US 2013/0055757 A1 · METHOD AND SYSTEM TO PREVENT CARRY-OVER OF HYDROCARBON MIST FROM AN NGL COLUMN OF AN LNG PLANT

Abstract

The present disclosure is directed to a method and system for preventing carry-over of C2+ hydrocarbon mist from an NGL recovery column in an LNG plant. A wash loop of recirculating liquid hydrocarbon is provided at the upper portion of the NGL column. A sidestream of liquid hydrocarbons collected within the column is removed from the column and pumped to sufficient height to be returned to the column at a temperature substantially equivalent to the temperature of liquid with the upper portion of the column. In one embodiment, liquid hydrocarbons of a desired composition can be loaded and reloaded to a working medium holding drum in fluid communication with the top of the column. The working medium can be selected to be sufficiently heavy not to be lost from the column and to have a suitable freezing point to avoid freezing within the column.

Claims15

Dependent claims

A method for reducing hydrocarbon mist from escaping the top of an NGL recovery column in an LNG plant, the method comprising:

a. flowing a hydrocarbon gas stream including a hydrocarbon mist upwardly in an NGL column;
b. spraying droplets of a hydrocarbon liquid into the gas stream to strip at least some of the hydrocarbon mist from the upwardly flowing gas stream;
c. collecting the droplets of the hydrocarbon liquid in a tray within the column;
d. removing a liquid sidestream of the collected hydrocarbon liquid from the column;
and
e. returning at least a portion of the liquid sidestream to form the droplets which are sprayed in step b.

3 more elements

A system for preventing hydrocarbon mist from escaping the top of an NGL recovery column in an LNG plant, comprising:

a. a column for recovering NGL, the column comprising:
i. a natural gas inlet for feeding natural gas to the column;
ii. an NGL outlet at a lower portion of the column for dispensing natural gas liquids from the column;
iii. a gas outlet at an upper portion of the column for removing gaseous components from the column;
iv. at least one tray for collecting liquids within the column;
v. a spray mechanism for generating a spray of droplets which are collected as liquids in the at least one tray;
vi. a liquid inlet for receiving and feeding liquid to the spray mechanism;
vii. a liquid outlet for receiving liquid from the at least one tray;
and
b. a loop for fluidly connecting the liquid outlet with the liquid inlet to transport a sidestream of liquid, the loop including a pump in fluid communication with the liquid outlet for receiving and pumping the at least a portion of the sidestream to the liquid inlet.

7 more elements

Dependencies are inferred from the claim text.

Method and system to prevent carry-over of hydrocarbon mist from an ngl column of an lng plant

Life of this patent

Method and system to prevent carry-over of hydrocarbon mist from an ngl column of an lng plant

Life of this patent

Abstract

Claims15