Curva de secagem natural em toras de Eucalyptus urophylla sob condições locais do município de Apodi-RN

Abstract

Firewood is a material used on a large scale for the sintering of red ceramics in different regions of Brazil, however, it is necessary to consider the moisture content and the possible need for an investment in the previous drying process to obtain a greater balance. energy at the end of the energy production process. Natural drying is one of the options and, as it is economically viable when compared to artificial drying, depending on the climatic conditions of the region in which it is carried out, it brings economic gains that can be significant for the company. In this context, the objective of this work was to characterize the natural drying curves, in four different diameter classes, using pieces of Eucalyptus urophylla wood, under the climatic conditions of the municipality of Apodi RN. The material came from a clonal plantation installed at Escola Agrícola de Jundiaí in Macaíba RN as part of an international project in partnership with IPEF (Instituto de Pesquisas Florestais) with material at 6 years of age. The experiment was set up in a pottery industry in Apodi RN. Initially, 85 trees were selected, and 100 pieces of wood were sectioned from these, with a fixed length of one meter, and four different diameter classes, named: Class 1: 6 to 8 cm, Class 2: 10 to 12 cm, Class 3: 14 to 16 cm and Class 4: 18 to 20 cm. These were transferred to the municipality of Apodi RN 7 days after slaughter, where the masses (Kg) of each of the samples were periodically measured for 220 days, with average intervals of one month, to monitor the mass loss and subsequent characterization. of the drying curves. For data interpretation, quantitative descriptive statistics were applied, obtaining the mean, the coefficient of variation (CV) and the standard deviation. To verify the distribution of data, a regression analysis was performed for each diameter class and an analysis of variance was performed to compare the means between classes, being: p>0.05 significant and p<0.05 non significant. It was concluded that for the pieces within Class 1 (6 8 cm) the mass loss was greater, with a lower moisture content than the others (45.9%) and a higher drying rate (1.2%) at 36 days, approaching the ideal value for the best energy balance, which is around 25 to 35%. There was a drying curve with significant losses until the 36th day with subsequent stabilization of the values. It is recommended to use class 1 pieces from the thirty sixth day for the conditions of the municipality of Apodi RN no, since the results showed that it will no longer dry significantly. Statistical analyzes related to moisture loss resulted in a higher average for class 2 (59.63). The CV was classified as homogeneous for all classes. Complementary studies are suggested, under the same conditions, so that the presence of the peel in the pieces is evaluated.