Biomass as a Sustainable Energy Source: An Illustration of Chemical Engineering Thermodynamic Concepts


  • Marguerite A. Mohan Manhattan College
  • Nicole May Manhattan College
  • Nada M. Assaf-Anid
  • Marco J. Castaldi Manhattan College


The ever-increasing global demand for energy has sparked renewed interest within the engineering community in the study of sustainable alternative energy sources. This paper discusses a power generation system which uses biomass as “fuel” to illustrate the concepts taught to students taking a graduate level chemical engineering process thermodynamics course. The students were asked to propose solutions as to how a bioreactor might be used to decompose the biomass anaerobically and subsequently generate power. The purpose of the assignment was to give the students a better understanding of chemical thermodynamics by incorporating abstract thermodynamic principles, such as fugacity, solubility, and multi-phase equilibrium and to give them a chance to apply these principles to a relevant, practical, and open-ended situation. Specifically, the students were required to provide a full understanding of the bioreactor, and to develop the appropriate thermodynamic relationships to determine preferred system conditions which would accelerate the decomposition process. Among the characteristics examined were the types of byproducts formed, how these byproducts distribute themselves between the liquid and vapor phases, and the preferred concentration of carbon in the feed stream as a function of residence time, temperature, and pressure.

Author Biographies

Marguerite A. Mohan, Manhattan College

Marguerite A. Mohan is currently working towards her M. S. in chemical engineering at Manhattan College, where she previously obtained a 8. S. in chemical engineering. After completing her graduate degree, she will be employed full time by Merck & Co., Inc., as a staff chemical engineer. Marguerite's research interests include chemical thermodynamics and nanoscale science.

Nicole May, Manhattan College

Nicole May is currently pursuing her M.S. in chemical engineering at Manhattan College. She also holds a 8 . S. in chemical engineering from Manhattan College. Her interests include engineering education, bioreaction engineering, and environmental conservation.

Nada M. Assaf-Anid

Nada M. Assaf-Anid is an associate professor and chairperson of the Chemical Engineering Department at Manhattan College. She earned her 8 .S. and M.S. in chemical engineering from the Royal Institute of Technology in Stockholm, Sweden, and her Ph.D. in environmental engineering from the University of Michigan in Ann Arbor. Her research and teaching interests are in separations, biochemical engineering, hazardous chemicals remediation, thermodynamics, and water purification. She is director of the ASEE Chemical Engineering Division and director of the Environmental Division of AIChE.

Marco J. Castaldi, Manhattan College

Marco J. Castaldi is an assistant professor in the Earth and Environmental Engineering Department at Columbia University. He received his B.S. ChE from Manhattan College, and M.S. and Ph.D. ChE from the University of California, Los Angeles. Prior to joining Columbia University, he worked in industry for seven years researching and developing novel catalytic reactors. His teaching interests lie in thermodynamics, combustion phenomena, and reaction engineering. His research is focused on beneficial uses of CO, in catalytic and combustion environments, waste-to-energy processes, and novel extraction techniques for methane hydrates.