Articles

Maximize margins in a light naphtha isomerization unit by producing C6 products : Hydrocarbon Processing

DWC Innovations / 08 February, 2021 / Articles

The light naphtha isomerization process efficiently converts low grade straight run naphtha components to high RON branched chain components. Typical isomerization units have deisohexanizer column (DIH) that separates light and heavy isomerate along with a side cut recycle stream to the isomerization reactor. The DIH column can be revamped to DWC prime which produces an additional 4th cut of C6 products (Food Grade Hexane/ Polymer grade hexane/ Isohexane /Special boiling point solvents). This revamp not only increases the profitability of Isom unit, but also increases the capacity of Isom unit by more than 20%. Typical revamp payback is 2-12 months.

Read the complete article in Feb 2021 issue of Hydrocarbon Processing.

Dividing wall distillation columns : PTQ

DWC Innovations / 12 July, 2022 / Articles

Dividing wall distillation columns are now widely accepted in the industry. The existing naphtha complex became a bottleneck in the refinery. The naphtha complex consisted of hydrotreating, naphtha splitters, Isomerization and CCR units. Full range naphtha from crude distillation unit is stabilized in naphtha stabilizer then goes as feed to naphtha splitter. Light naphtha (C5/C6) is feed to Isomerization unit, bottoms C7 is the feed to CCR unit. A C6 cut is drawn as side cut to avoid benzene and precursors in the CCR feed.

Space constraints and strict product requirements led to the dividing wall distillation technology as the most effective option for revamp. Besides energy optimization, DWC technology provided a capacity increase of more than 40% over the use of high capacity internals.

Reprinted from PTQ Q1 2020.

Introduction to Dividing Wall Columns : CEP

DWC Innovations / 25 March, 2021 / Articles

This article provides an introduction to Dividing wall columns (DWCs). These distillation columns can separate mixtures of several components into three or more high-purity streams. A DWC requires much less energy, capital investment, and plant space than conventional columns in series or parallel configurations. In fact, DWCs can have 20–30% lower capital cost requirements than conventional tower designs.

Conventional distillation columns are an integral part of the refining and chemical industries. Introduction of dividing wall columns for revamp of existing columns to improve separation efficiency is part of a larger push to intensify processes in these industries. Process intensification (PI) targets dramatic improvements in cost and energy efficiencies by rethinking traditional operation schemes. A DWC is one example of an intensified technology. Read more..