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The naphtha is frst hydrotreated to remove sulur and nitrogen

compounds and then sent to a CCR Platforming unit, where

paransand naphthenesare converted to aromatics.

The reormate product rom the CCR Platorming unit is sent to a

debutanizer column within the Platorming unit to strip o the light

ends. Reormate rom the CCR Platorming unit is sent to a reformate

splitter column.

The Craction rom the overheadis sent to the Sulfolane unit or

e!traction o benzene and toluene.

The C" raction rom the bottomo the reformate splitter is clay#

treated and then sent directly to the !ylene recovery section o the

comple!.

The $ulolane unit e!tracts the aromatics rom the reormate splitter

overhead and re%ects a para&nic ra&nate stream. The aromatic

e!tract is clay#treated to remove trace olefns.

'igh#purity benzene and toluene products are recovered in the

benzene-toluene (BT) fractionation section o the comple!.

C! materialrom the bottom o the toluene columnis sent to the

!ylene recovery section o the comple!

Toluene is usually blended with C( and C)* aromatics +(- rom the

overhead o the ( column and charged to a Tatoray unit or the

production o additional !ylenes and benzene.

The e/uent rom the Tatoray unit is sent to a stripper column within

the Tatoray unit to remove light ends.

ter the e/uent is clay#treated, it is sent to the 0T ractionation

section, where the benzene product is recovered and the !ylenes are

ractionated out and sent to the !ylene recovery section.

The overhead material rom the Tatoray stripper or T'1 stripper

column is separated into gas and li2uid products. The overhead gas is

e!ported to the uel gas system, and the overhead li2uid is normally

recycled to the CCR Platorming debutanizer or recovery o residual

benzene

The e/uent rom the Tatora" unitis sent to a stripper column within

the Tatoray unit to remove light ends.

The C"- raction rom the bottom o the reormate splitter is clay#

treated and then charged to a !ylene splitter column.

The overhead rom the !ylene splitter is charged directly to the Pare!

unit.

The bottoms are sent to the (column, where the ( raction is rerun

and then recycled to the Tatoray or T'1 unit.

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3 the comple! has no Tatoray or T'1 unit, the (- material is usually

blended into gasoline or uel oil.

The !ylene splitter bottoms are then sent to an o#4 column where high#

purity ortho#!ylene product is recovered overhead.

The bottoms rom the o#4 column are then sent to the ( column.

ny residual toluene in the Pare! eed is e!tracted along with the para#

!ylene, ractionated out in the fnishing column within the Pare! unit,

and then recycled to the Tatoray or T'1 unit.

The ra&nate is sent to the 3somar unit, where additional para#!ylene is

produced by reestablishing an e2uilibrium distribution o !ylene

isomers.

ny ethylbenzene in the Pare! ra&nate is either converted to

additional !ylenes or deal5ylated to benzene, depending on the type o

3somar catalyst used.

The e/uent rom the 3somar unit is sent to a deheptanizer column.

The bottoms rom the deheptanizer are clay#treated and recycled bac5

to the !ylene splitter.

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The overhead rom the deheptanizer is split into gas and li2uid

products.