Effect of pressure and atmosphere during hydrothermal treatment on the properties of sewage sludge-derived solid fuel

Hydrothermal Carbonization of Waste Biomass: A Review of Hydrochar Preparation and Environmental Application

“…Petrović et al [7] found that an increase in temperature (180-260 • C) provides hydrochars from corn cob, olive pomace, and paulownia with significantly elevated HHV (17.31-27.33 MJ kg −1 , 24.35-30.55 MJ kg −1 , and 18.99-28.06 MJ kg −1 , respectively). A similar trend was also noticed for agricultural, algal, organic municipal solid wastes, plant, and woody biomass (16-29, 30-32, 14-32, 17-32, and 21-30 MJ kg −1 , respectively) [43]. Increased HHVs were also noticed during HTC treatment of Miscanthus × giganteus, cotton stalk, and paulownia leaves [19,39,55], while Kojic et al [28] reported increases in both HHV and LHV (58% and 65%) in comparison with raw spent mushroom substrate.…”

“…Also, Minaret and Dutta [42] in their BET analysis evaluated that the surface area of corn husk hydrochar reduced when raising the pressure of the HTC process (from 7.4 to 4.8 m 2 /g). The HHV of the sewage sludge hydrochar showed a continual decrease (from 8.0 to almost 6.5 MJ/kg) with increasing pressure (from 0.1-0.9 to 3.1-5.4 MPa), while the dewatering performance was improved [43].…”