| abstract |
A non-damaging well completion and workover fluid comprising a dispersion of finely divided, slowly oil-soluble, water-insoluble solid particles in an aqueous salt solution containing chrome lignite, hydroxyethyl cellulose and xanthan gum. The density of the fluid is controlled by varying the concentration of salt dissolved in the solution. The finely divided solid particles consist of a homogeneous solid solution of (1) wax; (2) an oilsoluble surface active glyceryl or sorbitan partial ester of a saturated higher fatty acid; (3) a water-dispersible surface active polyethylene glycol monoester of a saturated higher fatty acid; (4) an ethylene/vinyl acetate copolymer, and (5) a fatty alcohol. |