Heat capacity measurements of various biomass types and pyrolysis residues

This study aims at measuring heat capacity on a large range of biomass types and on pyrolysis chars obtained under conditions representative of industrial reactors for further use of these data in thermal conversion models. As expected, linear increase could be observed with temperature for the 21 biomasses tested between 313 K and 353 K. The relative difference of heat capacity between the different biomasses was significant but lower than 20%, with values ranging from 1300 to 2000 J kg−1 K−1. The sample form, either in block or powder, did not seem to have any influence. Values of about 1000 J kg−1 K−1 were measured on chars, whatever the pyrolysis temperature. These values are in the same order of magnitude as those extrapolated from literature correlations. As expected, linear increase could be observed with temperature, except in the range 353–513 K, in which an exothermal phenomenon of recombination seems to occur inside the char.