SEPARATION
Recovery at FLSmidth , said : “ The new Knelson GX Concentrating Cone is the culmination of over 40 years of research and operational experience and is exciting news for our customers . It delivers a win-win-win scenario : better recovery , less water use and less downtime due to easier maintenance . “ In short , it helps customers produce more with less resources – a central tenet of our MissionZero ambition to cut water and energy waste in mining by 2030 .”
Sepro looks to eliminate water consumption
Canada ’ s Sepro Mineral Systems is developing a new gravity concentrator that eliminates water consumption during gold recovery processes . The current Falcon SB Gravity Concentrator , which recovers precious metals like gold , flips between periodic run and rinse cycles . It is the most common unit used in gold processing within grinding circuits . The SB is a “ Semi-Batch ” unit , meaning it continually accepts feed during a run cycle , but only produces concentrate during periodic rinse cycles . The cycles last from five minutes to several hours , depending on the application .
“ While process water consumption for this machine is already low , we ’ re challenging ourselves to find a way to maintain high levels of gold recovery while eliminating any need for excess water . This will improve mill circuit
COMMINUTION ‘ 21
19-22 April , 2021 | Online
Sponsored by : King ' s Ceramics & Chemicals , Starkey & Associates , Russell Mineral Equipment , Keramos , Grinding Solutions , Glencore Technology , ME Elecmetal , Derrick Corp ., ZEISS , Hudbay Minerals , Magotteaux , Metso : Outotec , Sino Grinding International , Maelgwyn Mineral Services , CEEC , International Mining , Imformed & Critical Minerals Association
BIOMINING ’ 21
7-9 June , 2021 | Online
Sponsored by : AFX Mixing & Pumping Technologies , Newmont , International Mining , Ocean Mining Intel , Cornwall Mining Alliance & Critical Minerals Association
SUSTAINABLE MINERALS ‘ 21
21-23 June | Online
Sponsored by : FLSmidth , International Mining , Cornwall Mining Alliance , CEEC & Critical Minerals Association performance and reduce the amount of water that needs to be removed later in the process .”
The Falcon C and UF models already require no fluidising water to operate . The C model is used to improve the efficiency of gold recovery
FLOTATION ’ 21
8-11 November , 2021 | Hybrid or Online
Sponsored by : Promet101 , Maelgwyn Mineral Services , Magotteaux- Gold Ore , CiDRA Minerals Processing , Hudbay Minerals , Senmin , Clariant , BASF , Eriez , Nouryon , Festo , International Mining & Critical Minerals Association
www . min-eng . com / conferences /
operations or as pre-concentration devices ; while the UF tackles gold ores which contain carbon that can interfere with the leaching process . Flotation is used to remove the carbon before leaching . However , during the flotation process , extremely fine gold particles will float with the carbon . This gold would normally be lost to tailings , but the UF has the power necessary to recover the gold from this carbon-gold slurry .
“ Those familiar with the use of Falcon or the Knelson concentrators for gold recovery know that the units require quite a bit of fresh water to operate . As such , Sepro has had a project going on for a while now to try to eliminate the need for additional water in these batch concentrators . There have been some very good results using a particular mechanism for concentration that does not require water and the Sepro team is working on mechanically scaling that up to the industrial units .”
Another study has been examining bowl
Canada ’ s Sepro Mineral Systems is developing a new gravity concentrator that eliminates water consumption during gold recovery processes
profiles and seeing if there is something that can be done to improve recovery by changing bowl profiles .
A second research project Sepro has in the works is a gravity separation computer simulation model . When this model is completed , it says it will be able to perform R & D and technology development on a computer rather than building circuits and running experiments . “ Lab experiments are costly and time-consuming . Once the model is complete , we ’ ll be able to do our development work via computer . It will be the first time anyone has developed a model capable of performing these specific tasks to improve operations . The model is one of a kind and our research will allow us to capture the physics and flows of fine mineral slurries with applications for large industrial machines as well as pilot-scale equipment .”
Finally , away from gold , many of the high specific gravity minerals of interest are friable ( eg tin ores cassiterite , wolframite ) and excessive fines are generated in the grinding / comminution circuits which cannot be recovered with conventional gravity equipment like spirals and may be lost directly to the tailings stream . “ Recent developments in centrifugal gravity separation equipment specifically designed for fine or ultra-fine particle separation and recovery have resulted in heavy mineral particle recoveries as fine as 10-20 microns . Ongoing research work has also identified the benefit of closed-circuit , multi-stage gravity recovery circuits using some combination of centrifugal concentrators and conventional equipment ( tables , spirals , flotation etc ) which can substantially increase overall plant recovery and final concentrate grade .”
IM
APRIL 2021 | International Mining 51