title: Remediation of trichloroethylene-contaminated soils by star technology using vegetable oil smoldering.
abstract: Self-sustaining treatment for active remediation (STAR) is an innovative soil remediation approach based on smoldering combustion that has been demonstrated to effectively destroy complex hydrocarbon nonaqueous phase liquids (NAPLs) with minimal energy input. This is the first study to explore the smoldering remediation of sand contaminated by a volatile NAPL (trichloroethylene, TCE) and the first to consider utilizing vegetable oil as supplemental fuel for STAR. Thirty laboratory-scale experiments were conducted to evaluate the relationship between key outcomes (TCE destruction, rate of remediation) to initial conditions (vegetable oil type, oil: TCE mass ratio, neat versus emulsified oils). Several vegetable oils and emulsified vegetable oil formulations were shown to support remediation of TCE via self-sustaining smoldering. A minimum concentration of 14,000 mg/kg canola oil was found to treat sand exhibiting up to 80,000 mg/kg TCE. On average, 75% of the TCE mass was removed due to volatilization. This proof-of-concept study suggests that injection and smoldering of vegetable oil may provide a new alternative for driving volatile contaminants to traditional vapour extraction systems without supplying substantial external energy.
authors.affiliation: Department of Civil and Environmental Engineering, University of Western Ontario, London, Ontario N6A 5B9, Canada.
authors.forename: Madiha
authors.initials: M
authors.lastname: Salman
authors.affiliation: Department of Civil and Environmental Engineering, University of Western Ontario, London, Ontario N6A 5B9, Canada. Electronic address: jgerhard@uwo.ca.
authors.forename: Jason I
authors.initials: JI
authors.lastname: Gerhard
authors.affiliation: Savron, 130 Research Lane, Guelph, Ontario N1G 5G3, Canada.
authors.forename: David W
authors.initials: DW
authors.lastname: Major
authors.affiliation: Department of Civil and Environmental Engineering, University of Western Ontario, London, Ontario N6A 5B9, Canada.
authors.forename: Paolo
authors.initials: P
authors.lastname: Pironi
authors.affiliation: Department of Civil and Environmental Engineering, University of Western Ontario, London, Ontario N6A 5B9, Canada.
authors.forename: Rory
authors.initials: R
authors.lastname: Hadden
mesh_terms: D052918:Environmental Restoration and Remediation / Q000379:methods*; D006358:Hot Temperature; D010938:Plant Oils; D012989:Soil Pollutants / Q000737:chemistry*; D014241:Trichloroethylene / Q000737:chemistry*; D014835:Volatilization
chemical_list: D010938:Plant Oils; D012989:Soil Pollutants; D014241:Trichloroethylene
keywords: NAPL; Remediation; Smoldering; Thermal; VOCs; Vegetable oil