硫化矿石自燃的热分析动力学  

Thermal analysis kinetics of sulfide ores for spontaneous combustion

作　　者：阳富强[1,2] 吴超[1,2] 刘辉[1,2] 潘伟[1,2] 崔燕[1,2] 

机构地区：[1]中南大学资源与安全工程学院,湖南长沙410083 [2]中南大学国家金属矿安全科学技术研究中心,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2011年第8期2469-2474,共6页Journal of Central South University:Science and Technology

基　　金：国家"十一五"科技支撑计划项目(2006BAK04B03-02);教育部博士生学术新人奖专项资助项目(1343-7113400111);中南大学优秀博士学位论文扶植项目(2009yb047);中南大学研究生学位论文创新基金资助项目(1960-71131100023);中南大学贵重仪器设备开放中心基金资助项目(ZKJ2009008)

摘　　要：为获取硫化矿石自燃的动力学参数,应用同步热分析仪研究典型硫化矿样在28～800℃之间的氧化热解过程,得出升温速率分别为5,10和15℃/min条件下的TG,DTG和DSC曲线。采用Coats-Redfern积分法,基于11种不同动力学机制模式函数分别对480～580℃之间的热重分析数据就ln[g(a)/T2]对1/T进行相关性分析。研究结果表明:矿样的最大质量损失率分别出现在温度516.597,516.981和580.493℃处;硫化矿石在490～580℃温度区间的氧化热解过程符合一维扩散反应动力学机制;据此求出硫化矿石在升温速率为5,10和15℃/min下的活化能分别为247.009,251.307和196.26 kJ/mol,指前因子分别为1.873×1013,4.259×1013和5.226×109 s-1,并得出其动力学方程。提出以多样本实验条件下所得硫化矿石的活化能值作为其自燃倾向性判定指标的思想,该方法具有测试速度快、试样用量少、测试成本低等优点,可以运用于硫化矿山开采过程中的矿石自燃倾向性判定中。In order to obtain spontaneous combustion kinetics parameters,simultaneous thermal analysis technology was used to test oxidation and decomposition reactions of a typical sulfide ore sample from 28 to 800 ℃.The corresponding TG,DTG,and DSC curves at heating rates of 5,10 and 15 ℃/min were gained.Based on Coats-Redfern integral method,the correlation coefficients of ln[g（a）/T2] versus 1/T for TG datum between 480 and 580 ℃ was analyzed using 11 different kinetics mechanism functions.The results show that the maximum mass loss occurs at temperatures of 516.597,516.981 and 580.493 ℃.The kinetics reaction process of the sample complies with the diffusion one-way transport mechanism.The corresponding activation energy values calculated at 5,10 and 15 ℃/min are 247.009,251.307 and 196.26 kJ/mol,and pre-exponential factors are 1.873×1013,4.259×1013 and 5.226×109 s-1,respectively.And the kinetics functions are also gained.The idea of evaluating spontaneous combustion tendency of sulfide ores by activation energy index is put forward.This method has some excellences with quick test velocity,little quantum of sample consumption,and low test cost,so it can be applied in spontaneous combustion tendency assessment of sulfide ores.

关 键 词：硫化矿石 自燃倾向性 热分析 动力学 活化能 

分 类 号：X915.5[环境科学与工程—安全科学]