The transport of bulk liquids can be much safer. At least that is what Dr Erik Eenkhoorn thinks. He has developed a system for securing liquid loads. Inflatable components prevent tanker trucks from tipping over and also reduce fuel consumption. Eenkhoorn recently obtained his PhD with his findings from the University of Twente.
Many accidents still happen with tankers at the moment. And according to the PhD student, this is partly due to current legislation. There are strict rules for securing a solid load, but not for transporting liquids in tankers: 'If the load consists of cans of oil, you have to pack them in boxes and secure them with foil and straps. This prevents the cargo from moving while driving. But transporting 20,000 litres of oil in a 40,000-litre tank is done without proper securing, causing the liquid cargo to sloshing in the tank. With all the possible consequences.'
Bad solution
By law, tanker trucks carrying hazardous liquids, such as oil, must have sling baffles with holes. The baffles slow the forward movement of the load when braking. A poor solution, Eenkhoorn's doctoral research shows. 'The baffles do not provide lateral stability, so the risk of overturning in bends or emergency situations remains high. Moreover, the baffles are not mandatory for, say, manure or milk. This research shows that the dynamic behaviour of any liquid in a tanker is dangerous as long as you don't secure the load properly.'
Cairbag
Eenkhoorn, owner of a company in research and development of innovative products, spent ten years researching an alternative to sling baffles. The result is an inflatable system (Cairbag), a kind of air bag made of rubber or TPU that is placed inside the tank. The dimensionally stable bag fills the empty space in the tank and traps the pressure of the bulk liquid, preventing the cargo from sloshing when moving. This has an additional advantage, according to Eenkhoorn. 'Because the cargo does not move while driving, you save 5 to 6 per cent of fuel. Sliding partitions, on the other hand, destroy energy and can lead to high fines because of the environmental damage they cause.'
The conclusion in Eenkhoorn's thesis is therefore clear: the existing legislation must be amended, otherwise the number of accidents involving overturned tanker trucks will not decrease any time soon. 'The same rules should apply to the transport of solid loads and bulk liquids. The mandatory use of sling baffles should be reconsidered. Such a change in the law requires scientific substantiation. That substantiation now exists with this study. The lobby towards government thus has a powerful instrument in its hands to realise this necessary change.'
By: Kelly Bakker
Source: University of Twente
