An effective parameter in the miscible-CO_2 enhanced oil recovery procedure is the minimum miscibility pressure(MMP)defined as the lowest pressure that the oil in place and the injected gas into reservoir achieve misc...An effective parameter in the miscible-CO_2 enhanced oil recovery procedure is the minimum miscibility pressure(MMP)defined as the lowest pressure that the oil in place and the injected gas into reservoir achieve miscibility at a given temperature. Flue gases released from power plants can provide an available source of CO_2,which would otherwise be emitted to the atmosphere, for injection into a reservoir. However, the costs related to gas extraction from flue gases is potentially high. Hence, greater understanding the role of impurities in miscibility characteristics between CO_2 and reservoir fluids helps to establish which impurities are tolerable and which are not. In this study, we simulate the effects of the impurities nitrogen(N_2), methane(C_1), ethane(C_2) and propane(C_3) on CO_2 MMP. The simulation results reveal that,as an impurity, nitrogen increases CO_2–oil MMP more so than methane. On the other hand, increasing the propane(C_3)content can lead to a significant decrease in CO_2 MMP, whereas varying the concentrations of ethane(C_2) does not have a significant effect on the minimum miscibility pressure of reservoir crude oil and CO_2 gas. The novel relationships established are particularly valuable in circumstances where MMP experimental data are not available.展开更多
This study investigated the effects of gaseous emissions from crude storage tank and gas flaring on air and rainwater quality in Bonny Industrial Island. Ambient air quality parameters, rainwater and weather parameter...This study investigated the effects of gaseous emissions from crude storage tank and gas flaring on air and rainwater quality in Bonny Industrial Island. Ambient air quality parameters, rainwater and weather parameters were collected at 60 m, 80 m, 100 m, 200 m and control plot for 4 weeks at the Bonny. Rainwater parameters were investigated using standard laboratory tests. Data analyses were done using Analysis of variance, pairwise t-test and Pearson’s correlation statistical tools. Results show that emission rates, volatile organic compound (VOC) noise and flare temperature decreased with increasing distance from flare points and crude oil storage tanks. Findings further revealed the emission rates varied significantly with distance away from the gas flaring point (F = 6.196;p = 0.004). The mean concentration of pollutants between gas flare site and crude oil storage tank showed that CO (0.02 ± 0.001 - 0.002 ±0.001), SPM (0.011 ± 0.001 - 0.01 ± 0.001), VOC (0.005 ± 0.001 - 0.01 ± 0.001) and NO<sub>2</sub> (0.04 ± 0.001 - 0.005 ± 0.000) had significant variations (p > 0.05) with CO, O<sub>3</sub> and NO<sub>2</sub> having higher concentrations at the gas flare site while SPM, and VOC were higher around the crude oil storage tank site. Wind turbulence was higher around the gas flaring point (4.93 TKE) than the crude oil storage tank (4.55 TKE). Similarly, there was significant variation in the sun radiation, precipitation, and wind speed caused by gas flaring (1582.25 w/m<sup>2</sup>, 436.25 mm, 0.53 m/s) and crude oil storage tank (1536.25 w/m<sup>2</sup>, 3.91.41 mm, 0.51 m/s). There were also significant variations in flared temperature (F = 22.144;p = 0.001);NO<sub>2</sub> (F = 8.250;p = 0.001), CO (F = 6.000;p = 0.004) and VOC (F = 5.574;p = 0.006) with distance from the gas flaring point. The variation in the rainwater parameters with distance from the gas flaring indicated significant variations in pH (F = 5.594;p = 0.006). The study showed that the concentration of VOC and particulates were high in the supposedly control area which is perceived to be safe for human habitation. Significant variations exist in emission rate (p = 0.015), flare temperature (p = 0.001), NO<sub>2</sub> (p = 0.003), VOC (p = 0.001), noise (p = 0.041), hydrogen carbonate (p = 0.037) and chromium (p = 0.032) between the gas flaring and crude oil storage tank. Regular monitoring is advocated to mitigate the harmful effects of the pollutants.展开更多
Measurements of the absolute and relative concentrations of nitrogen-containing compounds in crude oils from different reservoir strata (Ordovician, Silurian and Carboniferous) in the Tazhong region of the Tarim Basin...Measurements of the absolute and relative concentrations of nitrogen-containing compounds in crude oils from different reservoir strata (Ordovician, Silurian and Carboniferous) in the Tazhong region of the Tarim Basin, Xinjiang, China, showed that even though there are quite a number of factors affecting the distributional and compositional characteristics of neutral nitrogen-containing compounds in crude oils, the distributional and compositional characteristics of crude oils whose source conditions are approximate to one another are influenced mainly by the migration and fractionation effects in the process of formation of oil reservoirs. In addition, crude oils in the Tazhong region show obvious migration-fractionation effects in the vertical direction. Carboniferous crude oils are characterized by high migration parameters and low compound concentrations, just in contrast to Ordovician crude oils. This indicates that crude oils from shallow-level oil reservoirs were derived from those of deep-level oil reservoirs via faults, unconformable contact or carrier beds. Crude oils from the Tazhong region show some migration-fractionation effects in the lateral direction, but mixing of crude oils derived from different hydrocarbon source rocks in the process of formation of oil reservoirs made it more complicated the migration and accumulation of crude oils, as well as the formation of oil reservoirs.展开更多
In 2016,China's net imports of crude oil increased to 378.3 million tons and its net exports of product oil soared to 20.45 million tons.Refinery crude runs continue to grow at a low rate,and the domestic product ...In 2016,China's net imports of crude oil increased to 378.3 million tons and its net exports of product oil soared to 20.45 million tons.Refinery crude runs continue to grow at a low rate,and the domestic product oil market still has a supply surplus.Diesel consumption fell for the first time in 21 years.The liquefied petroleum gas(LPG) market continues to grow rapidly,spurred on by feedstock demand for chemicals and gasoline blending components,and imports of LPG have reached a record high of 16.12 million tons.The refinery throughput of Petro China and SINOPEC had declined for 2 consecutive years,but crude oil imports climbed to a new high of 381 million tons as independent refineries boosted their utilization of capacity and the domestic oilfields produced a decreased amount of output.Imported oil now accounts for more than 2/3 of the Chinese market compared to being only about 1/3 15 years ago.Moreover,the proportion of imported crude in refinery runs has risen to 70%.In 2017,China's economy will continue to face substantial pressure,and domestic demand for product oil will continue to grow slowly.展开更多
The composition characteristics of light hydrocarbons from crude oil,chloroform bitumen A,saturated hydrocarbon fraction,aromatic hydrocarbon fraction,and asphaltene fraction during cracking have been studied systemat...The composition characteristics of light hydrocarbons from crude oil,chloroform bitumen A,saturated hydrocarbon fraction,aromatic hydrocarbon fraction,and asphaltene fraction during cracking have been studied systematically. The results revealed that the content of n-alkanes,branched alkanes and cycloalkanes in light hydrocarbons from the samples gradually decreased as the simulation temperature increased,and finally almost depleted completely,while the abundance of methane,benzene and its homologues increased obviously and became the main products. The ratios of benzene/n-hexane and toluene/n-heptane can be used as measures for oil cracking levels. Variation characteristics of maturity parameters of light hydrocarbons,for example,iC4/nC4,iC5/nC5,isoheptane value,2,2-DMC4/nC6,and 2-MC6+3-MC6/nC7 for different samples with increasing pyrolysis temperature,are consistent with those in petroleum reservoirs,indicating that these parameters may be efficient maturity index.展开更多
Continuous exploration has triggered a heated debate on hydrocarbon resource potential in the southern slope zone of the Kuqa foreland basin,and sources of the Mesozoic-Cenozoic oil and gas have become a key problem t...Continuous exploration has triggered a heated debate on hydrocarbon resource potential in the southern slope zone of the Kuqa foreland basin,and sources of the Mesozoic-Cenozoic oil and gas have become a key problem to be solved in this region.Composition and organic geochemical parameters of crude oil and natural gas from the southern slope zone of the Kuqa foreland basin were illustrated in order to reveal their origin by using a combination of gas chromatograph(GC),gas chromatogram-mass spectrum(GC-MS)and carbon isotope analyses.The characteristics of crude oil,such as low density,viscosity,solidification point and sulfur content,and high wax content,indicate that source of the crude oil is continental.The biomarker compositions of crude oil are characterized by low to medium molecular weight compounds(n-C_(12) to n-C_(20)),high Pr/Ph ratios(>1.0),low phytane/n-C18 ratios(0.06-0.54),and predominant regular sterane C_(29).All biomarker parameters clearly indicate that the crude oil was derived mainly from algae and aquatic plankton and deposited under weak reduction-oxidation environment,and has the characteristics of mixed kerogens.The Cretaceous crude oil was mainly derived from the Triassic lacustrine source rocks,which also contributed to the Paleogene crude oil together with Jurassic coal source rocks.Natural gas is characterized by moderate methane content,high heavy hydrocarbon and nitrogen content,and no hydrogen sulfide.The methane and ethane in Paleogene natural gas are relatively rich in ^(13)C withδ^(13)C_(1) andδ^(13)C_(2) values ranging from-37.3‰to-31.2‰(mean=-34.25‰)and from-25‰to-21.3‰(mean=-23.09‰),respectively,indicating the coal-derived gas from the Middle and Lower Jurassic strata.Hydrocarbon products in the southern slope zone of the Kuqa foreland basin are primarily generated from source rocks in the mature stage.The low-amplitude structural and lithologic traps with the updip pinch-out sand bodies or plugging secondary fault at relatively high tectonic positions are the most favorable areas for discovery and breakthrough in the study area.Results of this study will provide useful information for controlling factors of reservoirs and oil and gas exploration deployment in the southern slope zone of the Kuqa foreland basin.展开更多
This paper presents an evaluation of the energy intensity and related greenhouse gas/CO2 emissions of integrated oil sands crude upgrading processes. Two major oil sands crude upgrading schemes currently used in Canad...This paper presents an evaluation of the energy intensity and related greenhouse gas/CO2 emissions of integrated oil sands crude upgrading processes. Two major oil sands crude upgrading schemes currently used in Canadian oil sands operations were investigated： cokingbased and hydroconversion-based. The analysis, which was based on a robust process model of the entire process, was constructed in Aspen HYSYS and calibrated with representative data. Simulations were conducted for the two upgrading schemes in order to generate a detailed inventory of the required energy and utility inputs： process fuel, steam, hydrogen and power. It was concluded that while hydroconversion-based scheme yields considerably higher amount of synthetic crude oil （SCO） than the cokerbased scheme （94 wt-% vs. 76 wt-%）, it consumes more energy and is therefore more CO2-intensive （413.2kg CO2/m3sco vs. 216.4kg CO2/m^3sco）. This substantial difference results from the large amount of hydrogen consumed in the ebullated-bed hydroconverter in the hydroconversion-based scheme, as hydrogen production through conventional methane steam reforming is highly energy-intensive and therefore the major source of CO2 emission. Further simulations indicated that optimization of hydroconverter operating variables had only a minor effect on the overall CO2 emission due to the complex trade-off effect between energy inputs.展开更多
文摘An effective parameter in the miscible-CO_2 enhanced oil recovery procedure is the minimum miscibility pressure(MMP)defined as the lowest pressure that the oil in place and the injected gas into reservoir achieve miscibility at a given temperature. Flue gases released from power plants can provide an available source of CO_2,which would otherwise be emitted to the atmosphere, for injection into a reservoir. However, the costs related to gas extraction from flue gases is potentially high. Hence, greater understanding the role of impurities in miscibility characteristics between CO_2 and reservoir fluids helps to establish which impurities are tolerable and which are not. In this study, we simulate the effects of the impurities nitrogen(N_2), methane(C_1), ethane(C_2) and propane(C_3) on CO_2 MMP. The simulation results reveal that,as an impurity, nitrogen increases CO_2–oil MMP more so than methane. On the other hand, increasing the propane(C_3)content can lead to a significant decrease in CO_2 MMP, whereas varying the concentrations of ethane(C_2) does not have a significant effect on the minimum miscibility pressure of reservoir crude oil and CO_2 gas. The novel relationships established are particularly valuable in circumstances where MMP experimental data are not available.
文摘This study investigated the effects of gaseous emissions from crude storage tank and gas flaring on air and rainwater quality in Bonny Industrial Island. Ambient air quality parameters, rainwater and weather parameters were collected at 60 m, 80 m, 100 m, 200 m and control plot for 4 weeks at the Bonny. Rainwater parameters were investigated using standard laboratory tests. Data analyses were done using Analysis of variance, pairwise t-test and Pearson’s correlation statistical tools. Results show that emission rates, volatile organic compound (VOC) noise and flare temperature decreased with increasing distance from flare points and crude oil storage tanks. Findings further revealed the emission rates varied significantly with distance away from the gas flaring point (F = 6.196;p = 0.004). The mean concentration of pollutants between gas flare site and crude oil storage tank showed that CO (0.02 ± 0.001 - 0.002 ±0.001), SPM (0.011 ± 0.001 - 0.01 ± 0.001), VOC (0.005 ± 0.001 - 0.01 ± 0.001) and NO<sub>2</sub> (0.04 ± 0.001 - 0.005 ± 0.000) had significant variations (p > 0.05) with CO, O<sub>3</sub> and NO<sub>2</sub> having higher concentrations at the gas flare site while SPM, and VOC were higher around the crude oil storage tank site. Wind turbulence was higher around the gas flaring point (4.93 TKE) than the crude oil storage tank (4.55 TKE). Similarly, there was significant variation in the sun radiation, precipitation, and wind speed caused by gas flaring (1582.25 w/m<sup>2</sup>, 436.25 mm, 0.53 m/s) and crude oil storage tank (1536.25 w/m<sup>2</sup>, 3.91.41 mm, 0.51 m/s). There were also significant variations in flared temperature (F = 22.144;p = 0.001);NO<sub>2</sub> (F = 8.250;p = 0.001), CO (F = 6.000;p = 0.004) and VOC (F = 5.574;p = 0.006) with distance from the gas flaring point. The variation in the rainwater parameters with distance from the gas flaring indicated significant variations in pH (F = 5.594;p = 0.006). The study showed that the concentration of VOC and particulates were high in the supposedly control area which is perceived to be safe for human habitation. Significant variations exist in emission rate (p = 0.015), flare temperature (p = 0.001), NO<sub>2</sub> (p = 0.003), VOC (p = 0.001), noise (p = 0.041), hydrogen carbonate (p = 0.037) and chromium (p = 0.032) between the gas flaring and crude oil storage tank. Regular monitoring is advocated to mitigate the harmful effects of the pollutants.
文摘Measurements of the absolute and relative concentrations of nitrogen-containing compounds in crude oils from different reservoir strata (Ordovician, Silurian and Carboniferous) in the Tazhong region of the Tarim Basin, Xinjiang, China, showed that even though there are quite a number of factors affecting the distributional and compositional characteristics of neutral nitrogen-containing compounds in crude oils, the distributional and compositional characteristics of crude oils whose source conditions are approximate to one another are influenced mainly by the migration and fractionation effects in the process of formation of oil reservoirs. In addition, crude oils in the Tazhong region show obvious migration-fractionation effects in the vertical direction. Carboniferous crude oils are characterized by high migration parameters and low compound concentrations, just in contrast to Ordovician crude oils. This indicates that crude oils from shallow-level oil reservoirs were derived from those of deep-level oil reservoirs via faults, unconformable contact or carrier beds. Crude oils from the Tazhong region show some migration-fractionation effects in the lateral direction, but mixing of crude oils derived from different hydrocarbon source rocks in the process of formation of oil reservoirs made it more complicated the migration and accumulation of crude oils, as well as the formation of oil reservoirs.
文摘In 2016,China's net imports of crude oil increased to 378.3 million tons and its net exports of product oil soared to 20.45 million tons.Refinery crude runs continue to grow at a low rate,and the domestic product oil market still has a supply surplus.Diesel consumption fell for the first time in 21 years.The liquefied petroleum gas(LPG) market continues to grow rapidly,spurred on by feedstock demand for chemicals and gasoline blending components,and imports of LPG have reached a record high of 16.12 million tons.The refinery throughput of Petro China and SINOPEC had declined for 2 consecutive years,but crude oil imports climbed to a new high of 381 million tons as independent refineries boosted their utilization of capacity and the domestic oilfields produced a decreased amount of output.Imported oil now accounts for more than 2/3 of the Chinese market compared to being only about 1/3 15 years ago.Moreover,the proportion of imported crude in refinery runs has risen to 70%.In 2017,China's economy will continue to face substantial pressure,and domestic demand for product oil will continue to grow slowly.
基金Supported by the National Natural Science Foundation of China (Grant No. 40573030)the National Key Science and Technology Program of China During the 10th Five-Year Plan Period (Grant No. 2004BA616A02-01-01-03)
文摘The composition characteristics of light hydrocarbons from crude oil,chloroform bitumen A,saturated hydrocarbon fraction,aromatic hydrocarbon fraction,and asphaltene fraction during cracking have been studied systematically. The results revealed that the content of n-alkanes,branched alkanes and cycloalkanes in light hydrocarbons from the samples gradually decreased as the simulation temperature increased,and finally almost depleted completely,while the abundance of methane,benzene and its homologues increased obviously and became the main products. The ratios of benzene/n-hexane and toluene/n-heptane can be used as measures for oil cracking levels. Variation characteristics of maturity parameters of light hydrocarbons,for example,iC4/nC4,iC5/nC5,isoheptane value,2,2-DMC4/nC6,and 2-MC6+3-MC6/nC7 for different samples with increasing pyrolysis temperature,are consistent with those in petroleum reservoirs,indicating that these parameters may be efficient maturity index.
基金sponsored by the National Science and Technology Major Project in the 13th Five-Year Plan(Nos.2016ZX05003-001,2017ZX05001-002)the Science and Technology Project of the China Petroleum and Natural Gas Co.Ltd.(No.KT2018-02-06)。
文摘Continuous exploration has triggered a heated debate on hydrocarbon resource potential in the southern slope zone of the Kuqa foreland basin,and sources of the Mesozoic-Cenozoic oil and gas have become a key problem to be solved in this region.Composition and organic geochemical parameters of crude oil and natural gas from the southern slope zone of the Kuqa foreland basin were illustrated in order to reveal their origin by using a combination of gas chromatograph(GC),gas chromatogram-mass spectrum(GC-MS)and carbon isotope analyses.The characteristics of crude oil,such as low density,viscosity,solidification point and sulfur content,and high wax content,indicate that source of the crude oil is continental.The biomarker compositions of crude oil are characterized by low to medium molecular weight compounds(n-C_(12) to n-C_(20)),high Pr/Ph ratios(>1.0),low phytane/n-C18 ratios(0.06-0.54),and predominant regular sterane C_(29).All biomarker parameters clearly indicate that the crude oil was derived mainly from algae and aquatic plankton and deposited under weak reduction-oxidation environment,and has the characteristics of mixed kerogens.The Cretaceous crude oil was mainly derived from the Triassic lacustrine source rocks,which also contributed to the Paleogene crude oil together with Jurassic coal source rocks.Natural gas is characterized by moderate methane content,high heavy hydrocarbon and nitrogen content,and no hydrogen sulfide.The methane and ethane in Paleogene natural gas are relatively rich in ^(13)C withδ^(13)C_(1) andδ^(13)C_(2) values ranging from-37.3‰to-31.2‰(mean=-34.25‰)and from-25‰to-21.3‰(mean=-23.09‰),respectively,indicating the coal-derived gas from the Middle and Lower Jurassic strata.Hydrocarbon products in the southern slope zone of the Kuqa foreland basin are primarily generated from source rocks in the mature stage.The low-amplitude structural and lithologic traps with the updip pinch-out sand bodies or plugging secondary fault at relatively high tectonic positions are the most favorable areas for discovery and breakthrough in the study area.Results of this study will provide useful information for controlling factors of reservoirs and oil and gas exploration deployment in the southern slope zone of the Kuqa foreland basin.
文摘This paper presents an evaluation of the energy intensity and related greenhouse gas/CO2 emissions of integrated oil sands crude upgrading processes. Two major oil sands crude upgrading schemes currently used in Canadian oil sands operations were investigated： cokingbased and hydroconversion-based. The analysis, which was based on a robust process model of the entire process, was constructed in Aspen HYSYS and calibrated with representative data. Simulations were conducted for the two upgrading schemes in order to generate a detailed inventory of the required energy and utility inputs： process fuel, steam, hydrogen and power. It was concluded that while hydroconversion-based scheme yields considerably higher amount of synthetic crude oil （SCO） than the cokerbased scheme （94 wt-% vs. 76 wt-%）, it consumes more energy and is therefore more CO2-intensive （413.2kg CO2/m3sco vs. 216.4kg CO2/m^3sco）. This substantial difference results from the large amount of hydrogen consumed in the ebullated-bed hydroconverter in the hydroconversion-based scheme, as hydrogen production through conventional methane steam reforming is highly energy-intensive and therefore the major source of CO2 emission. Further simulations indicated that optimization of hydroconverter operating variables had only a minor effect on the overall CO2 emission due to the complex trade-off effect between energy inputs.
