Preparation and Characterization of Optimized Hydrochar from Paper Board Mill Sludge

The amount of Paper Board Mill Effluent Treatment Plant Sludge (PBM-ETPS) dumped from paper mills are huge and its conversion into hydrochar for the purpose of energy has broad prospects. This study investigated the optimum conditions for the production of PBM-ETPS derived hydrochar (PBM-ETPSH) through Reponse Surface Methodology (RSM) for more surface area and pore volume with minimal hydrogen to carbon (H/C) and oxygen to carbon (O/C) ratios. The PBM-ETPSH had higher heating value (HHV) of 18.39 MJ kg−1 with fixed carbon percentage of 15.6. Our results showed a reduction in H/C (35.05%) and O/C (43.7%) ratios confirming the coalification of optimized PBM-ETPSH. Thermogravimetric investigations of blending PBM-ETPSH with coal in 1:1 ratio increased its HHV to 22.25 MJ kg−1 making it suitable as an energy alternative for paper mills.