| 摘要 |
Substantially all the nitrogen is removed from natural gas during the production of LNG, without producing mixed nitrogen/methane streams needing recycle and further processing, or requiring compression for burning as fuel, by operating both the high pressure and the low pressure multistage distillation towers of a two column cryogenic nitrogen rejection unit to produce acceptable liquefied natural gas as tower bottom products, while the low pressure tower is further operated to produce as an overhead a gas steam containing no more than about 1% methane for safe venting to the atmosphere. |
