Fractionator reflux pump method and apparatus

Claim 1

An apparatus comprising a fractional distillation column, first conduit means for introducing into said column a feed stream to be fractionated, second conduit means connected in communication with a lower portion of said column for withdrawal of a bottoms product stream, a condenser having an inlet and an outlet, third conduit means connected between an upper portion of said column and said inlet of said condenser, an accumulator having an inlet, a liquid outlet and a vapor outlet, fourth conduit means connected between said condenser outlet and said accumulator inlet, fifth conduit means connected in communication with said accumulator vapor outlet, first valve means operatively positioned in said fifth conduit means, means for manipulating said first valve means, sixth conduit means connected in communication with said accumulator liquid outlet for withdrawal of an overhead product stream, second valve means operatively positioned in said sixth conduit means, means for manipulating said second valve means, a pump having an inlet and an outlet, a means connected between said pump inlet and an upper portion of said column for withdrawal of a fluid distillate stream, a cooler having an inlet and an outlet, seventh conduit means connected between said cooler inlet and said pump outlet, a conduit junction having an inlet, a first outlet and a second outlet, eighth conduit means connected between said conduit junction inlet and said cooler outlet for withdrawal of a cooled fluid distillate stream, ninth conduit means connected between said conduit junction first outlet and an upper portion of said column for the return of said cooled fluid distillate stream to said column, third valve means operatively positioned in said ninth conduit means, means for manipulating said third valve means, a tenth conduit means connected between said conduit junction second outlet and said pump inlet, fourth valve means operatively positioned in said tenth conduit means, and means for manipulating said fourth valve means.

Claim 2

An apparatus comprising a fractional distillation column, first conduit means for introducing into said column a feed stream to be fractionated, second conduit means connected in communication with a lower portion of said column for withdrawal of a bottoms product stream, a condenser having an inlet and an outlet, third conduit means connected between an upper portion of said column and said inlet of said condenser, an accumulator having an inlet, a liquid outlet and a vapor outlet, fourth conduit means connected between said condenser outlet and said accumulator inlet, fifth conduit means connected in communication with said accumulator vapor outlet, first valve means operatively positioned in said fifth conduit means, means for manipulating said first valve means, sixth conduit means connected in communication with said accumulator liquid outlet for withdrawal of an overhead product stream, second valve means operatively positioned in said sixth conduit means, means for manipulating said second valve means, a pump having an inlet and an outlet, a means connected between said pump inlet and an upper portion of said column for withdrawal of a fluid distillate stream, a cooler having an inlet and an outlet, seventh conduit means connected between said cooler inlet and said pump outlet, a conduit junction having an inlet, a first outlet and a second outlet, eighth conduit means connected between said conduit junction inlet and said cooler outlet for withdrawal of a cooled fluid distillate stream, ninth conduit means connected between said conduit junction first outlet and an upper portion of said column for the return of said cooled fluid distillate stream to said column, third valve means operatively positioned in said ninth conduit means, means for manipulating said third valve means, a tenth conduit means connected between said conduit junction second outlet and said pump inlet, fourth valve means operatively positioned in said tenth conduit means, and means for manipulating said fourth valve means.

Claim 18

A method comprising passing a feed stream to be fractionated into a fractional distillation zone, withdrawing a bottoms product stream from a lower portion of said fractional distillation zone, withdrawing a vaporous overhead stream from an upper portion of said fractional distillation zone, passing said vaporous overhead stream into a condensing zone and therein at least partially condensing said vaporous overhead stream into a condensate, withdrawing said condensate along with any uncondensed portion of said vaporous overhead stream, passing said condensate and said any uncondensed portion of said vaporous overhead stream into an accumulation zone, withdrawing condensate from said accumulation zone as an overhead product stream, withdrawing an uncondensed portion of said vaporous overhead stream from said accumulation zone, passing a fluid distillate stream from an upper portion of said fractional distillation zone into a pumping zone and therein increasing the pressure of said fluid distillate stream, withdrawing said fluid distillate stream of increased pressure from said pumping zone, passing the thus withdrawn fluid distillate stream into a cooling zone and therein cooling said fluid distillate stream, withdrawing the thus cooled fluid distillate stream from said cooling zone, passing the thus withdrawn cooled fluid distillate stream to an upper portion of said fractional distillation zone as reflux only when the rate at which said fluid distillate stream is withdrawn from an upper portion of said fractional distillation zone is greater than or substantially equal to the rate at which said cooled fluid distillate stream is withdrawn from said cooling zone, and passing the thus withdrawn cooled fluid distillate stream back to said pumping zone when the rate at which said fluid distillate stream is withdrawn from an upper portion of said fractional distillation zone is substantially less than the rate at which said cooled fluid distillate stream is withdrawn from said cooling zone.

Claim 19

A method comprising passing a feed stream to be fractionated into a fractional distillation zone, withdrawing a bottoms product stream from a lower portion of said fractional distillation zone, withdrawing a vaporous overhead stream from an upper portion of said fractional distillation zone, passing said vaporous overhead stream into a condensing zone and therein at least partially condensing said vaporous overhead stream into a condensate, withdrawing said condensate along with any uncondensed portion of said vaporous overhead stream, passing said condensate and said any uncondensed portion of said vaporous overhead stream into an accumulation zone, withdrawing condensate from said accumulation zone as an overhead product stream, withdrawing an uncondensed portion of said vaporous overhead stream from said accumulation zone, passing a fluid distillate stream from an upper portion of said fractional distillation zone into a pumping zone and therein increasing the pressure of said fluid distillate stream, withdrawing said fluid distillate stream of increased pressure from said pumping zone, passing the thus withdrawn fluid distillate stream into a cooling zone and therein cooling said fluid distillate stream, withdrawing the thus cooled fluid distillate stream from said cooling zone, passing the thus withdrawn cooled fluid distillate stream to an upper portion of said fractional distillation zone as reflux only when the rate at which said fluid distillate stream is withdrawn from an upper portion of said fractional distillation zone is greater than or substantially equal to the rate at which said cooled fluid distillate stream is withdrawn from said cooling zone, and passing the thus withdrawn cooled fluid distillate stream back to said pumping zone when the rate at which said fluid distillate stream is withdrawn from an upper portion of said fractional distillation zone is substantially less than the rate at which said cooled fluid distillate stream is withdrawn from said cooling zone.