TENOVA Delkor has completed the supply of six thickeners and three horizontal belt filters to Masan Resources’ Nui Phao project in Vietnam, a contract that included two of the largest free standing steel thickener tanks in the world. The scope of the contract covered the design, manufacture, supply and commissioning of six elevated steel thickener tanks of diameters ranging from 6 metres up to 60 metres, as well as three horizontal belt filters.
Three contracts were awarded for the different plant areas during 2011 and 2012, with commissioning completed in July 2013 and plant operation commencing in August 2013.
Nui Phao, which came into production in 2013, is the world’s largest producer of tungsten outside China. When fully operational, the mine will also be one of the largest single point producers of bismuth and acid-grade fluorspar in the world.
The 60 metre and 55 metre diameter thickeners installed were unique in that Tenova Delkor supplied elevated steel tanks as opposed to the in-ground concrete designs that are typically used for thickeners of 50 metres or greater diameter. The elevated steel tank design was chosen as it reduced the overall plant footprint and installation time.
Apart from designing a tank capable of holding more than 20,000 tonnes of slurry, Tenova Delkor successfully met a number of other design challenges, including meeting the client’s request for clear access to the underflow cone by removing support columns. The support structure also had to be designed to minimize loading so that civil contractors could build the concrete foundation. This required a number of design iterations until the design suited all parties. Another important requirement was for the tank to withstand the local seismic conditions.
The mine is 100km from Hanoi with limited local industry, which also posed some logistical challenges. Despite the challenges, Tenova Delkor completed commissioning of the tanks less than 18 months from receipt of the order.
With the successful commissioning of the Nui Phao mine, Masan Resources began to contribute to the financial statements of the Masan Group in March. It reported sales of VND440 billion and EBITDA of VND56 billion in March. With the mine ramp-up gathering pace, enhanced EBITDA contribution from the resources business will progressively reflect in the group’s financial statements.
Masan says all four Nui Phao products were sold in March, and the plant throughput operated at an average of 89.7% of design capacity levels. The focus is now on improving recovery rates across products in order to achieve higher sales volumes.
Sales of tungsten value added products are well under way, with product being sold to customers under long-term contracts across Europe, North America and Asia. The JV with HC Starck, international leaders in tungsten processing, is progressing well and is enabling Masan Resources to access state-of-the-art technology for deep processing of tungsten.