The formation of CaO-TiO2-MgO-Al2O3 dual phase inclusion in 321 stainless steel was investigated in the laboratory. The result indicated that the condition for the formation of CaO-TiO2-MgO-Al2O3 in 321 steel is [Ca]...The formation of CaO-TiO2-MgO-Al2O3 dual phase inclusion in 321 stainless steel was investigated in the laboratory. The result indicated that the condition for the formation of CaO-TiO2-MgO-Al2O3 in 321 steel is [Ca]〉0.001wt%, [Ti]〉0.1wt%, and [A1]〉0.01wt%. The mechanism is the following： Al2O3 inclusion turns into CaO-Al2O3 after Ca-Si wire is fed into the molten steel; [Mg] is then obtained by reducing MgO in slag or crucible wall by [Al] and [Ti]; finally CaO-Al2O3 inclusion is changed into CaO-TiO2-MgO-Al2O3 by the reaction with [Mg], [Ti], and [O] in the molten steel simultaneously.展开更多
Based on the analysis of the geological characteristics and controlling factors, we analyzed the formation mechanism of different types of gas reservoirs. The main characteristics of gas provinces with low porosity an...Based on the analysis of the geological characteristics and controlling factors, we analyzed the formation mechanism of different types of gas reservoirs. The main characteristics of gas provinces with low porosity and permeability are mainly as follows: large area, low abundance, small gas pools and large gas provinces; widely distributed excellent hydrocarbon source rocks with closely contacted source-reservoir-cap association; development mainly in large continental depressions or in paralic shallow-river delta systems; many kinds of traps coexisting in large areas, dominantly para-layered lithologic, digenetic and capillary pressure traps; double fluid flow mechanisms of Darcy flow and non-Darcy flow; complicated gas and water relations; and having the resource distribution of highly productive "sweet spots", banding concentration, and macroscopically large areas integrated. The main controlling factors of large sandstone gas provinces with low porosity and permeability are stable dynamic backgrounds and gentle structural frameworks which control the extensive distribution of alternate (interbedded) sandstones and mudstones; weak hydropower of large gentle lake basins controlling the formation of discontinuous, low porosity and permeability reservoirs in shallow-water deltas; regionally differential diagenesis and no homogeneous digenetic facies controlling the development of favorable reservoirs and digenetic traps; and weak and dispersive reservoir-forming dynamic forces leading to the widely distributed small traps with low abundance. Low porosity and permeability gas provinces with different trap types have different formation mechanisms which include fluid diversion pressure difference interactive mechanism of lithologic-trap gas accumulations, separated differential collection mechanism of digenetic-trap gas accumulations, and the Non-Darcy flow mechanism of capillary-pressure gas accumulations.展开更多
基金financially supported by the National Natural Science Foundation of China (No.50374011)
文摘The formation of CaO-TiO2-MgO-Al2O3 dual phase inclusion in 321 stainless steel was investigated in the laboratory. The result indicated that the condition for the formation of CaO-TiO2-MgO-Al2O3 in 321 steel is [Ca]〉0.001wt%, [Ti]〉0.1wt%, and [A1]〉0.01wt%. The mechanism is the following： Al2O3 inclusion turns into CaO-Al2O3 after Ca-Si wire is fed into the molten steel; [Mg] is then obtained by reducing MgO in slag or crucible wall by [Al] and [Ti]; finally CaO-Al2O3 inclusion is changed into CaO-TiO2-MgO-Al2O3 by the reaction with [Mg], [Ti], and [O] in the molten steel simultaneously.
基金Supported by PetroChina Science and Technology Project (Grant No. 07-01C-01-07) Youth Innovation Fund Project (Grant Nos. 10100042KT96, 07-06D-01-04-01-03)
文摘Based on the analysis of the geological characteristics and controlling factors, we analyzed the formation mechanism of different types of gas reservoirs. The main characteristics of gas provinces with low porosity and permeability are mainly as follows: large area, low abundance, small gas pools and large gas provinces; widely distributed excellent hydrocarbon source rocks with closely contacted source-reservoir-cap association; development mainly in large continental depressions or in paralic shallow-river delta systems; many kinds of traps coexisting in large areas, dominantly para-layered lithologic, digenetic and capillary pressure traps; double fluid flow mechanisms of Darcy flow and non-Darcy flow; complicated gas and water relations; and having the resource distribution of highly productive "sweet spots", banding concentration, and macroscopically large areas integrated. The main controlling factors of large sandstone gas provinces with low porosity and permeability are stable dynamic backgrounds and gentle structural frameworks which control the extensive distribution of alternate (interbedded) sandstones and mudstones; weak hydropower of large gentle lake basins controlling the formation of discontinuous, low porosity and permeability reservoirs in shallow-water deltas; regionally differential diagenesis and no homogeneous digenetic facies controlling the development of favorable reservoirs and digenetic traps; and weak and dispersive reservoir-forming dynamic forces leading to the widely distributed small traps with low abundance. Low porosity and permeability gas provinces with different trap types have different formation mechanisms which include fluid diversion pressure difference interactive mechanism of lithologic-trap gas accumulations, separated differential collection mechanism of digenetic-trap gas accumulations, and the Non-Darcy flow mechanism of capillary-pressure gas accumulations.
