(59a) New Sulfur Limits for Bunker Fuels: The Challenges and Opportunities for the Refinery Industry

The demand for bunker fuels (heavy fuel oils) is constantly increasing thanks to the booming shipping industry. Recently, the International Marine Organization (IMO) approved the regulations for a decrease of sulfur limits of marine bunker fuels from 4.5% globally to 3.5% by 2012 and to 0.5% in 2020-2025. For the Emission Control area (ECAs) in the U.S., which includes California, the Pacific Coast, and other areas, the sulfur level requirements are more stringent: 1.5% to 2010, 1.0% after 2010, and further down to 0.1% until 2015. The new regulations have raised concerns on the availability, cost and quality of lower sulfur bunker fuels, and this brings a lot of challenges for refinery industry. Since shifting to conventional diesel fuel for shipping industry is in economic disadvantage, and after-treatment technology such as scrubbing can only solve part of the problems for emission requirements, desulfurization of bunker fuels is necessary in the refineries. Traditional diesel fuel desulfurization method by hydrotreating might still be useful, but less economic feasible than other technologies, e.g., hydrocracking and visbreaking. This paper will review the technologies for low sulfur bunker fuels production, including hydrotreating and conversion technology, including coking, hydrocracking, visbreaking, and ultrasound treatment.