Feasibility of Liquid Desiccant Dehumidification System for Low-Temperature Drying Applications

This study analyses the feasibility of a LDD system for the drying process of vegetables and fruits. An experimental setup was fabricated to observe the correlation between the relative humidity and airflow velocity. In this investigation, the influence of airflow velocity on relative humidity at the outlet and the moisture extraction rate is analyzed. Results indicate that an increase in air velocity enhances the drop in relative humidity, which is very essential for the drying of products. However, beyond a particular limit of air velocity, the moisture extraction rate demonstrates a decrease. This decrease is due to the diminishing quantity of liquid desiccant solution necessary in relation to the escalating air velocity. Achieving a relative humidity of 25.66% requires a temperature rise of 34.8°C in the convective system, while the LDD system achieves the same with a lower temperature rise of 32.2°C under identical inlet conditions. This indicates that the LDD system provides better drying conditions compared to conventional methods. Hence, the LDD system proves to be superior in preserving quality, texture, and other essential properties of perishable products in the drying process. These findings contribute to the usefulness of the LDD system for drying operations at low temperatures.