Expanding this concept Samson have recently commissioned three of their new wheeled Material Feeders in a large mining operation in Southern Africa handling as mined rutile sands delivered by ADT achieving an average loading rate of around 1300 tons per hour per feeder. Based on the Berco “SALT” (Sealed And Lubricated Track) chains type D6 these feeders are able to operate reliably under extreme conditions handling highly abrasive ore.
Where the mine is close to the processor then this is the end of the external logistics story but in many operations there is a huge disconnect between miner and processor requiring complex logistic operations in between involving any combination of road, rail, barge and coastal or deep sea freight. Of course where the mine and processor are both either rail connected or close to suitable sidings haulage by rail is by for the better solution being both more economical and much less polluting with a very low carbon footprint. At the mine site railcars may be simply loaded using a silo and loading chute system mounted to a suitable supporting structure above the rails.
However many mine sites are not rail connected although there may be existing rail sidings close by. In this situation the mobile Samson Stormajor developed by Samson Materials Handling offers a unique solution allowing railcars to be loaded direct from road trucks at an existing rail siding without the need for fixed plant or infrastructure. Typically, a recent installation at Poznan, Poland, where Melafyr rock (similar to Basalt) is delivered to the Stormajor® by articulated dump trucks and loaded at a rail siding close to the mine.
The Stormajor® may equally be utilised for loading to barges for distribution on inland waterways, such an operation is on Lake Onega (Russia) where Gabbro rock is delivered to the lake side from the adjacent mine and loaded to barges of around 5000 DWT for distribution to Moscow and St. Petersburg.
The equipment operates on a simple berth using the long cantilevered outloading boom of the Stormajor to load the barges moored just off shore in deeper water thus avoiding costly dredging and an expensive permanent concrete dock. Samson has pioneered the concept of direct loading from truck to railcar, ship or barge.
Of course for deep sea shipment the concept is similar but larger equipment is required to load larger vessels: two examples are covered herein showing a project in Peru handling copper and gold concentrate and another project in Liberia handling iron ore.
In Peru the Goldfields Company operate from an existing port jetty and receives material direct from tipping trucks coming from the Cerro Corona Mine situated in the highest part of the Andes in northern Peru. The project involves the production of gold and copper by conventional open pit mining methods, and the copper-gold flotation concentrate is trucked to the Port of Salaverry for shipment to smelters in Japan, Korea and Europe. In this operation the concentrate is transferred direct from truck to ship using an integrated Samson style feeder mounted to the Shiploader chassis as a single and fully integrated one piece machine.
In Liberia, Arcelor Mittal mine iron ore in country close to Yekepa town which is transferred by rail some 280 km down to the port at Buchanan. In the port the ore, mainly fines, is extracted from the railcars by excavator and stockpiled in a covered storage for export on Panamax vessels. Samson supplied a mobile shiploader including twin mobile tracked Material feeders offering a loading rate in excess of 2000 tons per hour, limited only by the wheeled loaders. Using a combination of mobile equipment such as in Buchanan offers a relatively fast track and economical solution to start exporting ore with the minimum of fixed port equipment or infrastructure. Such equipment offers a long term solution for exporters or, thanks to the equipment inherent residual value, an effective answer for short term situations or pending installation of a permanent rail mounted alternative.
Similarly at the port of entry mobile discharge equipment, based often today on grab fitted mobile harbour cranes, is the preferred solution allowing the berth to be used for multiple cargoes including bulk, container and break-bulk. However, for bulk discharge of dusty cargoes due consideration must be given to environmental pollution from wind-blown fugitive dust created by material falling free from the grab. Free falling material separates into particles and dust is free in the air within the material stream, dust released in this way is readily disturbed by air movement including side winds. The only solution to control the dust is to control the material free fall into a suitable hopper. However, as the material falls from grab into the receiving hopper air is displaced which collects the free dust particles and the dust laden air is ejected from the hopper at high speed. The same problem applies to the loading of the tipping trucks where again air is displaced and any uncontrolled dust is ejected from the truck body. If uncontrolled combining both the dust generation from the grab discharge and from the truck loading is a double whammy and the result will be billowing clouds of dust from the discharge operation causing considerable pollution and being a hazard to the health of all working in the vicinity.
