Modelling the WWTP operations to identify optimal retrofit options
We used our wastewater systems modelling software, WEST, to develop a detailed model of the Bjergmarken WWTP. The model was calibrated using the WWTP’s historical data.
The WEST model virtually simulated and evaluated various retrofit options, thus avoiding interference with full-scale operation. Results from the assessment showed that converting the ARP into a SSH process could reduce the aeration energy consumption by more than 20%. Better still, model results indicated the SSH retrofit would have limited or no impact on treatment efficiency, effluent quality or require any additional chemical dosing.
Long-term reliability of the retrofit was tested in the model using historical data for the Bjergmarken WWTP’s highest loading period during the annual Roskilde Festival. Roskilde Festival is one of largest music festivals in Europe and the largest in Northern Europe. This music festival usually produces a 50% N load and +70% P load. The test results showed the SSH retrofit was a reliable option under these extreme conditions, as well as under cold temperature conditions.
Following the model’s results, FORS A/S converted the ARP to SSH in their Bjergmarken WWTP. Longitudinal data was collected before and after the SSH was implemented which confirmed the WEST model’s predictions.our