EVALUATION OF SELECTED LOCAL MATERIALS FOR FORMULATION OF DRILLING FLUID

ABSTRACT

This research work examined if probable clay from the Delta State, Nigerian village of Uwheru might be used to make water-based drilling mud and also to see if it can be improved on by using local addictives such as sweet potato starch and soda ash. The clay's properties were assessed and contrasted with those of imported bentonite, the preferred clay for drilling operations, before waterbased mud was created from it. The findings indicate that, when compared to those of bentonite, the formulated drilling fluid's rheological characteristics and pH values differed significantly. This is due to a lack of sodium cations (Na++), which prevents clay from attracted to water and inhibits its tendency to swell. The mud's pH increased by 70% from 5.65 to 9.60 after being beneficiated with soda ash (Na2CO3) and sweet potato starch at concentrations of 5.0g and 50g, respectively, to 350mL of the local mud. Meanwhile, the apparent viscosity, yield point, and plastic viscosity increased by 229%, 200%, and 250%, respectively. The clay density increased by 7% from an initial value of 8.60lb/gal to 9.20lb/gal with the addition of barite (BaSO4) content of 10g to 350mL of the formulated drilling fluid. As a result when improved with soda ash (Na2CO3) and sweet potato starch, the Uwheru clay displays good rheological properties that would xii compare favorably with those of bentonite at high concentrations. In other words, Uwheru clay could be used to create a drilling fluid.