The JetMix hydraulic mixing system from Siemens Water Technologies Corp. is designed to agitate slurries in digesters and sludge storage tanks as well as liquid streams with odd-sized tanks or channels.

The system is suitable for new installations, retrofits or upgrades. Its internal jetting action can deliver a mixing volume rating of up to 95 percent. Nozzles can be rotated 360 degrees from outside the tank for optimum digestion and maximum methane production.

“With the rotatable nozzle option we can do a very effective job mixing what would otherwise be considered hard-to-mix tanks,” says Marc Roehl, product manager, biosolids technologies. “Since the plant operator can come in and rotate the nozzles, you can get to those hard-to-mix areas and keep everything in suspension.”

The system’s external pump draws liquid solids off the bottom of the tank and sends slurry out the nozzle, while recirculating solids back through the pump. An optional top nozzle controls scum and grease as well as foam and other floatables.

The system can be used in small or large plants and enables operators to schedule mixing times. That can reduce power usage by 60 to 80 percent without decreasing gas production or negatively affecting volatile solids reduction, Roehl says. The modular design allows pumps and nozzles to be combined to meet load fluctuations and application needs.

“The way the system is designed, it’s very good for high solids concentrations – up to 6 to 8 percent and as high as 10 percent,” Roehl says. “In difficult mixing applications, like sludge storage tanks, where the tanks might be allowed to settle for months at a time, the system is very good at coming back online and re-suspending those solids in a relatively short time.”

Aside from typical pump maintenance, the system requires virtually no upkeep. Thorough mixing action saves on tank cleaning and washdown. “There are more than 300 installations in the field,” Roehl says. “The technology has a proven track record.” 866/926-8420; www.water.siemens.com.