STUDIES IN MULTIMEDIA FILTERS

Abstract

Water is one of the prime requirements for the sustenance of life in any form and is a basic need for humanity. The nature has provided water in abundance on the earths Although water is available in great quantities around us, all of it is no fit for drinking purposes. Continuous and adequate supply of wholesome water has been a basic requirement of the people from the days of civilization. Filtration is the oldest method of purifying water for drinking purposes. Water filtration for public water supplies was first introduced on a municipal scale in 1829 in England. Slow sand filters were thought to purify water in all respects. Later, when it was discovered that the bacterial quality of water from such filters was not satisfactory 9 the use of rapid sand filters started with the argument that when disinfection of water has to be done, then why not use filters which can give very high rates of filtration. With this philosophy in mind, the filtering media were modified from time to time to provide increased rates of filtration, without sacrifying the physical 2 quality o,f water. The development of dual and multi-media filters has proved to be a positive step in this direction,