Abstract
The aim of this work is to apply Hydrothermal Carbonisation (HTC) to different kinds of sludge such as thickened sludge, digested sludge and dewatered sludge, and compare the composition of the solid produced by the process, i.e. hydrochar, with soil and biosolid legislations: Table 1. For the purpose, experimental tests were performed at different operating conditions, namely three temperatures (190, 220 and 250 °C) and two reaction times (30 and 60 minutes).