A flexitank is essentially a large plastic bag, fitted with a loading and discharge valve. Prior to loading, the flexi-tank bag is laid out into a box container. Unlike the tank container, which is re-used repeatedly, the flexi-tank is designed for one trip. The empty contaminated bag must be disposed in an approved waste facility. Certain materials can be incinerated and others might be suitable for shredding in preparation for re-cycling.
It has been reported that when fully laden the weight of the 24,000 litre bag causes the side wall of the box container to distort outwards beyond ISO. The side wall is designed to withstand a certain pay-load for static cargo. The flexi-tank load is liquid and the laden bag effectively forms the shape of the box. Cargo surge during movement and transport of the box results in potentially excessive side and end wall loads and potential instability during trucking and lifting.
Currently containers are tested and approved by issue of a safety certificate (CSC), however flexi-tanks are tested independently of the container. At present there are no regulations forcing manufactures to test the integrated package of bag and box, although trade associations have developed their own test programmes.
