title: Performance assessment of aquatic macrophytes for treatment of municipal wastewater.
abstract: The objective of the study was to evaluate the performance of three different aquatic macrophytes for treatment of municipal wastewater collected from Taxila (Pakistan). A physical model of treatment plant was constructed and was operated for six experimental runs with each species of macrophyte. Every experimental run consist of thirty days period. Regular monitoring of influent and effluent concentrations were made during each experimental run. For the treatment locally available macrophyte species i.e. water hyacinth, duckweed & water lettuce were selected to use. To evaluate the treatment performance of each macrophyte, BOD5, COD, and Nutrients (Nitrogen and Phosphorus) were monitored in effluent from model at different detention time of every experimental run after ensuring steady state conditions. The average reduction of effluent value of each parameter using water hyacinth were 50.61% for BOD5, 46.38% for COD, 40.34% for Nitrogen and 18.76% for Phosphorus. For duckweed the average removal efficiency for selected parameters were 33.43% for BOD5, 26.37% for COD, 17.59% for Nitrogen and 15.25% for Phosphorus and for Water Lettuce the average removal efficiency were 33.43% for BOD5, 26.37% for COD, 17.59% for Nitrogen and 15.25% for Phosphorus. The mechanisms of pollutant removal in this system include both aerobic and anaerobic microbiological conversions, sorption, sedimentation, volatilization and chemical transformations. The rapid growth of the biomass was measured within first ten days detention time. It was also observed that performance of macrophytes is influenced by variation of pH and Temperature. A pH of 6-9 and Temperature of 15-38°C is most favorable for treatment of wastewater by macrophytes. The option of macrophytes for treatment of Municipal sewage under local environmental conditions can be explored by further verifying the removal efficiency under variation of different environmental conditions. Also this is need of time that macrophyte system should be used for treatment of wastewater because their performance is comparable to conventional wastewater treatment plants and also the system has very low O&M costs.
authors.affiliation: Department of Civil and Environmental Engineering, UET, Taxila, Pakistan.
authors.forename: Mumtaz
authors.initials: M
authors.lastname: Shah
authors.affiliation: Department of Civil Engineering, UET, Taxila, Pakistan.
authors.forename: Hashim Nisar
authors.initials: HN
authors.lastname: Hashmi
authors.affiliation: Civil Engineering Department, MCE, Rasalpur, Pakistan.
authors.forename: Arshad
authors.initials: A
authors.lastname: Ali
authors.affiliation: Department of Civil Engineering, UET, Taxila, Pakistan.
authors.forename: Abdul Razzaq
authors.initials: AR
authors.lastname: Ghumman
keywords: Aquatic macrophytes; BOD5; Duckweed; NEQS; Phytoplankton; Plant growth; Waste stabilization ponds
references.citation: Water Res. 2002 Feb;36(4):1007-17
references.pmid: 11848339
references.citation: J Hazard Mater. 2003 Feb 28;97(1-3):193-205
references.pmid: 12573838
references.citation: J Environ Sci (China). 2007;19(8):902-9
references.pmid: 17966845