Evaluation of Filtration Properties of Clay Suspensions under Different Thermic Conditions

In clay suspensions designed for drilling, the sodic bentonite clay is commonly chosen for its better hydration capacity compared to the other kinds. The sodium bentonite clay is essentially composed by montmorilonite, a clay mineral that belongs to the group of smectites. This work aims to evaluate the behavior of clay suspensions under different thermic conditions. For that, were studied suspensions prepared with sodium bentonite clay, in concentrations varying between 2.5% and 6.4%, under different temperatures and also types of aging. The suspensions were tested based on a matrix of experimental planning. The filtration properties were determined by the filtrate volume, the relation of filtrate volume with time of filtration, the mudcake thickness and the permeability of the mudcake. The results exhibited that the high temperature promotes a gelification state of the suspensions, being therefore responsible for the high values of the filtration properties.