COMBUSTION CHARACTERISTICS OF BIOMASS CHARCOAL PRODUCED AT DIFFERENT CARBONIZATION CONDITIONS

摘要

The combustion properties of spruce chars and spruce forest residue chars were studied in the kineticrnregime by a series of TGA experiments. The work aimed at establishing how the pressure of the char preparationrnaffects the reactivity with oxygen. In the present phase of the work the pressure during char preparation wasrnemployed on a thin layer of biomass with ample ventilation. In this way only negligible pressure effects werernobserved during char combustion. The kinetics of the char burn-off was described by assuming a main reaction and arnside reaction. 12 experiments at three different temperature programs were evaluated by the method of least squaresrnto obtain a dependable kinetic model. A common activation energy of 137kJ/mol gave a reasonable description ofrnboth reactions in all the 12 experiments.