LED Mine Lighting in Open Pit Mining Operations|
Article- April 2012 By Larson Electronics.com
Larson Electronics 600 Watt High Intensity LED Light Tower
When most people think of mining, they normally envision underground operations where coal and precious metals are extracted from the depths of the earth. While underground or tunnel mining is indeed a very common mining method, open pit mining is also quite common, and comprises the dominant form of mining for other less precious minerals and non fuel materials such as granite and limestone. Although surface and pit mining does not require the extraordinarily dangerous practice of tunneling hundreds of feet underground through thousands of tons of rock and earth, it is no less dangerous or difficult a process. While there is little danger of tunnel collapse and cave-ins with surface mining operations, many threats are still present in the form of wall collapses, heavy machinery in close proximity to workers, hazardous dusts, and poor visibility.
It is easy to understand the importance of good visibility in underground mining operations. After all, there is no light in an underground tunnel, and any illumination will have to be provided by the workers themselves. In fact, recent studies regarding underground mine safety have centered on not only total illumination levels, but the quality of that illumination and the effects it has on safety records and worker ability to identify and avoid potential hazards. These studies are being performed because of the major shift in lighting technologies now being applied to the industrial sectors, most notably LEDs. While a lot of mainstream concern regarding new lighting technologies has centered on aesthetics and efficiency parameters, the industrial and commercial lighting sectors require more in depth evaluations in performance relating specifically to the safety and efficiency of work operations under these new lighting technologies versus old HID and incandescent lighting.
The work done regarding LEDs in mining conditions has been promising, with noted improvements in contrast and color reproduction which have lead to measurable improvements in worker ability to perceive potential hazards in the form of rock faults, tripping hazards, and peripheral acuity. Currently, the traditional mining cap lights worn by underground miners has been a relatively strong area of study focus, and led to the implementation of LEDs into these portable luminaries as a result. However, the improvements LED offer in light quality can likely be applied to surface mining operations as well considering that similar hazards exist and improved visual acuity can be considered highly beneficial.
Although open mining operations benefit from normal ambient light levels due to natural sunlight, these operations are not confined to daytime hours. Many mining operations are around the clock in nature, and so large scale illumination is an integral part of their equipment requirements. Currently, for large scale mining activities, metal halide tower lighting is a dominant form of illumination due to its high intensity and good light quality. However, metal halide towers are susceptible to many performance factors including color shift as the lamps age, durability issues encountered with glass lamp construction, high heat, and energy requirements. Although effective, metal halide mining lamps require fairly high levels of maintenance in order to maintain them in peak operating condition and thus providing full benefits through improved safety and worker performance.
Since the conditions around an open mining operation are highly dynamic, with work areas constantly in a state of size and location flux, most light sources are required to be fairly mobile, and so self contained light tower systems and mobile lighting systems are commonly utilized. As a result, powering these systems requires either dedicated on site power supplies or standalone lighting systems which provide their own power through integral gasoline or diesel generators. Because of this, the efficiency as well as power and quality of the lighting systems used becomes a significant part of operational costs, and improvements in lighting efficiency highly sought after. It is in these regards that LED mine lighting holds great promise, as the greatly reduced energy requirements of LEDs alone is easily translated into reductions in fuel costs and thus operating costs.
LEDs also hold further benefits through their ability to withstand much greater degrees of abuse. Since LEDs do not utilize filaments or glass in their design and are in fact solid state in their construction, they more readily withstand the demanding and often abusive conditions encountered in mining operations. Impacts, vibrations, wetness and dust can easily lead to the premature failure of metal halide luminaries under prolonged exposure to them, and frequent maintenance is necessary to mitigate their effects. LEDs require far less maintenance due to their higher durability, which in turn also translates into reduced operating costs as well as improved safety and productivity since down time is also reduced.
For final consideration are the improvements in light quality that LEDs offer. As noted earlier, illumination grade LEDs provide very good contrasting as well as very good color rendering. In the mining environment where excavation and digging is an integral part of operations, the potential for wall collapse become significant as pits grow in size and depth. The improved contrast and color rendering of LEDs improves the ability of workers to visually detect the variations in the texture, color, and formations of pit walls that may signal a potential fault or instability that could possibly lead to wall collapses. Additionally, the improved illumination quality provided by LEDs helps to improve worker safety as it is easier for equipment operators to identify and note workers in close proximity.
Although the potential of LEDs has only recently begun to be effectively translated into the industrial work environment, current applications and studies have been showing they indeed are an effective alternative to traditional light sources. The abusive and demanding conditions of industrial mining environments as well as the high safety emphasis they require provide an ideal opportunity for the benefits of LEDs to be fully realized and thus perhaps allow a full migration away from traditional HID and incandescent light sources.
As LED technology continues to advance at a rapid pace, expect to see an increase in their application among industrial operations such as mining. The improvements in safety, efficiency, operational costs and light quality LEDs offer promise to eventually revolutionize not only how we illuminate our homes, but our workplaces as well.