IM 2020 July/August 20 | Page 42

MINING ENGINES The power transformation As more companies talk up the use of diesel-alternatives in the mining engines sector, one must ask: how long will the combustion engine last in this new ‘green’ environment? Dan Gleeson looks for an answer “While Cummins continues to invest in new sustainable technologies, diesel will remain a key power source for mining due to its power density, flexibility, durability and reliability. The goal is the lowest cost of production in the most sustainable way.” While this might be a quote from Robert Schaefer, Director of Mining Innovations & Growth Initiatives for Cummins Inc – a company that has, over the years, become known for its diesel combustion engines – it is a widely-held belief. For all the talk of battery-electric, hybrid, hydrogen and renewable power options for mobile mining applications, widespread adoption of a one-size-fits-all commercial solution is at least a few decades away. This is despite there being pockets of the industry where diesel alternatives are taking off: Battery-electric solutions are being trialled and acquired throughout the underground mining sector with leaders like Kirkland Lake Gold (Macassa) and Newmont (Borden) using them as core tenets of their environmental, social and governance (ESG) programs. Compact loading and haulage machines equipped with fuel cells are also being designed and developed for niche applications in underground mining. Hybrid battery and diesel-powered haulage solutions have been spoken of by Sandvik. These could be used in mines where significant uphill ramp infrastructure rules out the use of fully electric machines. On the surface, Anglo American is looking to trial hydrogen fuel cell technology on an ultraclass haul truck at its Mogalakwena mine in South Africa. This follows the building and startup of a 200-ton (181 t) hydrogen fuel-lithium battery mixed energy hybrid mining truck prototype by Weichai Power and CRRC Yongji. Trolley assist systems are also part of the open-pit mining mix, with Boliden’s Aitik trial and the planned commercial application of this technology at that mine and the Kevitsa operation being used as evidence that there is still a place for this hybrid solution many decades after it was introduced. There is no on-size-fits-all solution here. These examples show the dilemma the industry is facing and, hence, the reason Schaefer says there will “remain a place for efficient, connected, advanced diesel technology in mining for years to come”. Stage V/Tier 4 Final “These technologies, apart from Tier 4 Final, have not really caught on,” Scott Woodruff, Director of Mining + Oil & Gas at Rolls-Royce business unit Power Systems, told IM. As it stands, the major adoption theme in the mining engines market is Tier 4 Final in the US and Stage V in Europe. The engine hours for these ‘cleaner’ engines continue to rise as regulations for certain engine sizes in the two regions kick in/approach. All major engine OEMs associated with mining are supplying Tier 4 Final products, using diesel particulate-reducing technology or aftertreatment solutions to ensure emissions are in line with legislations. In Europe, the Stage V adoption has also Anglo American’s hydrogen fuel cell haul truck project, in South Africa, has seen companies from inside and outside the mining sector come together to achieve something new ramped up as legislation has come in, with Cummins, Volvo Penta and Rolls-Royce (with its MTU solutions) among the companies to have started supplying these engines. In November, Caterpillar ticked both US and EU directive boxes launching the latest and largest of its dual-certified EU Stage V/US Tier 4 Final engines, the Cat ® 3516E. The OEMs have been quick to start using these engines. Underground, Sandvik is rolling out Stage V compliant underground loaders and trucks for hard-rock mining applications following extensive testing. These have, to date, used Volvo Penta Stage V D16 engines such as the TAD1643VE-B. Similarly, GHH has announced the launch of a Stage V engine range in its load haul dumpers, starting with its 14-t payload vehicle. This comes on top of the release of several Stage V dump trucks and scalers. Christer Hedström, Director Product Planning for Volvo Penta Industrial, recently told IM: “We have several customers in the mining segment that are interested in the Stage V solutions. The Stage V D16 is based on the same engine as TAD1643VE-B and is now further improved with a dual stage turbo, common rail fuel equipment and a SCR (selective catalytic reduction) catalyst.” Woodruff sees these emission-reducing engines catching on outside of the countries and regions currently legislating for their use, as the added productivity and environmental benefits are appreciated in both open-pit and underground mines. The Series 1000–1500 MTU Stage V engines currently being used in Bell Equipment ADTs, for example, have been shown to reduce 40 International Mining | JULY/AUGUST 2020