Evaluation of Biochar as a Potential Filter Media for the Removal of Mixed Contaminants from Urban Storm Water Runoff

Abstract

Urban storm water runoff can carry a wide range of contaminants, many of which exceed federal maximum contaminant levels, into surface water resources (e.g., rivers and lakes). The use of filtration systems has received greater attention for its potential to remove particulate matter and other contaminants. Biochar is expected to have excellent potential as an adsorbent or filter given its large surface area and microporous structure. This study evaluated the potential use of biochar as a filter media through a series of column experiments. A column with an inner diameter of 7 cm (2.75 in.) and a length of 61 cm (24 in.) using biochar as filter media was constructed to examine its effectiveness for the removal of mixed contaminants [total suspended solids (TSS), nutrients, heavy metals, polycyclic aromatic hydrocarbons (PAHs), and