Experimental analysis on the performances of a desiccant wheel regenerated by low grade thermal energy

Many research papers have shown the technical and energy advantages related to the use of desiccant-based HVAC systems instead of traditional ones (with dehumidification by cooling). For these reasons, a test facility has been located in Benevento (Southern Italy), to carry out an experimental analysis on a silica-gel desiccant wheel inserted in an air handling unit which treats outside air only. For this wheel, the regeneration temperature can be as low as 65 °C, obtainable using the thermal wastes from a small scale cogenerator. The objective of this paper is the presentation of the main latest results of the experimental investigation on the desiccant wheel. This analysis is above all related to the variation of the desiccant wheel performance when varying some key parameters, such as the regeneration temperature, the process air inlet humidity ratio and temperature, the ratio between regeneration and process airflow rates. The performances of the wheel have been quantified by means of the following figures of merit: the moisture removal capacity (kg/h), the dehumidification effectiveness and the dehumidification COP. Some interesting results on the wheel performances have been obtained.