Field test for determining concentration of emulsifiers in drilling fluids using dyes

Abstract

Oil-based drilling fluids can include an emulsifier to help stabilize the phases of the fluid. During repeated use, the amount of free emulsifier can become depleted. A field test can be used to determine the amount of free emulsifier in the fluid. Top oil from an aliquot from the fluid can be placed into a testing vial and mixed with an aqueous solution including a dye and optionally a pH adjuster or an acid or acidic buffer to facilitate dye transfer from the aqueous phase to the oil phase. The amount of dye transferred to the oil phase can be used to determine the amount of free emulsifier. Reference samples can be prepared with a known concentration of the emulsifier to visually compare the amount of dye transfer in the testing vial to the reference sample. Spectroscopy can also be used to compare the dye transfer in the test vial to the reference sample.

Dependencies are inferred from the claim text.