COMPOSITIONS AND METHODS FOR CLEANING A WELLBORE PRIOR TO CEMENTING

摘要

Single-phase microemulsions, comprising a solvent, a surfactant blend and a carrier fluid, are effective spacer fluids for use during cementing operations. The solvent may be selected from the group consisting of monoterpenes, diterpenes, and alkyl or aryl esters of short-chain alcohols. The surfactant blend comprises a water-wetting surfactant or nonionic surfactant, a co-surfactant and an oil-solubilizing surfactant. The carrier fluid is aqueous. The solvent and surfactant blend are combined with the carrier fluid to produce the well-treatment microemulsion.