Relationships between soil properties and species establishment in the restoration of mined soils in the cerrado biome

Restoring the ecosystems of the Cerrado biome is challenging considering the diversity of phytophysiognomies present in the biome, some of which are composed of species from different strata (herbaceous, shrubby, and arboreal), which increases the complexity of restructuring the floristic composition. Other factors was involved, such as soil quality, which directly influences the success of restoration, water storage, and nutrients, the financial costs, and a slow ecological process, due to the adverse circumstances found in the area. be restored. The strong anthropogenic interventions by mining processes reduce dramatically the physical and nutritional composition of the soil. We studied two restoration areas in Paracatu, Brazil, to examine their edaphic conditions six years after mining activities ceased and relate them to the status of the restoration process. In 2009, a Cerrado restoration were established in an area previously explored for gravel extraction. Plants were sampled and identified in 11 transects along the planting lines. The diameter base (DB) and total height (HT) were measured. The physical/chemical quality of the soil substrate was determined using a collection of samples in open trenches at four types of points: Cerrado (TC); dead plant pits (TM); seedling pits having living individuals of the most abundant species (TT); and those of the second-most abundant species (TE). Cecropia pachystachya Trécul and Tapirira guianensis Aubl. were most abundant and demonstrated the potential to thrive in areas degraded by mining having low mortality rates and growth at relatively DB and HT. The physical quality indicators in the gravel pits were not limiting, indicating that substrate preparation was efficient in this regard. The organic matter content in TM, TT, and TE was low in comparison to that of TC, and the chemical conditions in the TE pit substrates were similar to those in TM pits, suggesting C. pachystachya is a species with good plasticity, whereas T. guianensis is present in pits with higher levels of phosphorus

CARACTERIZAÇÃO DO RESÍDUO DE MDF E SEU APROVEITAMENTO NA PRODUÇÃO DE PELLETS

O processamento dos painéis de MDF, para a fabricação de móveis, gera uma grande quantidade de resíduos que constituem passivo ambiental, podendo ser utilizados para geração de energia. O objetivo deste trabalho foi avaliar as características do resíduo de MDF e seu aproveitamento na produção de pellets, visando a aplicação energética. A caracterização energética do resíduo foi realizada por meio da química imediata (teores de cinzas, voláteis e carbono fixo) e do poder calorífico superior. Além disso, foram produzidos e avaliados pellets (características energéticas e físico-mecânicas). A avaliação das características do resíduo: poder calorífico superior (4427,8 kcal.kg-1) e química imediata (carbono fixo, materiais voláteis e cinzas foram 16,3; 82,3 e 1,4%, respectivamente) e dos pellets de MDF: densidade aparente (1,15 g.cm-3), a granel (0,61 g.cm-3), energética (2,6 a 5,5 Gcal.m-3) e durabilidade (99,87%) indicaram a viabilidade técnica do aproveitamento do material como fonte energética. As características energéticas e físico-mecânicas dos pellets de MDF atenderam as especificações de qualidade exigidas nas normas internacionais de comercialização, exceto para o diâmetro médio.Palavras-chave: materiais densificados, potencial energético, painéis. CHARACTERIZATION OF MDF RESIDUE AND ITS USE IN PELLET PRODUCTION ABSTRACT:The processing of MDF panels, for the manufacture of furniture, generates a large amount of residues that constitutes an environmental liability, and can be used for power generation. The objective of this work was to evaluate the characteristics of the MDF residue and its use in the production of pellets, aiming at the energetic application. The energetic characterization of the residue was carried out by means of the proximate analysis (ash, volatile and fixed carbon contents), calorific value. In addition, pellets were produced and evaluated (energy and physico-mechanical characteristics). The evaluation of the characteristics of the residue: high heating value  (4427.8 kcal kg-1) and proximate analysis (fixed carbon, volatile materials and ash were 16.3, 82.3 and 1.4%, respectively) and pellets: density (1.15 g cm -3), bulk density (0.61 g cm -3), energy density (2.6-5.5 Gcal m-3) and durability (99.87 %) indicated the technical feasibility of using the material as an energy source. The energy and physical-mechanical characteristics of MDF pellets met the quality specifications required by international marketing standards, except for the average diameter.Keywords: densified materials, energetic potential, panels

CARACTERIZAÇÃO DO RESÍDUO DE MDF E SEU APROVEITAMENTO NA PRODUÇÃO DE PELLETS

O processamento dos painéis de MDF, para a fabricação de móveis, gera uma grande quantidade de resíduos que constituem passivo ambiental, podendo ser utilizados para geração de energia. O objetivo deste trabalho foi avaliar as características do resíduo de MDF e seu aproveitamento na produção de pellets, visando a aplicação energética. A caracterização energética do resíduo foi realizada por meio da química imediata (teores de cinzas, voláteis e carbono fixo) e do poder calorífico superior. Além disso, foram produzidos e avaliados pellets (características energéticas e físico-mecânicas). A avaliação das características do resíduo: poder calorífico superior (4427,8 kcal.kg-1) e química imediata (carbono fixo, materiais voláteis e cinzas foram 16,3; 82,3 e 1,4%, respectivamente) e dos pellets de MDF: densidade aparente (1,15 g.cm-3), a granel (0,61 g.cm-3), energética (2,6 a 5,5 Gcal.m-3) e durabilidade (99,87%) indicaram a viabilidade técnica do aproveitamento do material como fonte energética. As características energéticas e físico-mecânicas dos pellets de MDF atenderam as especificações de qualidade exigidas nas normas internacionais de comercialização, exceto para o diâmetro médio.Palavras-chave: materiais densificados, potencial energético, painéis. CHARACTERIZATION OF MDF RESIDUE AND ITS USE IN PELLET PRODUCTION ABSTRACT:The processing of MDF panels, for the manufacture of furniture, generates a large amount of residues that constitutes an environmental liability, and can be used for power generation. The objective of this work was to evaluate the characteristics of the MDF residue and its use in the production of pellets, aiming at the energetic application. The energetic characterization of the residue was carried out by means of the proximate analysis (ash, volatile and fixed carbon contents), calorific value. In addition, pellets were produced and evaluated (energy and physico-mechanical characteristics). The evaluation of the characteristics of the residue: high heating value  (4427.8 kcal kg-1) and proximate analysis (fixed carbon, volatile materials and ash were 16.3, 82.3 and 1.4%, respectively) and pellets: density (1.15 g cm -3), bulk density (0.61 g cm -3), energy density (2.6-5.5 Gcal m-3) and durability (99.87 %) indicated the technical feasibility of using the material as an energy source. The energy and physical-mechanical characteristics of MDF pellets met the quality specifications required by international marketing standards, except for the average diameter.Keywords: densified materials, energetic potential, panels