School of Environment and Safety, Taiyuan University of Science and Technology, Taiyuan, Shanxi, 030024, People's Republic of China.
Environ Sci Pollut Res Int. 2017 Oct;24(30):23578-23583. doi: 10.1007/s11356-017-9980-7. Epub 2017 Aug 30.
The utilization of coal gangue in power plants has become a new anthropogenic discharge source of mercury and attracted much concern in China. It is crucial to obtain the information about the mercury release during thermal treatment of coal gangue. In this study, the mercury release behavior of two coal gangues selected from two power plants were studied under different thermal treatment conditions of heating rate, residence time, and atmosphere. The results of mercury release profile show that the specified release temperature ranges for the different modes of occurrence of Hg are scarcely affected by the heating rate of 10, 20, and 40 °C/min. A higher heating rate could promote the Hg release to some extent. The mercury release ratio gradually increases with the extension of residence time for both coal gangues. The oxidizing environment has a positive effect on mercury release < 600 °C and has a minor effect > 600 °C. Mercury in coal gangue is more volatile than coal gangue matrix and the mercury in GD coal gangue is more easily released out than that in ED coal gangue.
煤矸石在电厂中的利用已成为人为汞排放的新来源，在中国引起了广泛关注。了解煤矸石在热处理过程中汞的释放情况至关重要。本研究选择来自两个电厂的两种煤矸石，在不同的热处理条件（升温速率、停留时间和气氛）下，研究了汞的释放行为。汞释放特性的结果表明，不同赋存形态汞的特定释放温度范围几乎不受 10、20 和 40°C/min 的升温速率的影响。较高的升温速率可以在一定程度上促进汞的释放。对于两种煤矸石，随着停留时间的延长，汞的释放比例逐渐增加。氧化环境对<600°C 汞的释放有积极影响，对>600°C 汞的释放影响较小。煤矸石中的汞比煤矸石基质中的汞更易挥发，GD 煤矸石中的汞比 ED 煤矸石中的汞更容易释放出来。
