Abstract: A method for recycling an invert emulsion based drilling fluid, in which the invert emulsion based drilling fluid includes an oil component and an aqueous component. The method includes: mixing the invert emulsion drilling fluid with a emulsion clearing agent, wherein the emulsion clearing agent is a mixture of an anionic tensid and a non-ionic tensid; and separating the oil component of the invert emulsion drilling fluid from the aqueous component of the invert emulsion drilling fluid. The method preferably utilizes an emulsion breaking agent that is a combination of an anionic tensid, a non-ionic tensid and an alkyl polyglycoside tensid.

Abstract: Polymer compositions made by reacting a polyol with an aromatic hydrocarbon containing only a single reactive functionality have been discovered to be useful demulsifiers for crude oil compositions. The aromatic hydrocarbon should have at least one aryl group and only one functionality reactive with a hydroxyl. The polyol may optionally be crosslinked prior to reaction with the aromatic hydrocarbon, and the crosslinking agent may be a diepoxide.