“Our belt conveyors are able to solve complex problems with regard to the transport of any bulk material whether in the mining or cement industry,” says Christoph Dorra, regional sales manager South America, Conveying and Loading Systems, at BEUMER Group. “While the basic task to transport bulk material from the material feed up to the final discharge point seems to be comparable, on closer inspection no system is similar to the other. The spectrum of potential conveyed materials alone requires individual consideration of the components to be used with regard to wear resistance or the maximum permissible gradients of a conveyor.” In addition, the mass flow to be conveyed and the height to be overcome are the main factors determining the dimensioning of the drive unit of an overland conveyor. “A further challenge is posed by systems at high altitudes,” says Dorra. At altitudes exceeding 4000 m, as it is often the case in the South American Andes, for example, it must be considered that the air pressure and thus the density of the air decreases with increasing altitude. This reduces both the cooling effect and the insulating capacity of the air. As a consequence, the drive units like frequency converters and electric motors do not achieve the specified rated power that applies for installation heights up to max. 1000 m above mean sea level. This is the so-called derating factor.
In addition to the pure material specification and the mass to be conveyed over a certain height, the topography along the conveying route is of particular importance in the project planning.
The biggest challenge: the topography
“In 2009, we implemented an overland conveyor in China that is able to curve on 85 % of the 12.5 km long conveyor line between the quarry and the cement plant. The system literally winds its way to the destination, without any transfer point,” reports Dorra.
Potential obstacles appeared in the form of residential areas, roads and rivers that had to be crossed, larger bodies of water or mountains that could not be crossed. “Not everyone would automatically think of an overland conveyor as the optimal solution when faced with these challenges,” says Dorra. “But for us, these projects are a special attraction. Our target is to have as few transfer points as possible along the entire conveyor line.” This reduces both wear and tear and the environmental impact of dust, for example, but also increases the availability of the overall system and significantly improves ease of maintenance.
Four straight conveyors are converted to one BEUMER overland conveyor
A good example for such challenges is represented by the project of an American coal mine. Here, a BEUMER overland conveyor with a length of approx. 6.5 km conveys coal from a new underground mine portal to its main coal prepration plant. In the original request for quotation, the client requested four straight conveyors where three transfer towers would have been needed. For BEUMER Group, there was clear potential for optimisation here, of which the system provider was able to convince the customer.
The BEUMER team was also faced with exciting challenges in a Belgian project. Since the 1970s, the residues of a coal-fired power plant were landfilled on a fly ash stockpile. It was intended to transform the terrain into a nature park. In order to make this possible, the fly ash had to be conveyed to the Mass river, about two kilometres away, where it is loaded onto ships for further transport. These bring the fly ash downstream to an adjacent cement plant, where it is recycled as an aggregate.
The individually fitting system
How does the system provider manage to provide the appropriate solution for each of these applications? “We can draw on our comprehensive experience,” says Martin Rewer, team lead overland conveyor at BEUMER Group. BEUMER Group installed the first conveyor of this type with horizontal curves already in 1969; the first downhill conveyor with regenerative drive in 1980. Since the 1990s, BEUMER Group has also developed into one of the leading suppliers of Pipe Conveyors. In
Since the first overland conveyor with horizontal curves was constructed in 1969, components such as idlers, belts and drives have continued to develop. In addition, the systems are becoming larger and longer and the routes more complex. This resulted in the necessity to also constantly improve the calculation and the planning tools in order to not only withstand the requirements, but to even be one step ahead.
From the virtual toolbox
“In order to plan the conveyor for the individual application, we reach into our virtual tool box,” Rewer explains. “This way we can arrange the whole routing of the system and then discuss it with the customer as a 3D plan.” BOLT, the BEUMER Overland Layouting Tool developed specifically for this purpose, generates almost automatically a digital 3D model of the conveyor in the virtual landscape during the project planning. The required topography data are available in the public domain or are provided by the customer. Often drones are used. The aerial photographs include topographical information, which is then processed into digital terrain models.
“With this procedure we are able to considerably accelerate the project planning,” promises Christoph Dorra. “We have the possibility to provide the customer in advance with a concrete 3D project planning, which can be easily modified during the project life. This procedure allows us to tighten the time frame for the project.”
BEUMER Group GmbH & Co. KG, Beckum/Germany
The marketing expert studied economics in Bamberg. Before joining the BEUMER Group, she worked for leading companies in the intralogistics and capital goods industry as Global Marketing Communication Manager and Head of Marketing Communication and Public Relations.