Electronic Thesis and Dissertation Repository

Degree

Master of Engineering Science

Program

Civil and Environmental Engineering

Supervisor

Dr. Jason Gerhard

Abstract

Self-sustaining Treatment for Active Remediation (STAR), a smouldering combustion-based technology for remediating sites contaminated by industrial liquids, has been extensively studied in the laboratory. The technology had not been demonstrated at a real site. Moreover, the ignition method (based on heat conduction) for the process used in the laboratory was not appropriate for field deployment and an alternative was required. This work first presents the development of a new ignition method for smouldering combustion. This ignition technique (based on heat convection) was proven effective via laboratory tests, and then applied and improved through two field tests. These field tests, conducted on coal tar-contaminated soils below the water table at a former industrial facility, represent the first in situ demonstrations of the STAR technology. Self-sustained smoldering was demonstrated within two soil layers at the site: a fill located 3 m below ground surface (bgs) (shallow test) and a sand located 8 m bgs (deep test). The shallow test destroyed 3,728 kg of coal tar over 10 days while the deep test destroyed 864 kg of coal tar over 10 days. Concentration reductions of 99.3% and 97.3% were achieved in soils within the treated areas of the shallow and deep tests, respectively. The performance of the technology in the field (rate the reaction travelled, peak temperatures, extent of cleanup, spread of drying zone) was found to be consistent with the previous laboratory studies. Overall, this work successfully transitions the smouldering remediation concept shown in the laboratory to a field-proven technology with a robust ignition technique that allows rapid, effective deployment at contaminated sites.


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