US 5,667,643 AGranted

Heat exchanger and double distillation column

AssigneeThe BOC Group, Inc.

InventorsDonald Prentice Satchell, Jr., Venkat Natarajan, Richard Henry Clarke

Life of this patent

Estimating the term…

Loading patent…

Abstract

A heat exchanger is provided which is suitable for use as a condenser/reboiler in a double distillation column. The heat exchanger has alternating first and second passages and a reservoir located above the first and second passages for receiving a first fluid and for containing a froth. A series of orifices can be provided by a distributor tray to provide flow communication between the reservoir and the first passages to allow at least a liquid phase of the froth to weep into the first passages and to be partly vaporized through indirect heat exchange with a second fluid flowing through the second passages. The partial vaporization produces a vapor phase of the froth which can at least in part escape from the orifices and interact with the first fluid to thereby form the froth. A remaining part of the liquid phase, not vaporized through the indirect heat exchange, is discharged from the bottom of the first passages into a sump. The weeping inlet of the liquid phase into the first passages allows for the automatic replenishment of the first passages due to flow mal-distribution.

Claims16

Dependent claims

A heat exchanger for indirectly exchanging heat between first and second fluids and for use with a sump, said heat exchanger comprising:

a plurality of first passages for receiving at least a liquid phase of a froth of a first fluid;
a plurality of second passages for receiving a second fluid;
said first and second passages alternating with one an other in a heat transfer relationship to allow said liquid phase of said froth to partially vaporize and thereby to form a vapor phase of said froth through indirect heat exchange with said second fluid;
said first passages being open at a bottom region of said heat exchanger to discharge at least a liquid resulting from a remaining part of said liquid phase, not vaporized through said indirect heat exchange, to said sump;
inlet and outlet means for introducing and discharging said second fluid to and from said second passages;
a reservoir located above said first and second passages for receiving said first fluid and for containing said froth;
and
orifice means for providing flow communication between said reservoir and said first passage so that at least part of said vapor phase of said froth flows through said orifices to said reservoir and interacts with said first fluid to form said froth;
each of said orifices having a weep point at which said at least said liquid phase of said froth weeps into said second passages through said orifices, thereby to automatically replenish said first passages with said liquid phase of said froth.

6 more elements

A double distillation column for rectifying a mixture containing higher and lower boiling components, said double distillation column comprising:

a higher pressure column and a lower pressure column;
a sump to collect a columns bottom liquid enriched in said higher boiling components;
said higher pressure column having a tower overhead region for collecting a vapor tower overhead enriched in said lower boiling components;
and
at least one condenser/reboiler located within said bottom region of said lower pressure distillation column to condense said vapor tower overhead against vaporizing a reboiler feed, said at least one condenser/reboiler comprising:
a plurality of first passages for receiving at least a liquid phase of a froth composed of said reboiler feed;
a plurality of second passages for receiving said vapor tower overhead;
said first and second passages alternating with one an other in a heat transfer relationship to allow said liquid phase to partially vaporize and thereby to form a vapor phase of said froth through indirect heat exchange with vapor tower overhead;
said first passages being open at a bottom region of said heat exchanger to discharge at least said liquid column bottoms, composed of a remaining part of said liquid phase not vaporized through said indirect heat exchange, to said sump;
inlet and outlet means for introducing said vapor tower overhead into said second passages and for discharging condensed vapor tower overhead from said second passages, respectively;
a reservoir located above said first and second passages for receiving said reboiler feed and for containing said froth;
and
orifice means having orifices for providing flow communication between said reservoir and said first passages so that at least part of said vapor phase of said froth flows through said orifices to said reservoir and interacts with said reboiler feed to form said froth;
each of said orifices having a weep point at which said at least said liquid phase of said froth weeps into said first passages through said orifices, thereby to automatically replenish said first passages with said liquid phase of said froth.

11 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/573,737Filed 18 Dec 1995
Granted: 16 Sep 1997
Term ends: Not estimatedThe source records don’t support an estimate.

Classification10 codes

F25J 5/002
Arrangements of cold exchangers or cold accumulators in separation or liquefaction plants: for continuously recuperating cold, i.e. in a so-called…
F25J 3/04412
Using a dual pressure main column system: in a classical double column flowsheet, i.e. with thermal coupling by a main reboiler-condenser in the…
F25J 3/04793
Operation, control and regulation of the process; Instrumentation within the process: rectification, e.g. columns; Reboiler-condenser
F25J 5/005
For continuously recuperating cold, i.e. in a so-called recuperative heat exchanger: in a reboiler-condenser, e.g. within a column