A MASS TRANSFER MODEL OF ETHANOL EMISSION FROM THIN LAYERS OF CORN SILAGE

作者：El Mashad H M; Zhang R^*; Rumsey T; Hafner S; Montes F; Rotz C Alan; Arteaga V; Zhao Y; Mitloehner F M

来源：Transactions of the ASABE, 2010, 53(6): 1903-1909.

• Corn silage
• Dairy farms
• Ethanol emissions
• Mass transfer coefficient
• Modeling
• VOC emissions

A mass transfer model was developed and validated to predict ethanol emission from thin layers of corn silage. The model was developed using experimental data collected from silage placed in a wind tunnel under different temperatures and air velocities. Data from the wind tunnel experiments were used to derive a multiple regression equation that related the overall mass transfer coefficient of ethanol to temperature and air velocity. Evaluation of the model was done using data collected from experiments conducted in a controlled environmental chamber. Ethanol emission was determined from the ventilation rate of the environmental chamber and ethanol concentration in the chamber exhaust over a 24 It period, measured using a photoacoustic gas analyzer. Ethanol concentration in the silage was also monitored throughout the duration of each experiment. Predicted ethanol emission rates were strongly correlated (R(2) = 0.94) with values measured in the environmental chamber. A high correlation (R(2) = 0.96) was also found between predicted and measured ethanol concentrations in the silage. The model was used to estimate ethanol emission rates from thin layers of lightly packed silage on a dairy farm in California. Model predictions indicate that most of the ethanol contained in the silage could be emitted in the first 10 h after exposing the silage to ambient air temperature (18 degrees C to 35 degrees C) and air velocity (0.1 to 2.0 m s(-1)).

• 出版日期2010-12