US 12,404,222 B2
Systems and methods for enhancing the extractive section operability and modifying solvent heat recovery cycle in the separation of C4 mixtures
Ahmad Mahdi Alshehri, Riyadh (SA); Mohammed Sabri Abdelghani, Riyadh (SA); and Ahmed Alzenaidi, Riyadh (SA)
Assigned to SABIC Global Technologies B.V., Bergen op Zoom (NL)
Appl. No. 17/760,103
Filed by SABIC Global Technologies B.V., Bergen op Zoom (NL)
PCT Filed Jan. 26, 2021, PCT No. PCT/IB2021/050591
§ 371(c)(1), (2) Date Aug. 4, 2022,
PCT Pub. No. WO2021/156707, PCT Pub. Date Aug. 12, 2021.
Claims priority of provisional application 62/971,163, filed on Feb. 6, 2020.
Prior Publication US 2023/0064093 A1, Mar. 2, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. B01D 3/40 (2006.01); B01D 3/14 (2006.01); B01D 3/32 (2006.01); C07C 7/00 (2006.01); C07C 7/08 (2006.01); C07C 9/10 (2006.01); C07C 11/08 (2006.01); C07C 11/167 (2006.01); C07C 11/22 (2006.01); C07C 11/24 (2006.01)
CPC C07C 7/08 (2013.01) [B01D 3/143 (2013.01); B01D 3/322 (2013.01); B01D 3/40 (2013.01); C07C 7/005 (2013.01); C07C 9/10 (2013.01); C07C 11/08 (2013.01); C07C 11/167 (2013.01); C07C 11/22 (2013.01); C07C 11/24 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method of separating a mixture of C4 hydrocarbons and a solvent, the method comprising:
separating the mixture of C4 hydrocarbons and the solvent in a rectifier column to produce a top stream comprising at least some C4 hydrocarbons and a bottom stream comprising (a) primarily the solvent and (b) some C4 hydrocarbons;
separating the bottom stream in a degasser column to produce a lean solvent stream comprising primarily the solvent;
wherein a reboiler for the rectifier column comprises four or more heat exchangers in series, wherein at least three of the heat exchangers are operated using the lean solvent stream as a heating medium, and wherein a last heat exchanger of the four or more heat exchangers in series is operated using low pressure steam as a heating medium;
wherein the degasser column is operated at an overhead boiling temperature range of 85 to 100° C.; and
wherein the method further comprises steps of:
flowing the lean solvent stream to at least one of the four or more heat exchangers as a heating medium for the reboiler to heat a rectifier feed stream to produce a first cooled lean solvent stream and a heated rectifier feed stream; and
flowing the low pressure steam to the last heat exchanger of the four or more heat exchangers as a heating medium to heat the reboiler to heat the heated rectifier feed stream and produce a further heated rectifier feed stream.