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You searched for subject:(porous medium filtration). Showing records 1 – 2 of 2 total matches.

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University of Oxford

1. Krupp, Armin Ulrich. Mathematical modelling of membrane filtration.

Degree: PhD, 2017, University of Oxford

In this thesis, we consider four different problems in membrane filtration, using a different mathematical approach in each instance. We account for the fluid-driven deformation of a filtercake using nonlinear poroelasticity in Chapter 2. By considering feeds with very high and very low particle concentrations, we introduce a quasi-static caking model that provides a suitable approximation to the full model for the physically realistic concentration regimes. We illustrate the agreements and differences between our model and the existing conventional cake-filtration law. In Chapter 3, we introduce a stochastic model for membrane filtration based on the quantised nature of the particles and show how it can be applied for feeds with different particle types and membranes with an interconnected pore structure. This allows us to understand the relation between the effects of clogging on the level of an individual pore and on the macroscopic level of the entire membrane. We conclude by explaining the transition between the discrete and continuous model based on the Fokker – Planck equation. In Chapter 4, we consider the inverse problem of determining the underlying filtration law from the spreading speed of a particle-laden gravity current. We first couple the theory of gravity currents with the stochastic model developed in Chapter~3 to determine a filtration law from a given set of experiments. We then generalise this idea for the porous medium equation, where we show that the position of the front follows a power law for the conventional filtration laws, which allows us to infer the clogging law in certain instances. We conclude the thesis by showing in Chapter 5 how we can combine experimental measurements for the clogging of a depth filter and simple fluid dynamics to accurately predict the pressure distribution in a multi-capsule depth filter during a filtration run.

Subjects/Keywords: Mathematics; Porous Media; Porous Medium Equation; Membrane Filtration; Gravity Current; Mathematical Modelling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Krupp, A. U. (2017). Mathematical modelling of membrane filtration. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:ae6dd9e4-a862-4476-a8d9-35156848297f ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757750

Chicago Manual of Style (16th Edition):

Krupp, Armin Ulrich. “Mathematical modelling of membrane filtration.” 2017. Doctoral Dissertation, University of Oxford. Accessed June 25, 2019. http://ora.ox.ac.uk/objects/uuid:ae6dd9e4-a862-4476-a8d9-35156848297f ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757750.

MLA Handbook (7th Edition):

Krupp, Armin Ulrich. “Mathematical modelling of membrane filtration.” 2017. Web. 25 Jun 2019.

Vancouver:

Krupp AU. Mathematical modelling of membrane filtration. [Internet] [Doctoral dissertation]. University of Oxford; 2017. [cited 2019 Jun 25]. Available from: http://ora.ox.ac.uk/objects/uuid:ae6dd9e4-a862-4476-a8d9-35156848297f ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757750.

Council of Science Editors:

Krupp AU. Mathematical modelling of membrane filtration. [Doctoral Dissertation]. University of Oxford; 2017. Available from: http://ora.ox.ac.uk/objects/uuid:ae6dd9e4-a862-4476-a8d9-35156848297f ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.757750


Northeastern University

2. Sun, Jianfeng. Solid mechanics in colloidal and bacterial filtration.

Degree: PhD, Department of Mechanical and Industrial Engineering, 2017, Northeastern University

Microbial and particle transportation and adhesion in porous media in electrolytic solutions is fundamental in many fields related to water treatment, drug delivery and human health. This is a complex multi-physics process which includes, but not limited to, fluid mechanics, microbial properties, surface adhesion and aqueous environments. The conventional, empirically-driven approach is based on a flow-through sand-packed column test. Although it is widely applied to predict filtration efficiency, the fundamental science and contribution of individual factors in this problem are still missing-for example, flow condition, salt concentration and microbial properties.; This dissertation addresses this problem by developing a new microfluidic test method and a theoretical model based on contact mechanics. The new microfluidic test simplifies the physics behind microbial/colloidal filtration, and allows us to focus on the surface attachment/detachment due to inter-surface and hydrodynamic interactions. Filtration efficacy was directly measured using this new microfluidic test. The results of the tests were then compared with the conventional flow-through column test. The two show a good agreement with each other. This implies that surface adsorption is the dominant filtration mechanism in the column test. The coupled effect of flow rate, salt concentration and microbial properties were analysed using the classical DLVO theory, fluid mechanics and contact mechanics. The fundamental physics that control the microbial/colloidal attachment were suggested.; We further developed a theoretical model for microbial filtration in a porous medium based on a moment balance method. The fate of an adhered microbial cell after collision with a sand collector was determined by competition between the adhesive moment due to the surface adhesion and the detachment moment due to hydrodynamic interaction. The new model takes into account the effects of flow condition, salt concentration and bacterial micro-properties. The theoretical results agree well with the experimental results, and we believe the new model captures the fundamentals of the problem.; In summary, this dissertation shows the significance of fluid and contact mechanics in microbial/colloidal adhesion and transportation. It reveals the underlying physics and provides a valuable tool-the microfluidic test-for studying the microbial/colloidal filtration problem.

Subjects/Keywords: capillary; colloid and bacteria; microfluidics; porous medium filtration; solid mechanics; surface adhesion

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Sun, J. (2017). Solid mechanics in colloidal and bacterial filtration. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20263653

Chicago Manual of Style (16th Edition):

Sun, Jianfeng. “Solid mechanics in colloidal and bacterial filtration.” 2017. Doctoral Dissertation, Northeastern University. Accessed June 25, 2019. http://hdl.handle.net/2047/D20263653.

MLA Handbook (7th Edition):

Sun, Jianfeng. “Solid mechanics in colloidal and bacterial filtration.” 2017. Web. 25 Jun 2019.

Vancouver:

Sun J. Solid mechanics in colloidal and bacterial filtration. [Internet] [Doctoral dissertation]. Northeastern University; 2017. [cited 2019 Jun 25]. Available from: http://hdl.handle.net/2047/D20263653.

Council of Science Editors:

Sun J. Solid mechanics in colloidal and bacterial filtration. [Doctoral Dissertation]. Northeastern University; 2017. Available from: http://hdl.handle.net/2047/D20263653

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