Vale, one of the world’s leading mining companies, has signed a major contract with Metso to deliver 110 heavy duty slurry pumps (Fig.) to their Moatize coal mine in Mozambique. The order is part of Vale’s plan to increase the mine’s capacity to 11 million t. The value of the order is 3.3 million €. The pumps are specially designed for the demanding conditions associated with mining and for easy maintenance. The order also covers initial start-up and commissioning, together with service training and assistance for the first six months of operation. Metso’s delivery will be completed by Q4 2013. The Moatize coal mine is situated in the central part of the Tete province, where Vale started coal production at the mine in August 2011. Vale is planning on increasing the production in three phases: first to five million tonnes in 2013 and further to 11 million tonnes. The final target is 22 million t/y. The timing depends on the upgrading the Sena railway, used to transport the coal from the mine to the harbor of Nacala.
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 good corrosion resistance. At Moatize, the most aggressive duty pumps are the cyclone feed pumps where the Metso XM400 pump was selected. This extra heavy duty design was specifically chosen because of its large diameter impeller, which enables the pump to operate at minimum rpm, reducing impeller tip speed and hence rate of wear. The inlet diameter allows minimum inlet velocity 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.