A water treatment plant operated by South East Water has reduced its maintenance costs by £2,000 a year and improved water quality, by replacing a motor with an industrial drive and motor from ABB.
The company’s Arlington pumping station takes water from a river and pumps it 3km to a treatment works, raising the water by 130m on the way.
Lyn Bevan, Electrical Engineer with South East Water, says: “We had a variable speed drive previously on this application, but it was an inductive system and did not give true variable speed, increasing the speed in steps. Also, it was becoming harder to find spare parts for it and maintenance costs to keep it running were increasing. The brush motor also needed maintenance, adding to our costs.”
Fitted as part of a complete M&E package by ABB Drives Alliance Partner MKE, the new application cuts maintenance cost by replacing the old equipment with a new variable speed drive and brushless motor.
The new drive allows the company to achieve a much finer control over the main pump in the station, meeting demand from the treatment works more accurately. Peak demand periods occur in the morning and early evening and the variable speed drive allows operators to ramp up the speed smoothly to take account of these peaks, transferring just the right amount of water to the treatment works to meet the demand. It also makes it easier to make better use of cheaper night time electricity tariffs, minimising operating costs.
“The project had a pretty tight schedule as the pump was the primary one for the pumping station and we could not afford to be without it for long, “says Bevan. The project, which took six weeks from concept to commissioning to complete, also involved MKE in designing, building and installing a platform to raise the new motor to the correct position so it could drive the pump, which was out of service for a total of ten days.
South East Water is currently replacing another drive on one of the smaller pumps and is using ABB for this as well.