Subterranean fluids having improved environmental characteristics and methods of using these fluids in subterranean formations

摘要

Subterranean fluids are provided that have improved environmental characteristics, and more particularly, subterranean fluids are provided that include a hydraulic cement in an invert emulsion. Methods of using such fluids in subterranean operations also are provided. An example of a method is a method of using a fluid in a subterranean formation. An example of a composition is a fluid comprising a hydraulic cement and an invert emulsion of an oleaginous fluid, a nonoleaginous fluid, and an emulsifying surfactant, wherein the emulsifying surfactant: has an LC₅₀ or EC₅₀ that is greater than about 10 milligrams/liter with respect to Skeletonema costatum, Acartia tonsa, Scopthalmus maximus (juvenile), or Corophium volutator; and demonstrates a biodegradability of: greater than about 70% biodegradation in 28 days when tested according to method OECD 301A or 301E; or greater than about 60% biodegradation in 28 days when tested according to method OECD 301B, 301C, 301F, or 306.