Authors

Thu Phuong Pham 1* , Dai Quyet Truong 2 , Duc Tung Le 1 , Viet Quang Nguyen 1

Affiliations

1 School of Environmental Science and Technology, Hanoi University of Science and Technology; phuong.phamthu@hust.edu.vn; leductung96@gmail.com; nv.quang2027@gmail.com

2 School of Civil and Environmental Engineering, University of Technology Sydney (UTS), City Campus, Broadway, NSW 2007, Australia; quyettruongdai@gmail.com

*Corresponding author: phuong.phamthu@hust.edu.vn; Tel.: +84–902299312

Abstracts

The objective of this study was to establish a standard experimental model to determine the removal rate constants of wastewater pollutants in subsurface flow–constructed wetlands. Such the rate constants of removal processes of removal processes of COD, BOD, NH4+, total nitrogen (TN), etc., are important parameters for calculating the size of wetlands, yet the data published in the international textbooks and research articles fluctuate in very wide ranges, that make it challenging to design constructed wetland accurately. By evaluating influencing factors and referencing available models, we proposed the experimental wetland model of cylindrical shape (Ø18cm and 30cm height), with the type of material and plant, which must be specified for each experiment determining the rate constants. The experimental procedure has been given, including setting up the system, running experiments to collect data, and processing data to calculate the rate constant. The initial experiments with small gravel and common reed plant, determining the removal rate constants of COD, NH4+ and TN, provided good repeatability results, and the values are within a reasonable range with the published values in the world. This result shows the applicability of the proposed experimental model and procedure to determine the contaminant removal rate constants in constructed wetlands uniformly. Eventually, a complete set of more converging rate constants data can be obtained, which improves the accuracy of the constructed wetlands setup.

Keywords

Subsurface flow constructed wetland; Rate constant; Ammonium; COD; Total nitrogen

Cite this paper

Thu, P.P.; Dat, Q.T.; Duc, T.L.; Viet, Q.N. Proposal of a standard experimental model to determine the contaminant removal rate constants in subsurface flow constructed wetlands. VN J. Hydrometeorol 2023, 14, 36-44. 

References

1. Kadlec, R.H.; Wallace, S.D. Treatment Wetlands. 2nd ed., Taylor & Francis Group, Boca Raton, 2009.

2. Vymazal, J.; Sengupta, M.; Dalwani, R. (Editors). Constructed Wetlands for Wastewater Treatment: A Review, In Proceedings of the World Lake Conference, Jaipur, Rajasthan, India, 28 October – 2 November 2007, 2008, 965–980.

3. Crites, R.; George, T. Small and Decentralized Wastewater Management systems. McGraw–Hill Higher Education, USA, 1998, pp. 1104.

4. Reed, S.C.; Crites, R..; Middlebrooks, E.J. Natural Systems for Waste Management and Treatment: 2nd edition. McGraw–Hill, New York, USA, 1995.

5. Magdalena, G.; Katarzyna, S.; Krzysztof, J.; Zbigniew, M.; Włodzimierz, W.; Agnieszka, K. P. Kinetics of pollutants removal in vertical and horizontal flow constructedwetlands in temperate climate. Sci. Total Environ. 2020, 718, 137371.

6. Haiming, W.; Jian, Z.; Huu, H.N.; Wenshan, G.; Zhen, H.; Shuang, L.; Jinlin, F.; Hai, L. A review on the sustainability of constructed wetlands for wastewater treatment: Design and operation. Bioresour. Technol. 2015, 175, 594–601.

7. Magdi, E.K.; Gaber, Y.; El–Reash, A.; Ahmed, M.I.; Rizk, F.W. Effect of media variation on the removal efficiency of pollutants from domestic wastewater in constructed wetland systems. Ecol. Eng. 2020, 143, 105668.

8. Cao, S.; Jing, Z.; Yuan, P.; Wang, Y. Wang, Y. Performance of constructed wetlands with different substrates for the treated effluent from municipal sewage plants. J. Water Reuse Desalin. 2019, 9(4), 452–462.

9. Abdelhakeem, S.G.; Aboulroos, S.A.; Kamel, M.M. Performance of a vertical subsurface flow constructed wetland under different operational conditions. J. Adv. Res. 2016, 7, 803–814.

10. Villasen˜, J.; Mena, J.; Ferna´ndez, F.J.; Go´mez, R.; de Lucas, A. Kinetics of domestic wastewater COD removal by subsurface flow constructed wetlands using different plant species in temperate period. Int. J. Environ. Anal. Chem. 2010, 91(7), 693–707.

11. Trang, N.T.D.; Dennis, K.; Hans–Henrik, S.; Chiem, N.H.; Tuan, L.A.; Hans, B. Kinetics of pollutant removal from domestic wastewater in a tropical horizontal subsurface flow constructed wetland system: Effects of hydraulic loading rate. Ecol. Eng. 2010, 36(4), 527–535.

12. Pérez, M.M.; Hernández, J.M.; Bossens, J.; Jiménez, T.; Rosa, E.; Tack, F. Vertical flow constructed wetlands: kinetics of nutrient and organic matter removal. Water Sci. Technol. 2014, 70(1), 76–81.

13. von Sperling, M.; de Paoli, A.C. First–order COD decay coefficients associated with different hydraulic models applied to planted and unplanted horizontal subsurface–flow constructed wetlands. Ecol. Eng. 2013, 57, 205–209.

14. Sonavane, P.G.; Munavalli, G.R. Modeling nitrogen removal in a constructed wetland treatment system. Water Sci. Technol. 2009, 60(2), 301–309.

15. Weerakoon, G.M.P.R.; Jinadasa, K.B.S.N.; Manatunge, J.; Wijesiri, B.; Goonetilleke, A. Kinetic modelling and performance evaluation of vertical subsurface flow constructed wetlands in tropics. J. Water Process Eng. 2020, 38, 101539.

16. Adelaide, A.; Fátima, C.; Maria J. Imaginário.; Ivone, C.; Ana R. Prazeres.; Carlos Ribeiro. Nitrate removal in vertical flow constructed wetland planted with Vetiveria zizanioides:  Effect of hydraulic load. Ecol. Eng. 2017, 99, 535–542.