This study investigated the thermal properties and activation energies of raw and torrefied poultry litter samples in the range of 250-300 degrees C by using thermogravimetric analysis (TGA). Four heating rates, 5 degrees C/min, 10 degrees C/min, 20 degrees C/min, and 30 degrees C/min were applied during the thermogravimetric analysis. Furthermore, co-combustion of raw and torrefied poultry litter samples with low-rank Turkish lignite was studied and the effect of the blending ratio on thermal reactivity of poultry litter was also investigated. Raw poultry litter has the highest fuel reactivity with the lowest ignition and burnout temperature as compared to both torrefied poultry litter samples and their blends. Torrefaction had a serious effect on the decomposition temperatures of the samples (i.e. the temperature at the maximum derivative thermogravimetric curve, ignition, and burnout temperatures). Decomposition temperatures increased with torrefaction temperature and derivative thermogravimetric curves shifted towards higher temperatures. The combustion performances of all lignite blended samples were also found to be better than lignite. Furthermore, as blends contain more poultry litter which is torrefied at a higher temperature, the fuel properties of blends improve and get closer to lignite. (C) 2019 Elsevier Ltd. All rights reserved.