Enhancing removal efficiency of heavy metals and ammonia in bioretention system using quartz sand and zeolite as filter media

Bioretention is one of the stormwater runoff managements to reduce pollutant concentration such as heavy metals and ammonia. However, removal efficiency of bioretention was affected by variation of filter media. So, the aims of this study are to enhance removal efficiency of bioretention system. Three bioretention system were applied on pilot scale sized 30 × 30 × 80 cm3 combined with Iris pseudacorus. Variation of filter media composition of quartz sand and zeolite was used with ratio 1:3, 1:1, 3:1, on reactor 1, 2 and 3, respectively. Synthetic runoff water with different concentration were simulated. The results shown that variations in influent concentrations has small effect on the removal efficiency (20-40%). The average removal efficiency of bioretention 1, 2 and 3 for Pb was 91%, 78%, 83%, respectively, followed 88%, 95%, 94% for Zn and 97%, 98%, 96% for NH3. The combination of quartz sand and zeolite as filter media significantly enhance removal efficiency by 11,5% for NH3, 18% Pb and 20% Zn compared to previous similar research.