Conference Proceeding

Sustainable wastewater treatment: Reverse Osmosis rejected water purification through biochar engrained bio-geo filters.

In Reverse Osmosis (RO) water purification systems about 50-70% of raw water with higher concentrations of ions release from RO systems to the inland waters or directly to the ground with no beneficial use. Such practice will end up with long term environmental impacts. This research was focused to investigate a remedial measure for concentrated contaminants of RO rejected water through photo remediation using construction wetlands, before discharging into the natural environment. Two types of constructed wetlands (CW): surface and subsurface water CW were established and tested to measure the removal efficiency of RO concentrates through photo remediation and media materials through field application at a community based RO water supply unit. Native soil, burnt clay roof tiles pieces and bio char were engrained with proportions of 80, 17.5 and 2.5% by weight respectively as media materials. Vertiver Grass and Scirpus Grossus were employed for the sub surface wetland while Water Lettuce and Water Hyacinth were chosen for free water surface CW. Experimental set ups were fed with uniform flow of RO concentrate and water quality parameters were tested periodically against two controls systems for given hydraulic retention time. The results showed that Total Dissolved Solids, Hardness, Total Alkalinity and Fluoride were reduced significantly and met desirable levels of stipulated ambient standards. This study indicated a great promise of purifying aforesaid contaminants of water which is obvious and considerable in ground water sources. Bio char engrained Bio-Geo Filters showed promising results with very low construction and maintenance cost as this approach directly dealt with locally available aquatic plants and eco friendly bio-geo filter materials. Therefore the invented biochar engrained bio-geo constructed wetland system is an economical and effective option for reducing high concentrations of RO rejected water before discharging into the soil- water environment.

Published: 01 August 2017


Copyright: © 2017 Bandunee C L Athapattu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.