Lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and superalloys.To prepare lightweight refractories for the working lining of high...Lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and superalloys.To prepare lightweight refractories for the working lining of high-temperature furnaces,the synthesis of lightweight aggregates is the basis.Recently,the research on the synthesis of lightweight aggregates with high service temperature,low thermal conductivity,high strength,and good slag resistance has received widespread attention.The available literature on the synthesis of lightweight aggregates was summarized,including corundum,mullite,mullite-corundum,spinel,corundum-spinel,cordierite,cordierite-mullite,calcium hexaluminate,corundum-calcium hexaluminate,bauxite,magnesia,magnesia-based,and forsterite-based aggregates.Finally,the future development trend of lightweight aggregates was proposed.展开更多
In situ Raman analysis on the segregated near-equilibrium carbonate-fluid interaction at elevated temperatures(room temperature-260 °C) and pressures(13-812 MPa) in a hydrothermal diamond anvil cell(HDAC) reveals...In situ Raman analysis on the segregated near-equilibrium carbonate-fluid interaction at elevated temperatures(room temperature-260 °C) and pressures(13-812 MPa) in a hydrothermal diamond anvil cell(HDAC) reveals the preservation mechanism of porosity in deep carbonate reservoirs in the northeastern Sichuan Basin. The carbonate-fluid interaction was investigated by separately heating carbonate minerals and rocks with four different acid solutions(saturated CO2 and H2 S solutions, HCl, CH3COOH) in a sealed sample chamber. A minor continuous precipitation with increasing temperatures and pressures was observed during the experiments which caused minor sample volume change. The closed system is a preservation of pores and burial dissolution may not be the dominant diagenesis in the origin of porosity. Thin section photomicrographs observations in Changxing and Feixianguan Formations demonstrate that eogenetic pores such as moldic or intragranular pores with late small euhedral minerals, intergranular, intercrystal and biological cavity pores are the main pore types for the reservoirs. Early fast deep burial makes the porous carbonate sediments get into the closed system as soon as possible and preserves the pores created in the early diagenetic stage to make significant contribution to the deep reservoir quality. The anomalous high porosity at a given depth may come from the inheritance of primary pores and eogenetic porosity is fundamental to carbonate reservoir development. The favorable factors for deep reservoir origin include durable meteoric leaching, early fast deep burial, early dolomitization, etc. This deep pores preservation mechanism may be of great importance to the further exploration in deep carbonate reservoirs in the northeastern Sichuan Basin.展开更多
Closed-cell aluminum foam has incomparable advantages over other traditional materials for thermal insulation and heatpreservation because of small thermal conductivity coefficient. Spherical bubble three-dimensional ...Closed-cell aluminum foam has incomparable advantages over other traditional materials for thermal insulation and heatpreservation because of small thermal conductivity coefficient. Spherical bubble three-dimensional model of aluminum foam is builtto deduce the relationship among pore wall thickness, porosity and average pore size. Non-uniform closed-cell foam aluminummodel with different structural parameters and random pore distribution is established based on the relationship via C programminglanguage. And the temperature distribution is analyzed with ANSYS software. Results indicate that thermal conductivity increaseswith the reducing of porosity. For the aluminum foam with the same porosity, different pore distributions result in different thermalconductivities. The temperature distribution in aluminum foam is non-uniform, which is closely related with the pore size anddistribution. The pores which extend or distribute along the direction perpendicular to heat flow strengthen obstructive capability forheat flow. When pores connect along the direction perpendicular to heat flow, a “wall of high thermal resistance” appears to declinethe thermal conductivity rapidly, which shows that only porosity cannot completely determine effective thermal conductivity ofclosed-cell aluminum foam.展开更多
基金supported by the Starting Grants of Institute of Metal Research,Chinese Academy of Science(E255L401).
文摘Lightweight refractories for the working lining of high-temperature furnaces play an important role in the smelting of advanced steels and superalloys.To prepare lightweight refractories for the working lining of high-temperature furnaces,the synthesis of lightweight aggregates is the basis.Recently,the research on the synthesis of lightweight aggregates with high service temperature,low thermal conductivity,high strength,and good slag resistance has received widespread attention.The available literature on the synthesis of lightweight aggregates was summarized,including corundum,mullite,mullite-corundum,spinel,corundum-spinel,cordierite,cordierite-mullite,calcium hexaluminate,corundum-calcium hexaluminate,bauxite,magnesia,magnesia-based,and forsterite-based aggregates.Finally,the future development trend of lightweight aggregates was proposed.
基金Project(2011ZX05005-003-010HZ)supported by the National Science and Technology Major Project,ChinaProjects(41272137,41002029)supported by the National Natural Science Foundation of China
文摘In situ Raman analysis on the segregated near-equilibrium carbonate-fluid interaction at elevated temperatures(room temperature-260 °C) and pressures(13-812 MPa) in a hydrothermal diamond anvil cell(HDAC) reveals the preservation mechanism of porosity in deep carbonate reservoirs in the northeastern Sichuan Basin. The carbonate-fluid interaction was investigated by separately heating carbonate minerals and rocks with four different acid solutions(saturated CO2 and H2 S solutions, HCl, CH3COOH) in a sealed sample chamber. A minor continuous precipitation with increasing temperatures and pressures was observed during the experiments which caused minor sample volume change. The closed system is a preservation of pores and burial dissolution may not be the dominant diagenesis in the origin of porosity. Thin section photomicrographs observations in Changxing and Feixianguan Formations demonstrate that eogenetic pores such as moldic or intragranular pores with late small euhedral minerals, intergranular, intercrystal and biological cavity pores are the main pore types for the reservoirs. Early fast deep burial makes the porous carbonate sediments get into the closed system as soon as possible and preserves the pores created in the early diagenetic stage to make significant contribution to the deep reservoir quality. The anomalous high porosity at a given depth may come from the inheritance of primary pores and eogenetic porosity is fundamental to carbonate reservoir development. The favorable factors for deep reservoir origin include durable meteoric leaching, early fast deep burial, early dolomitization, etc. This deep pores preservation mechanism may be of great importance to the further exploration in deep carbonate reservoirs in the northeastern Sichuan Basin.
基金Project(51304254)supported by the National Natural Science Foundation of ChinaProject(2015JC3001)supported by the Ministry of Science and Technology of Hunan Province,China
文摘Closed-cell aluminum foam has incomparable advantages over other traditional materials for thermal insulation and heatpreservation because of small thermal conductivity coefficient. Spherical bubble three-dimensional model of aluminum foam is builtto deduce the relationship among pore wall thickness, porosity and average pore size. Non-uniform closed-cell foam aluminummodel with different structural parameters and random pore distribution is established based on the relationship via C programminglanguage. And the temperature distribution is analyzed with ANSYS software. Results indicate that thermal conductivity increaseswith the reducing of porosity. For the aluminum foam with the same porosity, different pore distributions result in different thermalconductivities. The temperature distribution in aluminum foam is non-uniform, which is closely related with the pore size anddistribution. The pores which extend or distribute along the direction perpendicular to heat flow strengthen obstructive capability forheat flow. When pores connect along the direction perpendicular to heat flow, a “wall of high thermal resistance” appears to declinethe thermal conductivity rapidly, which shows that only porosity cannot completely determine effective thermal conductivity ofclosed-cell aluminum foam.
