egon.cheme.cmu.edu/Papers/Mariano_Integrated_algae_bioethanol_biodiesel.pdf

http://egon.cheme.cmu.edu/Papers/Mariano_Integrated_algae_bioethanol_biodiesel.pdf

Optimal engineered algae composition for the 

integrated simultaneous production of bioethanol 

and biodiesel 

Mariano Martína, 1, Ignacio E. Grossmannb 

aDepartamento de Ingeniería Química. Universidad de Salamanca. Plz. Caidos 1-5 37008 Salamanca (Spain) 

bDepartment of Chemical Engineering Carnegie Mellon University. Pittsburgh, PA 15213 

 

 

Abstract. 

In this paper we present the optimization of the composition of the algae for the simultaneous production of bioethanol and biodiesel. We consider two alternative technologies for the biodiesel synthesis from algae oil, enzymatic or homogeneous alkali catalyzed, the most promising based on previous work, and we coupled biodiesel production from oil with bioethanol production from algae starch. In order to determine the optimal operating conditions we not only couple the technologies, but simultaneously optimize the production of both biofuels and heat integrate them. Multieffect distillation column for the beer column is included in the flowsheet to mitigate the energy and cooling water consumption derived from the ethanol dehydration. In both cases the optimal algae composition results in 60% oil, 30% starch and 10% Protein. The cheaper alternative for the production of biofuels corresponds to a production price of 0.35 $/gal, using the enzymatic catalyzed path with promising energy and water consumption 

values (4.20 MJ/gal & 0.61 gal/gal). 

Keywords: Energy; Biofuels; Bioethanol; Biodiesel, Process integration