Effect of gas on microstructure and thermal reactivity of coal during low temperature oxidation
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摘要:
为研究瓦斯气氛下煤低温氧化过程中微观理化特性及宏观煤氧复合热效应，选择不同变质煤及二次氧化煤样作为研究对象，利用傅里叶红外光谱仪和C80微量量热仪，研究在不同瓦斯气氛下煤低温氧化过程物理化学结构特性、动力学参数、热效应等变化特征。通过分析不同瓦斯气氛下煤自燃氧化过程中微观结构以及宏观放热特性，明确瓦斯对煤氧化特性的最终影响。结果表明：瓦斯通过抑制煤低温氧化过程中关键活性基团相对含量，延缓煤低温氧化进程，4%瓦斯具有最为明显的抑制效果，其对4种活性基团的抑制程度为：含氧官能团 (66.5%) > 芳香烃 (47.0%) >脂肪烃 (29.7%) >羟基 (24.7%)。在快速放热阶段，由于煤对瓦斯分子的吸附能力较大，瓦斯气体占据煤分子中的吸附位点，阻碍了煤氧复合反应进程，导致放热效应受到瓦斯抑制；同时瓦斯含量显著影响煤氧复合进程活化能的大小。对于较高变质程度的不黏煤、瘦煤和无烟煤，瓦斯对其低温氧化反应的抑制作用较为显著；对较低变质程度的长焰煤影响较小。对于二次氧化煤样，瓦斯对于煤样的抑制作用随着瓦斯含量的增加而增强，而瓦斯对一次氧化煤样的影响随变质程度降低而减弱，且瓦斯含量2%时的抑制程度强于4%。研究结果对防治瓦斯与煤自燃耦合致灾事故的理论研究有重要意义。
Abstract:In order to investigate the microscopic physicochemical properties and macroscopic coal-oxygen complex thermal effects in the low-temperature oxidation of coal under gas atmosphere, different metamorphic coal and secondary oxidized coal samples as research objects were selected in this paper. Fourier infrared spectrometer and C80 microcalorimeter were employed to study the changes of physicochemical structural properties, kinetic parameters and thermal effects in the low-temperature oxidation of coal under different gas atmospheres. By analysing the microstructure and macroscopic exothermic characteristics of different gas content during coal spontaneous oxidation, the ultimate influence of gas on the oxidation characteristics of coal was clarified. The results show that gas delays the low-temperature oxidation process of coal by inhibiting the relative content of key active groups in the low-temperature oxidation process of coal. 4% gas has the most obvious inhibitory effect. The degree of inhibition on the four active groups is: oxygen-containing functional groups (66.5%) > Aromatic hydrocarbons (47.0%) > Aliphatic hydrocarbons (29.7%) > Hydroxyl (24.7%). In the rapid exothermic stage, due to the large adsorption capacity of coal to gas molecules, gas occupies the adsorption sites in coal molecules, which hinders the process of coal-oxygen recombination reaction, resulting in the exothermic effect being suppressed by gas; at the same time, gas content significantly affects coal oxygen. The amount of activation energy required for the recombination process. For high metamorphic non-stick coal, lean coal and anthracite, gas has a more significant inhibitory effect on its low temperature oxidation reaction; it has less effect on low metamorphic long flame coal. For secondary oxidized coal samples, the inhibitory effect of gas on coal samples increases with the increase of gas content, while the effect of gas on primary oxidized coal samples decreases as the degree of metamorphism decreases, and the degree of inhibition when the gas content is 2% is stronger than 4%. The results of the work have great significance to the theoretical study of the prevention and control of the coupling of gas and coal spontaneous combustion causing accidents.
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Keywords:
- spontaneous coal combustion /
- gas /
- microstructure /
- thermal effect /
- activation energy /
- low-temperature oxidation
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图 1 不同瓦斯含量及温度下长焰煤红外谱图
Figure 1. Infrared spectra of long flame coal with different gas content and temperature
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图 3 长焰煤4类活性基团相对含量变化特征
Figure 3. Change characteristics of relative content of four types of active groups in long flame coal
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图 4 不同瓦斯含量气氛下瘦煤的热流曲线
Figure 4. Heat flow curves of lean coal under different gas content atmospheres
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图 5 不同瓦斯体积分数下瘦煤煤样的HF及DHF曲线
Figure 5. HF and DHF curves of lean coal sample under different gas concentrations
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图 6 不同瓦斯体积分数下瘦煤放热量与温度变化曲线
Figure 6. Variation curves of heat release and temperature of lean coal under different gas concentrations
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图 7 不同瓦斯体积分数下4种煤样的总放热量
Figure 7. Total heat release value of four coal samples under different gas concentrations
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图 8 不同瓦斯体积分数下瘦煤的ln((dH/dt)/ΔHM0)与1/T拟合
Figure 8. Fitting of ln((dH/dt)/ΔHM0) with 1/T of coal samples under different gas concentrations
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图 9 不同瓦斯体积分数下煤样的活化能
Figure 9. Activation energy of coal samples under different gas concentrations
表 1 煤质分析
Table 1 Coal quality analysis
煤样 工业分析/% 元素分析/% 元素含量 Mad Aad Vad FCad Cdaf Hdaf Ndaf Odaf w(O)∶w(C) w(H)∶w(C) 长焰煤 7.22 11.71 30.56 50.51 74.05 3.97 1.41 20.57 0.28 0.054 不粘煤 7.43 8.44 29.76 54.37 75.72 3.91 1.48 18.89 0.25 0.052 瘦煤 0.84 13.98 13.58 71.60 79.94 3.07 2.20 14.79 0.19 0.038 无烟煤 1.77 10.21 8.05 79.97 82.94 2.32 1.24 13.5 0.16 0.028 
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表 2 煤中主要活性基团的波峰归属
Table 2 The peak assignments of the main active groups in coal
吸收峰类型 谱峰位置/cm−1 官能团 谱峰归属 羟基 3 660~3 632 —OH 游离的羟基 3 550~3 200 —OH 分子间缔合的氢键、酚羟基、
醇羟基或氨基含氧官能团 1 736~1 722 C=O 酯类的羰基伸缩振动 1 330~1 060 C—O—C 脂肪醚伸缩振动 脂肪烃 2 975~2 915 —CH3 甲基不对称伸缩振动 2 875~2 858 —CH2 亚甲基不对称伸缩振动 1 449~1 439 —CH2 亚甲基剪切振动 1 380~1 370 —CH3 甲基剪切振动 芳香烃 3 160~3 032 Ar—CH 芳香环中C–H的伸缩振动 1 604~1 599 C=C 芳香环中C=C的伸缩振动 900~700 Ar—CH 多种取代苯的变形振动
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[1] CHEN X,LI L,WANG L,et al. The current situation and prevention and control countermeasures for typical dynamic disasters in kilometer-deep mines in China[J]. Safety Science,2019,115:229−236. doi: 10.1016/j.ssci.2019.02.010
[2] ZHANG Q,YAO B Y,LI Y H,et al. Research progress and prospect on the monitoring and early warning and mitigation technology of meteorological drought disaster in northwest China[J]. Advances in Earth Science,2015,30(2):196.
[3] WANG H Y,CHENG C F,CHENG C. Characteristics of polycyclic aromatic hydrocarbon release during spontaneous combustion of coal and gangue in the same coal seam[J]. Journal of Loss Prevention in the Process Industries,2018,55:392−399. doi: 10.1016/j.jlp.2018.07.004
[4] WANG C J,YANG S Q,LI X W. Simulation of the hazard arising from the coupling of gas explosions and spontaneously combustible coal due to the gas drainage of a gob[J]. Process Safety and Environmental Protection,2018,118:296−306. doi: 10.1016/j.psep.2018.06.028
[5] 王德明,邵振鲁,朱云飞. 煤矿热动力重大灾害中的几个科学问题[J]. 煤炭学报,2021,46(1):57−64. WANG Deming,SHAO Zhenlu,ZHU Yunfei,et al. Several scientific issues in major thermal disasters in coal mines[J]. Journal of China Coal Society,2021,46(1):57−64.
[6] ZHENG Y N,LI Q Z,ZHU P F,et al. Study on multi-field evolution and influencing factors of coal spontaneous combustion in goaf[J]. Combustion Science and Technology,2021,195(2):247−264.
[7] TANG Z Q,YANG S Q,XU G,et al. Disaster-causing mechanism and risk area classification method for composite disasters of gas explosion and coal spontaneous combustion in deep coal mining with narrow coal pillars[J]. Process Safety and Environmental Protection,2019,132:182−188. doi: 10.1016/j.psep.2019.09.036
[8] 林柏泉,李庆钊,周 延. 煤矿采空区瓦斯与煤自燃复合热动力灾害多场演化研究进展[J]. 煤炭学报,2021,46(6):1715−1726. LIN Baiquan,LI Qinzhao,ZHOU Yan. Research progress on multi-field evolution of combined thermal and dynamic disasters of gas and coal spontaneous combustion in coal mine goaf[J]. Journal of China Coal Society,2021,46(6):1715−1726.
[9] WANG G,XIE J,XUE S. Laboratory study on low-temperature coal spontaneous combustion in the air of reduced oxygen and low methane concentration[J]. Technical Gazette,2015,22(5):1319−1325.
[10] 邓 军,李 鹏,程文东,等. 瓦斯对煤自燃特性参数影响的实验研究[J]. 煤矿安全,2014,45(11):31−33. DENG Jun,LI Peng,CHENG Wendong,et al. Experimental study on the influence of gas on coal spontaneous combustion characteristic parameters[J]. Safety in Coal Mines,2014,45(11):31−33.
[11] WANG H Y,TIAN Y,LI J L,et al. Experimental study on thermal effect and gas release laws of coal-polyurethane cooperative spontaneous combustion[J]. Scientific Reports,2021,11(1):1−13. doi: 10.1038/s41598-020-79139-8
[12] ZHOU F,LIU S,PANG Y,et al. Effects of coal functional groups on adsorption microheat of coal bed methane[J]. Energy & Fuels,2015,29(3):1550−1557.
[13] HU Y,WANG S,HE Y. Investigation of the coal oxidation effect on competitive adsorption characteristics of CO2/CH4[J]. Energy & Fuels,2020,34(10):12860−12869.
[14] TANG Y,WANG H. Experimental investigation on microstructure evolution and spontaneous combustion properties of secondary oxidation of lignite[J]. Process Safety and Environmental Protection,2019,124:143−150. doi: 10.1016/j.psep.2019.01.031
[15] 汤宗情. 煤自燃过程中孔隙演化机制及其对多元气体吸附特性的影响[D]. 徐州: 中国矿业大学, 2020. TANG Zongqing. Pore evolution mechanism during coal spontaneous combustion and its influence on multi-component gas adsorption characteristics [D]. Xuzhou: China University of Mining and Technology, 2020.
[16] 白亚娥. 不同预氧化程度煤二次氧化特性研究[D]. 西安: 西安科技大学, 2017. BAI Ya’e. Study on the secondary oxidation characteristics of coal with different pre-oxidation degrees [D]. Xi'an: Xi'an University of Science and Technology, 2017.
[17] 姜 峰,尚芳兰,李珍宝,等. 热重–FTIR法分析不粘煤氧化特性参数[J]. 燃烧科学与技术,2021,27(1):35−42. JIANG Feng,SHANG Fanglan,LI Zhenbao,et al. Analysis of non-stick coal oxidation characteristics by thermogravimetric-FTIR method[J]. Combustion Science and Technology,2021,27(1):35−42.
[18] 许 芹. 氧化煤表面吸氧能力演化及分子活性结构二次氧化特性研究[D]. 徐州: 中国矿业大学, 2021. XU Qin. The evolution of oxygen absorption capacity on the surface of oxidized coal and the secondary oxidation characteristics of molecular active structures [D]. Xuzhou: China University of Mining and Technology, 2021.
[19] 冯 杰,李文英,谢克昌. 傅立叶红外光谱法对煤结构的研究[J]. 中国矿业大学学报,2002(5):25−29. FENG J,LI W Y,XIE K C. Study on coal structure by Fourier transform infrared spectroscopy[J]. Journal of China University of Mining and Technology,2002(5):25−29.
[20] 王 坤. 煤氧化产物产热及官能团变化特性研究[D]. 北京: 煤炭科学研究总院, 2016. WANG Kun. Study on heat generation and functional group change characteristics of coal oxidation products [D]. Beijing: General Coal Research Institute, 2016.
[21] QI G S,WANG D M,ZHENG K M,et al. Kinetics characteristics of coal low-temperature oxidation in oxygen-depleted air[J]. Journal of Loss Prevention in the Process Industries,2015,35:224−231. doi: 10.1016/j.jlp.2015.05.011
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