煤矿中硫铁化合物的氧化动力学研究

摘要

Heat releasing of sulfur compounds in oxidation is one of the reason why coal spontaneous combustion.The thermal decomposition process and non-isothermal decomposition kinetic of sulfur iron compounds was studied by TG-DSC.The results show that the samples within 179.1 ～ 287.75 ℃ gradually phase transformation,staring pyrolytic oxidation FeS2 within 403.5 ～ 493.75 ℃,within 611.65 ～ 792.25 ℃ ferric sulfate (or ferrous sulfate) stepwise decomposition,pyrolysis weightlessness maximum value.By using thermal gravimetric analysis test methods,establish pyrite compound oxidation kinetics model of sulfur at different stages,the non isothermal kinetic data is analyze by Friedman method,Kissinger method,and Starink method,the kinetic parameters of thermal decomposition reaction were obtained,which could provide the basis for comprehensive criteria for spontaneous combustion of sulfur iron.%硫铁化合物氧化放热是引发煤炭自燃的原因之一,运用XRD、TG-DSC技术分析硫铁化合物的热分解过程和非等温热分解机理.研究表明,硫铁化合物分解包括3个阶段:在179.1 ～287.75℃内逐步进行物相转化,403,5～493.75℃内开始FeS2的氧化热解,611.65 ～792.25℃内发生硫酸盐(或亚硫酸盐)逐步分解,热解失重达到最大值.运用Friedma法、Kissinger法、Starink法对非等温动力学数据进行分析,3个阶段的表观活化能分别是96,174,230 kJ/mol.各阶段样品稳定性逐渐提高,为硫铁化合物自燃的综合判据提供依据.