Caracterização nutricional do extrato ácido proveniente da carbonização de madeira cambará (Qualea sp.) para uso agronômico

Abstract

During the wood carbonization process – in this case, from the specie Qualea sp. (Cambará), the coal is the main output product, other secondary products are the bio-oil and acid extract (AE) generated from the condensable gases released during the pyrolysis, as well as the non condensable gases CH4, CO, CO2 e H2. For a long time AE already has its economic function, however its use remains unusual. As the environmental issues are raising and, consequently, the interesst on reusing industry waste in several ways, the collected volume of AE in Brazil is still very low, corresponding to less than 1% of the total produced by the brazilian coal industry. This product already has several defined destinations with comproved actions, as its use for soil tamponade, stabilizing the pH and helping on phospor absorption; its addition of up to 1% on animal nutrition, providing a better nutrient assimilation due to a raise on the animal’s intestinal flora; on the dilution of chemical defensives without losing its efficiency; as relepent of some kinds of pests as well as preventing diseases; it can be powdered above the aerial plant parts, stimulating it, making it more lush, improving the product quality and others. Studies about the AE mineralization, as well as studies about its toxicology are important to evaluate the environmental impacts of this products on the soil. Physical, chemical and nutritional analysis were conducted upon the AE generated from the Qualea sp. (Cambará) carbonization to characterize it in relation to the availability of nutrients to the soil microbiota and the plants, as its contribution to the raise of organic matter on the soil. In order to achieve that, were conducted acidity analysis, quantification of total, organic and inorganic carbon and inorganic elements Na, K, P, B, Zn, Cu, Mg, Mn e Ca. In general, the Qualea sp. AE presented a buffering effect on its pH curve, probably due to its majority concentration of acetic acid. On the chemical elements quantitative analysis were observed 277,23 mg. ℓ-1 of carbon as well as consistent concentrations of P, K, Mn and CA, showing itself as a nutriente and carbon source for the soil and, consequently, for the plant.