In order to uncover the intrinsic reasons for spontaneous combustion of sulfide minerals,representative samples were collected from typical metal mines to carry out the mechanical activation experiment.The structures ...In order to uncover the intrinsic reasons for spontaneous combustion of sulfide minerals,representative samples were collected from typical metal mines to carry out the mechanical activation experiment.The structures and heat behaviors of activated samples were characterized by scanning electron microscopy（SEM）,X-ray diffraction（XRD） analysis,and simultaneous thermal analysis（STA）.It is found that the sulfide minerals after mechanical activation show many changes with increased specific surface areas,aggregation phenomenon,decreased diffraction peak intensity,broadened diffraction peak,declined initial temperatures of heat release and self-ignition points.A new theory for explaining the spontaneous combustion of sulfide minerals is put forward：the chemical reaction activity of sulfide minerals is heightened by all kinds of mechanical forces during the mining,and the spontaneous combustion takes place finally under proper environment.展开更多
The combustion characteristics of two kinds of unburned pulverized coal (UPC) made from bituminous coal and anthracite were investigated by thermogravimetric analysis under air. The reaction kinetics mechanisms betwee...The combustion characteristics of two kinds of unburned pulverized coal (UPC) made from bituminous coal and anthracite were investigated by thermogravimetric analysis under air. The reaction kinetics mechanisms between UPC and CO2 in an isothermal experiment in the temperature range 1000–1100°C were investigated. The combustion performance of unburned pulverized coal made from bituminous coal (BUPC) was better than that of unburned pulverized coal made from anthracite (AUPC). The combustion characteristic indexes (S) of BUPC and AUPC are 0.47 × 10^-6 and 0.34 × 10^-6 %2·min^-2·°C^-3, respectively, and the combustion reaction apparent activation energies are 91.94 and 102.63 kJ·mol^-1, respectively. The reaction mechanism of BUPC with CO2 is random nucleation and growth, and the apparent activation energy is 96.24 kJ·mol^-1. By contrast, the reaction mechanism of AUPC with CO2 follows the shrinkage spherical function model and the apparent activation energy is 133.55 kJ·mol^-1.展开更多
Discussed latest research results of basic theory research of coal spontaneous combustion in detail,with quantum chemical theory and method and experiment syste- matically studied chemical structure of coal molecule,a...Discussed latest research results of basic theory research of coal spontaneous combustion in detail,with quantum chemical theory and method and experiment syste- matically studied chemical structure of coal molecule,adsorption mechanism of coal sur- face to oxygen molecule and chemical reaction mechanism and process of spontaneous combustion of organic macromolecule and low molecular weight compound in coal from microcosmic view,and established complete theoretical system of the mechanism of coal spontaneous combustion.展开更多
为揭示FeS引起油气储罐和炼油设备着火、爆炸事故的机制,以防治FeS自燃,分析活性FeS氧化发火特性,构建自燃反应表观动力学模型。首先,利用差热天平测定室温时样品放热变化及热重变化,分析样品自燃发火倾向性及化学反应机制;然后,研究氧...为揭示FeS引起油气储罐和炼油设备着火、爆炸事故的机制,以防治FeS自燃,分析活性FeS氧化发火特性,构建自燃反应表观动力学模型。首先,利用差热天平测定室温时样品放热变化及热重变化,分析样品自燃发火倾向性及化学反应机制;然后,研究氧气及空气气氛对FeS自燃反应的影响。首次通过试验证实,活性FeS在室温时即可与纯氧气或空气中的氧快速反应并释放大量热,且极易自燃;首次利用FWO法开展FeS室温下自燃反应表观动力学研究。研究结果表明:活性FeS样品在氧气中的自燃反应主要产物为Fe_2O_3,Fe_2(SO_4)_3和SO_2,表观活化能为57.101 k J/mol;在空气中的自燃反应主要产物为Fe_2O_3,S和SO_2,表观活化能为89.471 k J/mol。展开更多
基金Project(2012J05088) supported by the Natural Science Foundation of Fujian Province,ChinaProject(022409) supported by the School Talent Foundation of Fuzhou University,China
文摘In order to uncover the intrinsic reasons for spontaneous combustion of sulfide minerals,representative samples were collected from typical metal mines to carry out the mechanical activation experiment.The structures and heat behaviors of activated samples were characterized by scanning electron microscopy（SEM）,X-ray diffraction（XRD） analysis,and simultaneous thermal analysis（STA）.It is found that the sulfide minerals after mechanical activation show many changes with increased specific surface areas,aggregation phenomenon,decreased diffraction peak intensity,broadened diffraction peak,declined initial temperatures of heat release and self-ignition points.A new theory for explaining the spontaneous combustion of sulfide minerals is put forward：the chemical reaction activity of sulfide minerals is heightened by all kinds of mechanical forces during the mining,and the spontaneous combustion takes place finally under proper environment.
基金financially supported by the National Natural Science Foundation of China (Nos. 51874080, 51604069, and 51774071)the Fundamental Research Funds for the Central Universities, China (No. N162504004)
文摘The combustion characteristics of two kinds of unburned pulverized coal (UPC) made from bituminous coal and anthracite were investigated by thermogravimetric analysis under air. The reaction kinetics mechanisms between UPC and CO2 in an isothermal experiment in the temperature range 1000–1100°C were investigated. The combustion performance of unburned pulverized coal made from bituminous coal (BUPC) was better than that of unburned pulverized coal made from anthracite (AUPC). The combustion characteristic indexes (S) of BUPC and AUPC are 0.47 × 10^-6 and 0.34 × 10^-6 %2·min^-2·°C^-3, respectively, and the combustion reaction apparent activation energies are 91.94 and 102.63 kJ·mol^-1, respectively. The reaction mechanism of BUPC with CO2 is random nucleation and growth, and the apparent activation energy is 96.24 kJ·mol^-1. By contrast, the reaction mechanism of AUPC with CO2 follows the shrinkage spherical function model and the apparent activation energy is 133.55 kJ·mol^-1.
基金National Natural Science Foundation(50474010)Eleventh Five Year Key Technologies(2006BAK03B05)
文摘Discussed latest research results of basic theory research of coal spontaneous combustion in detail,with quantum chemical theory and method and experiment syste- matically studied chemical structure of coal molecule,adsorption mechanism of coal sur- face to oxygen molecule and chemical reaction mechanism and process of spontaneous combustion of organic macromolecule and low molecular weight compound in coal from microcosmic view,and established complete theoretical system of the mechanism of coal spontaneous combustion.
文摘为揭示FeS引起油气储罐和炼油设备着火、爆炸事故的机制,以防治FeS自燃,分析活性FeS氧化发火特性,构建自燃反应表观动力学模型。首先,利用差热天平测定室温时样品放热变化及热重变化,分析样品自燃发火倾向性及化学反应机制;然后,研究氧气及空气气氛对FeS自燃反应的影响。首次通过试验证实,活性FeS在室温时即可与纯氧气或空气中的氧快速反应并释放大量热,且极易自燃;首次利用FWO法开展FeS室温下自燃反应表观动力学研究。研究结果表明:活性FeS样品在氧气中的自燃反应主要产物为Fe_2O_3,Fe_2(SO_4)_3和SO_2,表观活化能为57.101 k J/mol;在空气中的自燃反应主要产物为Fe_2O_3,S和SO_2,表观活化能为89.471 k J/mol。
