Graduation Semester and Year




Document Type


Degree Name

Doctor of Philosophy in Earth and Environmental Science


Earth and Environmental Sciences

First Advisor

Melanie L Sattler


Environmental pollution causes ongoing problems. Many countries are faced with the dilemma of finding alternative energy sources that are cost-effective and environmentally friendly. Biofuels have received much attention of late as potential alternative fuels. Although biofuels are indeed attractive energy sources, their manufacturing also brings environmental pollution. One of the most prominent biofuels is ethanol. In the US, the main feedstock for ethanol manufacturing is corn. In Brazil, as well as in some other countries, the main raw material is sugarcane. Although ethanol presents many advantages as a biofuel, including the fact that it is manufactured from renewable resources, there are several disadvantages associated with its waste disposal, including the uncontrolled disposal of `raw' vinasse (or stillage) onto agricultural fields in some countries. This work includes development of one treatment solution for the aforementioned problems. The main goal of this research is to develop a mathematical model for predicting methane production rates from the anaerobic digestion of ethanol vinasse. This model is named VUMP (Vinasse Utilization for Methane Production). The effects of six parameters (temperature in the mesophilic range, COD, N, P, K, and S) on methane generation in a batch bioreactor have been studied. Methane generation vs. time was measured, and used to develop a multiple linear regression model for predicting methane generation rate as a function of the 6 parameters. VUMP model estimates were then compared with CH4 generation rates from actual vinasse.


Earth Sciences | Physical Sciences and Mathematics


Degree granted by The University of Texas at Arlington