凉水井煤自燃关键活性基团氧化释放气体的试验

Oxidative release of gas by key active groups in spontaneous combustion of coal

为探索凉水井煤自燃特征,采用程序升温与漫反射原位红外光谱试验,分析凉水井4-3煤层自燃过程中宏观气体与微观结构动态演变规律及相互作用关系。结果表明:凉水井煤自燃过程中临界温度为60℃,干裂温度为110℃,煤结构高温裂解的C_(2)H_(6)和C_(2)H_(4)气体可作为煤自燃高温阶段的预报性指标气体。通过特征温度下红外光谱,发现煤氧化过程中官能团的消耗与产生主要发生在脂肪烃、芳香烃以及含氧官能团吸收谱带,得出CH_(3)、CH_(2)、C-H、OH及C=O是煤氧化过程中最为活跃的官能团。采用动态灰色关联方法,计算出关键活跃的官能团CH_(3)、CH_(2)、C-H、OH及C=O与CO、CO_(2)、C_(2)H_(4)及C_(2)H_(6)气体的动态关联度,阐明凉水井煤自燃释放气体受这5类官能团的共同影响,煤关联度最高的C=O键在煤自燃反应过程中具有非常重要的作用。

In order to explore the spontaneous combustion of coal in Liangshuijing,the dynamic evolution law and interaction between macroscopic gas and microscopic structure in the spontaneous combustion process of Liangshuijing 4-3 coal seam were analyzed by temperature-programmed and diffuse reflection in-situ infrared spectroscopy experiment.The results show that the critical temperature of coal during spontaneous combustion is 60℃,and the dry cracking temperature is 110℃.The C_(2)H_(6)and C_(2)H_(4)gases from the pyrolysis of coal structure can be used as the indicator gases for predicting the high temperature stage of spontaneous combustion.It is found that the consumption and production of functional groups in the process of coal oxidation are mainly in the absorption bands of aliphatic hydrocarbon,aromatic hydrocarbon and oxygen-containing functional groups.It is concluded that CH_(3),CH_(2),C-H,OH and C=O are the most active functional groups in the process of coal oxidation.The dynamic correlation degree between the key active functional groups CH_(3),CH_(2),C-H,OH,C=O and CO,CO_(2),C_(2)H_(4),C_(2)H_(6)gases is calculated by using the dynamic grey correlation method.The results indicate that the gas released from coal spontaneous combustion in Liangshuijing is affected by these five functional groups.The C=O bond with the highest correlation degree plays a very important role in the spontaneous combustion of coal.