36 research outputs found
Método De Preparação De Materiais Lignocelulósicos Para Análise Macroscópica
Método de preparação de materiais lignocelulósicos para análise macroscópica, do tipo que pode ser empregado para a preparação de amostras tais como madeira e similares e que compreender três etapas básicas, sendo que, a primeira etapa consiste no corte e polimento mecânico das amostras; a segunda etapa compreende a digitalização, tratamento e caracterização das imagens obtidas; e a terceira etapa consiste na aplicação das informações obtidas a partir das imagens digitalizadas e tratadas da segunda etapa.BR9905465 (A)D21B1/00D21B1/00BR19999905465D21B1/00D21B1/0
Processo De Obtenção De Compositos Biomassa Vegetal E Aglomerantes Inorgânicos Para Construção E Produto Assim Obtido
A presente invenção se refere a um processo de obtenção de um compósito biomassa vegetal e aglomerantes inorgânicos para ser usado como material de construção. Mais especificamente, o processo consiste das seguintes etapas: a) pré-tratamento da biomassa vegetal, composta de resíduos de exploração agro-industrial, em água, durante 0 a 3 horas A uma temperatura que varia entre 20 e 90oC; b) tratamento de impermeabilização da biomassa vegetal através da pulverização de soluções à base de cimento, betume e sais inorgânicos, com deposição de resíduos sólidos de 0 a 10% em relação a massa das partículas; c) dissolução na água de amassamento de 0 a 4% de produto acelerador da pega (cloretos, sulfatos, silicatos), em relação à massa de aglomerante. O produto é obtido através da mistura manual ou mecânica de 1 parte de aglomerante, (cimento ou substituído de 0-60% oir gessom oak iy calcário agrícola) de 1 a 5 partes de agregado mineral miúdo, de 1 a 6 partes de biomassa vegetal tratada e de 0,5 a 2 partes da solução aquosa (dosagens volumétricas) e por esta mistura ser depositada em formas e submetida à vibração manual ou mecânica por 0 a 10 minutos), sendo o material desformado, curado de 0 a 60 minutos em reator fechado dispondo de CO2, recoberto por lona plástica durante 0 a 24 horas e submetido de 0 a 5 ciclos de umidificação e secagem durante 0 a 28 dias.BR9504705 (A)C04B18/24C04B18/24BR19959504705C04B18/24C04B18/2
Bambu: Matéria-prima para o Século XXI
Apresentação feita pelo Professor Beraldo durante o ENSUS 201
Effect of wood particle treatment on the properties of gypsum plaster pastes and composites
In this work the performance of gypsum plaster and wood particle in pastes and composites was investigated. Wood particles of fineness 0.42 mm and 1.20 mm were employed. Natural wood particles and the treated ones in cold or hot water (80 °C) were performed. The effects of the extractives solutions from the treatments applied to the wood particles on wood-gypsum compatibility were studied. For pastes and composites, water-to-gypsum ratio was 0.65. Wood particles-to-gypsum plaster ratios were 5%, 10% and 15%, in mass. Kinetics of temperature, mechanical performance and dynamic elasticity modulus by ultrasound measurements were applied to evaluate the gypsum plaster pastes and its composites behaviors. Results show that the extractive solutions changed the time of gypsum plaster hydration, being more sensitive to hot water treatment. The composites compressive strength increase with the wood particles pretreatment. The best result was to room temperature treatment. The same performance was found to the modulus of elasticity. Treatments have improved significantly the flexural strength. The best wood particle content was 10%. These results show the possibility of using this wood waste with an easy and simple treatment to make eco-efficient building materials.2141032104
EFFECTS OF THERMAL TREATMENT ON THE PHYSICOCHEMICAL CHARACTERISTICS OF GIANT BAMBOO
Despite countless use possibilities for bamboo, this material has two major disadvantages. One drawback is the low natural durability of most bamboo species due to presence of starch in their parenchyma cells. The other equally important drawback is the tendency bamboo has to present dimensional variations if subjected to environmental change conditions. In an attempt to minimize these inconveniences, strips (laths) of Dendrocalamus giganteus Munro were taken from different portions of the culm and subjected to several temperatures, namely 140 degrees C, 180 degrees C, 220 degrees C, 260 degrees C and 300 degrees C under laboratory conditions, at the ESALQ-USP college of agriculture. The thermal treatment process was conducted in noninert and inert atmospheres (with nitrogen), depending on temperature Specimens were then subjected to physicomechanical characterization tests in order to determine optimum thermal treatment conditions in which to preserve to the extent possible the original bamboo properties. Results revealed that there is an optimum temperature range, between 140 degrees and 220 degrees C, whereby thermally treated bamboo does not significantly lose its mechanical properties while at the same time showing greater dimensional stability in the presence of moisture.17336136
Boards made of bamboo (Bambusa vulgaris Schrad) particles and castor oil-based polyurethane resin
The aim of this study was to manufacture and evaluate particleboards made with two alternative materials, seeking to develop a sustainable production process. Particles from Bambusa vulgaris Schrad were used because of the fast production cycle of this species. The binder used was castor oil (Ricinus communis L.) based polyurethane resin, since it is partially produced by a renewable source and it is considered to be non-toxic. For the characterization of the material, boards made of bamboo particles smaller than 2.4 mm, combined with 5%, 10% and 15% resin content in relation to the bamboo-particle mass, were manufactured at laboratory scale. Specimens were evaluated according to the Brazilian standard NBR 14810 - agglomerate wood boards. Before the longitudinal compression tests, the specimens were tested by means of a non-destructive ultrasound evaluation. The results showed that the boards with 10% resin content were not statistically different from those with 15% resin content, and both were superior to boards with 5% resin content. Most of the board properties were inferior to those of commercial boards. It was not possible to correlate ultrasonic pulse velocity across the specimens with longitudinal compression strength.Esta investigación tiene como objetivo la elaboración y la evaluación de tableros de partículas homogéneas aglomeradas, utilizándose dos materiales alternativos en la búsqueda de la sustentabilidad del proceso productivo. Fueron utilizadas partículas de Bambusa vulgaris Schrad por la rapidez del ciclo de producción de esta especie de bambú. Como pegante fue utilizada la resina poliuretana a base de aceite de ricino (Ricinus communis L.), por su origen parcialmente renovable, y por ser considerada no tóxica. Para la caracterización del material, fueron fabricadas, en escala de laboratorio, tableros de partículas de bambú con dimensiones inferiores al 2.4 mm, combinadas con 5%, 10% y 15% de resina en relación a la masa de partículas de bambú. Probetas fueron evaluadas de acuerdo con las especificaciones de la norma NBR 14810 - Tableros de madera aglomerada. Antes de los ensayos de compresión las probetas fueron evaluadas por medio del ensayo no destructivo por ultra-sonido. Los resultados obtenidos indicaron que los tableros con el contenido de 10% de resina no fue estadísticamente diferente al contenido de 15%, siendo ambos superiores al contenido de 5%. La mayoría de las propiedades de los tableros fueron inferiores a aquellas de los tableros comerciales. No fue posible correlacionar la velocidad del pulso de ultra-sonido con la resistencia a la compresión longitudinal.25926
Tableros de partículas de bambú (Bambusa vulgaris Schrad) y resina poliuretana a base de aceite de rícino (Ricinus communis L.)
Esta investigación tiene como objetivo la elaboración y la evaluación de tableros de partículas homogéneas aglomeradas, utilizándose dos materiales alternativos en la búsqueda de la sustentabilidad del proceso productivo. Fueron utilizadas partículas de Bambusa vulgaris Schrad por la rapidez del ciclo de producción de esta especie de bambú. Como pegante fue utilizada la resina poliuretana a base de aceite de ricino (Ricinus communis L.), por su origen parcialmente renovable, y por ser considerada no tóxica. Para la caracterización del material, fueron fabricadas, en escala de laboratorio, tableros de partículas de bambú con dimensiones inferiores al 2.4 mm, combinadas con 5%, 10% y 15% de resina en relación a la masa de partículas de bambú. Probetas fueron evaluadas de acuerdo con las especificaciones de la norma NBR 14810 - Tableros de madera aglomerada. Antes de los ensayos de compresión las probetas fueron evaluadas por medio del ensayo no destructivo por ultra-sonido. Los resultados obtenidos indicaron que los tableros con el contenido de 10% de resina no fue estadísticamente diferente al contenido de 15%, siendo ambos superiores al contenido de 5%. La mayoría de las propiedades de los tableros fueron inferiores a aquellas de los tableros comerciales. No fue posible correlacionar la velocidad del pulso de ultra-sonido con la resistencia a la compresión longitudinal
Evaluation of preservative treatment of bamboo strips with pyroligneous acid
A baixa resistência natural do bambu ao ataque de organismos xilófagos constitui uma das principais limitações ao seu pleno uso. O objetivo do presente estudo foi avaliar o efeito do ácido pirolenhoso no tratamento preservativo de taliscas de bambu-gigante contra fungos deterioradores. Para tal, foi realizado um ensaio de apodrecimento acelerado em laboratório com taliscas testemunhas (sem tratamento) e taliscas tratadas com o produto diluído em água fervente nas concentrações 0%, 5%, 10%, 20% e 30%, adotando-se tempos de imersão 15, 45, 90 e 180 minutos. As taliscas de bambu foram testadas após 6 e 16 semanas de exposição. Foram efetuadas inspeções visuais nas taliscas e aplicados ensaios não destrutivos de perda de massa e por ultrassom (6 e 16 semanas) e ensaios de flexão estática (após 16 semanas). Os resultados obtidos nos ensaios não destrutivos não evidenciaram o efeito dos fatores testados (tipo de solo, duração do tratamento e concentração da solução) nessas propriedades. A análise visual indicou apenas um ataque superficial nas taliscas, não evidenciando perda de massa. No ensaio de flexão estática, verificou-se o efeito favorável da duração do tratamento nos módulos de elasticidade (Em0) e de ruptura (MOR). O tipo de solo (natural ou estéril) não apresentou influência no módulo de elasticidade, enquanto que a concentração da solução não influenciou o módulo de ruptura.Palavras-chave: Bambu-gigante; biodeterioração; fungos deterioradores. AbstractEvaluation of preservative treatment of bamboo strips with pyroligneous acid. Bamboo presents a low natural resistance to decay, which constitutes one of the major limitations to its use. This study aims to evaluate pyroligneous acid effect against fungal bamboo deterioration through an accelerated laboratory decay with testing reference (without treatment) and treated specimens with the product diluted in boiling water at (0%, 5%, 10%, 20% and 30%) in different immersion times (15, 45, 90, and 180 minutes). Bamboo splits were evaluated after 6 and 16 weeks of exposure. Visual inspections and non-destructive tests (mass loss and ultrasound at 6 and 16 weeks) and bending (after 16 weeks) were applied to the bamboo strips. Results of the non-destructive tests did not allow to detect the effect of the factors (soil type, immersion time and solution concentration) on these properties. Only a superficial attack was observed by visual inspection, which did not denote mass loss. Immersion time shows a positive effect on modulus of elasticity (Em0) and on modulus of rupture (MOR). Moduli of elasticity and rupture were not influenced by soil type (sterile or natural), or by the concentration of the solution, respectively.Keywords: Giant bamboo; biodeterioration; fungi decay.AbstractBamboo presents a low natural resistance to decay, which constitutes one of the major limitations to its use. This study aims to evaluate pyroligneous acid effect against fungal bamboo deterioration through an accelerated laboratory decay with testing reference (without treatment) and treated specimens with the product diluted in boiling water at (0%, 5%, 10%, 20% and 30%) in different immersion times (15, 45, 90, and 180 minutes). Bamboo splits were evaluated after 6 and 16 weeks of exposure. Visual inspections and non-destructive tests (mass loss and ultrasound at 6 and 16 weeks) and bending (after 16 weeks) were applied to the bamboo strips. Results of the non-destructive tests did not allow to detect the effect of the factors (soil type, immersion time and solution concentration) on these properties. Only a superficial attack was observed by visual inspection, which did not denote mass loss. Immersion time shows a positive effect on modulus of elasticity (Em0) and on modulus of rupture (MOR). Moduli of elasticity and rupture were not influenced by soil type (sterile or natural), or by the concentration of the solution, respectively.Keywords: Giant bamboo; biodeterioration; fungi decay
Effect of wood particle treatment on the properties of gypsum plaster pastes and composites
In this work the performance of gypsum plaster and wood particle in pastes and composites was investigated. Wood particles of fineness 0.42 mm and 1.20 mm were employed. Natural wood particles and the treated ones in cold or hot water (80 °C) were performed. The effects of the extractives solutions from the treatments applied to the wood particles on wood-gypsum compatibility were studied. For pastes and composites, water-to-gypsum ratio was 0.65. Wood particles-to-gypsum plaster ratios were 5%, 10% and 15%, in mass. Kinetics of temperature, mechanical performance and dynamic elasticity modulus by ultrasound measurements were applied to evaluate the gypsum plaster pastes and its composites behaviors. Results show that the extractive solutions changed the time of gypsum plaster hydration, being more sensitive to hot water treatment. The composites compressive strength increase with the wood particles pretreatment. The best result was to room temperature treatment. The same performance was found to the modulus of elasticity. Treatments have improved significantly the flexural strength. The best wood particle content was 10%. These results show the possibility of using this wood waste with an easy and simple treatment to make eco-efficient building materials.Keywords: Gypsum plaster, wood particle, composite, ultrasound, kinetics of temperature