ENERGY EFFICIENCY AND PERFORMANCE OF A COFFEE GRAIN DRYER USING CONCURRENT AND COUNTER-CURRENT FLOWS

• Autor(a) principal: Martin, Samuel
• Data de Publicação: 2009
• Outros Autores: Silva, Jadir Nogueira da, Lacerda Filho, Adílio Flauzino de, Queiroz, Daniel Marçal de, Zanatta, Fabio Luiz
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Engenharia na Agricultura
• Texto Completo: https://periodicos.ufv.br/reveng/article/view/124
• topic: Pós-colheita; secador; café

This study was done to evaluate the performance and energy efficiency of a coffee grain dryer using concurrent and counter-current air flow. The first concurrent flow drying stage was separated from the second counter-current flow stage by a repose chamber. The first drying treatment was characterized by intermittent drying with mixing with the air at 45°C, and the second by intermittent drying with continuous reflux at the air at 70°C. In the first drying system initial and final moisture contents were 33.9 ± 5.0 and 11.8 ± 0.7% (w.b.), respectively, compared to 29.0 ± 3.6 and 11.6 ± 1.0% in the second treatment. The grain temperature remained within the recommended values for coffee. Intermittent drying, with continuous mixing, at 70°C consumed less energy compared to the intermittent drying with intermittent mixing at 45°C, and there was greater specific energy consumption in tests where the drying was concluded in few hours after the repose period.