草本沼泽泥炭加水热解产物烃类气体氢同位素特征  

Study on hydrogen isotopes of hydrocarbon gases generated during hydrous pyrolysis of herbaceous marsh peat

作　　者：段毅 吴应忠[1,3] 赵阳 曹喜喜[5] 马兰花 Duan yi1,2,3,Wu Ying-zhong1,3 ,Zhao Yang4,Cao Xi-xi5 ,Ma Lan-hua6(1.Gansu Provincial Key Laboratory of Petroleum Resources;Key Laboratory of Petroleum Resources Research Northwest Institute of Eco Environment and Resources ,Chinese Academy of Sciences , Lanzhou 730000 ,China 2.School of Earth Science ＆ Resources ,Chang ＇an University ,Xi＇an 710054 ,China 3.University of Chinese Academy of Sciences ,Beijing 100049 ,China ; 4.College of Petroleum Engineering ,Liaoning Shihua University ,Eushun 113001 ,China 5.Admissions Office , Lanzhou University, Lanzhou 730000, China ; 6.Earthquahe Research Institute of Lanzhou ,SSB ,Lanzhou 730000 ,China)

机构地区：[1]甘肃省油气资源研究重点实验室(中国科学院西北生态环境资源研究院)中国科学院油气资源研究重点实验室,甘肃兰州730000 [2]长安大学地球科学与资源学院,陕西西安710054 [3]中国科学院大学,北京100049 [4]辽宁石油化工大学石油与天然气工程学院,辽宁抚顺113001 [5]兰州大学招生办公室,甘肃兰州730000 [6]国家地震局兰州地震研究所,甘肃兰州730000

出　　处：《天然气地球科学》2018年第3期305-310,共6页Natural Gas Geoscience

基　　金：国家自然科学基金项目(编号:41472121;41772108;41272125)联合资助

摘　　要：为了认识成岩水介质对热解煤层气氢同位素的影响,对草本泥炭进行了加水和无水热解模拟实验,研究了热解产物烃类气体的氢同位素组成及其差异性与演化规律,发现成岩水介质对热成因烃类气体氢同位素组成具有显著的影响。在泥炭中加入氢同位素值高于泥炭形成环境水的水,其模拟实验产生的烃类气体氢同位素值显著增高;并且从泥炭连续热解至RO值为5.5%时,加水泥炭模拟实验使热解甲烷、乙烷和丙烷平均δD值分别增加了74‰、42‰和66‰。随着模拟温度升高,生成的烃类气体的δD值增大。认为加水模拟实验使热解烃类气体氢同位素值增高起因于水氢与有机氢同位素的交换。建立了具有较高δD值的淡水参与下热解烃类气体δD值与RO值的数学模型,以及不同烃类气体之间δD值的数学模型。这些研究成果为成岩水介质参与下草本沼泽成煤物质热解煤层气的成因研究提供了科学依据。In order to understand the influence of diagenetic water medium on the isotopic compositions of thermogenic coalbed gas, hydrous and anhydrous pyrolysis experiments were performed on herbaceous marsh peat.We studied the hydrogen isotopic compositions, their differences and evolutionary law of hydro- carbon gases generated during the pyrolysis of the samples.It was found that the diagenetic water medium has a significant effect on the hydrogen isotopic composition of the hydrocarbon gases. Adding water with higher hydrogen isotopic value than peat-formed environmental water,the hydrocarbon isotope value of the hydrocarbon gas produced by peat pyrolysis was significantly higher.At pyrolysis intervals from peat to vit rinite reflectance values （Ro） of 5.5%,the average 3D values of pyrolytic methane, ethane and propane produced by hydrous peat pyrolysis experiment increased by 74‰,42‰ and 66‰ ,respectively.As the simulated temperature increased,the 3D value of the generated hydrocarbon gas increased.It was considered that higher hydrogen isotope value of hydrocarbon gas produced by hydrous peat pyrolysis experiment resulted from the isotope exchange between water hydrogen and organic hydrogen. The relationships between Ro values and the hydrogen isotopic compositions of the hydrocarbon gases generated by hydrous peat pyrolysis and the hydrogen isotopic relationship between the hydrocarbon gases were established. These results may provide a basis for studying on the genesis of coalbed gas formed by herbaceous marsh coal-forming material with the participation of diagenetic water media.

关 键 词：模拟实验 烃类气体 氢同位素 成岩水介质 影响因素 

分 类 号：TE122.113[石油与天然气工程—油气勘探]