Evaluating the Performance of Local Anionic Emulsifier as a Possible Emulsifier for Synthetic-Based Mud System for Drilling Operations

Abstract

In the process of formulating oil-based muds, emulsifiers or surfactants are added to help build a strong oil-water emulsion. Currently, all the emulsifiers used in mud formulation in Ghana are imported increasing drilling cost. This also do not promote the local content and local participation policy of the country in the oil and gas sector. There are equally potential local emulsifiers that could be used in these mud formulations to reduce cost. This research, therefore, evaluated the performance of local anionic surfactant as a possible emulsifier for an ester-based oil mud system for drilling operations. A Synthetic-Based Mud (SBM) was formulated with varying concentrations of both local (L) and commercial (C) emulsifiers from 0% to 100% at a step of 25% after which their rheological properties evaluated. The rheological properties were evaluated for unaged samples at temperatures of 80 °F, 120 °F, 180 °F and aged samples at a temperature at 180 °F. The performances of the mud samples were tested using Gel Strength at 10 seconds and 10 minutes, Plastic Viscosity, Yield Point and pH at each varied concentration of emulsifier following closely the American Petroleum Institute (API) standard test procedures. The overall performances of the mud samples in order of descending were; BL100% > AC100% > EC25%L75% > CC50%L50% > DC75%L25%. It was observed that the local emulsifier performed equally well and even better than the commercial emulsifiers at the test conditions presenting the local emulsifier as a potential emulsifier for the formulation of SBMs for the oil and gas industry.