Technology from Europe:
France/Belgium

LNG tanker employs hybrid, membrane cargo containment system

Armelle Danmanville, Gaztransport & Technigaz, Saint-Remy-les-Chevreuse, France 

Due for completion in 2004, the 74,000-cu-m Gaz de France Energy LNG tanker (constructed by Alstom's Marine Sector) will be the first LNG carrier to utilize the new CS1 membrane cargo containment system developed by Gaztransport & Technigaz (GTT). 

Upon its completion, the Gaz de France Energy LNG tanker will feature several technological “firsts,” including a new membrane system. (Photo courtesy of GTT.)

Membrane technology is an advanced means for LNG. The membrane technology benefits from more than 30 years of experience at sea onboard LNG carriers. Membrane systems are liners sustained by a ship's inner hull. The modular concept at the basis of the membrane technology allows for high flexibility, both in vessel sizes and in tank shapes. Hence, the design can be optimized to maximize cargo capacity and the profitability of transportation. 

The vessel will use the new CS1 membrane cargo containment system.

About 80% of LNG vessels ordered during the last several years use one of two membrane cargo containment systems available on the market – NO96 (Gaztransport) or MARK III (Technigaz). Both of these membrane technologies are composed of gas-tight barriers and insulation layers. The systems are sea-proven and highly efficient. 

While developing the CS1 concept, the idea has been to combine the previous technologies and retain their best features. Thus, CS1 technology is the combination of invar steel plates to form the gas-tight barriers (NO96 technology) and reinforced polyurethane foam to form the insulation layers (MARK III technology). Compared with previous solutions, this technology reduces the cryogenic insulation thickness by half. Accordingly, the ship's cargo capacity increases by 4,000 cu m.