Research Papers

Displaying 11 - 20 of 90
Effects of physical disturbances on media and performance of household-scale slow sand (BioSand) filters; Mahaffy, N.C.; Dickson, S.; Cantwell, R.E.; Lucier, K.; Schuster-Wallace, C.J., 2015
Sand compaction and reductions in flow rate occurred as a result of physical disturbances (side impacts and filter movement) to Hydraid biosand filters.
A multi-attribute decision-making approach to the selection of point-of-use water treatment; Pagsuyoin, S.A.; Santos, J.R.; Latayan, J.S.; Barajas, J.R., 2015
Reductions of E.coli, MS2 and PRD-1 increases as filtration rate declines. Biosand filters using crushed granite as the filtration media has superior virus reductions than using Accusand silica as the filtration media, only when the media is not backwashed. E. coli reduction did not differ significantly between the two types of filter media.
This study developed a low-cost and accurate method for field enumeration of Vibrio cholerae. Additionally, the removal efficiency of V. cholerae and coliform bacteria using biosand filtration was evaluated. Results indicate that coliform removal efficiency generally exceeded V. cholerae removal, thus highlighting the importance of conducting pathogen specific tests rather than relying completely on indicator organisms.
Investigation of the Effect of Grain Size, Flow Rate and Diffuser Design on the CAWST Biosand Filter Performance; Chan, C.C.V.; Neufeld, K.; Cusworth, D.; Gavrilovic, S.; Ngai, T., 2015
This study investigated the effect of grain size, hydraulic loading rate, batch residence time, and diffuser design on the performance of the CAWST biosand filter. Coarser grain size reduced bacterial removal efficiency. Longer residence time, on the other hand, improved bacteria removal. In terms of diffuser design, smaller holes and tighter spacing reduced bacterial removal efficiency.
Arsenic removal from drinking water by a household sand filter in Vietnam — Effect of filter usage practices on arsenic removal efficiency and microbiological water quality; Nitzsche, K.Sonja; Lan, V.Mai; Trang, P.Thi Kim; Viet, P.Hung; Berg, M.; Voegelin, A.; Planer-Friedrich, B.; Zahoransky, J.; üller, S.K.; Byrne, J.Martin; öder, C.; Behrens, S.; Kappler, A., 2015
Household sand filter in Northern Vietnam consistently reduces arsenic from groundwater by 95% irrespectively of usage practices and sand usage duration. The findings are probably transferable to other sand filters, such as the biosand filter, if similar groundwater compositions (e.g. iron:arsenic ratio >50, phosphate <2.5 mg/L), geological settings, well and sand filter properties exist.
MS2 Bacteriophage Reduction and Microbial Communities in Biosand Filters.; Wang, H.; Narihiro, T.; Straub, A.P.; Pugh, C.R.; Tamaki, H.; Moor, J.F.; Bradley, I.M.; Kamagata, Y.; Liu, W.T.; Nguyen, T.H., 2014
Virus removal in V10 BSFs was greater than 99.99% after only 43 days of operation. Important factors included length of residence time, filter depth, and filter ripening, with the schmutzdecke playing an important role. Diverse microbial communities were found throughout the filter depth.
Using a biosand filter project by DHAN Foundation in India as a case study, this computer model outlines how an NGO can choose effective programme implementation strategies to increase the adoption and consistent use of household water treatment technologies in consideration of complex system interactions, trade-offs, and counter-intuitive outcomes.