Thursday, 25 May 2017

We welcome Cheminova as a sponsor of Flotation '17

Danish company Cheminova, who is sponsoring MEI's flotation series for the 4th time, was established in Copenhagen by Gunnar Andreasen, a chemical engineer, in 1938.
The company has grown to become an important manufacturer of plant protection chemicals, chemical intermediates, and flotation chemicals.

In 1953 Cheminova moved its manufacturing plant to its present western Jutland location on the Rønland peninsula between the North Sea and the Liim Fiord. Because elemental phosphorus and sulphur raw materials are delivered directly to the plant, Cheminova’s manufacturing is completely vertically integrated and provides Cheminova considerable infrastructural advantages, which have been an important factor in its growth. Additionally the location allows it to effectively manage costs, final product quality and responsiveness to customers.
Cheminova has become a well-established leader in the production of organophosphate reagents and chemicals, the flotation chemical product line being a very important product line extension to its agricultural chemicals because the dithiophosphate phosphorus-sulphur chemistries are quite complementary to the agriculture chemicals, which are also phosphorus and sulphur based.
A wide range of flotation dithiophosphate reagents are produced in acid and aqueous solution forms, the latter using sodium, potassium or ammonium hydroxide for neutralization. To ensure that the products provide the best possible mineral processing circuit performance, Cheminova has developed dithiophosphate mixtures and mixtures of dithiophosphates with mercaptobenzothiazole and thionocarbamates that have been tailored for the rigorous needs of the mining industry.  In order to provide a full complement of flotation reagent products, Cheminova also supplies some frothers.
Current Flotation '17 sponsors

Monday, 22 May 2017

Flotation '17- Final Call for Abstracts

A reminder that if you would like to present a paper at Flotation '17 in Cape Town in November, short abstracts should be submitted by the end of this month.
Networking at Flotation '15
This is a great opportunity to meet all the leading players in the flotation field, and also to have your paper considered for a special flotation issue of Minerals Engineering.
As always the conference will have an associated exhibition, and the dinner this year will be held at the Lagoon Beach Hotel, with its classic view of Table Mountain.
Process Mineralogy '17 conference dinner at Lagoon Beach Hotel
More information can be found on the posting of 10th April.

It is now widely accepted that this series of Conferences are 'must attend' events for both flotation researchers and practitioners. The great value of attending the Conference is that it provides an excellent forum for an exchange of views among those doing more fundamental research and those from industry who are able to share their successes and challenges with the audience. This is why the Conference makes such a valuable contribution to the practice of flotation...
Prof. Cyril O’Connor, Chairman, International Mineral Processing Council


Friday, 19 May 2017

May's Cornish Mining Sundowner on the north coast

Due to other commitments last night was my first Cornwall Mining Sundowner since January. Our normal summer haunt, Falmouth's Chain Locker is currently undergoing extensive renovation, so for the foreseeable future the sundowner venue will be shunted around west Cornwall.
Last night's meeting was in the north Cornwall village of Portreath, in the Portreath Arms Hotel, with a busy bar which just about managed to accommodate the 20+ regular sundowners, and a few new faces.
The mineral processing contingent was made up of myself, and my old CSM colleague Tony Clarke, as well as Nick and Flee Wilshaw, of Comminution '18 sponsor Grinding Solutions Ltd, and Dave Goldburn, formerly with SGS Minerals Services. SGS recently abandoned its UK operation in Cornwall, and Dave is now Operations Manager with Physical Separation '17 sponsor Holman-Wilfley. I look forward to seeing both Nick and Dave at Physical Separation '17 in 3 weeks time, when our usual first evening coastal path walk will this year end with drinks at the Quayside Inn, rather than our familiar Chain Locker.
Nick, Barbara, Tony, Dave, Flee and me
Twitter @barrywills

Thursday, 18 May 2017

Sustainable Minerals special issue published

Volume 107 (June 2017) of Minerals Engineering is now available on ScienceDirect, and contains 14 selected papers from Sustainable Minerals '16, which was held in Falmouth, Cornwall last June, including a very timely and thought-provoking keynote paper by Prof. Robin Batterham on the mine of the future. The conference proceedings, containing all the unrefereed papers, is available on USB from MEI Online.
Sustainable Minerals '18, MEI's 5th conference in the series, will be held in Windhoek, Namibia in June next year, back to back with Biohydromet '18.
Twitter @barrywills

Monday, 15 May 2017

Flotation- it's a lot older than you think!

In my posting of 10th April I commented on the fact that, although the 'invention' of flotation is often attributed to Francis Elmore in his patent of 1904, there was much interest prior to this, particularly in Australia, as there was a desperate need to develop a process which could be used to concentrate base metal ores, as gravity concentration was becoming impractical as the ores became leaner and more complex.
Amongst the comments on the posting was a very interesting one from Dr. Martin Rudolph, of the Helmholtz Institute Freiberg for Resource Technology, Germany, who  advised that the flotation process will in fact celebrate its 140th birthday on July 2nd this year!
It was on that day in 1877 when August and Adolph Bessel patented the first flotation process related to the beneficiation of graphite from a mine in south east Germany, which is still in operation today, currently operated by Graphit Kropfmühl GmbH, part of AMG Mining AG.
Martin has procured a copy of the 1877 patent and has kindly translated it into English:

Patent 1877 - No 42 – Class 22 Bessel Brothers (August Bessel and Adolph Bessel) in Dresden, Germany

Process for refining Graphite

Patented in the Deutsches Reich (German Reich) beginning July 2nd 1877

The crude impure graphite is mixed with a small quantity (1 - 10 pCt) of an organic substance which, when liquid, is not water-soluble or only slightly miscible, when solid, is neither dissolved in or wetted by water. These substances, as far as they can be practically used, are as follows:

1. All the fatty oils and rigid fats of the animal and plant kingdoms, and the fatty acids which can be obtained from them,
2. All etheric oils,
3. All the resins of the vegetable and mineral kingdom, their dissolutions, and the oils which can be obtained from them by dry distillation,
4. The rubber bodies, their dissolutions, and oils which can be obtained by dry distillation,
5. The so-called balsams of commerce,
6. Crude and refined petroleum, the by-products of refining, both the more volatile ones, such as ligroine, petroleum alcohol, and petroleum ether, as well as the less volatile, the so-called volcanic and engine oils,
7. Tar of brown coal, hard coal, wood, and peat, as well as the oily products of the distillation of these tars, as well as the residues remaining during their distillation,
8. Pitch of the trade,
9. Paraffin,
10. Gasoline,
11. Potato fusel alcohols,
12. Beeswax and vegetable waxes, as well as all oils obtained from those by dry distillation,
13. Shale oils and tar from sands,
14. Ozokerite,
15. Whale fat and whale oil,
16. Oils of bones obtained by dry distillation, as well as boiling out bones,
17. Cheese types of the trade,
18. Any mixtures and dissolutions of the bodies listed above.

The mixture of the graphite with the chosen body is made as intimate as possible so that all parts of the former come into contact with it. The mixture is then poured into water and the latter is heated until vigorous boiling. During this cooking the flakes of the graphite are observed to rise within the liquid while the earthy substances (clays) remain on the ground. The graphite floating on top is drained off and dried. If the graphite is simply boiled with water without prior mixing with any of the substances mentioned, such separation does not take place, nor is this done by desliming. The operation proceeds preferably with the flaky varieties of graphite.
Thanks for sharing this with us, Martin. We look forward to seeing you and your team in Cape Town in November for Flotation '17, and hopefully your translation might lead to some interesting ideas on 'new' reagents!

Saturday, 13 May 2017

Brief encounter in a cold and wet Trebah

Trebah Gardens, on the Helford River, just outside Falmouth, is one of Cornwall's great gardens, and is rated in the top 80 gardens in the world.
Trebah in late summer (source unknown)
Unfortunately it was not at its very best yesterday, however, as it was unseasonably cold and wet, but Barbara and I took the 15 minute drive to catch up with Roger and Janet Thomas, and Rod and Kathy Whyte, who we had met up with just over a year ago in Cape Town to reminisce about our Zambian Copperbelt experiences (posting of 19th April 2016). The four of them are on a cruise around the British Isles, and this morning visited St. Michael's Mount in Marazion (posting of 18 October 2010), before being coached to Falmouth for their Trebah experience.
Roger, Janet, Kathy, Rod, Barbara and me in a very wet Trebah
No matter what the weather, the walk through the Garden, with its rhododendrons, magnolias and camellias, onto Trebah beach is spectacular, and the beach at the bottom of the garden is an idyllic spot on the Helford River. In 1944, the beach was used as an embarkation point for a regiment of 7,500 of the 29th US Infantry Division for the assault landing on Omaha beach, part of the D -Day Landings.
An artist's impression of Trebah Beach, 1944
As I pointed out to Roger and Janet, the weather in Cornwall is as capricious as that of Cape Town, and for their benefit, this is what they might have seen on the beach if the weather had been a little better!