SPACER FLUID HAVING SIZED PARTICULATES AND METHODS OF USING THE SAME

摘要

A spacer fluid contains one or more hydratable polymeric viscosifying agents having a particle size distribution such that a minimum of 90% of the particulates are retained on a 20 mesh screen. The spacer fluid may further contain one or more surfactants, viscosity thinners, organic solvents, weighting materials, suspending agents and antifoaming agents. The spacer fluid may be used to position a first fluid into a wellbore annulus of a wellbore containing a second fluid. The spacer fluid may further be used to fluidly isolate at least a portion of a wellbore annulus in a wellbore containing an oil-based drilling mud and an aqueous cement slurry.

主权项

1. A spacer fluid for separating a drilling mud and an aqueous cement slurry in a wellbore comprising particulates of a hydratable polymeric viscosifying agent having a particle size distribution such that a minimum of 90% of the particulates are retained on a 20 mesh screen.