CN-122029141-A - For recovery of C2、C3Or C4Process for one or more of olefins

Abstract

One or more of the C 2 、C 3 or C 4 olefins may be recovered by a process that may include compressing and cooling a gaseous feed stream to produce a first compressed and cooled feed stream, further cooling the first compressed and cooled feed stream by heat exchange with a bottoms stream to produce a second compressed and cooled feed stream, separating the second compressed and cooled feed stream into a first residual vapor stream and a first liquid residual stream, cooling the first residual vapor stream in a cold box to produce a cooled first residual stream, separating the cooled first residual stream into a second residual vapor stream and a second liquid residual stream, and passing at least a portion of the first liquid residual stream and at least a portion of the second liquid residual stream to a fractionation system to produce at least an overhead vapor stream, a liquid recycle stream, and a bottoms stream. The gaseous feed stream may comprise at least 70 wt% of the combination of C 2 、C 3 and C 4 components, and cooling of the gaseous feed stream may be performed by heat exchange with a cooling fluid having a temperature of 0 ℃ to 70 ℃.

Inventors

• ZHANG YUE
• B. al SAR
• J. Holderness
• J. J. Dylan
• A. M. McNally
• M. T. Pratz
• M - A - Cogswell

Assignees

• 陶氏环球技术有限责任公司

Dates

Publication Date

20260512

Application Date

20240917

Priority Date

20230918

Claims (15)

1. 1. A process for recovering one or more of C 2 、C 3 or C 4 olefins, the process comprising: Compressing and cooling a gaseous feed stream to produce a first compressed and cooled feed stream, wherein the gaseous feed stream comprises at least 70 wt% of a combination of C 2 、C 3 and C 4 components, and wherein the cooling of the gaseous feed stream is by heat exchange with a cooling fluid having a temperature of 0 ℃ to 70 ℃; Further cooling the first compressed and cooled feed stream by heat exchange with a bottoms stream to produce a second compressed and cooled feed stream; said second compressed and cooled feed stream is separated into a first residual vapor stream and a first liquid residual stream; cooling the first residual vapor stream in a cold box to produce a cooled first residual stream; said cooled first residual stream is separated into a second residual vapor stream and a second liquid residual stream; At least a portion of the first liquid residue stream and at least a portion of the second liquid residue stream are passed to a fractionation system to produce at least an overhead vapor stream, a liquid recycle stream, and a bottom stream.
2. 2. The process of any preceding claim, further comprising reducing the pressure of the bottoms stream upstream of the heat exchange of the bottoms stream with the first compressed and cooled feed stream.
3. 3. The method of claim 2, wherein reducing the pressure of the bottoms stream at least partially vaporizes the bottoms stream.
4. 4. The process of any preceding claim, further comprising heat exchanging the bottoms stream with a process stream.
5. 5. The method of claim 4, wherein the heat exchange with the process stream is upstream of the pressure reduction of the bottoms stream.
6. 6. The method of claim 4, wherein the process stream is an alkane feed stream fed to an olefin production process that forms the gaseous feed stream.
7. 7. The method of claim 6, wherein the heat exchange of the process stream with the bottom stream at least partially vaporizes the process stream.
8. 8. The process of any preceding claim, wherein the first compressed and cooled feed stream has a pressure of from 15 bar to 100 bar.
9. 9. The process of any preceding claim, wherein the fractionation system is operated at a pressure of from 15 bar to 100 bar.
10. 10. The process of any preceding claim, further comprising separating the bottoms stream into at least two streams downstream of the heat exchange of the bottoms stream with the first compressed and cooled feed stream.
11. 11. The method of any preceding claim, wherein the fractionation system comprises a two-stage fractionation system.
12. 12. The process of any preceding claim, further comprising passing at least a portion of the second residual vapor stream and at least a portion of the second liquid residual stream as a coolant through the cold box.
13. 13. The process of any preceding claim, further comprising passing the overhead vapor stream through the cold box.
14. 14. The method of any preceding claim, further comprising passing the liquid recycle stream through the cold box.
15. 15. The process of any preceding claim, further comprising combining the liquid recycle stream with the gaseous feed stream.

Description

Process for recovering one or more of C 2、C3 or C 4 olefins Cross Reference to Related Applications The present application claims the benefit of U.S. provisional application serial No. 63/583,444, filed on 18, 9, 2023, the contents of which are incorporated herein in their entirety. Technical Field Embodiments described herein relate generally to chemical processing, and more particularly to product recovery in chemical processing. Background Ethylene, ethane, propylene, propane, and/or heavier hydrocarbons may be recovered from various gas streams including natural gas, refinery gas, syngas, or combinations thereof obtained from coal, crude oil, naphtha, oil shale, steam crackers, catalytic crackers, or combinations thereof. Cryogenic expansion processes are widely used to recover condensable product gases from non-condensable or difficult to condense gases because it provides start-up simplicity, operational flexibility, good efficiency and reliability. Disclosure of Invention While conventional recovery processes may be used to recover ethylene, ethane, propylene, propane, and/or heavier hydrocarbons from various gas streams, these processes are generally relatively inefficient, requiring high heat load costs to cool the material to a condensable temperature. Accordingly, there is a continuing need for improved energy efficient recovery methods for recovering one or more of C 2、C3, which may be met by embodiments of the systems and methods described in the present disclosure. Embodiments of the present disclosure relate to processes for recovering one or more of C 2、C3 or C 4 olefins, wherein the pressure in several streams is relatively elevated compared to conventional processes. In particular, the pressure of the compressed feed stream is relatively high and the operating pressure of the fractionation system used to form a bottoms stream that is heat exchanged with the feed stream is relatively high. Such a configuration may enable recovery of condensable product gases from non-condensable or difficult-to-condense gases. As described herein, fractionation systems at high pressures are typically capable of reducing the operating temperature, and therefore, in some embodiments, crude propylene can be used as a refrigerant to cool the warmed cracked gas. In one or more embodiments, this result may reduce the refrigerant requirements of the cold box and achieve better heat integration. In accordance with one or more embodiments disclosed herein, one or more of the C 2、C3 or C 4 olefins can be recovered by a process that can include compressing and cooling a gaseous feed stream to produce a first compressed and cooled feed stream, further cooling the first compressed and cooled feed stream by heat exchange with a bottoms stream to produce a second compressed and cooled feed stream, separating the second compressed and cooled feed stream into a first residual vapor stream and a first liquid residual stream, cooling the first residual vapor stream in a cold box to produce a cooled first residual stream, separating the cooled first residual stream into a second residual vapor stream and a second liquid residual stream, and transferring at least a portion of the first liquid residual stream and at least a portion of the second liquid residual stream to a fractionation system to produce at least an overhead vapor stream, a liquid recycle stream, and a bottoms stream. The gaseous feed stream may comprise at least 70 wt% of the combination of C 2、C3 and C 4 components, and cooling of the gaseous feed stream may be performed by heat exchange with a cooling fluid having a temperature of 0 ℃ to 70 ℃. It is to be understood that both the foregoing summary and the following detailed description present embodiments of the technology, and are intended to provide an overview or framework for understanding the nature and character of the technology as it is claimed. The accompanying drawings are included to provide a further understanding of the technology, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments and together with the description serve to explain the principles and operations of the technology. Further, the drawings and description are meant to be illustrative only and are not intended to limit the scope of the claims in any way. Additional features and advantages of the inventive technique disclosed herein will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the inventive technique as described herein, including the detailed description which follows, the claims, as well as the appended drawings. Drawings The following detailed description of certain embodiments of the present disclosure can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals an