Floating treatment wetlands for synthetic greywater remediation

Abed, SN 2017, Floating treatment wetlands for synthetic greywater remediation , PhD thesis, University of Salford.

Download (5MB) | Preview


Aggravation of water scarcity, eutrophication and pollution, has led to treatment and/or recycling of the major fraction of domestic wastewater, which is grey wastewater, for non‒potable options. The major aim of this study was to evaluate the performance of FTWs for remediation of various pollutants from synthetic greywater. In the present study, a novel synthetic greywater composition has been proposed with respect to the composition of organics, nutrients, heavy metals and other trace elements. As an imitation of bio‒physiochemical treatment technology, mesocosm‒scale retention ponds were artificially retrofitted with floating reedbed Phragmites australis to introduce, what is known as, floating treatment wetlands (FTWs) for improving the removal efficiency of soluble contaminations from synthetic greywater (SGW) in such systems. As a corroboration to the phytoremediation, pelletised ochre (acid mine wastewater sludge) was added into those FTWs for its capacity to adsorb phosphorus and other trace elements. Mainly, four operational variables were designated for the experimental design set‒ups of the FTWs, namely: pollutant strength (high‒ (HC) and low‒ (LC) concentrations), contact time (2‒ and 7‒day), presence of P. australis and presence of cement‒ochre pellets. The findings revealed that dissolved (DO), and biochemical and chemical oxygen demands (BOD5 and COD) decreased significantly (p < 0.05) in all FTWs. The concentrations of NO3‒N were significantly (p < 0.05) higher, and of PO4‒P were significantly (p < 0.05) lower than those concentrations of inflow, however, there were no significant (p > 0.05) changes in NH4‒N concentration in FTWs using a combination of ochre pellets with floating P. australis. Presence of ochre pellets in combination with P. australis significantly (p < 0.05) decreased Al, B, Cd, Cr, Cu, Mg, Ni and Zn, while increasing Al, Ca, Fe and K contents in the outflow. Accumulation of all considered elements was significantly (p < 0.05) higher in P. australis of all treatment systems (T) than in control systems (C), except for sodium (Na) contents which had significantly (p < 0.05) lower accumulations. The statistical analysis showed that accumulated concentrations of all considered elements in ochre pellets after the end of the treatment experiment were significantly (p < 0.05) higher, except for Ca concentrations which were significantly (p < 0.05) lower, than those in ochre pellets before commencing the experiment.

Item Type: Thesis (PhD)
Schools: Schools > School of Computing, Science and Engineering
Depositing User: Suhail Najem Abed
Date Deposited: 15 Jan 2018 11:34
Last Modified: 27 Aug 2021 20:39
URI: http://usir.salford.ac.uk/id/eprint/42227

Actions (login required)

Edit record (repository staff only) Edit record (repository staff only)


Downloads per month over past year