热提质褐煤预氧化后自燃特性变化及其自由基原位分析

发布时间：2018-06-14 11:05

  本文选题：热提质 + 褐煤　； 参考：《化工学报》2017年10期

【摘要】：针对不同温度热提质褐煤新鲜样及其自然环境中储存一定时间后的预氧化样,利用订制的自燃测定实验装置测得各样品的自燃倾向性差异,采用X-band电子自旋共振波谱仪进行自由基动态原位分析,研究预氧化对热提质褐煤自燃特性的影响。结果表明,热提质温度升高,新鲜样的自燃倾向性降低。但随着储存时间延长,105~500℃热提质褐煤发生预氧化,自燃倾向性不同程度地增加,400℃热提质后的预氧化样与原煤一样易自燃。在自燃氧化过程中,与新鲜样不同,预氧化样的吸氧量增加,自由基浓度也增加。预氧化不仅使热提质褐煤自由基增加;且在自燃的加速氧化阶段后期,不断产生自由基,维持氧化自热升温。而400℃热提质褐煤新鲜样在自燃氧化初期消耗大量小分子自由基,损失达80%,因不能持续产生活性自由基难以维持自燃氧化反应进行。
[Abstract]:In view of the preoxidation samples of fresh lignite samples at different temperatures and their natural environment after storage for a certain time, the self-ignition tendency of each sample was measured by using a self-ignition experimental device. The effect of preoxidation on the spontaneous combustion of heat-extracted lignite was studied by using X-band electron spin resonance spectrometer. The results showed that the autoignition tendency of the fresh samples decreased with the increase of the temperature. However, with the prolongation of storage time, preoxidation occurs at 500 鈩，

本文编号：2017165