| 摘要 |
In the liquefaction of a hydrocarbon by indirect heat exchange with the refrigerant mixture of a refrigerant mixture cycle, the refrigerant mixture being compressed in multiple stages, the compressed refrigerant mixture (23) is at least partially condensed (E4) downstream of the penultimate compressor stage and is fractionated (D4) into a higher-boiling liquid fraction (26) and a lower-boiling gas fraction (24). The lower-boiling gas fraction (24) is compressed to the final pressure, partially condensed (E5) and fractionated (D5) into a lower-boiling gas fraction (10) and a higher-boiling liquid fraction (27). The higher-boiling liquid fraction (27) is added to the partially condensed refrigerant mixture stream (23), and the gas fraction (10) forms the lower-boiling refrigerant mixture fraction and the liquid fraction (26) forms the higher boiling refrigerant mixture fraction of the refrigerant mixture cycle. Alternatively, the compressed refrigerant mixture (20, 31, 34) can be partially condensed (E3, E4, E5) after each compressor stage and fractionated in each case into a lower-boiling gas fraction (21, 32, 10) and a higher-boiling liquid fraction (30, 33, 35). Only the gas fraction (21, 32) from the partial condensation (E3, E4) in each case is further compressed and the liquid fractions (33, 35) from the second fractionation (D4, D5) are added to the partially condensed stream (20) from the first compressor stage upstream of its fractionation (D3). The gas fraction (10) from the final fractionation (D5) forms the lower-boiling refrigerant mixture fraction and the liquid fraction (30) from the first fractionation (D3) forms the higher-boiling refrigerant mixture fraction of the refrigerant mixture cycle. |
