Severn Trent Water (STW) is
reported to be saving around
£100,000 per year on energy
costs thanks to the installation of
ABB variable speed drives at its
Wanlip Sewage Treatment Works.

STW was suffering low flow rates
on its dry well flow pumps, with
typical rates being less than 400L/s
against a design of 550L/s. This
meant that under storm conditions
the works was unable to achieve the
rates specified under the
Environment Agency’s consents
without the need for supplementary
temporary pumping, adding to
operating costs.

To solve the problem Sentridge
Control, a member of the ABB
Drives Alliance suggested installing
75kW ABB industrial drives on all
the pumps, each equipped with ABB
Anti-Jam software, part of its
Intelligent Pump Control (IPC)
software.

The Anti-Jam software module
performs a number of cleaning
cycles every time the pump starts.

Each cycle consists of a series of
rapid ramp ups in both forward and
reverse directions and removes the
debris from around the pump
volute, preventing it from entering
the pump and blocking it.