Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

A Mass Transfer Model of Ethanol Emission from Thin Layers of Corn Silage

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan

Citation:  Transactions of the ASABE. 53(6): 1903-1909. (doi: 10.13031/2013.35800) @2010
Authors:   H. M. El-Mashad, R. Zhang, T. Rumsey, S. Hafner, F. Montes, C. Alan Rotz, V. Arteaga, Y. Zhao, F. M. Mitloehner
Keywords:   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 h 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 (R2 = 0.94) with values measured in the environmental chamber. A high correlation (R2 = 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°C to 35°C) and air velocity (0.1 to 2.0 m s-1).

(Download PDF)    (Export to EndNotes)