Estudo da decomposição térmica da madeira do cafeeiro / Study of the thermal decomposition of coffee wood

Considerando a necessidade de gestão adequada dos resíduos do cultivo e processamento do café, a energia presente na biomassa pode ser aproveitada através do processamento termoquímico do material para obtenção de produtos com maior valor energético ou matérias-primas químicas de valor agregado. Nesse sentido, o presente trabalho teve por objetivo estudar a decomposição termogravimétrica da madeira do cafeeiro em atmosferas inerte e oxidante, usando um DTG60H-SHIMADZU e aplicando as taxas de aquecimento de 10, 25 e 50 oC.min-1. A decomposição térmica da madeira do cafeeiro apresentou diferentes etapas: (I) em nitrogênio, foram secagem, pirolise ativa e carbonização; (II) em ar, foram secagem, pirólise ativa oxidativa e combustão do carvão formado na pirólise ativa oxidativa. Na análise em presença de ar, foi possível observar maiores taxas de reações, maior liberação de calor e baixa fração de material ao fim da análise. Os resultados obtidos contribuíram para uma melhor compreensão do comportamento de decomposição termoquímica da madeira do cafeeiro

Renewable energy potential and CO2 performance of main biomasses used in Brazil

This review investigates the effects of the Brazilian agriculture production and forestry sector on carbon dioxide (CO2) emissions. Residual biomasses produced mainly in the agro-industrial and forestry sector as well as fast-growing plants were studied. Possibilities to minimize sourcerelated emissions by sequestering part of carbon in soil and by producing biomass as a substitute for fossil fuel were extensively investigated. The lack of consistency among literature reports on residual biomass makes it difficult to compare CO2 emission reductions between studies and sectors. Data on chemical composition, heating value, proximate and ultimate analysis of the biomasses were collected. Then, the carbon sequestration potential of the biomasses as well as their usability in renewable energy practices were studied. Over 779.6 million tons of agricultural residues were generated in Brazil between 2021 and 2022. This implies a 12.1 million PJ energy potential, while 4.95 million tons of forestry residues was generated in 2019. An estimated carbon content of 276 Tg from these residues could lead to the production of approximately 1014.2 Tg of CO2. Brazilian biomasses, with a particular focus on agro-forest waste, can contribute to the development of sustainable alternative energy sources. Moreover, agro-waste can provide carbon credits for sustainable Brazilian agricultural development.Academy of Finland, AKA: 315019Academy of Finland [315019