Donghyeon Kim
Chonbuk National University,Republic of Korea
Title: An experimental study of sorption characterisrics for the sub-bituminous coal considering size effect
Biography
Biography: Donghyeon Kim
Abstract
In this study, adsorption and desorption characteristic were analyzed by changing the particle size of coal in order to estimate the CBM production potential. We used sub-bituminous coal samples from Kotabaru filed in Indonesia and volatile matter, ash and moisture content analyzed. All samples were crushed and they are divided into seven groups with particle size from 50mesh to 20 mm. For each sample, volumetric method was applied to measure the Langmuir pressure (PL), Langmuir volume (VL), and equilibrium time. From results, as particle size increases, Langmuir volume that is the maximum gas content of the sample decreases due to the reduction of specific surface area, but they show a little difference. In contrast, in desorption process, more time was needed for the large particle size to reach an equilibrium state because desorbed gas flow through the longer path and defuses by the concentration difference. In conclusion, desorption characteristics with coal size should be considered because the pore volume, pore size, and effective surface area are different. Moreover, Langmuir isotherm measurement for the lump coal considering cleat spacing is essential to obtain a more precise CBM production profile.
