Carbonization of eucalyptus wood and characterization of the properties of chars for application in metallurgy

Abstract

In view of the prominent energy & environmental problems associated with the use of fossil fuels, an increasing attention is now being paid by the metallurgists for the alternate energy sources which are renewable and environment friendly in nature. Biomass (i.e. wood) obtained by fast growing trees appears to be highly beneficial and found suitable for plantations under Indian conditions. Charcoal obtained from these energy crops can be used as a reducing agent for iron-ore reduction. The aims of the present project work is i) Characterization of the properties of different components of eucalyptus tree, such as wood, bark, branch and leaves, and ii) Characterization of the physical and chemical properties of charcoals obtained at different carbonization conditions such as, temperature, heating rate and soaking time. It is found from the proximate analysis that the ash content of different components of eucalyptus wood is very low as compared to coal. It is also found that the calorific value of eucalyptus wood is higher than the other components of eucalyptus tree. The results shows that yield of char and their physical & chemical properties depends on the carbonization conditions, viz. temperature, heating rate and soaking time. The char yield decreases gradually with the increasing carbonization temperature and most of the volatilization occurs up to 800°C. The fixed carbon content increases while volatile matter decreases with increase in carbonization temperature. The calorific value of charcoals increases marginally with increase in carbonization temperature. Reactivity of Eucalyptus wood chars towards CO2 was measured and the effects of carbonization conditions were determined. It is found that the reactivity decreases with increasing carbonization temperature. Charcoals obtained under rapid carbonization were found to be more reactive than the chars obtained under slow carbonization.