Electronic Thesis and Dissertation Repository


Master of Engineering Science


Civil and Environmental Engineering


Dr. Jason Gerhard


Remediation of sites contaminated with non-aqueous phase liquids (NAPLs) presents a significant challenge, particularly for complex and high molecular weight compounds such as coal tar and creosote. Self-sustaining Treatment for Active Remediation (STAR) is an innovative remediation technology based on the principles of smouldering combustion, which has shown potential for rapid destruction of source zone contaminants. The success of smouldering remediation has been previously demonstrated both at the laboratory and field scale, however, these studies have focused primarily on the overall degree of remediation. Laboratory column experiments were employed to identify key transient processes that have the potential to influence smouldering metrics. It was found that downward liquid fuel mobilization can occur in taller systems operated at low air flow rates, and may result in elevated peak temperatures and a slowing of the propagation velocity of the trailing edge of the smouldering front. Numerical simulations and an analytical model were used to further understand experimental observations and can be used as a simple tool to predict the potential for liquid fuel mobility under different experimental conditions. It was also found that the distribution of heat within a smouldering system influences the transport of condensable products. The processes of fuel volatilization, aerosolization, condensation and deposition are important for gaseous mass transport and impact the rate of mass loss over time. The relative proportion of fuel combustion to gaseous mass transport is expected to be a function of fuel type, and may also be manipulated via operational parameters such as injection air flux.