Wisconsin facility adds new pumping technology to deal with clogs & inefficiency
The Fond du Lac (Wisc.) Regional Wastewater Treatment Facility treats the City of Fond du Lac’s wastewater, along with that of 18 neighboring entities; the water is then discharged to nearby Lake Winnebago. The city’s population is 45,000, but with neighboring communities included, the plant handles flow from about 75,000. The average hydraulic flow capacity is 9.84 mgd, with a peak flow of 50 mgd. On average, the facility, which is located at the south end of Lake Winnebago, treats about 7.5 mgd of wastewater.
Neighborhood wastewater collection systems are submersible and primarily gravity driven. Of the 17 pump lift stations, 11 are submersible, none of which use variable frequency drives. Overseeing the maintenance of these submersible stations as well as rising energy costs are two stiff challenges for Fond du Lac’s wastewater treatment facility.
In July 2015, Fond du Lac – under the guidance of Flygt engineers and overseen by city personnel – installed a Concertor pump system in a duplex pump station located at Wild Life Acres, replacing one of the old pumps (5-hp CP3102 pumps, each rated for 140 gpm). The first Concertor pump is the lead pump, and it is expected to handle all flows in normal operation.
Concertor is the world’s first wastewater pumping system with integrated intelligence. A system that makes use of advanced technology, Concertor combines a fully integrated control system with IE4 motor efficiency, patented adaptive impeller N-hydraulics and intelligent functionalities.
Concertor’s control system integrates a processor, software, sensors, power electronics, a synchronous electric motor and self-cleaning hydraulics into a submersible shell. This system delivers significant cost savings, a more precise level of motor control, reduced risk of clogging, substantial energy savings and comprehensive data reporting.
Concertor users are able to efficiently manage their assets. They are able to select from a variety of performance fields instead of being limited to a fixed performance curve, which allows for enhanced operational flexibility and reduced inventory requirements. The system’s adaptive technology automatically selects the duty points to optimize performance; onsite fine-tuning is also available without having to change the impeller.
Energy savings have the potential to be substantial, starting with the premium efficiency of IE4 motors. The system’s patented Energy Minimizer automatically optimizes performance to reduce energy costs while adaptive N-technology impellers deliver sustained efficiency. The Concertor pump is running at 3.3 hp – the original pump was running at about 4 hp. The new pump is using about 90 kWh/month.
The small cabinet and pre-engineered solution with a setup wizard simplifies design and startup. Customers can significantly reduce their total investment.
Since its installation, the Concertor pump has undergone more than 50 cleaning cycles – that is to say, the pump detected some kind of blockage and completed its cleaning cycle of reversing the pump rotation at a reduced speed, jogging back and forth until the blockage cleared. This results in a cleaner sump and no costly callouts. In addition, these cleaning cycles prevent buildup and potential clogs that would eventually have to be cleared manually – an unpleasant and unsafe situation. The pump acceleration and deceleration cycles are designed to limit the maximum torque so that the pump life will not be compromised. The pump cleaning cycle will often free a clog within minutes, but may continue for up to one hour, virtually guaranteeing the removal of all clogs in tough wastewater.
The City of Fond du Lac estimates energy savings at 20% at the Wild Life Acres lift station after installing the Concertor system. Bothersome, time-consuming and expensive cleaning callouts have also been reduced, as confirmed by a monitoring system tracking the lift station operation both before and after the introduction of Concertor.