Monday, 4 October 2010

Up-take of New Technology in Mineral Processing (by Mike B)

As a company who has had the following statement on our website home page;
“The company is established as a world leader in the development and implementation of innovative cost effective technologies and processes in the field of mineral, chemical and waste processing. It has had many patents granted and has won a number of national innovation awards for its technology. The technology can achieve significant environmental benefits in terms of reduced energy and waste for operations.“
We are therefore very interested on how our industry reacts to new technology. And how our industry reacts I would say is very, very slowly. As a discussion example I’ve used technology that I currently don’t have any direct involvement with but at one time was one of the instigators in trying to get it introduced into mineral processing.
I first knowingly had exposure to high pressure grinding rolls (HPGR’s) as a metallurgist with Billiton when I was investigating their possible use for Boddington and Mt Todd gold mines in Australia. That was already in 1990. Only 20 years later, now in 2010, Boddington has installed Polysius HPGR’s and I read that the new owners of Mt Todd (after a few prior owners failed to make a profitable operation) are now finally planning to use HPGR’s in the proposed new flowsheet.  Prof Klaus Schonert’s original German patent No 2 708 053 was granted in 1979. The Boddington installations are deemed now by many as the start of the acceptance of HPGR’s into main stream mineral processing flowsheets. That is 31 years after the granting of the first patent. Most international patents only last somewhere between 17 and 22 years.
So why has it taken almost a working life time before HPGR’s have even started to be accepted in the minerals industry?  The technology surely must be the most important “new invention” patent in our industry for the last 100 years. A Supreme Court judge in the USA said as much in upholding Schonert’s patent in an infringement case in the 1980’s. It perhaps matches the inventions of the Polaroid camera or Xerox photocopier in other industries.  Any serious research into the technology by a competent metallurgist or engineer over the last 30 years should have convinced most of the operating and cost benefits of including HPGR’s in a circuit. So why aren’t they everywhere?
In their plenary paper at the 1992 Extractive Metallurgy of Gold and Base Metals conference in Kalgoorlie Norm Seaton and Robin Batterham essentially précised general marketing theory that represents the forces that inhibit the implementation of new mineral processing equipment, technology and processes into the form of a probability equation.
P          =          R  x  N  x  (CC)/(CP)
P is the likelihood that a new process will be installed
R is the size of the reward if the new process is successful
N is the number of similar applications of the process in this industry
CC is the size of the company doing the purchasing
CP is the capital cost of the new process
This equation indicates, amongst other things, that if N is a very small number (or zero) then success in our industry requires exceptional circumstances.
So what were the real barriers to HPGR’s in the minerals industry?  Those who know a bit about them will know that they were immediately and rapidly accepted in the cement industry with the first units installed in 1985 and then with over 300th machines already installed by 1992s. This tells you that the nature of the industry and criteria for their use in cement manufacture is very different to their use liberating minerals. One point that is interesting to note is that the first two installations were paid for by German and EU government grants to help with the development of new technology. This took care of N = 0 in the above equation in that industry. Cement is a commodity of generally local supply in a competitive market place with relatively small margins. The vast majority of the production costs relate to energy. So when these first plants had success in dramatically reducing their grinding costs by the introduction of the HPGR’s it gave them a competitive advantage. The competitors simply had to follow suit and install HPGR’s or be forced out of the market. The cement industry is characterised by having a small number of large international corporations having equity and controlling operations world-wide. Also, in building cement manufacturing plants, three major engineering companies at that time had probably 95% of the market for supplying turn-key plants. All this led to a remarkable diffusion of knowledge, take-up and acceptance of HPGR’s world-wide.
Contrast this to the nature of the mineral processing industry where any number of engineering, consultancy or equipment supply companies compete for the right to design or engineer or even build the process plant. No diffusion of knowledge or interest to take the lead here.
There are many macro and micro issues as to why take up was quick in cement and slow in mineral processing - too many to go into detail here. One of the major reasons put forward for the very slow adoption of HPGR’s in the minerals industry has been the more abrasive nature of minerals. This consequently let to the much higher wear rates on the early type of hard facing used as a wear protection and therefore low machine availabilities. This was the case in the early years but in reality, even with these issues, the economic benefit and technical advantages of HPGR’s would still easily have made it worthwhile to install instead of the norm equipment. The development of the stud lining (and then other similar wear surfaces) in 1993 negated this issue, but again, that was 17 years ago.
There was in fact some limited use of HPGR’s in mineral applications in the early days. Two examples are the liberation of diamonds from kimberlite (without breaking diamonds) and iron ore pellet production where the ability to reduce blaine values, increase green pellet strength and decrease porosity of the pellet offered a huge advantage to producers, pushing them over the tipping point where the risks of the unknown were outweighed by the advantages (big R in the above equation).
The biggest inhibitor in embracing and benefiting from the development of technology like the HPGR’s is the structure of our industry itself. The builders of mineral processing plants are firmly divided into two camps. One is the group of large multi-national mining companies that makes profits from the sale of its products based on the efficiency in which it mines and processes these products. This should be the group embracing the use of cost effective improvement in technology and processes. However, despite top down mission statements and visions for efficiency and cost improvements in these companies and large funds dedicated to R&D, focused research and process improvements etc. it is very difficult to get new technology approved. These companies can have a multi layer of stakeholders protecting their personal vested interests in their area of domain. With this they can highlight all the potential risks and fatal flaws whether real or imaginary. For all the positive people, it only takes one dissenting voice to obtain a negative decision. The second group is the small and medium size cap companies on the various stock markets around the world. I would suggest that when ever they get in the position of having to develop a mine and build a process facility the focus of the controllers of these companies is more about maximising the current share price (and getting out?) than building the most cost efficient plant for the future. They mostly could not care less about the possible benefits of any new technology.
Having said the above about these two groups I must say that you have to accept both positions as the nature of the business. This makes it hard for new technology. There is hope in a small number of companies that have managed to grow to a sustainable size but have not yet lost the capability to implement new ideas. This really is the very small target market for new technology developers.
In 1994 I wrote a business plan for the introduction of the HPGR into the minerals industry “A Strategy for the Future”. Despite at the time having all my new found knowledge on the theory of innovation and new technology it is slightly embarrassing now to see that I had extrapolated that there would be 99 sales of HPGR’s in the minerals industry in 2010! In my defence it was based on the assumption that the company for who it was written would instigate recommendations to accelerate the up-take, such as assisting with demonstration installations on operating mines and other measures which were not acted on.
It is interesting to note that the current workhorse of our industry – the ball mill – also initially struggled. After the first one was installed in Germany in 1876 it took about 15 years for anyone to see the real benefits and before the second mill was installed in the industry.


  1. Hi Michael, interesting blog. You make many good points but in the case of HPGR there are many hurdles to be overcome including that, for example, it is often more capital intensive and more difficult to operate than SAG based technology and there needs to be a significant operating cost savings to achieve reasonable payback. For many ores it isn't there. Chris Morley and I wrote a paper that was presented at the 2010 CMP if you are interested.

  2. Interesting article.

    A very similar "one-generation" lag occured with column flotation cells. On the other hand, there was such a rapid implementation of the high gravity centrifuges in the gold industry to the point that some projects were executed without proper assessment of the applicability of the technology to the feed being processed.

    Having only general familiarity for the cement industry I can imaging that rapid implementation of HPGRs throughout this industry was due to very tangible benefits. The feedstock for all cement plants is essentially the same and there is also great similarities for the process flowsheet. Measureable OPEX cost reduction (power, wear parts, optime) appears to have been the driver.

    In the case of high gravity centrifuges in the gold industry, the feed stock contains some coarse grained metallic gold (gravity recoverable) or none (refractory gold ore). Once the distinguishing key parameter for successful implementation was identified, then it became a matter of fact.

    Maybe if there is another example of technology which rapidly spread to a segment of the mining and minerals industries one could identify if there is a trend?