Abstract
Constructed wetland is a low cost, effective technology and it is still in the state of improvement to enhance the treatment efficiency, especially in nutrient and trace elements treatment. This study investigated the effect of aerobic and anoxic conditions in Horizontal Subsurface Flow Constructed Wetland (HSFCW) on nutrient, organic, metal and Octylphenol - OP (Endocrine disrupting chemical) treatment. Two HSFCWs were constructed: HSFCW1 with three aerobic compartments; HSFCW2 with two aerobic compartments, one anoxic compartment. The two HSFCWs had the same design parameters (fiters, plants), except oxygen conditions. The results showed that aerobic and anoxic HSFCW may increase the efficiency of Nitrogen removal by 10%, but decreased by 11% in the efficiency of OP treatment (one of the EDCs). The efficiency of treatment of pollutants, including NH4+-N, COD, TP, Mn, Fe, Al and Cu between two HSFCWs were not significantly different; the average efficiency was 99%, 84%, 97%, 96%, 96%, 72% and 73%, respectively. Therefore, the anoxic compartment of HSFCW still provided the effective removal of organic matter, Manuscript received September 29th, 2017; accepted 24th December, 2017 This study was funded by CARE RESCIF under grant number Tc-TTC-2017-05. An Truong Nguyen, Tam Minh Thi Le, Viet Quoc Tran, Trang Huyen Thi Nguyen are with the CARE, Ho Chi Minh City University of Technology, VNU-HCM, Vietnam (truongan.hcmut@gmail.com, minhtamnt2006@hcmut.edu.vn, ngthtrang@hcmut.edu.vn) Viet Ngoc Truong, Luan Thanh Nguyen, Phi Hoang Tan Nguyen are with the Faculty of Environment and Natural Resources, Ho Chi Minh City University of Technology, VNU- HCM, Vietnam (truongngocviet93@gmail.com) metals and octylphenol, but it also improved nitrogen removal efficiency by up to 92%.
Highlights
Inefficient wastewater treatment or directed discharge pollutants containing nutrient contaminants, organic (e.g. BOD, Chemical Oxygen Demand (COD)), hazardous and trace elements (Antibiotics, pesticides, endocrine disrupting chemicals – EDCs) can pollute the water environment
Constructed Wetlands (CWs) are built to simulate the processes of treating pollutants in the nature, SCIENCE & TECHNOLOGY DEVELOPMENT JOURNAL, VOL 20, NO.K9-2017 with the appropriate human modification for efficient wastewater treatment through the physical and chemical, biological processes thanks to the composition of plant, filter materials and microorganisms [5], they can remove 51% total nitrogen concentration (TN), 54% Total Phosphorus (TP), 63% COD and hazardous substances such as metals, EDCs [6]
There was a significant difference in the concentrations of NH4+-N or NO3--N in the second compartment between two Horizontal Subsurface Flow Constructed Wetland (HSFCW) (P < 0.01) which helped HSFCW2 get the TN removal ability better than HSFCW1, as results 92% and 82% of TN treatment efficiency, respectively
Summary
Inefficient wastewater treatment or directed discharge pollutants containing nutrient contaminants (nitrogen, phosphorus), organic (e.g. BOD, COD), hazardous (e.g. metals, PCB) and trace elements (Antibiotics, pesticides, endocrine disrupting chemicals – EDCs) can pollute the water environment. The heavy metals are removed or retained through several mechanisms including: uptake of vegetations, adsorption on sediment or deposition in by both aerobic and anoxic/anaerobic processes [7]. These mechanisms work on EDCs removal by constructed wetlands, because the main removal pathways of the target EDCs is their biodegradation [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
