Abstract: An organic based emulsion-breaking formulation for use in treating well bores drilled in oil-bearing mud that is not eco-toxic and is optimally compatible with formation fluids comprises: as the emulsion-breaking agent, at least one constituent selected from non-ionic amphiphilic compositions obtained by reacting at least one polymerized vegetable oil with at least one aminoalcohol and alkyl esters (for example C1 to C8) of fatty acids derived from natural, vegetable or animal oils; optionally, at least one wetting agent selected from anionic surfactants; and optionally at least one solvent; the assembly being as a mixture in an organic base. Such a formulation can be weighted by mineral fillers.

Abstract: A method of breaking oil-in-water and water-in-oil emulsions in crude oil processing systems in which copolymers incorporating a hydrophilic cationic monomer subunit and a lipophilic nonionic monomer subunit or dispersions or emulsions of cationic polymers and obverse demulsifiers are employed.