Integrated NGL Recovery In the Production Of Liquefied Natural Gas
First Claim
1. A process for the liquefaction of natural gas and the recovery of components heavier than methane from the natural gas, wherein the process comprises:
- (a) introducing a natural gas feed into a first distillation column and separating in the first distillation column the natural gas feed into an overhead vapor enriched in methane and a bottoms liquid enriched in components heavier than methane;
(b) withdrawing from the first distillation column a first overhead vapor stream enriched in methane and a bottoms liquid stream enriched in components heavier than methane;
(c) cooling the first overhead vapor stream enriched in methane to provide a cooled overhead stream enriched in methane, combining the cooled overhead stream enriched in methane with a liquified natural gas reflux stream to provide a two-phase mixture, and separating the two-phase mixture to provide a liquid reflux stream and a second overhead vapor stream enriched in methane;
(d) introducing the liquid reflux stream into the first distillation column to provide reflux to the distillation column;
(e) introducing the second overhead vapor stream enriched in methane into a main heat exchanger comprising only two tube bundles, said bundles consisting of a warm bundle and a cold bundle, and cooling and liquifying the second overhead vapor stream in the warm bundle to provide a single-phase, liquefied natural gas product; and
(f) subcooling at least a portion of the liquified natural gas product in the cold bundle of the main heat exchanger to provide a subcooled liquified natural gas product, and withdrawing the subcooled liquified natural gas product from the main heat exchanger.
1 Assignment
0 Petitions
Accused Products
Abstract
Process for the liquefaction of natural gas and the recovery of components heavier than methane where natural gas is cooled and separated in a first distillation column into an overhead vapor enriched in methane and a bottoms stream enriched in components heavier than methane, where the first distillation column utilizes a liquefied methane-containing reflux stream. This reflux stream may be provided by a condensed portion of the overhead vapor or a portion of totally condensed overhead vapor that is subsequently warmed. The bottoms stream may be separated in one or more additional distillation columns to provide one or more product streams, any of which are partially or totally withdrawn as recovered hydrocarbons. A stream of unrecovered liquid hydrocarbons may be combined with either the condensed portion of the overhead vapor or a portion of totally condensed overhead vapor that is subsequently warmed.
26 Citations
26 Claims
-
1. A process for the liquefaction of natural gas and the recovery of components heavier than methane from the natural gas, wherein the process comprises:
-
(a) introducing a natural gas feed into a first distillation column and separating in the first distillation column the natural gas feed into an overhead vapor enriched in methane and a bottoms liquid enriched in components heavier than methane; (b) withdrawing from the first distillation column a first overhead vapor stream enriched in methane and a bottoms liquid stream enriched in components heavier than methane; (c) cooling the first overhead vapor stream enriched in methane to provide a cooled overhead stream enriched in methane, combining the cooled overhead stream enriched in methane with a liquified natural gas reflux stream to provide a two-phase mixture, and separating the two-phase mixture to provide a liquid reflux stream and a second overhead vapor stream enriched in methane; (d) introducing the liquid reflux stream into the first distillation column to provide reflux to the distillation column; (e) introducing the second overhead vapor stream enriched in methane into a main heat exchanger comprising only two tube bundles, said bundles consisting of a warm bundle and a cold bundle, and cooling and liquifying the second overhead vapor stream in the warm bundle to provide a single-phase, liquefied natural gas product; and (f) subcooling at least a portion of the liquified natural gas product in the cold bundle of the main heat exchanger to provide a subcooled liquified natural gas product, and withdrawing the subcooled liquified natural gas product from the main heat exchanger. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 26)
-
-
19. An apparatus for the liquefaction of natural gas and the recovery of components heavier than methane from the natural gas, wherein the apparatus comprises:
-
(a) a first distillation column adapated to separate a natural gas feed into an overhead vapor enriched in methane and a bottoms liquid enriched in components heavier than methane and thereby provide a first overhead vapor stream enriched in methane and a bottoms liquid stream enriched in components heavier than methane; (b) a cooling system adapted to cool the first overhead vapor stream enriched in methane to provide a cooled overhead stream enriched in methane; (c) a reflux drum adapted to receive a two-phase mixture, formed from the combination of the cooled overhead stream enriched in methane and a liquified natural gas reflux stream, and adapted to separate the two-phase mixture to provide a liquid reflux stream and a second overhead vapor stream enriched in methane; (d) piping adapted to introduce the cooled overhead stream and the liquified natural gas reflux stream, as separate streams or as a combined stream, into the reflux drum; (e) piping adapted to introduce the liquid reflux stream into the first distillation column to provide reflux to the distillation column; (f) a main heat exchanger comprising only two tube bundles, said bundles consisting of a warm bundle and a cold bundle, the warm bundle being adapted to cool and liquify the second overhead vapor stream to provide a single-phase, liquified natural gas product, and the cold bundle being adapted to subcool at least a portion of the liquified natural gas product to provide a subcooled liquified natural gas product; (g) piping adapted to introduce the second overhead vapor stream into the warm bundle of the main heat exchanger; and (h) piping adapted to withdraw the liquified natural gas product stream from the cold bundle of the main heat exchanger. - View Dependent Claims (20, 21, 22, 23, 24, 25)
-
Specification