O Brasil é um dos maiores produtores de soja e, consequentemente, gera uma grande quantidade de resíduos provenientes dessa cultura, os quais poderiam ser aproveitados na confecção de aglomerados. Este trabalho objetivou analisar as características físico-mecânicas de painéis aglomerados, produzidos com partículas de resíduos de soja e eucalipto, tratadas em água fria e hidróxido de sódio. Adotou-se uma proporção de 50:50 de partículas de eucalipto e casquilho de soja. A densidade nominal dos painéis foi 0,60 g/cm³. Foi utilizado adesivo uréia-formaldeído com teor de sólidos de 12 %. Foram adotados três tratamentos: partículas tratadas com água fria e partículas tratadas com NaOH (com concentração de 1%, além de um tratamento com partículas controle. Os componentes químicos dos materiais lignocelulósicos foram quantificados para as três situações. Os parâmetros do ciclo de prensagem foram: 4 MPa (pressão), 150 °C (temperatura), durante 8 min. Foram observadas reduções nos teores de extrativos totais, após os tratamentos. Em relação às propriedades físicas, os tratamentos aplicados nas partículas não demonstraram eficiência, pois não trouxeram melhorias para a estabilidade dimensional dos painéis e nenhum dos tratamentos atingiram ao valor mínimo especificado pela norma utilizada. Para as propriedades mecânicas, os painéis produzidos com partículas tratadas com água atenderam as exigências para o MOE. Para as propriedades de tração perpendicular e dureza Janka, todos os painéis alcançaram os valores especificados pela NBR 14810 (2013). As outras propriedades testadas (MOR, APS e APT) não atenderam a norma. Os tratamentos aplicados nas partículas de soja e eucalipto não demonstraram eficiência para as propriedades físicas, porém algumas propriedades mecânicas atenderam aos requisitos mínimos da NBR 14810 (2013) para painéis não estruturais para uso interno em ambiente seco (Tipo P2).
The present work aimed at providing knowledge in new sanitation techniques for rural populations and all those who wish to live in a more sustainable way, developing an adequate treatment for their effluents generated in their daily lives. A large part of the Brazilian population does not have basic sanitation or has inadequate forms, such as septic tanks that contaminate the soil and subsequently the water resources of the entire region, with pathogens. Thinking about this idea, an ecologically sustainable way was developed for the treatment of black waters, the Evapotranspiration Basin (BET) with the innovation of the ash box. The sewage coming from the toilet is directed to the ash box built of waterproofed masonry, where it receives preliminary treatment, a gridded basket inside the box retaining coarse solids. In this same box wood ash is added that acts as a flocculant and PH regulator, optimizing the anaerobic digestion process inside the chamber formed by tires in the Evapotranspiration Basin, an impermeable masonry tank submerged in the soil where bacteria remineralize all organic matter. The water contained in the sewage passes through an ascending granulometric filter until it reaches the roots of the plants, where it goes through a natural process of Evapotranspiration, returning a large part of this purified water to the environment. The objective was to compare the budgets of other works and show the economic viability of a BET with the innovation of the ash box.
In this study, the effect of different concentrations of calcium hydroxide (Ca(OH)2) was evaluated as a pre-treatment for accelerated carbonation and its influence on the fibrillation of cellulosic pulps to obtain nanofibrils, and its application as a coating agent for papers. Eucalyptus (EUC) and Pine (PIN) unbleached cellulosic fibers were submitted to pre-treatment with Ca(OH)2 at concentrations of 5 and 10% and subjected to accelerated carbonation, being subsequently mechanically fibrillated to produce cellulose nanofibrils (CNF). Pretreatment with calcium hydroxide followed by accelerated carbonation provided a 35% reduction in energy consumption. Cellulosic pulps EUC and PIN pretreated with calcium hydroxide showed higher fibrillation efficiency. There was a reduction in the cobb test values for papers coated with CNF in PIN. The WVP was lower for papers coated with CNF of EUC and control PIN. The CNF coating of EUC and PIN provided an oil barrier for the kit 11 solution. The CNF coating improved the dispersion of PVA and PVOH. The papers coated in this work have the potential to be used as packaging for fatty and oily foods or as a spreading agent for other industrial coatings.
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