Essential Role of Trace Elements in Continuous Anaerobic Digestion of Food Waste

The purpose of this study is to explore the possibility of long-term sustainable anaerobic digestion of food waste in semi-continuous single-stage reactors by supplementing trace elements. Compared with the failure of anaerobic digestion of food waste after prolonged operation, a clearly enhancement of process performance was observed by supplementing a model trace element solution. Although the sustainable continuous anaerobic digestion of food waste could not be achieved by supplementing a model trace element solution, the correlation of process performance and trace element profile during continuous operating period revealed that the declining performance was highly likely due to the decreasing trace element concentrations, especially Co, Mo, Ni and Fe. This finding was expected to provide a promising strategy for sustainable anaerobic digestion of food waste.