Thermal simulation experiment of gas generation from the peat and the coals were performed using the high temperature and pressure apparatus, at temperature ranging from 336.8-600℃, a pressure of 50MPa and two heatin...Thermal simulation experiment of gas generation from the peat and the coals were performed using the high temperature and pressure apparatus, at temperature ranging from 336.8-600℃, a pressure of 50MPa and two heating rates of 20℃/h and 2℃/h, and the evolution and formation of coalbed gas components were studied. Results show that for the coals, the gaseous products are mainly composed of hydrocarbon gases. However, for the peat the content of hydrocarbon gases in gaseous products is lower than that of non-hydrocarbon components. In the generated hydrocarbon gases methane is predominant and heavy hydrocarbon gases (C2-5) are present in small amount. Meanwhile, carbon dioxide (CO2) predominates the generated non-hydrocarbon gases, and hydrogen (H2) and sul-furated hydrogen (H2S) are existent in trace amount. It is also observed that temperature is the main factor controlling the evolution of coalbed gas generation. With increasing vitrinite reflectance, methane rapidly increases, CO2 sightly increases, and C2-5 hydrocarbons first increase and then decrease. The peat and Shanxi formation coal have a higher generative potential of coalbed gases than coals and Taiyuan formation coal, respectively, reflecting the effect of the property of organic matter on the characteristics of coalbed gas component generation. In this study, it is found that low heating rate is favorable for the generation of methane, H2 and CO2, and the decomposition of C2-5 hydrocarbons. This shows that heating time plays an important controlling role in the generation and evolution of coalbed gases. The results obtained from the simulation experiment in the study of coalbed gases in natural system are also discussed.展开更多
The Pearl River Mouth Basin(PRMB)is one of the most petroliferous basins on the northern margin of the South China Sea.Knowledge of the thermal history of the PRMB is significant for understanding its tectonic evoluti...The Pearl River Mouth Basin(PRMB)is one of the most petroliferous basins on the northern margin of the South China Sea.Knowledge of the thermal history of the PRMB is significant for understanding its tectonic evolution and for unraveling its poorly studied source-rock maturation history.Our investigations in this study are based on apatite fission-track(AFT)thermochronology analysis of 12 cutting samples from 4 boreholes.Both AFT ages and length data suggested that the PRMB has experienced quite complicated thermal evolution.Thermal history modeling results unraveled four successive events of heating separated by three stages of cooling since the early Middle Eocene.The cooling events occurred approximately in the Late Eocene,early Oligocene,and the Late Miocene,possibly attributed to the Zhuqiong II Event,Nanhai Event,and Dongsha Event,respectively.The erosion amount during the first cooling stage is roughly estimated to be about 455-712 m,with an erosion rate of 0.08-0.12 mm/a.The second erosion-driven cooling is stronger than the first one,with an erosion amount of about 747-814 m and an erosion rate between about 0.13-0.21 mm/a.The erosion amount calculated related to the third cooling event varies from 800 m to 3419 m,which is speculative due to the possible influence of the magmatic activity.展开更多
No-bake resin-bonded sand is commonly used in casting production.However,its air pollution is relatively serious,especially in the molding and pouring process.For this reason,it is necessary to study the gas evolution...No-bake resin-bonded sand is commonly used in casting production.However,its air pollution is relatively serious,especially in the molding and pouring process.For this reason,it is necessary to study the gas evolution characteristics of no-bake resin-bonded sand from room temperature to high temperatures,and not only the amount of gaseous products,but also the composition of the gaseous products.No-bake furan resin-bonded sand(#1),phenolic urethane no-bake resin-bonded sand(#2),and alkaline phenolic no-bake resin-bonded sand(#3)are the three most common no-bake resin-bonded sands in casting.The gas evolution volume and rate of these three no-bake resin-bonded sands were studied.Thermogravimetry-mass spectrometer(TG-MS),headspace-gas chromatography/mass spectrometer(HS-GC/MS),and pyrolysis-gas chromatography/mass spectrometer(PY-GC/MS)were used to measure the composition of the gaseous products emitted from binders at room temperature and high temperatures.The differences between formaldehyde,heterocyclic aromatic compounds(HAC),monocyclic aromatic hydrocarbons(MAH),and polycyclic aromatic hydrocarbons(PAHs)gaseous products from the three types of no-bake resin-bonded sands during the molding and casting process were compared.From the perspective of environmental protection,alkaline phenolic no-bake resin-bonded sand and no-bake furan resin-bonded sand are better than phenolic urethane no-bake resin-bonded sand.展开更多
文摘Thermal simulation experiment of gas generation from the peat and the coals were performed using the high temperature and pressure apparatus, at temperature ranging from 336.8-600℃, a pressure of 50MPa and two heating rates of 20℃/h and 2℃/h, and the evolution and formation of coalbed gas components were studied. Results show that for the coals, the gaseous products are mainly composed of hydrocarbon gases. However, for the peat the content of hydrocarbon gases in gaseous products is lower than that of non-hydrocarbon components. In the generated hydrocarbon gases methane is predominant and heavy hydrocarbon gases (C2-5) are present in small amount. Meanwhile, carbon dioxide (CO2) predominates the generated non-hydrocarbon gases, and hydrogen (H2) and sul-furated hydrogen (H2S) are existent in trace amount. It is also observed that temperature is the main factor controlling the evolution of coalbed gas generation. With increasing vitrinite reflectance, methane rapidly increases, CO2 sightly increases, and C2-5 hydrocarbons first increase and then decrease. The peat and Shanxi formation coal have a higher generative potential of coalbed gases than coals and Taiyuan formation coal, respectively, reflecting the effect of the property of organic matter on the characteristics of coalbed gas component generation. In this study, it is found that low heating rate is favorable for the generation of methane, H2 and CO2, and the decomposition of C2-5 hydrocarbons. This shows that heating time plays an important controlling role in the generation and evolution of coalbed gases. The results obtained from the simulation experiment in the study of coalbed gases in natural system are also discussed.
基金This study is financially supported by the National Natural Science Foundation of China(42072181).
文摘The Pearl River Mouth Basin(PRMB)is one of the most petroliferous basins on the northern margin of the South China Sea.Knowledge of the thermal history of the PRMB is significant for understanding its tectonic evolution and for unraveling its poorly studied source-rock maturation history.Our investigations in this study are based on apatite fission-track(AFT)thermochronology analysis of 12 cutting samples from 4 boreholes.Both AFT ages and length data suggested that the PRMB has experienced quite complicated thermal evolution.Thermal history modeling results unraveled four successive events of heating separated by three stages of cooling since the early Middle Eocene.The cooling events occurred approximately in the Late Eocene,early Oligocene,and the Late Miocene,possibly attributed to the Zhuqiong II Event,Nanhai Event,and Dongsha Event,respectively.The erosion amount during the first cooling stage is roughly estimated to be about 455-712 m,with an erosion rate of 0.08-0.12 mm/a.The second erosion-driven cooling is stronger than the first one,with an erosion amount of about 747-814 m and an erosion rate between about 0.13-0.21 mm/a.The erosion amount calculated related to the third cooling event varies from 800 m to 3419 m,which is speculative due to the possible influence of the magmatic activity.
基金financially supported by the National Natural Science Foundation of China (Grant Nos. U1808216, 51905188)the National Key R&D Program of China (Grant No. 2020YFB1710100)
文摘No-bake resin-bonded sand is commonly used in casting production.However,its air pollution is relatively serious,especially in the molding and pouring process.For this reason,it is necessary to study the gas evolution characteristics of no-bake resin-bonded sand from room temperature to high temperatures,and not only the amount of gaseous products,but also the composition of the gaseous products.No-bake furan resin-bonded sand(#1),phenolic urethane no-bake resin-bonded sand(#2),and alkaline phenolic no-bake resin-bonded sand(#3)are the three most common no-bake resin-bonded sands in casting.The gas evolution volume and rate of these three no-bake resin-bonded sands were studied.Thermogravimetry-mass spectrometer(TG-MS),headspace-gas chromatography/mass spectrometer(HS-GC/MS),and pyrolysis-gas chromatography/mass spectrometer(PY-GC/MS)were used to measure the composition of the gaseous products emitted from binders at room temperature and high temperatures.The differences between formaldehyde,heterocyclic aromatic compounds(HAC),monocyclic aromatic hydrocarbons(MAH),and polycyclic aromatic hydrocarbons(PAHs)gaseous products from the three types of no-bake resin-bonded sands during the molding and casting process were compared.From the perspective of environmental protection,alkaline phenolic no-bake resin-bonded sand and no-bake furan resin-bonded sand are better than phenolic urethane no-bake resin-bonded sand.
