Clarifying the carbonization temperature effects on the production and apparent density of charcoal derived from Amazonia wood wastes

Abstract

Controlling the carbonization process in brick kilns based on temperature and selecting raw material to reduce heterogeneity are key challenges in producing high-quality charcoal from Amazonia wood wastes. The study's main objective was to investigate how the final carbonization temperature and different Amazonian wood species affect the carbonization efficiency and the charcoal apparent density (CAD). After determining wood basic density (WBD), the wastes underwent carbonization on a laboratory scale at four final temperatures (400, 500, 600, and 700 °C). The gravimetric yield in charcoal (GYC), the specific consumption of firewood (SCF), and the CAD were evaluated. The CAD ranged from 0.248 (T. guianensis) to 0.656 g cm−3 (Licania sp.) and showed a positive correlation with WBD at all temperatures (400 °C - r = 0.954, 500 °C - r = 0.944, 600 °C - r = 0.930, and 700 °C - r = 0.927). Wastes from the species P. suaveolens and D. excelsa showed the highest mean values of GYC regardless of the carbonization temperature. The increase in the final carbonization temperature from 400° to 700°C reduced the GYC and increased the SCF and CAD. The species T. guianensis (25.6%), Manilkara sp. (25.4%), and D. excelsa (24.7%) showed more significant reductions in GYC from 400° to 700°C. Thus, temperatures below 500 °C are recommended for charcoal production from Amazonia wood wastes to provide better carbonization performance. In our study, charcoals from Licania sp., D. excelsa, and Manilkara sp. were the densest and, therefore, most suitable for the steel industry.