KSB's Sewatec Pump: A Clean Way To Handle Dirty Jobs

KSB promotes the Sewatec dry-installed volute casing pump. Used for wastewater transport and treatment, sludge handling, and storm water applications, among other uses, the Sewatec pump features a flexible hydraulic design to meet a multitude of conditions. The pump offers superb reliability and lower maintenance costs, and it's easy on the environment, too.

Easy, low-cost inventory and maintenance
Pump ImpellerThe Sewatec dry pump line is a derivative of the KRT line of submersible pumps (also available from KSB). Because Sewatec's impellers, bearings, mechanical seals, O-rings and discharge covers are interchangeable with the KRT line, inventory streamlining is easy for customers that also use KRT wet well pumps.

The Sewatec line offers various impeller types that make it a virtual "non-clog" pump. Choosing the right impeller for the job helps prevent the clogging, jamming and locking that other pumps can be susceptible to. Because the pump is built to handle all types of wastewater, KSB offers a choice of four impeller types so that treatment plants can target the best combination for a specific application. For sludge applications, for example, the impellers can be chosen according to the dry-weight solids concentration as follows:

• For up to 5 percent, plants can use a multi-vane K impeller.
• For up to 6 percent, a single-vane E impeller is available.
• A free-flow (vortex) F impeller can handle concentrations of up to 8 percent.
• A diagonal single-vane (screw) D impeller is ready for concentrations of up to 13 percent.

Impellers are available in a variety of materials as well: cast iron, duplex stainless steel or wear-resistant shield cast iron.

PumpAll pumps are fitted with two independent mechanical seals with Silicon Carbide faces housed in an oversized oil chamber, providing long operation life and low maintenance costs. Oil changes are recommended only every three years or 10,000 hours of operation (whichever comes first). No external flushing is necessary. Pumps are supplied with non-proprietary mechanical seals (Burgmann) that helps keep the maintenance costs down. Alternative seals with covered springs for abrasive liquids are also available for all pump models. Mechanical seals are mounted directly over a stainless steel shaft which also contributes to a long, useful life of the pumps.

Small/medium pumps are supplied with bearings greased for life while larger units are fitted with bearings that can be externally regreased.

Environmentally friendly
Aside from helping wastewater plants save money through reliable operations and cost-effective maintenance and repair, the Sewatec pump line is good for the environment, too.

The oversized oil chamber contains non-toxic paraffin oil, making the pump ecologically friendly as well as long-lasting by providing reliable lubrication and cooling for the mechanical seals. Since this well proven design also used in the KRT submersible pumps does not require an external water source for seal flushing or cooling, the pump conserves clean water resources. The leak-proof design helps to prevent contamination by dirty liquids.

Reliability in a variety of conditions
Like the KRT pump, the Sewatec pump features two mechanical seals to protect against failure, even during long periods of use or fluctuating conditions. Even in the event the first mechanical seal fails, the pump bearings are still protected by the second seal. Since no external water flushing or recirculation of pumped liquid is needed, the mechanical seals can withstand dry-running conditions. This level of reliability is a hallmark of the Sewatec line, as is its flexibility.

Supported installation types include horizontal or vertical closed coupled when the pump is dubbed Sewabloc and horizontal flexible coupled, vertical flexible coupled, and vertical with cardan shafts. Customers should contact KSB for help selecting the best impeller and installation design for the job.

Discharge flanges meet ANSI standards. The pump line has a diameter range from 2 to 28 inches, a maximum flow rate of 15,000 gpm, heads up to 320 feet and a maximum liquid temperature limit of 158°F. Clean-out openings in pump volute are standard starting at 4-inch pumps.