DNV qualifies new GTT technology

The containment system has been further developed to reduce the boil-off rate from LNG carriers by one third – from 0.15% to 0.20% of the cargo volume per day.

Common practice has been to build LNG carriers with boil off rates of 0.15% of the cargo volume per day, reflecting the typical need for boil-off gas as fuel on board.

These improvements have been achieved by increasing the containment tanks’ insulation thickness from 270 to 400mm, this effects the design of system elements that penetrate the insulation, such as the lower pump tower support and gas dome. It also has an effect on the loading system of the secondary barrier. The new system also implements GTT’s modified liquid dome design.

So far, 27 vessels with the new Mark III FLEX system have been ordered by Korean shipyards – twenty of which will be built to DNV class.

GTT is developing another LNG containment system, NO 96, which is being developed to meet similar boil-off requirements will also undergo DNV qualification.