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Waste glass as a substrate for As removal from drinking waters in Bangladesh: a laboratory and field-based study

03 December 2011
This research project examines the application of recycled glass and waste stainless steel fragments as a practical medium for As removal at a household scale.

My name is Sultana Kudrati Khoda. I am from Bangladesh, studying for a PhD at the University of Brighton under the supervision of Professor Marie Harder and Professor Andy Cundy.  My research work is based on the "Arsenic removal from ground water using recycled glass granules and waste stainless steel fragments as a filter media. The experiments were performed in the laboratory of Brighton University and in Bangladesh with the technical support from Department of Soil, Water and Environment, University of Dhaka.

The study involves the shaking of glass granules and stainless steel fragments with synthetic arsenic solutions, filtration of synthetic arsenic solutions and natural arsenic contaminated water using both media and characterization of both media using SEM, XRD, PXRF and sequential extraction.

A number of low-cost natural and synthetic filtration media have been proposed for the removal of arsenic (As) from drinking water in areas such as Bangladesh, where exposure to environmental As is a major human health issue. This PhD research project examines the application of recycled glass and waste stainless steel fragments as a practical medium for As removal at a household scale. To assess the performance of recycled glass media as a practical filter bed, glass granules were differentiated by colour, size and mode of preparation (imploded and ground) and used as media for batch adsorption and column filtration experiments. As removal capacity was assessed using a prepared As (III) test solution.

Field experiments were also performed in Bangladesh using larger column filters (750ml volume) and local As-contaminated groundwater. Filter media made from recycled glass and waste stainless steel fragments (introduced during the recycling and preparation process of glass) were also characterised via SEM, XRD, PXRF, and sequential extraction experiments were performed on used filtration media to assess As removal and adsorption processes.

Results indicate that glass granules can remove As from drinking water at an efficiency suitable for household application. Arsenic removal efficiency depends on the presence of other ions such as Fe, Mn, P etc. in the treated water. The presence of waste stainless steel fragments in the filtration medium significantly improved adsorption capacity. The glass particle size and mode of size reduction was also found to influence the removal of As: smaller ground glass was better than imploded glass of the same size. The results, coupled with the low cost of waste glass, indicates that the glass should be investigated further for use in domestic water filtration for As.

Sultana Kudrati Khoda1, Andrew Cundy1, Marie Harder1, Imamul Huq2

Contact: sultanakhoda@yahoo.co.uk

1 Faculty of Science and Engineering, University of Brighton, Brighton, BN2 4GJ, UK.

2 Department of Soil, Water and Environment, University of Dhaka, Bangladesh.

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