Abstract: The use of wood as a bioenergetic source requires knowledge of its technical properties. The rubber tree Hevea brasiliensis has an economic life cycle of 25 to 30 years in Brazil. It is used for extracting rubber and generating residual wood for fuel. Our goal was to characterize the wood quality of 10 clonal progenies as a source of raw material for bioenergy. Ten clonal progenies of 12-year-old Hevea brasiliensis from an experimental planting in Selvíria municipality were evaluated. Three trees per clone were evaluated for individual properties of Higher Heating Value, immediate chemical analysis, chemical composition, fiber dimensions, thermogravimetric analysis of wood under nitrogen atmosphere and Fourier Transform Infrared Spectroscopy analysis. We highlight clone IAC 311 for fuel because it presents elevated Higher Heating Value and fixed carbon and less volatile material. However, the other genetic materials studied also meet the specifications for energy use and can be highly viable given their physical, chemical, energy, and thermal properties.

Charcoal has a large share in the Brazilian market. The production is carried out by pyrolysis of biomass at different temperatures, between 300 and 500 °C. In this study, the corn cob pyrolysis was investigated using thermogravimetric analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). Samples after pyrolysis were compared with raw biomass to evaluate changes in fuel characteristics. In DTG curves a reduction in the number of degradation peaks in the carbonized material was observed. The FTIR spectra allowed to identify the aromatic ring of the lignin in the charcoals structure, indicating the presence of this compound even in charcoals produced with a temperature of 500 °C. It can be concluded that the temperature of 400 °C was enough to completely degrade the hemicellulose and cellulose of the biomass, resulting the final product (charcoal) less reactive or thermally more resistant than the in natura corn cob.

ABSTRACT The aim of this study was to apply geostatistics to predict the spatial pattern of variations in moisture content of eucalyptus wood chip piles to generate subsidies for adequate sampling and material handling. Wood chip piles were installed in three different storage cycles using newly cut material for 7, 30, and 60 days. Sampling was performed in axial (top, middle, and base) and lateral positions, so that all samples were georeferenced in relation to the distance from the ground and the center of the pile. Moisture values were submitted to geostatistical analysis and kriging. The results confirmed the spatial dependence of moisture content over the piles stored at 7 and 30 days; however, the effect of rainfall was crucial to reduce the spatial dependence of moisture content. The results showed that geostatistics is a useful tool for the creation of reliable sampling protocols.

ABSTRACT This work aims at the physicochemical characterization of four species: Eucalyptus sp, Pinus sp, Citrus sinensis and Hevea brasiliensis for use in ceramic furnace. Immediate analysis, chemical analyses were carried out (total extractives, Klason lignin, holocellulose and alpha-cellulose content). Results were applied to ANOVA and Tukey for statistics. The ash content of Pinus sp was 1.60%, for volatile material content Eucalyptus sp presented 83.61%, for fixed carbon values, Citrus sinensis presented 20.03%. Chemical analyses in the total extractive content, Citrus sinensis presented 21.76%, Klason lignin content, Pinus sp had 39.24%, Eucalyptus sp 60.29% had the highest holocellulose and alpha-cellulose, which was 42.72%. Pinus sp sample was the one with the highest heating value of 20.090 J/g. According to results obtained in the analyses, it is possible to conclude that all species have potential for applications in ceramic furnace.

Eucalyptus bark is a waste generated in large volume and has been used as a source of energy. This study tries to use the Eucalyptus sp. bark as a source of raw material for the charcoal production and to study the influence of pyrolysis temperatures on charcoal properties. Charcoal was produced at different temperatures: 300, 400 and 500 °C, and their properties were determined by proximate analysis, higher heating value and thermogravimetric analysis. It was observed that higher pyrolysis temperature resulted in increase of the fixed carbon content and higher heating value. In the thermogravimetry and derivative thermogravimetry curves it was possible to determine the differences in the thermal stability of charcoal produced. It can be concluded that the eucalyptus bark charcoal is an alternative for the energy reutilization of this waste and also can be used as charcoal for heating.

RESUMO Uma alternativa como fonte para geração de energia é o uso de biocombustível sólido produzido pelo processo de briquetagem. O briquete é produzido pela compactação de materiais lignocelulósicos, possibilitando que haja maior energia em menor volume. O objetivo desse trabalho foi analisar a briquetagem do Schizolobium parahyba (guapuruvu), avaliando-se a estabilidade, densidade, resistência mecânica e friabilidade dos briquetes. Foram testados três granulometrias diferentes: tratamentos T1 (maior que 40 mesh), T2 (entre 40 e 60 mesh) e T3 (menor que 60 mesh), todos briquetados a um teor de umidade de 12%, utilizando-se prensa hidráulica sem o uso de aquecimento nem aglutinante. Os três tratamentos diferiram significativamente entre si quanto à densidade, expansão longitudinal e resistência à tração por compressão diametral. A granulometria mais fina (T3) apresentou os melhores resultados para todos os parâmetros, tendo os maiores valores para a densidade (0,932 g.cm-3) e resistência (0,485 MPa) e menor índice de friabilidade (8,35%). Os resultados mostraram que a granulometria interfere nas características do produto final. O estudo mostrou que o guapuruvu pode ser uma alternativa para a produção de biocombustível sólido.

ABSTRACT The use of solid biofuel produced by the briquetting process is an alternative source for power generation. The briquette is produced by the compression of lignocellulosic materials, allowing for a higher energy at a lower volume. This work aimed to study the briquetting process of Schizolobium parahyba (guapuruvu). It was evaluated the stability, density, mechanical resistance and friability of the briquettes. The treatments were: T1 (above 40 mesh), T2 (between 40 and 60 mesh) and T3 (below 60 mesh). All treatments were adjusted to a moisture content of 12%. The briquettes were produced by hydraulic press without using heat or binder. The three treatments were statistically different from each other in terms of density, height expansion and diametrical compression resistance. The treatment T3 showed the best results for all parameters, with the highest values for density (0.932 g.cm-3) and mechanical resistance (0.485 MPa). Also, T3 presented the lowest friability (8.35%). The results showed that the particle size interferes in the final product characteristics. The study showed that guapuruvu could be an alternative for solid biofuel production.

O presente trabalho teve como objetivo avaliar o efeito da granulometria da biomassa residual da madeira de Pinus sp. na qualidade de briquetes. A biomassa residual utilizada foi obtida do processo industrial de processamento da madeira de Pinus sp., sendo classificada em (i) serragem; material residual do processo industrial apresentando granulometria diversa e (ii) moída; material moído e classificado na peneira de 60 mesh. Da biomassa foram determinados os teores de materiais voláteis, cinzas e carbono fixo, poder calorífico superior, densidade a granel e energética e produzidos briquetes em briquetadeira laboratorial com temperatura de 120ºC, tempo de prensagem de 5 minutos, pressão de 140 kgf.cm-2 e tempo de resfriamento de 10 minutos. A qualidade dos briquetes foi determinada pelas variáveis energéticas e físico-mecânicas: densidade aparente e energética, durabilidade, resistência à tração por compressão diametral e expansão volumétrica. Os resíduos de biomassa de Pinus sp. provenientes do processamento da madeira são adequados para a confecção de briquetes. Não houve efeito significativo da granulometria da biomassa de Pinus sp. nas características energéticas e físico-mecânicas dos briquetes. A utilização da biomassa residual obtida diretamente do processamento da madeira de Pinus sp. é recomendada para produção de briquetes em detrimento a biomassa mais fina, com 60 mesh, pois a ela estão atrelados menores custos de produção, sem a necessidade de reprocessamento da matéria-prima e adequação granulométrica.

The present work aims to evaluate the effect of the biomass granulometry of Pinus sp. on the quality of briquettes. The residual biomass used was obtained from the industrial processing of Pinus sp. wood, being classified in (i) sawdust; residual material of the industrial process presenting diverse granulometry and (ii) ground; material graded and classified in 60 mesh sieve. The proximate analysis (volatile, ash and fixed carbon contents), highest calorific value, bulk and energy density of the biomass was determined and produced briquettes with temperature of 120ºC, pressing time of 5 minutes at a pressure of 140 kgf.cm-2 and cooling time of 10 minutes. The quality of briquettes was determined by the energy and physical-mechanical variables: bulk and energetic density, durability, tensile strength by diametrical compression and expansion. The residues of Pinus sp. are suitable for the production of briquettes. There was no effect of biomass granulometry in the energetic and physico-mechanical characteristics of briquettes. The use of residual biomass obtained directly from the processing of Pinus sp. is recommended for the production of briquettes in detriment to the finer biomass with 60 mesh, because it is linked to lower production costs

RESUMO Os sistemas florestais de curta rotação possuem elevada produtividade em reduzido espaço de tempo e área, entretanto poucos trabalhos enfocam a qualidade da biomassa florestal produzida nessas condições. De fato, a qualidade da matéria-prima é muito importante para alto rendimento nos sistemas energéticos. Dessa forma, este trabalho teve como objetivo estudar a madeira com casca proveniente de diferentes sistemas florestais adensados, por meio do conhecimento do poder calorífico superior e dos principais componentes químicos da madeira – lignina insolúvel, extrativos e cinzas. Adicionalmente, estudou-se o acúmulo desses componentes por árvore ao longo do tempo. As florestas clonais de Eucalyptus urophylla x Eucalyptus grandisforam plantadas em cinco espaçamentos de plantio e três níveis de adubação. Aos 18, 24 e 30 meses após o plantio, coletaram-se árvores-amostra, das quais foram separados discos da região do DAP para análises químicas. No geral, os teores de lignina insolúvel, extrativos totais e cinzas obtidos nos diferentes tratamentos estão de acordo com os encontrados na literatura e assemelham-se aos das árvores mais velhas da mesma espécie. O acúmulo dos componentes químicos por árvore foi maior em florestas menos adensadas (espaçamentos mais amplos).

ABSTRACT The short rotation forestry systems have high productivity in short period of time and area, however, few studies focused on the quality of forest biomass produced in these conditions. In fact, the quality of the raw material is very important for high performance of energy systems. Thus, the present work aimed to study the wood with bark from different dense forest systems, through knowledge of the gross calorific value and the main chemical components of wood – insoluble lignin, extractives and ash. Additionally, we studied the accumulation of these components in the tree over time. Clonal forestry ofEucalyptus urophylla x Eucalyptus grandis were planted in five planting spaces and three fertilization levels. At 18, 24 and 30 months after planting, sample trees was collected and disks from the DBH region were separated for the chemical analyses. Overall, the levels of insoluble lignin, extractives and ash obtained from the different treatments are in agreement with the literature and the values are similar with other older trees from the same species. The accumulation of chemical components in each tree was higher in less dense forests (more space between trees).

RESUMO Este trabalho teve por objetivo avaliar briquetes produzidos a partir de finos de carvão vegetal compactados com resíduo celulósico gerado na decantação dos efluentes da indústria de papel e celulose. Foram realizados os seguintes tratamentos: briquetes produzidos com fino de carvão vegetal e resíduo celulósico nas proporções de 25% (T1), 30% (T2), 35% (T3), 40% (T4) e 45% (T5) e briquetes produzidos com finos de carvão vegetal com 10% de amido e resíduo celulósico nas proporções de 0% (T6), 5% (T7), 10% (T8), 15% (T9), 20% (T10) e 25% (T11). A caracterização dos briquetes foi realizada por meio de ensaios de análise química imediata, determinação do poder calorífico superior, densidade aparente e avaliação da resistência mecânica após a secagem dos briquetes em estufa ou ao ar livre. Observou-se que os briquetes com resíduo celulósico e amido em sua composição apresentaram maior densidade e resistência mecânica à compressão, concluindo-se, assim, que a presença do amido favoreceu a compactação e estabilidade dos briquetes. Observou-se, também, que o processo de secagem em estufa prejudicou a qualidade dos briquetes, de modo que a secagem ao ar livre forneceu briquetes mais resistentes e estáveis.

ABSTRACT This study aimed to evaluate briquettes produced from charcoal fines compressed with cellulosic residue generated in settling of the effluents from pulp and paper industry. The following treatments were performed: briquettes produced with charcoal fines and cellulosic residue in a ratio of 25% (T1), 30% (T2), 35% (T3), 40% (T4), 45% (T5) and briquettes produced with charcoal fines, 10% starch and cellulosic residue in a ratio of 0% (T6), 5% (T7), 10% (T8), 15% (T9), 20% (T10) and 25% (T11). Briquettes characterization was performed using immediate chemical analyses, determination of gross calorific value, apparent density and evaluation of their mechanical resistance after drying the briquettes in a kiln or outdoors. It was observed that briquettes with cellulosic residue and starch in their composition showed higher density and mechanical resistance to compression, thus concluding that the presence of starch favors briquettes compression and stability. It was also observed that the drying process in a kiln impaired the quality of the briquettes, so that the drying process outdoors resulted in more stable and resistant briquettes.

Pectin and starch are edible, non-toxic, biodegradable and obtained from renewable sources. Also, have the benefit to be easily cross-linked producing hydrogels. Reactive extrusion with edible citric acid and cross linking interactions was evaluated on extruded thermoplastic in natura and cationic starch-pectin blends. Materials water susceptibility and mechanical properties were characterised. Reactive extrusion decreased (up to 75% in natura starch) mechanical properties. Also have decreased (up to 32.4%) both starch polymers water absorption, indicating the possibility of increasing materials water barrier properties but had the opposite effect on the pectin-TPS material, probably related to a cationic-anionic cross linking, resulting in a hydrogel polymer. Reactive extrusion also have negatively affected mechanical properties of both starch polymers, however increased pectin-TPS blends stress and strain at rupture.

Este trabalho envolveu a moldagem de briquetes com utilização de resíduos de pó borra de café e serragem de madeira de eucalipto. Os briquetes produzidos a partir de biomassa vegetal podem ser aplicados como substituintes de outros combustíveis utilizados em caldeiras de processos industriais ou até mesmo para aquecimento de residências, em regiões frias, com utilização de equipamentos mais simples. No Brasil e em muitos países uma grande quantidade de resíduos de borra de café é produzida e desperdiçada no cotidiano e em indústrias de café solúvel. A serragem de madeira também é um resíduo bastante comum no Brasil, principalmente, em algumas cidades que concentram grande número de empresas que processam madeira. Assim, a moldagem de briquetes com estes resíduos sólidos é uma oportunidade de reaproveitar os resíduos para produzir um tipo de combustível proveniente de fonte renovável, contemplando também aspectos relacionados à bioenergia e Produção Mais Limpa (P+L). Desta forma, no presente trabalho foram realizadas moldagens de briquetes utilizando o pó da borra de café e serragem de madeira em diferentes proporções destes materiais para avaliar propriedades mecânicas de compressão diametral. Também foram realizadas análises para determinar os teores de umidade, voláteis e cinzas, além da determinação do poder calorífico superior (PCS). Todas as composições de briquetes contendo serragem ocasionaram acréscimos nos valores das médias das propriedades de resistência máxima à compressão diametral e módulo de elasticidade, quando comparados aos valores destas propriedades dos briquetes moldados apenas com a borra de café. As diferentes composições de briquetes contendo serragem apresentaram valores próximos de resistência à compressão diametral. Considerando os valores do poder calorífico (PCS), todas as amostras apresentaram resultados semelhantes em comparação com a literatura. Os briquetes contendo somente borra de café na composição apresentaram resultados de teores de cinzas, voláteis e PCS similares aos das amostras contendo serragem. Porém, os briquetes contendo somente borra de café apresentaram valores inferiores de resistência máxima à compressão quando comparados a todos os outros briquetes moldados também com serragem.

This work involved the molding briquettes with use of powder of coffee and eucalyptus wood sawdust residues. The briquettes produced from biomass can be applied as replacements for other fuels used in boilers for industrial processes or even for heating home in cold regions, using simple equipment. In Brazil and in many countries a large amount of waste coffee grounds is produced and wasted in daily life and in soluble coffee industry. The wood sawdust is also a fairly common residue in Brazil, especially in some cities that concentrate large number of companies that process wood. Then the molding of briquettes with these solid wastes is an opportunity to reuse the waste to produce a type of fuel from renewable sources, also including aspects related to bioenergy and Cleaner Production. Thus, in the present study were molded briquettes using the powder of coffee grounds and wood sawdust in different proportions of these materials to evaluate mechanical properties of diametrical compression. Also analyzes were performed to determine the moisture, volatile matter and ash contents, besides the determination of the calorific value content (PCS). All compositions containing sawdust briquettes caused increases in mean values of maximum resistance properties diametrical compression and elastic modulus when compared to the values of these properties of briquettes molded only with the coffee grounds. The different composition of briquettes containing sawdust presented similar value of resistance to diametrical compression. Considering the calorific values (PCS), all samples showed similar results compared to the literature. The briquettes containing only coffee grounds in the composition presents results of ash, volatile contents and PCS similar to the samples containing sawdust. However, the briquettes containing only coffee grounds showed lower maximum compressive strength compared to all other also molded with sawdust briquettes.

O conhecimento das variações das características da madeira produzida pelas árvores de eucalipto em função da idade e posição no tronco é fundamental para o seu uso adequado. O presente trabalho teve como objetivo avaliar a influência da idade e das posições longitudinal na densidade básica e radial nas características anatômicas do lenho das árvores de Eucalyptus grandis plantadas no espaçamento 3x2 m e fertilizadas com adubação comercial no plantio, 6º, 12° mês. Foram selecionadas, de acordo com a distribuição de área basal, quinze árvores de eucalipto com 24, 36 e 72 meses de idade, sendo 5 árvores/idade, e cortados discos do lenho a 1,30 m da altura do solo (DAP) para as determinações das dimensões das fibras (comprimento, espessura da parede, diâmetro do lume e largura total) e vasos (diâmetro tangencial, frequência e área ocupada) e em diferentes alturas fixas do tronco para a determinação da densidade básica. A densidade básica do lenho aumentou de 0,43 g.cm-3 para 0,46 g.cm-3 com o avanço da idade das árvores, apresentando um modelo de variação longitudinal, comum as três idades, caracterizado pelo decréscimo da base-3m (0,42-0,49 g.cm-3 0,40-0,46 g.cm-3) e posterior aumento até a extremidade (0,46 g.cm-3 0,54 g.cm-3) do tronco. As dimensões das fibras e dos vasos apresentaram variações tanto em relação à idade quanto no sentido medula-casca. O comportamento e as variações das características do lenho das árvores de eucalipto indicam que o meristema cambial está formando, até este período, o lenho denominado de juvenil.

The knowledge of the variations in the wood characteristics produced by eucalyptus trees according to age and sampling positions is essential for its proper use. This study had as objective to evaluate the influence of the age, longitudinal and radial positions on basic density and anatomical characteristics in Eucalyptus grandis wood. The trees were planted in 3x2 m spacing and fertilized with commercial fertilizers in planting, 6th and 12th months. According to basal area distribution, fifteen trees were selected (24, 36 and 72 months of age) - five trees per age. Disks at DBH position (1.3 m) were taken for fiber determination (length, wall thickness, lumen diameter and width) and vessels (tangential diameter, frequency and area occupied) and in other different sampling positions for basic density determination. Wood basic density increased from 0.43 to 0.46 g.cm-3 as well as the trees age increases with a longitudinal variation model, characterized through a decrease in base-3m (0.42-0.49 0.40-0.46 g.cm-3) and an increase to the top of the trunk (0.46 0.54 g.cm-3) Fibers and vessels dimensions showed variations related to age and to pit-bark direction. Wood properties behavior and variations indicate that, until this period, the juvenile wood is being formed.

O conhecimento da capacidade produtiva e das variáveis que interferem no rendimento das máquinas é fundamental para a otimização das operações na colheita florestal. O objetivo deste trabalho foi avaliar o desempenho operacional e a eficiência de máquinas Harvester e Forwarder, utilizadas na exploração florestal, no sul da Bahia. Foram utilizados dados do número de horas programadas e efetivas de trabalho das máquinas e motivos de paradas, obtidos de arquivos históricos, de outubro/2010 a setembro/2011. Com base nestes dados, foram calculadas as horas totais de trabalho, eficiência operacional e disponibilidade mecânica das máquinas. As máquinas Harvester apresentaram média de horas totais de trabalho de 480 horas e 18 minutos, sendo 75,6% (363,2 horas) de horas efetivas e 24,4% (117,1 horas) de horas paradas. As máquinas Forwarder apresentaram média de horas totais de trabalho de 481 horas e 36 minutos, sendo 84,7% (407,9 horas) de horas efetivas e 15,3% (73,7 horas) de horas paradas. A eficiência operacional média foi de 73,2%, para a Harvester, e de 82,2%, para a Forwarder, sendo que as paradas técnicas, como deslocamentos e manutenções preventivas e corretivas, foram as principais causas de influência nestes valores. O desempenho operacional das máquinas mostrou-se adequado, em função da distribuição dos tempos, com 76% e 85% de tempo efetivo de trabalho, para a Harvester e Forwarder, respectivamente, e média de 89% para disponibilidade mecânica, para ambas as máquinas, as quais apresentaram eficiência operacional satisfatória (acima de 70%).

The knowledge on productive capacity and variable elements that affect machines efficiency is essential for optimizing operations in forest harvesting. This study aimed to evaluate Harvester and Forwarder machines efficiency and operational performance, for forest exploitation, in the south of the Bahia State, Brazil. Data concerning the number of programmed and effective working hours, as well as reasons for machine downtime, were collected from historical archives, from October 2010 to September 2011. Based on these data, the total working hours, operational efficiency, and mechanical availability were calculated. Harvester machines showed an average of total working hours of 480 hours and 18 minutes, being 75.6% (363.2 hours) of effective work and 24.4% (117.1 hours) of downtime. Forwarder machines showed an average of total working hours of 481 hours and 36 minutes, being 84.7% (407.9 hours) of effective work and 15.3% (73.7 hours) of downtime. The average operational efficiency was of 73.2%, for the Harvester, and 82.2%, for the Forwarder, and technical downtimes, such as displacements and corrective and preventive maintenances, comprised the main reason for explaining those values. The machines operational performance showed to be adequate, according to time distribution, with 76% and 85% of effective working time, respectively for the Harvester and Forwarder, and an average of 89% for mechanical availability, for both machines, which showed satisfactory operational efficiency (above 70%).