[Study on the low temperature drying of components of municipal solid waste and its model analysis]

The drying behaviors of four typical municipal solid waste (MSW) components (including waste paper, textile, pericarp and wood) were studied under low temperature. Effects of temperature on drying characteristic, thin layer drying models, effective moisture diffusion coefficient and activation energy were investigated in this paper. Experimental results showed that with increasing temperature, the drying rate increased, but the added value reduced gradually. Four mathematical models were used to simulate drying curves of MSW components. Modified Page model was found to give better predictions when moisture content was more than 25%. Based on the Fick's second law, the effective moisture diffusion coefficient for waste paper, textile, pericarp and wood were 8.24 x 10(-8)-23.67 x 10(-8), 7.73 x 10(-8)-12.56 x 10(-8), 3.57 x 10(-8)-14.18 x 10(-8) and 6.51 x 10(-8)-23.84 x 10(-8)m2 x s(-1). The activation energy determined through Arrhenius equation were 25.26, 10.75, 32.16 and 29.49 kJ x mol(-1), respectively. Carried on the similar dry experiments to practical MSW, It was found that Modified Page model was also suitable for simulating the drying process of practical MSW, its effective moisture diffusion coefficient and activation energy were 6.78 x 10(-8)-18.65 x 10(-8)m2 x s(-1) and 22.36 kJ x mol(-1), respectively.