| Popis: |
Stormwater runoff from roads and parking lots often contains toxic pollutants which may pose risks to biota in receiving aquatic systems. Low impact development (LID) designs such as rain gardens and infiltration swales can improve stormwater quality. Adding biochar as a soil amendment or standalone filtration layer can enhance pollutant removal. Biochar exhibits surface properties, allowing for high sorption of inorganic and organic toxic pollutants such as heavy metals, petroleum hydrocarbons, and pesticides. Biochar production is cost-effective and can be an environmentally sustainable technology. The objective of this paper is to investigate the efficacy of biochar as a filtration media for removing naphthalene, copper, and zinc found in a heavy use parking lot in Burnaby, BC, Canada. A commercially available biochar was used as the filtration media, while sand was used as a benchmark filtration media. Effects of runoff pH, contaminant concentrations, total organic carbon concentration, and biochar size on removal efficiency were examined. Filtration experiments using biochar showed high copper and zinc removal similar to sand. However, biochar filters showed a higher naphthalene removal efficiency compared to sand. Results from the study showed that biochar is a promising filtration media for LIDs in storm water source control designs. |
