EC: Daniel 3818 LNG Ultrasonic Flow Meter

Process Control - Flowmeters: Daniel 3818 Liquid Ultrasonic Flow Meter provides stable, accurate and reliable dynamic volume measurement for liquefied natural gas. This is a Control Engineering 2014 Engineers’ Choice finalist.

By Control Engineering October 17, 2013

Emerson’s Daniel 3818 LNG Ultrasonic Meter addresses customer needs for not only improved accuracy in LNG custody transfer transactions and the ability to verify the contractually stipulated static tank measurements, but also the requirement for improved process management and plant efficiency. Specifically designed for reducing measurement uncertainty throughout the LNG value chain, this meter is ideal for many marine and offshore applications, including custody transfer, fiscal metering, line balancing, check metering, allocation measurement and tanker loading and unloading.

Measuring LNG volume dynamically using the Daniel 3818 Ultrasonic Meter delivers higher accuracy than static measurement methods and can result in real savings. The 3818 provides a factory-proven linearity within ±0.15% and a meter factor uncertainty of ± 0.027% due to its sophisticated multi-plane British Gas design, fast signal processing, and advanced transducer technology.

Tank level metering is, at best, close to ±0.5% accuracy. The 3818 measures the dynamic flow of LNG custody transfer on rundown and jetty lines, allowing producers and receivers to double-check measurements on ships’ gauges. An overall reduction of just 0.2% of measurement uncertainty by using the 3818 could equate to a $12,000 per hour reduction in financial risk. In addition, the 3818 allows access to real-time flow data, enabling plant operators to manage the LNG flow rate, thereby reducing the amount of hydrocarbon lost as Boil Off Gas (BOG). A 0.1% reduction of LNG lost to BOG as a result of lack of measurement process control could equate to $3 million per year.

With the increasing amounts of LNG traded in short-term (spot) contracts, there is a general consensus that dynamic measurement of product will be required, as is currently the case for custody transfer of oil shipments. In addition, LNG facilities are using shared storage tanks which require dynamic measurement to allocate ownership among multiple parties.

Emerson – Daniel Measurement and Control