Integrated propane dehydrogenation process

Patent metadata

Field	Value
Publication number	US-10450241-B2
Application number	US-201715706266-A
Country	US
Kind code	B2
Filing date	Sep 15, 2017
Priority date	Sep 16, 2016
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

Processes and systems for the integrated production of propylene and an alkylate, such as cumene, may include feeding a hydrocarbon feedstock containing propane to a propane dehydrogenation reaction zone to convert a portion of the propane to propylene. The propylene is separated in a separation system to form a polymer-grade propylene stream, a low purity propylene stream, and a propane stream. The low purity propylene stream is then fed to an alkylation reaction zone where the propylene is reacted to produce an alkylated product and generate a low pressure steam. The low pressure steam may then be fed to the separation system as a heat source, integrating the dehydrogenation system and the alkylation system.

First claim

What is claimed:

1. A process for the production of cumene comprising:
feeding a hydrocarbon feedstock comprising propane to a propane dehydrogenation reaction zone, converting a portion of the propane to propylene, forming a dehydrogenated effluent;
separating the dehydrogenated effluent in a separation system, forming a polymer-grade propylene stream, a low purity propylene stream, and a propane stream;
feeding the low purity propylene stream to an alkylation reaction zone, wherein propylene is reacted with benzene to concurrently produce an alkylated product comprising cumene and generate a low pressure steam stream; and
feeding the low pressure steam stream to the separating step as a heat source.

2. The process of claim 1 , further comprising recycling the propane stream to the propane dehydrogenation reaction zone.

3. The process of claim 1 , further comprising separating the alkylated product into one or more of a benzene stream, a C3 stream, a cumene product stream, and a heavies effluent, wherein the C3 stream comprises one or more of propane and propylene.

4. The process of claim 3 , wherein the separating the alkylated product comprises recovering the C3 stream at a higher pressure than an operating pressure of the propane dehydrogenation reaction zone.

5. The process of claim 4 , further comprising recycling the C3 stream to the propane dehydrogenation reaction zone as a vapor.

6. The process of claim 5 , wherein the recycling is performed without pressurization or liquefaction.

7. The process of claim 1 , wherein the low pressure steam stream is at a temperature in a range of 100° C. to 120° C. and a pressure of less than or equal to 1 bar.

8. The process of claim 1 , wherein the separation system comprises a low pressure separation column and a high pressure separation column, the process further comprising feeding a first portion of the dehydrogenated effluent to the low pressure separation column and feeding a second portion of the dehydrogenated effluent to the high pressure separation column.

9. The process of claim 8 , wherein a feed ratio of the first portion of the dehydrogenated effluent and the second portion of the dehydrogenated effluent is in a range of 1:1 to 5:1.

10. The process of claim 8 , further comprising operating the low pressure separation column at a temperature in a range of 5° C. to 25° C. and a pressure in a range of 4 barg to 10 barg and operating the high pressure separation column at a temperature in a range of 25° C. to 80° C. and a pressure in a range of 12 barg to 26 barg.

11. The process of claim 8 , further comprising producing a propylene product comprising at least 98 wt % propylene from the low pressure separation column, and producing a propylene product comprising 60-95 wt % propylene from the high pressure separation column.

12. The process of claim 1 , further comprising:
concurrently generating a high pressure steam stream in the propane dehydrogenation reaction zone; and
feeding the high pressure steam stream to the alkylation reaction zone as a heat source.

Assignees

• Lummus Technology Inc
• Lummus Technology Inc

Inventors

• Panditrao Sunil Shashikant
• Ram Sanjeev

Classifications

• C07C2/66 Primary

  Catalytic processes · CPC title

• C07C5/333

  Catalytic processes · CPC title

• Y02P20/582

  Recycling of unreacted starting or intermediate materials · CPC title

• C07C7/005

  Processes comprising at least two steps in series · CPC title

• B01J19/245

  placed in series · CPC title