高煤级煤岩流变作用的谱学研究  

Spectrum Research on Rheology of High Rank Coal

作　　者：于立业[1] 琚宜文[1] 李小诗[1] 

机构地区：[1]中国科学院计算地球动力学重点实验室,中国科学院大学地球科学学院,北京100049

出　　处：《光谱学与光谱分析》2015年第4期899-904,共6页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(40972131,41372213,41030422);中国科学院战略性先导科技专项课题(XDA05030100)资助

摘　　要：为研究高煤级煤岩在不同流变条件下大分子结构的变化特征,对沁水盆地南部高煤级原生结构煤岩及其变温变压流变实验后的煤岩进行了FTIR和激光拉曼光谱测试和分析。结果表明：不同温压条件形成的不同类型流变煤岩的大分子结构和组成具有明显的差别。煤岩变温变压流变实验（温度300~400℃、围压50~100 MPa、应变小于10%和应变速率10^-4~10-7·s^-1）会使其大分子结构产生改变,并实现化学结构重组：当温度为300或350℃,高煤级煤岩易形成脆性流变或脆韧性流变,机械能转化为热能,一些键能较弱的支链和官能团断裂并且结构脱落,产生裂解小分子,其过程以应力降解作用为主,而芳香结构增多,同时出现应力缩聚;而温度上升至400℃以上,高煤级煤岩即可发生韧性流变,次生缺陷发育,机械能转化为应变能,脱落的小分子优先嵌入或吸附在大分子结构的缺陷或表面,脂肪和芳香结构的变化,其过程既有应力降解作用又有应力缩聚作用,而且以应力缩聚作用为主;围压和样品注水状态对大分子结构影响不明显。Aiming to discuss the change characteristic of macromolecular structures of high rank coal in different rheological con‐ditions ,the high rank undeformed coal from southern Qinshui basin and the coal after variable temperature and variable pressure rheology experiments were investigated and analyzed in detail through Fourier transform infrared spectroscopy （FTIR） and laser Raman spectra analysis .The result shows that the texture and composition of different types of rheological coals under different＆amp;nbsp;temperature and pressure exhibit significant differences .Experiments of variable temperature and pressure of high rank coal （temperature ：300~400 ℃ ,confining pressure ：50~100 MPa ,strain ：less than 10% and strain rate ：10^-4 ~10^-7 ·s^-1 ） will distort their macromolecular structures and recombine the chemistry structures .When the temperature is 300 ℃ or 350 ℃ ,the high rank coal generates brittle or brittle‐ductile rheology easily ,mechanical energy transforms to heat energy ,some branches and functional groups with weaker bond energy break and fall off ,which split as dissociative micromolecule ,with stress degrada‐tion as principal role ,and stress polycondensation occurs with aromatic texture increasing .When the temperature is up to 400℃ ,ductile rheology of the high rank coal occurs with the secondary defects increasing ,mechanical energy transforms to strain energy which helps the early shedding small molecules be embedded or adsorbed in the defect or on the surface of macromolecular preferentially and change the aliphatic and aromatic structures .It is affected by stress degradation and polycondensation pro‐gress ,and the latter is dominated .The confining pressure and water injection of coal do not have much effect on the macromolec‐ular structure obviously .

关 键 词：高煤级煤岩 煤岩流变 大分子结构 傅里叶变换红外光谱 激光拉曼光谱 

分 类 号：O657.3[理学—分析化学]