Slurry pump supplier Metso has secured a contract with Vale Mozambique to provide its Moatize coal mine with 110 heavy-duty slurry pumps.

The contract also covers initial start-up and commissioning, together with service training and assistance for the first six months of operation. The pumps are specially designed for the demanding conditions associated with arduous coal mining conditions.

Vale began production at Moatize in August 2011 and has ongoing expansions to increase production to 5 Mt in 2013, and then 11 Mt, with a final target of 22 Mtpa, the timing of which depends on the upgrading of the Sena railway, which is used to transport the coal from the mine to the harbour of Nacala.

“This pump contract with Vale is a good example of Metso’s global project handling capabilities, utilising our experts based in South Africa, Portugal and Brazil. As the biggest single pump order ever received in South Africa, this represents a real breakthrough for Metso in Mozambique,” says Graham van Bosch, regional sales manager: Slurry Handling Solutions, Metso South Africa. All 110 pumps will be delivered by the last quarter of 2013.

The Moatize delivery consists of heavy and extra-heavy duty horizontal and vertical spindle spillage pumps specifically designed and sized for the given applications, most of which are considered as arduous.

High chrome iron alloy is the material best suited for coal applications, providing excellent abrasion resistance with a good corrosion resistance. This material has proven itself time and time again at a variety of coal mines throughout the world with enormous success.

The most aggressive duty for the Moatize order, as with all mines, is the cyclone feed pumps where the Metso XM400 pump has been selected. This extra-heavy duty design was specifically chosen because of its large diameter impeller, which enables the pump to operate at a minimum rpm, reducing impeller tip speed, and hence rate of wear. The inlet diameter is such that the inlet velocity is also at a minimum reducing both abrasion and impact wear. Wet end life is therefore considerably extended.

All pumps chosen for this project are designed for ease of maintenance, during normal and routine inspection or repair. Bearing frames and rotating elements can be removed as a unit enabling efficient impeller and gland seal component renewal.