Knelson Concentrators: A modern mining legacy

There’s a reason why Knelson Concentrators is a household name in the global mining industry. Quite simply, Knelsons are the best gravity concentrators that money can buy, and always have been. Not only are they more efficient at recovering gravity recoverable gold (GRG), other free-milling precious metals and many other heavy minerals, but they also have a lifespan in excess of 30 years when maintained correctly. This is why Peacocke & Simpson has always sworn by Knelson Concentrators, and always will. But just how did Knelson Concentrators come to be? What made them better at gravity recovery than anything else on the market? And how did the Knelson brand come to be such a dominant force in the mining industry?

In the mid 1970’s, Benjamin Virgil (Byron) Knelson, creator and founder of Knelson Concentrators, found himself working in a placer gold mining operation in the Yukon. With a background in excavation and previous mechanical maintenance (on everything from cars to agricultural machinery in his family business in Bladworth, Saskatchewan as a boy), Byron observed the methods used to recover gold and believed that he could do better. He could. Having spent a whole five days on the plant, Byron knew that he could build a device that could more effectively recover the fine particles of gold that were routinely carried off the end of the sluice boxes in a torrent of water. Byron was the first person to run a fluidised feed into a centrifugal concentrator to stop the concentrate from continually packing. He used to tell the story, with much laughter, of how he had his epiphany during the quicksand scene in an old Tarzan movie. Regardless of how he came about it, and little to his knowledge at the time, Byron Knelson was about to change the face of the gravity concentration industry forever.

In 1976 he tested the first prototype of what would come to be the best known centrifugal concentrator in the world. The product spoke for itself with the results achieved, and with some mechanical fine-tuning the Knelson Concentrator was born.

Knelson Concentrators outshone any and all predecessors in recovering precious metals, and set the standard in the gravity concentration of free-milling gold and platinum. Essentially, the concentrator is a centrifuge that combines enhanced gravitational force with a water injection process to create a fluidized concentration surface into which fine gold grains (due to their high specific gravity) can penetrate and become trapped. The original device operated at 60 G forces, and 30 years later extensive research has proven that for 90% of traditional gravity gold applications, 60 G’s is near optimum.

In addition to being a pioneer and a creative thinker, Byron Knelson was the most likeable man one could hope meet, and an outstanding businessman. He believed that if you took care of your clients, and continued to give them more than they expected, business would take care of itself. With this remarkable character and a revolutionary design, it wasn’t long before mining companies far and wide became familiar with the Knelson concentrator.

In 1984, a year before Peacocke & Simpson’s inception, Kevin Peacocke sat at his desk with a black and white Photostat copy of a new, supposedly revolutionary device in front of him. Apparently, this intriguing, square washing machine on legs, with no fins or flashing lights to speak of, could recover free gold extremely well, and Kevin’s director wanted him to look into it. Nothing came of it at the time, but as the years passed the idea of this machine niggled at him.

Then in 1988, the Chamber of Mines sent a few lucky metallurgists, Kevin among them, on a tour of Canada to expose them to new technologies. They were to meet various companies and counterparts in the hope of forming business relationships and exchanging concepts. Upon arrival in Val d ‘Or Quebec, there was a reception dinner for the foreign and local counterparts. To break the ice games were organized, one of which was racing remote controlled cars around all the tables. Kevin’s partner was a large, burly man with a beard who looked somewhat like Father Christmas, and he immediately admitted that he crashed even the big cars, and as such Kevin was to be the driver. They fared quite well, and as they were about to part ways the man asked if Kevin would be willing to assist him in demonstrating his machine to a customer at a nearby gravel pit the following day. “Of course”, Kevin said, and subsequently lugged buckets to and fro and did all the hard work whilst his new friend spoke to the client. The machine in question was now cylindrical, not cubic, and had a ‘K’ logo proudly displayed on its green exterior. Sure enough, it caught plenty of free gold and the client bought it. The big fellow was none other than Byron Knelson, and he and Kevin remained teamed up for the rest of the trip. In parting, Kevin asked if he could represent Byron back in Zimbabwe, and if so if he could have a small Knelson Concentrator to demonstrate with. “Yes, you can represent me,” Byron said “and no you can’t have one, you must buy it”. This was quite an ask for a small operation in Zimbabwe. Knelsons weren’t cheap, for good reason, and after weighing the options Kevin knew P&S had to have one.

In 1992 Byron made his first of many trips Zimbabwe, at a time when the country happened to be going though economic turmoil, with supreme interest rates, no infrastructural development, and so on. As a result, Peacocke and Simpson had sold only a handful of small concentrators since Byron and Kevin’s meeting, and it looked very much as though Byron was actually visiting to relieve P&S of its agency. He and Kevin, however, went on a countrywide tour of the mines, and Kevin quickly learned from the master salesman himself. The chief lesson being that price is not an object when compared to value of output and a payback period of months or even weeks. As an example, a meeting was arranged with the managing director of Zimbabwe’s largest privately-owned gold mining company, which at the time was trialling a copycat Knelson on its flagship mine.  Byron was asked why his machine cost so much more than the copycat, to which he replied “tell me, Morris, what car do you drive?” When told it was a Mercedes, he then said “Well, as you know a Nissan will go the same places, just not as fast, efficiently or reliably. You’ll get there most of the time, but not all of the time, and it’ll be a slower and less comfortable ride”.  It seems that did the trick, because Morris agreed to try a Knelson. On Byron’s next visit to Zimbabwe he again met with Morris, who confessed: “Byron, you’re absolutely right, a Mercedes is way better than a Nissan”. He subsequently installed more Knelsons and convinced many industry colleagues to do the same, and became a personal friend of Byron’s and a champion of Knelson Concentrators.

After Byron and Kevin’s trip, P&S put their laboratory Knelson to work and started creating reference installations, such that in many cases the machines sold themselves, and by the time Kevin Peacocke and Pete Simpson attended the first Knelson Agents Conference in Vancouver, in 1995, their agency sales were second only to ConSep of Australia.

Byron had by now adopted Kevin and Pete as his “blue-eyed boys”, and he was at pains to ensure that they spent much time with Brett Knelson, Byron’s son and head of engineering, and Doug Corsan, Byron’s son-in-law and head of sales. Back in ’95, Brett and Doug were busy growing the company from being a smallish family business with out-house manufacture to being a self-sufficient and fully equipped, world-class, specialist equipment manufacturer accepted by all major process engineering houses.

Kevin, Pete, Brett and Doug had much in common, and formed close bonds and friendships that last to this day. On the back of the strong and technically well-supported sales in Zimbabwe, P&S’s coverage was expanded in 1996 to include much of Central Africa, and in 1997 they were invited to assist with setting up an office in South Africa, originally Knelson Concentrators Africa, now Gravity Concentrators Africa. In 2002 their coverage was expanded yet again with the brief to provide technical and after-sales support throughout Africa, from Cape to Cairo and Dakar to Djibouti.

After his first trip to Zimbabwe in 1992, Byron fell in love with Africa, and visited Zimbabwe another six to eight times, even chose to bring his second wife to Harare for a wedding ceremony after their civil marriage in Vancouver.

Peacocke & Simpson’s role on behalf of Knelson in Africa now includes extensive GRG and EGRG testing of samples from throughout the continent (and beyond), technical support on gravity circuit design and tendering processes, supervision of installation and commissioning of machines, and after-sales support. P&S staff frequently travel Africa to carry out circuit audits and machine inspections, re-training of operating and maintenance staff and circuit optimisation.

Both Kevin Peacocke and Pete Simpson sit on the Knelson technical board, and the P&S laboratory carries out a significant amount of R&D on behalf of Knelson. On many occasions in the past Kevin has been contracted to provide advisory and agent-training services beyond Africa, principally in Russia and South America.

The combination of world-leading equipment, over 25 years of Africa-wide experience and a sincere desire to have the happiest customers on any mine site makes Knelson and P&S a winning team. In the words of the great man himself: “The key to our success is remarkably simple. If you give the customer more than he expects, business takes care of itself.”

In the years to follow, Knelson Concentrators would continue to grow, improve, and pioneer the gravity concentration industry. In 1992, the simple batch concentrator – that required concentrates to be rinsed out by hand – took a huge leap forward. The concentrate harvesting process was automated by means of a Centre-Discharge feature, allowing the technology to diversify from small alluvial operations into large hard-rock processes. It was around this time that the success and ingenuity of the Knelson attracted pretenders to the throne and copycat machines, some very blatant and others subtler, but Knelson remained the clear leader and is still so today.

One of Byron’s favourite sayings was “Unless you’re the lead dog the view never changes”, and he and his team made sure that their innovation and R&D spending kept them out front.

If you would like to know more about how the efficiency, design and robustness of the Knelson machines make them better than all other high-G concentrators, see our previous article; 5 Reasons why Peacocke & Simpson swears by Knelson Concentrators.

The success and ingenuity of the early Knelson not only made it the industry standard that is incorporated into nearly all gold plants and greenfields projects, but also attracted academics who very quickly cottoned on to the fact that this machine was going places and was going to revolutionise gold recovery. Chief amongst these was the late Prof. Andre Laplante of McGill University Montreal, who became a close personal friend of Byron and dedicated his academic career to the research and development of gravity recovery. Long before his untimely death while cross-country skiing, Andre was recognised worldwide as “Mr Gravity”. He developed the GRG and EGRG test procedures, which are recognised standard tests, and which Knelson Concentrators then used as the basis to develop their KC-MOD*Pro circuit simulator.

GRG, EGRG and modelling now allow fully informed decisions about gravity processing, and allow plants to be designed for optimum performance and cost/benefit considerations well in advance of casting first concrete at a new mine site. The Knelson group has literally hundreds of GRG and EGRG results in its database, and has developed modelling to the point where simulations can often predict plant recovery to within one percentage point.

The mantle of “Mr Gravity” has fallen upon FLSmidth’s (formerly Knelson) Mike Fullam who has now analysed more GRG, EGRG and KC-MOD*Pro data, and conducted more on-site plant audits, than even the Late Great Andre Laplante. There is no-one alive right now who knows more about gravity recovery than Mike, and he remains a huge and loyal Knelson asset.

As time progressed, Byron, with the help of Brett Knelson and Doug Corsan, grew Knelson concentrators from a world-class, specialist equipment manufacturer to a global mining powerhouse known primarily for customer satisfaction and its dominant market share.

In 2000, Knelson introduced their line of continuous variable discharge (CVD) concentrators, suited to applications where higher concentrate mass yields are desirable. These applications include the recovery of high specific gravity minerals such as tantalum, cassiterite, chromite and iron ore; the pre-concentration of coarse sulphide minerals and the scavenging of tailings streams.

In 2010, Knelson further expanded its repertoire by partnering with South African company Deswick International to offer milling and fine-grinding solutions (Knelson Milling Solutions), in addition to opening its Knelson Processing Solutions (KPS) branch offering full turnkey recovery solutions.

These are but a few of the milestones achieved by the mining legend, but suffice in demonstrating Knelson’s continual drive to enhance and improve its technologies and client offerings. To date, Knelson has the largest market share of gravity concentrators, with roughly 3,000 machines spread across the globe, approximately 400 of which have been installed in Africa.

By 2010, Knelson Concentrators had become so successful that it entered into negotiations with FLSmidth, to further expand the operations of Knelson, whilst also taking care of his loyal Knelson Concentrators brethren. After a year of negotiations, on 29 August 2011, Byron passed away, succumbing to his struggle with cancer. Unfortunately, he was unable to see the sale to fruition, with the acquisition being finalised on 19 September, just 21 days later. However, he left behind a legacy that will last for decades to come. In his honour, Byron’s son, Brett, and son-in-law, Doug, set up the Byron Knelson Memorial Scholarship. Byron Knelson was a father, brother and friend to  many of his Knelson agents around the world and will forever live on in the lives of those he touched, inspired and mentored.

For close on 40 years Knelson Concentrators have lead the world in gravity concentration of metals and minerals. Names have changed but most faces – of employees and agents – have stayed, and the strengths that made Knelson great remain intact. With vast and long experience now further supported by the extensive global resources of FLSmidth, the future is bright, and the lead dog forges ahead.