Centrifugal separator

Abstract

A three-phase centrifugal separator for a mixture which may include oil, water, gas and/or solids. A rotor is provided with an inner rotor chamber encircled by an outer rotor chamber, the mixture being delivered to the inner rotor chamber wherein it is centrifugally separated into an inner gas phase encircling the rotor axis, an annular intermediate oil phase encircling the gas phase, and an annular outer water and solids phase encircling the oil phase. Water and solids are discharged into the outer rotor chamber through discharge ports in the periphery of the inner rotor chamber, and are subsequently discharged into an enclosing housing means through discharge ports in the periphery of the outer rotor chamber. A water supply means delivers water to the outer rotor chamber at a rate at least equal to, and preferably considerably in excess of, the discharge capacity of the discharge ports in the outer rotor chamber at a given rotor speed so as to maintain a substantially constant pressure in the outer rotor chamber at such rotor speed. Means are provided for removing oil and gas from the corresponding phases in the inner rotor chamber.