发明名称 |
Dual column process to remove nitrogen from natural gas |
摘要 |
Nitrogen is removed from a natural gas feed stream by a cryogenic distillation process in which said feed stream is fed to a primary column of a distillation column system having a primary column and a secondary column fed from and operating at substantially the same pressure as the primary column. At least a portion of a primary column methane-rich bottoms liquid is expanded and at least partially vaporized in heat exchange with a condensing primary column nitrogen-enriched vapor. The at least partially condensed primary column nitrogen-enriched vapor is returned to the primary column to provide higher temperature reflux to the distillation column system. A secondary column methane-rich bottoms liquid is at least partially vaporized in heat exchange with a condensing nitrogen-rich overhead vapor to produce a further methane-rich product. At least a portion of the at least partially condensed nitrogen-rich overhead vapor portion is returned to the primary or secondary column to provide lower temperature reflux to the distillation column system.
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申请公布号 |
US5617741(A) |
申请公布日期 |
1997.04.08 |
申请号 |
US19960597414 |
申请日期 |
1996.02.08 |
申请人 |
AIR PRODUCTS AND CHEMICALS, INC. |
发明人 |
MCNEIL, BRIAN A.;EVANS, MICHAEL H. |
分类号 |
F25J3/02;(IPC1-7):F25J3/02;F25J3/08 |
主分类号 |
F25J3/02 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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