Centrifugal separator

In a centrifugal separator for a mixture which may include oil, water, gas and/or solids, the combination of:

• housing means;
• a rotor rotatable in said housing means and having an inner rotor chamber and an outer rotor chamber encircling said inner rotor chamber;
• mixture delivery means for delivering the mixture to said inner rotor chamber;
• the periphery of said inner rotor chamber having discharge ports communicating with said outer rotor chamber;
• the periphery of said outer rotor chamber having discharge ports communicating with said inner housing;
• water supply means for delivering water to said outer rotor chamber at a rate at least equal to the discharge capacity of said discharge ports in said outer rotor chamber at a given rotor speed;
• excess-water discharge means on said rotor for discharging any excess water delivered to said outer rotor chamber into said housing means so as to maintain a substantially constant pressure in said outer rotor chamber at said given rotor speed;
• and
• oil discharge means for removing oil from said inner rotor chamber under pressure.

In a centrifugal separator for a mixture which may include oil, water, gas and/or solids, the combination of:

• housing means including inner and outer housings;
• a rotor rotatable in said housing means and having an inner rotor chamber and an outer rotor chamber encircling said inner rotor chamber;
• mixture delivery means for delivering the mixture to said inner rotor chamber;
• the periphery of said inner rotor chamber having discharge ports communicating with said outer rotor chamber;
• the periphery of said outer rotor chamber having discharge ports communicating with said inner housing;
• water supply means for delivering water to said outer rotor chamber at a rate at least equal to the discharge capacity of said discharge ports in said outer rotor chamber at a given rotor speed so as to maintain a substantially constant pressure in said outer rotor chamber at said given rotor speed, said water supply means including a pump having its inlet in communication with said inner housing adjacent the bottom thereof;
• excess-water discharge means on said rotor for discharging any excess water delivered to said outer rotor chamber into said inner housing;
• oil discharge means for removing oil from said inner rotor chamber;
• a water outlet communicating with said inner housing;
• a water outlet valve controlling said water outlet;
• and
• means controlling said water outlet valve for maintaining a predetermined water level in said inner housing.

In a centrifugal separator for a mixture which may include oil, water, gas and/or solids, the combination of:

• housing means including inner and outer housings;
• a rotor rotatable in said housing means and having an inner rotor chamber and an outer rotor chamber encircling said inner rotor chamber;
• mixture delivery means for delivering the mixture to said inner rotor chamber;
• the periphery of said inner rotor chamber having discharge ports communicating with said outer rotor chamber;
• the periphery of said outer rotor chamber having discharge ports communicating with said housing means;
• water supply means for delivering water to said outer rotor chamber at a rate at least equal to the discharge capacity of said discharge ports in said outer rotor chamber at a given rotor speed so as to maintain a substantially constant pressure in said outer rotor chamber at said given rotor speed;
• excess-water discharge means on said rotor for discharging any excess water delivered to said outer rotor chamber into said inner housing;
• and
• oil discharge means for removing oil from said inner rotor chamber;
• and wherein said inner rotor chamber is provided with:
• gas discharge means communicating with said outer housing;
• excess-oil outlet means also communicating with said outer housing.

In a centrifugal separator for a mixture of fluids of different densities, the combination of:

• a. housing means;
• b. a rotor rotatable in said housing means and having an inner rotor chamber and an outer rotor chamber encircling said inner rotor chamber;
• c. mixture delivery means for delivering the mixture to said inner rotor chamber;
• d. the periphery of said inner rotor chamber having discharge ports communicating with said outer rotor chamber;
• e. the periphery of said outer rotor chamber having discharge ports communicating with said housing means;
• f. an overflow weir on the outer rotor chamber for discharging excess fluid of greatest density into said housing means;
• g. supply means for delivering fluid of the greatest density to said outer rotor chamber at a rate at least equal to the discharge capacity of said discharge ports in said outer rotor chamber at a given rotor speed so as to keep the outer rotor chamber filled to the radius of the weir and maintain a substantially constant pressure in said outer rotor chamber at said given rotor speed;
• and
• h. discharge means for removing fluid of a lesser density from said inner rotor chamber under pressure.

A three phase separator for a mixture which may include oil, water, gas and/or solids comprising:

• a rotor having a rotor chamber;
• means for delivering the mixture to the rotor chamber;
• discharge port means on the periphery of the rotor chamber for discharging water and/or solids from the periphery of the rotor chamber;
• a first weir means relatively nearer the axis of rotation of the rotor for passage of gas and overflow of excess oil;
• a second weir means relatively further from the axis of rotation of the rotor for overflow of excess water;
• water passage means between the second weir means and the periphery of the rotor chamber;
• means for adding water into the water passage means adjacent the second weir means for keeping the water passage means filled with water during rotation of the rotor for maintaining a constant pressure near the periphery of the rotor corresponding to the head of water in the water passage means between the second weir means and the periphery of the rotor chamber thereby defining a substantially constant oil-water interface radial position in the rotor chamber between the second weir means and the periphery of the rotor chamber;
• a stationary pitot tube in the rotor chamber having an inlet in a radial position between the first weir means and the oil-water interface for withdrawing oil under pressure.