The anatomy of wood and charcoal was analyzed by scanning electron microscopy in three radial positions of E. urophylla and E. Grandis in different diameter classes at six years. The carbonization process was given in the muffle with an average rate of 0.5 °C increment per minute, using initial temperature of 150 °C and maximum of 450 °C. It was observed that the pore diameter presented higher values in the samples obtained in the internal position. The diameter classes of the trees almost did not influence the characteristics of the fibers. In the external position (close to the shell) fibers with higher values of cell wall thickness and smaller values of lumen diameter and width were identified. The fiber lumen diameter was not affected by the wood carbonization process, whereas the cell wall thickness and fiber width were reduced.
Brazil is the world’s largest producer of charcoal. Therefore, there is need for improvement in the gravimetric yield of conversion and the reduction of gas emissions, including greenhouse gases (GHGs), released during carbonization. The objective was to apply the methodology of Measurement, Reporting and Verification (MRV) to evaluate the emission of GHG, mainly CO2 and CH4. The charcoal production kiln-furnace system used was composed of 4 kilns with a capacity of ~6 t of wood, each. The MRV cluster of coal gravimetric yield and gas burners were used to determine the gravimetric yield and burner efficiency and thus evaluate the emission of GHGs generated in the carbonization system. The carbonization was performed in an isolated way producing, in total, 3.34 t of charcoal, with an average gravimetric yield of 25.82%. The MRV methodology was effective for evaluating the GHG emissions. The wood burner reduced by 50% the methane burning and provided a reduction of 0.392 tCO2 eq (23.91%). The humidity of wood and high precipitation were the main limiting factors in this research, and responsible for the decrease in the gravimetric yield. The kiln-furnace system was effective for a sustainable production with the use of non-continuous carbonization gas burners.
Considering the extraordinary diversity of the Brazilian Cerrado and the difficulties related to the inspection of environmental crimes, knowing the wood and charcoal anatomy of widely exploited species is important. Thus, this study aimed to verify the anatomical characteristics of the wood and charcoal of Sclerolobium paniculatum. Therefore, anatomical characterizations of the wood and the charcoal produced were performed in order to compare the characteristics of both materials and observe any possible changes in the anatomical properties after carbonization. The results exposed that the qualitative anatomical characteristics of S. paniculatum wood can be maintained after the carbonization process. However, quantitatively, the carbonization increased the vessel frequency value and height and width of rays, despite reducing the frequency of rays. The diameter of the vessels was not altered by carbonization. This characterization of the species can then serve as a database for future identification of charcoal produced with this wood. In addition, it can encourage increasing the quality of inspection and consequently reducing the illegal exploitation of the species in natural environments.
3 May 2011 in Journal of Biotechnology and Biodiversity
O trabalho teve como objetivo realizar a quantificação e qualificação energética da maravalha gerada em uma serraria do município de Jerônimo Monteiro/ES, esse material foi composto por uma mescla de diversas madeiras. Foram realizadas visitas técnicas na serraria duas vezes por mês com intuito da realização da análise quantitativa, e para a coleta de três amostras para a realização das análises de umidade, densidade a granel, análise química, teor de cinzas, análise elementar e o poder calorífico. Concluiu-se que a densidade a granel da maravalha analisada é apropriada para produção de briquete, verificou-se que este resíduo é adequado para a produção de energia.
There is a lack of techniques for the rapid and accurate determination of wood quality for charcoal production with good energy characteristics. The association of NIR spectroscopy and important charcoal parameters allows the prediction of these characteristics. This is a fast method that does not require sample preparation before the reading. The spectral readings were performed with solid and ground samples, and presented the second best representation of the evaluated parameters. Data went was adjusted to correct for variations that could occur during the spectra reading. The treatment with the best results was the normal transformation of variation. The evaluated spectra were able to explain 77% of the data for the variable gravimetric yield, 88% for volatile materials content and 86% for fixed carbon content.