The Danish municipality of Aalborg operates two wastewater treatment plants to serve the needs of its approximately 200,000 inhabitants. It is the third-largest municipality in the country, with a sophisticated overall policy for efficient, cost-effective wastewater treatment.

The Aalborg Vest plant processes approx. 19 million cubic metres of wastewater annually, and has a daily capacity of approx. 60,000 cubic metres.

As part of the sludge dewatering process, the plant uses two Alfa Laval G2-80 decanter centrifuges, both equipped with controls.

Octopus assistance

Octopus helps the staff at Aalborg Vest adjust the polymer dosage to correspond to the particular solids load at any given time, with the aid of an easy-to–use touch screen. The operator manually sets the polymer dosage needed for the sludge dewatering process to proceed effectively. The Octopus system records this set point and monitors any changes in solids load, based on feedback from the decanter unit.

Using the “Active polymer control” function, Octopus then supplies a quantity of polymer that is proportional to the amount of solids fed into the decanter centrifuge.