Study On The Performance Of Regenerator For Liquid Desiccant Air Conditioning System

Abstract：With the development and improvement of China’s social economy, science andtechnology, people are eager to pursuit higher quality of life and industrial productioneffects, especially in recent years fog and haze appeared frequently, deterioratingenvironment. Under these conditions, traditional air conditioning systems have been unableto meet this demand, and cause energy waste. Thus, some experts put forward temperatureand humidity independent control air conditioning system. Liquid desiccant is one of themethods for temperature and humidity independent control. Liquid desiccant airconditioning system doesn’t have to freeze the air below the dew point temperature, andcan realize the processing of air at higher temperature. Salt solution with sterilization,disinfection to air, can improve the indoor air quality. However, after the process airdehumidified by salt solution, the concentration and dehumidification capacity of saltsolution decrease. In order to be able to recycle, salt solution has to be regenerated.Regeneration of salt solution can take advantage of high temperature flue gas, solar energyand other low grade waste heat, reducing energy consumption.This paper makes a theoretical study of liquid desiccant air conditioning system inregenerator. By heat and mass transfer analysis, the mathematical model of the regeneratorwas built. Through theoretical calculations, the effects of inlet air and liquid parameters onthe differential between inlet and outlet air humidity ratio and liquid concentration, outletliquid temperature were simulated.In this paper, the regenerator was a counter-current packed tower form, using LiClliquid as the regeneration liquid. Through orthogonal experiment design, experimental datawere analyzed by the method of range and variance. Significant factors and significancelevel affecting the performances of regeneration, outlet liquid temperature were drawn inthis experiment. And finally, the experimental results were compared with the numericalsimulation results of which errors were analyzed.Through theoretical and experimental analysis, conclusions are as follows:(1) Air regeneration capacity increased with the increasing of inlet liquid temperature,liquid to air ratio, and decreased with the increasing of inlet liquid concentration and inletair humidity ratio; along with the change of inlet air temperature was more gentle;(2) Inlet liquid temperature was the main factor affecting the air regeneration quantity.In the future experiment extra attention should be paid. The effect of inlet air temperatureon regeneration was weak.(3) Inlet liquid temperature and liquid-air ratio were the main factors affecting theoutlet liquid temperature. (4) Under these experimental conditions, the optimal scheme combination of the airregeneration experiment was: inlet liquid temperature was76℃, the inlet liquidconcentration was30%, liquid to air ratio was2.5, inlet air temperature and humidity ratiowere36℃and12g/kg, respectively.(5) Selecting a group of experimental conditions, the regeneration capacity was17.61g/kg, the energy efficiency was79.76%.