title: Nonisothermal thermogravimetric analysis of Thai lignite with high CaO content.
abstract: Thermal behaviors and combustion kinetics of Thai lignite with different SO₃-free CaO contents were investigated. Nonisothermal thermogravimetric method was carried out under oxygen environment at heating rates of 10, 30, and 50°C min⁻¹ from ambient up to 1300°C. Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods were adopted to estimate the apparent activation energy (E) for the thermal decomposition of these coals. Different thermal degradation behaviors were observed in lignites with low (14%) and high (42%) CaO content. Activation energy of the lignite combustion was found to vary with the conversion fraction. In comparison with the KAS method, higher E values were obtained by the FWO method for all conversions considered. High CaO lignite was observed to have higher activation energy than the low CaO coal.
authors.affiliation: Department of Mechanical Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, Thailand.
authors.forename: Pakamon
authors.initials: P
authors.lastname: Pintana
authors.forename: Nakorn
authors.initials: N
authors.lastname: Tippayawong
mesh_terms: D017610:Calcium Compounds; D003031:Coal / Q000032:analysis*; D060729:Coal Ash / Q000032:analysis; D007700:Kinetics; D010087:Oxides; D013696:Temperature; D013785:Thailand; D013818:Thermogravimetry / Q000379:methods*
chemical_list: D017610:Calcium Compounds; D003031:Coal; D060729:Coal Ash; D010087:Oxides; C016538:lime