Abstract: A study was carried out to determine about the rapid sand filter which are very commonly used in Conventional water treatment plants. The rapid sand filter beds are suffering by the problems like Mud ball formation, unsatisfactory effluent, etc. Dual media and multimedia filters can overcome the limitations of RSF. Capping of crushed coconut shell is used as a Dual Media. Designing Dual media filter capped with crushed coconut shell proves to be more efficient, economical and durable. The sample was collected from nearby lake which was highly turbid and having high amount of total solids. A fabricated model was prepared having dimensions 0.5 x 0.5 x 0.9m. Gravel, Sand, Coconut Shell was filled in the model in the layer of size 20cm, 15cm, and 20cm respectively. The tests which are conducted on the sample are pH, Turbidity, BOD and Total solids. It improves the performance of filter in the terms of high filtration rate, high turbidity removal and high decrease in percentage of total solids and thus making it more applicable. This filter media reduces about 90% of turbidity. The amount of total solids was decreased about 89%.

Keywords: Rapid Sand Filter, Coconut Shell, Filtration, Turbidity, pH, BOD, Total Solids.

| DOI: 10.17148/IARJSET.2022.94101