USE OF SELECTED ESTER OILS IN WATER-BASED DRILLING FLUIDS OF THE O/W EMULSION TYPE AND CORRESPONDING DRILLING FLUIDS WITH IMPROVED ECOLOGICAL ACCEPTABILITY

摘要

The use is disclosed of water-dispersible esters, which are fluid or atleast plastically deformable at working temperature and have flashpoints of at least 80°C, from saturated and/or unsaturated carboxylicacids with up to 36 carbon atoms and mono- and/or polyhydric aloohols,as at least the main constituent of the dispersed oil phase ofwater-based O/W-emulsion drilling fluids which are suitable for theenvironmentally friendly development of geological formations and whichcontain, if desired, insoluble, finely particulate weighting agents forthe formation of water-based O/W-emulsion drilling mode and/or furtheradditives, such as emulsifiers, fluid-loss additives, wetting agents,alkali reserves and/or auxiliary substances for the inhibition ofdrilled rock of high water-sensitivity.