Fluid Components International”s Model ST51 mass flowmeter is designed for biogas production and methane capture and recovery systems. Packaged in an explosion-proof transmitter, the meter features a thermal mass, insertion-style flow element with flow accuracy to +/-1 percent of reading over a broad flow range from 0.3 to 400 SFPS (0.08 to 122 MPS), and repeatability of +/-0.5 percent of reading. The flow element is available for use in line sizes from two to 24 inches (51 to 610 mm) diameters. It operates over a wide turndown range of 100-to-1, which is essential due to the variable gas flows in wastewater treatment. It operates at temperatures from zero to 250 F (-18 C to 121 C) and withstands pressures up to 500 PSIG [34 bar (g)]. The new ST51’s robust thermal mass flow sensing element has no moving parts and no orifices to clog or foul to attain virtually maintenance-free service in wet, dirty biogas applications. It also includes built-in temperature compensation circuitry for accurate, repeatable measurement year-round as temperatures rise and fall seasonally. The flow element is constructed with a 316L stainless steel body and Hastelloy C-22 thermowell sensors to resist corrosion. It is approved for use in hazardous environments with approvals that include: FM and CSA/CRN.