Oxidation characteristics of a cellulose-derived hydrochar in thermogravimetric and laminar flow burner experiments

Synthetic lignite was prepared by hydrothermal carbonization, in which minerals typical for coal ashes were incorporated during hydrothermal carbonization allowing us to study the catalytic effect of ash components on the oxidation rate of the fuel. Chemically leached lignite using hydrochloric acid was applied as reference material. Combustion experiments were performed by thermogravimetric analysis under chemically controlled conditions and in a laminar flow reactor under pore-diffusion limitation. The investigation of the hydrochar in the laminar flow reactor provided gas temperatures and heating rates typical for pulverized coal combustion. The combustion rate of the chemically leached lignite was found to be comparable to the hydrochar. Furthermore, the catalytic effect of incorporated iron oxide was detected in both combustion experiments. (C) 2016 Elsevier B.V. All rights reserved.