School of Mining Engineering, North China University of Technology
Hebei Provincial Key Laboratory of Mining Development and Safety Technology

煤自燃火灾是井下常见的灾害之一，影响煤自然发火的因素有很多，煤中过渡金属离子就是其中之一，但以往的研究更多是侧重于金属离子螯合剂在热力学等方面的影响，而煤中过渡金属离子形成螯合物后，其对煤自燃影响的相关研究还相对较少，为探究金属离子螯合剂抑制煤自燃的效果，将5种金属离子螯合剂溶解于去离子水中，制备质量分数为 5%的金属离子螯合剂溶液。随后将煤样和金属离子螯合剂溶液按照质量比 4∶1 充分搅拌，得到阻化煤样。采用程序升温-气相色谱试验、孔隙结构试验、红外光谱试验，分析加入螯合剂后指标气体CO的浓度变化，螯合剂螯合过渡金属离子后对孔隙结构的影响与螯合煤中过渡金属离子前后煤中活性基团的含量。结果表明：经金属离子螯合剂处理后的煤样CO首次产生的温度点均有推迟，且产生量较原煤减少，金属离子螯合剂可以达到抑制煤自燃的效果；金属离子螯合剂与煤中过渡金属离子可以形成以配位键连接的螯合物，这些螯合物可减小煤的比表面积与孔隙、孔体积的大小，使煤氧复合反应降低；同时分析红外光谱试验结果发现，形成螯合物的过渡金属离子失去催化能力，难以催化煤中甲基—CH3、亚甲基—CH2-与羧基—COOH的转化反应，使煤中官能团能在常温状态下难以被活化，从而抑制了煤自燃的发生；此外，有机膦酸型金属离子螯合剂相对于氨基羧酸型螯合剂对煤自燃的抑制具有更好的效果。

Coal spontaneous combustion is one of the common disasters in underground mines. There are many factors that affect the spontaneous combustion of coal. Transition metal ions in coal are one of them. However, the previous research focused more on the effect of metal ion chelating agents on thermodynamics and other aspects. However, there are relatively few studies on the effect of coal spontaneous combustion after transition metal ions in coal form chelates. For the effect of spontaneous combustion, raw coal samples and coal samples with 5% concentration of metal ion chelating agent were prepared. The change of CO gas concentration after adding chelating agent, the effect of chelating agent on pore structure after chelating transition metal ions and the effect of chelating transition metal ions in coal before and after chelating. The content of reactive groups in coal. The results show that the coal samples treated with metal ion chelating agent have a delayed temperature point for the first generation of CO, and the generation amount is less than that of raw coal. The metal ion chelating agent can achieve the effect of inhibiting spontaneous combustion of coal; Metal ions can form chelates linked by coordination bonds. These chelates can reduce the specific surface area, pore and pore volume of coal, and reduce the coal-oxygen recombination reaction. At the same time, the infrared spectrum experiment was analyzed to form chelates. The transition metal ions lose their catalytic ability, and it is difficult to catalyze the conversion reaction of methyl —CH3, methylene —CH2- and carboxyl —COOH in coal, so that the functional groups in coal can be difficult to be activated at room temperature, thereby inhibiting the spontaneous combustion of coal. In addition, the organic phosphonic acid type metal ion chelating agent has a better effect on the inhibition of coal spontaneous combustion than the aminocarboxylic acid type chelating agent.

河北省自然科学基金资助项目(E2020209111)

王福生，张朝阳，刘向群，等. 金属离子螯合剂抑制煤自燃试验研究[J]. 煤炭科学技术，2023，51（S1）：132−140.

WANG Fusheng，ZHANG Chaoyang，LIU Xiangqun，et al. Experimental study on suppression of coal spontaneous combustion by metal ion chelating agents[J]. Coal Science and Technology，2023，51（S1）：132−140.