As global demand for clean energy continues to rise, liquefied natural gas (LNG) plays a vital role in powering economies across continents. At the heart of this massive energy exchange lies a crucial task—accurate and reliable custody transfer measurement. Whether LNG is stored in large land-based tanks or transported via carriers, precision LNG tank gauging systems are essential for ensuring contractual integrity, operational safety, and financial accountability.
Key Technologies in LNG Tank Gauging
1. Servo Tank Gauges (STG)
Servo gauges offer high-precision level measurement with resolution in the millimeter range. Equipped with density and temperature probes, they enable accurate stratified measurement of LNG layers within the tank.
2. Radar Level Gauges (GWR or FMCW)
Non-contact radar provides continuous and safe level monitoring, especially effective in cryogenic environments. Radar gauges are resistant to pressure, temperature, and vapor interference.
3. Multi-Spot Temperature Sensors
These probes measure temperature at multiple heights, capturing thermal stratification and aiding in accurate volume-to-mass conversion.
4. Tank Side Calculators and DCS Integration
Advanced systems integrate field data into a tank management system, which computes LNG mass, compensates for vapor space, and connects directly to enterprise resource planning (ERP) systems for reporting and billing.
Benefits of Accurate LNG Custody Transfer Gauging
✅ Financial Accuracy
Reduces billing disputes between trading partners and ensures compliance with contract terms.
✅ Regulatory Compliance
Meets international measurement standards such as OIML R85 and API MPMS Chapter 3.
✅ Operational Efficiency
Real-time data improves inventory control, loading/unloading accuracy, and asset utilization.
✅ Enhanced Safety
Remote, automated gauging reduces manual intervention and minimizes human error in cryogenic environments.
✅ Data Traceability
High-resolution data logs support audit trails and post-transfer verification.
Applications in the LNG Supply Chain
LNG Import/Export Terminals
For loading arms, tank farms, and jetty operations during vessel transfers.
Floating Storage and Regasification Units (FSRUs)
To manage complex loading and discharge cycles at sea.
LNG Carriers (LNGCs)
For monitoring cargo conditions during long-distance transportation.
Peak Shaving Plants and Storage Hubs
To accurately track send-out and refill operations.
As LNG continues to gain prominence in the global energy transition, accurate and trustworthy custody transfer measurement becomes more critical than ever. LNG tank gauging systems, with their blend of precision instruments and intelligent software, are the backbone of transparent, efficient, and safe LNG transactions.