煤自燃标志气体的阶段特征实验研究

摘要

Based on temperature-programmed experiments, we determined the spontaneous combustion index gases( CH4 , C2 H6 ,C2 H4/C2 H6 value,ΔCO/ΔO2 value and O2 )of lignite, Bulianta non caking coal and Baode gas coal. The results showed that: CO was produced in the whole oxidation process, CH4 was produced at the same time with CO, but the concentration of CH4 was lower than that of CO,and it had different regularities in different coals;C2 H4 was produced later than CO and CH4 ,followed by C2 H4 being produced at last(in relatively high temperature stage).Using single CO gas index in judging coal spontaneous combustion stage should be avoided, because the characteristic gas manifestation was different in different stages of coal oxidation,instead,in order to improve the reliability of coal spontaneous combustion prediction,more different characteristic gases should be adopted as the early warning indicators of coal spontaneous combustion stage. For testing coal,CO and C2 H4 should be selected as the index gases,while CH4 ,C2 H6 ,C2 H4/C2 H6 value,ΔCO/ΔO2 value and O2 as the assisted early warning indicators of spontaneous combustion.%基于程序升温实验，对东胜褐煤、补连塔不黏煤、保德气煤的 CH 4、C2 H 6、C2 H 4／C2 H 6值、ΔCO／ΔO2值、O2等自燃标志气体进行测定。结果表明：CO 的产生存在于整个氧化过程；CH4出现的时间与 CO 相当，但浓度低于 CO，且在不同煤种中有不同的显现规律；C2 H 6出现时间晚于 CO 和 CH4，C2 H4出现的时间最晚，在较高温度段才出现。煤氧化不同阶段特征气体的表现形式不同，判断煤的自燃阶段时避免采用单一 CO 气体指标，应选取不同的特征气体作为煤自燃阶段的预警指标以提高煤自燃预报的可靠性。对于测试煤种，应选择 CO 和 C2 H 4作为煤炭自燃氧化的指标气体，并将 CH4、C2 H 6、C2 H4／C2 H 6值、ΔCO／ΔO 2值、O 2作为自燃辅助预警指标。