Abstract:
Indonesia is the largest coal importer of China. In this paper, the concentrations of 12 elements in 31 imported Indonesia coal samples were determined using inductively coupled plasma mass spectrometry (ICP-MS), atomic fluorescence spectrometry (AFS), direct mercury analyzer. The concentrations of trace elements in imported Indonesia coals were compared and evaluated. The statistical methods of correlation analysis, cluster analysis, factor analysis were used to obtain some useful information about the possible modes of occurrence of these elements. The study shows that imported Indonesian coals containing high mercury coal, three levels of arsenic coal. The average enrichment coefficient of As, Hg is greater than 1, which suggest the migration risk of As, Hg should be concerned. The average concentrations of Be, Cu, Mo, Cd, Sn, Pb in imported Indonesia coals, lower than the Chinese coal and the world coal, which consistent with low ash content of Indonesia coals. The trace elements in this study can be divided into three categories: the first category is summed up as the clay mineral adsorption, including As, Be, Cr, Co, Ni, Cu, Mo, Cd, Sn, Pb, ash; second into the pyrite type, including Hg, total sulfur; third into the carbonate minerals, including Ba. The research of distribution of trace elements in imported Indonesia coals could provide scientific reference for environmental assessment and clean utilization of imported Indonesia coals.