Experimental and Numerical Investigations on Wastewater Treatment using Constructed Wetlands

Abstract

Availability of safe and clean water is one of the important requirements for ensuring newlinegood health of the public. Improper disposal of untreated sewage is a major cause of newlinewater pollution all over the world. Efficient and effective wastewater treatment and newlineproper disposal of treated wastewater are very important for maintaining and improving newlinethe quality of surface and subsurface sources of water. Conventional methods of newlinewastewater treatment are highly capital and energy intensive. It is well known and newlinedocumented as well, that natural wetlands can perform treatment of poor-quality water newlineby natural means. In addition to this, these wetlands also serve as a natural habitat for newlinevarious plant and animal species. Large tracts of such wetlands have been destroyed in newlinethe last three to four decades on various pretexts. In recent years, constructed wetlands newlinehave gained the ground as engineered systems that employ natural processes and newlinecomponents for treating wastewater. Also known as treatment wetlands , these are a low newlinecost decentralized sustainable wastewater treatment alternative to conventional treatment newlinesystems and can be adopted in many situations for remediating water pollution problems. newlineIn this research, the performance of vertical subsurface flow constructed wetlands was newlineevaluated with specific reference to the removal of some typical pollutants such as newlineammonia nitrogen, nitrite nitrogen and phosphorus from wastewater and the factors that newlinecritically affect its performance were identified. Experimental studies were carried out on newlinepilot scale constructed wetland units. Two varieties of vegetation were adopted in this newlinestudy, viz., Amaranthus dubius and Euphorbia milii. The percentage removal and mass newlineremoval rate of each of the pollutants were determined. The vertical subsurface flow newlineconstructed wetlands, were operated in two modes in the intermittent mode and in the newlinebatch mode. From the experimental studies on pilot scale units.