Statistics of Flow and the Scaling of Ceramic Water Filters

According to the World Health Organization (WHO), there was an increase in the number of people that have access to safe drinking water between 2006 and 2010. Such trends can be accounted for partly by the increasing usage of ceramic water filters that can remove microbial pathogens from water. However, the initial flow rates in such filters are often limited to ranges between 1 and 3 L= h. In this paper, six frustum-shaped ceramic water filters of the same clay: sawdust composition were tested. Each ceramic water filter was filled with water and allowed to filter 20 times. Each time, the flow rate and water level were measured for a consecutive 12 h. Permeability values were estimated for each run of the ceramic water filters. Statistical analysis was performed on flow rates (in the first hour), mean flow rates, and estimated permeability values. The flow rate values (in the first hour) for the six ceramic water filters were found to be between 1.4 and 3.0 L/h. An effective permeability was obtained for ceramic water filters with a range of microscale and nanoscale pore sizes. The statistical variations in the flow rates and effective permeabilities were elucidated along with the potency of a multiple ceramic water filter system for scale-up studies in serving communities that need portable water. (C) 2014 American Society of Civil Engineers.