Research Papers

Displaying 61 - 70 of 89
The study by Chiew et al. criticizing the KAF had some experimental errors and may have suffered from experimental bias. The chemical and physical processes involved with zero-valent iron are complex.
Households with a BSF in this very rigorous study had 47% less diarrhoeal disease than control households.
Field Evaluation of Long-Term Performance and Use of Biosand Filters in Posoltega, Nicaragua; Vanderzwaag, J.C.; Atwater, J.W.; Bartlett, H.; Baker, D., 2009
Long-term performance of filters 3 and 8 years old was good, with 96% removal of E.coli, but due to poor construction only 10% of households were still using their BSFs.
Decentralized systems for potable water and the potential of membrane technology; Peter-Varbanets, M.; Zurbrügg, C.; Swartz, C.; Pronk, W., 2009
A comprehensive review of the potential of membrane technologies in HWTS.
A model of the cost-benefit ratios for various intervention options for reducing cholera found that digging a borehole, installing BSFs, or school-based vaccination programs are usually better than community-based vaccination programs.
More work is needed to optimize the Kanchan filter for arsenic removal. Water flows too quickly through the nail bed, so that no difference was found in influent arsenic levels and those in the filter standing head after flowing through the nails.
The authors of the Chiew et al. (2009) paper defend their methodology and results against criticisms. Differences between their results and others are likely due to water quality differences.
Children in households with a BSF had 54% less diarrhoea than in control households.
E. coli removal in slow sand filters is related to ripening time, temperature, biological activity, media grain size and empty bed contact time (related to flow rate and sand depth). The quantity of protists (a type of micro-organism) in the schmutzdecke was strongly associated with E. coli removal and may indicate predation as a key mechanism.
Week-by-week microscopy images of a biolayer developing in a slow sand filter are presented.