原油裂解过程中组分演化模型及金刚烷类化合物的地球化学特征
|
摘要
以塔里木盆地塔中169井中质原油为研究对象,采用黄金管—高压釜热模拟方法,揭示了原油裂解气、液、固三相裂解产物随热成熟度的转化规律,并明确了裂解过程中金刚烷类化合物的演化特征。结果表明,原油裂解过程中烷烃消失、稠环芳烃聚合物不断生成,高分子烃类逐渐裂解为低分子烃类与焦沥青。裂解过程中金刚烷类化合物的形成演化可以分为稳定阶段(Easy%R_O<1.5%)、生成阶段(Easy%R_O=1.5%~2.8%)和裂解阶段(Easy%R_O>2.8%)3个重要阶段。基于各阶段气、液、固三相产物的相对浓度初次建立了原油主要组分热演化的定量模型。研究深化了对原油裂解过程的认识,所获认识为评价塔里木盆地塔中地区原油的热稳定性、预测油气保存深度下限提供了理论依据。
This study employed a gold tube-autoclave reactor system to investigate the thermal cracking of crude oil sample from Well Tazhong 169 and the geochemical evolution of carbon isotope and diamondoids during oil cracking.Our results indicated that oil cracking is a process accompanied by the decline of aliphatics and raise aromatics,also a process featuring the large molecular hydrocarbons transformed into small molecular hydrocarbons and pyrobitumen.The evolution of diamondoids can be divided into three stages,i.e.,stable stage(Easy%R_O<1.5%),formation stage(Easy%R_O=1.5%-2.8%)and diminution stage(Easy%R_O>2.8%).A quantitative kinetic model of compositional evolution of pyrolysates has been established for each stage.The models are instructive for the gas composition characteristics prediction and resource evaluation of ancient reservoirs.The present study improves our understanding on the geochemical characteristics associated with oil cracking processes,and the findings provide solid supports for the evaluation of the thermal stability and the prediction of preservation deadline of oil in Tazhong area in the Tarim Basin.
This study employed a gold tube-autoclave reactor system to investigate the thermal cracking of crude oil sample from Well Tazhong 169 and the geochemical evolution of carbon isotope and diamondoids during oil cracking.Our results indicated that oil cracking is a process accompanied by the decline of aliphatics and raise aromatics,also a process featuring the large molecular hydrocarbons transformed into small molecular hydrocarbons and pyrobitumen.The evolution of diamondoids can be divided into three stages,i.e.,stable stage(Easy%R_O<1.5%),formation stage(Easy%R_O=1.5%-2.8%)and diminution stage(Easy%R_O>2.8%).A quantitative kinetic model of compositional evolution of pyrolysates has been established for each stage.The models are instructive for the gas composition characteristics prediction and resource evaluation of ancient reservoirs.The present study improves our understanding on the geochemical characteristics associated with oil cracking processes,and the findings provide solid supports for the evaluation of the thermal stability and the prediction of preservation deadline of oil in Tazhong area in the Tarim Basin.
引文
[1]Hunt J.Petroleum Geochemistry and Geology[M].San Francisco:Freeman,1979.
[2]Hill R J,Tang Y C,Kaplan I R.Insights into oil cracking based on laboratory experiments[J].Organic Geochemistry,2003,34(12):1651-1672.
[3]Tissot B P,Welte D H.Petroleum Formation and Occurrence[G].New York:Springer,1984.
[4]Lewan M D.Experiments on the role of water in petroleum formation[J].Geochimica et Cosmochimica Acta,1997,61(17):3691-3723.
[5]Seewald J S.Organic-inorganic interactions in petroleum-producing sedimentarybasins[J].Nature,2003,426(6964):327-333.
[6]Pan C,Jiang L,Liu J,et al.The effects of calcite and montmorillonite on oil cracking in confined pyrolysis experiments[J].Organic Geochemistry,2010,41(7):611-626.
[7]Price L C.Thermal stability of hydrocarbons in nature-limits,evidence,characteristics,and possible controls[J].Geochimica et Cosmochimica Acta,1993,57(14):3261-3280.
[8]Dahl J E,Moldowan J M,Peters K E,et al.Diamondoid hydrocarbons as indicators of natural oil cracking[J].Nature,1999,399:54-57.
[9]Dahl J E,Liu S G,Carlson R M K.Isolation and structure of higher diamondoids,nanometer-sized diamond molecules[J].Science,2003,299(5603):96-99.
[10]Chen J H,Fu J M,Sheng G Y,et al.Diamondoid hydrocarbon ratios:Novel maturity indices for highly mature crude oils[J].Organic Geochemistry,1996,25(3/4):179-190.
[11]Liu Jinzhong,Tang Yongchun.A case study of prediction methane generation quantity by kinetics simulation of hydrocarbon generating from kerogen[J].Chinese Science Bulletin,1998,43(11):1187-1191.刘金钟,唐永春.用干酪根生烃动力学方法预测甲烷生成量之一例[J].科学通报,1998(10):1187-1191.
[12]Fang C,Xiong Y,Liang Q,et al.Variation in abundance and distribution of diamondoids during oil cracking[J].Organic Geochemistry,2012,47:1-8.
[13]Xiong Yongqiang,Geng Ansong,Sheng Guoying,et al.Characteristics of carbon isotopic composition of N-alkanes during hydrocarbon generation and expulsion and its significance[J].Acta Sedimentologica Sinica,2001,19(3):469-473.熊永强,耿安松,盛国英,等.生排烃过程中正构烷烃单体碳同位素组成的变化特征及其研究意义[J].沉积学报,2001,19(3):469-473.
[14]Lorant F,Prinzhofer A,Behar F,et al.Carbon isotopic and molecular constraints on the formation and the expulsion of thermogenic hydrocarbon gases[J].Chemical Geology,1998,147(3/4):249-264.
[15]Behar F,Kressmann S,Rudkiewicz J L,et al.Experimental simulation in a confined system and kinetic modeling of kerogen and oil cracking[J].Organic Geochemistry,1992,19(1-3):173-189.
[16]Jia Chenzao.Tectonic Characteristics and Petroleum of the Tarim Basin,China[M].Beijing:Petroleum Industry Press,1997.贾承造.中国塔里木盆地构造特征与油气[M].北京:石油工业出版社,1997.
[17]Zhang Shuichang,Liang Digang,Zhang Baomin,et al.Marine Oil and Gas Formation in Tarim Basin[M].Beijing:Petroleum Industry Press,2004.张水昌,梁狄刚,张宝民,等.塔里木盆地海相油气生成[M].北京:石油工业出版社,2004.
[18]Zhang Bin,Huang Ling,Wu Ying,et al.Quantitative evaluation of crude oil composition changes caused by strong gas washing:A case study of natural gas pool in Kuqa Depression[J].Earth Science Frontiers,2010,17(4):270-279.张斌,黄凌,吴英,等.强烈气洗作用导致原油成分变化的定量计算——以库车凹陷天然气藏为例[J].地学前缘,2010,17(4):270-279.
[19]Zhang Shuichang,Zhu Guangyou,He Kun.The effects of thermochemical sulfate reduction on occurrence of oil-cracking gas and reformation of deep carbonate reservoir and the interaction mechanisms[J].Acta Petrologica Sinica,2011,27(3):809-826.张水昌,朱光有,何坤.硫酸盐热化学还原作用对原油裂解撑起和碳酸盐岩储层改造的影响及作用机制[J].岩石学报,2011,27(3):809-826.
[20]Fort R C,Schleyer P V.Adamantane-consequences of diamondoid structure[J].Chemical Reviews,1964,64(3):277-300.
[21]Giruts M V,Gordadze GN.Generation of adamantanes and diamantanes by thermal cracking of polar components of crude oils of different genotypes[J].Petroleum Chemistry,2007,47(1):12-22.
[22]Fang C,Xiong Y,Li Y,et al.The origin and evolution of adamantanes and diamantanes in petroleum[J].Geochimica et Cosmochimica Acta,2013,120:109-120.
[23]Wei Z,Moldowan J M,Peters K E,et al.The abundance and distribution of diamondoids in biodegraded oils from the San Joaquin Valley:Implications for biodegradation of diamondoids in petroleum reservoirs[J].Organic Geochemistry,2007,38(11):1910-1926.
[2]Hill R J,Tang Y C,Kaplan I R.Insights into oil cracking based on laboratory experiments[J].Organic Geochemistry,2003,34(12):1651-1672.
[3]Tissot B P,Welte D H.Petroleum Formation and Occurrence[G].New York:Springer,1984.
[4]Lewan M D.Experiments on the role of water in petroleum formation[J].Geochimica et Cosmochimica Acta,1997,61(17):3691-3723.
[5]Seewald J S.Organic-inorganic interactions in petroleum-producing sedimentarybasins[J].Nature,2003,426(6964):327-333.
[6]Pan C,Jiang L,Liu J,et al.The effects of calcite and montmorillonite on oil cracking in confined pyrolysis experiments[J].Organic Geochemistry,2010,41(7):611-626.
[7]Price L C.Thermal stability of hydrocarbons in nature-limits,evidence,characteristics,and possible controls[J].Geochimica et Cosmochimica Acta,1993,57(14):3261-3280.
[8]Dahl J E,Moldowan J M,Peters K E,et al.Diamondoid hydrocarbons as indicators of natural oil cracking[J].Nature,1999,399:54-57.
[9]Dahl J E,Liu S G,Carlson R M K.Isolation and structure of higher diamondoids,nanometer-sized diamond molecules[J].Science,2003,299(5603):96-99.
[10]Chen J H,Fu J M,Sheng G Y,et al.Diamondoid hydrocarbon ratios:Novel maturity indices for highly mature crude oils[J].Organic Geochemistry,1996,25(3/4):179-190.
[11]Liu Jinzhong,Tang Yongchun.A case study of prediction methane generation quantity by kinetics simulation of hydrocarbon generating from kerogen[J].Chinese Science Bulletin,1998,43(11):1187-1191.刘金钟,唐永春.用干酪根生烃动力学方法预测甲烷生成量之一例[J].科学通报,1998(10):1187-1191.
[12]Fang C,Xiong Y,Liang Q,et al.Variation in abundance and distribution of diamondoids during oil cracking[J].Organic Geochemistry,2012,47:1-8.
[13]Xiong Yongqiang,Geng Ansong,Sheng Guoying,et al.Characteristics of carbon isotopic composition of N-alkanes during hydrocarbon generation and expulsion and its significance[J].Acta Sedimentologica Sinica,2001,19(3):469-473.熊永强,耿安松,盛国英,等.生排烃过程中正构烷烃单体碳同位素组成的变化特征及其研究意义[J].沉积学报,2001,19(3):469-473.
[14]Lorant F,Prinzhofer A,Behar F,et al.Carbon isotopic and molecular constraints on the formation and the expulsion of thermogenic hydrocarbon gases[J].Chemical Geology,1998,147(3/4):249-264.
[15]Behar F,Kressmann S,Rudkiewicz J L,et al.Experimental simulation in a confined system and kinetic modeling of kerogen and oil cracking[J].Organic Geochemistry,1992,19(1-3):173-189.
[16]Jia Chenzao.Tectonic Characteristics and Petroleum of the Tarim Basin,China[M].Beijing:Petroleum Industry Press,1997.贾承造.中国塔里木盆地构造特征与油气[M].北京:石油工业出版社,1997.
[17]Zhang Shuichang,Liang Digang,Zhang Baomin,et al.Marine Oil and Gas Formation in Tarim Basin[M].Beijing:Petroleum Industry Press,2004.张水昌,梁狄刚,张宝民,等.塔里木盆地海相油气生成[M].北京:石油工业出版社,2004.
[18]Zhang Bin,Huang Ling,Wu Ying,et al.Quantitative evaluation of crude oil composition changes caused by strong gas washing:A case study of natural gas pool in Kuqa Depression[J].Earth Science Frontiers,2010,17(4):270-279.张斌,黄凌,吴英,等.强烈气洗作用导致原油成分变化的定量计算——以库车凹陷天然气藏为例[J].地学前缘,2010,17(4):270-279.
[19]Zhang Shuichang,Zhu Guangyou,He Kun.The effects of thermochemical sulfate reduction on occurrence of oil-cracking gas and reformation of deep carbonate reservoir and the interaction mechanisms[J].Acta Petrologica Sinica,2011,27(3):809-826.张水昌,朱光有,何坤.硫酸盐热化学还原作用对原油裂解撑起和碳酸盐岩储层改造的影响及作用机制[J].岩石学报,2011,27(3):809-826.
[20]Fort R C,Schleyer P V.Adamantane-consequences of diamondoid structure[J].Chemical Reviews,1964,64(3):277-300.
[21]Giruts M V,Gordadze GN.Generation of adamantanes and diamantanes by thermal cracking of polar components of crude oils of different genotypes[J].Petroleum Chemistry,2007,47(1):12-22.
[22]Fang C,Xiong Y,Li Y,et al.The origin and evolution of adamantanes and diamantanes in petroleum[J].Geochimica et Cosmochimica Acta,2013,120:109-120.
[23]Wei Z,Moldowan J M,Peters K E,et al.The abundance and distribution of diamondoids in biodegraded oils from the San Joaquin Valley:Implications for biodegradation of diamondoids in petroleum reservoirs[J].Organic Geochemistry,2007,38(11):1910-1926.