TY - JOUR
T1 - Stormwater biofilter treatment model for faecal microorganisms
AU - Shen, Pengfei
AU - Deletic, Ana
AU - Urich, Christian
AU - Chandrasena, Gayani I.
AU - McCarthy, David T.
PY - 2018/7/15
Y1 - 2018/7/15
N2 - This paper presents a new model to simulate long-term microbial removal in stormwater biofilters. The water flow module uses a ‘three-bucket’ approach to describe the flow processes in biofilters, while the microbial quality module employs the one-dimensional advection-dispersion equation to represent microbial transport and fate under different design and operational conditions. Three governing processes for microbial removal, adsorption, desorption and die-off, are included; temperature is also incorporated as a key factor for die-off. The model was tested using long term monitoring data collected from laboratory columns in which five different biofilter configurations were studied over a period of 44 weeks. A multi-objective calibration with the balance of instantaneous ponding levels and event outflow volumes was implemented on the water flow module, and the Nash-Sutcliffe Efficiency (E) values ranged from 0.82 to 0.95. The microbial quality module was tested using the effluent Escherichia coli concentration data, and the E values obtained for different configurations were between 0.46 and 0.68. The optimized parameter values agreed with those presented in literature. However, sensitivity analyses suggested that the model's prediction was not sensitive to all parameters, the explanation for which was hypothesized to be data paucity rather than model structural uncertainties. Model validation was also conducted by splitting the data into calibration and validation datasets. The results further reinforced the needed for more data for model calibration.
AB - This paper presents a new model to simulate long-term microbial removal in stormwater biofilters. The water flow module uses a ‘three-bucket’ approach to describe the flow processes in biofilters, while the microbial quality module employs the one-dimensional advection-dispersion equation to represent microbial transport and fate under different design and operational conditions. Three governing processes for microbial removal, adsorption, desorption and die-off, are included; temperature is also incorporated as a key factor for die-off. The model was tested using long term monitoring data collected from laboratory columns in which five different biofilter configurations were studied over a period of 44 weeks. A multi-objective calibration with the balance of instantaneous ponding levels and event outflow volumes was implemented on the water flow module, and the Nash-Sutcliffe Efficiency (E) values ranged from 0.82 to 0.95. The microbial quality module was tested using the effluent Escherichia coli concentration data, and the E values obtained for different configurations were between 0.46 and 0.68. The optimized parameter values agreed with those presented in literature. However, sensitivity analyses suggested that the model's prediction was not sensitive to all parameters, the explanation for which was hypothesized to be data paucity rather than model structural uncertainties. Model validation was also conducted by splitting the data into calibration and validation datasets. The results further reinforced the needed for more data for model calibration.
KW - Biofilter
KW - Escherichia coli
KW - Faecal microorganisms
KW - Microbial removal
KW - Modelling
KW - Stormwater
UR - http://www.scopus.com/inward/record.url?scp=85042702312&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2018.02.193
DO - 10.1016/j.scitotenv.2018.02.193
M3 - Article
C2 - 29554784
AN - SCOPUS:85042702312
VL - 630
SP - 992
EP - 1002
JO - Science of the Total Environment
JF - Science of the Total Environment
SN - 0048-9697
ER -