One hundred and twenty one abstracts have been approved for the upcoming conference Paste2014. The conference will be held in Vancouver September 8-11, 2014, and a record attendance is anticipated. Here, to whet your appetite and encourage you to come, is a review of some of the abstracts and papers that will be presented.
In the catch-all category of Miscellaneous there nine abstracts. The most fascinating to me is Field farming trials of bauxite residue. Hongyu Li of Rio Tinto Alcan in Australia in his abstract undertakes to tell of what appears to be a well-planned and meticulously executed series of field trials using a rather strange pieces of equipment to mud-farm and hence dewater soft tailings. The idea is that a series of blades cut into the soft tailings forming channels for the water to run off. He notes this works only once the tailings has an initial strength of 15 kPa. I have noted that polymer amended oil sands tailings display the same behavior: once they reach a strength of about 15 kPa you can windrow them into piles of clods and this promotes drying. Maybe Li’s paper will encourage trials of his equipment on the oil sands.
The paper that promises most is The influence of Rheomax ETD chemistry on the de-watering rate and resulting rheology of tailings by Stephen Adkins of BASF Performance Products. He and his coauthors in their abstract promise this:
BASF patented Rheomax® ETD technology has been developed to achieve a greatly improved disposal process. Polymer is applied in order to bind all the solids in the tails slurry together in order to greatly increase the yield stress of the material. As a result, when the slurry is discharged into the tailings disposal area, all the solids are immediately immobilized such that they are deposited with the required angle of repose, tailored to the storage facility requirements. This allows the water to rapidly drain away through the action of gravity from the highly porous mass.
If the product is as good as noted here, we have a whole new highway opening up for efficient management of polymer amended tailings.
Of course we will have to get the beach profiles right. There are nine abstracts on this topic promised for Paste2014. The great minds will once again gather and debate their various, conflicting theories and technical methods of analyzing and predicting beach profiles. Tim Fitton and Gordon MCPhail are joined in this great unknown by Paul Williams, Keith Seddon and Andy Fourie. Personally I think they are all still getting it wrong and should approach the problem as does Hansjorg Seybold in his great book Modeling River Delta Formations. Sadly he won’t be at the conference. Still it will be an interesting debate.
Oil sands tailings has twenty-six abstracts. If you are involved in the oil sands industry you must attend. The Suncor team of John Zhang, Alan Melanson, Adrian Revington and Sean Wells promises a paper Mechanical dewatering of Suncor fine tMFT oilsands tailings. Keep in mind this is the team that literally invented the process of polymer amendment of tailings. And keep in mind that until now we have read almost nothing of their work in the open literature. So this is a very important and welcome paper.
With Adrian Revington, Gordon McPhail, and Lawrence Charlebois, I have almost finished writing a paper on Optimized Seasonal Deposition of tMFT. I believe that this is the way to go with flocculated oil sands tailings: in spring place a layer to be consolidated by subsequent lifts; in summer place thin lift that dry in the sun; and in fall place a thick layer that freezes and thaws and hence gains strength. I have no patience with the sole focus on this lift drying. There is just too short a summer in Fort McMurray to make this practical.
Filtered tailings have eight abstracts. That deyon of mining geotechnical engineering, John Lupo of Newmont Mining Company along with Marcelo Musse, a consultant in the USA have an abstract for a paper entitled Converting slurry tailings facilities for dry stack – two case histories. That is sure to be a great paper and a pointer to the future—for I suspect that filtered tailings is the way to go, in spite of the protestations of the thickened and filtered tailings priests.
The Carlos Cacciuttolo of ARCADIS in Chile has a paper Filtered dry stack tailings: development and new trends. I got to know Carlos in Chile and I can attest that while still very young, he is an amazing engineer and will I predict become one of the leaders of tailings in the future. Come listen to him now as he develops and advances.
In spite of the name of the conference, the topic of paste tailings has attracted but eleven papers. The titles of these papers tells you why there is an apparent waning of interest in the topic:
- Problems in designing a paste system by Stephen Slottee of WesTech Engineering
- Assessment of postliquefaction strength of paste type materials and its influence on the design and operation of tailings impoundments in the Andes Region by Jorge Macedo of the University of California Berkeley.
Thickened tailings has twenty nine abstracts. Jeremy Boswell of Thurbers in Calgary leads the pack with his usual oversight paper on Thickened tailings – operational challenges and remedies. I particularly look forward to the papers from those practical and experienced engineers and their papers:
- The influence of feed properties on cyclone performance and stacking of underflow by John Wates and colleagues of Fraser Alexander in South Africa.
- Dewatered tailings surface disposal trade-offs — a case study by Don Poulter and Sue Longo of Golder Associates.
Finally we land at the session on Backfill where there are fifteen papers. The best title is Successful recipes for mine paste backfill by Corina Aldea and Kevin Connolly of AMEC. Another good succinct title is Selection criteria for backfill systems by Mark Groulx and John Haan of AMEC and Kennecott respectively. And finally rounding off a category characterized by papers of short tile yet long impact is Multiphysical characterization of cemented paste backfill by Mamadou Fall and Alireza Ghirian of the University of Ottawa.
There promises to be at least one and probably many papers of interest to you, whatever you are doing in mining and tailings. There promise to be many papers that will challenge our thinking and advance our practices. I know I will learn a lot. So join us.