A Duplex You’ll Actually Want

Lift station pumps in a duplex configuration.

Lift station engineering begins by understanding the water to be pumped and the goals of the customer. To Romtec Utilities, goals are usually described in technical terms such as peak flow, total dynamic head (TDH), and discharge elevation. These and other criteria are the first considerations in a lift station design-build project, but in order to meet these goals, engineering decisions about lift station sizing need to be made for an efficient, cost-effective, and long-lasting lift station design. An appropriate starting place when considering these factors of lift station engineering is the duplex lift station.
A duplex lift station is a technical term that describes a lift station design that specifies two pumps, but a pump station can have any number of pumps. A simplex station has one pump, a duplex has two, a triplex has three, and so forth to quadruplex and pentaplex. The reasons for selecting one configuration over another depend heavily on the customer’s pumping goals and the fact that pumps cost a tidy sum.
The duplex lift station offers several advantages that can benefit almost any lift station design. The first advantage is that a duplex lift station can be triggered by the lift station controls to alternate between pumps at the beginning of each pumping cycle. This allows the two pumps to share the workload and reduce wear on the parts and motors. Another advantage is the ability to meet variable flows. A duplex lift station can start both pumps when faced with high flow rates to prevent the wet well from overfilling.
In dealing with wastewater, it is especially important to include preventative measures in the lift station design to avoid overflow and possible public contamination. A duplex lift station can run with one pump for an extended period while the other pump is serviced, either for routine maintenance or because of clogging or binding. This means the wet well is in no danger of overfilling and spilling out wastewater even when one pump is decommissioned.
A triplex lift station retains all of the benefits of a duplex lift station, but it can handle much higher flow rates and can be serviced without dropping efficiency. Lift station sizing is an important part of lift station engineering because it is one of the best processes to ensure the customer’s pumping goals are met. The duplex lift station is one of the most common lift station design-build projects that Romtec Utilities sells. With benefits to efficiency, life-cycle, and safety, it’s no wonder customers love duplex lift stations.