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71.
针对辽河油田矿场在开发过程中容易出现地层能量下降和汽窜问题,为了达到改善蒸汽驱的开发效果的目的,选择蒸汽驱发泡剂做为研究对象,以静态性能做为评价指标,开展了发泡剂性能评价效果实验。发泡剂注入地层之后会产生大量泡沫,泡沫对于提高采收率起着重大作用。泡沫一方面起到了增大地层压力,可以驱油。另一方面起到了封窜作用。结果表明:发泡剂质量分数在0.4%时发泡性能最佳。此时发泡剂生成的泡沫量达到最理想效果。优选0.5%为该辽河油田的最优发泡剂质量分数。 相似文献
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The annular pulsed disc-and-doughnut column (APDDC) is an important type of solvent-extraction equipment used in the PUREX process. Though it has been used in several commercial reprocessing plants in the world, there are few research results reported in the literature. In the present work, experiments were carried out in a stainless steel annular pulsed disc-and-doughnut column with aqueous phase and organic phase as the continuous fluid separately. The air-purge method was used to measure parameters including the two-phase densities, column weight, and two-phase interface location, which were fed back to a computer for column control. The holdup and Sauter drop diameter, the latter of which was calculated based on the gravitational settling model, are correlated as functions of the operating conditions (such as pulsation intensity, total flux, and flow ratio). Flooding holdup and throughput were determined experimentally and found in good agreement with those predicted by the model of the Sauter drop diameter. Based on the experimental data, operating regimes are divided referring to existing models. In addition, the effects of internal wettability on the hydraulic characteristics are also discussed. 相似文献
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建立质子交换膜燃料电池一维两相传递模型,通过达西定律和菲克定律的联立求解得到扩散层中的液体饱和度和氧气浓度分布。考察扩散层特性参数孔隙率、厚度、接触角、渗透率对阴极水淹的影响,结果表明扩散层表面憎水将有助于液态水移出,但当达到憎水条件后,增大接触角对液态水传输和氧气传质的影响逐渐变小。憎水条件下孔隙率和厚度对液态水传输的影响不是很明显,但孔隙率增大和扩散层厚度减小均有利于氧气传质,实际应用中孔隙率增大的同时,厚度也要适当增大,极限电流密度相差不大。模型计算结果与文献中不同PTFE含量条件下实验的Tafel斜率和极限电流密度比较,吻合较好。 相似文献
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The hydrodynamics of fluid bed cokers were studied by analyzing pressure fluctuations and particle motion in a half‐column cold model, geometrically and dynamically similar (with key dimensionless groups matched) to the stripper section of two commercial fluid cokers. Superficial gas velocity and solids circulation strongly affected the hydrodynamics. The pressure drop over the top section of the stripper decreased at high solids circulation fluxes and high gas velocities due to flooding. Flooding occurred prematurely when fouling was simulated. Steam redistribution did not improve stripper performance for the conditions investigated. However, steep sheds on the top row, aeration behind the solids exit and standpipe aeration all improved solids circulation, leading to reduced fouling in two commercial fluid cokers. 相似文献
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