Heat and mass transfer analysis and performance comparison for different solid dehumidification methods

Three kinds of solid desiccant dehumidifier are compared,which are desiccant wheel dehumidifier,heat pump driven inner-cooling desiccant dehumidifier,and heat pump driven multi-stage desiccant dehumidifier.Mathematical models of desiccant wheel and multi-stage desiccant dehumidifiers are set up and validated by experimental results.The dehumidification performance of the three dehumidifiers shows that the inner cooling desiccant method gives the best heat and mass transfer process,while the desiccant wheel dehumidifier is the worst.Regeneration temperature of desiccant wheel is usually above 80℃,while that of inner cooling desiccant bed and multi-stage desiccant bed are both below 50℃.To obtain the same humidity ratio of the supplied air,air states of desiccant wheel is near isenthalpic line with high supplied air temperature,while the COP of inner cooling desiccant bed and multi-stage desiccant bed is above 4 with low supplied air temperature.