| 摘要 |
An improvement in the separation of a multi-component mixture, especially a well head stream, into gaseous and liquid phases by multi-component flash separation at reducing pressures, comprises recycling at least a part of the gaseous fraction recovered from a stage after the first stage to a preceding stage, and preferably the immediately preceding stage, to mix with the liquid phase which is separated in said preceding stage and at substantially the pressure of said preceding stage. This (a) increases the gas/liquid ratio in each stage, the amount of liquid recovered from the last stage and the proportion of medium-boiling components therein; (b) results in more gas being available from the higher pressure stages and (c) yields gases having narrower boiling ranges. Three separation stages are preferred and pipeline gas, crude LPG and a local fuel gas to supply the energy requirements of the separation can be derived from the gaseous fractions recovered from the separation stages. |
