copper ore gold ore extraction equipment with sgs

base metal assays | sgs

base metal assays | sgs

Through our global network of laboratories, SGS experts offer a variety of instrumental and classical techniques to ensure accurate base metal assays. We will help you select a method that is best for your sample type to ensure you get the data you need.

eliminating copper from gold ore

eliminating copper from gold ore

When reviewingMethods of Eliminating Copper from Gold Ores we see that several methods have been suggested to eliminate copper from ores prior to cyanidation. Preliminary extraction of the copper with sulphuric or sulphurous acids may be applicable to ores containing oxidized copper minerals such as malachite, azurite and chrysocolla but these acids have but little effect on sulphide copper minerals, many of which dissolve readily in cyanide solutions. In addition, oxidized ores very often contain appreciable amounts of carbonate minerals such as calcite and dolomite which dissolve rapidly in dilute acids. This leads to excessive consumption of acid.

One method depends upon the property of cuprocyanide of potassium to dissolve copper in certain minerals. This cuprocyanide is obtained by heating the cupriferous ore with cyanide solution. When the cuprocyanide has dissolved its maximum of copper, part of the copper in the solution is precipitated electrolytically during which a partial regeneration of the cyanide is said to take place. The treated ore is then cyanided in the usual way and the gold recovered by electrolytic precipitation. Whether or not any precious metal was dissolved in the preliminary cyanide treatment was not stated.

In another eliminationmethod the copper mineral is dissolved out by means of ammonia after which the ore is cyanided as usual. The copper and ammonia are recovered from the preliminary leach solution by distillation, the copper remaining as an oxide precipitate. The success of this process will depend largely upon the relatively complete solubility in ammonia of those copper minerals which dissolve in cyanide.

The Hunt method-calls for the direct treatment of the ore with a solution of potassium cyanide to which ammonium hydroxide has been added. The gold is thus extracted together with some copper, and the metals are recovered by electrolytic precipitation, the gold, silver and copper falling to the bottom of the vats as a sludge. Zinc precipitation may also be used. The product is low grade.

A old-time metallurgiststated that in treating cupriferous gold and silver ores by the Hunt Process, the strength of ammonia in the solution is varied according to the copper content as well as to the combinations in which the copper is found. It was in use before for treating amalgamation tailings. This material contained a few pounds of copper per ton, present mostly as oxide. In its treatment, it was found necessary to use 8 lb. of caustic ammonia per ton of solution. The strength of the cyanide was 0.05%.

Another example was that of an ore treated inCalifornia, which contained cupriferous,pyrites and silicate of copper. The cyanide consumption was 7 to 8 lbs. per ton which using a0. 15%cyanide solution. When 6 lbs. of ammonium chloride was added to each ton of solution together was sufficient lime to convert all of the ammonium chloride to the hydroxide, the consumption of cyanide was reduced to 1 lb. per ton of ore.

The use of cyanides in the extraction of gold and silver is well known. Such extractions employ concentrations of cyanide in the range of 0.02-0.25% sodium cyanide equivalent in leaching cycles of 24-48 hr and frequently longer. Copper minerals, even though minor components of precious metal ores, dissolve in these cyanide leaching solutions, consume cyanide, cause fouling of mill solutions, and thus interfere with the precipitation and recovery of gold.2,3,4 Here isa summary of laboratory investigations on the use of cyanide solutions as extractants for copper from various copper-bearing ore fractions. In view of the metal contents involved, it will be apparent that larger quantities of cyanide are required to extract copper than for the extraction of precious metals. In cyanide solutions of concentrations generally favorable to copper extraction, sulfide and oxide copper minerals were found to dissolve rapidly at room temperature and atmospheric pressure.

sgs bateman - building on 100 years of experience - international mining

sgs bateman - building on 100 years of experience - international mining

Now celebrating its centenary year, IM Editorial Director Paul Moore spoke to SGS Bateman, the current incarnation of the famous Bateman name in mineral processing technology, which continues to be a leading player in Africa and worldwide in bespoke plants including dense media separation

With multiple mining technology and mineral processing specialist acquisitions in recent years, it is easy to understand why SGS Bateman became famous in the first place, and why it continues to be a global leader in the markets it serves. Bateman, now SGS Bateman (Pty) Ltd, is a great example of longevity in the engineering sector. The companys heritage is based on Bateman Engineering, which was founded in 1921 in South Africa and rapidly expanded globally, specialising in mineral processing plant design and delivery across diamonds, gold and a range of other commodities.

The Bateman family first sold Bateman Engineering to BSGR in 2002. The group was then split into Bateman Projects, based in South Africa, and the Bateman Litwin, which specialised in hydrometallurgical processing. Bateman Litwin, which went on to become Bateman Advanced Technologies is now based in Israel.

The group also included solid-liquid separation company Bateman Delkor in Australia. In 2012, BSGR sold all the assets to Italys Tenova. The EPCM and modular plant part of the company, Bateman Projects, was sold to SGS in 2015; while Bateman Advanced Technologies became Tenova Advanced Technologies (TAT), and Delkor eventually becoming a brand under TAKRAF Group, the mining-focused part of Tenova.

In mining, one of SGS Batemans core strengths has been the design, fabrication and supply of complete mineral processing plants, with a specialisation in dense media separation (DMS) modular plants. To provide a basic description, diamonds are heavier than kimberlite gangue minerals and require specific processing.

Primary kimberlite or marine or alluvial diamond ore, is crushed and screened, then water and dense media (most commonly ferrosilicon) is added with the media forming a very specific pulp density. Hydrocyclones then recover the diamonds as sinks. The process of DMS has been around for well over 100 years. Where SGS Bateman provides value is in delivering the most efficient plant process possible using the right combination of screens, cyclones and media, adapting and customising the process to different types of ores, including diamond bearing ores, and scaling the process to customer needs.

The modular DMS business dates to the 1950s, developed by another South African contracting company, Fraser and Chalmers. Large numbers of plants, processing up to 30 t/h, were sold to the diamond sector and other operations up to the late 1960s when Van Eck and Lurie, another local company, took up the reins. When Bateman acquired Van Eck and Lurie, the DMS business became a strategic business unit, giving it important significance in the company.

There are several advantages to modular designs. Most importantly, modules are fully assembled and tested before they are shipped to the customer, where they are then built on site. Their compact nature also means they can be incorporated easily into larger processing plants. Finally, the modules are standalone, meaning they can be moved to new operations or sold on to new owners. Modularisation has since gone on to be adopted in many other areas of mineral processing but DMS was one of the pioneers, built out of a requirement specifically for remote sites that require top performance.

The ownership transitions from BSGR to Tenova to SGS have not affected Batemans capacity to supply DMS plants traditionally to the diamond industry but also now in new markets including critical materials like lithium. SGS Bateman remains a global leader in DMS for diamond processing and continues to supply solutions to global majors like Alrosa and De Beers (including Debswana and Namdeb) and other companies like Petra Diamonds which acquired several large De Beers mining assets. Other groups such as Lucara in Botswana and MIBA in DRC are also clients. These plants have included everything from small modular plants running 5-10 t/h right up to megamodules handling over 200 t/h.

Most new diamond plants or expansions of existing diamond plants include SGS Bateman DMS technology in some form. Simon Moses, Business Development & Process Manager, told IM: When Bateman first started in DMS modular plants, it was mainly in diamonds and thats where we got our name. It is now a widely used technology in coal as a gravity separator competing with other dense media solutions notably the Larcodems. In recent years what we have found that DMS is being used more in various commodities such as iron ore, base metals like copper, precious metals like platinum, and also industrial metals like lithium.

Iron ore technology development has included ultra-high dense medium separation (UHDMS) technology supplied to Kumba Iron Ore and others. Copper projects have included operations in the DRC treating copper oxide ore. In battery metals and specifically hard rock lithium, Moses says that DMS is now the favoured method for dealing with coarser material, with finer material utilising flotation. The main and evolving producers are trying to avoid flotation where they can to reduce reagent use and lower costs of flotation equipment and power demand that come with fine comminution and running the float plants. Most of them are trying to get to 6% lithium oxide concentrate with recovery of 70%+ with DMS then stockpiling the fines and middlings from DMS for grinding and floating at a later date.

SGS Bateman has supplied DMS plants to lithium projects in Australia. In one example SGS Bateman supplied a 50 t/h modular DMS plant to a lithium producer in 2012 before being selected again in 2019 by the same client to supply a 100 t/h modular DMS plant. The bespoke design beneficiates spodumene ore to produce a lithium concentrate with the plant fully trialled in South Africa before being packed into containers and shipped to site where it is now operating successfully.

Is ore sorting reducing the demand for DMS plants? Moses says that in fact it is just changing how DMS is being applied. Ore sorting is certainly seeing high demand in areas with water shortages. If your process permits you to go dry then sorting plays an important role but generally it will not necessarily permit you to make saleable grades. We see now sorting being used as a preconcentration step in conjunction with DMS to reduce throughput.

In less arid areas, DMS itself is being used as a preconcentrator. We have had clients approach us to preconcentrate using DMS before milling. This is being done a lot in the platinum mines especially for UG2 reef material where you upgrade by getting rid of gangue silicates before milling. By using DMS to preconcentration, the result is a reduction in milling costs. A lot of this activity has been brownfield related where the mine wants to increase capacity underground and increase ROM by placing a DMS between the ROM stockpile and the mill, thus increasing throughput without requiring to upsize the main concentrator plant.

The market still involves a lot of bespoke design, which is where SGS Bateman says it comes into its own. The DMS is dictated by the ore. If it is diamonds, we have standard DMS designs for that for all capacities from 5 t/h up to 150 t/h or more. When you change to base metals, there are a lot of changes as it is very specific to the project and deposit. The design depends on the desired yields, screen sizes etc, different cyclones. Each of the DMS suppliers has its own preferential design in terms of feed and separation method, spillage management, control systems, instrumentation etc but the core DMS process is still the same.

So why has SGS Bateman retained its position in the DMS market? Bateman has been around for 100 years. A lot of clients know the brand from our years of project successes and actually associate the modular DMS plant with the Bateman name.

It is important to reiterate that SGS Bateman does a lot more than just DMS it builds full concentrators, hydrometallurgy plants, and metal refineries for base metals, coal, iron ore, gold, chrome and platinum, amongst others. SGS Bateman also does a lot of EPCM work while supplying modular plant solutions to other EPCM companies where it is appreciated for its specialist experience.

All this said, what synergies are there between Bateman and SGS? Ken Richardson, SGS Bateman Sales Manager: SGS in the early 2010s was growing fast in its core analytics, assay and verification business. In Africa and globally they have a very strong presence operating onsite labs at mines. At the time there were some other smaller companies competing in the metallurgical testwork space who also offered process plant design work and plant upgrades. SGS acquired two of them Time Mining Group in Johannesburg plus KD Engineering/METCON, in 2013. Those two companies became a steppingstone in their decision to buy Bateman and to grow the minerals business into the process plant engineering and design services.

SGS Bateman still operates independently at arms length within SGS as both have their own customer bases and market niches. For example, SGS Bateman sometimes uses SGS labs for ore testwork to back up process guarantees but will also use other labs when appropriate. Having Bateman within the newly created Natural Resources group gives SGS the ability to offer a full suite of services should the customer want to work with SGS beyond initial project scoping studies to full feasibility and project delivery.

gold-copper ores - sciencedirect

gold-copper ores - sciencedirect

The association of gold and copper mineralization in commercially viable ore is a common occurrence. At one end of the spectrum is the predominantly copper ore, which contains levels of gold mineralization. This would be uneconomic to mine for its gold content, but the gold provides a significant opportunity value. This chapter deals with the other end of the spectrum, where copper is present at nuisance levels, which adds to the cost of treating the ore but generally does not provide additional income. The chapter reviews recent and emerging developments in processes targeted at minimizing the cost impact of the copper, which may be manifested in poor gold recovery, high cyanide consumption, high cyanide destruction cost, and high carbon management and/or bullion-refining costs.

Bruno Sceresini has 50-plus years of diversified metallurgical experience in Australia including milling, concentration, nonferrous pyrometallurgy involving smelting and refining, hydrometallurgy involving electrowinning, pressure leaching, hydrogen gas reduction and gold cyanidation including refractory-ore treatment, MerrillCrowe precipitation, CIP and heap leach. He developed and patented the Sceresini process for cyanide and copper recovery from copper/gold ores. He qualified with an MAusIMM and Associateship in Metallurgy, West Australian School of Mines.

Bruno was closely involved in the development and application of enhanced mass transfer and reaction technology, especially in the field of gas dispersion and reaction in slurries and spent almost 10years with worldwide marketing responsibility for the technology in aeration/leaching applications and for contaminated effluent treatment.

He also played a key role in the implementation of a significant R&D program, which funded the design and construction of a 25t/h modular mineral-processing plant utilizing state-of-the-art technology. Bruno is presently involved in metallurgical consulting and in developing a low CAPEX hybrid leach process suitable for treating gold ore occurrences that are too small to warrant high CAPEX traditional gold treatment plants and that are beyond economic trucking distance to a toll treatment plant. The process revolves around fine crushing, gravity recovery of coarse gold and screening of the gravity tail at 0.5mm to produce a coarse fraction for vat or heap leaching and fines for high-shear leaching before recombining with the coarse fraction for extended leaching. Pregnant solution from the vat or heap leach solution is contacted with carbon in an up-flow column. The process can be applied to a wide range of ore types and grades. To date only laboratory scale test work has been carried out. His managerial experience includes various Project Management and General Manager/Managing Director roles.

Paul Breuer has over 20years' experience in gold hydrometallurgy research and process optimization, including cyanidation of coppergold ores and concentrates and the impact of sulfide minerals; cyanide analysis, deportment and speciation; cyanide destruction and recycle processes; and thiosulfate process development as an alternative to cyanidation, including application to gold concentrates and insitu recovery. He has a PhD from Monash University and is a member of AusIMM.

Paul is currently Gold Processing Team Leader and Principal Research Scientist in CSIRO Mineral Resources Flagship. He has been with CSIRO for over 10years, leading research into the extraction of gold and other precious metals from ores. His team provides a range of services to the gold industry including gold deportment investigations (troubleshooting, recovery optimization); cyanide analysis (cyanide speciation, training course); cyanide management (reagent optimization, cyanide destruction/recycle evaluations, site reviews); carbon management (troubleshooting/evaluations, optimization, carbon activity measurement and characterization, course/workshop, operation reviews); development of processes using alternatives to cyanide (particularly thiosulfate); water management (thickener technology, tailing disposal); and process intensification (swirl flow, drag reduction, and oxygen transfer technologies).

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