The forced convection biomass and solar collector dryer for drying seaweed using exhaust fan

The natural process of drying seaweed takes a long time depending on the sunlight. In addition, the effects of weather, seasons, and the day-night cycle make this process more limited and not fully controllable. The moisture content of post-harvest seaweed is about 92.5%, requiring a relatively long drying time. The design of the dryer developed in this study consists of a solar collector equipped with an exhaust fan—which serves to accelerate the forced heat convection from the collector to the drying chamber and the air heating system using a solar collector with rock bed heat storage material. This paper investigated the drying process by using solar collectors, biomass, and hybrid to dry the seaweed. The method was by testing the activity of the prototype of solar collector unit using rock bed system arranged on solar collector. The results showed at an average solar radiation intensity of 957.48 W/m2 and an average collector temperature of 79.53°C, the solar collector functions maximally by generating a drying room temperature. At an average of 52.89°C, the spreading of heat from the solar collector reaches every drying tray for the process of drying the seaweed. The average of drying rate obtained by testing on solar collector, biomass and hybrid was 0.0123 gram/sec for two days, 0.0569 grams/sec for 400 minutes, and 0.0893 grams/sec for 300 minutes respectively. The efficiency of drying rate for solar collector, biomass, and hybrid was 4.48%, 10.31%, and 13.36% respectively.