Integrating Tank Model and adsorption/desorption characteristics of filter media to simulate outflow water quantity and quality of a bioretention basin: A case study of biochar-based bioretention basin

Nian Hong; Qin Cheng; Buddhi Wijesiri; Erick R Bandala; Ashantha Goonetilleke; An Liu

doi:10.1016/j.jenvman.2021.114282

Integrating Tank Model and adsorption/desorption characteristics of filter media to simulate outflow water quantity and quality of a bioretention basin: A case study of biochar-based bioretention basin

J Environ Manage. 2022 Feb 15:304:114282. doi: 10.1016/j.jenvman.2021.114282. Epub 2021 Dec 15.

Authors

Nian Hong¹, Qin Cheng¹, Buddhi Wijesiri², Erick R Bandala³, Ashantha Goonetilleke², An Liu⁴

Affiliations

¹ College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China.
² College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China; School of Civil and Environmental Engineering, Queensland University of Technology (QUT), GPO Box 2434, Brisbane, Qld, 4001, Australia.
³ Division of Hydrologic Sciences, Desert Research Institute, 755 E Flamingo Rd., Las Vegas, NV, 89119, USA.
⁴ College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China; Water Science and Environmental Engineering Research Center, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China. Electronic address: liuan@szu.edu.cn.

PMID: 34920283
DOI: 10.1016/j.jenvman.2021.114282

Abstract

Reliable approaches for accurately assessing the performance of stormwater treatment systems is essential for their effective design, including filter media selection which can be a significant constituent in stormwater treatment systems. This study presents an innovative modelling approach integrating the Tank Model with the adsorption-desorption characteristics of the filter media. The resulting modelling approach was applied to simulate a field-scale bioretention basin where biochar was used as filter media with over ten years of rainfall records. The resulting outflow and overflow volumes were compared with observed data for calibration. The Stormwater Treatment Tank Model (STTM) was validated using the Leave-One-Out-Cross-Validation (LOOCV) method. The simulation outcomes include water outflow and overflow (quantity) from the bioretention basin as well as outflow water quality represented by three heavy metals (Pb, Cu, and Zn). The modelling approach developed was found to be capable of accurately simulating outflow and overflow volumes, with outlet water quantity being significantly influenced by the total rainfall depth. The modeling results also suggested that a sole treatment system would not be adequate, particularly for large rainfall events (>100 mm) and a treatment train would be more effective. Simulating long-term (over ten years) pollutant removal performance in the bioretention basin indicated that heavy metals outflow event mean concentration (EMCs) values calculated using simulated results of 30% biochar application rate generated the best pollutant removal with consistent values (2.7 μg/L, 3.0 μg/L, 17.2 μg/L for Pb, Cu, and Zn, respectively). These results confirm that the modelling approach is reliable for assessing long-term treatment performance, as well as a robust tool able to contribute to more effective treatment system design, particularly filter media selection and evaluation.

Keywords: Biochar; Bioretention basin; Heavy metals; Stormwater quality; Stormwater quantity; Tank model.

MeSH terms

Adsorption
Charcoal
Rain*
Water Purification*
Water Supply

Substances

biochar
Charcoal