Brine Flow Measurement in a Geothermal Power Plant
Problem
Geothermal power plants harness hydrothermal resources containing both hot water (brine) and steam, with the steam driving turbines connected to electricity generators. Brine temperatures typically range from 140°C to 200°C depending on the well. A separator divides the two streams: steam flows on to the turbines, while the brine feeds the plant’s heat exchangers. Accurately measuring geothermal brine flow is essential to well efficiency — it lets operators optimize flow rates and calculate the right dose of scale and corrosion inhibitor needed to sustain or improve well productivity, which in turn can boost well yield and overall power generation capacity. Seeing an opportunity to improve its brine flow measurement process, a South-Eastern European geothermal energy company turned to Panametrics.
Application
| Medium | Geothermal brine |
|---|---|
| Temperature | 170°C (338°F) |
| Pressure | 10 barg (145 psig) |
| Pipe | 12″ Sch 40 CS |
| Flow rate | 400 m³/h maximum (1.5 m/s) / 1,761 GPM (4.9 ft/s) |
Benefits:
- Easy to set up
- Easy to operate
- No process shutdown
- No downtime and no periodic maintenance or calibration needed
- Reliable
Challenge
The plant had previously relied on other flow measurement technologies to monitor brine, but differential-pressure and electromagnetic flow meters struggled under the harsh operating conditions: solid content caused erosion, and high temperatures took a toll on accuracy. Beyond the technical shortcomings, the customer was frustrated that repairing, refurbishing, or calibrating these meters required shutting the process down entirely, resulting in costly production losses during turnarounds.
Solution
To verify actual flow conditions, Panametrics carried out flow tests using the TransPort PT900 Portable Ultrasonic Flowmeter. Its built-in data logger let the team record and store readings from each well tested, while the battery-powered design meant flow rates could be confirmed at remote wellheads without any external power supply. Because the PT900 clamps onto the outside of the pipe, it could be installed quickly without interrupting the process — a feature the customer valued highly. Following a successful measurement campaign, the customer went on to install nine permanent AquaTrans AT600 flow meters fitted with high-temperature transducers. The plant now benefits from highly accurate, reliable flow measurement with zero downtime for calibration or unplanned repairs.
Source: Panametrics Application Note (panametrics.com) — © Panametrics LLC. Localized and adapted by INTECH CONTROL, official Panametrics representative in the Slovak Republic and Hungary.