Our team provided detailed engineering and procurement solutions to allow the Robinson Refinery to meet Tier 3 requirements. Our solutions included modification to the existing gasoline desulfurization unit (GDU) to handle increased rates and a second feed blend while minimizing octane loss. This required the installation of a new naphtha feed system, modifications to the hydrodesulfurization (HDS) reactor, a new HDS reactor feed/effluent exchanger, tray replacement in the existing stabilizer, new splitter bottoms coolers, and modifications to several pumps for new service conditions.
The project objective was to make the changes necessary in preparation for Tier 3 regulations, which reduce sulfur in gasoline from current levels of 30 ppm down to 10 ppm. This project increased the GDU fluidized catalytic cracker (FCC) processing capabilities from 35,600 BPD to 47,000 BPD by adding a second feed blend of saturated gas naphtha and light straight run (LSR).
The increased charge rate required increased catalyst volume in the HDS reactor section to help reduce the sulfur content in the naphtha blended into the gasoline. It also required new equipment and modifications to the existing systems to handle the new processing rates.
The project required a detailed evaluation of the existing GDU, which utilizes Prime G+ process, which is licensed by Axens. This required critical collaboration between the engineering team, client and license provider.
The previous phase of the project was handled by another contractor, presenting a unique challenge to completely align with the process and project scope in order to execute a successful project with minimal design changes.
The project included the structural steel, foundations, piping, instrumentation and electrical components required to execute the project. Our team provided detailed engineering services and procurement.
New splitter bottoms cooler
New HDS feed/effluent exchanger shell
New piping from sat gas plant to GDU
Increased shell side inlet nozzle of HDS feed/effluent exchanger
New naphtha feed filters
New naphtha feed drum
New naphtha feed pumps
Tray replacement in stabilizer 74C-11
Internal reactor modifications in first HDS reactor 74C-6