Neco Model Questions Vol1 2020 Agricultural Science Question 25

A farmer harvests 5 000 kg of fresh cassava roots with an initial moisture content of 65 % (wet basis). The roots must be dried to a final moisture content of 20 % (wet basis) for safe storage. The dryer removes water at a constant rate of \(0.8\) kg per hour for every 100 kg of fresh cassava, but the rate falls by 10 % after each 5 % absolute reduction in moisture content above the target. After drying, the stored cassava loses moisture equal to 0.5 % of its dry weight each month because of respiration.\n(a) Estimate the total drying time (in hours) required to reach the target moisture.\n(b) Calculate the total electrical energy consumed if the dryer uses 5 kWh per hour.\n(c) Determine the net weight of cassava after 3 months of storage.