Most bulk material ports are relatively shallow, but the costs of dredging mean this is unlikely to change. Fortunately, there is now a solution to improve throughput without dredging – the Transmax.
The estimated majority of global export ports for bulk materials are geographically remote and not sufficiently dredged to handle modern bulk carriers.
Typically, iron ore is transported by 180,000 deadweight (dwt) capsize bulk carriers, which require 19 metres of water depth under the keel. However, Australian ports such as those at Port Hedland, Newcastle and Whyalla often don’t meet these requirements.
This is partially because dredging is very expensive, with costs increasing exponentially when dredging hard materials. Further, environmental requirements and regulations can present far-reaching challenges.
This is a major constraint for the development of ports’ throughput and economic growth, which is why mining materials handling supplier thyssenkrupp Industrial Solutions entered into a partnership with Australian-based infrastructure company National Ports Corporation to develop the Transmax.
Related stories:
- thyssenkrupp to deliver world’s largest rail mounted stackers and reclaimer for South Flank
- Roy Hill buys jaw gyratory crusher from thyssenkrupp
- New CEO for thyssenkrupp Mining Technologies
The Transmax is a self-unloading, super-shallow draft bulk carrier that aims to redefine transhipping operations in shallow water ports globally. The vessel opens draft limited ports around the world to far greater tonnages with no dredging, capital expenditure, or change to materials handling process or equipment.
It can traverse fully loaded, 24/7, into any limited draft port in the world, including Port Hedland, Newcastle and Whyalla, with cargo capacity far greater than existing industry capability for a given draft and unrestricted by tide limitations.
The Transmax is a 190,000 tonnes dwt on a 14-metre draft transhipment bulk carrier. Currently the existing capacity on the same draft is 120,000 dwt. thyssenkrupp Industrial Solutions has equipped it with cargo handling systems such as an on-board travelling ship-loader.
The Transmax is equipped with bow and stern thrusters to make the vessel highly manoeuvrable, and vacuum or magnetic mooring systems for fast mooring and unmooring.
The vessel can be loaded at berths using existing ship-loaders or can be loaded directly from a shore conveyor at the rate of up to 20,000 tonnes per hour, avoiding the capital cost for conventional marine berth and travelling ship-loader. This represents a substantial saving in capital expenditure.
It can also self-unload its cargo into any size ocean-going vessel, including the 400,000 dwt Valemax or at the port of destination at the rate of up to 13,000 tonnes per hour in a safe and environmentally-friendly manner.
When compared with prevailing technologies that have a maximum unloading rate of 5000 tonnes per hour, the Transmax outperforms by delivering a 260 per cent improvement on current unloading rates and 100 per cent for current loading rates.
Each self-propelled Transmax can be custom designed to the water depth available at each port. For example, a 61,000 dwt Transmax can transit a port with water depths of only 6.5 metres, a major improvement on existing capacities.
Franz-Maria Wolpers, Senior Executive in the Mining Technologies business unit of thyssenkrupp Industrial Solutions says the company is delighted to be helping its clients solve one of the most complex challenges when operating in shallow, restricted and remote ports.
“In addition to opening up access to those ports the new system dramatically increases self-unloading rates into any type of bulk carrier to the port of destination through a thyssenkrupp materials handling system,” Wolpers says.
“In cooperation with National Ports, we are thus offering mining companies and port operators worldwide significant efficiency improvements, including faster materials handling at lower cost and reduced environmental risk”.
thyssenkrupp has designed, built and guaranteed all material handling equipment installed on board the Transmax, including the on-board ship-loader.
Australian ports
The average vessel loading iron ore at Port Hedland has a deadweight of 180,000 tonnes on 18.2-metre draft, while Port Hedland’s inner harbour and the access channel has a water depth of 14.5 metres.
Laden capesize bulk carriers can only depart the Port Hedland harbour at high tide. The window of transit time for laden capesize vessels at Port Hedland is restricted by the tide and the shallow channel of 14.5 metres.
The average operating time available for laden capesize vessels to traverse the harbour and the channel is limited to about three hours every 12 hours.
As a result of tide limitations, large ocean-going bulk carriers often must depart the berth short loaded, representing an extra cost for mining companies. This means miners exporting iron ore out of Port Hedland are forced to depart at high tide.
As a result, the port authority has made the decision to let five to eight capesize vessels depart at the same time in a convoy. Should one of the cape-size vessels in the convoy break down while transiting the channel, it could create a major financial and environmental disaster (In 2016, 55 incidents were reported transiting the channel).
According to the Pilbara Ports Authority, the maximum throughput capacity of the port is 577 million tonnes per year. This could be increased by approximately 10 per cent by reducing the departure time between vessels, therefore increasing the number of vessels transiting the channel in convoy. Increasing the number of vessels transiting the channel in convoy will increase the risk of accidents.
In addition, with a number of new miners competing for limited slots on the tide, Port Hedland is expected to reach its maximum capacity in less than three years. Once the maximum capacity is reached, this will prevent the future growth to all the mining companies operating out of Port Hedland including BHP, FMG and Roy Hill.
A fit for purpose, fully-loaded 190,000 dwt Transmax can traverse the Port Hedland harbour and channel 24/7 unrestricted by tide limitations. By doing so, it would open the draft limited ports of Port Hedland to far greater tonnages with no dredging, no capital expenditure, nor change to materials handling process or equipment. This could double the maximum estimated throughput per year at the congested port of Port Hedland and would be a significant increase in revenue for the Pilbara Ports Authority and royalties payable to the State Government of Western Australia.