Assessment of Up-Flow and Down-Flow Dual Media Filters for Secondary Treated Wastewater

The present research study has investigated the effectiveness of vertically down-flow and up-flow dual media filters in secondary treated domestic wastewater. Dual media filters, incorporating gravel, sand, and granular activated carbon, have been designed to overcome the challenges of tertiary wastewater treatment, such as the removal of fine suspended solids, microbial contaminants, odors, and nutrients. The up-flow dual media filter has achieved higher removal efficiencies for suspended solids and organic matter, resulting in effluent that meets discharge standards. Specifically, the up-flow configuration has enhanced contact time between the wastewater and the filter media, thereby improving the adsorption and filtration processes. Additionally, up-flow filter has exhibited reduced clogging issues and lower operational and maintenance requirements, as accumulated contaminants tend to settle at the bottom, facilitating ease in removal as compared to down-flow dual media filter.