Abstract
This paper describes a numerical filtration model validated by data obtained from an experimental dynamic filtration loop. The model predicts the filtercake buildup and filtrate flow rate in the drilling process using non-Newtonian muds. It is also able to calculate filtercake properties like permeability and thickness. The equations, written in cylindrical coordinate, are based on the motion and mass conservation equation of the fluid described by Darcy's law. In addition, the permeability and porosity are correlated to the filtercake pressure. The point at which the mud fluid shear rate and the filtercake shear strength are equal defines the filtercake thickness.
In the dynamic filtration loop there is a tube with a permeable wall where the carbonate suspension of different sized particles is filtrated. The suspension is homogenized in a tank mixer and pumped using a positive displacement pump. The filtration model was validated through experimental data. In this paper, we discuss the effects of cross-flow velocity and filtration pressure on the filtrate rate and filtercake buildup. The simulated data of filtrate rate and filtercake thickness agreed well with the experimental data.