汞在不同粒度、密度煤炭中分布规律

Mercury distribution of coal in different size and density components

测试了河南田庄、河北邯郸、内蒙古(公乌素、平沟、老石旦)选煤厂原煤中的汞含量。发现田庄选煤厂原煤属于特低汞煤,邯郸和内蒙古的三个选煤厂原煤都属于低汞煤;通过对田庄、邯郸两个选煤厂原煤的筛分浮沉实验,研究了汞在不同粒度、密度煤炭中的分布规律。结果显示随着密度增加,汞含量增加,而且汞主要分布在>1.8的高密度级脉石中,通过洗选可以分别减少这两个选煤厂煤炭中的汞含量50%和60%左右;并且发现两个选煤厂中汞含量与灰分有较好的线性相关性,也说明了原煤中汞的赋存与矿物质密切相关。此研究进一步证明了,煤炭燃烧前洗选不但可以提高发热量,降低无机硫含量,也可以大幅度降低汞含量。

According to the determination results of mercury content of raw coal for five coal preparation plants （ Tianzhuang, Handan, Gongwusu, Pinggou, Laoshidan） , it has been found that raw coal in Tianzhuang coal preparation plant is belong to extremely low mercury coal, the others are low mercury coal; The distribution regularities of mercury in different size and density componens are studied by float-sink test for different size of raw coal of Tianzhuang and Handan plants. The results show that the content of mercury increases with increasing of density and the mercury in coal mostly exist in plus 1.8 high-density gangue, the mercury content of coal could be reduced around 50% by discharging waste for these two plants. It has been found that the mercury content has good linear relationship with ash content of coal, it means that the mercury in coal is mainly associated with minerals. The study conclusions make further prove that coal cleaning before burning not only increase the heating value, reduce the sulfur content, also substantially reduce the mercury content.