The AquaDiamond pile cloth media filtration system from Aqua-Aerobic Systems Inc. is designed to produce reuse-quality effluent with less maintenance than traditional sand media filters. With up to eight, diamond-shaped cloth media laterals, the gravity-flow system provides up to 2.5 times the flow capacity of a traveling bridge sand filter with an equivalent footprint.

The technology marries a traveling bridge filter with pile cloth media filter technology, says Robert Batek, P.E., senior applications engineer, filtration products. “In terms of solids, it can handle close to three times what granular media filters can,” he says. “The limit on that technology is 1.2 pounds per square foot per day, while the pile cloth media can handle up to 3.25 applied pounds of solids per square foot of media.

“The AquaDisk filters, with a vertical configuration and outside-in flow pattern, allow heavier solids to settle to the bottom of the filter tank. This inhibits some solids from ever contacting the media, saving power and prolonging media life due to low, on-demand backwashing. Furthermore, the outside-in flow pattern allows filtration to continue if unforeseen upsets occur. This is critical when extreme upset conditions occur that surpass the media hydraulic/solids loading rate.”

Using pile cloth instead of sand for filtration, the system requires less maintenance and has a media lifespan of about seven years. The fully submerged configuration maximizes filtration area. “You don’t need shovels anymore to remove sand,” Batek says. “And because it can handle so much more flow, you reduce the number of pumps and valves you would have with a traditional traveling bridge filter.”

The filter platform runs at 30 feet per minute. It has a roller-coaster design, enabling it to slide atop the basin, eliminating crabbing and possible derailment. The sand filter bridge is replaced by a platform that holds the pump, valves and programmable logic controller (PLC), making components easily accessible for maintenance.

Units can be custom fit to existing basins by adding or removing laterals. “The typical size of most of our operations is eight laterals,” Batek says. “But we also have a couple with six laterals. And our shortest installed unit to date is 36 feet long.” The fully automatic system has three modes of operation: filtering, backwashing and solids wasting.

During filtration, solids are deposited on the outside of the cloth media as influent wastewater flows through. The filtered effluent collects inside the diamond lateral and flows by gravity to discharge. The filtration process requires no moving parts. Headloss caused by the deposited solids automatically triggers backwashing.

During backwash, a pump vacuums solids from half the laterals as the platform travels the length of the unit. As the platform returns to the start position, the remaining laterals are backwashed. This arrangement means the unit doesn’t have to be taken offline.

Heavier solids that settle on the bottom of the tank are automatically pumped back to the headworks or other collection area during the solids wasting mode. 815/654-2501; www.aqua-aerobic.com.