摘要
煤自燃的频繁发生对煤矿安全生产构成了严重威胁。阻化剂防灭火技术在防治煤自燃方面发挥了重要作用。微胶囊材料是一种具有良好预防煤自燃效果的复合型灭火材料。选取聚乙二醇6000(PEG6000)为壁材,乙二胺四乙酸(EDTA)为芯材,利用熔化分散冷凝法制备出芯壁比分别为1∶2、1∶3、1∶4、1∶5的微胶囊化乙二胺四乙酸。利用SEM对微胶囊的表面形貌进行表征,结果表明,PEG6000有效包覆在EDTA表面,成功制备了新型PEG6000-EDTA阻化微胶囊。采用热分析实验研究了不同芯壁比阻化微胶囊对煤样自燃特性的影响,掌握了阻化煤样的分阶段特征与特征温度点的热释放规律。结合热动力学参数,分析了不同芯壁比阻化微胶囊对煤自燃的阻化机理。研究表明:不同芯壁比阻化微胶囊的热反应性及阻化机制存在差异,其芯壁比为1∶3时效果最佳。确定了乙二胺四乙酸微胶囊阻化剂对煤自燃具有化学阻化作用,能够降低煤的失重率,使T_(1)和T_(3)温度分别提高12℃和34℃,而且可以大幅度降低30~200℃和325~683℃放热量。表观活化能的计算表明,在P_(1)和P_(3)两个阶段,抑制煤样的活化能分别为22.96 kJ/mol和54.98 kJ/mol,分别比原煤高4.14 kJ/mol和13.04 kJ/mol,证明了阻化微胶囊可有效的提高活化能抑制来煤自燃。研究表明乙二胺四乙酸微胶囊阻化剂对煤样具有良好的抑制作用,可有效抑制煤自燃反应进程。
The frequent occurrence of coal spontaneous combustion poses a serious threat to the safety of coal mine production.Inhibitors have played an important role in preventing and controlling spontaneous combustion of coal.Microcapsule material is a composite fire extin⁃guishing material with good effect of preventing spontaneous combustion of coal.In this paper,polyethylene glycol 6000(PEG6000)is se⁃lected as the wall material and ethylenediaminetetraacetic acid(EDTA)as the core material,and the core-to-wall ratios of 1∶2,1∶3,1∶4,1∶5 microencapsulated EDTA.The surface morphology of the microcapsules was characterized by SEM.The results showed that PEG6000 was effectively coated on the surface of EDTA,and a new type of PEG6000-EDTA inhibitor microcapsules was successfully pre⁃pared.The effects of different core wall specific inhibitor microcapsules on the spontaneous combustion characteristics of coal samples were studied by thermal analysis experiments.The phased characteristics of the inhibited coal samples and the heat release law of the character⁃istic temperature points were mastered.Combined with thermokinetic parameters,the inhibition mechanism of microcapsules with different core wall ratio on coal spontaneous combustion was analyzed.The results show that the thermal reactivity and inhibition mechanism of mi⁃crocapsules with different core wall ratio are different,and the effect is the best when the core wall ratio is 1∶3.It is determined that eth⁃ylenediamine tetraacetic acid microcapsule inhibitor has chemical inhibition effect on coal spontaneous combustion.It can reduce the weight loss rate of coal,increase the T_(1) and T_(3) temperatures by 12℃and 34℃respectively,and greatly reduce the heat release in the range of 30-200℃and 325-683℃.The calculation of apparent activation energy shows that in P_(1) and P_(3) stages,the activation energy of inhibited coal samples is 22.96 kJ/mol and 54.98 kJ/mol respectively,which is 4.14 kJ/mol and 13.04 kJ/mol higher than that of raw coal r
作者
张嬿妮
舒盼
刘春辉
王安鹏
李乐乐
ZHANG Yanni;SHU Pan;LIU Chunhui;WANG Anpeng;LI Lele(College of Safety Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;Shaanxi Key Laboratory of Prevention and Control of Coal Fire,Xi’an University of Science and Technology,Xi’an 710054,China;Key Laboratory of Coal Resources Exploration and Comprehensive Utilization,Ministry of Land and Resources,Xi’an 710021,China)
出处
《煤炭科学技术》
CAS
CSCD
北大核心
2022年第8期108-117,共10页
Coal Science and Technology
基金
国家重点研发计划资助项目(2018YFC0807901)
国家自然科学基金资助项目(51674191)。
关键词
煤矿安全
煤自燃
乙二胺四乙酸
金属螯合剂
胶囊阻化剂
metal chelating agent
coal spontaneous combustion
characteristic temperature
heat effect
kinetic analysis
