Monday, April 30, 2007

A preliminary study of biodiesel production in a novel intensive electrostatic reactor

Satya A. Gangu1, Mauricio Antenzana1, T. Prader2, Jerzy Petera3, and Laurence R. Weatherley1. (1) Department of Chemical and Petroleum Engineering, University of Kansas, 4132 Learned Hall, 1530W. 15th,, Lawrence, KS 66045, (2) Department of Chemical and Process Engineering,, University of Canterbury, New Zealand, (3) Environmental and Process Engineering, The Technical University of Lodz, Lodz, 90-929, Poland

Biodiesel production involves the esterification of a fat or oil feedstock with methyl alcohol under alkaline conditions in a liquid-liquid environment. A novel intensive reactor for more efficient biodiesel production was developed with the goal of intensifying and optimizing the contacting of the caustic/methanol solutions with the fat-based feedstock and, the enhancement of the subsequent phase separation using electrostatic fields based on novel liquid spraying technology. The paper describes the system design and presents preliminary results of drop size and hold-up measurement, reactor performance, and modeling. The feasibility of improving the rate of biodiesel production using electrostatic spraying techniques is demonstrated. Preliminary results of on-line drop size and hold measurements are presented, showing that specific rates of reaction at different positions in the reactor may be determined. The rates of reaction were compared with those determined for a mechanically produced dispersion and were shown to be slightly lower. The phase separation of the two reacting liquids was also compared and significant enhancements were noted. The prediction of the droplet motion, hold-up, and mixing behavior in the reactor is essential for scale-up and future design feasibility determination. Preliminary results are presented demonstrating the ability to accurately predict the motion of discrete drops in the electrostatically enhanced reactor. Further extension to the prediction of the behavior of swarms of fine droplets in an intensified biodiesel reactor using a cloud model approach is discussed.