平朔煤岩显微组分热解过程中HCN的生成

FORMATION OF HCN DURING PYROLYSIS OF PINGSHUO MACERALS

以平朔煤的三种有机显微组分为研究对象,使用石英玻璃管式反应器,在600℃～900℃范围内考察了程序升温热解和快速升温热解过程中HCN形成与释放的规律。实验结果表明,热解反应温度、升温速率和显微组分类型对HCN的释放均有较大的影响。热解温度越高,HCN在三种显微组分气相产物中的生成量越大;热解温度为900℃时,稳定组的HCN收率较大,热解温度为600℃时,镜质组的HCN收率较高,这和不同显微组分中氮的赋存形态有关;与慢速升温热解相比,快速升温热解有利于HCN的释放;与原煤热解过程中HCN的收率相比,显微组分在原煤中的百分含量不是HCN收率的权重系数,显微组分热解生成HCN的过程中有协同效应。

Three macerals, liptinite, vitrinite and inertinite separated from Pingshuo coal were used in this study. The formation of HCN during macerals pyrolysis was investigated using a quartz tube reactor at 600℃～900℃. Both the programmed heating and fast heating pyrolysis have been studied. It was found that the yield of HCN increased with pyrolysis temperature for all three macerals. The yield of HCN during vitrinite pyrolysis was the biggest among the three below 800℃, and that of liptinite was the highest at 900℃. The yields of HCN depended not only on their volatile content but also on the nitrogen functional groups in different macerals. More pyrrole-type nitrogen could form more HCN at lower temperature. The yield of HCN increased with increasing heating rate. Comparing the HCN yield at different period during pyrolysis, it could be found that most of HCN was released at the feeding period. The synergistic effect for the formation of HCN existed in the pyrolysis of acid-washed parent coal.