Dynamical modeling for biodiesel production from grease trap wastes

• A dynamical model for biodiesel production was proposed.
• The biodiesel was produced via the esterification of grease trap wastes within a CSTR.
• The esterification runs were conducted under load and temperature variations.
• Esterification data were fitted to the model with a proposed regression algorithm.
• The proposed model has been validated with the runs test using low-cost measurements.

Grease trap wastes have been recently considered as an alternative feedstock for biodiesel production due to its relatively low cost and availability. These wastes are characterized by a high content of free fatty acids (FFA) and then, its processing towards biodiesel requires an esterification. In this paper, a dynamical model for the esterification of grease trap wastes was constructed. Specifically, this process has been conducted within a continuous stirred tank reactor. Almost all the parameters contained in the dynamical model were deduced from a series of batch temperature-controlled esterification experiments and from thermodynamic essays. The rest of the model parameters have been successfully estimated by means of a proposed algorithm that combines the notion of sensitivity with the Levenberg–Marquardt procedure. This regression procedure provides the estimates in spite of load and temperature variations and processing low-cost measurements. Finally, the proposed dynamical model has been validated with the runs test.