Determinação do equilíbrio higroscópico e do calor isostérico do bagaço de cana-de-açúcar

Abstract

This study aimed to determine the hygroscopic equilibrium and isosteric heat of sugarcane bagasse to evaluate sorption dynamics and the required energy to vaporize water in the bagasse dehydration. The reaction was assessed at different controlled conditions of temperature (20, 40, 55 and 70 ºC) and air relative humidity (10, 12, 17, 18, 30, 40, 45, 50, 60 and 85%), as well as testing various models described in the literature to identify the condition that better represents sorption behavior. As a result, we found that the model that best fit empirical data of sugarcane bagasse sorption was the modified Henderson with determination coefficient of 0.972; while the integral isosteric heat of desorption ranged from 2,524.09 to 2,951.95 kJ kg-1 , for all water contents and equilibrium of 0.014 until 0.170 bs, respectively.