Research Papers

Displaying 41 - 50 of 89
Iron oxide amended biosand filters for virus removal; Bradley, I.; Straub, A.; Maraccini, P.; Markazi, S.; Nguyen, T.H., 2011
BSFs that were modified to have a layer of media where iron was mixed with the sand performed better than regular BSF at removing viruses. However, over a long time period (>200 days) even the regular filter reached 4 log 10 removal (99.99%).
Cluster Randomized Controlled Trial of the Plastic BioSand Water Filter in Cambodia; Stauber, C.E.; Printy, E.R.; McCarty, F.A.; Liang, K.R.; Sobsey, M.D., 2011
Households with a Hydraid BSF reported 59% less diarrhoea than households without. The BSF removed 93% of E. coli. 75-90% of households willingly paid $10 for their filter.
A quick overview of HWTS methods.
BSF's work best at removing bacteria and viruses when they have lower loading heads, lower maximum flow rates, finer sand, and longer pause periods.
A household-scale sand filter incorporating a biomass layer was developed and tested in the laboratory. Filters performed better with thicker biomass layers. Filter effectiveness increased up to day 30, and declined after day 75. (Not a BSF)
Small scale community and household approaches to water supply and treatment (Biosand filters, Ceramic filters, Chlorine, etc) each have their place in the provision of water to urban and peri-urban slums. Each has features making it appropriate in different settings.
A filter with coarser sand performed worse than one with finer sand, and a filter with a layer of iron filings in the media performed better than a regular filter.
Almost 1/3 of household water samples that had been filtered by biosand or ceramic filters had nitrite levels higher than the WHO acute exposure guideline. Although filters decreased E. coli, they did not consistently provide low risk water.
In a study in Nicaragua, 77% of filters were still in use after 12 months. The filters removed 80% of E. coli, but there was recontamination in the storage buckets so the overall improvement was only 48%.
Rational design of domestic biosand filters; Kubare, M.; Haarhoff, J., 2010
The most important part of biosand filter design is the careful selection of appropriate filter media (i.e effective grain size, uniformity coefficient, porosity).