Development of prototype solar-biomass hybrid dryer and its performance evaluation using salted fish (Cynoglossus spp.)

Abstract

Salted and dried fishes are the source of low cost dietary protein. Solar drying is an alternative method to traditional open sun drying to produce high quality product and minimise the post-harvest losses. The solar-biomass hybrid dryer (in which solar energy and heat energy from biomass burning are integrated) is gaining momentum. In the present study, a solar-biomass hybrid dryer (SBHD) was fabricated using polycarbonate sheet as solar collector which has advantages of longer durability over glass and polythene sheets. Coconut husk with shell was used as the source of biomass. Salted soles (Cynoglossus spp.) were used to evaluate the drying efficiency. Temperature and relative humidity recorded in the dryer during the experiment were in the range of 35 to 50oC and 24 to 40%, respectively. The drying rate curve of salted soles dried in SBHD did not show constant rate drying period. Drying efficiency of solar energy and biomass energy in the designed dryer was 10.66 and 34.66% respectively. The overall drying efficiency of the SBHD was 18.33. Mathematical modeling of the data on drying indicated that the Page model describes satisfactorily the drying characteristics of salted soles in SBHD.