Mechanical

Design Slow Sand Filtration Unit

There are various modifications which can be made to slow sand filters and these adaptations offer an affordable option to the household applications of using slow sand filtration technology to treating and disinfecting drinking water in both the rural and urban communities especially those in developing countries (Gottinger et al. 1). According to CAWST, an NGO in Canada, and the University of Victoria, Canada, a slow sand filter field survey carried out in Haiti on the effectiveness of slow sand filters in removing e-coli and other contaminants, as well as decreasing turbidity, was estimated for 107 filters which had been in an active use for an average period of 1 to 5 years (Blaker and Duke, 1). CAWST (Centre for Affordable Water and Sanitation Technology) assessed both the sustained use and user satisfaction through interviews in all the 107 households individually. The durability of the slow sand filter, its maintenance requirements, and its affordability was appraised by the users by recording various observations during the survey (O’Reilly, 28). In recent years, slow sand filtration has been assumed to be an old fashioned and inefficient method of treating water for both domestic and industrial use. This method has therefore been suppressed by other modern innovations and filtration techniques. However, under suitable circumstances, using slow sand filtration techniques may not only be simple and cheap but also the most efficient method of treating water. Slow sand filtration comes as an efficient method of any particulate suspended matter hence it is appropriate for treating (purifying) water that contains solids in suspension (Jonathan and Douglas, 7). Apart from Slow sand filtration, there are other methods of water filtration (Bourke, 19). These are. Rapid sand filtration, Pressure filtration, and Mechanical filtration. The advantages of using the slow sand method of filtration over other techniques have been proved practically over a long period of time. Moreover, certain industrialized cities, rural areas and also small communities recommend the use of sand filtration techniques as the method to use when purifying water and water supplies (Bourke, 19). The greatest advantage of using slow sand filtration over other filtration techniques is that it utilizes local skills and materials which are readily available in the third world and the developing countries and that it is more efficient in removing bacterial contamination (Jonathan and Douglas, 17). The systems also have very little maintenance and operational requirements which can be carried out by local personnel after the appropriate training. Although a slow sand filter is easy to operate and maintain, a highly skilled technician should be present during construction and design in order to ensure that it functions correctly. The main objective of this report is to design a slow sand filtration unit using activated carbon, fine sand, and gravel. The filtration unit will be capable of effectively removing pathogenic organisms, organic matter, as well as color and mild turbidity and therefore providing safe and clean water. The basic process of treating drinking water in order to increase its quality to the highest quality possible is as shown in the figure in the paper.

Back To Top