A review of coke and anode desulfurization

Abstract

During calcination, petroleum coke desulfurizes depending on the sulfur content and final temperature. This has a negative effect on coke properties such as real density, porosity, and reactivity. Additional sulfur loss occurs during anode baking and this can further deteriorate anode properties such as density and reactivity. The sulfur level of high sulfur cokes used by the calcining industry has increased since 2003. Although the average sulfur content of cokes used by smelters has not increased significantly due to environmental limits, the difference in sulfur level of cokes used in blends has increased. Calciners must avoid "over-calcining" high sulfur cokes and smelters must be wary of additional desulfurization during baking. This paper presents a review of past and recent data on coke and anode desulfurization, and gives recommendations on how to best counter the problems that can arise from use of higher sulfur cokes in blends.