 . A method of managing temperature and humidity conditions in a greenhouse or a growth cell using a liquid desiccant air conditioning system, comprising:
 (a) dehumidifying, using a liquid desiccant, a first air stream drawn from a space within the greenhouse or growth cell to be provided as supply air to the greenhouse or growth cell;   (b) concentrating the liquid desiccant used in (a) by humidifying a second air stream;   (c) cooling the second air stream to produce water therefrom using the first air stream or an air stream received from the space within the greenhouse or growth cell; and   (d) circulating the second air stream in a closed enclosure for repeating (b) and (c).   
     
     
         17 . A liquid desiccant air-conditioning system for managing temperature and humidity conditions in a greenhouse or a growth cell, comprising:
 a liquid desiccant conditioner utilizing a liquid desiccant to dehumidify a first air stream flowing therethrough to be provided as supply air to the greenhouse or growth cell, said first air stream entering the liquid desiccant conditioner from a space within the greenhouse or growth cell;   a liquid desiccant regenerator receiving the liquid desiccant used in the liquid desiccant conditioner, and utilizing a second air stream flowing therethrough to concentrate the liquid desiccant, and then returning the liquid desiccant to the conditioner, wherein the liquid desiccant regenerator heats and humidifies the second air stream, said second air stream entering the liquid desiccant regenerator from outside the greenhouse or growth cell and exiting the liquid desiccant regenerator to be exhausted outside the greenhouse or growth cell;   an air-to-air heat exchanger thermally coupled to the first air stream exiting the liquid desiccant conditioner and the second air stream exiting the liquid desiccant regenerator for heating the first air stream before the first air stream is provided as the supply air to the greenhouse or growth cell and the second air stream is exhausted from the greenhouse or growth cell.   
     
     
         18 . The system of  claim 17 , further comprising a heat source for heating the liquid desiccant regenerator and a cold source for cooling the liquid desiccant conditioner. 
     
     
         19 . The system of  claim 18 , wherein the heat source comprises a power generator. 
     
     
         20 . The system of  claim 19 , wherein the power generator supplies carbon dioxide to the greenhouse or growth cell. 
     
     
         21 . The system of  claim 17 , further comprising a chiller system for heating the liquid desiccant regenerator and cooling the liquid desiccant conditioner. 
     
     
         22 . A liquid desiccant air-conditioning system for managing temperature and humidity conditions in a greenhouse or a growth cell, comprising:
 a liquid desiccant conditioner utilizing a liquid desiccant to dehumidify a first air stream flowing therethrough to be provided as supply air to the greenhouse or growth cell, said first air stream entering the liquid desiccant conditioner from a space within the greenhouse or growth cell;   a liquid desiccant regenerator receiving the liquid desiccant used in the liquid desiccant conditioner, and utilizing a second air stream flowing therethrough to concentrate the liquid desiccant, and then returning the liquid desiccant to the conditioner, wherein the liquid desiccant regenerator heats and humidifies the second air stream, said second air stream provided to the liquid desiccant regenerator from outside the greenhouse or growth cell and exiting the liquid desiccant regenerator to be exhausted outside the greenhouse or growth cell;   an air-to-air heat exchanger thermally coupled to the second air stream prior to entering the liquid desiccant regenerator and the second air stream exiting the liquid desiccant regenerator for preheating the second air stream entering the liquid desiccant regenerator and post cooling the second air stream exiting the liquid desiccant regenerator.   
     
     
         23 . The system of  claim 22 , further comprising a heat source for heating the liquid desiccant regenerator and a cold source for cooling the liquid desiccant conditioner. 
     
     
         24 . The system of  claim 23 , wherein the heat source comprises a power generator. 
     
     
         25 . The system of  claim 24 , wherein the power generator supplies carbon dioxide to the greenhouse or growth cell. 
     
     
         26 . The system of  claim 22 , further comprising a chiller system for heating the liquid desiccant regenerator and cooling the liquid desiccant conditioner. 
     
     
         27 . A liquid desiccant air-conditioning system for managing temperature and humidity conditions in a greenhouse or a growth cell, comprising:
 a liquid desiccant conditioner utilizing a liquid desiccant to dehumidify a first air stream flowing therethrough to be provided as supply air to the greenhouse or growth cell, said first air stream entering the liquid desiccant conditioner from a space within the greenhouse or growth cell;   a liquid desiccant regenerator receiving the liquid desiccant used in the liquid desiccant conditioner, and utilizing a second air stream flowing therethrough to concentrate the liquid desiccant, and then returning the liquid desiccant to the conditioner, wherein the liquid desiccant regenerator heats and humidifies the second air stream, said second air stream provided to the liquid desiccant regenerator from outside the greenhouse or growth cell and exiting the liquid desiccant regenerator to be exhausted outside the greenhouse or growth cell;   an air-to-air heat exchanger thermally coupled to the first air stream prior to entering the liquid desiccant conditioner and the first air stream exiting the liquid desiccant conditioner for precooling the first air stream entering the liquid desiccant conditioner and post heating the first air stream exiting the liquid desiccant conditioner.   
     
     
         28 . The system of  claim 27 , further comprising a heat source for heating the liquid desiccant regenerator and a cold source for cooling the liquid desiccant conditioner. 
     
     
         29 . The system of  claim 28 , wherein the heat source comprises a power generator. 
     
     
         30 . The system of  claim 29 , wherein the power generator supplies carbon dioxide to the greenhouse or growth cell. 
     
     
         31 . The system of  claim 27 , further comprising a chiller system for heating the liquid desiccant regenerator and cooling the liquid desiccant conditioner.