Investigating the pyrolysis temperature to define the use of charcoal

The production of charcoal for its many uses requires a careful selection of biomass and pyrolysis conditions, especially temperature, to ensure suitable quality. To do so, physical, chemical, and mechanical energy must be considered. This study aimed to analyze the yields and properties of charcoal produced at different pyrolysis temperatures. Eucalyptus saligna wood was pyrolyzed in a reactor with final temperatures of 450, 550, 650, 750, 850 and 950 °C. The yields of charcoal, pyroligneous liquid and non-condensable gases were determined. Mass loss was determined for each temperature. Charcoal analysis included the determination of the apparent density, proximate analysis, heating value, mechanical strength, X-ray images for the internal visualization of its structure and hygroscopicity test. Relevant charcoal properties for the steel industry and barbecue, such as density, mechanical strength, heating value and hygroscopicity, show variable trends from pyrolysis at 650 °C. The results show that pyrolysis temperature had a great impact on the properties of charcoal. The apparent density of charcoal rose from 500 °C and had no relation to the breaking strength. When the pyrolysis temperature was raised, an increase in both apparent and true densities, internal fissures and cracks and fixed carbon content of charcoal was observed.