Our Managing Director Stuart Ballantyne, gave an interview that outlines the latest capabilities and operations of STS design, transhipment vessels and services.
Excerpt from Australian Journal of Mining | July – August 2011
“Sea Transport has 20 years of experience in bulk feeders and self-dischargers. In 1991 Sea Transport designed the world’s first no ballast bulk carrier Deepwater … In 2008, the Sea Transport 5,200 dwt self-discharging barge Wunma [for MMG’s Century mine] was the only bulk carrier abandoned in a cyclone that actually survived.”
The transshipment system offered within Australia from Sea Transport has a comparably short lead time, Ballantyne states “a feeder barge you can get in 11 months” and it takes “up to 16 months” to build a floating harbour transshipper (FHT).
“The FHT comes in Handymax, Supramax and Capesize versions. The Handymax FHT has 30,000 tonnes of storage and capacity of 7mtpa; the Panamax size 50,000 tonnes storage and 12mtpa capacity; the Capesize 100,000 tonnes storage and 20mtpa.”
Like any transhipment system, the first contact with product is on land. Sea Transport Solutions uses a negative pressure shed, which is sized between 5-10,000 tonnes. A wet dock is attached, which includes patented stern loading vessels with capacities ranging from 3,000-6,000 tonnes. Loading vessels are shallow draft, which means the harbour required to house the terminal can be shallow with four metres depth.
Ballantyne described the loading process:
- 1) Feeder vessels, of 2,000 to 6,000 tonne capacity,
- 2) Back into the shed for loading;
- 3) Sail out to the FHT,
- 4) Return back into a reclaimer system inside it, which strips the feeders.
“If there is no bulk carrier alongside it stacks into the FHT. If the ship is there, the product goes directly from the feeder into the bulk carrier.” Sea Transport’s transhipper loads the bulk carrier with grabs.
“About 60% of the export cargo is actually sitting there, at the [FHT]… so the trick is to feed another 40% during the 3-4 day load out. That is how we optimise the size and number of feeders, so that these feeders go 24/7, backwards and forwards feeding just as a truck or a train would.”
– Stuart Ballantyne | Managing Director (STS)
Ballantyne explains that Sea Transport’s system can operate in seas that are often deemed too rough for transhipping. “10 days of model tests were carried out at the Australian Maritime College during November 2010 confirming that 4.5 metre significant wave heights can be handled without stopping the feeder vessel operations, whereas two metres is the normal maximum limit. The cost of a FHT and feeders and small shore shed works out about 20-25% of a fixed jetty installation. But the fixed installations now have to place a bond to have them removed at the end of the mine life, which could add 30% as a contingent liability.”
View the full article here.