Continued need for maintenance, high costs, and eventual catastrophic pump failure are the reasons that Fayette County officials looked to seepex for a sludge transfer solution. The Town Branch Waste Water Treatment plant located near Lexington Kentucky is designed to treat wastewater generated from approximately 60% of Fayette County, serving a population of 130,000. The plant can treat a maximum flow of 64 MGD.
In the past, four piston pumps were used for sludge transfer. The eventual failure of the pumps was caused by excess pressures from operation and a lack of monitoring equipment. Piston pumps pulsate and run under high pressures. They have cylinder cavities which once evacuated need to recover/refill their pumping cylinders to continue flow. Even with two pistons running simultaneously, pulsation will persist. This pulsation requires high velocities/high pressure. The pumps eventually failed and operators stated that cleaning sludge from ceiling was the final straw, new technology was needed.
The solution came in the form of four seepex Smart Stator Technology Progressive Cavity BN 35-6LS pumps. The BN range is the basis to all seepex PC pumps. It is directly flanged-mounted to the drive, which makes a separate pump bearing obsolete. It is a compact and less expensive solution when compared to the previous piston pumps. The conveying capacity ranges from 0.13 GPM up to 2200 GPM with pressures of up to 720 psi. The 35 frame size designates a 20-100 USGPM. This combined with our 6LS rotor geometry and Smart Stator Technology (SST) is the perfect selection for sludge transfer.
SST consists of four stator segments and two stator halves. This construction allows for quick disassembly and maintenance of the pumps. Charlie Begley, Solids Process Supervisor at the water plant likes the design. “An SST equipped pump can be disassembled and reassembled in a fraction of a standard stator Progressive Cavity pump.” The stator segments also act as retensioning devices, letting you adjust the flow pressure of the pump by tightening a few bolts.
The pumps are also equipped with TSE temperature controllers, which prevent overheating by shutting the pump off if the temperature reaches unsafe levels.
The result was an integrated solution for pump maintenance and damage prevention. “Piston pumps have more moving parts than a progressive cavity pump, which means more can break. The Smart Stator Technology is going to make servicing these pumps much easier”, says Mike Smith, Maintenance Supervisor. “Replacement parts are much cheaper and down time is going to be a fraction of what it was before.”