Turbo blowers provide more economic aeration in waste-water treatment plants

The secondary treatment stage at the Glenelg plant is a biological process which breaks down dissolved and suspended solids by using naturally occurring micro-organisms such as bacteria and protozoa. The process takes place in aeration into which air is blown to provide oxygen and mixing. This enables the micro-organisms to remove organic pollutants from the waste water.
Some 55 million litres of sewage daily enter the Glenelg waste-water treatment plant. The Exvel Bio turbo blowers supplied by ABB Fläkt are used for producing an air flow of totally 18 m3/s for the aeration basins in the secondary treatment of the sewage. The blowers run at a total discharge pressure of 60 kPa and a speed of 6,250 rpm. Power is provided by a 355 kW electric motor.
According to Maintenance Supervisor Brian Donnell at the Glenelg plant operated by United Water, the turbo blowers have proved to be an economic alternative to competing equipment such as ordinary compressors.
"Turbo blowers are efficient when a large amount of compressed air is needed for the aeration of basins with relatively low depths, which often is the case at waste-water treatment plants. I am particularly satisfied with the reliable operation of the total system," says Mr. Donnell.
The current range of ABB Fläkt's turbo blowers comprises single stage solutions from 3 000 to 100 000 m3/h with a pressure range up to six metre water levels. With two blowers in series the pressure range can be almost doubled. Blowers with a speed of up to 10,000 rpm are under development. This will enable higher pressure with single stage solutions for deeper basins.
Product Manager Kim Söderman at ABB Fläkt points out that all blower systems for aeration are tailored solutions composed of standard components, including ABB motors and, if required, frequency converters.
"The use of advanced blower selection software offers the customer individual blower solutions for almost every specific need. For each solution there will be one optimised selection utilising tested, standard and proven components," says Kim Söderman.
ABB Fläkt Oy Industrial Fans has been developing blowers since 1919, many thousands of which have been delivered world-wide. The company entered the aeration market in 1992, which can be considered as being in harmony with the whole ABB Group's increased concentration on products and technologies for the benefit of the environment.

For further information, please contact:
ABB Fläkt Oy Industrial Fans
P.O.Box 5
FIN-02621 ESPOO
Tel: +358 10 222 061,
Fax: +358 10 222 34 80