Back to results
US 6,631,626 B1Granted
Natural gas liquefaction with improved nitrogen removal
AssigneeConocoPhillips Company
InventorPaul R. Hahn
Life of this patent
Estimating the term…
Abstract
Natural gas liquefaction system employing a zeolite adsorbent for removing nitrogen from pretreated natural gas.
Claims62
In a process for liquefying natural gas, the improvement comprising:
- (a) removing nitrogen from the natural gas using a molecular sieve having a pore size in the range of from about 3.5 to about 4.0 angstroms;
- (b) using at least a portion of the natural gas as a refrigerant in a methane economizer;
- and
- (c) downstream of the molecular sieve, compressing at least a portion of the natural gas used as a refrigerant.
1 more element
A natural gas liquefaction process comprising the steps of:
- (a) adsorbing nitrogen from the natural gas, thereby providing a low-nitrogen natural gas stream;
- (b) cooling at least a portion of the low-nitrogen natural gas stream in a propane chiller, thereby providing a first-stage chilled natural gas stream;
- (c) cooling at least a portion of the first-stage chilled natural gas stream in an ethylene chiller, thereby providing a second-stage chilled natural gas stream;
- and
- (d) using at least a portion of the second-stage chilled natural gas stream as a refrigerant in an open methane cycle.
2 more elements
A natural gas liquefaction process comprising the steps of:
- (a) cooling the natural gas in a propane chiller, thereby providing a first-stage chilled natural gas stream;
- (b) cooling at least a portion of the first-stage chilled natural gas stream in an ethylene chiller, thereby providing a second-stage chilled natural gas stream;
- (c) cooling at least a portion of the second-stage chilled natural gas stream in a methane economizer, thereby providing a third-stage chilled natural gas stream;
- (d) using at least a portion of the third-stage chilled natural gas stream as a refrigerant in the methane economizer;
- and
- (e) adsorbing nitrogen from at least a portion of the natural gas used as a refrigerant in the methane economizer, thereby providing a low-nitrogen natural gas stream.
3 more elements
An apparatus for liquefying natural gas, said apparatus comprising:
- a pretreatment system operable to remove at least one contaminant from the natural gas, said at least one contaminant being selected from the group consisting of an acid gas, water, mercury, and combinations thereof;
- a nitrogen removal system disposed downstream of the pretreatment system and operable to remove nitrogen from the pretreated natural gas, said natural gas removal system including a molecular sieve having a pore size in the range of from about 3.5 to about 4.0 angstroms;
- a propane chiller disposed downstream of the pretreatment system and operable to cool the natural gas;
- an ethylene chiller disposed downstream of the propane chiller and operable to cool the natural gas;
- and
- a methane cycle system disposed downstream of the ethylene chiller.
3 more elements
A process for liquefying natural gas, said process comprising the steps of:
- (a) removing nitrogen from the natural gas using a molecular sieve having a pore size in the range of from about 3.5 to about 4.0 angstroms;
- (b) cooling the natural gas in a first chiller;
- and
- (c) cooling the natural gas in a second chiller.
1 more element
Dependencies are inferred from the claim text.