Biocarvão de bagaço de cana-de-açúcar como condicionador de solos: produção e caracterização

• Ano de defesa: 2022
• Autor(a) principal: Silva, Antônio Givanilson Rodrigues da
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Capacidade de troca de cátions; Capacidade de retenção de água; Resíduo sólido orgânico; Pirólise
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/70972

The increasing production of organic solid waste is a complex problem that requires technically, environmentally, and legally viable alternatives. The production of soil conditioners from these residues is pointed out as a promising alternative. Biochar is a carbonaceous material obtained through pyrolysis of organic materials and which has greater water retention, nutrient availability, and recalcitrance than its feedstock, thus being a potential soil conditioner. Therefore, the purpose of this research was to develop a biochar from sugarcane bagasse, an abundant organic residue in Brazil, which is the world's largest sugarcane producer, and to investigate its potential for use as a soil conditioner, in relation to its physicochemical properties, and their compliance with the requirements of the Brazilian Ministry of Agriculture, Livestock and Supply (MAPA). Four biochars were produced, at temperatures of 350 ºC, 450 ºC, 550 ºC and 650 ºC, to find the one in which the biochar presented the best characteristics for use as a conditioner. The physicochemical characterization of the organic residue and the resulting biochars was carried out, using analysis of pH, EC, apparent density, Cation Exchange Capacity (CEC), Water Holding Capacity (WHC) and contaminants, according to the official analytical methods for soil conditioners, in addition to Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) analyses. The results obtained were compared with the MAPA requirements regarding CEC (200.00 mmolc kg-1 ), WHC (60%), and contaminant limits. Biochar obtained at 550 ºC was the only material that simultaneously satisfied all criteria, with CEC (282.22 mmolc kg-1 ) and WHC (68%) above regulatory limits, and contaminants below. The SEM, XRD and FTIR analyses corroborated the indication of this material as the one with the greatest potential for use as a soil conditioner, presenting greater specific surface, recalcitrance, and balance of oxygenated and aromatic functional groups, justifying both the higher values of CEC and WHC. Thus, it can be considered that the production of biochar from sugarcane bagasse for use as a soil conditioner is a potential and strategic alternative for the organic waste management