Thermochemical sulfate reduction （TSR） is the reaction between anhydrite and petroleum fluids at elevated temperatures to produce H2S and CO2. TSR has been studied in many sedimentary basins such as China＇s Sichuan...Thermochemical sulfate reduction （TSR） is the reaction between anhydrite and petroleum fluids at elevated temperatures to produce H2S and CO2. TSR has been studied in many sedimentary basins such as China＇s Sichuan and Tarim basins because it has a profound impact on the commercial viability of petroleum resources, with HzS typically being undesirable.展开更多
The kinetic characteristics of alkenes involved in thermochemical sulfate reduction (TSR) have been never reported in geological literature. In this study, TSR by ethene under hydrothermal conditions was performed in ...The kinetic characteristics of alkenes involved in thermochemical sulfate reduction (TSR) have been never reported in geological literature. In this study, TSR by ethene under hydrothermal conditions was performed in the constrained simulation experiments. Typical TSR products consisted of H<sub>2</sub>S, CO<sub>2</sub>, mercaptans, sulfides, thiophenes derivatives and benzothiophene. The apparent activation energy <i>E</i> and apparent frequency factor <i>A</i> for TSR by ethene were determined as 76.370 kJ/mol and 4.579 s<sup>-1</sup>, respectively. The lower activation energy for ethene involved in TSR relative to ethane suggested that the reactivity of ethene is much higher than that of ethane, in accordance with the thermodynamic analysis. Rate constants were determined experimentally using first-order kinetics extrapolate to MgSO<sub>4</sub> half-lives of 67.329 years - 3.053 years in deep burial diagenetic settings (120°C - 180°C). These values demonstrate that the reaction rate for TSR by ethene is extraordinarily fast in high-temperature gas reservoirs (120°C - 180°C). Consequently, the newly formed ethene from thermal cracking and TSR alteration of natural gas and/or petroleum could not survive after TSR process and were rarely detected in natural TSR reservoirs.展开更多
天然气形成过程中的加氢作用和 TSR 反应是有机-无机相互作用的重要方式。相邻水体和深部来源的氢,是天然气形成的重要氢源,塔里木盆地天然气的甲烷氢同位素组成明显表现出不同沉积水体对甲烷氢同位素的控制作用,大宛105～25井和阿克1...天然气形成过程中的加氢作用和 TSR 反应是有机-无机相互作用的重要方式。相邻水体和深部来源的氢,是天然气形成的重要氢源,塔里木盆地天然气的甲烷氢同位素组成明显表现出不同沉积水体对甲烷氢同位素的控制作用,大宛105～25井和阿克1井具有深部流体加氢的特征;TSR 反应中硫同位素在不同反应阶段和反应过程具有不同的分馏特征,这种特征在四川盆地高舍硫天然气中具有很好的表现,TSR 反应硫同位素分馏一般小于20‰,而单体硫、黄铁矿和硫酸盐矿物等其它反应过程的产物硫同位素分馏不明显。展开更多
Thermochemical sulfate reduction (TSR) in geological deposits can account for the accumulation of H2S in deep sour gas reservoirs. In this paper, thermal simulation experiments on the reaction of CH4-CaSO4 were carri...Thermochemical sulfate reduction (TSR) in geological deposits can account for the accumulation of H2S in deep sour gas reservoirs. In this paper, thermal simulation experiments on the reaction of CH4-CaSO4 were carried out using an autoclave at high temperatures and high pressures. The products were characterized with analytical methods including carbon isotope analysis. It is found that the reaction can proceed to produce H2S, H2O and CaCO3 as the main products. Based on the experimental results, the carbon kinetic isotope fractionation was investigated, and the value of Ki (kinetic isotope effect) was calculated. The results obtained in this paper can provide useful information to explain the occurrence of H2S in deep carbonate gas reservoirs.展开更多
The main reservoirs of Majiang fossil deposits consist of the Silurian Wengxiang group,dominantly sandstones,and the Ordovician Honghuayuan formation,dominantly carbonate rocks,and the Lower Cambrian Niutitang Formati...The main reservoirs of Majiang fossil deposits consist of the Silurian Wengxiang group,dominantly sandstones,and the Ordovician Honghuayuan formation,dominantly carbonate rocks,and the Lower Cambrian Niutitang Formation mudstones serve as the major source rocks.Thermochemical sulfate reduction(TSR)might have taken place in the Paleozoic marine carbonate oil pools,as indicated by high concentrations of dibenzothiophenes in the extracts(MDBT=0.27 4.32 g/g extract,and MDBT/MPH=0.71 1.38).Hydrocarbons in the Pojiaozhai Ordovician carbonate reservoirs have undergone severe TSR and are characterized by higher quantities of diamondoids and MDBT and heavier isotopic values(13C=28.4‰).The very large amounts of dibenzothiophenes might be products of reactions between biphenyls and sulfur species associated with TSR.展开更多
基金supported by the National Natural Science Foundation of China(grant No.41530314)Geological Survey Program(grant No.1212291313016001)
文摘Thermochemical sulfate reduction （TSR） is the reaction between anhydrite and petroleum fluids at elevated temperatures to produce H2S and CO2. TSR has been studied in many sedimentary basins such as China＇s Sichuan and Tarim basins because it has a profound impact on the commercial viability of petroleum resources, with HzS typically being undesirable.
文摘The kinetic characteristics of alkenes involved in thermochemical sulfate reduction (TSR) have been never reported in geological literature. In this study, TSR by ethene under hydrothermal conditions was performed in the constrained simulation experiments. Typical TSR products consisted of H<sub>2</sub>S, CO<sub>2</sub>, mercaptans, sulfides, thiophenes derivatives and benzothiophene. The apparent activation energy <i>E</i> and apparent frequency factor <i>A</i> for TSR by ethene were determined as 76.370 kJ/mol and 4.579 s<sup>-1</sup>, respectively. The lower activation energy for ethene involved in TSR relative to ethane suggested that the reactivity of ethene is much higher than that of ethane, in accordance with the thermodynamic analysis. Rate constants were determined experimentally using first-order kinetics extrapolate to MgSO<sub>4</sub> half-lives of 67.329 years - 3.053 years in deep burial diagenetic settings (120°C - 180°C). These values demonstrate that the reaction rate for TSR by ethene is extraordinarily fast in high-temperature gas reservoirs (120°C - 180°C). Consequently, the newly formed ethene from thermal cracking and TSR alteration of natural gas and/or petroleum could not survive after TSR process and were rarely detected in natural TSR reservoirs.
文摘天然气形成过程中的加氢作用和 TSR 反应是有机-无机相互作用的重要方式。相邻水体和深部来源的氢,是天然气形成的重要氢源,塔里木盆地天然气的甲烷氢同位素组成明显表现出不同沉积水体对甲烷氢同位素的控制作用,大宛105～25井和阿克1井具有深部流体加氢的特征;TSR 反应中硫同位素在不同反应阶段和反应过程具有不同的分馏特征,这种特征在四川盆地高舍硫天然气中具有很好的表现,TSR 反应硫同位素分馏一般小于20‰,而单体硫、黄铁矿和硫酸盐矿物等其它反应过程的产物硫同位素分馏不明显。
文摘Thermochemical sulfate reduction (TSR) in geological deposits can account for the accumulation of H2S in deep sour gas reservoirs. In this paper, thermal simulation experiments on the reaction of CH4-CaSO4 were carried out using an autoclave at high temperatures and high pressures. The products were characterized with analytical methods including carbon isotope analysis. It is found that the reaction can proceed to produce H2S, H2O and CaCO3 as the main products. Based on the experimental results, the carbon kinetic isotope fractionation was investigated, and the value of Ki (kinetic isotope effect) was calculated. The results obtained in this paper can provide useful information to explain the occurrence of H2S in deep carbonate gas reservoirs.
基金supported by the State Key Project of Petroleum(2008ZX05005-001-009HZ)the National Natural Science Foundation of China(41172126)+1 种基金the State Key Laboratory of Petroleum Resources and Prospecting(PRP2010-01)the Science Foundation of China University of Petroleum(LLYJ-2011-05 and KYJJ-2012-01-01)
文摘The main reservoirs of Majiang fossil deposits consist of the Silurian Wengxiang group,dominantly sandstones,and the Ordovician Honghuayuan formation,dominantly carbonate rocks,and the Lower Cambrian Niutitang Formation mudstones serve as the major source rocks.Thermochemical sulfate reduction(TSR)might have taken place in the Paleozoic marine carbonate oil pools,as indicated by high concentrations of dibenzothiophenes in the extracts(MDBT=0.27 4.32 g/g extract,and MDBT/MPH=0.71 1.38).Hydrocarbons in the Pojiaozhai Ordovician carbonate reservoirs have undergone severe TSR and are characterized by higher quantities of diamondoids and MDBT and heavier isotopic values(13C=28.4‰).The very large amounts of dibenzothiophenes might be products of reactions between biphenyls and sulfur species associated with TSR.
