The appetite for residue upgrading through the application of ebullated-bed hydrocracking is growing around the world, as it is a well-established, commercially proven technology offering very high conversion levels and can help, therefore, to minimize the amount of bottoms sent to the bunker fuel pool. Moreover, the attractiveness of ebullated-bed hydrocracking as a technology solution for refiners has been enhanced by the recent trend for greater vacuum residue (VR) feed processing flexibility, which leads to improved refinery crude diversification economics.
Ebullated-bed hydrocracking is a long-established technology that can provide conversion of up to 80% (524°C+) of very refractive VR feeds with high contaminant metals and Conradson carbon residue (CCR) contents. Since ebullated-bed hydrocracking was commercialized in the 1960s, 16 units have been built. In the last four years, its popularity has increased significantly; another six units are planned to be online by 2020.
A Customized Approach to Catalyst Development
Ebullated-bed hydrocrackers are highly customized according to a refiner’s specific objectives and there has been a great deal of innovation in the latest grassroots designs.
Earlier-generation designs were more closely integrated with downstream fluidized catalytic cracking units and the key products required further upgrading to meet the required specifications. In contrast, the design of newer-generation units features an integrated hydrocracker–high-pressure hydrotreater in the same high-pressure loop. This enables direct production of high-value transportation fuels such as ultra-low-sulphur diesel from VR.
Shell currently operates both types of ebullated-bed unit licensed technologies: Axens’ H-OilRC and Chevron Lummus Global’s LC-FINING technology. Additionally, we have more than 40 years’ experience in ebullated-bed catalysts and currently supply customized catalysts to both H-OilRC and LC-FINING units.