Problem: The engineers at a Midwestern wastewater treatment plant found that wet, sticky biogas was causing a corrosion issue affecting the flow sensors of their existing gas flow meters, leading to over-range and poor accuracy measurement issues. They believed a mixture of carbon dioxide, water and trace amounts of hydrogen sulfide were corroding the 316 stainless steel sensors. 

Solution: The applications team at FCI - Fluid Components International suggested that its ST100A Wet Gas MASSter Flow Meter with corrosion-resistant Hastelloy C-276 sensor tips would solve both problems. The shielded mechanical design of FCI’s wet gas sensor shunts water vapor away before it reaches the sensor and prevents any water vapor from collecting on the sensor head to avoid corrosion and any measurement accuracy or consistency issues. By shunting moisture, condensation and water droplets away from the ST100A’s thermal mass flow sensor, accurate gas flow measurement is maintained while minimizing errors that could occur from a cooling effect on the sensor that might cause a spike or false high reading.

Result: The flowmeters were installed in 2021 at the plant and have performed without issue since then. This meter can be calibrated to measure virtually any wet gas composition, and mixed, dirty and specialty gas. 800-854-1993; www.fluidcomponents.com