Impact of hydraulic and carbon loading rates of constructed wetlands on contaminants of emerging concern (CECs) removal.
Constructed wetlands remove trace organic contaminants via synergistic processes involving plant biomass that include hydrolysis, volatilization, sorption, biodegradation, and photolysis. Wetland design conditions, such as hydraulic loading rates (HLRs) and carbon loading rates (CLRs), influence these processes. Contaminant of emerging concern (CEC) removal by wetland plants was investigated at varying HLRs and CLRs. Rate constants and parameters obtained from batch-scale studies were used in a mechanistic model to evaluate the effect of these two loading rates on CEC removal. CLR significantly influenced CEC removal when wetlands were operated at HLR >5 cm/d. High values of CLR increased removal of estradiol and carbamazepine but lowered that of testosterone and atrazine. Without increasing the cumulative HLR, operating two wetlands in series with varying CLRs could be a way to improve CEC removal.
School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, AZ 85287, USA. Electronic address: fsharif@asu.edu.
Fariya
F
Sharif
School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, AZ 85287, USA.
Paul
P
Westerhoff
Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA.
Pierre
P
Herckes
D001673:Biodegradation, Environmental; D018533:Biomass; D002244:Carbon / Q000032:analysis*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D057446:Hydrodynamics; D010944:Plants; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
D014874:Water Pollutants, Chemical; D002244:Carbon
Carbon loading rate (CLR); Constructed wetland; Contaminants of emerging concern (CECs); Hydraulic loading rate (HLR); Wastewater