The behavior and the kinetics in nitroen and air o ftwo low-rank colas(lignite and xylite) and their blends,as well as the compatibilty of the component coals in the blends were evaluated,in an effort for the rational use of poor coals.The experiments were conducted in a thermobalance system,at non-isothermal heating conditions,with heating rates of 20 and 100 deg C/min,in the temperature range of 25-850 degC.Material particle size was -100 mum.A frist-orde rparallel independent reactions model and a power law model fited successfully the rate data of pyrolysis and combuston,respectively.Activation energy values and reaction orders ranged from 23 to 182 kJ/mol and 0.8 to 2 respectively.The heating rate did not affect the kinetic parameters considerably,however when this was increased the was ncreawed the reactions were shifted to higher temperatures and the rates were greater.The pyrolysis kinetics of lignite/xylite blends could be sufficiently predicted,based on the data of the individual fuels.However,this was not true in the case of char combustion.Blending of lignite with xylite,in any proprotion,seemed to cause some interactions between the component coals in air.
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