New flow meter measures methane in natural gas

FCI’s ST80 methane mas flow meter

A new thermal mass flow meter from Fluid Components International enables engineers and technicians to measure methane content and provides emissions data to meet emerging government environmental and reporting requirements.

The ST80 and ST80L mass flow meters enable use of the company’s Adaptive Sensor Technology (AST), which uses a robust, open and cleanable design with no moving parts to provide an ideal methane measurement in demanding industrial processes. In addition, their international approvals for Div.1/Zone 1 ensure safe installation in hazardous gas processing areas, FCI said.

This measuring technique combines, for the first time, both of the industry’s highly proven constant power and constant temperature thermal dispersion sensing technologies in the same instrument.

Complementing this new measurement drive technique are a choice of four different precision flow sensor element designs to ensure best installed performance, including FCI’s new wet gas solution. The Wet Gas MASSter sensor developed for the ST80 Series optimizes the sensor head design and installation to prevent condensation droplets, entrained moisture or rain from contacting the thermowells, which ensures steady, reliable measurement, FCI said.

The ST80 Series flow meters are suitable for pipe diameters from 1 to 99 inches (25 to 2500 mm) and air/gas temperatures up to 850°F (454°C). They feature accuracy of ±1% of reading, ±0.5% of full scale and repeatability of ±0.5% of reading with flow rates as low as 0.25 up to 1000 SFPS (0.07 to 305 NMPS) and 100:1 turndown, the company said.

End users have an array of choices for this meter’s outputs and interface. It can interface with virtually any control system and/or set-up or configuration devices. Standard outputs include dual, NAMUR NE43 compliant 4-20 mA analog outputs, HART (version 7), Modbus 485 and a USB port, FCI said. Foundation Fieldbus or PROFIBUS PA or DP can be added. The optional backlit LCD display provides digital and bar graph readouts of the flow rate and temperature, totalized flow, alarms, diagnostics feedback and even a user defined label/tag field.

The ST80 series transmitter enclosure is NEMA 4X/IP67 rated, selectable for NPT or metric conduit port threading and is available in both aluminum and stainless steel. The transmitter cay be remotely located up to 1000 feet (305 m) apart from the flow element. The instrument also carries an independent, third-party evaluated SIL compliance.

The ST80 series transmitter outputs can match any DCS, PLC, SCADA, reorder or alarm system. For local display, the ST80’s graphical backlit LCD can show flow rate, totalized flow and temperature, which are continuously displayed in both digital and bar graph presentations while alarms or diagnostic messages display as needed to alert operators, FCI said.

As a greenhouse gas, methane remains in the atmosphere for approximately nine to 15 years according to various U.S. and global government sources. CH4 is over 20 times more effective in trapping heat in the atmosphere than carbon dioxide (CO2) over a 100-year period and is emitted from a variety of natural and human-influenced sources.