Traveling Bridge Sand Filtration

The AquaABF is designed to filter water and backwash cells simultaneously during normal operation. By design, the filter bed is divided horizontally into 8 in. or 12 in. (20.3 or 30.5 cm) wide cells.

• Inlet water floods the sand bed through multiple inlet ports via gravity and flows through the granular media and porous plate.
• Filtrate passes through the effluent backwash port and into the effluent channel.
• Backwashing occurs under the hood, which is suspended below the traveling carriage. During backwash, the carriage and attached hood move slowly across the filter bed. This action consecutively isolates and backwashes each individual cell. Cells not under the hood continue the filtering process as the hood and carriage travel across the AquaABF filter bed.
• A backwash pump draws filtered water from the effluent chamber and backwashes each cell by pumping water back through the effluent port. Another pump picks up the washwater, which has collected in the hood and discharges it to the washwater trough.
• The backwash cycle occurs only when needed because of headloss, or if desired, by a pre-selected time cycle.

The Turbilite® option collects the post-backwash filtrate and re-directs it to the washwater collection system. The system minimizes post-backwash breakthrough, maximizing turbidity and suspended solids removal; and reducing virus and other microorganisms often present in potable water and wastewater.