高硫易燃矸石山堆积体自燃机理与阻燃机制

Spontaneous combustion of inflammable high-sulfur coal waste rock pile is a main serious hazard in coal mining industry. This study aims to reveal self-heating reactions and the flame retardant mechanism of this phenomenon..Due to complicated compositions and structures of high-sulfur coal and waste rock, the applicant proposes to study the mechanism through researching on elementary structure units. Firstly, chemical structure units with high reactivity will be identified from the complicated coal structure for better explaining the combustion mechanism on micro-level. Chain length of groups and distribution of branched and bridge bond will be analyzed through the UWE, in-situ FTIR and NMR. Variables and quantitative distribution of functional groups will be obtained. Unit groups of aliphatic hydrocarbons, oxygen functional groups and radicals will be identified after analyzing their active sites and bond dissociation energy. Charge accumulation and frontier orbitals of functional groups will be acquired based on the quantum chemistry. Oxygen consumption, products and self-heating correlation during spontaneous combustion will be studied using a comprehensive testing equipment. Micro heat effect during low-temperature oxidation will be tested using C80 calorimeter. Based on comprehensive analysis, key active groups that influence the development of coal self-heating and their reaction sequences will be revealed..Based on the investigations above, the applicant will study chemical ways for inhibiting the reactions of these reaction sequences. Multi parameters will be analyzed, e.g. flame retardant mechanism, inhibiting effect and influencing factors. On this basis, the applicant will propose a novel efficient chemical inhibitor. Using antioxidants, hydroxyl compounds and functional additives, a high-effective chemical inhibitor which can restrain or cut off the reaction sequences of key active groups will be invented to prevent spontaneous combustion..In application of the inhibitor, it will be sent to the self-ignition region by temperature-sensitive gel suspension. They will maintain as their original status until coal temperature reach a specific range. In response to coal temperature and its changing trend, water, chemical inhibitors and the temperature-sensitive gel will realize inhibition simultaneously or step-by-step, thus improving the inhibition efficiency. For more effective application, the project will study the flowing characteristics of inhibitor in different fluid carriers. Then the best technical parameters will be selected, including additive quantity of inhibitor, the rate and pressure of flow..This study is helpful for further understanding the self-heating reaction and flame retardant mechanism of the spontaneous combustion of inflammable high-sulfur coal waste rock pile. The results will provide theoretical basis and key technology for more effective prevention of this hazard.

针对高硫煤和含高硫煤矸石的组成及结构复杂的特点，基于多元测试结果将其复杂自燃机理分解成基本结构单元开展研究，提出其中易发生反应的基本结构单元群，以模型化合物为桥梁，根据量子化学计算和综合测试结果推导活性结构单元的基元反应序列及链式反应模型，阐明自燃过程的关键活性基团种类及演变过程；研究不同化学阻燃方法对关键活性基团的作用条件及阻燃机制，分析化学阻燃过程的惰化效果及影响因素；通过多剂联用、复配优化，研制基于抗氧化剂、功能性化合物和添加剂复配物的化学阻化剂，消除或抑制煤中关键活性结构及反应中间体实现自燃防治；使用过程中，以温敏性超高水封堵浆体为载体将其输送至自燃区域，根据该区域温度状态，混合浆体中的水、温敏浆体、化学阻燃材料可同步或逐级发挥阻燃作用，从而提高阻燃效率并延长阻燃周期。通过研究，阐明高硫煤矸石山自燃机理并掌握其阻燃机制，为该类灾害的高效防治提供基础。

煤矸石山自燃是威胁矿山安全和生态环境的主要自然灾害之一。我国现有煤矸石山近两千座，占地约1.5万公顷，其中约三分之一正在自燃或曾发生过自燃。煤矸石山自燃产生的有毒有害气体、烟尘及燃烧残留物对当地生态和人员健康构成严重威胁。高硫煤自燃发生发展及其诱发煤矸石山自燃的机制是煤矸石山自燃高效防治的基础。本项目针对高硫煤和含高硫煤矸石的组成及结构复杂的特点，基于多元测试结果将其复杂自燃机理分解成基本结构单元开展研究，提出了其中易发生反应的基本结构单元群，以模型化合物为桥梁，分析得到了不同结构单元的电荷积聚和前线轨道组成，并定量分析了活性部位及前线轨道的反应特征。根据量子化学计算和综合测试结果推导出了活性结构单元的基元反应序列及链式反应模型，阐明了高硫煤矸石自燃过程的关键活性基团种类及演变过程。研究了不同化学阻燃方法对关键活性基团的作用条件、阻燃机制、惰化效果及影响因素，分析了化学阻燃过程的惰化效果及影响因素；在研发单组分和简单复配型化学阻化剂的基础上，通过多剂联用、复配优化，研制了基于抗氧化剂、功能性化合物和添加剂复配物的化学阻化剂，消除或抑制煤中关键活性结构及反应中间体实现自燃防治，分析了阻化前后自燃过程的表面活性基团、自由基浓度、耗氧、产热产物、临界温度、自燃倾向性和自然发火时间等特性差异。使用过程中，以温敏性超高水封堵浆体为载体将其输送至自燃区域，根据该区域温度状态，混合浆体中的水、温敏浆体、化学阻燃材料可同步或逐级发挥阻燃作用，从而提高了阻燃效率并延长阻燃周期。采用实验室已构建的防灭火材料灌注模拟装置及综合测试系统，研究了阻化剂在温敏性超高水封堵浆体中的流动规律，分析阻化剂添加比例、阻化剂混合浆体流量、管内浆体压力等输送参数对阻化剂浆体流动特性的影响，为现场推广应用提供了基础参数。通过本项目研究，阐明了高硫煤矸石山自燃机理并掌握其阻燃机制，为该类灾害的高效防治提供基础。