Investment in energy and water needed in mining areas

Bernd Zehentbauer, senior vice president of mining technologies at Siemens VAI said, “Water shortages, rising energy costs and increasing social responsibilities in mining areas increasingly necessitate additional measures which affect profits. However, energy efficiency and water treatment technologies are helping to maintain competitiveness.”
He said that Siemens uses electric drives in trucks, shovels, conveyor systems and ore-crushing mills to reduce energy consumption and therefore ease the demands on power supply systems which are already very tight in many mining areas. Broadening the technology portfolio to include wastewater treatment is helping Siemens to ease the problem of water shortage.
“We use Manufacturing Execution Systems (MES) to analyse operating data along the production chain,” said Zehentbauer, “This not only creates transparency, but also helps management to make the right decisions that will lead to efficient and environmentally acceptable operations.”
Many mining areas are suffering from a growing shortage of energy. This is already affecting production in South Africa and Chile. Mines in northern Chile are reducing their power consumption to avoid the introduction of rationing. Zehentbauer said that, “the use of energy-efficient drive solutions is becoming more and more crucial to achieving sustainable production, and it also helps to save energy.”
Siemens has developed alternating-current drive systems for the heavy trucks that transport the material at opencast mines. They ensure that diesel engines run within their optimal speed ranges. Compared with conventional diesel drives, these diesel-electric drive systems not only have a lower environmental impact, but also save fuel and cut operating costs.
Gearless drive systems (GD) also help to reduce energy consumption. During the last 30 years, Siemens has been continually developing its GD systems, and has gained substantial experience with low-speed applications, such as grinding mill drives, mine winder drives, bucket chain excavators and drag chains.
Zehentbauer sees additional potential in combining belt conveyors and GD technology.
“Belt conveyors have proven to be a very efficient and cost-effective means of transporting bulk material in mining applications, irrespective of the distances, quantities and terrain involved. When it comes to energy efficiency and availability, gearless drives are a logical step in the further development of material handling systems.”
However, measures to reduce energy consumption have to take more than the individual systems into account. Zehentbauer said, “It is important to have a comprehensive energy management system.”
Apart from the energy issue, a shortage of water is preventing the expansion of production in many of the world's mining areas. Siemens' technical solutions for treating water, such as membrane systems, are helping to make better use of water, and thus ease the strain on the environment. The takeover of Industrial Process Machinery (IPM) - based in Manchester, New Hampshire, USA - has widened Siemens portfolio for dewatering raw material concentrates. Over 100 IPM high-performance filter presses are currently in use. Short press cycles and fast-moving filter plates ensure cost-effective operation. The press cakes they produce have such a low moisture content that there is no need for additional thermal drying plants. This considerably reduces energy consumption which, in turn, also lowers operating costs.
“The social challenges and environmental policy requirements regarding energy consumption and water supplies are imposing ever greater costs on opencast mining operations, and this calls for additional investments,” said Zehentbauer.