PRECONCENTRATION

John Chadwick examines Cutting waste the latest in gravity techniques, ore sorting and magnetic separation to raise separation efficiency and reduce concentration costs

“Sensor based automatic ore sorting technology. In bulk tests a very high waste The huge Natalka gold project, owned by Polyus, includes a three-stage gravity circuit; by technologies are used to efficiently remove reject rate of 92.2% was achieved with no gold far the world’s largest – with no less than 52 waste and sub marginal grade material from detected by assay in the waste (98.1% recovery centrifugal gravity concentrators, with sizes up crushed and screened run-of-mine (ROM) ore, assumed based on assay detection limit). As to 42 in. There are multiple concentrators from the two world leaders - FLSmidth’s Knelson producing a coarse (typically 10 mm) upgraded nearly 100% of the gold was recovered, a high > brand and Sepro Mineral Systems’ Falcon preconcentrate at an early stage in the mineral degree of liberation of mineralised quartz reef brand processing circuit. This avoids additional energy from gangue presumably exists at particle sizes intensive downstream processing of this between 25 mm and 60 mm. rejected component of the ROM feed, leading to “The financial modelling confirms robust doubled with ore sorting, from a bulk ROM lower unit operating costs and reduced tailings economics for the project. The base case grade of 0.8 g/t to a mill feed grade of 1.93 g/t disposal volumes.” These are comments from modelling of this potential operation indicates The flow sheet assumes 30% of the crushed and Tony Parry and G van Wyk of Steinert Australia that the grade of plant feed can be more than screened stockpile tonnage prior to sorting is - in their paper Upgrading Low-grade Gold Ore Stockpiles by Preconcentration Using Ore Sorting – an Assessment of the Economic Impact and Viability, presented at the 13th AusIMM Mill Operators’ Conference, October 2016. They reported on test work conducted on bulk low-grade gold ore Bullen stockpile samples from Central Norseman Gold that indicated high gold recoveries as well as high material rejection rates. “A financial model, based on these results, evaluates grade sensitivity and identifies a minimum stockpile grade for adequate financial returns.” The base case modelling estimates that the ex-stockpile grade (including the fines bypassed fraction) can be more than doubled through ore sorting and that the project will be highly viable with strong cash flow generation at stockpile grades as low as 0.7 g/t Au. The modelling enables the company to benchmark ore sorting options against stockpile reclaim and screening operations currently employed. They concluded that the “material is highly Process flow diagram (base case) for gold recovery from Central Norseman Gold’s low-grade gold ore amenable to preconcentration using XRT sorting Bullen stockpile

32 International Mining | MAY 2018 PRECONCENTRATION

25 mm fines which bypasses the sorter. The “Ore sorting technology is plant feed grade uplift, coupled with increasingly being adopted significantly reduced tonnage delivered to the across the gold mining processing plant, results in strong forecast cash industry in Western flow generation for this project and pre-tax Australia, with highly return on capital (IRR) estimated to be 144% encouraging results. over a three year life. The forecast capital Representative samples payback period is approximately six months. collected from the low-grade The financial modelling makes a strong case for stockpile located adjacent to further test work and a potential commercial the portal of the historical operation if stockpile grades of 0.7–0.8 g/t or Rothsay Gold Mine returned higher are confirmed (either through bulk an average stockpile grade mining or selective reclaim of the stockpile).” of 2.5g/t Au. This compares In another Parry-authored paper, with Kai favourably with previous Bartram, Business Development Manager sampling of this stockpile in Mining, Steinert Elektromagnetbau and Luis 2013, which returned results ranging from 2.7 – IMA Engineering Fast Conveyor Analyser (FCA) Loaiza Ampuero of Volcan Compa ia Minera, 4.1g/t Au. More importantly, the results used in sensing coarse primary crushed and/or fine crushed ore before it enters the grinding Upgrading of low grade silver-lead-zincň ore demonstrated that the Steinert Multi-Sensor mills and concentrator. It fast tracks ore grade stockpiles at Volcan Compa ia Minera SAA’s Ore Sorter was able to successfully reject the and type for optimum processing by delivering base metals operations in Peru,ň using sensor- barren ultramafic material located in the immediate feedback based ore sorting, the bulk ore sorting test work hanging wall of Woodley’s Shear.” undertaken on material from low grade Volcan TOMRA introduced its innovative multi- the difficult operating conditions or by ore open pit stockpiles is reviewed. channel laser sorting technology at AIMEX last characteristics. One of the important features of They conclude that “initial ore sorting test August. It said then that this new laser sorting ROM sorting technology is the major material work and subsequent bulk sorting trials have technology “will enable quartz and gold handling infrastructure required. The capital provided data to indicate that the Cerro de processes to achieve higher recovery, better expenditure can be substantial requiring good Pasco low grade stockpile is amenable to quality and more consistent sorting of quartz understanding of the sortability curve (grade- upgrade using XRT ore sorting. Although there material than can be secured using other sensor recovery curve) behaviour of the ore.” are additional significant losses to waste in the technologies. More detail on this was included The paper discusses one industrial case, ore sorting process, the financial analysis in IM’s annual gold recovery article in the where substantial amount of data measured confirms that the major reduction in total feed August 2017 issue. from the ore feed belt has been obtained. This tonnages to the concentrator and the lift in In the diamond sector, a TOMRA X-Ray data was then analysed for the grade recovery metal value per tonne of feed achieved by Transmission machine has been commissioned curves obtainable from that ore with sorting. introducing ore sorting transforms what would at its mine by Australia's Merlin Diamonds. By The XRF measurement used was the FCA be a marginal project into a highly profitable using this technology, it is expected that larger device from IMA Engineering. It is a specially project. The indicated capital payback is diamonds will be recovered than previously built version of XRF designed to operate with approximately six months and the ore sorting possible, as well as recovering low luminescing coarse material. The measurement was taken at project generates a forecast IRR of 207%, while diamonds. It replaces the conventional the main belt conveyor taking ore from the achieving a significant reduction in wet tailings concentrator and detects all diamonds including primary crusher to the stockpile. The crushed tonnages and environmental impact. This coated and low-luminescent as well as ore was about 80% -300 mm at a capacity of suggests that the company’s decision to build and preventing the crushing of larger diamonds. The 1,100-1,200 t/h. Measurement times were varied commission the ore sorting plant is a sound one.” Ector kimberlite pipe will be processed using from 30 seconds to a minute. Measurements There is a lot of this ore sorting test work the TOMRA XRT machine initially due to its high were obtained over several months. going on in Australia. EganStreet Resources proportion of large diamonds. The authors conclude that “the measured announces that it has identified an opportunity At this year’s SME conference, K. Heiskanen grade recovery curves between ore types and to optimise and significantly enhance the et al (colleagues from Outotec and IMA blasted block locations had different signatures. financial outcomes of its 100%-owned Rothsay Engineering) presented Developing real grade- Waste rock could always be detected from both Gold Project, located 300 km north-east of Perth recovery curves for sorting noting that “sorting high- and low-grade ores. High-grade ores in Western Australia, through the application of technology has advanced rapidly recently. Of the benefited from sorting but some disseminated state-of-the-art ore sorting technology. The two possibilities particle sorting has advanced low-grade ores were not amenable for sorting. Company has received highly favourable initial especially in introducing new sensors and the The results clearly point towards the benefits of results from ore sorting testwork completed on use of multiple sensors. The analysing and measuring the coarse mill feed for longer a low-grade stockpile from the historical computing lead times have also shortened. This periods of time at high sampling frequency underground mine at Rothsay, with the key has made it a viable technology option for many before the final technical and economic outcome that the use of a Steinert Multi-Sensor applications but not for the most important assessment of sorting can be made at any mine. Ore Sorter provides an opportunity to increase sorting task at a mine; the ROM ore. Bulk In the studied case there is a possibility to underground mine production (being fed to a sorting, however, has advanced in smaller steps, increase the metal stream to the products up to similar-sized process plant), reduce the impact even if the technology has the capability to 2-3%. It may well be, that the measurement of dilution from the main ore-hosting structure tackle the ROM ore and offers a high potential alone without sorting can give substantial at Rothsay, reduce life-of-mine processing costs to bring mines substantial economic benefits. operational improvements by enabling better and substantially enhance project economics. The sensors, which are useful, are restricted by control and optimisation of the plant.”

34 International Mining | MAY 2018 PRECONCENTRATION

Sorting exploration projects Ore sorting can be very important in determining the economic value of a project. For example, following completion of a large diameter diamond core hole (MSDD261), a further campaign of ore sorting is set to commence to verify the positive results received from initial test work on Middle Island Resources Ltd’s Two Mile Hill tonalite deeps deposit at its 100%- owned Sandstone gold project in Western Australia. n Precursor to first mineral resource for upper half of the exploration target and potential economic upgrade for project n Previous scoping level test work indicated that sorting can deliver a 185%-257% increase in grade, with gold recoveries in excess of 93% and 64% of the sorter feed material being rejected The applied sensors will comprise a combination Ore sorting test work on advanced projects can be The new more definitive, ore sorting campaign of XRT (to detect and separate higher density a very important input to economic and technical n studies, such as is currently happening at Middle will include iterations around crush size and sulphides associated with gold) and laser (to Earth’s Sandstone gold project, some 400km grade range, designed to enhance the original detect and isolate quartz, which hosts the vast northwest of Kalgoorlie results majority of gold). n Validation would likely lead to a significant While the priority remains on establishing the Ambrian Associate Director and acting CEO of positive impact on project economics, sorting characteristics of the primary (fresh) NextOre, Chris Beal, says the industry reaction to delivering reduced haulage and process material, two (or possibly three) weathered/ this ore sorting technique has been very positive. operating costs, and lower tailings disposal oxidised composites of half PQ diamond core will It can pass material through at the rate of 5,000 requirements. also be submitted for sorting at a -45/+15mm t/h, being able to distinguish “the wheat from Middle Island Managing Director, Rick Yeates, crush size, in order to determine the validity of the chaff” in seconds. said: “Ore sorting offers the potential to make a applying ore sorting at the planned Two Mile Hill As a corporate finance company specialising in significant positive impact on the economics of open pit deposit. In this case iterations will focus resources, RFC Ambrian has taken on an unusual the Two Mile Hill tonalite deeps deposit. Should more on material type (oxidation state), rather additional role of working as the commercialiser the new, more definitive, ore sorting campaign than grade range and crush size. and lead marketer of the product in conjunction replicate or improve on the initial trial results, As with the primary (underground) component with Advisian and CSIRO. bulk underground mining at Two Mile Hill of the deposit, a positive ore sorting outcome on Advisian was brought into the partnership becomes a very real opportunity that would the oxide mineralisation has the potential to because of its expertise in engineering solutions substantially extend and enhance the envisaged reduce the unit haulage and process operating including bulk ore handling. The sensing project production schedule. costs, thereby increasing the size of the optimum mechanism has to be paired with conveyor and “While the focus of the current ore sorting pit, resulting in additional potential open pit mill materials handling equipment and suitably campaign is very much on the deeper feed. matched with the size of the operation. underground potential of the Two Mile Hill NextOre, the company being formed by the CSIRO Team Leader, David Miljak, says the ore deposit, given that material is available from three partners, CSIRO and industry players sorter is likely to be most suited to the copper MSDD261 through the oxide profile, we will Advisian and RFC Ambrian, has developed an mining industry as it can detect copper minerals utilise the opportunity to also assess the advanced sensor system that takes advantage of at extremely low grades. He calls high tonnage response of the open-pit mineralisation to ore magnetic resonance technology. It illuminates ore sorting the “holy grail’ of the mining industry. sorting.” batches of ore with short pulses of radio waves, Other ore sorting conveyor machines tend to A series of four primary (fresh) composites assessing ore grade and enabling high tonnage do the sorting on a rock-by-rock basis, with have been selected from HQ and PQ diamond sorting at extremely high speeds. sensors often only penetrating “skin deep” — in core from MSDD261 for crushing prior to ore NextOre’s ore sorter is able to detect the other words, detecting ore particles on the sorting. The composites comprise broad, single, magnetic resonance signatures of many surface of the passing material. By using continuous intervals of half core over three grade minerals, including the most common magnetic resonance radio waves NextOre’s ranges (high grade - HG, medium grade - MG and economically significant iron-and copper-bearing solution not only penetrates all of the ore low grade - LG). The high grade composite, minerals. It also has the ability to detect arsenic- presented on the conveyor, but reads the comprising solely half PQ core, will be separated bearing minerals that are often positively different mineral radio signals, informing sorters into two fractions for crushing to -45mm/+15mm correlated with gold in sulphide ore deposits. It what is present in seconds. and -30mm/+10mm to assess the impact of crush can see through large ore batches in real time as Miljak adds that it is extremely effective at size on sorting, while the MG and LG composites they pass by the sensors contained in an open- detecting levels of arsenic that often occur along are derived from half HQ core and will be crushed ended chamber. with gold orebodies. If the sensors detect at -30mm/+10mm. The magnetic resonance technology (MRT) is abnormally high concentrations of arsenic The composites will be provided to Steinert for often compared with the way MRI technology is minerals, then it can instruct equipment to ore sorting at its commercial-scale unit in Perth. capable of “seeing into” human bodies. RFC selectively reject pods of ore, enhancing a deposit’s

36 International Mining | MAY 2018 PRECONCENTRATION

economic viability. He believes the processing Gekko’s new IPJ3500 is costs for a big mining operation will drop radically 4.5m high, for each pound of copper or ounce of gold 3.5m wide produced — as much as 20% in some mines. and has a feed capacity There is also the positive environmental of 250 t/h aspect of the process. “If we can see what’s in the passing material faster, it means a smaller processing plant that uses less electricity, less water and produces less waste material thrown into tailings and dams. “For every tonne of metal, we offer a much lower environmental footprint. For mines that are constrained by water usage, that’s a bonus,” Miljak says. CSIRO’s Nick Cutmore, who heads up the project’s research team, explains the sensing technology was evaluated at the Newcrest Ridgeway mine in Australia. The testing demonstrated throughput capacity, accuracy and not obvious or for difficult applications and its proven Mag-Screen technology. It will be response times that improve significantly on n Performance testing in full scale sensor-based installed in the existing ball milling circuit. competing sensing technologies. “NextOre’s ore sorting machines The innovative flowsheet is using Gekko’s IPJ sorter should prove useful for both older, mature n Larger scale site-based piloting with a for the pre-concentration of native copper in the mines as well as undeveloped mines. It can extend temporary semi-mobile plant installation. supergene ore that will be an increasing portion the life of older mines and make undeveloped of the incoming ore to the plant in 2018. The IPJs mines viable in the first place,” he says. New IPJ were selected for this application as they can be Before implementation, operations Gekko Systems has been engaged by Canadian fed a relatively coarse particle size distribution, considering sensor-based sorting should mining producer, New Gold Inc, to supply thus allowing the recovery of larger native copper undertake: technology for its New Afton copper-gold mine. flakes. n Geometallurgical evaluation That operation’s new gravity circuit addition will The gravity technology is to be delivered to n Trial tests to investigate sensor response consist of Gekko's largest InLine Pressure Jig site in the summer of 2018 and commissioned n Bench-scale testing where sensor selection is (IPJ) unit - the IPJ3500 – as well as an IPJ2400 early in the fourth quarter of 2018. Knowledge unleashed

United. Inspired.

Certiq Certiq from Epiroc is a telematics solution that gathers, compares and communicates vital machine data. It’s available for all types of mining and construction equipment, both surface and underground. With great knowledge you can create great things. epiroc.com

EPIR-MRE-00002 Internations Mining_Horizontal Ad-Inches.indd 1 4/12/18 11:27 AM PRECONCENTRATION

The SCMG3, Salter Cyclones “We look forward to working with Gekko Ltd’s large scale Multi- Systems on this project to recover native copper Gravity Separator was from our grinding circuit” said Jennifer Katchen, supplied to a client with high tailing Projects Metallurgist, New Afton mine. volumes who Located near Kamloops, British Columbia in wanted to improve Canada, the New Afton mine site includes recovery of fine grained chromite. It underground workings, historic support facilities, was important that a concentrator and tailings facility. The the SCMG3 could underground operation is expected to produce, provide the required recovery on average, 85,000 oz/y of gold and 75 Mlb/y of and upgrading with copper over its 12-year mine life. long-term “Gekko is experiencing a high level of interest durability and low life cycle costs. The and demand in pre-concentration flowsheets equipment is being used as a which support footprint and energy reduction in pilot unit during the initial stage of the process plants. New Gold has recognised the IPJ project capacity to recover native copper in the New Afton flowsheet. We are excited to support this simulates the performance of the Gekko IPJ. The installation.” said Gekko System’s Greg results from the three-stage CGR test can be Rasmussen, VP North America, in early March used to select the size of the IPJ’s and overall December 2017 and in the process met a critical this year. design of the gravity circuit to ensure optimal mine schedule which had high-grade gold ore Following on from the sponsorship of the gold recovery. In addition, these tests will also hitting the plant immediately post AMIRA P420 project in 2001, Gekko has contribute to the AMIRA P420 modelling of commissioning. maintained an ongoing relationship with Curtin gravity recovery from different ore sources. The gravity circuit comprises Gekko Systems University’s Gold Group. December 2017 saw the successful unique dual Mag-Screen technology and an Late in 2017 Gekko’s Metallurgical laboratory commissioning of the turnkey gravity circuit SB2500 concentrator. Mag-Screen in this carried out three-stage Continuous Gravity test installation (gravity box) at the EMR Golden instance was key to the success of the process work (CGR) for Curtin University on two ores; Grove mine in Australia. The circuit was flow sheet given the requirement to maximise Cadia ore from New South Wales and Tropicana designed, installed and successfully gravity concentrate mass yield, remove iron ore from Western Australia. commissioned by the Gekko technical services magnetics from the final Zn concentrate product The 3 Stage CGR test determines the gold team in close collaboration with EMR Golden as well as aid the 70m long pumping duty to recovery from an ore by gravity concentration and Grove teams through late November and early have gravity gold concentrate reporting to the Zn

JUNE 6~8

6th International Congress on  ,  Automation in Mining

Register Today!  

    • The preliminary program of the seminar includes over Manager of Information Senior Process Control 65 presentations by authors from 11 countries among which Technology, Engineer, Teck Highland are Australia, Brazil, Germany, Peru, South Africa and USA. Telecommunications Valley Copper, Canada and Process Control, • In Automining 2018 you will be able to learn about the latest Minera Antamina, Peru innovations and developments in control, automation, and robotic systems applied in mining and metallurgical operations to reduce costs and increase productivity and safety of operations.     Corporate Innovation Manager Site Operations, Manager, Codelco, Chile BHP Minerals Americas gecamin.com/automining

   

DEPARTAMENTO DE IN GE NI ER Í A EL ÉC TR IC A

38 International Mining | MAY 2018 PRECONCENTRATION

concentrate thickener. EMR Golden Grove Processing Manager, John Burgess: “The Gekko team displayed professionalism throughout the process both in the circuit installation and commissioning, demonstrating an ability to work safely and productively. Importantly they were able to deliver on their promises and demonstrated a very strong willingness to work collaboratively with Golden Grove site teams.” Technical performance of the circuit has been pleasing both during and post commissioning with gravity recoveries ranging between 20% and 45% from gold head grades between ~1g/t and ~4g/t. Significantly objectives set prior to project execution were achieved with gold recoveries up by over 11%. Gekko acknowledge the great support received on site throughout the process largest – with no less than 52 centrifugal gravity The layout of the ‘pre-concentrator’ at Spanish by Project Manager Michael Hogan and EMR concentrators, with sizes up to 42 in. The tungsten and tin mine La Parrilla using state-of- the-art processing technology from allmineral to automation, operations and maintenance teams. recovery in stage 1 is around 72%, stage 2, 5% achieve its ambitious extraction targets. As and stage 3, around 1%. The screened gravity noted in the February issue, p4, it has World’s largest separation stage concentrate will gravity flow to successfully completed the execution planning and construction of the plant using two alljig® Proven and Probable Reserves at the huge one of five Gekko InLine Leach Reactors (ILRs), jigs. A fully customised processing plant to be Natalka gold project, owned by Polyus, under the then to CIL, with the second and third gravity commissioned on site by allmineral is soon to JORC code, are estimated at 16 Moz at 1.58 g/t stages direct to CIL. Following CIL are the EW and go online as the last process stage in the tungsten ore enrichment grade. The current >60% recovery is being smelting steps. The three stage gravity circuit achieved even with lower feed grades of 0.6- includes multiple concentrators from the two reagents. 0.8%. By 2019 ore throughput will be 10 Mt. world leaders - FLSmidth’s Knelson brand and The CIL circuit consists of ten agitated tanks What really stands out in the flowsheet is the Sepro Mineral Systems’ Falcon brand. Not having equipped with inter-stage screens and carbon three-stage gravity circuit; by far the world’s flotation means no large volumes of associated advance pumps. The CIL circuit receives reground

LASER MINERAL PROCESSING FOR THE RECOVERY OF HIGH PURITY QUARTZ AND GOLD TOMRA’s new multi-channel laser sorter makes it possible now

For more information, contact us at: [email protected] | Phone: +49 4103 18880 | www.tomra.com/mining

TSMI_International Mining_210x138mm+5_GB_170808.indd 1 8/9/2017 8:40:47 AM PRECONCENTRATION

Based on the outcome of test work, Cradle Arc intends to move forward with a development plan for the upgrades to the Mowana processing plant, including a DMS plant

ILR cake; combined stage 2 and 3 gravity concentrate as well as ILR cake wash solution. The CIL circuit operates at 40 wt% solids with the slurry residence time being 374 hours based on CIL tank sizing. concentration can be deployed at Mowana on a plant. Dense media separation all low oxide ores (those that contain less than “Across the different processes, there are Cradle Arc has received an independent test 25% acid soluble copper) basic principles that are common, such as the report from SGS South Africa detailing analysis The following key metrics were derived by the use of drain and rinse screens to recover sampling results and confirming the applicability company from the independent test work: magnetite from the product and reject streams,” of Dense Media Separation (DMS) for its flagship n A mass yield of 30-40%, and an expected says Kim Schoepflin, CEO of Kwatani. asset, Mowana copper mine in Botswana. copper recovery of in excess of 85% can be She says a concentration of magnetite in the Accordingly, it remains the Board’s intention to expected dilute medium must also be achieved to give a pursue a DMS installation in due course and n Mill feed grades in excess of 2% can be suspension of high relative density, or over further updates will be provided as necessary as expected, nearly double the current ROM dense, medium using wet drum magnetic the development plan for the upgrades to the n An optimal crushing top size of 10-12mm separators. Mowana processing plant progresses. should be designed for with respect to the Schoepflin outlines the fundamentals to be n DMS identified as a low capex expansion upgrade project observed in restricting magnetite losses, option to potentially increase production at n Good rejection of gangue minerals is achieved, regardless of which screening arrangement is Mowana to approximately 22,000 t/y of including carbon and silicon (with more than chosen. copper in concentrate 75% being rejected). “The feed arrangement onto the screen must n DMS could increase throughput to ensure that the full width of the screen is approximately 2.6 Mt/y with reduced cash Dense medium recovery utilised,” she says. “Low feed velocities are also costs, leading to an increased NPV of up to While the evolution of DMS technology has seen critical, as this maximises the drainage rate on $245 million (from the current base case NPV various advances since the mid-1900s, there are sieve bends and multi-slope screens.” of $87 million) still a number of ‘fundamentals’ that will allow She emphasises that the drain section, which n Test work has demonstrated that DMS pre- users to reduce magnetite losses over the life of includes both static and vibrating screens, must

JULY 11~13

5th International Seminar on  ,  Tailings Management

Register Today!  

 -     The preliminary program of the seminar Head of Mineral Academic, AMTC, Residue Facilities, Universidad de Chile includes over 40 articles by authors from Anglo American 14 countries among which are Australia, Brazil, Germany, South Africa, UK and USA. - -      Professor, Norman Geotechnical Professor, B. Keevil Institute, Universidad Técnica University of British Federico Santa María, Columbia, Canada Chile gecamin.com/tailings

    TAILPRO CONSULTING

40 International Mining | MAY 2018 PRECONCENTRATION

have sufficient area to recover 95% of the different densities as a possible pre-stage to the medium being fed to it, and that allowance must wet mechanical separation process. The reason be made for potential blinding which will reduce to develop this kind of equipment is the limited the open area of the screen. availability of water in arid areas or the “It is vital to take the average particle size preference to avoid drying afterwards that and bed depth into account when selecting the requires additions to the wet mechanical screen width,” she argues. “Running at too high processing technologies. Dry gravity separation a bed depth will increase medium carry-over from ensures amongst others an eco-friendly the drain to the rinse section, and will also processing, low energy consumption as well as reduce the efficiency of the rinse water in potential cost reduction due to avoidance of washing off the medium; this in turn will lead to process water circuits and of product and tailings an increase in magnetite losses.” dewatering and drying processes.” Another important aspect to observe is that The functionality of the AKA-FLOW is based on sufficient rinse water must be used to wash off a combination of an air fluidised bed with a the adhering medium, without overloading the special developed sifter. Studies with different wet drum magnetic separators. Provision must raw materials have shown outstanding also be made at the end of the screen – after performance both in terms of throughput, as rinsing – for the clean coal and reject material to well as sorting. “Due to differences in the dewater before being discharged off the end of behaviour of the materials, it is even more the screen, says Schoepflin. difficult to predict the suitability of the dry sorting process (only on the basis of material The AKA-FLOW gravimetric sorting data) compared to wet sorting methods. In the solution The AKA-FLOW can help mines reduce meantime, we reached a level with our own AKA- AKW Equipment + Process Design offers wastewater by reducing the amount of material FLOW laboratory unit, that a statement about to be processed solutions for the wet mechanical processing and the general suitability of a material for environmental technologies. One option for two models, the AF04 capacity 6 t/h and the AF12 reprocessing in the AKA-FLOW is possible, so reducing wastewater in the treatment process is at 9-18 t/h. Both can handle grain sizes from 30 that meaningful results can be achieved even to reduce the amount of material to be m to 2 mm. with smaller sample quantities. Recently processed. In the last ten years AKW Equipment μ “The AKA-FLOW is a dry working gravimetric performed tests show the good results + Process Design has developed and marketing sorting device and used for preliminary especially for recycling material and two-stage the dry gravity separator AKA-FLOW. There are separation and enrichment of materials of purification.” IM

YOUR SPECIALIST FOR MINERALS TREATMENT AND ENVIRONMENTAL TECHNOLOGIES We offer solutions for the wet mechanical and water management processing

AKW EQUIPMENT + PROCESS DESIGN OUR CAPABILITIES

With more than 50 years of experience in minerals treatment and environmental technologies, hundreds RIVXFFHVVIXOO\UHDOL]HGSURMHFWVDQGDWHDPRIH[SHUWVZHDUHWKHSHUIHFWSDUWQHUIRU\RXUVSHFL¿FDSSOLFDWLRQ Technical Laboratory & Trials

&RQVLGHULQJPDWHULDOSURSHUWLHVSURFHVVSDUDPHWHUVDQGGH¿QHGLQSXWDQGRXWSXWTXDQWLWLHVZHHQJLQHHUDQG Engineering realize customized processing plants: technically and economically optimized. Equipment & Process Units GET IN TOUCH Plant Realization Dienhof 26 Phone: +49 (0)9622 7039-0 92242 Hirschau, Germany Telefax: +49 (0)9622 7039-376 www.akwauv.com Spare Parts & Service