EVALUATION OF THE RHEOLOGICAL PROPERTIES OF WATER BASED DRILLING FLUID

ABSTRACT

In this study, the effect of the blend of eggshell and snail shell (which are food wastes) as local eco-friendly additives on the rheological properties (plastic viscosity, yield point, gel strength and apparent viscosity) of water based mud was evaluated. The control mud sample was formulated with 350ml of tap water and 22.5g of bentonite. Six more samples were also prepared using the same quantity of water and bentonite with varying weight proportions of the eggshell and snail shell blend – 2g, 5g, 10g, 15g, 20g and 30g (i.e 0.6, 1.4, 2.9, 4.3, 5.7 and 8.6% by volume of water). The experiment was conducted at room temperature. The result showed that increase in plastic viscosity of the control mud was obtained at 15g, 20g and 30g of the local additive which increased it by 1cp, 2cp and 3cp respectively. The yield point values gave a fluctuating trend, increasing and decreasing with increase in concentration of the local blend. The trend observed for the gel strength values at 10sec and 10min was an increase in the gel strength with increase in concentration of the local blend and likewise for the apparent viscosity values except for the decrease by 0.5cp of the apparent viscosity observed with 30g of the local additive. Overall, there was a general increase in the rheological parameters of the bentonite mud with increase in the concentration of the eggshell snail shell blend. Hence showing some potential to be used as a rheological property modifier in water based mud.