US Patent 7455783 Method for centrifugal separation enhancement

A method for removing low gravity solids from an oil-based drilling fluid includes directing the drilling fluid into a first inlet of a first line in fluid communication with a centrifuge, injecting steam into the drilling fluid through a second inlet in the first line, wherein the second inlet is upstream from the centrifuge, directing the commingled drilling fluid and steam into the centrifuge, rotating the centrifuge at a rotational speed sufficient to separate solids from liquids, collecting solids from a solids discharge, and collecting effluent from an effluent outlet, wherein the effluent has low gravity solids in an amount less than 1.5%.