Wastewater Treatment in Constructed Wetlands by Phytoremediation Technique

¹ Department of Civil Engineering, Mohan Babu University (Erstwhile Sree Vidyanikethan Engineering College), Tirupati, Andhra Pradesh, India
² Department of Civil Engineering, Sri Venkateswara Institute of Science and Technology, Kadapa, Andhra Pradesh, India
³ Department of Civil Engineering, Chennai Institute of Technology, Chennai, Tamil Nadu, India

^--- Corresponding Author: hemadriprasadraju@vidyanikethan.edu

Abstract

Water is the most required element next to air for terrestrial living being. Though the water is everywhere but no direct use is possible as the fresh water is getting contaminated through various human activities. The conventional treatment methods using activated sludge process, attached growth systems such as trickling filters, rotating biological contactors, aerated lagoons and stabilization ponds are normally practiced in many places with each one having its own merits and demerits depending on space availability, energy requirements etc. An alternative solution called phytoremediation method can save energy requirements to the great extent but space required will be more and it can be used advantageously where space is not a constraint. This method involves using plants to absorb and metabolize pollutants found in wastewater, including nutrients such as nitrogen and phosphorus, heavy metals and other organic and inorganic contaminants. In this study, sewage is passed through a bed of plants, which takes up nutrients and contaminants while releasing oxygen during their photosynthesis process. This promotes the growth of beneficial bacteria that further break down pollutants. In the present work, Spider lily (Hymenocallis littoralis) and Heliconia (Heliconia psittacorum) are two species of tropical plants used in constructed wetlands and that have shown potential in the treatment of sewage. Conducted the performance studies on both plants separately. The efficiency achieved with spider lily plants Heliconia plants are 87.2% and 79.6% in BOD removal respectively. These systems are also relatively low-cost and require minimal maintenance, making them a viable option for wastewater treatment in areas where conventional treatment systems may be too expensive or impractical.