Method for quantitative analysis of a distribution of solid particles of a suspension invaded in a porous medium during filtration

Abstract

Solid particles are colored with a cationic dye and at least three calibration standards having different known mass concentrations of the colored particles are prepared. A digital analysis of the images of the calibration standards is carried out based on an additive RGB color model and intensity distribution profiles of red, green and blue colors are obtained for each calibration standard. A single norm function is selected to characterize quantitatively changes in the red, green and blue colors in all calibration standards. A single calibration curve is obtained by comparing values of the selected norm function for each calibration standard with a known mass concentration of the colored particles in this calibration standard. A suspension of the colored solid particles is injected through a porous medium sample and the sample is split into two parts along a suspension flow direction. A digital analysis of an image of the split of the porous medium sample is carried out based on the additive RGB color model and a two-dimensional intensity distribution of red, green and blue colors in the sample split is obtained. Reference intensities of red, green and blue colors are determined and based on the obtained two-dimensional intensity distribution of red, green and blue colors in the obtained image of the sample split, using the reference intensities of red, green and blue colors, the selected norm function and the obtained calibration curve a two-dimensional distribution of the mass concentration of the colored suspension solid particles is determined.