Patent ID: 7913776

Claim:
A process for recovering an oil-based drilling fluid from used oil-based drilling mud, the used oil-based drilling mud having drilling cuttings material and a fluid phase, the fluid phase having high gravity solid material and low gravity solid material, the process comprising: separating the drilling cuttings material from the fluid phase of the used oil-based drilling mud, the step of separating the drilling cuttings material from the fluid phase of the used oil-based drilling mud further comprising screening the used oil-based drilling mud; separating the high gravity solid material from the fluid phase of the used oil-based drilling mud the step of separating the high gravity solid material from the fluid phase of the used oil-based drilling mud at least one, further comprising centrifuging the used oil-based drilling mud, such centrifugation discharging a first overflow fraction and a first underflow fraction, the first overflow fraction comprising an emulsion and low gravity solid material and the first underflow fraction comprising high gravity solid material; and separating the low gravity solid material from the fluid phase of the used oil-based drilling mud, the step of separating the low gravity solid material from the fluid phase of the used oil-based drilling mud further comprising: exothermically reacting the first overflow fraction such that the emulsion and at least some of the low gravity solid material is separated; and centrifuging the reacted first overflow fraction such that a second overflow fraction is discharged, the second overflow fraction substantially comprising the emulsion and a reduced amount of low gravity solid material, and further such that a second underflow fraction is discharged, the second underflow fraction comprising the separated low gravity solid material.