Abstract Unforeseen clogging and low well productivity during exploitation of oil and gas reservoirs result from a mobilisation of densely deposited particles. The proposed model predicts the mobilisation in unsaturated porous media based on the changes in water level, and hydrophilicity and size of mobilisable particles. Domains of particle attachment, sliding, rolling, and lifting were found from a phase diagram based on a mechanical equilibrium. The degree of mobilisation was correlated with experimental data through a maximum retention function. The validity of the proposed model was confirmed by a close match of theoretical predictions with results of 46 laboratory tests on particle detachment. Our analysis shows that it is practically impossible to remove 2 μm charged colloids from a dry porous media. Nearly desalinated water with ionic strength of 0.001 M or less are needed to mobilise particles in saturated media at typical groundwater conditions. A gradual increase in water level is key for mobilisation in unsaturated media. The proposed model can be used to forecast a potential well clogging.

中文翻译：

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多孔介质中胶体的水位和流动性

摘要 油气藏开采过程中不可预见的堵塞和低产井是由于密集沉积颗粒的移动造成的。所提出的模型根据水位的变化以及可移动颗粒的亲水性和大小来预测在不饱和多孔介质中的移动。从基于机械平衡的相图中发现了粒子附着、滑动、滚动和提升的域。动员程度通过最大保留函数与实验数据相关联。理论预测与 46 次实验室粒子脱离测试结果的密切匹配证实了所提出模型的有效性。我们的分析表明，从干燥的多孔介质中去除 2 μm 带电胶体实际上是不可能的。在典型的地下水条件下，需要离子强度为 0.001 M 或更低的近乎淡化的水来移动饱和介质中的颗粒。水位的逐渐增加是在不饱和介质中流动的关键。所提出的模型可用于预测潜在的井堵塞。