1 research outputs found
Biochar and Activated Carbon for Enhanced Trace Organic Contaminant Retention in Stormwater Infiltration Systems
To assess the effectiveness of biochar
and activated carbon (AC)
for enhanced trace organic contaminant (TOrC) retention in stormwater
infiltration systems, an approach combining forward-prediction modeling
and laboratory verification experiments was employed. Batch and column
tests were conducted using representative TOrCs and synthetic stormwater.
Based on batch screening tests, two commercially available biochars
(BN-biochar and MCG-biochar) and an AC were investigated. The AC exhibited
the strongest sorption, followed by MCG-biochar and BN-biochar. Langmuir
isotherms provided better fits to equilibrium data than Freundlich
isotherms. Due to superior sorption kinetics, 0.2 wt % MCG-biochar
in saturated sand columns retained TOrCs more effectively than 1.0
wt % BN-biochar. A forward-prediction intraparticle diffusion model
based on the Langmuir isotherm adequately predicted column results
when calibrated using only batch parameters, as indicated by a Monte
Carlo uncertainty analysis. Case study simulations estimated that
an infiltration basin amended with F300-AC or MCG-biochar could obtain
sorption-retarded breakthrough times for atrazine of 54 or 5.8 years,
respectively, at a 1 in./h infiltration rate. These results indicate
that biochars or ACs with superior sorption capacity and kinetics
can enhance TOrC retention in infiltration systems, and performance
under various conditions can be predicted using results from batch
tests