锌镁铝层状双氢氧化物对煤自燃的阻化特性

煤炭自燃的发生严重影响着煤矿的安全生产,添加阻化剂是预防煤炭自燃的常用技术手段之一。采用热重/差热扫描-傅里叶红外光谱(TG/DSC-FTIR)联用技术研究了锌镁铝类水滑石(Zn_1Mg_2Al_1-CO_3-LDHs)对煤炭自燃的阻化特性和机理,测试了该阻化剂作用下,煤自燃过程中质量、特征温度、热效应和气体产生量等参数的变化规律。测试结果表明,吸热是Zn_1Mg_2Al_1-CO_3-LDHs抑制煤自燃的主要原理,煤样中阻化剂的添加能够提高煤的脱水脱附最大速率点、缓慢氧化温度和煤样的起始放热温度,而且可以降低煤样的最大释热功率,同时对煤样氧化过程中CO2的产生有轻微的促进作用,阻化率随添加量的增大呈线性增加,研究表明Zn_1Mg_2Al_1-CO_3-LDHs对煤自燃有良好的抑制作用。

Inhibiting effects of Zn/Mg/Al layer double hydroxide on coal spontaneous combustion

Coal spontaneous combustion is a serious threat for the production of coal mines.Application of inhibitors is one of widely used method to prevent coal spontaneous combustion.TG/DSC synchronous analyzer coupling with Fourier infrared spectrometer (FTIR) was employed to investigate the inhibiting effects of Zn1Mg2Al1-CO3-LDHs on coal spontaneous combustion.Inhibiting effects were evaluated from standpoints of quality,characteristics temperatures,thermal characteristics,and gases products during the process of coal spon-taneous combustion.Experimental results show that the endothermic effect resulted from pyrogenic decomposition of Zn1Mg2Al1-CO3-LDHs was the main reason that Zn1Mg2Al1-CO3-LDHs inhibited coal spontaneous combustion.The temperature corresponding to the maximum rate of dehydration and desorption,slow oxidation temperature,and temperature started to release heat could be increased by Zn1Mg2Al1-CO3-LDHs.Nevertheless,Zn1Mg2Al1-CO3-LDHs can reduce the maximum heat release power of coal samples.Meanwhile,it can slightly promote the production of CO2 during the oxidation process.All of these results indicate that Zn1Mg2Al1-CO3-LDHs exhibited great inhibiting effects on coal spontaneous combustion.