Energy Efficient New process and improved performance for the Recovery of aromatics

摘要

A method for converting an existing process of liquid-liquid extraction (LLE) based on Solvent sulpholane employs a column lle extraction column, an Extractive (ESC)A Solvent Recovery column (SRC), a column of water washing, Refining (WWC)And a Solvent Regenerator (SRG) in an improved process for the Recovery of aromatic hydrocarbons from a blend of the same with non aromatic hydrocarbons,Where the existing process includes the steps of: (i) introduce a First line through a mixture of hydrocarbons in column carried through a central location of the same; (ii)Enter Through a second line a poor Solvent Free oil from the bottom of the lle in the src column through an Upper location; (iii) transfer through dAnd a third line an extract rich in Aromatic Solvents, Column Bottom come on top of the ESC; (iv) a current Refining Aromatic not withdraw from topThe Fourth column carried through a feed line and a Lower portion of the WWC; (V) the current mix of aromatic extract rich in poor Solvent with a Solvent or a Solvent SecondaryAnd Rich a Side Cut of the src to form a combined current which is Fed to the top of the ESC through a Fifth line; (VI) to withdraw a vapor that leaves the head partAnd top of the ESC and transfer the steam Accumulator is higher than a First Phase separation between a Hydrocarbon phase and an aqueous phase.Where The Hydrocarbon phase is recycled through a Sixth line to a Lower portion of the column with reflux and the aqueous phase is converted into Steam which is transferred through aLine 7 to the src; (vii) transfer a Stream rich in Aromatic Solvent from the bottom of the ESC at a Middle portion of the src through an eighth line; (viii) remove a.Through the src Transfer aromatic and concentrated to a Second Tank Top by a phase separation between an Aromatic phase and an aqueous phase in which removes a part of LAromatic Phase as a product and another part of the Aromatic Phase reflux recycled to the src.Where the conversion includes the steps of: (a) install a Ninth line for introducing a portion of a poor Solvent Free oil from the bottom of the src in a Distilling columnThis modified Extractive (EDC) through a top location,Where the EOC is obtained by the modified ESC; (b) install a Tenth line to introduce an extract rich in Aromatic Solvent column Bottom lle in EDC modified throughS of a Lower location; (c) install an Eleventh line to transfer a non Aromatic Concentrate from the Accumulator higher EDC modified and mixed with a stream of REfinaciu00f3n Aromatic not from the upper part of the column lle; (d) to eliminate the existing line to introduce the three extract rich in Aromatic Solvents, Column Bottom lle in the party sThe Higher EDC modified; (e) delete the existing line to transfer from the six Top reflux Accumulator of the EDC modified column carried through a Lower D locationThe same; and (f) to remove an existing line to introduce the poor Solvent Free oil from the bottom of the src in the bottom line of the column that contains the Aromatic extract Rich lleIn Solvents or remove an existing line to enter the Court, containing Aromatic Solvent Rich side of the src in the bottom line of the column that contains the Aromatic extract lleRich in solvents.