发明名称 |
Nitrogen rejection method and apparatus |
摘要 |
Nitrogen is rejected from a feed natural gas stream comprising methane and nitrogen so as to form a primary methane product. The mole fraction of nitrogen in the feed natural gas increases over a period of time. The feed natural gas stream is cooled in a main heat exchanger and is rectified in a double rectification column. A primary product methane stream and a secondary nitrogen-enriched product stream are withdrawn from the rectification column. The secondary nitrogen-enriched product stream has a mole fraction of methane at or above a chosen minimum value when the said mole fraction of nitrogen is at a minimum. When the said mole fraction of nitrogen rises to a value at which the mole fraction of methane in the secondary nitrogen-enriched product stream falls below the chosen minimum, a part of the feed gas is introduced through conduit into the secondary nitrogen-enriched product stream so as to restore its mole fraction of methane to the chosen minimum value or a value thereabove.
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申请公布号 |
US2004182109(A1) |
申请公布日期 |
2004.09.23 |
申请号 |
US20030701702 |
申请日期 |
2003.11.05 |
申请人 |
OAKEY JOHN DOUGLAS;DAVIES BRIAN MORICE |
发明人 |
OAKEY JOHN DOUGLAS;DAVIES BRIAN MORICE |
分类号 |
F25J3/02;(IPC1-7):F25J3/00 |
主分类号 |
F25J3/02 |
代理机构 |
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