Critical analysis of uncertainties during particle filtration

Abstract

Using the law of propagation of uncertainties we show how equipment- and measurement-related uncertainties contribute to the overall combined standard uncertainties (CSU) in filter permeability and in modelling the results for polystyrene latex microspheres filtration through a borosilicate glass filter at various injection velocities. Standard uncertainties in dynamic viscosity and volumetric flowrate of microspheres suspension have the greatest influence on the overall CSU in filter permeability which excellently agrees with results obtained from Monte Carlo simulations. Two model parameters “maximum critical retention concentration” and “minimum injection velocity” and their uncertainties were calculated by fitting two quadratic mathematical models to the experimental data using a weighted least squares approximation. Uncertainty in the internal cake porosity has the highest impact on modelling uncertainties in critical retention concentration. The model with the internal cake porosity reproduces experimental “critical retention concentration vs velocity”-data better than the second model which contains the total electrostatic force whose value and uncertainty have not been reliably calculated due to the lack of experimental dielectric data.

Experimental study of colloidal flow in porous media at high velocities

“…Colloidal suspension was sequentially injected until the apparent permeability stabilization within its experimental uncertainty. [30] This was achieved after five consecutive injections schematically indicated by an arrow between points 0 and 1 in Fig. 2.…”

“…A different approach was employed for higher flow rates: The system was tested at a control flow rate (10 mL/min) after each of the following flow rates-20, 30, 60, and 100 mL/min to observe a non-damaging effect of high velocity flow on a porous medium. Stabilization of permeability within its experimental uncertainty of 3.09% [30] was achieved within 2 min from the beginning of an experiment at each flow rate. The following experimental parameters were recorded with 2 min intervals: pressure drop across the filter, overburden pressure, backup pressure, and temperature of the solution.…”

“…[29] EXPERIMENTAL PROCEDURE High velocity particle attachment was studied using realtime liquid permeability monitoring apparatus described in detail elsewhere. [30] The filter (1; Fig. 1) was placed inside a rubber sleeve (2) in the high-pressure core holder (3; 'TEMCO', Core Laboratories, Houston, Texas, USA).…”