Lower Grades Mandate Robust, Efficient Solutions

Suppliers increasingly offer customizable, fit-for-purpose material handling solutions that address project-specific needs

By Jesse Morton, Technical Writer

The trends in the mining industry most relevant to the material handling business are declining grades, limitations on input resources like water and energy, building pressure to reduce fossil fuel consumption, and the increasing need to minimize environmental impact, according to Fluor Corp.

“Declining ore grades, increased processing volume, along with a requirement to drastically reduce water and energy consumption drive a need to scan and screen ore, and separate the waste even before any material enters the process plant,” said Claudia Baerwolff, director, mining and metals strategy, Fluor.

“The shift from small, narrow vein underground deposits toward large, low-grade block-cave projects require a much more robust material handling infrastructure,” she said.

The push to reduce carbon emissions “increases demand for conveying solutions, not only for long-haul overland conveyors, but also for (in-pit crushing and conveying) solutions,” Baerwolff said. “Capital efficient, agile, innovative solutions are explicit demands we receive from clients, oftentimes with a preference for a vertical design and supply package.”

Miners are also demanding greater automation and digitalization, said Bracken Spencer, principle engineer, Alpine CME. “Material handling, especially in underground mines, is taking phase shift advancements toward automation, system integration and real-time product tracking, from the face to the mill,” he said.

“While the initial installation capital expenditure is higher, the downstream benefits of increased personnel safety, system efficiency, and increased productivity and throughput quickly offset the higher capital cost,” Spencer said. “These changes start by asking ‘why’ as opposed to accepting that the status quo is good enough.”

When it isn’t good enough, suppliers must “design and supply solutions that address project-specific needs, and deliver fit-for-purpose material handling solutions that include custom configuration, innovative design and at a lower cost than the competition,” Baerwolff said.

Many suppliers are increasingly successful at doing exactly that.

Unleashing Mine Design Creativity

Recent news from Rail-Veyor Technologies Global Inc. suggests the company is growing its market share for all the right reasons. The company reported that in 2020 it made headway on projects in Asia and elsewhere, won a sustainable mining solutions competition, and continued to innovate.

Rail-Veyor’s flagship solution, the TrulyAutonomous haulage system, is an electric train capable of hairpin turns on a 20% grade. The standard car is 2.4 m long and connects to others with spherical bearings. The train supports a continuous, articulated trough. Sideplates on the train are pushed by multiple drive stations along the route. Typically, at any given time, a train is propelled by multiple drive stations.

The system is custom engineered for each project. It is designed to meet tonnage requirements, and is run by software and without a dedicated operator.

It puts out no emissions, causes little dust and presents no fire risk. That means it solves some major challenges, and thus is increasingly in demand, the company said.

Currently, a TrulyAutonomous system is being installed in a mine in Kazakhstan. “It has been challenging to do this in the middle of a global pandemic, but working with local and regional suppliers and trusted local consultants has allowed the work to continue within the guidelines of the government,” Jim Fisk, executive chairman, Rail-Veyor, said. The “project is under way with 99% of the material for installation having been delivered.”

Meanwhile, the company is remotely commissioning a project in Venezuela. Elsewhere, the TrulyAutonomous system was recommended as the material haulage system of choice by preliminary economic assessments for both Troilus Gold and Rockcliff Metals.

Synchronously, Rail-Veyor won the fourth annual Mining Cleantech Challenge, hosted by the Colorado Cleantech Industries Association, in July 2020. The invitational contest awards solutions that meet current industry needs while introducing innovation to the marketplace.

And Rail-Veyor is definitely long on innovation. “We continue to innovate the most transformational material haulage system in the world,” Fisk said.

In 2020, several improvements were trialed, Fisk said. “Our latest iteration of our train car has a rubber lined trough to make the trains lighter,” he said. “The flexible nature of the material of the car trough will virtually eliminate material carryback and need for cleaning residual product.”

The company recently designed over-under bypasses in areas where room for side-by-side bypasses is limited due to clearance and geology. “We’ve conducted rigorous successful testing at our John McCall Test Facility in Sudbury, Ontario,” Fisk said.

Separately, the company designed a 1.5-m train car to navigate super-tight curves. “This allows for a smaller discharge loop to unload the material,” he said.

The TrulyAutonomous system has proven popular with customers, which report savings of as much as 90% over previous traditional truck-haulage systems. “A few of our current customers are looking into second, third, and sometimes fourth systems, either to expand their current system or in other locations,” Fisk said.

“Our opex is the most competitive in the industry,” he said. “And the capex can be offset by the savings in development and ventilation requirements in underground applications and by reductions in haul road development and maintenance in surface applications.”

For example, Agnico Eagle installed a 166-m train at Goldex in 2017. Part of the Deep 1 project, the miner adopted it to move low-grade ore from the lower part of the deposit located at more than a km underground at a cost of less than $40/metric ton (mt).

The train could handle big rocks, so no new crushing solution was required. It cranked out no fumes, so no additional ventilation was needed. Because it could hug the curves of the existing route to the working area, development costs were minimized as compared to conveyors.

Since the commissioning in January 2018, components have been upgraded, real-time detection systems installed, and a dedicated maintenance bay was designed and built, David Paquette, maintenance general supervisor, Goldex, said. “Before, maintenance on the trains was done in the main Rail-Veyor ramp, so we had to shut it down to perform the maintenance work.”

At Goldex, Rail-Veyor’s “performance has continued to improve, and has not yet reached full maturity,” Paquette said. “Since 2018 to date, production has more than doubled and is above design. As for maintenance costs, the figures have been steadily decreasing, and to date they have declined by more than half since its commissioning.”

Goldex now has six trains with a total of 408 cars, and hauls around 7,000 mt/day (mt/d). “We meet or beat what we say we will do,” Fisk said.

Which garners the praises of customers like Sean Boyd, CEO of Agnico Eagle, said Lisa Youngblood, executive director, communications, Rail-Veyor. “We have heard from our customers that Rail-Veyor, as a company, is the best vendor they have ever worked with,” he added.

The system is popular with engineers because it allows them to “unleash their creativity to explore mine design in a way never thought of before,” Fisk said. “Our ability to climb greater than 20% gradients and also go around tight curves without the need for additional ventilation or haul road maintenance will completely change the sustainability model for mines.”

Automating Stockyard Operations

FLSmidth reported seeing an uptick in demand for digital solutions for optimization, like BulkExpert.

“The trend backs our feeling that one of the big areas of growth will be digitalization,” said Franz Rietschel, product line manager, group digital, FLSmidth Mining.

BulkExpert is an automation system designed to optimize stacking and reclaiming operations. It consists of a highly accurate positioning and laser scanning application that creates a model of the site and a machine for intelligent machine control, the company reported.

Positioning hardware and machine modelling provides accurate information on machine movements. Algorithms and control philosophies add intelligence to the machines.

Benefits include improved productivity, increased equipment uptime and longevity, and reduced energy consumption. The system can be used to, among other things, flatten peak loads, speed ship loading and cut CO₂ emmisions, Rietschel said.

“The offering for yard machine automation has a wide range of solutions,” he said. “Different options are available, starting from automation to operate the machine fully automated controlled by a PLC, or more advanced with an autonomous solution.”

Recently, it was purchased by a miner to fully automate the stockyard operation of two large iron ore shipping export terminals in Brazil. The customer previously deployed BulkExpert to a port stockyard in Southeast Asia.

At the Brazilian terminals, the solution is being used to increase reclaim throughput and equipment efficiency, the company reported. Remote operation, anti-collision and collision-avoidance systems will reduce stoppages. Quality management will track material movements, and material blending control will reduce quality deviations.

Expected benefits include higher throughput and improved performance, the company reported. Extended machine life and reduced maintenance will result from lower stress on the machinery.

Separately, FLSmidth designed and supplied two large stockyard machines for a miner in Australia. The supplier reported it is currently building a bucketwheel reclaimer and a traveling stacker with a luffable and a slewable discharge boom.

The reclaimer will feature state-of-the-art stockyard machine technology meant to improve the accessibility and maintainability of the components, FLSmidth said.

“A further refined bucket design reduces carryover of material and minimizes micro-spillage because of reduced gaps between the bucket teeth,” said Branco Lalik, director, mining systems, FLSmidth Mining. “Additionally, a special optimized sealing system between bucketwheel and ring chute was developed and implemented.”

FerroCer impact wear liners for the buckets could double the bucket exchange frequency and reduce maintenance costs, he said.

“On top of that, the rotable bucketwheel head can be exchanged as one complete unit including the steel structure, bucket-wheel drive and ring chute, which increases the uptime of the whole machine in operation,” Lalik said. “The automation and control package, with radar-based stockpile scanners, provides increased efficiency, a higher level of safety, and it also helps our client to monitor his inventory.”

Rising metals prices bode well for the company’s material handling solutions business. “There is increased activity on the projects side, and we expect this to have a positive impact, even considering the pandemic situation,” Lalik said.

For example, the supplier has won two orders for H2 2021 for stockyard equipment for a mine and a port in Brazil. Supplying a drum reclaimer and a bucket wheel reclaimer extends “our large installed base of mobile balanced machines in South America,” Lalik said. “It confirms that we are well-positioned in this segment.”

South Flank’s Horizontal Curves

Like the Nazca lines or the canals of Babylon, the overland conveyors for BHP’s $3.6 billion South Flank project must be viewed from the air to be fully appreciated. The sprawling 14-km, 90° curved conveyor is a “state-of-the-art implementation of complex conveyor design” in one of the most forbidding environments on the planet, Fluor Corp. said.

Engineered by Fluor and partner AC-Tek, and executed by an integrated BHP and Fluor team, the design is of the most advanced complexity, said James Markey, project manager, Fluor.

“Horizontal curve design in high-capacity overland conveyors is unique, and this combination of length, capacity, vertical terrain and horizontal curves was not previously attempted,” he said. The design process involved, among other things, dynamic modelling of the elastic behavior of the conveyor under numerous load cases, horizontal and vertical curve analysis, terrain modeling and optimization, and component configuration and optimization.

Conveyor geometry and material selection was carefully considered to reduce power draw along the conveyor, Fluor reported. This resulted in a design using belting with low indentation losses and lightweight composite material idlers. Lighter rollers reduced installation and operating costs.

The conveyor was designed to add value in multiple ways, said Neale Watson, executive director, engineering, Fluor.

“Incorporating horizontal curves in high-capacity overland conveyors is a unique specialty in the industry, and can effectively replace two or more conveyors and associated transfer points,” he said. Benefits include increased power efficiency, reduced component wear, and lower capex and opex. “Conveying solutions have a high impact on an operation’s carbon footprint, which is why we look at material handling as a core pillar of our mining and metals business.”

Nearing completion, the South Flank project will replace production from the prolific Yandi mine.

Beyond a total of 25 km of overland conveyors, the centerpiece of the project is an 80-million-mt/year crushing and screening plant, stockyard and rail-loading facilities.

Because of the remote location, “the project is using modular construction techniques to speed up the build and reduce exposure hours on site,” Markey said. “The modules, with some weighing up to 350 mt, are the biggest ever delivered into the Pilbara.”

Ultimately, upon completion of the project, Fluor will have managed more than 2,300 individual modules, 300,000 fabrication drawings, 36,000 mt of fabricated steel, and a staggering 2.5 million individual assemblies.

“Fluor offers industry-leading capabilities in modularization and prefabrication with the highest standards of budget and schedule control, and maximized site safety,” Watson said.

Construction at South Flank began in in mid-2018. First production is expected this year.

“South Flank will form part of the largest iron ore processing facility ever built in Western Australia, and one of the largest in the world,” Markey said.

Modelling Designs to Up Production

WSP reported that, beyond working closely with the customer, disciplined design management and powerful digital tools were the keys to the massive success of designing a duplicate coal handling facility for Glencore’s open-cast Rolleston mine.

The engineering firm was contracted by Glencore to design the parallel plant, determined to be the most viable means of increasing coal production at Rolleston.

The original plant, commissioned in 2005, had a dump hopper, three-stage sizing system, and a linear traveling and luffing stacker. Upgrades to the crushing and stacking circuit over the years enabled the plant to process up to roughly 4,000 mt/hour (h) of two types of coal. The reclaim system moved about 4,500 mt/h to the train loadout.

Initially, Glencore considered debottlenecking it, but there wasn’t the space for the needed equipment, WSP said. “To overcome these constraints, the existing coal handling facility would require major changes, necessitating major production interruptions,” said Bintan Malar, marketing lead, WSP.

Instead, theoretically a duplicate plant working a parallel product stream could “increase throughput capacity, operational flexibility and production continuity,” he said. It would have a higher direct capital cost, but without a significant interruption to production.

The challenges WSP bested were many. It had to develop detailed designs, position the new facilities on an existing site, design capacity upgrades to the train-loading conveyor, and design the foundations and retaining wall for the facility, which was located on top of a 14-m-high unconsolidated pad.

“In ensuring the upgrade was future ready, we had to make allowance for the new coal handing facility to feed to, and receive product from, a future dry destoning plant,” Malar said. That meant, among other things, that a belt plough station had to be later fitted on the stacking conveyor, he said. “Likewise, calculation and spatial allowance was made to receive weighed, destoned product coal.”

The project, of course, involved multiple contractors, and had a tight timeframe and budget.

Complicating things, the designs would have to be made with limited data on the major equipment. “WSP managed this risk by detailing the design interfaces in the datasheets and by rigorous checks of the vendor drawings and 3D models, when available,” Malar said.

The engineering firm used what it described as a multidiscipline 3D model when generating drawings. “That improved the confidence of delivering a quality product in such a compressed timeframe,” he said.

“The project was complex and involved numerous detailed interfaces,” Malar said. “WSP’s designers could review these interfaces in a virtual model environment before putting pen to paper. The use of 12D, Prosteel and Inventor enabled WSP to utilize a wider range of 3D and 2D design resources.”

The collaborative 3D model incorporated data on earthworks, equipment, the process, the structures and various services. “It facilitated clash detection and elimination,” Malar said. “It enabled visualization for Glencore’s team.”

It also helped with safety and operational reviews, and with troubleshooting potential issues with construction. “It allowed us to show detailed models to be checked and compared with original design models,” he said.

The modelling ultimately was used beyond the design phase. “WSP provided the civil design 3D model as one of the deliverables for use in the construction of the project,” Malar said.

WSP completed the project on time and within budget. “The new Rolleston parallel coal handling facility is a clever solution to the business imperative of rapidly increasing throughput at an existing mine site,” Malar said. “Glencore and WSP worked as a team to overcome the challenges of a fast-tracked schedule, low capital costs and minimal interruptions to production.”

Such collaborative work “is what leads to successful outcomes,” he said. “Upgrading the Rolleston coal handling facility is a great example that demonstrates the benefits of working closely together so that clients can determine the right solutions that fit their needs, now and into the future.”

Introducing Maintenance 4.0

ABB Ability Asset Vista Condition Monitoring helps Vale’s S11D mine avoid downtime and reduce maintenance costs, ABB said. “The solution payback time was achieved in only a few months,” said Eduardo Botelho, product manager, global material handling service, ABB.

S11D is described as one of the largest open-pit mining operations on the planet, with an annual output exceeding 100 million mt. There, “Asset Vista covers the open-pit mine and processing plant, with more than 10,000 assets under monitoring,” Botelho said.

“Asset Vista helps the maintenance teams’ opex, targeting bottlenecks that could be electrical, mechanical or in automation,” he said. “It integrates monitoring with customer maintenance strategies, but also adds value to the capex investment, making use of the large amount of data available in the existing system.”

The system is an integrated portfolio of maintenance capabilities, sensors, connectivity, data aggregation, visualization and analytics to support decision making. “Customers benefit from access to big data and the ability to compile it efficiently using dashboards to sustain and improve maintenance performance,” Botelho said.

Information from different condition monitoring systems, such as vibration analysis, can be integrated into a single platform. That platform can talk to enterprise asset management and computerized maintenance management systems. It “breaks down traditional barriers to information, and can be accessed through PCs, notebooks, tablets and mobile phones,” Botelho said.

“It can be applied to virtually all critical asset types in a mining plant, removing traditional information silos and creating a single focal point,” he said. “It is ABB’s top solution in asset management applications and has modular, compatible and expandable features.”

The system can help a miner transform maintenance operations from being driven by abstract deadlines to being driven by condition-based monitoring, he said.

Bridging the Chain Knowledge Gap

U.S. Tsubaki reported the ProService chain and lifecycle support package increases the reliability and lowers the operating costs of Tsubaki solutions.

“It is composed of a unique and comprehensive portfolio of technical and field support resources that have proven to foster reliable and predictable chain and sprocket performance,” said Mike Darragh, senior product manager, conveyor chains, U.S. Tsubaki Power Transmission. “Tsubaki will build the ideal chain for an end-user’s project, optimize it as their needs change, and proactively assist in its performance throughout its entire lifecycle.”

The core services include system optimization, installation support, inspections, wear analysis, performance tracking and personnel training. Benefits include improved reliability, lower cost of ownership and predictable performance, the company reported.

“Tsubaki ProService provides end-users the proactive resources necessary to ensure they get the maximum value and performance out of their chain and sprocket systems,” Kris Ferguson, field engineering manager, conveyor chains, U.S. Tsubaki Power Transmission, said. “This is often referred to as the Tsubaki difference.”

The offering arose as data from the field showed that general knowledge of mechanical chain systems was on the decline throughout the industry. “Over the last decade, Tsubaki diligently surveyed its customer base and studied the root causes of customer-reported issues and complaints,” Darragh said. “In virtually all cases, poor installation or maintenance practices had led to the demise of the supplied product.”

Tsubaki solutions typically have a higher upfront cost but a lower overall total cost of ownership due to superior quality. “Yet in order to achieve this, the product must be properly specified, installed, and actively maintained,” Ferguson said.

“In order to safeguard the true value of Tsubaki, a technical field service team or professional service offering was needed,” he said. “It had to be a lifecycle-engagement program, an embedded partnership.”

Since launching, the program has been “very popular” and “has delivered substantial success,” Darragh said.

“Feeder breakers, bucket elevators and stacker reclaimers are the typical production-critical applications that our engineers are involved with on a day-to-day basis,” he said. “Challenging applications within synthetic gypsum, coal, gold, copper, molybdenum, pet coke and fly ash are the very installations that Tsubaki ProService was built for.”

With the customizable program, service cycles are rendered reliable, predictable and trackable. Such pays dividends, Ferguson said.

“In many cases, service lives have gone from a year or less to greater than five years,” he said. “Not only does lifecycle duration increase, but overall throughput and productivity also typically elevate.”

Also, with the program, U.S. Tsubaki evolved, Darragh said. It proved to be “the catalyst that has taken Tsubaki from a traditional reactive product supplier to a proactive and comprehensive lifecycle solution provider,” he said. “Tsubaki’s commitment to a customer goes far beyond the product itself.”

Effectively Removing Carryback

Martin Engineering reported the CleanScrape Secondary Cleaner (CS2) was designed for longer life, low maintenance and safer servicing. “The system represents a revolutionary concept that delivers superior cleaning and up to four times the service life of conventional designs, with half the maintenance,” said Dave Mueller, conveyor product manager, Martin Engineering. “The combination has been shown to remove as much as 99% of the carryback in most belt-cleaning applications.”

CS2 can be used with any primary cleaner, but was engineered to be used with the company’s original CleanScrape Primary Cleaner. “When used together, they form a rugged, low-maintenance system that effectively removes carryback, helping to prevent fugitive material and the associated cleanup,” Mueller said.

The solution is ideal for challenging applications, including those defined by space limitations. It “is particularly effective in conditions where continuous production is a high priority or cleaner service is difficult,” Mueller said.

It typically requires only one re-tensioning, ever, and “the extremely low maintenance requirements and outstanding cleaning ability help reduce the cost of ownership,” he said.

CS2 is made of stainless steel. The carbide blade tips have a small corner radius to protect against belt damage. Each is on spring-loaded arms. “The load springs allow independent blade rotation back and forth, as well as up and down,” Mueller said.

“This range of motion provides equal load pressure across each blade, bypassing obstructions and conforming to ever-changing belt undulations,” he said. “The unique design holds the blade in an effective cleaning position but allows the blades to retreat for reversing belts or rollback.”

The negative rake angle reduces wear on the belt cover. “With the negative rake angle, CS2 delivers outstanding performance, while mitigating the potential for belt damage,” Mueller said.

The solution is designed to shed removed material, which falls back into the cargo flow. “This ‘free flow’ design, with an absolute minimum of exposed surface area, delivers optimum cleaning results while allowing material to pass through the arms,” he said.

It requires minimal space, and can be installed inside or outside discharge chutes.

The solution is also available in a Safe-to-Service configuration. It can be serviced by simply sliding it out on a track. “Because the cartridge extends outside the conveyor path, maintenance or blade replacement can be performed without confined space entry, helping to minimize the hazards to staff,” Mueller said.

CS2 furthers the company’s mission to make bulk material handling cleaner, safer and more productive, he said.

“The company operates under the assumption that safety should be designed-in whenever a new or improved product is being considered,” Mueller said. “Every component that the company supplies is engineered with this in mind.”

Improving Particle Size Distribution

Hexagon’s mining division reported a customer in Peru using HxGN Split-Conveyor Cam and other HxGN Split solutions improved particle size distribution (PSD), mill energy consumption and mill throughput.

“The open-pit mines saw a $7.5 million per month revenue increase thanks to the use of HxGN Split fragmentation analysis technology,” said Brian Norton, director, business operations, HxGN Split, Hexagon Mining.

Split-ConveyorCam is a “monitoring system employing image processing technology for particle size, shape and color for any conveyor belt or feeder location,” Hexagon reported. It gives “an automatic online measurement of the PSD,” Norton said. Such “immediate feedback” can be used to manage and improve crushing, screening and milling.

PSD can be used to “ensure the operation is crushing and sizing to the desired specifications,” Norton said.

“Split-ConveyorCam provides information for control of crusher settings and information on the integrity of screen decks,” he said. “An operator can manually adjust crusher settings based on crusher product readings, and can know when a screen deck is malfunctioning and passing out of spec rocks.”

PSD can help in identifying needed crusher maintenance, and can be used in technical calculations for improving the energy consumption of a comminution circuit, Norton said.

The image-processing and rock-sizing algorithms used by the technology were first developed by the University of Arizona in the mid-1990s. “Split Engineering was founded in 1997 with the objective to commercialize the software and systems for the worldwide mining industry,” Norton said. “Hexagon acquired Split Engineering in 2019.”

Hexagon adds value by installing HxGN Split solutions such that the customer can fully utilize and benefit from them. “We provide experienced engineers who come to your site to promptly design and commission a system, and will train your personnel how to use and maintain the system,” he said.

Hexagon can also integrate a HxGN Split system into broader mine-management solutions, “which is in line with the greater Hexagon vision for an autonomous future,” Norton said.

“PSD information from blasting is a great metric,” he said. “But even greater value for the customer is easily, automatically connecting this information to the mine plan and design for further evaluation with the goal of continuous process improvement.”

Currently, there are more than 550 systems installed for roughly 140 mining customers around the world.

Capturing Data on Idlers

Continental reported its autonomous conveyor idler and roller inspection service for open conveyors can help a miner improve maintenance planning and reduce downtime. The service uses aerial drones and sensors to inspect and detect failures, with results available online.

The drones are equipped with infrared and RGB cameras. The data are uploaded and then analyzed by software, with the results presented on a web app.

Drone flights can be done automatically or manually, the supplier said. “The data are uploaded while the drone batteries are being charged in the drone base station,” said Clemens Panzer, project lead, conveying solutions, Continental.

“The data analysis algorithm automatically generates the results and identifies failing idlers,” he said. “After charging and data upload are completed, the drone is ready for the next take-off.”

The service allows miners to make better maintenance plans that target greater uptime.

Roughly 10% of unplanned shutdowns of conveyors stem from idler issues, the company reported. That has driven many miners to launch maintenance teams dedicated to idlers and rollers. Those teams often lack the technology to make data-driven decisions, Panzer said.

Historically, “maintenance planning has been based on inconsistent data, and puts the miner in a reactive position,” he said. That means damage is often discovered too late. “Maintenance and repair work as well as cost-intensive downtimes are unavoidable.”

Contrarily, Continental’s conveyor inspection service allows the miner to be proactive. It enables a maintenance department to shift personnel away from inspection tasks and to the maintenance process. “Inspection quality will be increased thanks to higher inspection frequencies and more reliable data,” Panzer said.

Typically one drone is able to inspect all of the conveyors at an operation.