【摘要】 本文运用热解技术对采自准噶尔盆地风城地区6个重度生物降解稠油进行沥青质热解实验。通过分析沥青质热解产物中生物标志化合物组成和单体正构烷烃碳同位素组成,探索其在降解稠油油源研究中的应用。研究结果显示,沥青质热解产物中生物标志化合物组成特征易受热解温度的影响,指示母质沉积水体环境的参数Pr/Ph比值随热解温度升高逐渐增大,在较高的温度下,高碳数、高环数的生物标志化合物易裂解生成低碳数、低环数的化合物,导致C₂₀三环萜烷/C₃₀藿烷和孕甾烷/αααC₂₉R甾烷两个参数的比值随热解温度升高逐渐增大,表明利用沥青质热解产物生物标志化合物组成进行降解稠油油源判识易出现偏差。而沥青质热解产物单体正构烷烃碳同位素组成随热解温度升高并没有明显的变化,6个降解稠油沥青质热解产物单体正构烷烃碳同位素分布曲线呈水平分布,与来自风城组烃源岩的典型原油基本相似,说明沥青质热解产物中单体烃碳同位素组成特征可用于重度降解稠油油源分析。另外,通过对比稠油与其沥青质热解产物中单体正构烷烃单体碳同位素组成差异,可用于研究多油源以及后期混入的问题。更多还原

【Abstract】 This research performed pyrolysis on the asphaltenes of six biodegraded heavy oils from the Fengcheng area of the Junggar Basin to investigate the biomarker and carbon isotopic compositions of individual n-alkanes in the asphaltene pyrolysis products and their application in the study of biodegaraeded oil source correlations.The results showed that the biomarker composition in the asphaltene pyrolysis products was susceptible to the pyrolysis temperature.The Pr/Ph value which indicates the sedimentary water environment,increases with the rise of pyrolysis temperature.The high carbon number and high ring number biomarkers,which made the C₂₀ tricyclic terpane/C₃₀ hopane value and the pregnant sterane/αααC₂₉R sterane value increase with the pyrolysis temperature increase.Using the biomarker composition of the asphaltene pyrolysis products in a biodegraded heavy oil source correlation study will produce a deviation.No significant change in the carbon isotopic composition of individua n-alkanes in the asphaltene pyrolysis products was observed with the pyrolysis temperature increase.Moreover the distribution curves of the carbon isotopes of the n-alkanes in the asphaltene pyrolysis products from six biodegraded heavy oils were in a horizontal position similar to the typical crude oil from the source rocks of the Fengcheng formation.The carbon isotopic composition of individual n-alkanes in the asphaltene pyrolysis products can be used for the biodegraded heavy oil source correlation study.A comparison of the carbon isotopic composition of the n-alkanes in the biodegraded heavy oil and its asphaltene pyrolysis products can also be used to study the differentiated varieties of oil source and input.更多还原