The refineries, Puget Sound in Washington, Deer Park and Port Arthur in Texas, and Convent and Norco in Louisiana, originally planned to install new hydrotreating units to meet new sulphur levels specified under updated federal regulations.

But Shell Global Solutions’ (SGS) licensed hydrotreating technology will now be used in the revamp of existing systems. SGS is providing project management, design development and engineering, and procurement, at all five refineries.

Before developing the design, process specialists conducted pilot plant studies for each refinery to determine the best catalyst solution and to set key hydrotreatment operating parameters.

Venture management team leader Richard Gerth, from Shell Oil Products US, said the studies indicated modifications to the refineries would be significant, and that existing hydrotreaters could be revamped to produce ultra-low sulphur diesel.

“We are not just saving the cost of building the new units,” he said.

“Because we are ordering new equipment for five refineries, we have found that bundling the procurement needs together and then going to the market with large orders has resulted in significant financial savings.”

Another advantage of tackling the installations as a single project was that solutions to technical challenges in one hydrotreating unit could be implemented at the others, said Gerth.

“We started with the Puget Sound unit - it is about four months ahead of some of the later refineries - and we can take lessons learned from that site and carry them over to the other refineries. This sequencing has led to significant design efficiencies.”