Advanced Materials Letters

Abstract

The research presented in this publication focuses on the removal of phosphorus from basic oxygen furnace slags via the gas phase during carbo-thermal reduction in a bed of inductively heated graphite pieces. Its purpose is to evaluate the effect of the application of a novel reactor concept on the possibilities of phosphorus gasification. The slags are processed in two steps during the experimental trial: First, a silica source is added to reduce the basicity of the slag. In a second step, the actual reduction process is conducted at reaction temperatures of 1,623 K, 1,773 K and 1,923 K, respectively. The molten slag forms a film moving down the reactor with minimal contact time between iron (l) and phosphorus (g) so that a high amount of phosphorus gas can be removed from the reactor. The most important results are that more than 95% of the phosphorus contained in the slags could be reduced, roughly 85% of which were removed via the gas phase. Virtually iron-, chromium- and phosphorus-free slags are obtained. It is concluded that the application of the presented reactor concept based on thermodynamic evaluations potentially tackles the challenges posed by the reaction behaviour of phosphorus.