Production of animal feed from food waste or corn? Analyses of energy and exergy

Abstract

The aim of the study was to investigate the energy and exergy consumption of the food waste dryer and then to compare the energy required to produce animal feed with the waste drying method and conventional methods. The required waste from the kitchens has been collected so that each collection period was considered as a block due to having different moisture content. The results showed that the amount of energy consumed increased along with increasing temperature to 29.23 kJ, also wasted exergy and the rate of recovery was significantly increased, but the efficiency of the device decreased significantly. Over time, energy consumption, energy consumption ratio, improvement potential rate have increased, but exergy efficiency reduced. Obtained results suggest that the conversion of food waste into animal feed requires 1.8 MJ per kg less energy. Finally, feed production from food waste is more affordable than agriculture because not only we need less energy than but also we don't spend money to get initial materials.