SIPOS Sophisticated Actuation Aids Pump Station

Erie Non-Potable Water Pumping Station

The town of Erie, Colorado was in need of a new pump station to move treated water from its North Water Reclamation Facility storage reservoir to one of two locations. The required discharge process for the water was either via low-head pump to a high-head pump at Boulder Creek, or to the facility’s irrigation distribution system.

Re-using water normally discharged from waste-water treatment plants is a growing trend as it makes good use of a valuable resource, especially in dry climates such as Colorado. The most common destinations are non-potable uses, such as irrigation as precious potable water is saved for household and other domestic uses.

Pipestone Equipment was selected to provide valves for the project, which was designed by Burns & McDonnell and constructed by Jennison Construction. Included in the scope of supply were the isolation valves and air valves that are typically required for such systems. Technically significant for the North Water scheme was the combination of engineered pump control valves and a surge anticipation valve, designed to work together to minimise hydraulic transients and provide a long system life.

An optimised solution

Minimising hydraulic transients during both normal and emergency operating conditions will improve system longevity and reliability. To achieve this at the North Water facility, an optimised solution for pump control developed by Pipestone Equipment incorporates low headloss ValMatic ball valves controlled by electric actuators manufactured by SIPOS Aktorik. The SIPOS actuators for Erie were programmed to create a linear acceleration and deceleration of water during normal pump operation. Additionally, rapid closure during a loss of electrical power event via backup from an uninterruptible power supply is facilitated by the actuation technology.

The ability to programme SIPOS’ actuators to change speeds at any time during the valve stroke means that linear flow rate change can be obtained and, when implemented effectively to produce linear flow change, the SIPOS actuated ball valve will provide the minimum system transients possible for a pump control valve. Additionally, the actuator speed-time curve can be easily calibrated and adjusted in the field, as required, for fine tuning.

The emergency operating condition created by a loss of electrical power while operating the pump station at full flow rate requires additional analysis including creation of a hydraulic system model. Each system has unique characteristics which determine the magnitude of water hammer transients. Fine tuning of the operating time can be achieved via hydraulic model or field trials.

In summary, a combination of state-of-the-art-valves and programmable valve controls with accurate engineering calculations and modeling provide an optimised pump station design that promotes a long and trouble free system life. And, by minimising both normal and emergency transient magnitudes, piping system stresses are kept as low as reasonably possible.

Sipos Aktorik
Tel: 01275 871141
www.sipos.de

Published: 1st March 2012