Carvão de eucalyptus: efeito dos parâmetros da pirólise sobre a madeira e seus componentes químicos e predição da qualidade pela espectroscopia NIR

• Ano de defesa: 2008
• Autor(a) principal: Campos, Ana Carolina Maioli
• Orientador(a): Mori, Fábio Akira
• Banca de defesa: Trugilho, Paulo Fernando, Napoli, Alfredo, Mendes, Lourival Marin, Brito, José Otávio
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: UNIVERSIDADE FEDERAL DE LAVRAS
• Programa de Pós-Graduação: DCF - Programa de Pós-graduação
• País: BRASIL
• Palavras-chave em Português: Tecnologia e utilização de produtos florestais; Pirólise; Termogravimetria
• Área do conhecimento CNPq: CNPQ_NÃO_INFORMADO
• Link de acesso: https://repositorio.ufla.br/handle/1/2301

This study aimed at investigating the influence of the chemical characteristics of wood and parameters of process in the production of charcoal for steel, and proposing a technique for predicting the quality of coal on industrial scale. In order to accomplish this research, three interdependent studies were conducted in the department of Cirad-Persyst in Montpellier, France. Pressurized thermogravimetric analyses were performed in order to know the influence of pyrolysis parameters (temperature: 20°C -650°C; pressure: 0.1, 0.5, and 1 MPa, and heating rate: 5° C, 10°C and 20°C.min-1) on the thermal behavior of Eucalyptus wood and its models of chemical components (cellulose, xylan and lignin). The carbonization of grounded wood was performed for a population of 168 hybrids Eucalyptus urophylla x E. grandis, with 59 months of age, from which the following chemical characteristics were known: rates of extractives, Klason lignin, siringil, guaiacil and the sirigil/guaiacil ratio. The maximum carbonization temperature was 400 °C. The charcoal produced was analysed scanned in the near infrared region (NIR), using a spectrometer Bruker Vector 22/N. After obtaining the spectrum, the charcoal samples were submitted to chemical proximate analysis by the NBR standard 8112, where the volatile matter (TMV), ash (TCZ) and the fixed carbon content (TCF) were determined. The properties of the charcoal produced were correlated to those of wood and used for calibration of models PLS with the NIR spectra. Thermogravimetric results of lignin presented the greatest contribution in the formation of charcoal, followed by cellulose and xylan. The pyrolysis of cellulose was dependent on the pressure, possibly due to competitive reactions involved in its thermal degradation. The behavior was also observed for the wood, although it was less expressive. Lignin showed a negative trend concerning the increased pressure for the range investigated. The heating had a similar effect to the Eucalyptus wood and xylan. The properties of the charcoal produced from the hybrid Eucalyptus were consistent with the literature data, but it could not be verified high correlations between the chemical characteristics of wood and those of charcoal produced in the experimental conditions. The NIRS technique showed to be appropriated for the prediction of TMV and TCF of Eucalyptus charcoal. The models selected had prediction coefficients of 0.95 to TMV, and 0.96 for TCF, respectively.