Source: http://bibliotekevirtual.org/index.php/2013-02-07-03-02-35/2013-02-07-03-03-11/111-rcm/v01n02/196-v01n02a03.html
Timestamp: 2019-04-20 00:43:52+00:00

Document:
Efeito de Pré-Tratamentos na Taxa de Secagem da Madeira de Hovenia dulcis Thunb.
Resumo: O estudo teve por objetivo avaliar o efeito de pré-tratamentos na taxa de secagem da madeira de uva-do-japão (Hovenia dulcis Thunb.). Para isso, amostras de madeira com dimensões de 2,0 x 10,0 x 20,0 cm (E x L x C) foram submetidas aos pré-tratamentos de imersão em água quente e de congelamento. Os pré-tratamentos foram conduzidos em um tanque térmico a 85ºC (aquecimento) e em freezer a -18ºC (congelamento), onde as amostras permaneceram durante 12 ou 24 horas para ambos os casos. Posteriormente, as amostras de madeira foram submetidas à secagem em estufa elétrica a temperaturas de 60 ou 90ºC, até atingirem o equilíbrio. A taxa de secagem foi significativamente influenciada pelos pré-tratamentos, temperatura de secagem e duração dos mesmos. E apresentou comportamento diferenciado de acordo com a duração do tratamento: com 12h o aquecimento foi superior; com 24h o congelamento foi o que mais se destacou. Com o aumento da duração e da temperatura, observou-se a tendência de aumento da taxa de secagem.
Abstract: This study aimed to evaluate the effect of pre-treatments on drying rate of uvado-japão wood (Hovenia dulcis Thunb.). For this, samples of wood species concerned with dimensions of 2,0 x 10,0 x 20,0 cm (E x L x C), were subjected to pre-treatment of soaking in hot water and freezing. The pre- treatments of heating and freezing were conducted in a thermal tank at 85ºC and a freezer at -18ºC, respectively, where the samples remained for 12 and 24 hours for both treatments. After the pre-treatments, the wood samples were dried in an electric oven at temperatures of 60 and 90°C until the final moisture content. The drying rate was significantly influenced by pre-treatments, drying temperature and their duration of them. This rate presented a different behavior according to the duration of treatment: the warning was higher with 12hours whereas the freezing, with 24 hours, was more evident. The increasing duration and temperature observed showed that the tendency of the drying rate is to increase.
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