Gasification of the Chars from Low Quality Adana-Tufanbeyli Lignite

Adana-Tufanbeyli lignite which is one of low quality Turkish coals has not been properly investigated in terms of its gasification characteristics. This paper is almost the first study dealing with the gasification of the chars from Adana-Tufanbeyli lignite. For this purpose, Adana-Tufanbeyli lignite was first carbonized under neutral condition which was provided by nitrogen flow, and the obtained char was further gasified using nitrogen/oxygen mixtures in different ratios. Carbonization experiments of the lignite were conducted under nitrogen flow of 100 mL/min in a tube furnace by heating from ambient to 900°C with a heating rate of 10°C/min. Hold time of 30 min was allowed at the final temperature to assure that the process is completed, and then the sample was cooled to room temperature in the furnace under nitrogen flow. Gasification experiment of the char was carried out using a thermogravimetric analyzer from ambient to 900°C with a heating rate of 10°C/min under the flow of nitrogen/oxygen mixtures. That is, the compositions of these gas mixtures were (5 % O2 + 95 % N2), (10 % O2 + 90 % N2), and (15 % O2 + 85 % N2). In all cases, nitrogen is the dominant ingredient, and the concentrations of oxygen are less than that in air to form partial oxidation conditions. TG (Thermogravimetric) and DTG (Derivative Thermogravimetric) analyses profiles were used to examine the relative thermal reactivity of the char under investigated conditions. Gasification yields were interpreted depending on the gasification temperature. Fourier Transform Infrared (FTIR) spectroscopic investigations for both the char and the solid remnant from gasification run were also carried out.