| 摘要 |
PCT No. PCT/EP97/01000 Sec. 371 Date Aug. 5, 1998 Sec. 102(e) Date Aug. 5, 1998 PCT Filed Feb. 27, 1997 PCT Pub. No. WO97/32172 PCT Pub. Date Sep. 4, 1997Method of reducing the amount of components having low boiling points in liquefied natural gas comprising passing the liquefied natural gas at liquefaction pressure through the hot side of an external heat exchanger to obtain cooled liquefied natural gas, allowing the cooled liquefied natural gas to expand dynamically to an intermediate pressure and statically to a low pressure to obtain expanded fluid, and introducing expanded fluid into the upper part of a fractionation column provided with a contacting section arranged between the upper part and the lower part of the fractionation column; passing a direct side stream at low pressure through the cold side of the external heat exchanger to obtain heated two-phase fluid; introducing the heated two-phase fluid into the lower part of the fractionation column and allowing the vapor to flow upwards through the contacting section; allowing the liquid of the expanded fluid to flow downwards through the contacting section; and withdrawing from the lower part of the fractionation column a liquid product stream having a reduced content of components having low boiling points, and from the upper part of the fractionation column a gas stream which is enriched in components having low boiling points. |
