US 12,135,166 B2
Process for separating hydrogen from an olefin hydrocarbon effluent vapor stream
James Zhao, Houston, TX (US); and Shukui Zhao, Katy, TX (US)
Assigned to Enflex, Inc., Houston, TX (US)
Filed by EnFlex, Inc., Houston, TX (US)
Filed on May 31, 2023, as Appl. No. 18/204,005.
Application 18/204,005 is a division of application No. 17/191,427, filed on Mar. 3, 2021, granted, now 11,668,523.
Application 17/113,640 is a division of application No. 15/988,601, filed on May 24, 2018, granted, now 10,859,313, issued on Dec. 8, 2020.
Application 17/191,427 is a continuation of application No. 17/191,373, filed on Mar. 3, 2021, granted, now 11,674,748.
Application 17/191,373 is a continuation in part of application No. 17/113,640, filed on Dec. 7, 2020, granted, now 11,448,460, issued on Sep. 20, 2022.
Application 15/988,601 is a continuation in part of application No. 15/600,758, filed on May 21, 2017, granted, now 10,633,305, issued on Apr. 28, 2020.
Prior Publication US 2023/0304732 A1, Sep. 28, 2023
Int. Cl. F25J 3/00 (2006.01); F25J 3/02 (2006.01); F25J 3/06 (2006.01)
CPC F25J 3/0252 (2013.01) [F25J 3/0219 (2013.01); F25J 3/062 (2013.01); F25J 3/0645 (2013.01); F25J 3/0655 (2013.01); F25J 2200/02 (2013.01); F25J 2205/04 (2013.01); F25J 2210/04 (2013.01); F25J 2210/12 (2013.01); F25J 2210/62 (2013.01); F25J 2215/02 (2013.01); F25J 2215/04 (2013.01); F25J 2215/10 (2013.01); F25J 2215/64 (2013.01); F25J 2230/08 (2013.01); F25J 2230/20 (2013.01); F25J 2230/30 (2013.01); F25J 2230/32 (2013.01); F25J 2230/60 (2013.01); F25J 2235/60 (2013.01); F25J 2240/04 (2013.01); F25J 2240/40 (2013.01); F25J 2245/02 (2013.01); F25J 2270/06 (2013.01); F25J 2270/904 (2013.01)] 1 Claim
OG exemplary drawing
 
1. A process for providing refrigeration to streams within an integrated main heat exchanger comprising:
a. providing a pressurized and totally condensed liquid refrigerant stream, wherein the pressurized and totally condensed liquid refrigerant stream comprises a pressure between 1,000 kPa·G and 1,750 kPa·G;
b. sub-cooling the pressurized and totally condensed liquid refrigerant stream in the integrated main heat exchanger to provide sub-cooled liquid stream, wherein the sub-cooled liquid stream comprises a pressure between 15 kPa·G and 50 kPa·G and a temperature between 10° C. and −25° C.;
c. lowering the pressure of the sub-cooled liquid stream in a first control valve to provide a first pressure-reduced, temperature-decreased vapor/liquid mixed stream, wherein the first pressure-reduced, temperature-decreased vapor/liquid mixed stream comprises a temperature between −30° C. and −45° C.;
d. introducing the first pressure-reduced, temperature-decreased vapor/liquid mixed stream into a first thermosiphon vessel to provide a first cold liquid refrigerant stream and a first flashed vapor stream;
e. circulating the first cold liquid refrigerant stream from a bottom outlet of the first thermosiphon vessel, through the integrated main heat exchanger, and then back to an upper inlet of the first thermosiphon vessel to maintain a steady internal liquid level within the first thermosiphon vessel, wherein the integrated main heat exchanger vaporizes the first cold liquid refrigerant stream to provide a first two-phase refrigerant stream, wherein the first two-phase refrigerant stream comprises between 30% and 50% vapor;
f. compressing the first flashed vapor stream in at least one first compressor to provide a first compressed stream;
g. cooling the first compressed stream in a final stage discharge condenser to provide the pressurized and totally condensed liquid refrigerant stream;
h. providing a pressurized and cooled refrigerant stream, wherein the pressurized and cooled refrigerant stream comprises a pressure between 1,650 kPa·G and 1,950 kPa·G;
i. cooling the pressurized and cooled refrigerant stream in the integrated main heat exchanger to provide a cooled and totally condensed liquid stream, wherein the cooled and totally condensed liquid stream comprises a temperature between −30° C. and −40° C.;
j. lowering the pressure and temperature of the cooled and totally condensed liquid stream in a second control valve to provide a second pressure-reduced temperature-decreased vapor/liquid mixed stream, wherein the second pressure-reduced temperature-decreased vapor/liquid mixed stream comprises a pressure between 450 kPa·G and 700 kPa·G and a temperature between −50° C. and −70° C.;
k. introducing the second pressure-reduced temperature-decreased vapor/liquid mixed stream into a second thermosiphon vessel to provide a first warm liquid refrigerant stream and a second flashed vapor stream;
l. circulating the first warm liquid refrigerant stream from a bottom outlet of the second thermosiphon vessel, through the integrated main heat exchanger, and then back to an upper inlet of the second thermosiphon vessel to maintain a steady internal liquid level within the second thermosiphon vessel, wherein the integrated main heat exchanger vaporizes the first warm liquid refrigerant stream to provide a second two-phase refrigerant stream, wherein the second two-phase refrigerant stream comprises between 30% and 50% vapor;
m. drawing a second warm liquid refrigerant stream from the first warm liquid refrigerant stream and lowering the pressure of the second warm liquid refrigerant stream in a third control valve to provide a pressure-reduced temperature-decreased liquid stream, wherein the pressure-reduced temperature-decreased liquid stream comprises a pressure between 5 kPa·G and 50 kPa·G and a temperature between −95° C. and −115° C.;
n. introducing the pressure-reduced temperature-decreased liquid stream to a third thermosiphon vessel to provide a second cold liquid refrigerant stream and a third flashed vapor stream;
o. circulating the second cold liquid refrigerant stream from a bottom outlet of the third thermosiphon vessel, through the integrated main heat exchanger, and then back to an upper inlet of the third thermosiphon vessel to maintain a steady internal liquid level within the third thermosiphon vessel, wherein the integrated main heat exchanger vaporizes the second cold liquid refrigerant stream to provide a third two-phase refrigerant stream, wherein the third two-phase refrigerant stream may comprise between 30% and 50% vapor;
p. compressing the third flash vapor stream in a second compressor to provide a first stage recycle compression discharge stream;
q. combining the second flashed vapor stream and the first stage recycle compression discharge stream to provide a combined feed stream;
r. compressing the combined feed stream in a third compressor to provide a second compressed; and
s. cooling the second compressed stream in a final stage discharger cooler to provide the first pressurized and cooled refrigerant stream.