Abstract: Methods and apparatuses for extractive distillation using internal addition of steam to an extractive distillation column from a reboiler are described herein. The apparatuses include an extractive distillation column, a reboiler (for example, a kettle reboiler) coupled to the extractive distillation column, and a steam input line. The steam input line is coupled to an internal steam sparger device of the reboiler. Methods utilizing the apparatuses to perform extractive distillation of a hydrocarbon feed stream are also described herein.

Abstract: In various embodiments, the present disclosure describes processes and systems for recovery of styrene from a styrene-rich feedstock. The processes and systems maintain performance of an extractive solvent used in the styrene recovery. In general, the processes include introducing a styrene-rich feedstock to an extractive distillation column, removing a styrene-rich stream from the extractive distillation column, introducing the styrene-rich stream to a solvent recovery column, removing a styrene-lean stream from the solvent recovery column, separating and treating a portion of the styrene-lean stream to form a treated extractive solvent and recycling the treated extractive solvent. In some embodiments, the treating process also includes steam stripping. Styrene-recovery systems including an extractive distillation column, a solvent recovery column, a solvent treatment apparatus having at least one equilibrium stage and a continuous circulation loop connecting these components are also disclosed herein.

Abstract: Methods and apparatuses for extractive distillation using internal addition of steam to an extractive distillation column from a reboiler are described herein. The apparatuses include an extractive distillation column, a reboiler (for example, a kettle reboiler) coupled to the extractive distillation column, and a steam input line. The steam input line is coupled to an internal steam sparger device of the reboiler. Methods utilizing the apparatuses to perform extractive distillation of a hydrocarbon feed stream are also described herein.

Abstract: In various embodiments, the present disclosure describes processes and systems for recovery of styrene from a styrene-rich feedstock. The processes and systems maintain performance of an extractive solvent used in the styrene recovery. In general, the processes include introducing a styrene-rich feedstock to an extractive distillation column, removing a styrene-rich stream from the extractive distillation column, introducing the styrene-rich stream to a solvent recovery column, removing a styrene-lean stream from the solvent recovery column, separating and treating a portion of the styrene-lean stream to form a treated extractive solvent and recycling the treated extractive solvent. In some embodiments, the treating process also includes steam stripping. Styrene-recovery systems including an extractive distillation column, a solvent recovery column, a solvent treatment apparatus having at least one equilibrium stage and a continuous circulation loop connecting these components are also disclosed herein.