Microwave drying of a low-rank sub-bituminous coal

A comparison study on the deoxygenation of coal mine methane over coal gangue and coke under microwave heating conditions

“…The graphitization degree of carbonaceous materials in coal gangue was 82.56% after microwave radiation at 650°C, demonstrating that microwaves are the main reason for graphitization of carbonaceous materials. Some studies [55,56] have shown that microwaves have a tremendous influence on graphitization of carbonaceous substances (e.g., petroleum coke and coal). When the pre-heating temperature is 500°C and 800°C, the graphitization degree is 31.40% and 88.37% respectively.…”

Development of a 10 Kw Microwave Applicator for Thermal Cracking of Lignite Briquettes

“…High power microwave heating of coal with exposure time of few seconds increases significantly the grindability Binner et al (2014), and consequently is beneficial for the overall efficiency of the gasifier. Microwave heating of lignite is much faster than conventional heating of coal Pickles et al (2014) (with the value r = 5.48 − 0.73j for fresh lignite, the skin depth is about 6 cm). This work presents the design of a microwave applicator used for continuous volumetric heating of lignite briquettes together with a Comsol multiphysics model used to calculate the power density, temperature, displacement and stress field in the applicator parts.…”

Drying kinetics of coarse lignite particles in a fixed bed

“…Thin-layer drying models have been adopted to coal drying in a few studies [21][22][23][24]. Pickles et al investigated microwave drying of a lowrank sub-bituminous coal [21].…”