Jingyu Zhao , Chen Wang , Jiajia Song , Shiping Lu , Tinghao Zhang , Chi-Min Shu , Xianglei Yuan , Gang Liu
{"title":"地下煤火穿透煤体传播过程中影响气体产物释放的关键活性基团演化特征","authors":"Jingyu Zhao , Chen Wang , Jiajia Song , Shiping Lu , Tinghao Zhang , Chi-Min Shu , Xianglei Yuan , Gang Liu","doi":"10.1016/j.matchemphys.2025.131103","DOIUrl":null,"url":null,"abstract":"<div><div>The development of fissures during the process of coal spontaneous combustion (CSC) allows oxygen to continuously diffuse into deeper coal layers, thereby promoting the downward propagation of coal fires. To investigate the evolution of key active groups affecting the release of gaseous products during the propagation of CSC through a coal body, a semienclosed system was constructed to simulate the deep propagation of CSC. The concentrations of active groups in coal samples at different depths were analysed using in-situ infrared spectroscopy. Grey relational analysis was employed to quantify the correlations between the gas concentrations in different coal layers and the contents of key active groups in coal. The results indicated that, as CSC propagated deeper, the concentrations of CO, CH<sub>4</sub>, and C<sub>2</sub>H<sub>4</sub> at different coal depths increased exponentially before declining. Of all coal layers, the fourth layer had the highest heat retention, making it the layer most prone to CSC. As the coal temperature was increased, shallow coal layers primarily underwent aliphatic hydrocarbon oxidation, whereas deep coal layers exhibited intense oxidation after the ignition temperature was reached. When the coal temperature was increased from the critical temperature to the ignition temperature, the key functional groups influencing gas release gradually changed from methyl and ether groups to methylene and carbonyl groups. At high coal temperature, the cleavage reactions of carbonyl and methylene groups became the dominant sources of generated gases. Moreover, intermolecular hydrogen bonds indirectly promoted gas release by altering the pore structure of the coal body. This study can provide a new perspectives and a theoretical foundation for understanding the mechanisms of CSC disasters.</div></div>","PeriodicalId":18227,"journal":{"name":"Materials Chemistry and Physics","volume":"344 ","pages":"Article 131103"},"PeriodicalIF":4.7000,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Evolutionary characteristics of key active groups affecting the release of gaseous products during the propagation of an underground coal fire through a coal body\",\"authors\":\"Jingyu Zhao , Chen Wang , Jiajia Song , Shiping Lu , Tinghao Zhang , Chi-Min Shu , Xianglei Yuan , Gang Liu\",\"doi\":\"10.1016/j.matchemphys.2025.131103\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The development of fissures during the process of coal spontaneous combustion (CSC) allows oxygen to continuously diffuse into deeper coal layers, thereby promoting the downward propagation of coal fires. To investigate the evolution of key active groups affecting the release of gaseous products during the propagation of CSC through a coal body, a semienclosed system was constructed to simulate the deep propagation of CSC. The concentrations of active groups in coal samples at different depths were analysed using in-situ infrared spectroscopy. Grey relational analysis was employed to quantify the correlations between the gas concentrations in different coal layers and the contents of key active groups in coal. The results indicated that, as CSC propagated deeper, the concentrations of CO, CH<sub>4</sub>, and C<sub>2</sub>H<sub>4</sub> at different coal depths increased exponentially before declining. Of all coal layers, the fourth layer had the highest heat retention, making it the layer most prone to CSC. As the coal temperature was increased, shallow coal layers primarily underwent aliphatic hydrocarbon oxidation, whereas deep coal layers exhibited intense oxidation after the ignition temperature was reached. When the coal temperature was increased from the critical temperature to the ignition temperature, the key functional groups influencing gas release gradually changed from methyl and ether groups to methylene and carbonyl groups. At high coal temperature, the cleavage reactions of carbonyl and methylene groups became the dominant sources of generated gases. Moreover, intermolecular hydrogen bonds indirectly promoted gas release by altering the pore structure of the coal body. This study can provide a new perspectives and a theoretical foundation for understanding the mechanisms of CSC disasters.</div></div>\",\"PeriodicalId\":18227,\"journal\":{\"name\":\"Materials Chemistry and Physics\",\"volume\":\"344 \",\"pages\":\"Article 131103\"},\"PeriodicalIF\":4.7000,\"publicationDate\":\"2025-06-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Materials Chemistry and Physics\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0254058425007497\",\"RegionNum\":3,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATERIALS SCIENCE, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Materials Chemistry and Physics","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0254058425007497","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
Evolutionary characteristics of key active groups affecting the release of gaseous products during the propagation of an underground coal fire through a coal body
The development of fissures during the process of coal spontaneous combustion (CSC) allows oxygen to continuously diffuse into deeper coal layers, thereby promoting the downward propagation of coal fires. To investigate the evolution of key active groups affecting the release of gaseous products during the propagation of CSC through a coal body, a semienclosed system was constructed to simulate the deep propagation of CSC. The concentrations of active groups in coal samples at different depths were analysed using in-situ infrared spectroscopy. Grey relational analysis was employed to quantify the correlations between the gas concentrations in different coal layers and the contents of key active groups in coal. The results indicated that, as CSC propagated deeper, the concentrations of CO, CH4, and C2H4 at different coal depths increased exponentially before declining. Of all coal layers, the fourth layer had the highest heat retention, making it the layer most prone to CSC. As the coal temperature was increased, shallow coal layers primarily underwent aliphatic hydrocarbon oxidation, whereas deep coal layers exhibited intense oxidation after the ignition temperature was reached. When the coal temperature was increased from the critical temperature to the ignition temperature, the key functional groups influencing gas release gradually changed from methyl and ether groups to methylene and carbonyl groups. At high coal temperature, the cleavage reactions of carbonyl and methylene groups became the dominant sources of generated gases. Moreover, intermolecular hydrogen bonds indirectly promoted gas release by altering the pore structure of the coal body. This study can provide a new perspectives and a theoretical foundation for understanding the mechanisms of CSC disasters.
期刊介绍:
Materials Chemistry and Physics is devoted to short communications, full-length research papers and feature articles on interrelationships among structure, properties, processing and performance of materials. The Editors welcome manuscripts on thin films, surface and interface science, materials degradation and reliability, metallurgy, semiconductors and optoelectronic materials, fine ceramics, magnetics, superconductors, specialty polymers, nano-materials and composite materials.