Potential of charcoal from non-commercial corymbia and eucalyptus wood for use in the steel industry

Abstract

The search for species that produce high-quality charcoal is necessary to reduce the use of non-renewable sources of energy in the steel industry. Therefore, the present study aimed to evaluate the quality of new and non-commercial charcoal species in Brazil. Eight species of Corymbia and Eucalyptus were sampled and carbonized on a laboratory scale. The gravimetric yields of the carbonization, proximate and ultimate analysis, apparent density (AD) and energy density (ED), higher heating value (HHV), ignition (Di), and combustion (Si) indexes were determined through the curve of thermogravimetric derivative (DTG). The results suggest that C. variegata, E. longirostrata, E. major, C. henryi, and C. citriodora are competitively promising for producing charcoal for the steel industry when compared to the commercial species (E. urophylla) since they produce low reactivity charcoal (Si ∼3 × 107%2 min−2 °C−3), high energy density (>13 GJ m−3) and apparent density (>400 kg m−3). These characteristics are essential for a better energy performance, making the non-commercial species appropriate for use in Brazilian steel industry since there is a reduction on the energy consumption in the blast furnace per ton of iron produced.