PEGGY FISHER: Technologies disrupt mining industry

Have you ever been to a working mine? If you are an OTR tire dealer, I'm sure you have, but most of you commercial truck tire dealers probably have not.

Several years ago I visited a very large copper mine for a few days outside of Phoenix and an iron ore/taconite mine north of Duluth, Minn., while I was doing some consulting work for a tire company.

Just a couple of years ago I visited a lead-zinc refinery in Mexico. Mines and their processing plants are fascinating places.

While I like trucks, mine haul trucks are something else. The BELAZ 75710, produced by the Belarusian company BELAZ, has a payload capacity of 496 tons (992,000 lbs.) and is the biggest mining dump truck in the world.

The truck is more than 67 feet long, almost 27 feet high and over 32 feet wide. The empty weight of the vehicle is 360 tons (720,000 lbs.).

It has a conventional two-axle setup but the wheels are dueled, four to an axle. For this reason it needs eight 59/80R63 tires that can each carry 102 tons (204,000 lbs.).

This truck also has four-wheel drive and four-wheel hydraulic steering, which is unusual, and it can travel at speeds up to 64 mph. Its cost is just a little more than a mere $6 million.

The Caterpillar 797F made here in the U.S. is the second largest mining truck in the world. It weighs 293 tons (586,000 lbs.), can carry a little less than the BELAZ at 400 tons (800,000 lbs.) and measures slightly smaller, a little more than 49-foot long, 21-foot high and 31-foot wide.

It is also equipped with six 59/80R63 tires. However, the maximum speed of this truck is a little faster than the BELAZ at 68 mph. It costs $5 million, and options are extra.

But if you love trucks, you gotta love these babies.

The mining industry is a global industry. Many large mining companies operate mines all around the world.

In the U.S., the mining industry plays a role in all 50 states with an estimated 1,400 mines in operations extracting coal, iron, copper, zinc, potash, limestone and other crushed rocks.

The U.S. is the world's leading producer of beryllium, soda ash and sulphur, the second leading producer of coal and the third largest producer of gold and copper.

These metals and other minerals it extracts are essential raw materials for the building and chemical industries and are also a critical part of the production of everyday electronics and consumer products.

I'll bet you didn't know that more than 65 different minerals are required to produce a modern computer.

Minerals are mined underground or through surface methods such as open-pit mining. Both mining methods use a three-stage process.

The first stage is extraction, which includes blasting and drilling to loosen and remove material from the mine.

The second stage is materials handling, which involves transporting the ore and waste from the mine to the mill or disposal area.

The third stage, beneficiation and processing, occurs at the processing plant. This stage recovers the valuable portion of the mined material and produces the final marketable product.

Beneficiation operations primarily consist of crushing, grinding and separations, while processing operations involve smelting and/or refining. Each of these stages operates in a hazardous environment employing huge equipment and perhaps explosives and also require large amounts of energy, primarily electricity and diesel fuel.

The reason mining is so energy-intensive is because of the recovery ratio of various materials being mined. For example, coal has an average recovery ratio of 82 percent, so 1.2 tons of material is needed to actually get 1 ton of coal.

Industrial minerals have an average ratio of 90 percent, while metals have an average recovery ratio of 4.5 percent. So to recover 1 ton of gold, 22 tons of material have to be mined.

I know this is probably more than you want to know about mining, but understanding these facts and processes is essential to understanding how technology is being used to change this industry.

The mining industry was hit hard by the Great Recession. Since then, it has been forced into using more cost-saving and efficiency measures.

The up side of these struggles is the breeding of innovation and the development of several technologies that are disrupting the mining industry today.

The first of these technologies is autonomous vehicles. This topic is hot in every sector of industry at the moment, and mining can be one of the greatest beneficiaries of it.

Autonomous trucks and drills already have been operating in mines around the world for the last five years and have safely moved more than 661 tons (1,322,000 lbs.) of ore.

Mines using these vehicles have reported a 20-percent increase in overall productivity and zero lost time injuries since the first trucks started operating.

As a result, they are adding more autonomous trucks to their current operations and introducing autonomy to additional mine sites. This is part of mining companies' strategies to improve safety, build capacity and remain globally competitive.

Since these huge haul trucks cost millions, Caterpillar initiated a project to adapt hardware and software for retrofitting older haul trucks with autonomous mining-truck technology so mines would not have to scrap these expensive vehicles to get autonomous functionality.

Caterpillar not only is retrofitting its own vehicles with this technology, but also Komatsu 930E mining trucks as well since many mining companies operate mixed fleets of trucks, and this enables Caterpillar to offer a total solution to these customers.

Caterpillar also offers its Cat Command for dozing, drilling and underground mining. This semi-autonomous system enables one operator to control up to three machines at one time from a remote location.

Trucks equipped with Command respond to calls to the shovel, move into position, haul to dump points and report for maintenance without an operator on board.

They interact safely with other manned and light vehicles due to Command's multiple, redundant sensing systems and maintain optimal operating speeds and safe following distances at all times.

Operators experience less physical fatigue as a result of working in a comfortable office environment and work more efficiently, and fewer people are exposed to on-site hazards. One mine reported a 50-percent reduction in the frequency of safety incidents, and the severity of the few incidents they did have was reduced as well.

Productivity also is improved since mines are able to optimize production with tight truck exchanges and eliminating shift changes. There's also less damage to machines and less downtime due to misuse and overloading.

Accurate drilling and blasting helps make every other aspect of a mining operation smoother, safer and more productive. Minor deviations from the blasting pattern can result in unevenly blasted material that is harder and more costly to handle and can also put people in danger.

Embracing autonomy

Autonomous drills that operate with more precision and more accurate depth tracking can work far more accurately, which means the material is optimally blasted, requires less time to remove the unwanted material and higher productivity. Further, operators are kept in a remote station safely away from blasting areas and the dust, vibration and other hazardous conditions that surround a working drill.

Autonomous equipment provides consistency that comes from near continuous operation and the elimination of human error. Mines now are able to operate with fewer people in potentially hazardous areas with incredible increases in productivity.

As you can imagine, safety is a top concern in underground mines that are drilling into hard rock, as is productivity. Because the hard rock is difficult to break mechanically, using the traditional drill and blast method is a slow start-and-stop process.

The mine has to be evacuated before a blast, as the explosion creates various gases. However, Atlas Copco has introduced its new line of Underground Mobile Miners that are automated and remotely controlled.

These machines eliminate the more dangerous drill-and-blast method and the need to evacuate mines during blasting hard rock. They provide a continuous hard-rock mining system that enables faster advance/excavation rates, easier scheduling and a safer work environment than traditional methods.

In addition, Mobile Miner does less damage to the surrounding rock and reduces the risk of roof falls, which improves both safety and the long-time performance of a mine.

Because mining is a big consumer of energy, it isn't the most environmentally friendly industry. Therefore electric vehicles are becoming more and more popular and are replacing diesel powered equipment to reduce emissions and address climate change.

One Slovenian company, ETF Mining Equipment d.o.o., produces all-electric, battery-powered haul trucks that change how repairs, maintenance and environmental conditions are met since they are based on an innovative Modular Technical Platform.

This company's trucks are fully powered by a heavy-duty rechargeable lithium-Ion D5 battery. Additional driverless haul unit platforms can be hooked up in a train configuration via a heavy-duty steel connection that connects the vehicles physically as well as via a data cable so that the trailing haul units' throttles, brakes and steering are controlled by the single driver at the front of the train.

The battery system creates no emissions, has very low noise levels and requires far less maintenance than a conventional diesel-powered truck.

The really cool thing about these modular-designed vehicles is that they feature components that can be removed from the vehicle for maintenance and repairs without bringing the entire truck to the shop.

Wheels, batteries and the cabin can be switched out in 15 minutes, and entire axle groups can be changed in about 25 minutes. This means that the ETF haul trucks can stay in operations while the component repairs are completed in the work shop without the truck itself. This dramatically increases the vehicle's uptime.

In addition, the major modular parts are the same for every size truck the company makes, so axles and wheels used on large trucks are the same components as smaller vehicles — there are just more of them.

All the trucks are the same width (24.93 ft.) and the same height (20.66 ft.), so replacement components fit the smaller 180-ton truck all the way up to the 774-ton truck. This enables mines to keep fewer parts on hand.

Not only is hardware changing the industry, but mining software is making the process smarter all the time too.

One innovative example of this is called X-ray Diffraction (XRD). This machine and its software quickly identify particulate materials, clays and other minerals.

The software provides detailed information about the crystalline structure of the material being mined and the amount of useful material the sample contains. High speed detectors enable data to be collected rapidly on a large number of samples. XRD analysis is performed on a pulverized sample and it is an easy and quick way to obtain mineralogical data for chemical analysis.

Mining processing technology also is being vastly improved and sped up with sensor-based sorting. Sensor- based sorting is designed to split commercially valuable minerals from ores as efficiently and cheaply as possible, which increases productivity.

Dual Energy X-ray transmission (XRT) can penetrate bricks down to 100 mm (4 inch) particle size, which enable it to detect metals even if they are not on the surface. Depending upon the configuration of the machine, a user can choose the desired minimum content of ore he wants and adjust it for that amount. This enables mines to react quickly to market conditions or changes in the input material.

Another sorting technology is X-ray fluorescence (XRF) which can be used to determine and sort individual chemical elements very precisely. Optical sorting and lasers are well suited to detect different colored ores such as copper oxide or crystalline structures in quartz.

Limestone chunks as large as 8 inches (200 mm) can be analyzed and sorted by white level. Only the purest white material passes this sorting process, while pieces with even the slightest deviation from the set values are rejected by precisely actuated compressed air valves.

Magnetic separators with double magnetic pole drums utilize a very thin belt to move the industrial minerals, such as limestone or kaolin, across them and subject the material to the highest possible magnetic field that enables it to be further upgraded.

Salts can also be upgraded or cleaned using this method, which separates out clay containing contaminants. Suspension magnets also are used to separate tramp iron (metal objects such as drill bits, anvils, hardware, etc.) on high-speed belts from coal and gold ores.

Tire solutions

When it comes to tires, mines are terminally brutal places in which to operate while carrying incredible amounts of weight. One of the biggest limitations of current haul trucks are their tires.

Besides their high cost (one 59/80R63 OTR tire costs on average $42,500), the downtime due to flat tires considerably decreases productivity of current trucks, which, as you already know, cost in the millions of dollars. Changing a tire almost 14 feet tall and weighing 5 tons (10,000 lbs.) often requires more than eight hours of work. There are several companies that are addressing this problem.

ETF Equipment provides its Central Tyre Inflation System that actively monitors and adjusts the height of each wheel to counteract bumps in the road. If a tire suddenly deflates, the system automatically alerts the driver and raises the wheel to allow the driver to continue.

Bridgestone Corp. offers the Pressure Stat tire-pressure-monitoring system (TPMS) for OTR tires. This system provides instant access to tire pressure and temperature data.

It features external valve-stem sensors, onboard alerts for drivers, Bluetooth connectivity that provides real-time pressure updates to mobile devices, instant inspection reports on desktop and mobile devices for the entire fleet and forecasting and analysis when combined with Bridgestone's TreadStat tire and management software.

Miners also can ensure the weight of their vehicles is evenly distributed with this system, which prevents uneven tire wear.

Goodyear's Proactive Solutions TPMS Heavy Duty features advanced telematics and patented predictive analytics technology. It is able to monitor tire pressure and temperature to notify operators of potential issues before they become serious.

TPMS sensors are mounted inside the tires and transmit pressure and temperature data via onboard telematics to a Goodyear server. The data are analyzed there, and alerts are sent to the mine fleet manager via e-mail or by an app using a graphic showing which tire is affected and how serious the problem is.

This data also are used to predict tire life and plan maintenance. The on-board router also has a built-in GPS function that can pinpoint the exact location of the machine on a site.

Group Michelin was the first company to introduce TPMS to the mining industry with its Michelin Earthmover Management System (MEMS) technology about 10 years ago. MEMS uses sensors inside each tire along with an onboard receiver.

Originally the vehicle communicated directly to the mine operations control center transmitting pressure and temperature data every 10 minutes. Today MEMS Evolution 4 offers a choice of two sensor models: conventional sensors and sensors for water-ballasted tires with additives that are isolated in a capsule filled with an inert liquid.

With the advancement of communication technology, Evolution 4 uses a new transceiver and antenna, which includes a GPS that enables it to provide mapping and vehicle tracking, geofencing and accelerometers continuously to the mine control center.

It has a user-friendly software platform, a hand-held reader that can take pressure and temperature measurements directly from the tire sensors and an app that can access tire and vehicle data on standard mobile devices.

SST Wireless partnered with Kal Tire Mining Group to produce an OTR system known as True Tire Technology (TTT). This system's sensors are installed inside the tire and have a unique shape that improve durability and resistance to tire additives such as Tire Life.

The shape of the sensor also increases signal strength. These sensors continuously monitor tire pressure and temperature and relay it via radio signal to the vehicle's electronic control unit (ECU). When an alert is generated, a warning light on the instrument panel alerts the driver about the problem as well as the control center.

All of these systems enable mine operators to increase safety, life of their tires, and productivity as well as reduce costs.

As you can see, technology is revolutionizing every stage of the mining process in addition to tire operation and maintenance. All of these innovations will improve safety, reduce costs, build capacity and enable mining companies to remain viable and globally competitive.

Peggy can be reached via e-mail at [email protected].