In high-head wastewater pumping applications that result from long force mains or high-static heads from hilly terrains, lift station design engineers typically select oversized pumps that sufficiently overcome the inherent friction losses. However, a dramatic reduction in efficiency occurs at the pump operates far from its best efficiency point. In these situations, the use of vacuum-primed pumps arranged in series can achieve higher pumping efficiencies and lower resulting power costs.

“Series” pumps are connected with the outlet of the first pump leading into the inlet of the second pump. Working in concert, the flow rate remains the same while the heads produced by the two pumps are combined. Even by adding the second pump, the total connected horsepower and resulting power consumption is still less than larger and higher head pumping units as the series connected vacuum-primed pumps operate closer to their best efficiency point. Factor in maintenance savings from the smaller, lower-horsepower motors and total life-cycle cost highly favors the series arrangement.

Read more about the “series” pumping concept and how consulting engineers and wastewater collection system managers can solve the unique challenge of high-head force main while also saving on energy costs - download the white paper here