Transport of bitumen products
Molten bitumen and related products are transported at high temperatures up to 250°C in independent tanks supported by means of special methods.
The bitumen/asphalt tanker RATHBOYNE has two independent cargo tank-blocks, each made up of four tanks with a total capacity of 5400m3. The cargo tanks exposed to temperatures of up to 250oC have been insulated with Rockwool. To accommodate the temperature differences and expansion/contraction associated with the transport of high-temperature liquids, the ship features a special system of tank support. This not only accommodates the high temperature differences but also alleviates energy loss through the plating. Tanks can expand in three directions without any adverse effect on the ship structure. To achieve this, the tanks have been mounted on a total of 516 steel supports welded to the hull into which multiple superimposed layers of various rubbers, have been sealed. The main purpose of the combination of rubbers is to absorb the heat generated, so that the maximum 250°C cargo temperature is reduced to an acceptable 80oC. Tank heating is performed by means of a thermal oil system.