seen forhindra mix up of drilling mud and cementslam at the completion of borrhal lined in the ground with anvendning of drilling mud and skiljevetska intended for anvendning hervid

摘要

A spacer fluid emulsion comprising approximately equal volume parts of a hydrocarbon oil and fresh water, and containing from about 15 pounds per barrel to about 40 pounds per barrel of an emulsifier, about 0.5 pounds per barrel to about 10 pounds per barrel of a strong surfactant-dispersant, and a weighting material in an amount effective to impart a density to the spacer fluid of from about 8 pounds per gallon to about 20 pounds per gallon. The emulsifier used comprises an oleyl amide, preferably in admixture with oleic acid and dimerized oleic acid, adsorbed on a solid carrier selected from the group consisting of lime, as herein defined, and diatomaceous earth. The surfactant-dispersant preferably comprises a mixture of about equal weight parts of waste sulfite liquor, and the reaction product derived from the reaction of oleyl chloride and n-methyltaurine. The invention is further directed to methods of using such spacer fluids between cement and drilling fluids during well completions.