Fluid Components International (FCI) offers the new Model ST51 Mass Flow Meter for use in biogas production and methane capture and recovery systems. The explosion-proof Model ST51 is ideal for these applications, as it is safe, easy to install and requires virtually no maintenance.
“This flow meter is designed specifically to solve the unique challenges to flow metering in bioprocess-generated methane,” said Randy Brown, FCI’s Marketing Manager. “The ST51 is the optimum biogas flow meter solution at an affordable price. It features a no-moving parts design that’s non-clogging and operates over a wide flow range with low flow sensitivity. It’s packaged in an explosion-proof transmitter, and the calibration is matched to the user’s actual gas composition and installation conditions.”
In biogas produced by an anaerobic digester, the measurement of gas flow is complicated by the composition of the biogas, which is primarily methane and carbon dioxide, with smaller percentages of hydrogen sulfide and other gases. The wetness of the gas and the presence of hydrogen sulfide and other particulates create a corrosive condensate that is deposited on the pipe wall and on instruments in the pipe. Furthermore, the gas flow varies widely, based on fluctuating plant process demands and seasonal variations in temperature and humidity.
The Model ST51 Flow Meter features a thermal mass, insertion-style flow element with accuracy within ±1% and repeatability within ±0.5% over a flow range from 0.3 to 400 ft/s, The flow element is available for use in line sizes from 2 to 24 in. dia. Accommodating the highly variable gas flows in wastewater treatment, the ST51 has a wide turndown range of 100:1. It operates at temperatures of -18–121°C and withstands pressures up to 500 psig.
The unit’s thermal mass flow-sensing element has no moving parts or orifices to clog or foul for virtually maintenance-free service in wet, dirty biogas applications. Built-in temperature-compensation circuitry ensures accurate, repeatable measurement year-round with seasonal temperature variations. The flow element is constructed with a 316L-stainless-steel body and Hastelloy C-22 thermowell sensors to resist corrosion. It is designed for use in hazardous environments, with approvals that include: FM, CSA/CRN, Class 1, Div 1, Groups B, C, D; Class 1, Div II, Groups A-D, ATEX Zone 1, II 2 G Ex d IIC T6–T3, II 2 D Ex tD A21 IP67 T90°C–T300°C.
For ease of use and applications flexibility, the ST51 Flow Meter provides various outputs for user interfaces and information. Dual 4-20mA analog outputs are user assignable to flow rate and/or temperature, and there is a 0-1 kHz pulse output for totalized flow. The transmitter’s digital communications include an RS-232C port. For units that include the integral digital display option for reading flow and temperature, there is a wireless IR link for PDA use.
Applications that are difficult to access can be accommodated with a remote-mount configuration that can be installed up to 50 ft away from the flow element. The remote mount and integral transmitters are each housed in an aluminum enclosure that is NEMA 4X approved and meets IP67 requirements for protection from water and dust ingress. The ST51 is available with Input power options of either 18–36 Vd.c. or 85–265 Va.c.
Fluid Components International, San Marcos, Calif.
Hall 10.1, Stand D28