Canadian miner Nautilus Minerals announced in December 2008 that the construction of the equipment for the Solwara 1 mining sytem has been deferred, with various contracts awarded for the construction of the mining system either being terminated or delayed. This system includes a subsea slurry lift pump (SSLP).
Nautilus CEO Stephen Rogers announced: “Given market conditions, the board of directors and management have undertaken a
thorough review of all operations. Directors and management require greater certainty
that all elements needed to progress the project to completion are in place before making major equipment expenditures.”
The Solwara 1 production system comprises a mining system made up of a mining support vessel (MSV), a sea-floor mining-tool (SMT), and a riser and lifting system (RALS). The SSLP is an element of the RALS.
Nautilus awarded American oil and gas company GE Hydril the contract to supply the SSLP for the Solwara 1 marine mining project.
Orders for elements of the mining system, the RALS and the SMT, have been deferred.
Rogers says that deferring the equipment build for the mining system is a difficult, yet appropriate, decision to preserve a strong cash position, which stood at $266,6-million in September 2008.
Nautilus said that in order to preserve this cash position, contracts and purchase orders would be suspended depending on how critical they were to the company’s revised development programme.
The $125-million contract for the construction of the mining support vessel, awarded to Norway’s North Sea Shipping, is in the process of being terminated.
In addition, Nautilus is reducing its workforce by 30%. Rogers believes these necessary actions will maintain a strong balance sheet needed to resume construction.
Rogers states, however, that the company remains committed to its aim of developing the world’s first sea-floor massive sulphide recovery operation and will be positioned to promptly restart the equipment construction.
Permitting work will continue for the Solwara 1 project, as well as engineering and testing. But the company has revised its devel-
opment plan, and no longer expects to begin production by late 2010.
The Solwara 1 project is located off the coast of Papua New Guinea (PNG). Nautilus
applied for a mining licence from the PNG government and production is set to start in 2010.
The company awarded key contracts for this mining production system in 2008.
UK-based company Soil Machine Dyn-amics was awarded the contract for the
design and production of the SMT, in December 2007.
Engineering, procurement and construction management (EPCM) provider Technip USA was awarded the RALS contract in April 2008. Specific equipment orders have been done under the Technip EPCM contract to GE Hydril for the SSLP, to oil and gas company GE Vetco Gray for the riser pipes, and to manufacturer Le Tourneau for riser handling equipment.
The riser handling equipment includes the derrick tower, draw works and surface pumps. This equipment will be integrated on board the vessel to form the RALS.
In June 2008, North Sea Shipping Holdings was awarded the contract for providing specialist MSVs.
When Construction Resumes
When the turn of events comes about and equipment build can continue, the marine mining world will encounter the world’s first deep-water mining system.
Nautilus states that the first step in the extraction process involves cutting the seafloor material and drawing it into the suction mouth of the SMT as slurry. This slurry is then transported to a pumping module (the SSLP) and lifted up a steel riser pipe to the MSV on the surface, where the material is dewatered.
After dewatering, the ore is transferred to barges on a continuous cycle for shipment to a nearby port facility.
The SSLP is a key design element of the RALS. The RALS is a deep-water lifting system. The RALS comprises subsea slurry pumps, a riser pipe, the riser handling system and associated deck equipment, all necessary to bring the slurry containing the ore to the surface.
The SSLP is a dual-module quintuplex pump. Each module is a five-chamber pump. In addition, the SSLP has few moving parts and incorporates redundancy with a multiple chamber design.
Nautilus is pioneering the concept of mining the sea floor off the coast of PNG for copper, gold, zinc and silver.
The company continues to explore for high-grade polymetallic sea-floor massive sulphide (SMS) deposits in 1 600 m of water within the western Pacific ocean’s ‘Rim of Fire.’
Nautilus confirms that studies have shown conventional flotation processing of Solwara 1
ore could produce a clean and high-grade copper concentrate, with grades of better than 28% copper, and copper recoveries of more than 85%.
In the third quarter of 2008, Nautilus submitted appropriate documents such as an
environmental-impact assessment and a mining licence application, to the PNG government. PNG registered the receipt of the mining lease application, which Rogers deemed a “milestone event.”
Potential of the Project
The sea contains over two-thirds of the world’s mineral resources. The sea also covers
71% of the globe. The Pacific Ocean is a particularly potential mineral-rich area owing to the fact that it alone covers a larger area than the sum of all the continents. It has specific
geological features in its western reaches.
Moreover, there are several benefits to
marine mining as opposed to mining on land. Nautilus lists five advantages to sea-floor mining: reduced mining infrastructure, limited
social disturbance, decreased overburden of stripping, reduced mining waste and
increased worker safety.
However, the project may be contested owing to the perceived detrimental effect of deep-sea mining. It has been reported that challenges looming for SMS-mining include convincing the public that environmental
issues are adequately tackled.
Other mining companies that have ventured into the marine mining industry include London-listed Neptune Minerals.
© 2009 - Mining Weekly