Evaluation of Solar-Assisted Dehumidification Drying-System (I): Study of Drying-Air Properties, Energy and Exergy Analyses, and Some Drying Measures

I.E. Saeed, K. Sopian, Z.Z. Abidin


The aims of this part (I) of the techno-economic evaluation of a solar-assisted dehumidification
drying-system were to carry out an energy and exergy analyses, and to study the drying-air
properties and some drying measures. The exergy inflows to drying chamber were varied
between (0.008-0.173kJ/s) for drying at (35°C, 3.0m/s) to (0.286-0.491kJ/s) at (65°C, 3.0m/s),
while the exergy outflows were ranged between (0.000-0.018) for drying at (35°C, 3.0m/s) and
(0.005-0.173) for (65°C, 3.0m/s). The energy utilization decreased with drying time, but increased
with air temperature and velocity. In addition, graphical representations of drying curves,
dehumidification and regeneration rates of the silica gel were shown.


energy; exergy; drying-air properties; Karkade; Roselle; silica gel

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