Metallic Iron Filters for Universal Access to Safe Drinking Water

Abstract

The availability of sustainable safe drinking water is one of Millennium Development Goals (MDGs). The world is on schedule to meet the MDG to ‘halve by 2015 the proportion of people without sustainable access to safe drinking water in 2000’. However, present technologies may still leave more than 600 million people without access to safe water in 2015. The objective of the present article is to present a concept for universal water filters primarily made of metallic iron (Fe0) and sand. The concept of Fe0/sand filters is based on a combination of: (i) recent developments in slow sand filtration and (ii) recent progress in understanding the process of contaminant removal in Fe0/H2O systems. The filters should be made up of more than 60% sand and up to 40% Fe0. The actual Fe0 proportion will depend on its intrinsic reactivity. The most important question to be answered regards the selection of the material to be used. The design of the filter can be derived from existing filters. It appears that Fe0/H2O based filters could be a technology with worldwide applicability.

Enhancing sustainability of household water filters by mixing metallic iron with porous materials

“…This approach was rendered possible by revisiting the nature of Fe 0 -based filters. It was recalled that a filtration system basically works on the size-exclusion principle [14]. Accordingly, at any time, the pore space must be large enough to enable the expansion/compression cycle inherent to iron corrosion.…”

Dimensioning metallic iron beds for efficient contaminant removal

“…In a 50 % Fe 0 bed material depletion (100 % however, a 50:50 weight ratio is usually used based on a pragmatic approach [50]. The technology for household filters [52] and its use for small scale water facilities [42,53]. Fe 0 filter technology is regarded as a flexible and affordable technology, which could enable the achievement of the Millenium Development Goals (MDGs) for water.…”

“…Fe 0 filter technology is regarded as a flexible and affordable technology, which could enable the achievement of the Millenium Development Goals (MDGs) for water. This simple technology could even enable to achieve universal access to safe drinking water within some few years [52]. adsorption front is the saturated zone and the region below is the virgin zone.…”

“…In other words because of insufficient system analysis, the Fe 0 reactive wall technology was demonstrated on a very permeable system but operating walls are necessarily less permeable. Moreover, mixing Fe 0 and sand was considered as a tool to reduced Fe 0 costs [51,52]. It is now demonstrated, that mixing Fe 0 with inert additives is even the prerequisite for sustainability.…”

Appropriate technology for domestic wastewater management in under-resourced regions of the world

“…biphenyls, detergents, dyes, fertilizers, greases, hydrocarbons, oils, pharmaceuticals, personal care products, pesticides, plasticizers, phenols, and surfactants) in aqua system has prompted the development of efficient, applicable, and affordable technologies, in particular, in remote, low-income communities. The use of metallic iron (Fe 0 ) beds has been demonstrated as such an appropriate technology (Ghauch 2015;Noubactep et al 2009;Litter et al 2010;Noubactep 2010a;Noubactep and Schöner 2010;Giles et al 2011;Noubactep 2013a) and design criteria presented (Noubactep and Caré 2010;Noubactep et al 2012a, b;Bilardi et al 2013a, b;Caré et al 2013;Btatkeu-K et al 2014). The suitability of Fe 0 to treat a complex mixture of micro-pollutants arises from the fact that the primary removal mechanism is not a specific one.…”