Wang Yanming, Liu Ruijie, Li Dingrui, Zou Xiangyu, Wang Shasha, Chen Xiaoyu
State Key Laboratory of Coal Mine Disaster Prevention and Control, China University of Mining and Technology, Xuzhou 221116, China.
Intelligent Ventilation Research Center, China University of Mining and Technology, Xuzhou 221116, China.
ACS Omega. 2024 Jul 31;9(32):34608-34623. doi: 10.1021/acsomega.4c03168. eCollection 2024 Aug 13.
To guarantee the safety and sustainability of coal mining by effectively mitigating the substantial risk associated with coal spontaneous combustion, this study proposes a multifaceted prevention strategy aligned with green environmental principles. A compound flame retardant with a physicochemical control mechanism was prepared using indigenous microorganisms to mineralize residual coal after mining, utilizing as a substitute material for inorganic salts. Under laboratory conditions simulating coal self-combustion, biobased flame retardants were employed to investigate the physical and chemical transformations of heat and mass evolution from ambient temperature to combustion in two representative low-rank coals. By quantitatively comparing alterations in microbiome-based groups among raw lignite, bioretarded lignite, and two control samples, the inhibitory mechanism of biobased materials on the oxygen reaction pathway was elucidated. The findings substantiated that biobased modification can consolidate the methyl and methylene groups present in aliphatic hydrocarbon side chains, which are prone to instigating low-temperature oxidation reactions. Additionally, the preventive performance of biobased flame retardants was assessed through temperature-programmed experiments, which involved estimating the critical self-heating temperature, oxygen consumption, and gas production rates of compared coal samples. The results demonstrated significant enhancements in the resistance to spontaneous combustion following bioretarded modification. Notably, the identification grade of long flame coal shifted from easy to moderate susceptibility to spontaneous combustion. Furthermore, biobased flame retardants exhibited remarkable flame retardancy rates of approximately 80% for lignite, thereby validating their efficacy as more environmentally friendly and technologically advanced substitute materials for inhibiting spontaneous combustion in low-rank coals.
为了通过有效降低与煤炭自燃相关的重大风险来保证煤炭开采的安全性和可持续性，本研究提出了一项符合绿色环境原则的多方面预防策略。利用本地微生物制备了一种具有物理化学控制机制的复合阻燃剂，用于使开采后的残留煤矿化，将其用作无机盐的替代材料。在模拟煤炭自燃的实验室条件下，使用生物基阻燃剂研究了两种代表性低阶煤从环境温度到燃烧过程中的热质演化的物理和化学转变。通过定量比较原煤、生物阻燃煤和两个对照样品中基于微生物群落的组的变化，阐明了生物基材料对氧反应途径的抑制机制。研究结果证实，生物基改性可以巩固脂肪烃侧链中存在的甲基和亚甲基，这些基团容易引发低温氧化反应。此外，通过程序升温实验评估了生物基阻燃剂的预防性能，该实验涉及估计对比煤样的临界自热温度、氧气消耗和产气率。结果表明，生物阻燃改性后对自燃的抗性有显著提高。值得注意的是，长焰煤的鉴定等级从易自燃变为中等自燃倾向。此外，生物基阻燃剂对褐煤的阻燃率约为80%，从而验证了其作为抑制低阶煤自燃的更环保、技术更先进的替代材料的有效性。
