We Claim:
1. Process for the separation of a feedstock comprising benzene, toluene and
5 compounds having 8 or more carbon atoms, in a separation device comprising at least one
reformate column (C1), one aromatics extraction unit (P1) and one transalkylation unit (P4), the effluents from the said units being separated in the following distillation columns: benzene column (C9), toluene column (C10) and stabilization column (C11), the said process comprising the following stages:
10 the toluene column (C10) is fed directly with a C7+ cut resulting from the bottom of the stabilization column (C11) positioned downstream of the transalkylation unit (P4) in order to withdraw a top product from the toluene column (C10) enriched in benzene and in toluene and a bottom product from the toluene column (C10) enriched in compounds having 8 or more carbon atoms,
15 the benzene column (C9) is fed with the top product from the toluene column (C10) in order to withdraw a benzene-enriched top product from the benzene column (C9) and a toluene-enriched bottom product from the benzene column (C9), and
the transalkylation unit (P4) is fed with the toluene-enriched bottom product from the benzene column (C9),
20 in which the toluene column (C10) is fed with an essentially aromatic cut resulting from the aromatics extraction unit (P1), the feeding of the toluene column (C10) resulting from the aromatics extraction unit (P1) being carried out separately from and above the feeding of the toluene column (C10) resulting from the bottom of the stabilization column (C11), or
25 in which the benzene column (C9) is fed with the essentially aromatic cut resulting from the aromatics extraction unit (P1) as a mixture with or separately from the top product from the toluene column (C10).
2. Separation process according to Claim 1, in which the toluene column (C10) is
30 additionally fed with a top product from the purification column (C6) as a mixture with or
separately from the C7+ cut resulting from the bottom of the stabilization column (C11).
3. Separation process according to Claim 1, in which the transalkylation unit (P4) is
additionally fed with a top product from the purification column (C6) as a mixture with or
35 separately from the bottom product from the benzene column (C9).
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4. Separation process according to any one of the preceding claims, in which the
separation device additionally comprises a para-xylene separation unit (P2) and a xylenes
isomerization unit (P3), the said effluents being separated in the following additional
distillation columns: xylenes column (C2), heavy aromatics column (C3), raffinate column
5 (C4), extract column (C5), purification column (C6), deheptanizer (C7) and stripper (C8).
5. Separation process according to Claim 4, in which only the xylenes column (C2) and
the heavy aromatics column (C3) feed the transalkylation unit (P4) with C9+ aromatic
compounds.
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6. Separation process according to any one of the preceding claims, in which the
reformate column (C1) is fed with the feedstock in order to produce a C7- cut at the top of
the reformate column (C1), and the aromatics extraction unit (P1) is fed with the C7- cut in
order to extract paraffinic compounds from the C7- cut and to produce the essentially
15 aromatic cut.
7. Separation process according to any one of the preceding claims, the operating
conditions of the benzene column (C9) are as follows:
temperature of 130°C to 180°C at the reboiler, from 70°C to 130°C at the condenser; 20 pressure: between 0.1 MPa and 0.5 MPa; and
the benzene column (C9) comprising between 35 and 55 theoretical plates.
8. Separation process according to any one of the preceding claims, the operating
conditions of the toluene column (C10) are as follows:
25 temperature of 130°C to 260°C at the reboiler, from 50°C to 200°C at the condenser; pressure: between 0.05 MPa and 1 MPa; and the toluene column (C10) comprising between 30 and 55 theoretical plates.
9. Device for the separation of a feedstock comprising benzene, toluene and
30 compounds having 8 or more carbon atoms, the separation device comprising at least one
reformate column (C1), one aromatics extraction unit (P1) and one transalkylation unit (P4), the separation device additionally comprising the following columns for the distillation of the effluents from the said units: benzene column (C9), toluene column (C10) and stabilization column (C11), 35 the toluene column (C10) being appropriate for being fed with a C7+ cut resulting from the bottom of the stabilization column (C11) positioned downstream of the
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transalkylation unit (P4) and for delivering a top product from the toluene column (C10) enriched in benzene and in toluene and a bottom product from the toluene column (C10) enriched in compounds having 8 or more carbon atoms,
- the benzene column (C9) being appropriate for being fed with the top product from
5 the toluene column (C10) and for delivering a benzene-enriched top product from the
benzene column (C9) and a toluene-enriched bottom product from the benzene column (C9), and
- the transalkylation unit (P4) being appropriate for treating the toluene-enriched bottom
product from the benzene column (C9),
10 in which the toluene column (C10) is appropriate for being fed with an essentially aromatic cut resulting from the aromatics extraction unit (P1), the feeding of the toluene column (C10) resulting from the aromatics extraction unit (P1) being carried out separately from and above the feeding of the toluene column (C10) resulting from the bottom of the stabilization column (C11), or
15 in which the benzene column (C9) is appropriate for being fed with the essentially aromatic cut resulting from the aromatics extraction unit (P1) as a mixture with or separately from the top product from the toluene column (C10).
10. Separation device according to Claim 9, in which the toluene column (C10) is
20 appropriate for being fed with a top product from a purification column (C6) as a mixture
with or separately from the C7+ cut resulting from the bottom of the stabilization column (C11).
11. Separation device according to Claim 9, in which the transalkylation unit (P4) is
25 appropriate for being fed with a top product from a purification column (C6) as a mixture
with or separately from the bottom product from the benzene column (C9).
12. Separation device according to any one of Claims 9 to 11, additionally comprising a
para-xylene separation unit (P2), a xylenes isomerization unit (P3) and the following
30 additional columns for the distillation of the said effluents: xylenes column (C2), heavy aromatics column (C3), raffinate column (C4), extract column (C5), purification column (C6), deheptanizer (C7) and stripper (C8).
13. Separation device according to any one of Claims 9 to 12, in which the reformate
35 column (C1) is appropriate for being fed with the feedstock in order to produce a C7- cut at
the top of the reformate column (C1), and the aromatics extraction unit (P1) is appropriate
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for being fed with the C7- cut in order to extract paraffinic compounds from the C7- cut and to produce the essentially aromatic cut.
14. Separation device according to any one of Claims 9 to 13, in which the benzene 5 column (C9) is appropriate for being used under the following operating conditions: temperature of 130°C to 180°C at the reboiler, from 70°C to 130°C at the condenser; pressure: between 0.1 MPa and 0.5 MPa; and the benzene column (C9) comprising between 35 and 55 theoretical plates.
10 15. Separation device according to any one of Claims 9 to 14, in which the toluene column (C10) is appropriate for being used under the following operating conditions:
temperature of 130°C to 260°C at the reboiler, from 50°C to 200°C at the condenser;
pressure: between 0.05 MPa and 1 MPa; and
the toluene column (C10) comprising between 30 and 55 theoretical plates. 15
Dated this 02 day of May 2019
- Digitally signed -
(R R Nair)
Reg. No.: IN/PA – 121
Of De Penning & De Penning
Agent for the Applicants
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