Design, development and evaluation of a biomass fueled cabinet dryer for high quality cassava flour production

Abstract

Abstract Cassava, a vital staple crop in developing countries, plays a significant role in ensuring food security and income generation for smallholder farmers. However, the lack of modern drying technology in rural area necessitate the need for a more efficient and controllable drying process which reduces post-harvest losses and ensure better product quality while taking sustainability into account by utilizing biomass as the energy source. Therefore, drying cassava roots to produce high-quality cassava flour was the goal of the biomass heat-generated cabinet dryer, which was designed and built for drying in rural locations. The main components of the dryer include heat exchanger, blower, and drying chamber unit which was designed based on engineering standards utilizing locally available materials. The drying chamber consists of two racks of 10 trays each for drying. The dryer was found to be capable of drying 40, 60, and 80 kg of wet cassava mash each batch, when the loading capacity was 2, 3, or 4 kg/tray. At temperatures ranging from 50 to 115°C, with drying duration of 10 to 120 minutes, thermal efficiency, drying time, and heating energy were investigated. Moisture levels reduced to 10.6%, 11.0% and 11.2% from initial moisture content of 38.21%. At 40 kg, 60 kg, and 80 kg material capacities, drying efficiencies averaged 74.77%, 59.22%, and 88.24%, respectively, with biomass efficiencies 3.0%, 3.5%, and 4.0%. Despite a low biomass efficiency, drying efficiency shows that the dryer is relatively efficient in drying. Hence, biomass fueled dryer should be employed for drying.