Hydraulic Ram Pump Application in Urban Water Distribution Systems

This study presents the potential of hydraulic ram pumps in managing excess pressure and reducing energy costs in modern water distribution systems (WDSs). A hydraulic ram pump (or Hydram for short) is a cyclic water pump powered by hydropower, generally used to pump drinking and irrigation water in mountainous and rural areas having short of power. This study introduces Hydrams as a low-cost alternative solution in addition to the more conventional pressure reducing valves (PRVs) approach for managing pressure zones in WDSs. Unlike PRVs, where the pressure is lost and not put into good use, Hydrams mitigate excess pressure at high-pressure zones and direct it to much-needed low-pressure zones. In addition, Hydrams require little maintenance, are cheap, simple, and environmentally friendly. The proposed system integrates a Hydram in parallel to the original centrifugal pump, where they can be operated interchangeably according to the system's hydraulics. Nevertheless, it is vital to correctly size the Hydram at the feed line and accompanying it with a storage tank at the low-pressure zone. The storage tank serves as a buffer between the intermittent water supply and consumer demand pattern. Moreover, the tank introduces flexibility into the system that allows more sustainable operating schedules. Two case study applications of increasing complexity are presented to demonstrate the potential of this approach. The Hydram and tank sizing is done by a simple heuristic approach, while the operation of the system is dictated by a genetic algorithm. The results demonstrate the potential of integrated Hydrams in reducing excess pressures and energy costs.