Biocarbon pellets for steel production: Binder selection and pelletization challenges

Details

Supervisors

Jeanmart, Hervé

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil en génie de l'énergie , à finalité spécialisée

Abstract

enThe steel industry accounts for 8% of total energy system emissions, largely due to its reliance on fossil coke. Replacing coke with biocarbon pellets represents a promising decarbonization pathway. However, the low bulk density of biocarbons and the lack of natural binding components after high temperature pyrolysis make densification necessary. This thesis investigates the influence of different binders for the pelletization of Wood 1 biocarbon. Pelletization trials were conducted using a continuous KAHL pelletizer. Initial trials resulted in repeated die blockages due in part to insufficient moisture content. After adjusting conditions, four pellet types were produced, all exhibiting a bulk density more than four times higher than the raw material and a reduced reactivity toward CO2. The results showed the feasibility of pelletizing Wood 1 biocarbon. However, the increase of moisture and volatile contents dilutes the fixed carbon fraction. Upcoming work is needed to minimize binder and water addition to respect the metallurgical requirements. The present work highlights that moisture content and die geometry are the key parameters governing the pelletization. Next steps should focus on identifying their optimum combination. The limited availability of raw material prevented a comparison between the binders. Biocarbon pellets remain a promising pathway to reduce dependence on fossil coke, and the present results contribute to advancing this transition.