(486t) Model Based Biodiesel Supply Chain Optimization

Biodiesel is industrially produced by transesterification of vegetable fatty oils with methanol. Most commonly used vegetable oils are rapeseed (Europe), soybean (America),

sunflower, palm oil (Asia) and even waste cooking oil. Fatty oils are essentially mixtures of saturated and unsaturated mixed triglycerides of long-fatty acid chains that chemically react with the alcohol to produce a mixture of fatty acid alkyl esters. Different production schemes have been analyzed including the use of basic or acid catalysts (Freedman et al., 1984,Varma and Madras, 2007) and more recently, enzymes. The noncatalytic production at the alcohol supercritical conditions has also been studied (Espinosa et al., 2007; 2009). However, production cost is mainly determined by raw material cost; i.e., oil costs.

In this work, we address the optimization of biodiesel supply chain through the formulation of an MINLP problem. We include simplified models for oil extraction plants as well as more detailed models for biodiesel plants ranging from catalytic (basic and acid) to noncatlytic processes. Inventory and transportation costs have been also included and these last ones greatly contribute to the economical objective function. Numerical results give a novel insight on the soybean oil based biodiesel supply chain in Argentina.

References

Freedman, B., Pryde E.H., Mounts T.L., 1984. Variables affecting the yields of fatty esters

from transesterified vegetable oils. JAOCS 61, 1638-1643.

Espinosa, S., M.S. Diaz, E. Brignole, Process synthesis and optimization of a supercritical methanol biodiesel production plant, ECCE-6, 6th European Congress of Chemical Engineering (Copenhagen, 16-20 september 2007), 423-424.

Espinosa, S., M.S. Diaz, E. Brignole, Model-based optimization in supercritical biodiesel production plants, 10th International Symposium on Process Systems Engineering - PSE2009.

Varma, M.N., Madras, G., 2007. Synthesis of Biodiesel from Castor Oil and Linseed Oil in Supercritical Fluids. Ind. Eng. Chem. Res. 46, 1-6.