June 2017
PASTE
An INTERNATIONAL MINING Supplement
TAILINGS MANAGEMENT
The picture featured on the front cover shows two of three 128 m diameter FLSmidth tailings thickeners which recover around 9,600 m 3 / h of water for internal recycling at Los Pelambres, Chile www. flsmidth. com
International Mining 2 Claridge Court, Lower Kings Road Berkhamsted, Herts. HP4 2AF, UK Tel: + 44( 0) 1442 870 829 Fax + 44( 0) 1442 870 617
WORLD TAILS
Mineral sands tailings
For long distance tailings transports, MHWirth offers a full line of high-pressure slurry pumps covering every type of slurry application. Since the operational start-up of the KZN Sands Fairbreeze mine in South Africa in 2016, three Wirth™ triplex single-acting piston diaphragm pumps( TPM) from MHWirth have been transporting heavy minerals tailings via a 6 km long pipeline to a new tailings dam.
Two Wirth™ slurry pumps have already been performing well at the adjacent Hillendale mine for more than 15 years. Carl Erasmus, Project Engineering Manager at Tronox explains:“ Not only did they prove maximum reliability during that time, but they even showed very good performance rates beyond their original service life and were in excellent shape. In close cooperation with MHWirth we refurbished the existing pumps and complemented those by a new, stronger model to meet the increased capacity requirements.”
The new Wirth™ TPM has a capacity of 620 m ³/ h at 80 bar discharge pressure. It is eqipped with MHWirth’ s pump monitoring system( WPMS™) for real-time monitoring of key pump
www. im-mining. com
PASTE
TAILINGS MANAGEMENT
An INTERNATIONAL MINING supplement
IFC
P1
P4
IM looks at news from around the world relevant to paste, backfill and conventional tailings Knight Piésold’ s Bryan Ulrich and Jeff Coffin discuss tailings facility design and operation using filtered tailings BASF and ProProcess on how continuous, modular polymer hydration systems can be designed to remove the complexity in tailings thickening
P7 Ray Martinson of Paterson & Cooke Chile discusses how steeper slopes in a TSF are dependent on the right distribution system
P8 Jerold Johnson and Antonio Accioly of WesTech Engineering, Inc. discuss an improved feedwell design for thickening
P10 Andre Egger and Jürgen Hahn of BOKELA discuss high performance disc filters in tailings
P12 Robert Bradley of Golder Associates Ltd describes the potential problems of underground booster paste pumps – and advocates mine designs that avoid the need for pumps
IBC Putzmeister outlines how its pumps have helped save resources at Europe ' s largest coal power station
The new Wirth™ TPM
performance indicators. WPMS™ enables preventive maintenance, decreases downtimes and increases the availability of the pump, resulting in lower cost of ownership.
Weir pumps at Siilinjärvi
Yara has operated the Siilinjärvi mine in Finland since 1979. Each year the mine produces around 1 Mt of apatite concentrate from 11 Mtpa ore, and is Western Europe’ s only phosphate mine. The concentrate is processed into phosphoric acid in Siilinjärvi and then further into fertilisers and feed phosphates in Yara’ s plants in Finland and Norway.
The tailings have to be deposited at the Siilinjärvi plant and the existing tailings storage facility( TSF) was reaching full capacity. Yara did an extensive study for future storage of tailings and decided to go for a thickened tailings solution. The tailings would be thickened to 68-72 % by weight in order to build a + 2 ° deposit, thereby sufficiently increasing the storage capacity.
In order to transport the tailings from the thickeners to the TSF, Weir Minerals supplied a complete pumping solution to Yara, comprising three GEHO ® TZPM 2000 pumps and Warman ® centrifugal pumps. In addition, Weir Minerals also supplied the required hydraulic actuated slurry valves, suction strainers, slurry instrumentation and developed the functional description for Yara’ s distributed control system( DCS).
The system is operated remotely from the DCS without any programmable local control( PLC) devices, to enable future unmanned, automated operation. Local control can be established through tablets which are connected to the DCS, and the DCS provides diagnostic performance reviews of the pump and plant operation.
The system was successfully commissioned in February 2017, with slurry solids concentrations reaching planned targets, resulting in a slope at the TSF of approximately + 3 °. Weir Minerals continues to support and develop Yara’ s plant operation through local service support and training, ensuring plant optimisation is embedded into future operational development at the Siilinjärvi mine.