Turnkey Naphtha Splitter Revamp to a Dual Dividing Wall Column

The challenge

MRPL’s CDU-2 naphtha splitter needed to deliver tighter, more consistent light, medium, and heavy naphtha cuts — better feed for the downstream Isomerization and Continuous Catalytic Reformer (CCR) units — without adding energy or a new column, and without a long shutdown. A conventional splitter struggles to make three on-spec cuts from a single tower, and improving separation the conventional way usually means more reboiler duty. MRPL needed sharper separation, wider operating flexibility, and a stable control scheme, achieved inside the existing column during a planned turnaround.

The solution: a Dual Dividing Wall Column, delivered turnkey

DWC Innovations converted the existing naphtha splitter into a Dual Dividing Wall Column using its proprietary DWC-Prime technology — and delivered the entire project itself, from concept to commissioning. DWCI’s single-vendor scope covered licensing of the DWC-Prime technology, basic and detailed engineering of the unit, supply and installation of the proprietary tower internals, modification of the column and its connected piping, and on-site supervision through the turnaround. Two dividing walls let one column do the work of a conventional column sequence: one wall sharpens the separation while the second removes the extra trays a conventional arrangement would otherwise need. Because the revamp reused the existing column shell, it was executed inside the plant’s planned turnaround window.

What the revamp delivers

The Dual DWC now produces three sharper naphtha cuts — light, medium, and heavy — from a single column, and it does so with no change in reboiler duty: better separation and cleaner products without spending more energy. The tighter cuts improve feed preparation for the downstream Isomerization and CCR units, relieving those units and letting them run more efficiently. The column also gained wider operational flexibility and a stable, robust control scheme, and its performance guarantees were tested and passed in commercial operation in 2026.

Why it matters

This project shows that a naphtha splitter can be re-architected into a multi-cut Dual DWC — sharper products, more flexibility, and better downstream feed — with no energy penalty and inside an existing column, delivered by a single technology partner from feasibility to start-up. Because the light, medium, and heavy cuts are cleaner, the Isomerization and CCR units downstream see better-prepared feed, debottlenecking the whole naphtha train.

Talk to us about your naphtha splitter →Read the original press release →