Ailton Teixeira do Vale

Teor de umidade e densidade básica da madeira de nove espécies comerciais amazônicas

Este trabalho teve como objetivo agrupar especies com caracteristicas de teor de umidade e densidade basica da madeira semelhantes para compor cargas mistas de especies para secagem em câmaras industriais de secagem da madeira. Foram amostradas nove especies em floresta de terra firme na Amazonia Central com tres repeticoes por especie. Em todas as especies os teores de umidade nao diferiram entre base e topo do tronco, o que confere estabilidade da madeira durante o processo de secagem. Os valores de densidade basica variaram de 0,561 a 0,904 g cm-3. A partir do presente estudo foi possivel separar as especies em tres grupos com base na densidade basica e teor de umidade, o primeiro com as especies Minquartia guianensis, Lecythis poiteaui, Mezilaurus itauba, Manilkara huberi e Brosimum rubescens que sao consideradas madeiras pesadas (densidade variando de 0,835 a 0,904 g cm-3) , de secagem mais lenta ou dificil. O segundo grupo contem as especies Clarisia racemosa e Ocotea rubra (densidade media de 0,665 e 0,720 g cm-3, respectivamente) e o terceiro grupo com as especies Parkia paraensis e Brasimum parinarioides que apresentam densidade media e secagem rapida (densidade de 0,561 e 0,588 g cm-3, respectivamente).

POTENCIAL ENERGÉTICO DA BIOMASSA E CARVÃO VEGETAL DO EPICARPO E DA TORTA DE PINHÃO MANSO (Jatropha curcas)

In the production of biodiesel from Jatropha curcas, are produced residues in the peel and of pie form. One alternative use of these residues is in the energy production. The present work analyzed the energy potential of the peel and the pie of Jatropha curcas in the following conditions: in natura and charcoal, determining: the moisture content (VITAL, 1997); the ash, fi xed carbon and volatile matter (ABNT NBR 8112/86); the density and the gravimetric yield. The peel presented: moisture of 18,9%; density of 100kg/m3; volatile matter of 72,6%, fi xed carbon of 13% and 14,4% of ashes and heat combustion of 3.641kcal/kg. The carbonized peel produced 38.1% of charcoal, with: 29% of volatile matter, 45% of fi xed carbon and 25% of ashes; and heat combustion of 3.954kcal/kg. The pie presented: moisture of 2.41%, 601kg/m3 of density; volatile matter of 77.84%, fi xed carbon 14.21% and 7,95% ashes and 5.122kcal/kg of heat combustion. In the carbonization of the pie, 32% of charcoal was produced containing: 18.27% of volatile matter, 71.29% of fi xed carbon, 10.43% of ashes and heat combustion of 6.234kcal/kg. The high ashe contents are related to the fertilization of the plant.

Custo de produção das biomassas de eucalipto e capim-elefante para energia

Nesse estudo, objetivou-se estabelecer o custo de producao da unidade energetica gerada pela biomassa do eucalipto (Eucalyptus sp.), em diferentes tratamentos silviculturais, e pela biomassa do capim-elefante (Pennisetum sp.), e aplicar uma analise de sensibilidade para verificar as influencias de fatores como o tratamento silvicultural do eucalipto, a producao volumetrica de cada especie, o custo da terra e a taxa de juros nos custos de producao analisados. Foi demonstrado que o tratamento do eucalipto em plantio adensado e em curtissima rotacao de dois anos, com reforma do povoamento a cada seis anos, teve um custo medio de producao (CMPr) superior ao sistema convencional com rotacao a cada seis anos e reforma aos 18. Observou-se, tambem, que o eucalipto apresenta, em media, um CMPr de R

Is sewage sludge biochar capable of replacing inorganic fertilizers for corn production? Evidence from a two-year field experiment

4,41/Gj, inferior ao do capim-elefante, que, em media, e de R

Resistência natural de seis espécies de madeiras da região amazônica a fungos apodrecedores, em ensaios de laboratório.

5,44/Gj, mesmo com a capacidade que o ultimo tem de producao anual superior de materia seca. O capim-elefante tem a possibilidade de competir com o eucalipto quando um conjunto de condicoes se forma como taxa de juros igual ou superior a 8% a.a., preco da terra elevado e volume do capim-elefante igual ou acima de 35 toneladas de materia seca por hectare por ano.

Eficiência de um composto de iodo orgânico contra fungos apodrecedores de madeiras e térmitas.

ABSTRACT Sewage sludge (SS) is a by-product of wastewater treatment resulting from human and industrial activities. This waste is problematic because it is difficult to manage due to its volume and environmental impacts; therefore, new technologies for treatment are needed to make its final disposal feasible. Such technologies include the pyrolysis process that produces biochar, which can be used for agricultural purposes. The present study reports a two-year field experiment with SS biochar produced under different pyrolysis temperatures and its application to soil in combination with mineral fertilizer to evaluate its effect on soil chemical properties and on corn nutrition and yield. To conduct this evaluation, 15 Mg ha−1 of SS biochar combined or not with mineral fertilizer (NPK) was applied to the soil in the 2015 and 2016 cropping seasons. SS biochar increased soil chemical attributes, especially phosphorus, magnesium, cation exchange capacity and base saturation. Biochar resulted in a greater absorption of nutrients by plants and higher corn yields. However, SS biochar alone was incapable of increasing K uptake by corn. It was concluded that the application of SS biochar can replace mineral fertilizers (nitrogen, phosphorus and micronutrients) for corn production.

Influence of pyrolysis temperature on chemical and physical properties of biochar from sewage sludge

This study evaluated the natural resistance of six Amazonian wood species: Aspidosperma desmanthum (Araracanga) , Parinari excelsa (Parinari) , Mouriri callocarpa (Mirauba) , Marmaroxylon racemosum (Angelim-rajado) , Peltogyne paniculata (Roxinho) e Astronium sp. (Muiracatiara) against Pycnoporus sanguineous , a white rot fungus, and Gloeophyllum trabeum , a brown rot fungus. Testing was performed based on the American Society for Testing and Materials - Standard Method for Accelerated Laboratory Test of Natural Decay Resistance of Woods - ASTM D2017/81(86). Results showed that all tested wood species were classified as very resistant to both decay fungi, except the wood of Aspidosperma desmanthum , which demonstrated to be very resistant to Pycnoporus sanguineous and resistant to Gloeophyllum trabeum . The wood of Peltogyne paniculata showed the best performance against Pycnoporus sanguineous , whereas the wood of Astronium sp. presented the best results when submitted to Gloeophyllum trabeum attack.

Labile and stable pools of organic matter in soil amended with sewage sludge biochar

Species identification and their market value and price evolution since the colonization time of the remnants of the Brazilian Semi-Evergreen Forest (Floresta Estacional Decidual do Rio Uruguai) for potential timber production was assessed through 41 questionnaires, applied to timbermen and settlers from the surrounding region. The diversity of species for timber production commonly known by the people reached 63. From the 15 predominant species is relevant to mention Apuleia leiocarpa, Parapiptadenia rigida, Balfourodendron riedelianum, Nectandra megapotamica , Patagonula americana , Luehea divaricata, Cedrela fissilis, Ocotea diospyrifolia , Holocalyx balansae, Myrocarpus frondosus, Cabralea canjerana and Peltophorum dubium . The species with the highest commercial value were: Cordia trichotoma, Cedrela fissilis, Myrocarpus frondosus and Balfourodendron riedelianum . Data from the interviews suggest that several species from the Lauraceae family and Schefflera morototoni, Aralia warmingiana, Machaerium stipitatum, Chrysophyllum marginatum had an increment in use and commercial value during the last 15 years. Changing in the commercial value of a species was pointed out as due not only to the timber quality but also to the amount of the timber availability. Overall, it was detected that the species values changed across time and that the timber industry found several ways to adapt to the demands of forest products.

Avaliação do Potencial Energético de Bambusa vulgaris em Função da Idade

ABSTRACT The use of sewage sludge biochar (SSB) for agro-environmental purposes has been increasing. However, due to the strong influence of pyrolysis temperatures on its production, there is great variation in its final properties. In this regard, efforts to generate relationships among many correlated SSB properties may help to understand this influence. This study sought to evaluate the effect of pyrolysis temperature on agro-environmental physicochemical properties of SSB. Biochars from sewage sludge (SS) were produced at 300, 400 and 500°C and their physicochemical properties were evaluated in comparison to SS samples. The increase in pyrolysis temperature decreased C, N, and H contents and the H/C atomic ratio, while increasing the C/N ratio. The pyrolysis process increased pH values, the surface area and pore volume and enriched the SSB with macro and micronutrients. Considering all variables together, the biochar produced at 300°C was that which showed the greatest nutrients availability, such as N total, S, NO3−, NH4+, Ca2+ and Mg2+. Conversely, SSB produced at 500°C showed higher recalcitrant organic matter and alkalinity, important properties for C sequestration and the correction of acidic soils. The combined application of SSB produced at lower and higher pyrolysis temperatures should be furthered studied.

Avaliação da segurança e ocorrência de defeitos na operação de corte semimecanizado de florestas de eucalipto

ABSTRACT One of the main advantages of using biochar for agricultural purposes is its ability to store carbon (C) in soil for a long-term. Studies of labile and stable fractions of soil organic matter (SOM) may be a good indicator of the dynamics of biochar in soils. This study evaluated the effects of applying sewage sludge biochar (SSB) in combination with mineral fertilizer on fractions of SOM. To conduct this evaluation, 15 Mg ha−1 of SSB combined or not with mineral fertilizer (NPK) was applied to the soil in two cropping seasons. Apart from total organic C (TOC), the labile and stable fractions of SOM were also determined. The combined use of SSB and NPK resulted in higher TOC, a 22% to 40% increase compared to the control and to the NPK treatments, respectively. The SSB produced at a lower temperature increased the labile fractions of SOM, especially the microbial biomass C, showing its capacity to supply nutrients in the short-term. The stable pools of SOM are increased after adding SSB produced at a higher temperature. It was concluded that pyrolysis temperature is a key-factor that determines the potential of SSB to accumulate C in labile and stable fractions of SOM.