硫化矿氧化自热性质测试的新方法

New test method of oxidation and self-heating properties of sulfide ore samples

介绍一种新的测试硫化矿样氧化自热性质的方法。该套实验装置由程序控温箱、金属网篮、热电偶以及温度自动记录仪等构成。通过设置不同的恒温条件,运用该套实验系统首次测试3种不同硫化矿样的氧化自热性质,得出各矿样在不同恒温条件下的自热规律;利用交叉点温度法解算出3种矿样(硫铁精矿、高硫精矿、原矿)的表观活化能分别为13.7366、21.3817、36.2350kJ/mol,比较3种矿样的自燃倾向性。结果表明:随着恒温温度的升高,矿样的自热幅度变大,温度交叉的速度变快;硫铁精矿的表观活化能最小,原矿的表观活化能最大,这与硫精矿更容易发生自燃的现象一致。与传统的研究硫化矿石氧化自热性质的实验方法相比,该方法的测试成本低、操作简便、可重复性强,用于判定硫化矿石的自燃倾向性有一定的适用性。

A new experimental method to test the oxidation and self-heating properties of sulfide ore samples was introduced.This test system is composed of procedure temperature-controlled chest,wire-mesh basket,thermoelectric couples,and auto-recording thermometer.By changing the constant temperature conditions,three sulfide ore samples were tested for the first time by this new method.The self-heating law curves at different temperatures were gained,and the corresponding apparent activation energies of three samples（iron sulfide concentrate,high-sulfur concentrate and original ore） were calculated by crossing-point temperature method,which were 13.736 6,21.381 7 and 36.235 0 kJ/mol,respectively;moreover,the spontaneous combustion tendencies of these samples were compared.The results show that with increasing constant temperature,the self-heating range of samples increases,and the temperature crosses more quickly;the apparent activation energy of the sulfur iron concentrate is the least,while that of original ore powders is the largest,which is consistent with the phenomenon that sulfide concentrate cause spontaneous combustion more easily.Compared with the traditional test device,this new experimental method has some advantages of low test cost,convenient operation and good operation repeatability,so it is suitable for evaluating spontaneous combustion tendency of sulfide ores.