Determination of contact angles and pore sizes of porous media by column and thin layer wicking

A glass wool media is commonly classified as a medium made up of many capillaries. They might, however, be considered analogous to a network of tubes as a bundle of capillaries. The capillary pressure of such a medium would be dependent on the amount of fluid held within the bundles. But, this very simple picture of porous media does not capture all the characteristics of this imbibition. We have determined capillaries radii by using Washburn and Laplace relations. Laplace radius can also be obtained by 3 approaches: using White’s relation and using Jurin’s law with visualized height and with weight. We have observed a single value of capillary radius cannot be used to determine the infiltration height as a function of time. This mechanism of capillary infiltration can be controlled by pores of more than one size and pores are interconnected.

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Determination of contact angles for three-phase flow in porous media using an energy balance

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2020.07.152 ◽

2021 ◽

Vol 582 ◽

pp. 283-290 ◽

Cited By ~ 2

Author(s):

Martin J. Blunt ◽

Abdulla Alhosani ◽

Qingyang Lin ◽

Alessio Scanziani ◽

Branko Bijeljic

Keyword(s):

Porous Media ◽

Energy Balance ◽

Contact Angles ◽

Flow In Porous Media ◽

Phase Flow ◽

Three Phase ◽

Three Phase Flow

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Determination of Contact Angles on Microporous Particles Using the Thin-Layer Wicking Technique

Langmuir ◽

10.1021/la0510578 ◽

2005 ◽

Vol 21 (18) ◽

pp. 8319-8325 ◽

Cited By ~ 23

Author(s):

Zheng-Gang Cui ◽

Bernard P. Binks ◽

John H. Clint

Keyword(s):

Thin Layer ◽

Contact Angles

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Wettability Characterization from Pore-Scale Images Using Topology and Energy Balance with Implications for Recovery and Storage

10.2118/206202-ms ◽

2021 ◽

Author(s):

Martin Blunt ◽

Luke Kearney ◽

Abdulla Alhosani ◽

Qingyang Lin ◽

Branko Bijeljic

Keyword(s):

Contact Angle ◽

Porous Media ◽

Energy Balance ◽

Accurate Determination ◽

Direct Determination ◽

Contact Angles ◽

Pore Scale ◽

Three Phase ◽

And Storage

Abstract We present two methods to measure contact angles inside porous media using high-resolution images. The direct determination of contact angle at the three-phase contact line is often ambiguous due to uncertainties with image segmentation. Instead, we propose two alternative approaches that provide an averaged assessment of wettability. The first uses fundamental principles in topology to relate the contact angle to the integral of the Gaussian curvature over the fluid-fluid meniscus. The advantage of this approach is that it replaces the uncertain determination of an angle at a point with a more accurate determination of an integral over a surface. However, in mixed-wet porous media, many interfaces are pinned with a hinging contact angle. For predictive pore-scale models, we need to determine the contact angle at which displacement occurs when the interfaces move. To address this problem we apply an energy balance, ignoring viscous dissipation, to estimate the contact angle from the meniscus curvature and changes in interfacial areas and saturation. We apply these methods to characterize wettability on pore-scale images of two- and three-phase flow. We also discuss the implications of the results for recovery and storage applications.

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Development of a method for multielemental determination in water by EDXRF with radioisotopic source of 238Pu.

Brazilian Journal of Radiation Sciences ◽

10.15392/bjrs.v7i2a.627 ◽

2019 ◽

Vol 7 (2A) ◽

Author(s):

Camilo Fuentes Serrano ◽

Juan Reinaldo Estevez Alvares ◽

Alfredo Montero Alvarez ◽

Ivan Pupo Gonzales ◽

Zahily Herrero Fernandez ◽

...

Keyword(s):

Thin Layer ◽

Expanded Uncertainty ◽

Considerable Decrease ◽

X Ray ◽

Precipitation Efficiency ◽

Method Of Determination ◽

Sensitivity Curves ◽

Order Of Magnitude ◽

Metrological Parameters

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of 238Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidinedithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of 238Pu instead of 109Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L).

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