煤中汞赋存形态及其热解时析出规律研究

利用程序升温热解反应系统，研究了煤中不同形态汞的析出温度，通过积分各析出温度下汞的总析出量来分析各赋存形态的汞所占比例，同时研究了添加CaCl₂后抑制煤热解过程中汞析出的机理。结果表明，实验所选煤中汞主要存在三种赋存形态，其析出温度点分别在220、300和400 ℃；其中，300 ℃析出的汞所占比例最高，为54.18%，从析出温度分析该部分汞主要以HgS的形式赋存。添加CaCl₂对第一和第三赋存形态的汞析出具有抑制作用，改变了其析出温度，对第二赋存形态的汞析出几乎无影响，添加后使得汞析出温度更为集中；抑制析出的主要原因是氧化吸附，添加CaCl₂对汞总析出量基本无影响。

Mercury occurrence mode in coal and its release behavior during pyrolysis

A temperature-programmed tube furnace was set up to investigate the occurrence modes of mercury in coal according to its releasing temperature during pyrolysis. The fraction of mercury in each occurrence mode was determined by calculating the total released amount at different temperature ranges. The mechanism of mercury release inhabitation by CaCl₂ was studied as well. The result showed that there are mainly three occurrence modes of mercury in coal: their release temperatures are 220, 300 and 400 ℃.The secondary mode released at 300 ℃ takes 54.18%, which should be HgS according to its decomposition temperature. The CaCl₂ inhibited the release of mercury at 220 and 400 ℃. The inhabitation is mainly caused by mercury oxidation and adsorption. By adding CaCl₂, the mercury release is focused to a certain temperature but the total release amount is hardly influenced.