Verfahren und Vorrichtung zur Abtrennung von Kohlendioxyd von Kohlenwasserstoffen

摘要

1286682 Separation of gas mixtures FLUOR CORP and AMOCO PRODUCTION CO 5 Dec 1969 [5 Dec 1968] 59639/69 Heading F4P In a process for obtaining liquid ethane and higher hydrocarbon products free of carbon dioxide and methane, the undesirable gases are removed in one step and without the separation of solid carbon dioxide. Compressed feed gas is partially condensed by heat exchange at 2 and passed into a separator 4; liquid phase is passed directly to a mid-point 11 of a separating column 9 and the gaseous phase is expanded through a turbine 7 before being passed to the top 9a of the column 9. The pressure and temperature of the column prevents separation of solid CO 2 , and CO 2 and methane gas are removed in line 13 and used to cool the feed stream. A portion of the condensate in column 9 is used in re-boiler 12, whilst the remainder is passed via pump 18 to a second separating column 20. Ethane/propane gas is removed as overhead from column 20, condensed by heat exchange in reboiler 12, and passed via accumulator 28 and pump 30 either to product store or to reflux in column 20. Butane and higher fractions are removed as bottom liquid from column 20. The turbine 7 also drives a compressor 16 for the methane and carbon dioxide gas in line 13, and may drive a compressor 16a for the feed gas.