More than just emissions monitoring: ALPHAMETER® 2.0 enables real-time quantification of biological activity
With the ALPHAMETER® 2.0, INVENT Umwelt- und Verfahrenstechnik AG introduces the next generation of its measurement and control system for biological wastewater treatment. The system records key process parameters in real time, thereby laying the foundation for direct, quantitative control of oxygen supply. Another new feature is the continuous monitoring and documentation of nitrous oxide (N₂O) emissions.
Understanding biology. Precisely controlling aeration.
Conventional aeration control systems are primarily based on dissolved oxygen (DO) readings. While these indicate the current oxygen content in the aeration tank, they allow only indirect inferences about the actual oxygen demand of the biological process and the current efficiency of oxygen transfer.
This is where the ALPHAMETER® 2.0 comes in: It continuously measures parameters from the gas and liquid phases and links these to the operating data as well as to the known pure-water performance of the aeration system. From this, key process parameters such as the oxygen uptake rate (OUR), oxygen utilization under operating conditions (αOTE), and the α-value are determined in real time.
This reveals what is actually happening in the biological process: how active the biological system is, how high its current oxygen demand is, and how efficiently the aeration system transfers oxygen under the respective process conditions. On this basis, the required air flow rate can be determined directly from the current oxygen demand and the actual oxygen transfer conditions. Instead of adjusting aeration only in response to a change in the DO value, the ALPHAMETER® 2.0 enables direct, quantitative, and demand-based oxygen control.
This reduces reliance on a purely reactive control logic and creates a significantly more precise basis for aeration. Changes in biological activity and influent load can be accounted for more quickly, and over-aeration can be avoided. At the same time, energy-saving potential becomes apparent and can be specifically harnessed.
Monitoring oxygen demand and oxygen transfer
The continuous measurement of OUR, αOTE, and α also provides valuable information for operation and plant optimization. Load profiles and changes in biological activity become visible, as do changes in oxygen transfer—for example, due to fouling, scaling, or aging of the aerators.
In this way, ALPHAMETER® 2.0 combines process monitoring and aeration optimization on a shared data platform—and lays the groundwork for predictive operations management and condition-based maintenance.
ALPHAMETER® 2.0 measures nitrous oxide emissions
With ALPHAMETER® 2.0, INVENT expands the system to include the measurement and documentation of nitrous oxide (N₂O) emissions from biological wastewater treatment. Nitrous oxide is a highly potent greenhouse gas that can be produced particularly in connection with biological nitrogen conversion processes. By combining gas analysis with the measured exhaust air volume, N₂O emissions can be quantitatively measured and documented over the course of the process.
This enables operators, for the first time, to view the development of biological activity, oxygen demand, oxygen transfer, and N₂O emissions collectively. As a result, correlations between process control, energy consumption, and emissions become more apparent.
Relevance in the age of UWWTD
With the new Urban Waste Water Treatment Directive (UWWTD), energy efficiency, greenhouse gas emissions, and data-driven operation of municipal wastewater treatment plants are coming into sharper focus. The ALPHAMETER® 2.0 supports this development with a unified database for process performance, energy consumption, and emissions: The continuous measurement of OUR and oxygen transfer lays the foundation for demand-based aeration and energy optimization. At the same time, N₂O monitoring enables quantitative documentation of nitrous oxide emissions.
The next generation of biological process control
With the ALPHAMETER® 2.0, INVENT combines biological process intelligence, direct aeration control, and emissions monitoring in a single system. Continuous measurement data is converted into immediately actionable information for operation and control.
