Article

Performance Evaluation of an Efficient Solar Dryer with a Backup Incinerator for Grated Cassava under Makurdi Humid Climate

International Journal of Environment and Bioenergy 03/2012; 1(2):131-139.

ABSTRACT An efficient hybrid solar dryer was designed and constructed at the University of
Agriculture, Makurdi, Nigeria. It consists of solar collector, drying chamber, and incinerator.
The dryer was used for drying at night. The sunshine days and cloudy days drying were
assumed to have taken place in the falling rate period which enabled the use of only one
drying constant. This was used test drying termed no load test (without any farm produce)
and on load (wet grated cassava chips) and for other farm produce. The results obtained showed
that drying was fastest during the solar drying and least during the incinerator drying and the control
drying, respectively. The mean location drying rate efficiencies obtained were 98.8%, 94.7%, and
87.4% for solar dryer, solar-incinerator dryer and incinerator dryer, respectively. The computed
efficiencies for the equipment were 56%, 13% and 16% for solar dryer, solar incinerator dryer and
incinerator dryer, respectively. The dryers can be used to substitute gari dehydration and drying of
other farm produce in rural and semi-urban areas for improved quality.

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