Research Papers

Displaying 11 - 20 of 89
Projects aiming to improve health cannot be just technology-driven, or the technology will under perform. Field situations are complex, and a holistic approach must be taken.
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.
CAUTION: This experiment has significant problems. We do not recommend this paper as a reference. The authors theorize that maximum grain size is not a significant parameter in biosand filtration. They found that using SODIS after BSF improved bacterial reductions.
Intermittent versus continuous operation of biosand filters.; Young-Rojanschi, C.; Madramootoo, C., 2014
Although BSFs (which are operated intermittently) effectively remove bacteria and viruses, they are not as effective as conventional slow sand filters which are operated continuously.
Biosand filters operated with one, two, or three day residence periods did not have statistically significant differences in E. coli removal.
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.