Three major elements, carbon, hydrogen, and nitrogen, in twenty-four bituminous coal samples, were measured by laser-induced breakdown spectroscopy. Argon and helium were applied as ambient gas to enhance the signals ...Three major elements, carbon, hydrogen, and nitrogen, in twenty-four bituminous coal samples, were measured by laser-induced breakdown spectroscopy. Argon and helium were applied as ambient gas to enhance the signals and eliminate the interference of nitrogen from surrounding air. The relative standard deviation of the related emission lines and the performance in the partial least squares (PLS) modeling were compared for different ambient environments. The results showed that argon not only improved the intensity, but also reduced signal fluctuation. The PLS model also had the optimal performance in multi-element analysis using argon as ambient gas. The root mean square error of prediction of carbon concentration decreased from 4.25% in air to 3.49% in argon, while the average relative error reduced from 4.96% to 2.98%. Hydrogen line demonstrated similar improvement. Yet, the nitrogen lines were too weak to be detected even in an argon environment which suggested the nitrogen signal measured in air come from the breakdown of nitrogen molecules in the atmosphere.展开更多
Silurian sandstone in Tarim Basin has good reservoir properties and active oil and gas shows, especially thick widely-distributed bituminous sandstone. Currently, the Silurian was found containing both bitumen and con...Silurian sandstone in Tarim Basin has good reservoir properties and active oil and gas shows, especially thick widely-distributed bituminous sandstone. Currently, the Silurian was found containing both bitumen and conventional reservoirs, with petroleum originating from terrestrial and marine source rocks. The diversity of their distribution was the result of "three sources, three stages" accumulation and adjustment processes. "Three sources" refers to two sets of marine rocks in Cambrian and Middle-Upper Ordovician, and a set of terrestrial rock formed in Triassic in the Kuqa depression. "Three stages" represents three stages of accumulation, adjustment and reformation occurring in Late Caledonian, Late Hercynian and Late Himalayan, respectively. The study suggests that the Silurian bitumen is remnants of oil generated from Cambrian and Ordovician source rocks and accumulated in the sandstone reservoir during Late Caledonian-Early Hercynian and Late Hercynian stages, and then damaged by the subsequent two stages of tectonic uplift movements in Early Hercynian and Pre-Triassic. The authors presumed that the primary paleo-reservoirs formed during these two stages might he preserved in the Silurian in the southern deep part of the Tabei area. Except for the Yingmaili area where the Triassic terrestrial oil was from the Kuqa Depression during Late Himalayan Stage, all movable oil reservoirs originated from marine sources. They were secondary accumulations from underlying Ordovician after structure reverse during the Yanshan- Himalayan stage. Oil/gas shows mixed-source characteristics, and was mainly from Middle-Upper Ordovician. The complexity and diversity of the Silurian marine primary properties were just defined by these three stages of oil-gas charging and tectonic movements in the Tabei area.展开更多
An experimental study on co-pyrolysis of bituminous coal and biomass was performed in a pressured fluidized bed reactor.The blend ratio of biomass in the mixture was varied between 0 and 100 wt%,and the temperature wa...An experimental study on co-pyrolysis of bituminous coal and biomass was performed in a pressured fluidized bed reactor.The blend ratio of biomass in the mixture was varied between 0 and 100 wt%,and the temperature was over a range of 550–650℃ under 1.0 MPa pressure with different atmospheres.On the basis of the individual pyrolysis behavior of bituminous coal and biomass,the influences of the biomass blending ratio,temperature,pressure and atmosphere on the product distribution were investigated.The results indicated that there existed a synergetic effect in the co-pyrolysis of bituminous coal and biomass in this pressured fluidized bed reactor,especially when the condition of bituminous coal and biomass blend ratio of 70:30(w/w),600℃,and 0.3 MPa was applied.The addition of biomass influenced the tar and char yields and gas and tar composition during co-pyrolysis.The tar yields were higher than the calculated values from individual pyrolysis of each fuel,and consequently the char yields were lower.The experimental results showed that the composition of the gaseous products was not in accordance with those of their individual fuel.The improvement of composition in tar also indicated synergistic effect in the co-pyrolysis.展开更多
The suppression of nitrogen oxides(NO_x) is the key to reducing pollutant emission of a domestic coal-fired stove due to the limitation of technology condition and economic cost. The decoupling combustion(DC) technolo...The suppression of nitrogen oxides(NO_x) is the key to reducing pollutant emission of a domestic coal-fired stove due to the limitation of technology condition and economic cost. The decoupling combustion(DC) technology invented by Institute of Process Engineering(IPE), Chinese Academy of Sciences(CAS) is characterized by that a traditional stove is separated into a pyrolysis and a combustion chamber as well as a bottom passage between them. In this study, the combustion of briquette from bituminous coal in different operation modes in a typical decoupling stove is tested and simulated to validate the advantage of DC technology over so-called reverse combustion. The smokeless and high-efficiency combustion of bituminous briquette with low emissions of NO_x and CO can be implemented by utilizing low NO_x combustion under low temperature and reduction atmosphere in the pyrolysis chamber as well as after-combustion of char and pyrolysis gas under high temperature and oxidation atmosphere in the combustion chamber. The effects of the main reducing components in pyrolysis gas as well as char on NO_x reduction were numerically investigated in this study, which shows that the reducing ability increases gradually from CH_4, CO to char, but the combined reducing ability of them cannot be determined by a simple addition.展开更多
The adsorption behavior of CO_2, CH_4 and their mixtures in bituminous coal was investigated in this study. First, a bituminous coal model was built through molecular dynamic(MD) simulations, and it was confirmed to b...The adsorption behavior of CO_2, CH_4 and their mixtures in bituminous coal was investigated in this study. First, a bituminous coal model was built through molecular dynamic(MD) simulations, and it was confirmed to be reasonable by comparing the simulated results with the experimental data. Grand Canonical Monte Carlo(GCMC)simulations were then carried out to investigate the single and binary component adsorption of CO_2 and CH_4with the built bituminous coal model. For the single component adsorption, the isosteric heat of CO_2 adsorption is greater than that of CH_4 adsorption. CO_2 also exhibits stronger electrostatic interactions with the heteroatom groups in the bituminous coal model compared with CH_4, which can account for the larger adsorption capacity of CO_2 in the bituminous coal model. In the case of binary adsorption of CO_2 and CH_4mixtures, CO_2 exhibits the preferential adsorption compared with CH_4 under the studied conditions. The adsorption selectivity of CO_2 exhibited obvious change with increasing pressure. At lower pressure, the adsorption selectivity of CO_2 shows a rapid decrease with increasing the temperature, whereas it becomes insensitive to temperature at higher pressure. Additionally, the adsorption selectivity of CO_2 decreases gradually with the increase of the bulk CO_2 mole fraction and the depth of CO_2 injection site.展开更多
In Greece more than 60,000 tn End of Life Tires are stockpiled every year often uncontrollable, causing severe environmental and other socio-economic negative impacts. Studies up to date are focused mainly on mechanic...In Greece more than 60,000 tn End of Life Tires are stockpiled every year often uncontrollable, causing severe environmental and other socio-economic negative impacts. Studies up to date are focused mainly on mechanical and physical characteristics of rubberized mixtures (based on cement, asphalt or soil) in which tire rubber is used either as alternative to natural aggregates or as additive. However, effect of tire rubber on noise reduction in rubberized bituminous layers, which is the main topic of present paper, has not been widely studied. In particular, this research paper is dealing with a sustainable use of tire rubber in asphalt pavement, leading to its generated noise reduction. An experimental pilot application has been conducted in the frame of a European Research Project, which has been implemented in a heavy traffic road section, cited outside Lamia city of Greece, (Vasilikon Street). The upper surface layer of the pavement has been made of rubberized bituminous mixture, produced by the wet process. Rheological characteristics of rubberized bitumen as well as basic properties of the implemented, rubberized bituminous mixture are presented. Moreover, measurements of noise level, deriving from vehicles’ motion, under operational conditions took place at the road section right after its implementation as well as after 8 months of its operation, while all data are presented in details. Results of the measurements on conventional and modified pavement sections are compared, certifying that rubberized asphalt layers can be not only environmentally friendly—since a category of solid wastes (worn automobile tires) is utilized—but also, addition of tire rubber particles in bituminous binder provides up to 3dB noise reducing bituminous mixtures and pavements, noise reduction that remains even after 8 months of road section’s operation.展开更多
In most countries, there is a low temperature limit to lay down hot asphalt mixes because if it is too cold, it becomes impossible to get proper compaction. For cold recycled bituminous mixture(CRM), there is little i...In most countries, there is a low temperature limit to lay down hot asphalt mixes because if it is too cold, it becomes impossible to get proper compaction. For cold recycled bituminous mixture(CRM), there is little information on the effect of the low temperature on their behavior. The goal of this study is to evaluate, in laboratory, the impact of the compaction and curing temperature on the behavior of CRM. To do so, CRM containing 50%reclaimed asphalt pavement(RAP) and 50% natural aggregates treated with foamed asphalt or bituminous emulsion were mixed and cured at different temperature between 0 and23℃ for up to 10 days before being tested in indirect tension. The results show that for all mixes, a cure at lower temperature means lower tensile strength, but the decrease is more noticeable for emulsion treated materials than for foamed treated mixes. The trend is not as obvious for Marshall stability results. A second cure at ambient temperature was also done, and the analysis of the results showed that the decrease in mechanical performance remains important even after a second cure at higher temperature for all mixes treated with bituminous emulsion, but there is some mechanical gain for mixes treated with foamed asphalt.展开更多
基金Acknowledgements The authors are grateful for the financial support from the National Natural Science Foundation of China (Grant No. 51061130536).
文摘Three major elements, carbon, hydrogen, and nitrogen, in twenty-four bituminous coal samples, were measured by laser-induced breakdown spectroscopy. Argon and helium were applied as ambient gas to enhance the signals and eliminate the interference of nitrogen from surrounding air. The relative standard deviation of the related emission lines and the performance in the partial least squares (PLS) modeling were compared for different ambient environments. The results showed that argon not only improved the intensity, but also reduced signal fluctuation. The PLS model also had the optimal performance in multi-element analysis using argon as ambient gas. The root mean square error of prediction of carbon concentration decreased from 4.25% in air to 3.49% in argon, while the average relative error reduced from 4.96% to 2.98%. Hydrogen line demonstrated similar improvement. Yet, the nitrogen lines were too weak to be detected even in an argon environment which suggested the nitrogen signal measured in air come from the breakdown of nitrogen molecules in the atmosphere.
基金funded by the PetroChina scientific and research funding
文摘Silurian sandstone in Tarim Basin has good reservoir properties and active oil and gas shows, especially thick widely-distributed bituminous sandstone. Currently, the Silurian was found containing both bitumen and conventional reservoirs, with petroleum originating from terrestrial and marine source rocks. The diversity of their distribution was the result of "three sources, three stages" accumulation and adjustment processes. "Three sources" refers to two sets of marine rocks in Cambrian and Middle-Upper Ordovician, and a set of terrestrial rock formed in Triassic in the Kuqa depression. "Three stages" represents three stages of accumulation, adjustment and reformation occurring in Late Caledonian, Late Hercynian and Late Himalayan, respectively. The study suggests that the Silurian bitumen is remnants of oil generated from Cambrian and Ordovician source rocks and accumulated in the sandstone reservoir during Late Caledonian-Early Hercynian and Late Hercynian stages, and then damaged by the subsequent two stages of tectonic uplift movements in Early Hercynian and Pre-Triassic. The authors presumed that the primary paleo-reservoirs formed during these two stages might he preserved in the Silurian in the southern deep part of the Tabei area. Except for the Yingmaili area where the Triassic terrestrial oil was from the Kuqa Depression during Late Himalayan Stage, all movable oil reservoirs originated from marine sources. They were secondary accumulations from underlying Ordovician after structure reverse during the Yanshan- Himalayan stage. Oil/gas shows mixed-source characteristics, and was mainly from Middle-Upper Ordovician. The complexity and diversity of the Silurian marine primary properties were just defined by these three stages of oil-gas charging and tectonic movements in the Tabei area.
基金Supported by Hydrocarbon High-efficiency Utilization Technology Research Center of Yanchang Petroleum(Group)Co.Ltd.,China(ycsy2013ky-A-30)
文摘An experimental study on co-pyrolysis of bituminous coal and biomass was performed in a pressured fluidized bed reactor.The blend ratio of biomass in the mixture was varied between 0 and 100 wt%,and the temperature was over a range of 550–650℃ under 1.0 MPa pressure with different atmospheres.On the basis of the individual pyrolysis behavior of bituminous coal and biomass,the influences of the biomass blending ratio,temperature,pressure and atmosphere on the product distribution were investigated.The results indicated that there existed a synergetic effect in the co-pyrolysis of bituminous coal and biomass in this pressured fluidized bed reactor,especially when the condition of bituminous coal and biomass blend ratio of 70:30(w/w),600℃,and 0.3 MPa was applied.The addition of biomass influenced the tar and char yields and gas and tar composition during co-pyrolysis.The tar yields were higher than the calculated values from individual pyrolysis of each fuel,and consequently the char yields were lower.The experimental results showed that the composition of the gaseous products was not in accordance with those of their individual fuel.The improvement of composition in tar also indicated synergistic effect in the co-pyrolysis.
基金financial supports from the "Transformational Technologies for Clean Energy and Demonstration",Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA21040400)the National Natural Science Foundation of China(Nos21376244 and 91334107)
文摘The suppression of nitrogen oxides(NO_x) is the key to reducing pollutant emission of a domestic coal-fired stove due to the limitation of technology condition and economic cost. The decoupling combustion(DC) technology invented by Institute of Process Engineering(IPE), Chinese Academy of Sciences(CAS) is characterized by that a traditional stove is separated into a pyrolysis and a combustion chamber as well as a bottom passage between them. In this study, the combustion of briquette from bituminous coal in different operation modes in a typical decoupling stove is tested and simulated to validate the advantage of DC technology over so-called reverse combustion. The smokeless and high-efficiency combustion of bituminous briquette with low emissions of NO_x and CO can be implemented by utilizing low NO_x combustion under low temperature and reduction atmosphere in the pyrolysis chamber as well as after-combustion of char and pyrolysis gas under high temperature and oxidation atmosphere in the combustion chamber. The effects of the main reducing components in pyrolysis gas as well as char on NO_x reduction were numerically investigated in this study, which shows that the reducing ability increases gradually from CH_4, CO to char, but the combined reducing ability of them cannot be determined by a simple addition.
基金Supported by the CNPC Huabei Oilfield Science and Technology Development Project(HBYT-CYY-2014-JS-378,HBYT-CYY-2015-JS-47)
文摘The adsorption behavior of CO_2, CH_4 and their mixtures in bituminous coal was investigated in this study. First, a bituminous coal model was built through molecular dynamic(MD) simulations, and it was confirmed to be reasonable by comparing the simulated results with the experimental data. Grand Canonical Monte Carlo(GCMC)simulations were then carried out to investigate the single and binary component adsorption of CO_2 and CH_4with the built bituminous coal model. For the single component adsorption, the isosteric heat of CO_2 adsorption is greater than that of CH_4 adsorption. CO_2 also exhibits stronger electrostatic interactions with the heteroatom groups in the bituminous coal model compared with CH_4, which can account for the larger adsorption capacity of CO_2 in the bituminous coal model. In the case of binary adsorption of CO_2 and CH_4mixtures, CO_2 exhibits the preferential adsorption compared with CH_4 under the studied conditions. The adsorption selectivity of CO_2 exhibited obvious change with increasing pressure. At lower pressure, the adsorption selectivity of CO_2 shows a rapid decrease with increasing the temperature, whereas it becomes insensitive to temperature at higher pressure. Additionally, the adsorption selectivity of CO_2 decreases gradually with the increase of the bulk CO_2 mole fraction and the depth of CO_2 injection site.
文摘In Greece more than 60,000 tn End of Life Tires are stockpiled every year often uncontrollable, causing severe environmental and other socio-economic negative impacts. Studies up to date are focused mainly on mechanical and physical characteristics of rubberized mixtures (based on cement, asphalt or soil) in which tire rubber is used either as alternative to natural aggregates or as additive. However, effect of tire rubber on noise reduction in rubberized bituminous layers, which is the main topic of present paper, has not been widely studied. In particular, this research paper is dealing with a sustainable use of tire rubber in asphalt pavement, leading to its generated noise reduction. An experimental pilot application has been conducted in the frame of a European Research Project, which has been implemented in a heavy traffic road section, cited outside Lamia city of Greece, (Vasilikon Street). The upper surface layer of the pavement has been made of rubberized bituminous mixture, produced by the wet process. Rheological characteristics of rubberized bitumen as well as basic properties of the implemented, rubberized bituminous mixture are presented. Moreover, measurements of noise level, deriving from vehicles’ motion, under operational conditions took place at the road section right after its implementation as well as after 8 months of its operation, while all data are presented in details. Results of the measurements on conventional and modified pavement sections are compared, certifying that rubberized asphalt layers can be not only environmentally friendly—since a category of solid wastes (worn automobile tires) is utilized—but also, addition of tire rubber particles in bituminous binder provides up to 3dB noise reducing bituminous mixtures and pavements, noise reduction that remains even after 8 months of road section’s operation.
文摘In most countries, there is a low temperature limit to lay down hot asphalt mixes because if it is too cold, it becomes impossible to get proper compaction. For cold recycled bituminous mixture(CRM), there is little information on the effect of the low temperature on their behavior. The goal of this study is to evaluate, in laboratory, the impact of the compaction and curing temperature on the behavior of CRM. To do so, CRM containing 50%reclaimed asphalt pavement(RAP) and 50% natural aggregates treated with foamed asphalt or bituminous emulsion were mixed and cured at different temperature between 0 and23℃ for up to 10 days before being tested in indirect tension. The results show that for all mixes, a cure at lower temperature means lower tensile strength, but the decrease is more noticeable for emulsion treated materials than for foamed treated mixes. The trend is not as obvious for Marshall stability results. A second cure at ambient temperature was also done, and the analysis of the results showed that the decrease in mechanical performance remains important even after a second cure at higher temperature for all mixes treated with bituminous emulsion, but there is some mechanical gain for mixes treated with foamed asphalt.