Characterization of Local Clay for Drilling Mud Production

Abstract

Oil companies’dealing with drilling operations in Nigeria often spends millions of dollars in importation of bentonite for its operations as a result of its importance and high demand. As a result of this, attempt to source for local substitute has been initiated, which if successful would save the nation from this huge capital flight. In this study, a sample of Umuna local clay deposit was evaluated for drilling fluid application. The viscosity and filtration loss was analyzed and it’s far below that of the imported bentonite. The properties of the local clay was improved by addingmaterials such as HV-CMC, Drispac polymer and bentonite extenders to the formulated mud to enhance its viscosity and filtration loss Also the shearing speed was increased, but the used speed is limited to practical shearing speed. Theclay yield and characterization of the beneficiated samples show that the treated local clay is slightly comparable to the imported bentonite. The Calcium Exchange Capacity (CEC) result for the clay samples fall within the 70 – 150 Meq/100g. This result further suggests that the analyzed clay is of montimorillonite family, with traces of illite which is good for drilling mud production. The obtained results from this study indicates that the filtration loss and plastic viscosity for the analyzed clay samples were generally far from comparing with the imported bentonite, but through beneficiation, they were able to compare with the imported bentonite.