Doctoral defence in Chemical Engineering - Aysan Safavi

Doctoral candidate: Aysan Safavi

Title of thesis: Developing the next generation of pyrolysis reaction models

Opponents
Dr. Patricia Taboada-Serrano, Associate Professor, Rochester Institute of Technology, USA
Dr. Timo Kikas, Professor, Estonian University of Life Sciences, Estonia

Advisors
Dr. Rúnar Unnþórsson, Professor and Head of the Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, University of Iceland
Dr. Christiaan Richter, Professor at the Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, University of Iceland

Also in the doctoral committee
Dr. Jorge Mario Marchetti, Professor, Norwegian University of Life Sciences, Norway

Chair of Ceremony
Dr. Helmut Wolfram Neukirchen, Professor and Vice Head of  the Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, University of Iceland

Abstract
Municipal solid waste incineration has been identified as a major source of dioxins in the air, leading to the closure of many European incinerators. While gasification of waste and biomass has been considered a more environmentally friendly alternative, it is not always guaranteed to meet regulatory emission limits. Pyrolysis, a sub-section of the gasification process, is a sustainable technique used to produce biofuels and is known for its low-emission properties. This thesis evaluates the applicability of widely used wood pyrolysis models and two proposed models by conducting experiments on walnut shells and reviewing existing experimental data on woody material and plastic waste pyrolysis. The analysis suggests that conventional models are inadequate for predicting pyrolytic product yields at higher temperatures and additional reactions must be accounted for. This thesis makes a significant contribution to the field of woody/plastic pyrolysis by demonstrating that incorporating secondary tar and char reactions into the reaction scheme improves the accuracy and predictive capabilities of kinetic models. An understanding of the kinetic characterization of pyrolysis is fundamental to advancing the field. This study aims to assist researchers in conducting relevant research for improving and optimizing pyrolysis processes.

About the doctoral candidate
Aysan finished her Bachelor’s degree in Chemical Engineering-Petroleum Engineering in Iran before she started her master’s program in Environmental Engineering-Renewable Energy Engineering in Iceland back in 2012. During her master’s studies, Aysan conducted research with Iceland's primary waste management company SORPA bs. The focus of her MSc project was on developing batch-scale and semi-industrial-scale operations for biogas production. Before starting her doctoral studies, she spent a year at the Technical University of Denmark as a researcher, with a focus on bio-energy and ammonia-rich fertilizer production.

Aysan's Ph.D. project centered on sustainable waste-to-bio-energy production via pyrolysis, incorporating both modeling and experimental research. As part of her research, she collaborated with the Chemical Engineering faculty at Queen Mary University of London to delve into the fundamental aspects of biomass pyrolysis for energy generation. Aysan is continuing her research on pyrolysis.