- Software to control load-depending DO-level (based on actual NH4+-N), internal recirculation rate (based on NO3—N)
- Further process control for nitrification/ denitrification based on time signals of simple
- Over- and under-aeration can be prevented
- Energy costs go down and process stability increases
Depending on capacity and the relevant situation of each plant, individual design concepts are required for controlling the air supply. In addition, the investment cost as well as the available potential for energy savings plays a decisive role.
By combining the VACOMASS® system components you will be able to implement individual control concepts for regulation of the air supply including suitable control. This starts with simple installations to secure homogenous distribution, extending further to the implementation of a conventional oxygen control system, up to complex installations with local control of the air supply and suitably controlled pressure level of the blowers during aeration.
The model computing platform embedded in a control cabinet, collects the real-time concentrations of DO, NH4-N, NO3-N, pH and Redox in the biological reaction tank and provides the following key operating parameters for the process operation:
- DO set-points in different aeration control zones;
- Optimization of internal recirculation rate;
- Adaptation/ calculation of total aerated volume in the aeration zones;
No further support by lab data should be required for normal operation conditions.
The system real-timely monitors the aeration and water quality changes in the biological reaction tanks, thus reflect the activated sludge performance. The cabinet of VACOMASS® biocontrol is mounted in the central control room and provides the user visually operating results. It can also obtain through Profibus DP the relevant data of the wastewater treatment plant, and through model based calculation calculate the optimum control parameters (including the DO set-point and internal recirculation rate) for the biological reaction tank. These parameters can be transferred to the central control system using Profibus DP or other standard data transmission ways. The control frequency of the whole system can be done continuously.
In intermittendly aerated and controlled plants the effluent parameters can be improved with VACOMASS®biocontrol, the power consumption can be reduces and the processes of nitrification/ denitrification time phases can be controlled load-depending based on further process parameter like pH-value.
VACOMASS® biocontrol controls the processes of nitrification and denitrification in intermittently aerated tanks. Based on further actual process parameters like pH-value, dissolved ammonia/nitrate concentration in the aeration tanks it can be recognized, if nitrification process has almost finished and aeration can be interrupted. By switching the aeration off in time, over-aeration can be prevented and energy costs will be reduced. Furthermore the additional time can be used for denitrification which can then reduce nitrogen concentration in the effluent.
During start-up phase of the biological tanks the main control parameters and gain factors will be determined based on specific plant conditions. The system can contain required hardware and software components for external access via Ethernet or GSM/GPRS.