They are used for eliminating colour, taste and odour in water. They contain a media made up of active carbon. Organic materials are absorbed (by being held on the surface) and removed from water. Due to the porous structure of active carbon, all organic based pollutants and chloride in the water are disposed of. When all pores are full, active carbon which constitutes the media material has to be changed. Just as in the case of sand filters, carbon filters are divided into two groups; fleck controlled and surface piped. (pls refer to Sand filters)
SURFACE PIPING ACTIVATED CARBON FRP SYSTEMS