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排序方式: 共有93条查询结果,搜索用时 15 毫秒
1.
Watson S.J. Barry D.A. Schotting R.J. Hassanizadeh S.M. 《Transport in Porous Media》2002,47(2):149-167
Recently, it has been suggested that Darcy's Law might not be applicable for modelling miscible, density-dependent flow in porous media. To investigate this, three sets of careful laboratory column experiments were performed on coarse and medium sands, consisting of upward displacement of water by sodium chloride solutions with concentrations ranging from 5 to 200g/l. Data on salt concentrations and water pressures were collected in horizontal transects along the flow direction. Salt concentration data were also collected in the influent and exit lines. The experimental data were analysed using a simplified approach based on Darcy's Law alone, applied with the assumption of a sharp interface. Darcy's Law was used to estimate porous medium permeability by fitting predictions to experimental data. Consistent estimates of permeability were obtained for each set of experiments. The results indicate that Darcy's Law adequately describes high concentration displacements through saturated coarse- and medium-grained porous media. 相似文献
2.
Sebastian Geiger Thomas Driesner Christoph A. Heinrich Stephan K. Matthäi 《Transport in Porous Media》2006,63(3):399-434
We present a new finite element – finite volume (FEFV) method combined with a realistic equation of state for NaCl–H2O to model fluid convection driven by temperature and salinity gradients. This method can deal with the nonlinear variations
in fluid properties, separation of a saline fluid into a high-density, high-salinity brine phase and low-density, low-salinity
vapor phase well above the critical point of pure H2O, and geometrically complex geological structures. Similar to the well-known implicit pressure explicit saturation formulation,
this approach decouples the governing equations. We formulate a fluid pressure equation that is solved using an implicit finite
element method. We derive the fluid velocities from the updated pressure field and employ them in a higher-order, mass conserving
finite volume formulation to solve hyperbolic parts of the conservation laws. The parabolic parts are solved by finite element
methods. This FEFV method provides for geometric flexibility and numerical efficiency. The equation of state for NaCl–H2O is valid from 0 to 750°C, 0 to 4000 bar, and 0–100 wt.% NaCl. This allows the simulation of thermohaline convection in high-temperature
and high-pressure environments, such as continental or oceanic hydrothermal systems where phase separation is common. 相似文献
3.
盐湖资源开发利用进展 总被引:17,自引:0,他引:17
本世纪头十年里,国际上再度掀起盐湖资源开发热潮。这很大程度上是由于锂的开发热带动的,同时也是和钾肥的广泛施用、价格一路走高有关。南美安第斯高原地区盐湖蕴藏世界70%以上的锂资源,且卤水锂、钾、硼浓度高。该地区极度干旱,少雨多风,非常适合采用卤水盐田蒸发的节能浓缩工艺技术。老的盐湖开发企业则在钾肥需求的带动下,稳步发展。在我国,新疆罗布泊和青海柴达木盆地盐湖则钾锂镁硼产品多元化,经营多元化取得长足进步。本文对近十年来,国内外盐湖开发的新动向做了概括介绍,特别着重于南美"锂三角"地区这一新的生长点。 相似文献
4.
Solid-liquid phase equilibria of the two ternary systems (NaCl+SrCl2+H2O) and (KCl+SrCl2+H2O) at T=288.15 K and p=0.1 MPa were studied using the isothermal dissolution equilibrium method. Solubilities of the equilibrium liquid phase were determined, and the solids were also investigated by the Schreinemaker method of wet residues. In the ternary system (NaCl+SrCl2+H2O) at 288.15 K, there is one invariant point corresponding to (NaCl+SrCl2·6H2O) and two crystallization regions corresponding to NaCl and SrCl2·6H2O. The crystallized area of SrCl2·6H2O decreased with the increasing temperature, while that of NaCl increased slightly. In the ternary system (KCl+SrCl2+H2O) at 288.15 K, there is one invariant point(KCl+SrCl2·6H2O) and two crystallization regions corresponding to KCl and SrCl2·6H2O. Both systems belong to a simple eutectic type, and neither double salts nor solid solutions were formed. On the basis of Pitzer-Harvie-Weare model, the solubilities of the two systems at 288.15 K were demonstrated. A comparison showed that the calculated solubilities agreed well with the experimental data. 相似文献
5.
The effect of low-salinity (1000 to 5000?ppm) and intermediate-salinity (5000 to 40000?ppm) water (MgSO4, MgCl2, Na2SO4, CaCl2, NaCl and KCl) on asphaltene precipitation was investigated in this work. The results revealed that all brines intensify the amount of asphaltene precipitation. All cases exhibited initial downward trend followed by the upward trend for the amount of asphaltene precipitation with increasing the brine concentration. A similar trend was also observed for Interfacial Tension (IFT) between crude oil and brine in this study. IFT was tested for MgSO4, MgCl2, Na2SO4, CaCl2, NaCl and KCl brines with concentrations of 1000 to 40000?ppm. Finally, experimental results showed that an increase in volume of all brines in the mixture (brine +oil) led to increase and decrease of the asphaltene precipitation in low and intermediate salinity regions, respectively. 相似文献
6.
Metal (M) oxide (M: Ir, Os, Pd, Pt, Rh, Ru) together with MaO2 and MnO2 alone, were coated on SnO2 films and the anode behavior was examined in 1.0 N H2SO4, 1.0 N NaOH and 1.0, N NaCl aqueous solutions at 25°. The results are compared with those of DSA and of metallic Pt. 相似文献
7.
我国锂资源及其开发技术进展 总被引:6,自引:0,他引:6
介绍了我国盐湖锂资源的现状及其开发技术的进展情况,讨论了各种提锂工艺的优缺点,并对现阶段我国盐湖锂资源的开发提出了建议。 相似文献
8.
The isoplethic sections in the diagram of the quaternary system Na+ , Mg2+ //Cl– , SO2– 4 –H2 O were established at 25 and 30oC by analytical and conductometric measurements. Three compounds can be observed in the isoplethic sections: NaCl, Na2 SO4 and MgNa2 (SO4 )2 4 H2 O. Seven fields are determined, relating to the precipitation of one, two or three salts. The solubility range of MgNa2 (SO4 )2 4 H2 O is wide, while the liquidus curve of Na2 SO4 is very short. The compositions, expressed in Jänecke coordinates, at the eutonic and peritonic points, respectively, were: 42.70% Cl– and 745% H2 O; 79.47% Cl– and 787% H2 O; 71.6% Cl– and 744% H2 O at 25°C; and 48.80% Cl– and 715% H2 O; 80.20% Cl– and 778% H2 O; 70.14% Cl– and 707% H2 O at 30°C. 相似文献
9.
盐卤硼酸盐化学研究进展 总被引:13,自引:0,他引:13
综述了近20年来从事青藏高原新类型硼酸盐盐湖“盐卤硼酸盐化学”的研究进展。 相似文献
10.