Using AI, new digital tool monitors LNG membrane tanks to increase uptime

Rough weather at sea can cause sloshing inside LNG tanks, creating high loads on the containment system. Now, a new AI-enhanced digital tools aims to help shipowners assess these sloshing impacts on LNG membrane tanks, to create alternative inspection plans to increase vessel utilisation and reduce downtime.

GTT reported it had received an approval-in-principle (AiP) from Lloyd’s Register in January for the digital solution, which is based on the French cryogenic engineering company’s Sloshing Virtual Sensor. Using a tank digital twin and real-time operational data sourced from LNG carriers, the digital solution monitors critical parameters and their respective impact on tank integrity inside the ships.
Combined with an appropriate risk analysis, the Virtual Sloshing Sensor-based solution can support Alternative Survey Plans aimed at optimising tank maintenance by extending the period between tank surveys, while complying with strict safety standards. This will translate into increased operational flexibility and substantial cost savings for shipowners and charterers, points out GTT.

 “This AiP is an important milestone in the validation of this cutting-edge digital technology,” said GTT chairman and chief executive Philippe Berterottière. “Artificial intelligence combined with GTT’s LNG core expertise has made it possible to develop this unique solution to help shipowners and charterers reduce their operational costs without compromising vessel safety,” he added.

“This software will improve overall safety at sea whilst helping reduce costs”

Lloyd’s Register global gas segment director, Panos Mitrou, said the digital solution would extend the time between tank entries. “This innovative software will provide LNG operators the opportunity to improve overall safety at sea whilst helping them to reduce cost and stay competitive in the global shipping industry and increasing fleet availability in a challenging energy landscape,” he said.

Milestone order in China

After a strong 2022 which saw a record number of LNG carriers ordered, 2023 is shaping up to be just as busy for LNG shipping and GTT, despite the company’s recent announcement it was exiting its Russian business to align with international sanctions. Notably for GTT,  it reported receiving on 3 January an order from China’s Hudong-Zhonghua Shipbuilding to design membrane tanks for six 174,000-m³ LNG carriers.

Constructed for Asian shipowners, the LNG carriers, with deliveries between Q3 2027 and Q4 2028, will be fitted with GTT’s NO96 Super+ membrane containment technology.

NO96 Super+ is based on the well-proven NO96 containment system, incorporating its double Invar metallic membranes and the mechanical anchors fixing the insulation panels to the hull. Hudong-Zhonghua broke ground for an invar production facility on site in January, with commissioning expected in July 2023.

NO96 Super+ offers the advantage of reducing the heat ingress inside the tank by integrating insulating Reinforced Polyurethane Foam (R-PUF) panels instead of plywood boxes. GTT said thermal performance of the membrane containment system is improved by incorporating glass wool joints, which are inserted between adjacent foam panels.

As a result, GTT guarantees shipowners can achieve an impressive daily boil off rate of 0.085% of volume with the NO96 Super+ membrane containment system, for the current standard size 174,000 m³ LNGC.