Characterization of fuel properties for coal and torrefied biomass mixtures

Recently, there has been growing interest in co-liquefaction of coal with biomass because biomass has potential to substitute as a cheap hydrogen-donor and enhance liquid yields during direct coal liquefaction. In addition, inclusion of biomass can reduce greenhouse gas emission compared to solely coal-based processes. This paper presents characterization of coal, biomass, torrefied biomass and mixtures of coal with biomass and torrefied biomass to be used for direct liquefaction for the production of liquid fuels. Samples of yellow-poplar (YP) and red maple (RM) biomass collected from Appalachian logging residue and West Virginia Kingwood bituminous coal (C) were used in this study. The red maple and yellow-poplar samples were torrefied at 300 °C to produce torrefied red maple (TRM) and torrefied yellow-poplar (TYP), respectively. The untorrefied and torrefied samples were mixed with coal in a 1:1 ratio (by weight) creating coal-biomass and coal-torrefied biomass mixtures to be used as feed for co-liquefaction. In addition, untreated yellow-poplar and coal samples were tested as controls. All samples and mixtures were characterized for calorific value and underwent proximate, ultimate, and thermo-gravimetric analyses. The volatiles produced during thermo-gravimetric analysis were tested for chemical functional groups present in the products.