FLOTATION
BGRIMM KYF-130 and XCF / KYF-30 forced-air flat layout flotation cells at RAKITA ' s Timok in Serbia
having been reduced by 20 % at 0.5 kW / m 3 power strength , and coarse particle recovery rate increasing by 10 %, while the overall recovery rate increased by approximately 2 %.
Also in China , as part of a process plant upgrade and expansion from 14,000 t / d to 24,000 t / d by China Molybdenum , and taking into consideration the original plant footprint space restrictions , BGRIMM provided a compact KYF-300 m 3 configuration , replacing the previous 10 70 m 3 self-aspirated flotation cells , five 160 m 3 cells and two 4.5 m by 10 m flotation columns . Consequently , the + 0.15 mm molybdenum recovery rate was significantly increased by 2-3 %.
In introduction of new technology , a combined configuration of backward cambered-surface blade impellers and backward flat blade impellers was developed and utilised in the expansion of the Yinshan lead-zinc mine and Chengmenshan copper mines of Jiangxi Copper Corporation . The recovery rates of chalcopyrite and pyrite were both increased by 1-2 %.
BGRIMM has also developed a new HIF series of cells . It told IM : “ We have realised remarkable technical progress in recovery improvement of coarse particles . Metso Outotec , FLSmidth and BGRIMM have all developed 300 m 3 and even larger flotation cells in succession , yet the scale-up of tank volumes also leads to further distance between the impeller and overflow lip , which then results in a distant upward pathway for mineralised bubbles . BGRIMM was aware of this problem years ago and has been studying the various outcomes for the impeller to be set at different heights inside the tank . Accordingly , we have established a model covering the relationship among different mineral species , particle sizes and locations of the impeller from the tank bottom . Based on this , HIF series flotation cells were developed , with a volume range from 50 to 320 m 3 .”
The transport distance is flexibly adjusted according to certain flotation dynamics of various processes . HIF flotation cells can work independently or be combined with KYF flotation cells . This technology has been applied at the HBIS-owned Palabora Mining Company copper
mine ( 38,000 t / d ) in South Africa , the Shaxi copper mine ( 10,000 t / d ) of Tongling Nonferrous Metals Group Holdings , the Taibai gold mine ( 4,000 t / d ) of China National Gold Group Co Ltd and the Longnan Zijin gold mine ( 10,000 t / d ) of Zijin Mining .
In respect of improvement of fine particle recovery , BGRIMM said its applications have been proven in phosphate and ilmenite operations . “ Due to the price rises of raw materials , a host of mining enterprises are proposing to recycle the micro-fine P 2O 5 and TiO 2 from the tailings overflows from Inclined Plate Thickeners . The overflow slurry density is 6-8 %, and 85 % of the particles are of - 37 µ m size , both of which add to the difficulty of mineral separation . There were few successful engineered recovery cases in China before 2020 . BGRIMM employed high shear-force agitation and high-intensity air-forced agitation flotation technology for fine phosphate , achieving a 83 % recovery and a 33 % P 2O 5 grade . For fine ilmenite , BGRIMM has developed a high shearforce stirring and high-intensity self-aspiration stirring flotation technology , realising an excellent metallurgical performance with 46 % TiO 2 grade at 85 % recovery .”
Finally , BGRIMM told IM that it has developed an intelligent optimised control system ( BPM-F ) for flotation processes including flotation froth feature extraction , key indicator prediction , condition recognition and intelligent control . It says existing applications have proven that BPM-F can effectively reduce abnormal operating conditions through flotation control , stabilising the flotation process , and reduce flotation reagent consumption by more than 5 %, as well as reducing fluctuations in concentrate grade by 10 %, while recovery can be increased by 0.5 percentage points . The system has been applied at copper , gold and molybdenum mines around the world such as at the Sanshandao gold mine in Shandong , the Dexing copper mine Concentrator in Jiangxi plus in the DRC at the Musonoie operation of COMMUS SAS .
Woodgrove comes of age
In only 12 years , Woodgrove Technologies has gone from a small start-up player in the flotation market , established in 2009 by Glenn Kosick and Glenn Dobby , both formerly with MinnovEX , to being a core supplier in the industry with a number of significant concentrator installations under its belt – notably in copper such as BHP ’ s Spence Growth Option project SFR flotation plant and Copper Mountain Mining ’ s use of the DFR but also others such as Teck , which is commissioning its Quebrada Blanca 2 ( QB2 ) copper operation in Chile – its flotation line combines FLSmidth 600 m3 nextSTEP cells and Woodgrove SFR cleaners .
Woodgrove ’ s growth is due to the fact that it brought a fresh approach first with its Staged Flotation Reactor ( SFR ) technology , which optimises the three stages of flotation into three separate zones , so that each zone is mutually exclusive of the requirements of other zones . The backdrop of the froth is minimal and tightly controlled . Recovery zone " tight " pulp allows much more control , resulting in better recovery and upgrade . This was followed by its Direct Flotation Reactor ( DFR ) - a flotation cell that works on the principle of preventing the formation of a froth and froth slurry interface . Ultimately its success is based on performing well at real operations .
The main advantages over conventional mechanical cells are reductions to footprint - increasingly a concern for mine operators and reduced energy ; and reduced air consumption . Woodgrove ’ s entrenchment as a major player in the flotation world has also filtered through to SFR and DFR now regularly being named in greenfield mine feasibility studies as preferred technologies or considered for existing concentrator expansions . DFRs are also installed on the same level , so there are no steps between the units - this substantially reduces installation and infrastructure costs .
A greenfield case in point is Generation Mining Ltd which earlier this year announced the results of the feasibility study for the Marathon palladium and copper project located near the town of Marathon in northwestern Ontario . In the first three years of production following commercial production it is set to create C $ 979 million of free cash flow and produce 588,000 oz of palladium and 122 M lbs of copper from approximately 270,000 t of Cu-Pd concentrate shipped . The flotation circuit design incorporates Woodgrove Direct Flotation Reactors ( DFRs ) which it says provide decreased power consumption and improved operational performance .
At Mount Milligan in BC , Centerra expects strong gold and copper production over the 2021- 2023 period . The mill is expected to maintain a stable average daily throughput of approximately 60,000 t / d , the maximum permitted rate . Installation of Woodgrove Staged Flotation Reactors is expected to contribute to achieving targeted gold and copper production levels in 2022 and beyond . A final example is OZ Minerals ’ planned West Musgrave copper-nickel mine in Western Australia which is set to deploy two innovations – Loesche ’ s Vertical Roller Mill ( VRM ) but also Woodgrove DFR for the bulk flotation circuit .
Recently , Woodgrove has provided a number of sites with comprehensive skid mounted units which provide a ' plug and play ' solution . They can include incorporated PLCs , feed tanks and utility manifolds . Installation is simplified with a
38 International Mining | OCTOBER 2021