Coal Age

JUN 2013

Coal Age Magazine - For more than 100 years, Coal Age has been the magazine that readers can trust for guidance and insight on this important industry.

Issue link:

Contents of this Issue


Page 45 of 67

diesel engines Fleet Operators Ready to Gas Up The natural gas production boom in North America and elsewhere has flared mining industry interest in switching mobile equipment to LNG power BY RUSS CARTER, WESTERN FIELD EDITOR In the era before off-road diesel engine emissions became a point of intense focus for regulatory agencies, fuel choices for large, production-fleet mining equipment were relatively simple for mine operators— mainly, "Do you have diesel, what does it cost, and when can you deliver?" Even after the U.S. Environmental Protection Agency's early off-road diesel emissions standards and their European Union counterparts came into effect in the mid-1990s, operators' fuel concerns remained largely the same—quantity, availability and price. Fuel cleanliness was mostly an interesting topic of discussion in maintenance-shop lunchrooms and fuel sulfur content wasn't an operational concern for highhorsepower mining engines until more than a decade after the adoption of the Tier 1 standard in North America. Although subsequent Tier 2 standards imposed drastically lower emissions levels than Tier 1 for CO, NOx and particulate matter on off-road engines larger than 750 hp (560 kW), this class of engines was exempted from the even more stringent Tier 3 standards that were applied to less powerful diesels starting in 2006. However, Tier 4 emissions-control standards for the high-horsepower offroad engines commonly used in mining changed the rules of the game significantly when they became effective in 2011, first as an "interim" set of standards, followed by final standards in 2015. Engine manufacturers, who had largely been able to meet Tier 1, 2 and 3 standards by applying internal engine tweaks, had to develop design strategies that would allow new diesels to meet Tier 4's extremely low emissions levels without creating disruptive installation, operational and cost-related issues for their OEM and end-user customers. The advanced engine technologies required for Tier 4 compliance, among other things, put a premium on fuel cleanliness and sulfur content. Dirty, contaminated diesel fuel severely shortens the service life of injectors and other extremely fine-tolerance engine components, while previously acceptable fuel sulfur content levels are detrimental to specific emissions-control 44 systems and components needed for Tier 4-level control. These developments raised the ante for mine operators who need a new haulage fleet to commission a mine, for example, or want to repower to gain the benefits offered by the latest generation of high-horsepower diesels—scenarios that now would be accompanied by the cost of buying, properly storing and filtering the ultra-low-sulfur diesel (ULSD) fuel required by Tier 4-compliant engines. Even in less-regulated countries that don't enforce tight emissions standards, diesel-fuel availability and quality control pose problems for fleet operators running Tier 3 or older diesels. Fuel sulfur content in some regions can be as high as 10,000 ppm, compared with levels of about 3,000 ppm that were formerly common in industrialized nations—and 15 ppm in today's ULSD—and these high sulfur levels can shorten the life of certain components. Maintaining proper storage conditions may be difficult, leading to several forms of contamination. In addition, the price of diesel can fluctuate wildly from unpredictable events, despite the government subsidies found in many developing nations. With fuel and lube costs typically accounting for 40% or more of a large surface mine's annual operating budget and many other operating costs currently on a steep upward climb, mine operators everywhere are anxious to find economical solutions for controlling fuel costs. Suppose there was a fuel, available in abundant quantities in many global regions, that offered cost savings of 50% or more over diesel, and allowed dual-fuel operation while maintaining current engine performance levels. Too good to be true? Not at all, say a growing contingent of highhorsepower engine builders jumping on the liquefied natural gas (LNG) bandwagon. Full Throttle on LNG Caterpillar was one of the first to publicize its intentions to go full-bore on LNG engine development for mobile applications. Joel Feucht, Caterpillar's director of gas engine strategy for the energy and power systems businesses, made the announcement during his keynote address at the HHP Summit 2012, a first-of-its-kind event that examined the economic and environmental benefits of using natural gas in high-horsepower applications. "We have decided to go all-in on [natural] gas," said Feucht. "We are going to invest because we see a global market long term. Large engines are going gas. It's not debatable; it's our conclusion." Feucht's remarks confirmed that Caterpillar will provide an LNG fuel option for engines across its many high-horsepower lines for mining, rail, construction and other applications. The company recently announced its first expected LNG-powered products will include large mining trucks and the locomotives produced by ElectroMotive Diesel (EMD), a unit of Caterpillar's Progress Rail Services. "There is huge economic incentive to move to natural gas," Feucht said, noting the price of oil and gas are going to stay disconnected for the foreseeable future, thereby creating an economic incentive to use natural gas in fuel-hungry high-horsepower applications. Current users of natural gas to power high-horsepower equipment are realizing a cost savings of 30% to 50%, and new technologies expanding access, particularly in North America, have contributed to the expanding availability and decreasing cost of natural gas. Erik Neandross, CEO of Gladstein, Neandross & Associates, which organized the High Horsepower Summit conference, estimates that a single mining truck could save about $500,000 annually by using LNG instead of diesel. Although the prospect of using natural gas to fuel their trucks has had long-term appeal for many mine operators, until recently it's been an "if you build it, will they come?" type of situation for engine builders. At the MINExpo 2012 trade show held recently in Las Vegas, a product line manager for one of the major engine suppliers described the quandary: "Miners are always looking to be the first to try out new technology, but the second to pay for it." June 2013

Articles in this issue

Links on this page

Archives of this issue

view archives of Coal Age - JUN 2013