Integrated process for maximizing recovery of aromatics

Patent metadata

Field	Value
Publication number	US-11040926-B2
Application number	US-201916517865-A
Country	US
Kind code	B2
Filing date	Jul 22, 2019
Priority date	Jul 22, 2019
Publication date	Jun 22, 2021
Grant date	Jun 22, 2021

Abstract

An integrated process for maximizing recovery of aromatics is provided. The process comprises passing at least a portion of a xylene column bottoms stream to a heavy aromatics column to provide a heavy aromatics column bottoms stream comprising C9+ aromatics and a heavy aromatics column overhead stream. The heavy aromatics column bottoms stream is passed to a second stage hydrocracking reactor of a two-stage hydrocracking reactor. In the second stage hydrocracking reactor, the heavy aromatics column bottoms stream is hydrocracked in the presence of a hydrocracking catalyst and hydrogen to provide a hydrocracked effluent stream.

First claim

The invention claimed is:

1. An integrated process for maximizing recovery of aromatics, comprising:
passing at least a portion of a xylene column bottoms stream to a heavy aromatics column to provide a heavy aromatics column bottoms stream comprising C 9+ aromatics and a heavy aromatics column overhead stream; and
hydrocracking the heavy aromatics column bottoms stream in a second stage hydrocracking reactor of a two-stage hydrocracking reactor in the presence of a hydrocracking catalyst and hydrogen to provide a hydrocracked effluent stream.

2. The process of claim 1 further comprising:
hydrocracking a hydrocarbonaceous feed in a first stage hydrocracking reactor in the presence of a first stage hydrocracking catalyst and hydrogen to provide a first stage hydrocracked effluent stream;
separating the first stage hydrocracked effluent stream in a fractionation column to provide an overhead stream and a bottoms stream comprising unconverted oil;
hydrocracking the bottoms stream comprising unconverted oil and the heavy aromatics column bottoms stream in the second stage hydrocracking reactor in the presence of a second stage hydrocracking catalyst and hydrogen to provide a second stage hydrocracked effluent stream; and
passing the second stage hydrocracked effluent stream to the fractionation column.

3. The process of claim 2 further comprising:
combining the heavy aromatics column bottoms stream with the bottoms stream comprising unconverted oil to provide a combined stream; and
passing the combined stream to the second stage hydrocracking reactor.

4. The process of claim 1 , wherein each stage of the two-stage hydrocracking reactor comprises one or more beds adaptable to contain the hydrocracking catalyst.

5. The process of claim 4 further comprising passing the heavy aromatics column bottoms stream in between the one or more beds of the hydrocracking catalyst.

6. The process of claim 2 further comprising:
reforming a naphtha feed stream and a heavy naphtha stream taken from the fractionation column in a reforming unit in the presence of hydrogen and a reforming catalyst to provide a reformate effluent stream;
passing the reformate effluent stream to a reformate splitter to provide a reformate splitter overhead stream comprising C 7− hydrocarbons and a reformate splitter bottoms stream comprising C 8+ aromatics; and
passing the reformate splitter bottoms stream to a xylene column to provide a xylene column overhead stream comprising a mixture of xylenes and the xylene column bottoms stream.

7. The process of claim 6 further comprising:
passing the reformate splitter overhead stream to an extraction unit to provide a benzene rich extract stream;
passing the benzene rich extract stream and a transalkylated effluent stream to a benzene column to recover benzene in an overhead stream and provide a benzene column bottoms stream;
passing the benzene column bottoms stream to a toluene column to provide a toluene rich overhead stream and a toluene column bottoms stream;
passing the toluene rich overhead stream and a heavy aromatics column overhead stream to a transalkylation unit comprising transalkylation catalyst to produce the transalkylated effluent stream; and
passing the toluene column bottoms stream to the xylene column.

8. The process of claim 6 further comprising:
passing the xylene column overhead stream to a paraxylene separation unit to separate paraxylene and provide a paraxylene lean stream;
passing the paraxylene lean stream to an isomerization unit to provide an isomerized effluent stream; and
passing the isomerized effluent stream to the xylene column.

9. The process of claim 1 further comprising:
passing the xylene column bottoms stream to an ortho-xylene column to recover ortho-xylene in an overhead stream and provide an ortho-xylene column bottoms stream; and
passing the ortho-xylene column bottoms stream to the heavy aromatics column to provide the heavy aromatics column bottoms stream.

10. The process of claim 1 , wherein the stream to the xylene column comprises one or more of a reformate splitter bottoms stream, a toluene column bottoms stream, and an isomerized effluent stream.

11. The process of claim 1 further comprising at least one of:
sensing at least one parameter of the integrated process for maximizing recovery of aromatics and generating a signal or data from the sensing;
generating and transmitting a signal; or
generating and transmitting data.

12. An integrated process for maximizing recovery of aromatics, comprising:
passing a stream to a xylene column to provide a xylene column overhead stream comprising a mixture of xylenes and a xylene column bottoms;
passing at least a portion of the xylene column bottoms stream to a heavy aromatics column to provide a heavy aromatics column bottoms stream comprising C 9+ aromatics and a heavy aromatics column overhead stream; and
hydrocracking the heavy aromatics column bottoms stream and an unconverted oil stream in a second stage hydrocracking reactor of a two-stage hydrocracking reactor to provide a second stage hydrocracked effluent stream.

13. The process of claim 12 further comprising:
hydrocracking a hydrocarbonaceous feed in a first stage hydrocracking reactor in the presence of the hydrocracking catalyst and hydrogen to provide a first stage hydrocracked effluent stream;
combining the second stage hydrocracked effluent stream with the first stage hydrocracked effluent stream to provide a combined hydrocracked effluent stream; and
fractionating the combined hydrocracked effluent stream in a fractionation column to provide an overhead stream and the unconverted oil stream.

14. The process of claim 12 further comprising:
passing the xylene column overhead stream to a paraxylene separation unit to separate paraxylene and provide a paraxylene lean stream; and
passing the paraxylene lean stream to an isomerization unit to provide an isomerized effluent stream; and
passing the isomerized effluent stream to the xylene column.

15. The process of claim 13 further comprising:
reforming a naphtha feed stream and a heavy naphtha stream taken from the fractionation column in a reforming unit in the presence of hydrogen and a reforming catalyst to provide a reformate effluent stream; and
passing the reformate effluent stream to a reformate splitter to provide a reformate splitter overhead stream comprising C 7− hydrocarbons and a reformate splitter bottoms stream comprising C 8+ aromatics; and
passing the reformate splitter bottoms stream to the xylene column.

16. The process of claim 15 further comprising:
passing the reformate splitter overhead stream to an extraction unit to provide a benzene rich extract stream;
passing the benzene rich extract stream and a transalkylated effluent stream to a benzene column to recover benzene in an overhead stream and provide a benzene column bottoms stream;
passing the benzene column bottoms stream to a toluene column to provide a toluene rich overhead stream and a toluene column bottoms stream;
passing the toluene rich overhead stream and the heavy aromatics column overhead stream to a transalkylation unit comprising transalkylation catalyst to produce the transalkylated effluent stream; and
passing the toluene column bottoms stream to the xylene column.

17. The process of claim 12 , wherein each stage of the two-stage hydrocracking unit comprises one or more beds adaptable to contain a hydrocracking catalyst.

18. The process of claim 17 further comprising passing the heavy

Assignees

• Uop Llc

Inventors

• Pandey Gautam
• Mani Krishna
• Bisht Deepak
• Jani Priyesh Jayendrakumar
• Dalal Vikrant Vilasrao
• Rokkam Ram Ganesh

Classifications

• C10G47/00 Primary

  Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions (C10G15/00 takes precedence; destructive hydrogenation of non-melting solid carbonaceous or similar materials C10G1/06) · CPC title

• C07C6/126

  of more than one hydrocarbon · CPC title

• C07C5/2702

  Catalytic processes not covered by C07C5/2732 - C07C5/31; Catalytic processes covered by both C07C5/2732 and C07C5/277 simultaneously · CPC title

• C07C7/04

  by distillation · CPC title

• C10G2400/30

  Aromatics · CPC title