New Sulfur Limits for Bunker Fuels: The Challenges and Opportunities for the Refinery Industry

摘要

The demand for bunker fuels (heavy fuel oils) is constantly increasing thanks to the booming shipping industry. Recently, the International Maritime 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% until 2010, 1.0% after 2010, and a further reduction to 0.1% in 2015. The new regulations have raised concerns for 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 the shipping industry is an economic disadvantage, and after-treatment technology such as exhaust scrubbing can only solve part of the problems of meeting emission requirements, desulfurization of bunker fuels is becoming necessity in the refineries. Traditional diesel fuel desulfurization methods including hydrotreating might still be useful, but are less economically feasible than other technologies, e.g., hydrocracking with new catalysts and improved reactor design. This paper will review the technologies for low sulfur bunker fuels production, including hydrotreating and conversion technology, including coking, hydrocracking, visbreaking, oxidative desulfurization, and ultrasound treatment.