Mathematical modelling and exergo-environmental analysis of drying potato samples in a waste heat-based convective dryer

•Waste heat convective dryer utilizes the waste of flue gas to dry food materials.•The proposed dryer took 240 min to complete drying at a temperature of 70 °C.•Midilli et al. model best fits the drying kinetics of potatoes in the proposed dryer.•Moisture diffusivity of dried potato sample is (4.22 ×10−10-11.67 × 10−10) m2/s.•Proposed dryer reduces energy requirement, CO2 and entropy significantly.