Energy efficient liquid desiccant-based dryer Milind V. Rane a, * , S.V. Kota Reddy b , Roshini R. Easow a a Heat Pump Laboratory, Mechanical Engineering Department, IIT, Powai, Mumbai 400076, India b Mechanical Engineering Department, Fr C Rodrigues Institute of Technology, Sector 9A, Vashi, Navi Mumbai 400703, India Received 16 March 2004; accepted 19 July 2004 Abstract A liquid desiccant-based dryer is developed that has higher energy efficiency compared to conventional hot air based drying systems used in industrial and agricultural sectors. Two-stage regeneration of the liq- uid desiccant, an aqueous solution of calcium chloride, is used to improve the energy efficiency. It is dem- onstrated that the liquid desiccant-based dryer is techno-economically superior. Contacting device is an important component in the absorber and regenerator of a liquid desiccant system. Carryover of liquid des- iccant into the process and/or regenerated air streams is eliminated with the novel contacting device, which has 120–185% greater surface density compared to conventional packing. The air side pressure drop through the contacting device is very low. This paper presents the experimental results of a liquid desic- cant-based dryer, designed for a paper tray drying application. It also includes the effect of variation of operating parameters and that of solution heat exchanger on specific moisture extraction rate (SMER). The average SMER of the liquid desiccant-based dryer is experimentally found to be 1.5 kg/kW h of heat. Energy savings and resultant reduction in CO 2 emissions is about 56% compared to conventional hot air- based dryer. Benefits will be more while drying temperature sensitive herbal, agricultural and pharmaceu- tical products. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: Liquid desiccant; Contacting device; Two stage regenerator; Liquid desiccant dryer 1359-4311/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.applthermaleng.2004.07.015 * Corresponding author. Tel.: +91 22 2576 7514; fax: +91 22 2572 4544. E-mail address: ranemv@iitb.ac.in (M.V. Rane). www.elsevier.com/locate/apthermeng Applied Thermal Engineering 25 (2005) 769–781