Instrumentation plays a pivotal role in meeting state and federal regulations. To ensure compliance, the Lakehaven Utility District (LUD) in Washington state realized that it needed reliable flow meters for some of its most difficult applications -- the air and gas flow lines serving its aeration basins and anaerobic digesters.
Thermal dispersion flow meters are well accepted in the municipal industry to provide reliable flow measurement at low flows and low pressures. That's why LUD turned to the Magnetrol® Thermatel® Model TA2 thermal dispersion mass flow meter for its ease of use and ability to handle these difficult applications.
Having the new equipment in the aeration lines maintained a minimum flow rate to prevent the diffusers from getting plugged, while also being used in conjunction with dissolved oxygen probes to provide sufficient flow to meet the oxygen demands in the basin. On the digester gas lines, the units measured the amount of methane going to fuel the boiler to generate hot water/steam for the plant, as well as the excess methane going to flare.
The TA2 flow meter offers the ability to verify calibration in the field, a capability that reduces process downtime and saves on the cost of factory recalibration. A two-step procedure of high- and low-flow validation tests allows the user to verify that the device's response to flow, near the two extremes of the calibration curve, has not changed since the original calibration.
Additional features of the TA2 include:
- Dual gas calibration with two unique curves (for air and digester gas, for example)
- Field adjustability to install in different gas types or adjust for different gas mixes
- Internal resettable and non-resettable totalizers
The TA2 also features a strong signal at low flows and low pressures with high turndown, and its calibrations are ISO 17025 and NIST traceable.
Magnetrol is an exhibitor at WEFTEC.15 and can be found at Booth 2339. For more information, visit www.magnetrol.com.
