Abstract
In this study, the proximate analyses, such as volatile materials (VM), fixed carbon (FC), and higher heating value (HHV), were determined for 20 lignite samples from different areas of Turkey. The lignite samples have been tested with particle size of 0-0.05 mm. Combustion heats (higher heating values, HHVs) of 20 lignite samples obtained from different Turkish sources were determined experimentally and calculated from both ultimate and proximate analyses. The HHVs (MJ/kg) of the lignite samples as a function of fixed carbon (FC, wt%) or volatile materials (VM, %) was calculated from the following equations:
HHV = 0.2997FC + 11.1170 (1) HHV = -0.3225VM + 42.223 (2)
The correlation coefficients for Eqs. (1) and (2) were 0.9820 and 0.9686, respectively. The combustion heats calculated from Eqs. (1) and (2) showed mean differences of +0.4% and +0.4%, respectively.