Biomethane Measurement for Feed-in Monitoring

Feed-in of upgraded biomethane into the natural gas grid is subject to strict quality requirements: methane content must reach defined thresholds, while impurities such as H₂S, CO₂, O₂, siloxanes and other trace gases must comply with stringent limit values. Insufficient gas quality can lead to rejection at the transfer station and jeopardize the economic operation of the plant. Biomethane measurement technology from Fresenius Instruments ensures seamless quality control.

The Biomethane TDLAS is at the core of our feed-in measurement technology: as a laser analyzer based on TDLAS technology (Tuneable Diode Laser Absorption Spectroscopy), it achieves measurement accuracies in the ppb range (parts per billion) – a sensitivity not achievable with conventional NDIR analyzers. This precision is critical for trace analysis of sulfur compounds and other impurities whose limit values for grid feed-in are extremely low.

The GA220 Biomethane simultaneously monitors the main components of the upgraded biogas: CH₄, CO₂, O₂ and H₂S are continuously measured using NDIR and paramagnetic sensors. The combination of TDLAS trace analysis and GA220 main component measurement creates a complete biomethane monitoring system that maps all relevant parameters in real time.

Both systems operate with patented automatic zero-point correction without test gas – an economic advantage that significantly reduces ongoing costs, especially for unattended feed-in plants. The Cloud Connect Kit completes the solution: measurement data and alarms are transmitted in real time via mobile network, allowing operators of multiple feed-in plants to centrally monitor all locations and respond immediately when limit values are exceeded.