Release behavior of trace elements from coal during high-temperature processing

High-temperature coal utilization processes (combustion, gasification and pyrolysis) emit toxic trace elements into the atmosphere, where they affect the environment and human health. We carried out coal combustion and gasification experiments using several kinds of coals at various temperatures and atmospheric conditions to examine the release behavior of trace elements. Results showed that Group 1 and 2 metals such as Hg, Se, Sb, and Zn were partly released from coal during combustion, gasification and pyrolysis. Oxygen or steam in the operating atmosphere affected the behavior of Hg, Se, Sb, and Zn release from coal.

Graphical abstractAs for the release behavior of trace elements from coal, the residual fractions of Zn and Sb under combustion were greater than in the case of pyrolysis, and Se was smaller. Release of Se and Sb was promoted and release of Hg was suppressed by the existence of steam in atmosphereFigure optionsDownload full-size imageDownload as PowerPoint slide