| abstract |
A method for processing a return oil based drilling fluid includes centrifuging a phase of fluids primarily at a first rate and separating the phase primarily of fluids in a first effluent and a first residual, centrifuging the first effluent at a second rate and separating the first effluent in a second effluent and a second residual, and centrifuge the second effluent at a third speed and separate the second effluent into a third effluent and a third residual; a surfactant, a polymer, combinations of surfactants and polymers and / or a wash water may be added to one or more of the return oil base drilling fluid, the primarily fluid phase, the primarily solids phase, the first effluent , the second effluent and the third effluent. |