METHODS AND APPARATUSES FOR REFORMING OF HYDROCARBONS INCLUDING RECOVERY OF PRODUCTS USING A RECONTACTING ZONE

• US 20160115096A1
• Filed: 10/27/2014
• Published: 04/28/2016
• Est. Priority Date: 10/27/2014
• Status: Active Grant

• Current Assignee: UOP Llc (Honeywell International Inc.)
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: Tsai, Robert Edison, Zhu, Xin X., Ngo, Tokhanh, Yanez, William, Lane, Lisa
• Granted Patent: US 9,637,426 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01D 2256/16 Hydrogen
• CPC Class Codes: B01D 2256/24 Hydrocarbons
• CPC Class Codes: B01D 2257/7022 Aliphatic hydrocarbons
• CPC Class Codes: B01D 53/002 by condensation
• CPC Class Codes: C01B 2203/0233 the reforming step being a steam reforming step
• CPC Class Codes: C01B 2203/048 the impurity being an organic compound
• CPC Class Codes: C01B 2203/0495 the impurity being water
• CPC Class Codes: C01B 2203/0872 Methods of cooling
• CPC Class Codes: C01B 2203/1235 Hydrocarbons
• CPC Class Codes: C01B 2203/1247 Higher hydrocarbons
• CPC Class Codes: C01B 3/52 by contacting with liquids; Regeneration of used liquids C01B3/508 takes precedence
• CPC Class Codes: C07C 7/005 Processes comprising at least two steps in series

Abstract

Embodiments of apparatuses and methods for reforming of hydrocarbons including recovery of products are provided. In one example, a method comprises separating a reforming-zone effluent to form a net gas phase stream and a liquid phase hydrocarbon stream. The net gas phase stream is compressed, partially condensed and cooled to form a partially condensed, compressed net gas phase stream. The partially condensed, compressed net gas phase stream is separated to form an intermediate gas phase stream. The intermediate gas phase stream and the liquid phase hydrocarbon stream are combined to form a two-phase combined stream. The two-phase combined stream is cooled and separated to form an H₂-rich stream and a cooled second intermediate liquid phase hydrocarbon stream that is enriched with C₃/C₄ hydrocarbons and further comprises C₅⁺ hydrocarbons.

Claims

1. An apparatus for reforming of hydrocarbons including recovery of products, the apparatus comprising:

a separation zone configured to receive and separate a reforming-zone effluent that comprises H₂, C₄⁻

hydrocarbons, and C₅⁺ hydrocarbons including aromatics to form a net gas phase stream that comprises H₂ and C₆⁻

hydrocarbons and a liquid phase hydrocarbon stream that comprises C₅⁺ hydrocarbons;

a first compressor configured to receive and compress the net gas phase stream to form a compressed net gas phase stream;

a first cooler configured to receive and partially condense and cool the compressed net gas phase stream to form a partially condensed, compressed net gas phase stream;

a knockout drum configured to receive and separate the partially condensed, compressed net gas phase stream into an intermediate gas phase stream and a first intermediate liquid phase hydrocarbon stream; and

a recontacting zone configured to receive and combine the intermediate gas phase stream and the liquid phase hydrocarbon stream to extract C₃/C₄ hydrocarbons from the intermediate gas phase stream to the liquid phase hydrocarbon stream and to form a two-phase combined stream, wherein the recontacting zone comprises;

a chiller configured to receive and cool the two-phase combined stream to form a cooled two-phase combined stream; and

a recontact drum configured to receive and separate the cooled two-phase combined stream to form an H₂-rich stream and a cooled second intermediate liquid phase hydrocarbon stream that is enriched with C₃/C₄ hydrocarbons and further comprises C₅⁺ hydrocarbons.

2. The apparatus of claim 1, wherein the separation zone is configured to receive the first intermediate liquid phase hydrocarbon stream as a recycle stream for further separation.

3. The apparatus of claim 1, further comprising:

at least one heater, heat exchanger, or combinations thereof configured to receive and heat at least a portion of the cooled second intermediate liquid phase hydrocarbon stream to form a heated second intermediate liquid phase hydrocarbon stream;

a stabilizer configured to receive and separate the heated second intermediate liquid phase hydrocarbon stream to form a C₅⁺ hydrocarbon-rich reformate stream that comprises primarily C₅⁺ hydrocarbons and a stabilizer gas stream that comprises H₂ and C₄⁻

hydrocarbons; and

a stabilizer gas separation zone configured to receive and partially condense and cool at least a portion of the stabilizer gas stream to form a partially condensed stabilizer net gas stream, wherein the stabilizer gas separation zone comprises;

a separator configured to receive and separate the partially condensed stabilizer net gas stream to form a C₃/C₄ hydrocarbon-rich LPG stream that comprises primarily C₃/C₄ hydrocarbons and a light ends gas stream that comprises H₂ and C₂⁻

hydrocarbons.

4. The apparatus of claim 3, wherein the stabilizer gas separation zone comprises at least one heat exchanger, chiller, cooler, or combination thereof configured to receive and partially condense and cool the at least the portion of the stabilizer gas stream to form the partially condensed stabilizer net gas stream.

5. The apparatus of claim 4, wherein the at least one heat exchanger, chiller, cooler, or combination thereof is a stabilizer gas separation zone heat exchanger configured for indirect heat exchange between at least a portion of the cooled second intermediate liquid phase hydrocarbon stream and the at least the portion of the stabilizer gas stream to form a first partially heated, second intermediate liquid phase hydrocarbon stream and the partially condensed stabilizer net gas stream, respectively, wherein the apparatus further comprises a stabilizer heat exchanger that is configured for indirect heat exchange between the first partially heated, second intermediate liquid phase hydrocarbon stream and the C₅⁺ hydrocarbon-rich reformate stream to form the heated second intermediate liquid phase hydrocarbon stream, wherein the at least one heater, heat exchanger, or combinations thereof comprises the stabilizer gas separation zone heat exchanger and the stabilizer heat exchanger.

6. The apparatus of claim 4, wherein the recontacting zone comprises a recontacting zone heat exchanger that is configured for indirect heat exchange between the two-phase combined stream and at least a portion of the cooled second intermediate liquid phase hydrocarbon stream to form a partially cooled two-phase combined stream and a second partially heated, second intermediate liquid phase hydrocarbon stream, wherein the chiller is configured to receive and cool the partially cooled two-phase combined stream to form the cooled two-phase combined stream, wherein the apparatus further comprises a stabilizer heat exchanger that is configured for indirect heat exchange between the second partially heated, second intermediate liquid phase hydrocarbon stream and the C₅⁺ hydrocarbon-rich reformate stream to form the heated second intermediate liquid phase hydrocarbon stream, wherein the at least one heater, heat exchanger, or combinations thereof comprises the recontacting zone heat exchanger and the stabilizer heat exchanger.

7. The apparatus of claim 4, wherein the stabilizer gas separation zone comprises a dryer that is upstream from the at least one heat exchanger, chiller, cooler, or combination thereof and is configured to remove water from the at least the portion of the stabilizer gas stream before the portion of the stabilizer gas stream is introduced to the at least one heat exchanger, chiller, cooler, or combination thereof.

8. The apparatus of claim 1, wherein the recontacting zone comprises a dryer that is upstream from the chiller and is configured to remove water from the intermediate gas phase stream before the intermediate gas phase stream and the liquid phase hydrocarbon stream are combined to form the two-phase combined stream.

9. The apparatus of claim 1, wherein the recontacting zone comprises:

a second compressor configured to receive and compress the intermediate gas phase stream to form a compressed intermediate gas phase stream;

a second cooler configured to receive and partially cool the compressed intermediate gas phase stream to form a partially cooled, compressed intermediate gas phase stream, wherein the recontacting zone is configured to combine the partially cooled, compressed intermediate gas phase stream and the liquid phase hydrocarbon stream to form the two-phase combined stream.

10. The apparatus of claim 9, wherein the recontacting zone comprises a mixing device configured to receive and mix the partially cooled, compressed intermediate gas phase stream and the liquid phase hydrocarbon stream to form the two-phase combined stream.

11. A method for reforming of hydrocarbons including recovery of products, the method comprising the steps of:

separating a reforming-zone effluent that comprises H₂, C₄⁻

hydrocarbons, and C₅⁺ hydrocarbons including aromatics to form a net gas phase stream that comprises H₂ and C₆⁻

hydrocarbons and a liquid phase hydrocarbon stream that comprises C₅⁺ hydrocarbons;

compressing the net gas phase stream to form a compressed net gas phase stream;

partially condensing and cooling the compressed net gas phase stream to form a partially condensed, compressed net gas phase stream;

separating the partially condensed, compressed net gas phase stream into an intermediate gas phase stream and a first intermediate liquid phase hydrocarbon stream;

combining the intermediate gas phase stream and the liquid phase hydrocarbon stream to extract C₃/C₄ hydrocarbons from the intermediate gas phase stream to the liquid phase hydrocarbon stream and to form a two-phase combined stream;

cooling the two-phase combined stream to form a cooled two-phase combined stream; and

separating the cooled two-phase combined stream to form an H₂-rich stream and a cooled second intermediate liquid phase hydrocarbon stream that is enriched with C₃/C₄ hydrocarbons and further comprises C₅⁺ hydrocarbons.

12. The method of claim 11, wherein separating the reforming-zone effluent comprises separating the reforming-zone effluent in a separation zone, and wherein the method further comprises the step of recycling the first intermediate liquid phase hydrocarbon stream back to the separation zone for further separation.

13. The method of claim 11, further comprising the steps of:

heating at least a portion of the cooled second intermediate liquid phase hydrocarbon stream to form a heated second intermediate liquid phase hydrocarbon stream;

separating the heated second intermediate liquid phase hydrocarbon stream to form a C₅⁺ hydrocarbon-rich reformate stream that comprises primarily C₅⁺ hydrocarbons and a stabilizer gas stream that comprises H₂ and C₄⁻

hydrocarbons;

partially condensing and cooling at least a portion of the stabilizer gas stream to form a partially condensed stabilizer net gas stream; and

separating the partially condensed stabilizer net gas stream to form a C₃/C₄ hydrocarbon-rich LPG stream that comprises primarily C₃/C₄ hydrocarbons and a light ends gas stream that comprises H₂ and C₂⁻

hydrocarbons.

14. The method of claim 13, wherein the step of separating the heated second intermediate liquid phase hydrocarbon stream comprises separating the heated second intermediate liquid phase hydrocarbon stream that has a temperature of from about 150 to about 200°

C.

15. The method of claim 13, wherein the step of separating the heated second intermediate liquid phase hydrocarbon stream comprises separating the heated second intermediate liquid phase hydrocarbon stream that has a pressure of from about 900 to about 1400 kPa gauge.

16. The method of claim 13, wherein the step of separating the partially condensed stabilizer net gas stream comprises separating the partially condensed stabilizer net gas stream that has a temperature of from about −

28 to about 4°

C.

17. The method of claim 13, wherein the step of separating the partially condensed stabilizer net gas stream comprises separating the partially condensed stabilizer net gas stream that has a pressure of from about 700 to about 1,200 kPa gauge.

18. The method of claim 13, further comprising the step of:

removing water from the at least the portion of the stabilizer gas stream prior to the step of partially condensing and cooling.

19. The method of claim 11, further comprising the step of:

removing water from the intermediate gas phase stream prior to the step of combining.

20. A method for reforming of hydrocarbons including recovery of products, the method comprising the steps of:

combining a gas phase stream that comprises H₂ and C₆⁻

hydrocarbons with a liquid phase hydrocarbon stream that comprises C₅⁺ hydrocarbons to extract C₃/C₄ hydrocarbons from the gas phase stream into the liquid phase hydrocarbon stream and to form a two-phase combined stream;

separating the two-phase combined stream in a recontact drum to form an H₂-rich stream that comprises primarily H₂ and an intermediate liquid phase hydrocarbon stream that is enriched with C₃/C₄ hydrocarbons and further comprises C₅⁺ hydrocarbons;

separating the intermediate liquid phase hydrocarbon stream in a stabilizer to form a C₅⁺ hydrocarbon-rich reformate stream that comprises primarily C₅⁺ hydrocarbons and a stabilizer gas stream that comprises H₂ and C₄⁻

hydrocarbons;

partially condensing and cooling at least a portion of the stabilizer gas stream to form a partially condensed stabilizer net gas stream; and

separating the partially condensed stabilizer net gas stream in a separator to form a C₃/C₄ hydrocarbon-rich LPG stream that comprises primarily C₃/C₄ hydrocarbons and a light ends gas stream that comprises H₂ and C₂⁻

hydrocarbons.