Until about 10 years ago, liquids being transported by container ships were mainly carried in 24,000 liter stainless steel tank containers or steel drums. Anything classified as hazardous still has to be carried this way, but recent years have seen increasing volumes of non-hazardous liquid cargoes moving to single-use flexitanks, which work on the principle of those wine boxes you can buy. The liquid is pumped into a collapsible polyethylene tank that fits into a standard 20-foot container. Non-hazardous bulk liquid cargoes – such as foodstuffs, base oils, edible oils, wine, glycerine, fruit juices, non-hazardous chemicals and latex – no longer have to be carried in bulk tanker ships, ISO tanks or drums.
LOVE THEM OR LOATHE THEM
Flexitanks cut out cleaning, storage and positioning costs, are sterile, recyclable, easy to load and discharge and, because they are light, are cheaper to freight. No wonder cargo owners have taken to them. Uptake has increased eightfold from 2001 and will top 300,000 loads this year. This is expected to reach half a million by 2014.
You’d expect the shipping lines to be happy too, because – from the handling point of view – a flexitank is just another container. But is it? The number of suppliers has expanded with demand and, not surprisingly, much of the manufacturing is now done in low-cost economies. As flexitank consultant Capt Gerrit Uitbeijerse points out, cranes and rough weather put a lot of stress on flexitanks: enough to make them leak, on occasions, and contaminate the ship. “If a 200 liter drum leaks, that is a nuisance: when a 24,000 liter flexitank goes, you run for your life!”
The design of dry freight containers is highly regulated; flexitanks are not, Gerrit points out. Shipping lines wanted a standard that could give them some reassurance and protection; until then some were responding with a surcharge, while others refuse to carry flexitanks at all.
Something had to be done: just three years ago Andrew Watson, a director of Braid Logistics which manufactures flexitanks as well as operating them for clients, got together with two shipping lines and another manufacturer/operator: this group, along with the Container Owners’ Association, formed the management implementation group for COA flexitanks.
THE RIGHT WAY DEFINED
As a result, the COA was able to publish its Recommended Code of Practice for the Manufacture of Flexitanks and Operation of Flexitank/Container Combinationson January 1 this year. “We had to have a code to enable the industry to continue to grow,” says Patrick Hicks, Secretary General of the COA, “but the CoP is a recommendation, not a regulation: it provides a set of manufacturing and testing criteria which assures users that if a flexitank meets the Code’s requirements and is loaded correctly into the container, it is unlikely to cause a problem.”
But shipping lines can’t know whether the flexitanks they carry meet the CoP standards unless there’s a certification scheme along the lines of an ISO. Certification would have to be given by one of the maritime standards agencies, like Lloyd’s Register or Bureau Veritas. “People who ship large tonnages by flexitank would like to be able to say they will only procure them from COA compliant manufacturers,” says Watson.
Rail impact testing is available at the TüV Süd facility in Görlitz, Germany. This simulates the deceleration when a ship meets a big wave. However, it will not be easy to implement a credible global testing and verification regime, given that most of the manufacturing is now done in the Far East. “To my knowledge we are still the only company to have had a flexitank successfully complete the TüV rail impact test without leaking,”says Andrew Tisi, Managing Director of Philton Polythene Converters (PPC), which manufactures flexitanks in Essex, with a joint venture in China too. “The Code of Practice will have a beneficial effect on the whole industry.”
COST VERSUS DEPENDABILITY
Responsible buyers will be ready to pay a little more to meet the Code, but cost cutting won’t go away until there’s a robust verification scheme, says Tisi. Right now PPC, which has invested heavily in testing equipment, can’t produce flexitanks fast enough to meet post-recession demand. “Still, the future all depends on the shipping firms: they may decide to only accept verified COA flexitanks but until then there will always be people out there ready to undercut the market,” he adds.
To enforce the COA Code will mean price inflation, at a time when all the pressure is to cut costs. Though the shipping lines can refuse flexitanks, the final responsibility is the owners’, says Gerrit Uitbeijerse: “They should treat their wine, or whatever it is, with all the care a mother gives her child: it is going to get some rough handling so it surely deserves a decent cradle!”
FLEXITANK FACTS
•The lowest cost way to move liquids
•Easy to load and discharge
•Foldable – easy to store when empty
•Recyclable – most countries have polyethylene recycling facilities
•Always new – no risk of contamination