淮南煤热分析特性及气体生成物实验研究
2018-08-13张嬿妮陈龙赵靖昱
张嬿妮 陈龙 赵靖昱
摘 要:为了研究淮南矿区主要煤层的自燃特性,选取淮南矿区的五个煤样,采用热红联用仪分别在不同气氛下开展了煤自燃热分析特性及反应气态生成物的产生规律分析。结果表明:虽然各煤样来自不同的矿区,但各个煤样的实验曲线特征具有相似性,确定了各煤样自燃过程中的临界温度T1,干裂温度T2,活性温度T3,增速温度T4和着火温度T5等特征温度点;随着氧浓度的降低,煤样的TG与DSC曲线均存在滞后现象,即氧化相同质量的煤样,氧浓度越低,需要的温度越高;主要针对煤自燃氧化过程中CO,CO2以及H2O的气态产物进行监测,因煤样所含官能团种类相似但数量不同,气体生成物只有数量的差异,而无种类的差异。此研究对于进一步了解煤自燃机理,采取有针对性的防治措施具有一定的理论意义。
关键词:特征温度;红外光谱;氧浓度;气态产物
中图分类号:X 936 文献标识码:A 文章编号:1672-7312(2018)05-0640-05
Abstract:To study the spontaneous combustion characteristics of the main coal seam in Huainan,five coal samples from Huainan were selected.The thermal characteristics analysis of coal spontaneous combustion and the regulation of gaseous products were carried out in different conditions by using the Thermogravimetry-Fourier Transform Infrared Spectrometer.The results show: although the samples come from different mining areas,the experimental characteristic of each coal sample are similar.The critical temperature T1,crack temperature T2,active temperature T3,speedup temperature T4 and ignition temperature T5 were determined.With the decrease of oxygen concentration,the TG and DSC characters of coal samples have hysteresis phenomenon.The lower the oxygen concentration is,the higher the temperature is when the coal samples of the same quality are oxidized.The gaseous products of CO,CO2 and H2O in the process of oxidation were monitored.Due to the types of functional groups contained in coal samples were similar but the quantities were different,the gaseous products were only different in quantity,but not in types.This study had theoretical significance for further understanding and taking prevention measures of the coal spontaneous combustion.
Key words:characteristic temperature;infrared spectrum;oxygen concentration;gaseous products
0 引 言
根据煤氧复合理论,煤自燃的根本原因在于煤氧化放出热量并聚集升温导致[1]。热分析-红外联用仪是一种同步实验,可针对煤自燃过程的热反应特性及红外气体产物特征进行分析,能够得到煤自燃过程中的失重规律和放热特性,并能监测反应过程中气体生成产物。不同煤种因其成煤时期的复杂物理化学作用,导致煤分子结构中官能团种类和数量的差异,进而显示出不同的宏观热分析特征和气体产物规律。淮南地区的煤具有易自燃的属性,因此,对淮南地区煤开展热分析-红外联用实验,掌握淮南矿区主要煤层自燃过程中的特性参数是很有必要的。……
