Emulsifiers Used in Designing Emulsion Based Drilling Fluids

Al-Yami AS, Wagle Vikrant*,

Abstract

Emulsion drilling fluids have shown improved performance compared to water based fluids in the field. However, emulsion stability which is indicated by the resistance of the chemical emulsifier against contaminant (anhydrite, cement, sodium chloride, ions of calcium and magnesium and others) is always a concern. Concentration will vary from one emulsifier to another depending on the chemical composition of the emulsifier. To the best of authors’ knowledge this is the first paper that details different chemistry of emulsifiers used in oil based drilling fluids. The paper details also basics about emulsifier interaction with oil and water phases as well as the factors we need to consider in emulsifier selection. Emulsion types and stability are also investigated in this paper. Different options of emulsifiers are also detailed with examples of oil based fluids utilized for typical drilling operations.