photo: AngloGold Ashanti mine in Tanzania

Published with permission from Miningiq.com

At a recent worldwide technology convention a consortia of some of the most established technological names are collaborating to introduce automated, blast-free, continuous gold mining at depths of 5 km underground. This comes right of the back of an interesting week for mine automation with the recent automation announcements from Rio Tinto.

Gold-mining company AngloGold Ashanti has brought together 30 companies and 80 participants in its “open innovation” platform from which scoping, feasibility and prototype stages could emerge as early as the second half of 2011.

In the first steps towards the new mining paradigm, AngloGold Ashanti plans to:

• stop all blasting;
• create peopleless stopes;
• mine around-the-clock every day of the year; and
• refocus on revenue.

 

South Africa still has one of the biggest gold resources in the world, but it is at depth, which results in significant amounts of gold having to be locked up in shaft pillars and stability pillars, because blasting snarls up the ground conditions and creates dangerous seismicity.

“The way that we’re mining now is not sustainable into the future,” AngloGold Ashanti executive vice-president for South Africa Robbie Lazare told Mining Weekly Online in a video interview.

 

Compared with the 274 working days in South Africa, AngloGold Ashanti’s global competitors mine 365 days a year at only 5% to 10% dilution.  Also, the South African gold-mining industry mines for only ten hours out of the daily 24 hours, as a result of the long travelling time to rock face and blasting.

“We want to safely mine all the gold, only the gold, all the time,” AngloGold Ashanti senior vice-president technical Mike MacFarlane told Mining Weekly Online in a video interview. “We’re leaving 40% of the gold behind in pillars. We’re diluting the ore by more than 200%, and mining only 75% of the available shifts,” said MacFarlane, formerly of Inco in Canada.

The new technology process, which has already been under way for nearly a year, involves a spread of academic, research and business skills collaborating across various time zones.

An “open innovation” approach has been adopted with technology titans that include General Electric, 3M and DuPont, the combined research and development budgets of which are said to collectively exceed $7-billion.

Quick-win steps have been included in the proposed overall stepchange, which is seen as being essential for the mining of more than 100-million ounces of AngloGold Ashanti gold that conventional mining methods cannot safely access.

“The long term is playing out together with shorter-term quick-implementation pieces,” AngloGold Ashanti vice-president operations Mike O’Hare elucidated to Mining Weekly Online.

What is termed “horizon-three” technology will result in mine workers being removed from the high-risk deep-level areas, ultra-deep resources being profitably accessed, and a competitive advantage opened up in deep mining.

The process’ third technology workshop took place to deal with 15 concept areas that have been established by the two previous three-day workshops that took place last year, following the application of rigorous “fail-fast” principles, which quickly eliminate inappropriate solutions.

This workshop is expected to pave the way for scoping, feasibility and the requirements for prototypes where appropriate, says AngloGold Ashanti vice-president strategic project design Shaun Newberry.

 

BYPASSING MECHANISATION

While South African gold mining has, by and large, not participated in the mechanised mining era, which has been widespread since the Seventies, the new steps are being taken to enable the country to leap from the current manual era directly into the automation era and completely bypass the mechanised era, where most of the global mining industry is currently stuck.

While mechanisation has brought substantial productivity improvements in Canada, the US and Australia, Western-world mines trying to automate the mechanisation processes are finding the going limited. “The good news for us, is that we didn’t spend all that money to find ourselves locked in the mechanisation paradigm, so we have the opportunity now to bypass the mechanisation stage and go right to the automation,” MacFarlane said. Core competencies will have to be redefined and new sets of skills learnt, on a foundation of safety, a real-time single information source, reduced energy and automation.  An advantage of the platform that has been created is that large multinationals are able to link up with small mining suppliers.

AngloGold Ashanti has no problem with other mining companies choosing to join its effort.

“We’ve been at this for a year and a lot of work has been done. We’ve got buy-in from big companies with huge research and development budgets, and we’re getting things done as quickly as we can,” said Lazare.

While the five-year project is under way, a number of off-the-shelf technologies that form part of the vision, are being introduced quickly to improve safety and to increase productivity.

Earmarked for early attention are rocker shovels, which can be automated in the near term, underground logistics and communication backbones.  A South African-developed virtual workspace for round-the-clock real-time interface – “the engineers’ version of Facebook” – also has a front-end webspace for general public participation.

Technology providers are putting new slants on off-the-shelf technologies, one offering dilution-free boring of the reef in a nonexplosive environment. AngloGold Ashanti is committed to applying the new technologies in the Mponeng deepening and the Moab Zaaiplaats megamines that have 30-year to 50-year lives. The team has been surprised to see how far nonblasting technologies, which support continuous mechanical cutting of reef, have advanced. “What we are doing now is probably the most comprehensive technology intervention in the world,” said Lazare.  The last large technology project that AngloGold Ashanti conducted was Projek Katleho, which ceased in mid-2003. The big difference this time around is the move to no-blast operation.

Mike McFarlane, VP Technical for AngloGold Ashanti is the keynote presenter at this year’s Mine Site Automation and Communication Summit in South Africa where he will be presenting on advancing the frontiers of intelligent information. For more information about this event please email enquiry@iqpc.ae