In the last six months, july to december 2001, the plant has emerged from a twoyear postcommissioning phase to achieve steady state operation. In this regard, a green process for leaching copper from shredded particles of waste pcbs at room temperature was investigated in the present research. It is operated as simple heap leaching process or combination of both heap leaching and in situ leaching process. For more than 30 years, a significant number of processes have been developed to leach copper from chalcopyrite concentrates. Leaching is the process by which constituents of a solid material are released into a contacting water phase. The objective of the research is to recover valuable metal copper by leaching process with solutions of sulfuric acid and. Copper was leached in ammonianitric acid solution at room temperature. Leaching also takes place in nature where the rocks are dissolved by water. Consequently, the metal is separated when the solids are separated from the solution after the leaching process has been completed, and the solution that is produced is termed a pregnant solution or leach. Abstract the alkaline leaching behaviour of rich copper cobalt oxidised ore from katanga has been investigated. Orebodies frequently contain a mix of minerals, commonly varying with depth. Leaching chemistry as outlined earlier, the leaching chemistry that takes place within a total pox autoclave is very complex and will vary from case to case according to the mineralogy of the concentrate fed to the autoclave. Dilute acidic solutions are introduced to the copper bearing ores, causing dissolution of soluble copper minerals table 1 remaining in the leached cap and underlying enrichment blanket. For centuries small amounts of copper have been recovered from acid minedrainage waters.
Hydrometallurgical approach for leaching of metals from copper. Ammonianitric acid leaching of copper cobalt oxidized ore. Flotation of nonsulfide copper minerals is rare because these ores are mostly subjected to hydrometallurgical copper recovery, for example, heap leaching. Post leaching, the rocks areleft with smaller proportion of minerals that they originally contained. Copper sulfide leach solution copper recovery heap leach bacterial leaching these keywords were added by machine and not by the authors. Bioleaching is the extraction of metals from their ores through the use of living organisms. Processes extraction, mining, smelting, refining, leaching.
Technological conditions and kinetics of leaching copper from. Aug 15, 20 this video demonstrates the proposed process for mineral extraction being considered for gogolds parral tailings project in parral, mexico. The copper leaching and copper cementation process the method of dissolution by sulfuric acid and ferric sulfate with chemical precipitation by means of scrap or sponge iron appears to offer the best potential for wide application and low costs. Sunshine mine process plant at kellogg, idaho 1980, but copper concentrate leaching was advanced to larger scales with the commissioning of the bagdad, arizona, concentrate leach plant 2003 and then the morenci, arizona, concentrate leach plant 2006. The effects of time, ammonia concentration, nitric acid ammonia ratio and ph, on the leaching kinetic of copper were investigated. Influence of ferric and ferrous iron on chemical and. This process is experimental and the keywords may be updated as the learning algorithm improves. Leaching of copper ores can be carried out in the following ways. The ore treated in the pueblo viejo gold leaching process contains copper, which is removed from the process as copper sulphide. Leaching is widely used in the biological and food processing industries, such as the separation of sugar from sugar beets with hot water, the extraction of oils from peanuts, soybeans, sunflower seeds, cotton seeds, and halibut livers.
Copper recovery using leachsolvent extractionelectrowinning. For low copper oxide ores the cyclone overflow will be approximately 40% solids and will be directed to a leaching circuit comprising three 300m 3 agitated leach tanks in series. In its pure form or as an alloy, copper cu is one of the most important metals in society. In the north of chile there are many mining industries that produce copper in cathodes from oxidized minerals with the traditional process of leaching, followed by solvent extraction sx, and electrowinning lixsxew. The mount gordon pressure leach process continuous. Heavy medium separation is the process of separating copper ores by a specific medium ferrosilicon density. It utilizes the countercurrent principle, with the ore to be leached remaining stationary, as differentiated from most counter.
Typically these slags are stockpiled and in the case of copper slags can contain up to 1% copper in a form that does not respond well to traditional processing. Consequently, the metal is separated when the solids are separated from the solution after the leaching process has been completed, and the solution that is produced is termed a pregnant solution or leach liquor. Important metals like copper and gold are produced by this process. This work presents a methodology for the design and planning of heap leaching systems to optimize the process. The leaching of dolomitic copper ore the open mineral processing journal, 2010, volume 3 61 sessing the profitability of the process. Improvements in copper heap leaching by use of wetting agents. Copper hydrometallurgy is a branch of metallurgy method to extract copper directly from those difficulttoconcentrate copper oxide ore. This trickles slowly down through the ore, over a period of months, dissolving copper to form a weak solution of copper sulphate.
Copper leaching from chalcopyrite concentrates springerlink. To assist the leaching kinetics oxygen will be injected into each leach tank. The ore will be dosed with sodium cyanide and limeto leach the cyanide soluble gold. Leaching is a chemical process in mining for extracting valuable minerals from the ore. All the results demonstrated that the native communities had the strongest ability of sulfur oxidizing to their local ore samples. The five basic leaching reactor configurations are insitu, heap, vat, tank and autoclave. Covellite, chalcocite and chalcopyrite are generally used as copper ores for bioleaching processes. Glyleach can be used to leach residual metals contained in slags. The process is important because it is the most costeffective method currently in use for extracting both the zinc and lead from concentrates that contain high lead levels 7% or. However, simplified representations of the leaching of chalcopyrite cufes. The transfer of a metal from the ore to the leach solution constitutes a transfer from a solid to a liquid phase.
Finely grained samples of copper i sulphide were leached by h 2 so 4 solution with added nano 3. This process was later on employed for recovering metals from ores containing low quantity of the metal. The third stage is the leaching of copper oxide wrapped. The first process, vat leaching of highgrade copper oxide ore followed by ew of copper from the leach solution, produced low quality copper cathode at relatively high cost. One of the first reports where leaching might have been involved in the mobilization of metals is given by the roman writer gaius plinius secundus 2379 a. Because the dissolution is selective, most of the unwanted components in the ore are unaffected by the leaching process and remain in the solid state. First chalcopyrite copper concentrate leaching using albion. In 1968 there were only two widely practiced copper leaching processes using dilute sulphuric acid. In his work on natural sciences, plinius describes how copper minerals are obtained using a leaching process konig, 1989a, b. During this process, the chemical reaction is the control step, and the reaction order of h2so4 is 0. The actual cost of copper produced by leaching methods is, however, not of so much importance as the fact that ore may be handled in this manner which is not amenable to reduction by any other process. The initial rapid copper leaching rate can be attributed to the high content of unfixed copper ion in the unleached samples. Bioleaching is one of several applications within biohydrometallurgy and several methods are used to recover copper, zinc, lead, arsenic, antimony, nickel, molybdenum, gold, silver, and cobalt. Copper concentrate leaching has been driven by two principal opportunities.
The effects of calcination temperature, solution concentration, solidtoliquid ratio, stirring speed, and reaction. Pdf leaching of copper oxide with different acid solutions. Az of copper ore leaching alta metallurgical services. Leaching of primary copper sulfide ore in chlorideferrous. Oxide minerals also are amenable to ammoniaammonium carbonate leaching reduction. Technically this problem could be solved by neutralizing the acid leach liquor or by leaching oxide copper with ammonia, but neither solution was economical. The fitting results of modified elovich model and doubleconstant model were in good agreement with the leaching process of heavy metals and plant nutrients, indicating their release process in soil under simulated leaching conditions was not a simple firstorder reaction, but a complex heterogeneous diffusion process controlled by multifactor. Extraction of copper by bioleaching is very common since the technique is efficient. Open access the leaching of dolomiticcopper ore using.
Additionally, todays mining equipment makes it possible to reduce waste and decrease chemical exposure during all phases of the copper mining process. Copper was recovered as ametal byprecipitation withhydro. Innovations in copper mineral processing technology. Colemanite is used as a raw material in the production of boric acid. Gold cil carbon in leach process is an efficient design of extracting and recovering gold from its ore by cyaniding and carbon leaching crushed gold ore slurry simultaneously cil process lower the gold mining operation cost and increase gold recovery rate to a degree of 99%. The conversion of copper consists of a series of physical and electrochemical processes. Cesl copper process an economic alternative to smelting glenn barr, jennifer defreyne, keith mayhew cesl engineering abstract cominco engineering services ltd cesl, a subsidiary of teck cominco metals ltd, has developed proprietary hydrometallurgical processes for the treatment of nickel, copper and copper gold concentrates. As the leaching process continued, the content of unfixed copper ions in the samples significantly diminished, giving a smaller driving force by lower concentration gradient pressure for copper ion release. Copper agitated leaching and cementation process of copper problem.
Theoretical foundations and practical considerations eng450 engineering internship a report submitted to the school of engineering and energy, murdoch university in partial fulfilment of the requirements for the degree of bachelor of engineering name. Apart from containing copper, the ores also contain other elements like iron, zinc and sulphur. In order to improve the circular economy of metals, selective leaching of copper from an intermediate raw material originating. The method of recovery of gold from the process slurry is by carbon adsorption. Process improvement and kinetic study on copper leaching from low. In recent years, the expansion of copper bearing waste dump leaching for copper recovery has established a technological basis that is rapidly converting the art of copper leaching into a.
This is much cleaner than the traditional heap leaching using cyanide. In this report, we study chemi cal and physical processes in heap leaching in order to gain a. Leaching of copperi sulphide by sulphuric acid solution. Sulfuric acid is the most common leaching reagent used for the dissolution of oxidized copper ore because copper oxide ore can be dissolved in. Microbial leaching bioleaching, biomining environmental. This process is known as sxew solvent extractionelectrowinning. In 1968 the tonnage of highgrade oxide ores was decreasing and vat leaching was on the decline.
Copper is considered the third most important metal for industry after iron and aluminum, with a yearly production of 10 mt 1. The albion process is an atmospheric leaching process for processing zinc concentrate, refractory copper and refractory gold. A schematic diagram of the conventional process for the production of copper and the sxew process can be seen here. Bioleaching process, also known as microbial leaching or biohydrometallurgy, refers to the solubilisation of metals from insoluble ores by using certain naturally occurring microorganisms 1. The pure metal has a facecentred cubic crystal structure, and. Copper leaching throughout the world copper leaching plants have been widely used for many years. Presently certain metals from sulfide ores and other ores are.
Evaluation of copper leaching in thermally modified. Chapter 6 copper production technology the last boomin technological innovation for the copper industry occurred in the first two decades of this century, whenopen pit mining, flo tation concentration,and the reverberatory smelter were adapted to porphyry copper ores. This application utilizes highquality reactor tec hnology and paques. New copper products copper powder technology ypotential replacement for cathode to rod yspecialty copper powders copper powder process reduces or eliminates the following.
Copper extraction refers to the methods used to obtain copper from its ores. All of the materials used in heap leaching process and industry specifications of materials are. Vat leaching copper ore vat leaching is a simple and efficient mode of effecting adequate contact between the solute and aqueous solvent. First, the ore is treated with dilute sulphuric acid. This paper describes the influence of acid concentration and influence of solidliquid ratio on copper leaching rate from the ore bodies cerovocementacija 2. Liquidsolid leaching preparation of solids for leaching. Methods of metal recovery by microorganisms 2 methods. This process initially involves drilling of holes into the ore deposit. Leaching characteristics of heavy metals and plant. Sherritt gordon minesfound that pressures ofat least 100ibfin2 or 690kpa gauge were necessary for leaching. Mined from open pits, copper ore must be crushed as part of the process that occurs between extraction and production.
The leach rates shown in the simple recovery curves are not all that amenable to analysis in this form. Optimal design and planning of heap leaching process. Flowsheet for ammonia pressure leaching process according to evans eta11 that theammonia willberegenerated using limeand the calcium sulphate willbedisposed of. In recent years, the expansion of copper bearing waste dump leaching for copper recovery has established a technological basis that is rapidly converting the art of copper leaching into a science. Copper processing, the extraction of copper from its ores and the preparation of copper metal or chemical compounds for use in various products. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors. Dilute sulphuric acid ph 2 is percolated down through the pile. The objectives of the study were to evaluate the leaching of low and high dolomitic copper ore using h 2so 4 as the leaching reagent. The first process, vat leaching of highgrade copper oxide ore. Copper ore hydrometallurgy and pressure leachingcopper. Natural bioleaching has been taking place for almost as long as the history of the world, but it is only in the last few decades that we have realized that bioleaching is responsible for acid production in some mining wastes, and that this bacterial activity can be used to liberate some metals. Although the process of heap leaching is an established technology for treating minerals, such as copper, gold, silver, uranium and saltpeter, as well as remediating soil, no studies to date have investigated process optimization.
Separation of special copper ores such as those containing molybdenite or with high zinc or lead content canada is also possible by flotation methods. How hydrometallurgy and the sxew process made copper the. Conventionally, copper is recovered by a pyrometallurgical process known as smelting. It has been postulated that the agitation leaching of copper is a diffusion controlled process. The treatment of copper ores, both oxides and sulfides by means of flotation, hydrometallurgy or other processes has been well established for many years. Addition of both ferrous and ferric iron to the bioleaching medium levelled off the copper extraction and had an inhibitory effect which decreased the final redox potential. First chalcopyrite copper concentrate leaching using. The most obvious leaching differences among the three communities occurred in the leaching process of primary copper sulfide dxore, during which, the ph decreased to 1. In this study, the leaching kinetics of calcined colemanite in ammonium carbonate solutions was investigated in a batch reactor. These processes recover copper via hydrometallurgical leaching of the copper component of chalcopyrite concentrates, followed by solvent extraction and electrowinning.
Copper recovered from leaching low grade copper ores was considered a bonus and little effort had been made to fully understand the leaching process or to maximize copper recovery. Glencore has an operating plant, sable zinc, in zambia that was being unutilised due to the lack of excess oxide copper cobalt ores available in the region and wanted to prove up the concept of sulphide copper leaching at a commercial scale using the albion process tm. Jun 28, 2016 this feature is not available right now. In this process copper ore is mined, crushed, ground, concentrated, smelted and refined. Optimization of parameters affecting recovery of copper from.
Leaching process was first observed in pumps and pipelines installed in mine pits containing acid water. Copper leaching is usually carried out by heap and in situ process details given above. Morenci western copper concentrate mineralogy ymixed chalcopyrite, covellite, chalcocite, pyrite medium temperature and direct electrowinning mtdew process selected ybest fit with morenci concentrate production and acid balance yutilize existing ew and sx capacity at morenci copper production capacity 75,000 tons per year. Although some species may be more of an environmental concern than others, the leaching process is indiscriminant such that all constituents e. The occurrence probability of chemical reactions was analysed based on literature data and products which were formed during the process and the overall leaching reaction was defined.
The mount gordon ferric leach technology is the worlds first integrated pressure leach sxew process to be used to treat copper sulphides on a full plant scale. Adsorption is a term used to describe the attraction of a mineral. To have an idea of bioleaching process copper leaching by bacteria is described as an example. Introduction, methods, application, copper, microorganisms, and processes. The most common types of ore, copper oxide and copper sulfide, undergo two different processes, hydrometallurgy and pyrometallurgy, respectively, due to the different. Explosives or hydraulic fracturing are used to create open pathways within the deposit for solution to penetrate.
Chalcopyrite very slow leaching az of copper ore leaching 5 leachability of copper minerals leachability in sulphuric acid solutions varies enormously see table 1. After the leaching process is complete, the soluble gold must be concentrated and separated from the process slurry. In all ore leaching processes the gangue undesired metals also consume lixiviants along with the metals of interest. Parameters that influence the process, such as ph, extractant concentration, and the aqueousorganic ao ratio were investigated.
A very cheap retrofit was undertaken on the existing oxide leach circuit and then fed a predominantly chalcopyritebornite concentrate 2830% cu. Optimization of parameters affecting recovery of copper. Copper processing is a complicated process that begins with mining of the ore less than 1% copper and ends with sheets of 99. Traditional copper hydrometallurgy process typically consists of atmospheric leaching, solvent extraction sx and electrowinning ew. These interactions can result in degradation of the distributed water. A study of leaching of copper oxide ore by sulphuric. Heap leaching is bat for suitable ores because it allows the economical processing of ore that would otherwise be uneconomic under con ditions that can technically achieve regulatory acceptable levels of environmental risk mitigation.
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