IWA Publishing

Table 1

Summary of simulated scenarios for comparing performance of DO control, ABAC, and ABAC-SRT

Scenario	Airflow control	DO control	NH_x-N control	MLSS control	SRT control	Supervisory control
Case 1	- Airflow set point provided by DO controller for each zone	- DO set point of 2 mg/L in all zones	- Not used	- MLSS set point = 2,000 mg/L - WAS flow rate bounded between 100 and 3,500 m³/d	- Not used	- Not used
Case 2	- Airflow set point provided by DO controller for each zone	- DO set point provided by NH_x-N controller - Airflow set point bounded between minimum airflow for mixing and maximum airflow per diffuser	- NH_x-N set point = 1 mg/L - DO set point bounded between 0.5 and 2 mg/L	- MLSS set point = 2,000 mg/L - WAS flow rate bounded between 100 and 3,500 m³/d	- Not used	- Not used
Case 3	- Airflow set point provided by DO controller for each zone	- DO set point provided by NH_x-N controller - Airflow set point bounded between minimum airflow for mixing and maximum airflow per diffuser	- NH_x-N set point = 1 mg/L - DO set point bounded between 0.5 and 2 mg/L	- MLSS set point provided by SRT controller - WAS flow rate bounded between 100 and 3,500 m³/d	- SRT set point provided by supervisory controller - MLSS set point bounded between 1,000 and 3,500 mg/L	- Average DO set point of 1 mg/L - SRT set point bounded between 3 and 20 days

Scenario	Airflow control	DO control	NH_x-N control	MLSS control	SRT control	Supervisory control
Case 1	- Airflow set point provided by DO controller for each zone	- DO set point of 2 mg/L in all zones	- Not used	- MLSS set point = 2,000 mg/L - WAS flow rate bounded between 100 and 3,500 m³/d	- Not used	- Not used
Case 2	- Airflow set point provided by DO controller for each zone	- DO set point provided by NH_x-N controller - Airflow set point bounded between minimum airflow for mixing and maximum airflow per diffuser	- NH_x-N set point = 1 mg/L - DO set point bounded between 0.5 and 2 mg/L	- MLSS set point = 2,000 mg/L - WAS flow rate bounded between 100 and 3,500 m³/d	- Not used	- Not used
Case 3	- Airflow set point provided by DO controller for each zone	- DO set point provided by NH_x-N controller - Airflow set point bounded between minimum airflow for mixing and maximum airflow per diffuser	- NH_x-N set point = 1 mg/L - DO set point bounded between 0.5 and 2 mg/L	- MLSS set point provided by SRT controller - WAS flow rate bounded between 100 and 3,500 m³/d	- SRT set point provided by supervisory controller - MLSS set point bounded between 1,000 and 3,500 mg/L	- Average DO set point of 1 mg/L - SRT set point bounded between 3 and 20 days