Performance Evaluation of a Desiccant Dehumidifier using Different Desiccants

  • Prachi Rai Department of Mechanical Engineering IIT (BHU) Varanasi, India
  • S.K. Shukla Mechanical Engineering Department, Indian Institute of Technology (BHU), Varanasi, India.
Keywords: Dehumidifier, Hybrid desiccant cooling system, Lithium chloride and Calcium chloride, Cascade ring, Random packing


This article reports an analysis of different empirical dehumidification effectiveness correlations for packed bed columns using two desiccant solutions viz. lithium chloride and calcium chloride. The analysis shows wide variations in effectiveness values ranging from 10% to 50% or more, with higher deviations occurring for lower ratios of liquid to gas flow rates. It is also reported that for same ratio of liquid to Gas flow rate, the dehumidification effectiveness is more for the desiccant system using LiCl. Design variables found to have the greatest impact on the performance of the dehumidifier, are desiccant concentration (slope = 2.7), desiccant temperature (slope = –1.4), air flow rate (slope = –0.9), and air humidity ratio (slope = 2.5).


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Author Biographies

Prachi Rai, Department of Mechanical Engineering IIT (BHU) Varanasi, India

Ms. Prachi Rai is a dual degree Master student, currently working in the Department of Mechanical Engineering IIT (BHU) Varanasi, India. Her areas of interest are Modeling of HVAC system, Life Cycle Cost Analysis etc.

S.K. Shukla, Mechanical Engineering Department, Indian Institute of Technology (BHU), Varanasi, India.

Dr. S.K. Shukla is working as Associate Professor in Mechanical Engineering Department, Indian Institute of Technology (BHU), Varanasi, India. He has been post graduated and completed his Ph.D. from IIT Delhi. His areas of interest are Thermal Engineering, Heat and Mass Transfer Analysis in Solar Thermal Systems and Design of Renewable Energy Systems, Modeling of HVAC systems. E-mail: Tele fax; +91-542-6702825.


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