Patent ID: 9296667
Filing Date: 2016-03-29
CPC Classification: B01D,C07C

Claim Text:
1. A process for recovering 1,3-butadiene from a C 4 fraction, comprising: feeding a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C contacting the hydrocarbon fraction with a solvent in the extractive distillation system to selectively dissolve a portion of the hydrocarbon fraction; recovering a vapor fraction comprising a first portion of the butanes and the butenes from the extractive distillation system; recovering an enriched solvent fraction comprising the 1,3-butadiene, the 1,2-butadiene, C feeding the enriched solvent fraction to a rectifier to at least partially degas the enriched solvent; recovering a second portion of the butanes and butenes from the rectifier as an overheads fraction; recovering the C recovering a partially degassed solvent comprising 1,2-butadiene and C feeding at least a portion of the partially degassed solvent to a degasser to further degas the solvent; recovering an overheads fraction comprising at least one of C recovering a side draw fraction comprising the C recovering a bottoms fraction comprising degassed solvent from the degasser; compressing the degasser overheads fraction using a liquid ring compressor; and recycling at least a portion of the compressed degasser overheads fraction to the rectifier.