Cost-saving solution

The Qdos 30 metering pump from Watson-Marlow Pumps Group is proving a success in Barrie, Canada, a city with a track record for the quality of its potable water supply.

Sodium silicate is used as a sequestering agent in the water. It used to be pumped by diaphragm pumps, but high maintenance costs meant an alternative was needed.

Ron Baumgart, lead hand for ground water supply within the Water Operations Branch of the Corporation of the City of Barrie, says sodium silicate tends to give a hard coating to the ball valves in diaphragm pumps, leading to clogging and expensive repairs. Also, he says silicate will dry up when the pumps stop, which can damage the diaphragm when pumping restarts.

A pre-production Qdos metering pump from Watson-Marlow was installed in one of Barrie's potable water stations in June 2011. This ran without maintenance until April '12.

In April a production version Qdos 30 with ReNu pumphead technology was installed. With no seals or valves in the flow path to clog, leak or corrode it has boosted flow performance from 0.1 to 500 ml/min at 7 bar.