Quality and physicochemical characteristics of Eucalyptus charcoal produced at different ages and carbonization temperatures

Abstract

Brazil is a leader in global charcoal production. The Eucalyptus genus has good growth rates and wood properties, allowing the production of quality charcoal. However, characteristics such as age and carbonization temperature influence product quality. Thus, the aim of this study was to evaluate the influence of the wood age of a hybrid GG100 (Eucalyptus urophylla × Eucalyptus grandis) and carbonization temperature on charcoal quality. Trees were sampled at 12, 24 and 42 months of age. Carbonization was performed in an electric oven (furnace) at three carbonization temperatures to determine the influence of wood parameters (age, specific gravity, insoluble lignin, and extractive contents) and carbonization temperature on charcoal quality (gravimetric yield, immediate chemical composition, and apparent specific gravity). Overall, we observed differences in the yields of charcoal and pyroligneous liquid and in charcoal properties across ages and carbonization temperatures, as well as gas yield across the ages. In particular, wood age and insoluble lignin content were positively associated with fixed carbon content and negatively associated with pyroligneous liquid content. Additionally, the carbonization temperature was negatively associated with volatile matter content. According to standards, the charcoal produced from trees aged 24 and 42 months and at temperatures of 500 ºC and 550 °C, meets the requirements of the steel industry.

Keywords

• carbonization
• carbonization temperature
• gravimetric yield
• eucalyptus urograndis
• juvenile wood