发明授权
US06526777B1 LNG production in cryogenic natural gas processing plants 失效
低温天然气加工厂的液化天然气生产

LNG production in cryogenic natural gas processing plants
摘要:
A process for liquefying natural gas in conjunction with processing natural gas to recover natural gas liquids (NGL) is disclosed. In the process, the natural gas stream to be liquefied is taken from one of the streams in the NGL recovery plant and cooled under pressure to condense it. A distillation stream is withdrawn from the NGL recovery plant to provide some of the cooling required to condense the natural gas stream. The condensed natural gas stream is expanded to an intermediate pressure and supplied to a mid-column feed point on a distillation column. The bottom product from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas, and is routed to the NGL recovery plant so that these heavier hydrocarbons can be recovered in the NGL product. The overhead vapor from the distillation column is cooled and condensed, and a portion of the condensed stream is supplied to a top feed point on the distillation column to serve as reflux. A second portion of the condensed stream is expanded to low pressure to form the liquefied natural gas stream.
信息查询
0/0