Southwark Council has embarked on a scheme to improve performance of the district heating systems serving its residential estates, working with the specialist water treatment company Environmental Treatment Concepts Ltd (ETC). Benefits range from more reliable heating and hot water supplies for tenants to a combination of major cost savings and fewer operational headaches for the council departments involved.
In the 1960s and 70s when large estates were built in Southwark to house London’s burgeoning post-war population, district heating was considered the best way to provide heating and hot water
to hundreds of flats. Unfortunately the impact of hard, London water on the district heating infrastructure was either not fully considered, or not seen as a potential problem in the economic climate of the time.
Over the years, however, limescale has been deposited in the water pipes and the heat exchangers serving the individual blocks of flats. This reduces the efficiency of the heating systems so that it costs the council more than it should to provide the services residents need. It also damages plant and equipment, leading to higher planned maintenance costs and more frequent break-downs.
However, the installation of Scalewatcher™ ENiGMA electronic water treatment
units is quite literally dissolving the problem. To the delight of heating manager Phil Barnes, an inspection just a few months after installing the initial units revealed that limescale had been removed from heat exchangers serving the Brimmington estate.
“The difference was dramatic as a badly ‘furred’ heat exchanger was made quite free of limescale within four months,” he said. “We liked the look of Scalewatcher™ ENiGMA from the specification we received from ETC
and it has certainly done everything we expected,” Phil added.
In total 33 units have now been installed on the Brimmington, Silverlock, New Place and Aylesbury estates and to serve residents in Ullswater Court, and the Pedworth sheltered housing scheme, at a cost of approximately £130k.
Unlike other water treatment systems
Scalewatcher™ ENiGMA relies on modern microprocessors and signal processing techniques. These work to remove existing limescale deposits within water heating systems and prevent new deposits. It can cope with pipes of up to a metre in diameter.
Treatment is necessary throughout much of the UK because about 70 per cent of the country has hard water
with naturally occurring calcium carbonate dissolved in it. When deposited in the form of limescale calcium carbonate narrows pipes, block showers and reduces thermal efficiency. There are also environmental costs linked to the higher fuel consumption necessary when water pipes are heavily ‘furred’ with limescale.