Conventional hydrocracking is a well-known process designed to convert crude oil fractions boiling in the vacuum gas oil (VGO) range into transportation fuels such as diesel, jet fuel and naphtha, depending on the operator's objectives. While hydrocrackers have an excellent track record processing VGOs and lighter feedstocks, feedstocks heavier than VGO pose significant challenges resulting in diminished unit performance and processing efficiency. Therefore, it has long been the objective of Saudi Aramco to enable its Riyadh Refinery hydrocracker to handle more Demetallized Oil (DMO) and much work has been carried out over the last few years to enhance this capability through process and catalyst modifications.
Saudi Aramco's R&DC and JGC C&C, a leading catalyst developer and manufacturer in Japan, have also collaborated to develop a catalyst system to enable the Riyadh Refinery hydrocracking unit to process a blend of VGO and DMO, targeting the extended cycle while increasing or maintaining distillate yields and quality.
After extensive R&D work, in which over 85 catalysts were designed, prepared and pilot plant tested for over 2,076 days, some formulations, were identified as candidates for scale-up and commercialization. The R&D phase of the project was started in 2007 and completed in 2010 and four potential catalysts were identified for scale-up and commercialization. The Saudi Aramco and JGC C&C team invited UOP into the collaboration to jointly demonstrate the catalyst in a recycle unit and then deploy the catalysts at the Riyadh Refinery. The joint effort that followed involved significant evaluation and modification of the catalyst composition based on pilot plant assessment, which led to the successful deployment of the formulation that best matched the needs of this processing unit. Extensive work was conducted to determine the best placement of the selected catalyst prototype in the unit.
The catalyst was loaded into the Riyadh Refinery hydrocracking unit in May 2014 and has been performing exceptionally well.