The use of Smart Markers in cave mining is gaining momentum. A growing number of companies are employing Smart Markers optimise mining and to ensure that their caving projects yield the promised returns on investment.

This year’s Massmin Conference (Sydney, May 2016) had a significant number of papers that directly are based on Smart Marker data or which mentioned the use of Smart Markers in their mines.

We want to congratulate the authors of these paper and the people involved at mine sites for their excellent work and their contribution to the mining industry. We’re very proud that the Smart Marker has helped contribute to this valuable body of industry research.

• “Modelling of Real-time Marker Data to Improve Operational Recovery in Sublevel Caving Mines” by G. R. Power and A.D Campbell
• “Full Scale Flow Marker Experiments at the Ridgeway Deeps and Cadia East Cave Operations” by I. Brunton, J. L. Lett and T. Thornhill
• “FlowSim – A Versatile Flow Simulation Tool to Quantify Extraction and Design Alternatives for Blcok Caving” by R. Castro, A. Hekmat, M. Fuentes, F. Armijo and F. Rodriguez
• “Undercutting to Surface Breakthrough – Cadia East Panel Cave (Stage 1)” by J. L. Lett, I. Brunton, G. W. Capes, A, Jaeger, B. Mobilio, J. Rachocki, G. B. Sharrock and M Secheny
• “Fragmentation Prediction and Assessment at the Ridgeway Deeps and Cadia East Cave Operations” by I. Brunton, J. L. Lett and T. Thornhill
• “Geotechnical Challenges in Cave Monitoring – a Modern Approach” by J. L. Lett, A. Jaeger, J Rachocki and B. Mobilio
• “Draw Control Optimisation along the Production Drift in Sublevel Caving Mines” by G. Shekhar, A Gustafson, P. Boerg-Jensen and H. Schunnesson
• “Wireless System for Monitoring Cave-back Propagation” by S. Steffen, J Poulsen, A Van As, S. Talu, G. Watt and J. S. Ooi
• “Understanding Rock Mass Behaviour through the Development of an Integrated Sensing Platform” by E. Widzyk-Capehart, C. Hoelck Teuber, O. Fredes, V. Rivero, E. Sanchez, I Pedemonte, N. Gonzalez and S. Steffen
• “Gravity Flow Full-scale Tests at Esmeralda Mine’s Block-2, El Teniente” by D. Garcezs, E. Viera, R. Castro and M. Melendez
• “Holistic Approach to Study Gravity Flow at the Kiruna Sublevel Caving Mine” A. Nordqvist and M. Wimmer
• “Cave Tracker Flow Monitoring System Installation at Argyle Diamond Mine” by D. Whiteman, S. Talu, G. Watt, A. Van As and P. Kuiper
• “Geohazmap Implementation in Block Cave Mines” by S. Talue, E. Savage and S. Howe“

For more information about accessing the papers, please visit: http://www.massmin2016.com/

Elexon Mining is exhibiting at Massmin 2016. This once-every-four-years exhibition is the premier mass mining event. Our team will present a number of papers on the technologies we have developed, and our booth is set up to help attendees learn more about the benefits of our products.

It’s fantastic to see the growth in awareness of Smart Marker and Cave Tracker, and to also hear our collaboration partners include our products in their research papers.

The upcoming Cave Tracker paper to be delivered by Dylan Whiteman on Wednesday 11th May is generating a lot of excitement, especially as he has some ‘hot off the press’ data to share with the audience.

Read more about Massmin: http://www.massmin2016.com/

Reconciliation of the recovered resource is an important instrument for assessing the performance of sublevel caving mines. While the quality of reconciliation has improved significantly the method requires a significant period of production history in excess of 18 months before valid local conditions can be incorporated in recovery estimates. The introduction of computer models which allow processing of large datasets has greatly aided the process however the inability to measure post mining voids allows the effect of essential assumptions, made for recovery estimation, to have potentially significant impact.

Without other physical measure systems there is no possibility to either access production method improvements believed to benefit the operation or confirm that the recovery estimation process employed models the physical actuality sufficiently and with good confidence in the modelled result.
The introduction of Smart Markers has been a game changer to enabled mines to efficiently monitor ore recovery with minimal production impact and fast results.

The Reconciliation process and ore recovery monitoring are complementary methods focussed on optimising the sublevel caving system to the local geological and geotechnical conditions. Reconciliation indicates overall performance of the mining system. The understanding of ore recovery mechanisms identifies areas for improvement of ore recovery and reveals causes for under-performance in grade and tonnage. It also provides a guide to the maximum and minimum recovery estimation that any model should be bound by.

Together they enable mining to be engineered and optimised to maximise projects’ performance and economics. For example: Reconciliation may indicate that primary ore recovery is lower than predicted leading to potentially lower recovered grade and higher unit costs. It will not reveal the reason for the poor system performance. Drill and blast practices, suboptimal in the local conditions, are one likely cause for this shortcoming. Drill and blast may fail to mobilise ore in the targeted burdens and therefore achieve lower than estimated primary recovery. Drill and blast improvements, targeted with recovery monitoring systems, can increase primary recovery and therefore delay grade dilution. Potentially, this may reduce the need for low grade overdraw late in the mine life in attempts to recovery remnant resources believed to be remaining in the cave.

Small improvements in primary recovery over several recovery levels will have significant effects on project economics, reducing unit costs, improving margins and raising NPV.

China’s exponential growth has been driving the growth in the resource industry, but the country’s consumption of minerals is slowing. The resource industry is moving from a price driven expansion strategy to a cost driven business approach.

Controlling costs and risks is gaining importance during this cycle of the resource industry. This in effect is resulting in mining companies looking into innovative ways in which it can improve its extraction efficiency – especially in the underground mining sector. There is usually a higher cost involved in underground mining, when compared to surface mining. In order to replace low-cost surface operations, large-scale underground mass-mining methods are gaining importance. Underground mining, however, comes with its own set of technical challenges and uncertainties, as it is not easy to see what you are doing.

“We know that the ore body is there, but the question is, how are we going to extract it in a cost efficient manner and are we extracting the targeted ore body? Leaving ore behind and extracting low-grade material which originates from outside the targeted ore body, can have a massive impact on short-term profits and the mine’s net present value,” Elexon Product Manager Simon Steffen says. “Excessive ingress of low grade material is an important reason for underground mines being shutdown as operations have become uneconomical,” he adds.

The team at Elexon have identified the potential of maximising revenues and the issue of uncertainty, which exists in the sector. They have since been working on solutions to improve extraction predictability and efficiency. Underground extraction in low-cost caving operations is a field where decisions are based mainly on experience and intuition, as the rock mechanics are still not fully understood.

“The data that our solutions provide these mines enables the operators to make decisions based on facts and measurements, while improving and streamlining its processes,” Steffen says. “We are focusing on developing solutions for improving extraction efficiencies and economies which are based on rugged electronic systems that can survive the underground mining environment.”

The team at Elexon’s mission is to provide solutions, which will give the mines the right information at the right time necessary to exercise a large degree of control over the extraction process. The technology solutions Elexon has developed and are currently developing include, the Smart Marker, the Network Smart Marker, 3-D Smart Marker and the Cave Tracker. Over the next 6-months, Elexon is due to release its Networked Smart Marker System. Meanwhile, the Cave Tracker and 3-D Smart Marker System which is undergoing development, is set for release in about two-years. This growing suite of solutions will be highly complementary and will provide measured feedback about the critical areas of cave mining.

The Smart Marker System measures blast efficiency and reveals ore flow post-extraction, while the Networked Smart Marker System focuses on measuring real-time cave development and propagation. The 3-D Smart Marker System will allow for real-time, micro flow tracking, Steffen says, while the Cave Tracker will be able to provide the mine operator with real-time data about macro ore flow in an underground mine.

“These technology solutions are essential to the future of mining to ensure that operations remain feasible,” concludes Steffen.

Ernest Henry Mining in north-west Queensland has transitioned from an open pit to an underground sub-level caving operation late last year, with Xstrata utilising Elexon’s Smart Marker technology to maximise ore recovery, while reducing dilution.

The Smart Marker system is a blast resistant, long-life radio frequency identification (RFID) device, which has the ability to measure ore flow electronically, in particular in sub-level and block caving operations.

Xstrata Senior Strategic Planning Engineer Alex Campbell’s role involves overseeing the caving and geotechnical aspects of the cave start-up and the transition to underground mining at the copper, gold and magnetite mining operation. “We recently started using the technology as of last week [end of November], and have installed the Smart Markers within the crown pillar between the underground and open pit operation,” he says.

The blasted ore material within the crown pillar forms an ore blanket above the sub-level cave. The purpose for installing Smart Marker system in this region is to track the flow of ore and to identify areas of potential dilution. The data from the Smart Makers can then be used to adjust the mine’s draw strategy to maximise ore recovery, while minimising dilution and ultimately improving the company’s financial return.

A second Smart Marker system will be used at the mine in 2013, to assist in characterising the flow properties of the sub-level cave blast rings, Campbell says. “The main things we are trying to focus on include, characterising width and depth of draw, as well as primary, secondary and tertiary flow behaviours over multiple levels.” The system will also assist to determine drill and blast performance including the back break and apex recovery, which has an impact on overall cave flow.

Xstrata has invested $A589 million to extend the life of its Ernest Henry operations by at least 12-years. The Smart Marker system allows the team at Xstrata to better understand what is happening inside the sub-level cave. Campbell says, like all caving operations the goal is to maximise ore grade and recovery, while minimising dilution within the geotechnical constraints of the operation.

At the moment, Xstrata are trucking ore from the underground mine via a decline at a rate of about three million tonnes per annum. This is expected to ramp-up to 6Mtpa once the hoisting shaft is commissioned in late 2013. The technology is currently being used at mine sites around the world. In Australia the technology is being used at Newcrest Mining’s Cadia East operations, as well as at Rio Tinto’s Northparkes operation in New South Wales, to name a few.

Meanwhile, Campbell says Elexon’s reputation in Australia, is one of the reasons Xstrata engaged the mass mining technology specialist. “The company’s technology is easy to use and track, plus the process involved with collecting the data is quite simple,” he says.

Elexon is also involved in the Mass Mining Technology research group, which is headed up by mining engineer and Professor at the University of Queensland Gideon Chitombo. “Having individuals with their expertise based in Australia is very helpful when it comes to customer service, and getting people out on site to assist with the installation and use of the technology,” Campbell concludes.

Elexon is a pioneer in electronically measuring ore recovery to assist underground mines in improving their extraction performance. Elexon’s mining solutions are used globally with clients across Australia and around the globe – including mines in Canada, Indonesia, Chile, Sweden and the USA. Dylan Whiteman, the Project Manager for Elexon Mining’s Smart Marker System and Cave Tracker System, talks about his role and the innovative technology used by these products.

What does your role at Elexon entail?
As the project manager I am responsible for delivering Elexon’s new projects to our clients on time and within budget.

It is very challenging to develop innovative electronic solutions for underground mines, as it involves equal measures of research and development. This requires the team to work very closely with mining companies and their mine sites, to trial the new technologies and products, which we are developing.

My work ranges from system requirements specification and architecture design to project financing, as well as planning and recruitment. The role extends to the first sales of new systems where the benefits, performance and installation details are discussed with new clients.

What do you enjoy most about your job?
It would have to be the challenging nature of underground monitoring. What we are doing has never been done before in the mining industry – so it is very exciting.

We are helping to provide answers to fundamental questions about underground rock-flow and ore-recovery. No one has been able to answer these questions before.

How does the technology Elexon creates differ from similar products available on the market? What makes it unique?
The products we develop, are unique. There are no other products for the mass mining industry, which are capable of being buried deep underground and tracked in real time over many years to measure ore flow and recovery.

There really is no other company that can do what we do.

How can the solutions Elexon is creating assist resource companies improve the way in which they operate?
Our solutions offer improvements to the mining industry in the areas of safety, ore recovery, process control and efficiency.

Miners are of course already very safety conscious, but the ability to monitor underground ore movement during production helps to further improve the level of safety. One example is by being able to monitor cave propagation on a day-by-day basis.

Improvements to ore recovery are being brought about by the ability to observe how the ore is actually flowing during extraction.

If ore is not moving as predicted it becomes possible to change draw or blast strategies. We can then observe how these changes have affected the ore flow. This offers mine managers and operators a level of process control that has never been available before.

Essentially our products offer a set of eyes into the mine.

Which resource companies are currently using Elexon’s technology?
Companies currently using our technology include, Newcrest, Rio Tinto, BHP Billiton, LKAB and Xstrata at various locations around the world. We are also in discussions with other resource companies that are interested in our products.

What do you enjoy doing if not working on Elexon’s unique technology solutions for the mining industry?
I enjoy music and spending time with my young family. I also enjoy hiking – but our young ones are a little too small for this yet!

The highlight for mass mining specialists around the world is Massmin. This year’s event, which was held from June 10-14 in Canada, was no different, with a strong presence of caving specialists.

We heard from a range of speakers, including Alan Moss (Rio Tinto), who spoke about, “Back to the basics – The need to measure”. We were delighted that the presentation was in line with the core message of our own presentation held during the conference.

A growing number of presentations at the conference also contained references to the Smart Marker System, which is excellent news, as it reinforces the work we do.

Our discussions with specialists from research institutions, mining and consulting companies during Massmin have confirmed our approach – that we need to close the feedback loop in underground mining in order to improve mining performance by reducing dilution and ore loss.

Our goal is to achieve real improvements in ore grade.  A systematic way of achieving this goal is for mines to adopt a system of measuring their ore flow, analyzing the data, trying changes to the mining method and then measuring the result. Our meetings at Massmin have made us even more confident that real improvements will be found by repeating this process. A number of mines are now planning to use Smart Markers to implement this approach.

We are delighted to have met generations of intelligent, curious and experienced caving professionals, and look forward to working together with them and contributing our share to make caving a successful low-cost and low–risk mining method. The future of caving is bright.

The mining industry is in the dark when it comes to an in-depth understanding about the mechanisms of underground mining methods based on caving, however, there is a smart solution that is addressing the issue.

It is called the Smart Marker system, developed by Elexon Mining; a company with a strong focus on creating innovative value-adding solutions to assist mining companies to improve ore recovery performance in underground mines, with a particular focus on block and sub-level caves.

One of the big issues with caving is that you don’t see what you are mining; you only see the ore when it reaches the draw points where it is collected. The consequences of unplanned material recovery are ore loss and dilution, which both of have a significant impact on productivity, safety and profit.

“The Smart Marker has the ability to measure ore flow from underground mines electronically, in particular sub-level and block caving operations,” Elexon product manager Simon Steffen said. The Smart Marker system is a blast resistant, long-life Radio Frequency Identification (RFID) device that is installed in the ore body of sub level or block cave mines. “It transfers its unique identifiers (ID’s) to the Smart Marker System Readers when extracted with the ore by a Load Haul Dump (LHD) machine.”

The reader automatically detects, logs and time-stamps the Smart Marker detections as the Markers are extracted with the ore at the production level. The overall system collates both the installation and the extraction data. “The movement of the rock is analysed based on the Markers’ original positions and where and when they are extracted,” Mr Steffen said.

Major miner Rio Tinto played a vital role in the development of the Smart Marker system with Elexon. “We recognised the importance of this technology for our operations, so we were very keen to be involved,” Rio Tinto geotechnical engineer Andre van As said.

Meanwhile, before the Smart Marker, Rio used a “Dumb Marker” system, which was basically a piece of steel with an identification tag. “Unfortunately the recovery success was low,” Mr Van As explained.

Mr Steffen said it was important to understand what was going on in the cave, as the mining company faced potential risks economically if the project went off track. The Smart Marker system allows companies like Rio Tinto to not only improve its current mining operations, but future ones as well. “We have improved our predicted models based on the data we get from the Smart Marker system,” Mr Van As said.

The team at Elexon believes the Smart Marker system has the ability to bump up the output from an underground mining operation based on the insight it is able to provide. Aside from Rio’s Northparkes mine, the Smart Marker system is currently being used at mining operations in Australia, North America, Sweden, Chile and Indonesia.