US 11,725,879 B2
Methods and configuration for retrofitting NGL plant for high ethane recovery
John Mak, Santa Ana, CA (US); Sabrina Devone, Richmond, TX (US); James Shih, Houston, TX (US); and Curt Graham, Mission Viejo, CA (US)
Assigned to Fluor Technologies Corporation, Irving, TX (US)
Appl. No. 16/325,696
Filed by Fluor Technologies Corporation, Sugar Land, TX (US)
PCT Filed Sep. 8, 2017, PCT No. PCT/US2017/050636
§ 371(c)(1), (2) Date Feb. 14, 2019,
PCT Pub. No. WO2018/049128, PCT Pub. Date Mar. 15, 2018.
Claims priority of provisional application 62/489,234, filed on Apr. 24, 2017.
Claims priority of provisional application 62/385,748, filed on Sep. 9, 2016.
Prior Publication US 2020/0141639 A1, May 7, 2020
Int. Cl. F25J 3/02 (2006.01); C10G 5/04 (2006.01); C10G 5/06 (2006.01)
CPC F25J 3/0238 (2013.01) [C10G 5/04 (2013.01); C10G 5/06 (2013.01); F25J 3/0209 (2013.01); F25J 3/0233 (2013.01); C10G 2300/1025 (2013.01); C10G 2300/4056 (2013.01); F25J 2200/02 (2013.01); F25J 2200/30 (2013.01); F25J 2200/76 (2013.01); F25J 2205/04 (2013.01); F25J 2205/60 (2013.01); F25J 2215/62 (2013.01); F25J 2290/80 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A natural gas liquid plant bolt-on unit, comprising:
an absorber configured to condense an ethane content from an overhead gas stream from a demethanizer using a cold lean residue gas to produce a liquid portion and a vapor portion, wherein the demethanizer is configured to receive the liquid portion as a first reflux;
a reflux exchanger configured to receive at least a portion of the vapor portion and use the portion of the vapor portion to provide cooling within the reflux exchanger; and
a flow control valve configured to direct between about 70% to 90% of the vapor portion to a subcool exchanger to provide cooling to a portion of a feed stream that is directed to the demethanizer and configured to direct about 10% to about 30% of the vapor portion to the reflux exchanger to provide the cooling within the reflux exchanger to cool a residue gas stream that is directed to the absorber.