Hydrothermal Carbonization of Organic Material with Low Dry Matter Content: The Example of Waste Whey

摘要

Hydrothermal carbonization at 205°C was evaluated to process waste whey containing 5.9% of dry matter to a coal-like material and process water. Carbonization increased dramatically the heating value, with 15.0 MJ/kg for whey and 25.2 MJ/kg for coal, alongside the carbon fraction, from 38.0% (whey) to 60.4% (coal). Carbonization brought C/H und C/O molar ratios to typical values for brown coal. HTC process water showed a low N/P ratio, and could thus be interesting as phosphorus fertilizer. However, elevated concentrations of phenols and cyanides suggest that further treatment might be necessary.