title: Grindability and combustion behavior of coal and torrefied biomass blends.
abstract: Biomass samples (pine, black poplar and chestnut woodchips) were torrefied to improve their grindability before being combusted in blends with coal. Torrefaction temperatures between 240 and 300 °C and residence times between 11 and 43 min were studied. The grindability of the torrefied biomass, evaluated from the particle size distribution of the ground sample, significantly improved compared to raw biomass. Higher temperatures increased the proportion of smaller-sized particles after grinding. Torrefied chestnut woodchips (280 °C, 22 min) showed the best grinding properties. This sample was blended with coal (5-55 wt.% biomass). The addition of torrefied biomass to coal up to 15 wt.% did not significantly increase the proportion of large-sized particles after grinding. No relevant differences in the burnout value were detected between the coal and coal/torrefied biomass blends due to the high reactivity of the coal. NO and SO2 emissions decreased as the percentage of torrefied biomass in the blend with coal increased.
authors.affiliation: Instituto Nacional del Carbón, INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: M V
authors.initials: MV
authors.lastname: Gil
authors.affiliation: Instituto Nacional del Carbón, INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: R
authors.initials: R
authors.lastname: García
authors.affiliation: Instituto Nacional del Carbón, INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Pevida
authors.affiliation: Instituto Nacional del Carbón, INCAR-CSIC, Apartado 73, 33080 Oviedo, Spain. Electronic address: frubiera@incar.csic.es.
authors.forename: F
authors.initials: F
authors.lastname: Rubiera
mesh_terms: D018533:Biomass; D003031:Coal; D010316:Particle Size; D013696:Temperature
chemical_list: D003031:Coal
keywords: Biomass; Co-combustion; Coal; Grindability; Torrefaction