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The Daly-Judge Tunnel, begun in 1887 to drain mine workings, is now a source of potable water for the Municipality of Park City. The water is exceptionally clean; however, when roof falls occur, suspended solids levels become too high and water from the tunnel cannot be used in the treatment plant. In 2001, the tunnel was inspected and rehabilitated to ensure that the water supply for the 2002 Winter Olympic Games would be uninterrupted. Twenty-five timber tunnel sets were removed, and 86 steel sets were installed. Timber lagging was installed or replaced over about 230 m (750 ft) of tunnel length.

Jan 1, 2006

By Adrianus (Adrian) Halim, Tomas Bolsöy, Stina Klemo

"This paper describes the ventilation system used in underground hard rock mines in Sweden and Finland, which is very different than the system used in other major mining countries such as Australia, Canada, South Africa, and USA. The system utilizes auxiliary fans with Variable Speed Drive to distribute primary airflow to working levels instead of regulators that are commonly used in other countries. Descriptions about Ventilation on Demand in this system and ventilation regulations in Sweden and Finland are presented in this paper. This paper also quantifies a comparison between the Nordic and the system used in other countries. KEYWORDS Auxiliary fan, Regulation, Ventilation on demand (VOD), Variable speed drive (VSD) INTRODUCTION The primary objective of an underground mine ventilation system is to provide sufficient airflow to dilute atmospheric contaminants that are produced by mining activities. Typically, a mine ventilation system consists of one to four primary fans, regulators to control primary airflow distribution to levels or panels, and auxiliary fans that distribute airflow to dead-end workings via ducts. Depending on circuit geometry, underground booster fans are sometimes used. This system is widely employed in many countries such as Australia, Canada, USA, United Kingdom, and South Africa. However, mines in Nordic countries such as in Sweden and Finland employ a different system, in which auxiliary fans instead of regulators are used to control primary airflow distribution, as well as distributing airflow to dead-end workings. This paper describes the general layout of Nordic ventilation system, its VOD and heating system, its comparison with the system that is widely used in other countries which is referred as “Non-Nordic ventilation system” in this paper, and the current ventilation regulations in Sweden and Finland. The comparison was quantified by doing simulations using Ventsim Design 5 software. DESCRIPTION OF NORDIC VENTILATION SYSTEM General System Layout Figure 1 shows a schematic of typical ventilation system used in Swedish and Finnish mines. The schematic was drawn by Franzen, Myran, Larsson, and Rustan from Stiftelsen bergteknik forskning (Swedish Rock Engineering Research Foundation) and the English translation is written next to the Swedish terminologies. The system is generally a push-pull system. None of Swedish and Finnish mines use exhaust system. As shown in Figure 1, the primary airflow is distributed to levels by auxiliary fans that are bolted to a bulkhead located in the access to intake raise/shaft. These intake fans are attached to ventilation ducts that distribute airflow to all working faces. The exhaust auxiliary fans, which are not attached to any ducts and also are bolted to a bulkhead located in the access to exhaust raise/shaft, then flow the exhaust airflow into the exhaust shaft. A small quantity of this exhaust air is directed into the ramp, which acts as another main exhaust airway. The deepest level is also equipped with booster fan(s) that draw air from the intake shaft/raise and direct it into the ramp to provide fresh air in the ramp. There is no free split in this system. Figure 2 shows a schematic of a level ventilation layout in the Nordic system. Figure 3 shows a photo of these auxiliary fans."

Jan 1, 2019

By J. Tuominen

Outokumpu Direct-to-Blister Flash Smelting is currently in operation in two smelters, a third one is under construction and a fourth one is in the design phase. The two smelters in operation are the Glogow 2 smelter of KGHM Polska Miedz S.A. in Poland and the Olympic Dam smelter of BHP Billiton in Australia. The Outokumpu Direct-to-Blister smelter of Konkola Copper Mines Plc. in Zambia is under construction and the new smelter of Glogow 1 is under design and waiting for final go-ahead decision. Additionally, the Garfield smelter of Kennecott Utah Copper Corp. makes blister copper out of matte in a Flash Converting furnace. A similar operation is under construction for Y anggu Xiangguang Copper Co. in China. The slag cleaning process, which is needed to clean the slag of the Direct-to-Blister Flash Smelting Furnace, has different requirements depending on the feed to the flash furnace. These differences are discussed in the paper. The differences between the processes and slag produced are discussed as well as the metallurgical requirements for slag cleaning. The Direct-to-Blister process, where the blister copper is produced directly from concentrate in one step, requires at least a partial treatment of the slag in an electric slag cleaning furnace. The existing impurities determine the specific requirements of the actual cleaning process. The different processes are discussed in the paper. The newest developments of Outokumpu Technology Oy for electric slag cleaning furnace design are presented as well as the characteristics which the furnace shape gives to the process.

Jan 1, 2007

By J. Aydt, W. McCombe, H. McLaughlin, L. Nightingale-Mercer

The McClean Lake mill is located approximately 850 kilometers north of Saskatoon, Saskatchewan, Canada and is operated by Orano Canada Inc. (Orano). The mill was designed to process high grade uranium ores, and in 2014 completed a multiyear expansion to increase its production capacity to 24 Mlbs U3O8 per annum. This expansion included significant changes to the mill’s secondary leach circuit in support of safely processing high grade ore directly from the Cigar Lake mine. In particular, inter-stage pumps were introduced for slurry transfer between the secondary leach tanks, replacing the original pressure feed forward operation. The design and selection process for these pumps was strongly influenced by the uncertainty related to actual radiation dose exposure when processing undiluted high grade ore (up to 30%U), and consequently the desire to maintain minimal occupancy in the vault enclosure containing the secondary leach tanks. These constraints resulted in the decision to install positive displacement pumps above the leach tanks in a suction-lift configuration. Operating experience with this design has shown that the pump capacity is significantly de-rated due to process solution gas-entrainment and pipe scale build-up, particularly in the front end of the secondary leach circuit where reagent dosage is high. Experience processing high grade ore also provided accurate radiation dose data to demonstrate that the level of occupancy in the leaching vault enclosure could be re-evaluated to accommodate alternate pump configurations. This paper reviews the lessons learned and improvements made to safely increase the capacity and reliability of the leach inter-stage pump system.

Jan 1, 2020

By J. F. K. Brown

WHEN I first received the kind invitation extended to me by the Mining Society of Nova Scotia, I read over very carefully the suggested title-"The importance of long-distance planning and budgetting in modern methods of mining, and the advisability of working to some definite plan". I came to the conclusion that I might as well confess my inability to handle properly such a vast and intricate subject within the scope of any one paper. More properly, I think a round-table discussion should be indulged in-a sort' of symposium carried on in similar fashion to the World Power and Coal Conferences- you know, a committee for this, a committee for that, and, finally, a committee to see what the committees are doing. Weil, your Secretary's suggestion is just like that- much too comprehensive for any half-hour's presentation. As a paper, also, it either becomes too general and therefore uninteresting, or i.t descends into detail and describes means and methods to the end desired, which have little attraction because they were designed to meet quite different conditions than those my audience would mentally be considering. Of the two evils facing me, I have chosen the one that sticks to the generalities. Your Secretary's query almost automatically divides itself into two distinct phases: First, the importance, and second, the advisability, of planning. Let us dwell for the moment on the second, because, if we can prove advisability, that leads to desirability and, finally, to doing. Proving is the difficult part of the little problem. Here was something I, personally and as a mining engineer, had been battling for all my corporate life without being able to prove it to anybody. Then I saw the way out of that. I perceived I could put that little question of advisability on another basis altogether-:put it in the class of "coming- some day- soon" whether you or l or anybody else liked it or not; call it, if you please, mandatory, certain, necessary, enforceable planning. All of which means that the problem of advisability has rather suddenly become the very practical one of "how to do it". Why?

Jan 1, 1937

By G. A. Witwicki

"The Thyssen Mining Group of Companies has successfully applied ground freezing technology to numerous projects throughout Europe and North America for over 100 years. Recently, the aspect of data acquisition and data verification has received greater focus.Thyssen Mining has been engaged in several relatively deep shaft sinking projects over the past five (5) years, all of which have required ground freezing to successfully sink through water bearing rock. To safely and economically sink through a quantity of water similar to Saskatchewan’s Potash Mines, it is imperative to understand freeze wall thickness and growth rate.Critical to understanding freeze wall thickness and growth rate, is the collection of accurate data as well as the interpretation of those data. The data can then be utilized to gain a better understanding of the freeze wall growth rate in active projects as well as to provide data to be utilized in modeling for future projects.This paper elaborates on the installation and operation of the data acquisition system utilized at the Newmont Leeville project, Nevada’s first frozen shaft project. In addition, this paper elaborates on the methodology developed by Thyssen Mining to manipulate the freeze wall data derived through the data acquisition system.The successful incorporation of the new system of collection and analysis of freeze wall data for the Leeville Project has given Thyssen Mining a high degree of confidence in the understanding, as well as prediction, of the ground conditions during shaft sinking.This paper will include:•,A brief description of ground freezing and its objective;•,An overview of previous data acquisition methods employed;•,Current data acquisition methods;•,Installation requirements; and,•,Data manipulation and presentation methods."

Jan 1, 2015

The Cooperative Research Centre for Mining Technology and Equipment (CMTE) is funded by the Commonwealth Government, by its mining research members Ñ the Universities of Queensland and Sydney and the CSIRO1, and by its industry members Ñ BHP Coal, RioTinto R&TD, Hamersley Iron, Mining Technologies Australia, Pasminco, Shell Coal, WMC Resources, Advanced Mining Technologies, and Aberfoyle. The Centre conducts work aimed at improving the competitiveness of the Australian mining industry. The current work is focused in four areas: new mining and drilling systems, geological sensing, automation, and equipment maintenance and reliability. This paper describes much of the work in these program areas that relates to metalliferous mining.

Jan 1, 2001

By S. Shairp

At the Hudbay zinc pressure leach plant, filtration and washing of the second stage leach slurry takes place on a vacuum belt filter prior to disposal to tailings. Due to periods of poor filterability, laboratory studies were undertaken to investigate the effect of temperature of the filter feed slurry, and to compare filterability to the resulting cake particle size distribution.

Jan 1, 2014

By G. S. Hume

THE discovery of natural gas with naphtha in 1924 in the Upper Palaeozoic limestone of Turner Valley, 35 miles southwest of Calgary, has led to continuous developments in this field. Drilling undertaken soon after this discovery demonstrated that the anticlinal structure was in reality a major drag-fold cut off on the east side by a westerly inclined fault of large displacement. The faulted edge of the .limestone at depth determines the eastern limits of the field, which between 1924 and 1936 was shown to have a gas area 14 miles long by about 1 mile wide. Since the strata dip westerly, away from the axis of the fold, drilling becomes progressively deeper to the west and, with the advent of deeper drilling, crude oil was discovered in 1936 on the west flank of the structure but in the same porous reservoir rocks as the gas on the crest and upper parts of the fold. Since 1936, drilling has been undertaken wholly for the production of crude-oil and at present two producing areas have been found within the Turner Valley structure. The larger of these, at the south end of the field, in the vicinity of Highwood river, has a length of about 4 3/4 miles and a proved width of one mile, whereas the smaller, in the north end of the field, south of the north fork of Sheep river, has only a few producing wells.

Jan 1, 1939

By L. M. Lowe, D. B. Chambers, D. G. Feasby

"The presence of the naturally occurring radioactive elements uranium and thorium in rare earth (RE) resources can present challenges in achieving regulatory and social acceptance. The discovery and awareness of radioactivity in mineral resources radioactivity typically generates strong public intuitive responses that may be project prohibitive; a significant proportion of such resources contain radioactivity.The objectives of this paper are to demystify the presence of uranium and thorium in RE resources and to demonstrate how a RE project can be safely developed, operated and closed from a radiological perspective. Radioactivity in RE resources is principally thorium-based. Thorium is interesting and challenging from a metallurgical perspective – one of those stubborn metals commonly assessed as refractory. Thorium is difficult to mobilise into solution and easily precipitates out. Thorium is a common element in the earth’s crust – about 10 ppm on average, and natural geophysical systems conclusively demonstrate its immobility. Specific mine tailings contain elevated levels of thorium, but the contained thorium is neither a significant ecological nor a personal hazard.Waste management for a hard rock rare earth project includes the management of mineral processtailings, waste rock, and metallurgical residue. Proven strategies are available for tailings and waste rockfor all climate conditions. The management of the metallurgical residues is potentially more challenging.Example robust strategies for addressing these challenges are presented.A potential way to reduce the radioactivity of rare earth metallurgical wastes is to selectively remove uranium and thorium. Uranium oxide is readily marketable, but its concentration as a byproduct typically triggers extensive regulatory processes. Thorium is presently not marketable, but may be so in the not-too-distant future with the development of thorium-based nuclear energy. The pro’s and con’s of uranium and thorium byproduct recovery are summarized."

Jan 1, 2016

About Barrick Paste Backfill at Barrick Goldstrike Rodeo Paste Plant Cyclone Lab Testing Challenges and Lessons Learned Future Barrick Projects

May 1, 2013

By W. L. Dam

Grand Junction, Colorado’s legacy with uranium mining and milling serves as a model attracting international interest. Access to water and central location to carnotite ore containing uranium and vanadium resulted in the World War II military creating a site in Grand Junction for developing extraction techniques; subsequently, several commercial mill sites were built in the area. Uranium mills produced ore into the 1970’s as well as tonnes of radioactive waste tailings. Tailings contain radium that emits radon gas. Despite the radiation hazard, sandy tailings were added to concrete and became incorporated into roads, schools, businesses and homes. Clean up of sites containing tailings and mill sites began in the 1970’s involving city, state, and federal officials. The Climax mill site had become an auto junk yard mixed with mill tailings. A new disposal site was built out of town and away from the river in the 1990’s. After Climax mill tailings were removed to the disposal site, the land sat vacant for two decades until citizens and city officials developed a masterplan for the riverfront property. The Las Colonias river park is being built in stages including an amphitheater, gardens, businesses and parks. One of the biggest obstacles to site remediation and reuse was overcoming public outrage, fear, and lack of trust which made funding sources scarce.

Jan 1, 2020

By A. Hashempour, D. Javani

"Selection of an optimal bit is a critical issue in drilling engineering. Specific energy (SE) and Cost per Foot (CPF) are the most common methods for evaluation of bit efficiency and optimal bit selection. The major shortfall of both methods is that they do not directly account for geological and geomechanical parameters of formations being drilling. In this paper, results of using the two foregoing methods are compared using Formation Drillability (FD) method, which directly accounts for geological and geomechanical parameters of a formation. This method combines various geological and geomechanical parameters and yields a dimensionless parameter indicating the formation drilling hardness (drillability). Results of this study show that the amount of energy, cost and time spent for drilling a unit volume / length of an identical formation may vary in different wells. This is due to the fact that geological and geomechanical characteristics of a formation may vary among wells and even within short intervals of a single well. Therefore, an optimal bit may not be appropriately selected, if drilling and economical parameters are the only factors considered and the formation geological and geomechanical specifications are ignored.INTRODUCTIONMany authors such as Bilgesu, Al-Rashidi, Aminian, and Ameri (2000) and Clegg (2006) conducted research in the evaluation of bit performance and optimum bit selection. Almost all of them tried to establish a good relationship based on geomechanical parameters. Primary examples are the research done by Ubaldi (1999), Macini, Magagni, Da Dalt, and Valente (2007)."

Jan 1, 2015

By N. Ginouse, S. Reny

"In the mining industry time is critical as production depends on the speed of the mining cycle. During the mining process, the time required to re-open access for the next phase of an underground heading is a key point that strongly depends on the ability of the selected ground support technique to promptly ensure the safety of workers. Fiber reinforced dry-mix shotcrete has been proven to be an efficient and well adapted technique, able to produce a ground support material with the required energy absorption or flexural toughness in a single application phase. In this context, this paper demonstrates the possibility of significantly speeding up the mining process by using a new fiber reinforced dry-mix shotcrete. The new fiber reinforced dry-mix shotcrete is capable of developing flexural toughness in only 24 hours that is equivalent to what is typically achieved after 28 days using current fiber reinforced drymix shotcrete technology.INTRODUCTIONShotcrete is often used for ground support when using the drill and blast method or other tunnelling methods. But before re-opening access for the next phase of the underground heading, the applied shotcrete is required to reach a minimum compressive strength and in case of fiber reinforced shotcrete, a minimum flexural toughness (energy absorption) in order to ensure the safety of the workers going into the heading. Combined with bolts, the use of conventional fiber reinforced shotcrete becomes an interesting method for ground support as it is applied very soon after excavation and works to stabilize ground movements (Bernard E. S., 2009). In this case, the toughness development of fiber reinforced shotcrete becomes an important feature of the material when looking to speedup the mining cycle. However, early re-entry criteria in underground openings are difficult to ascertain as the load carrying capacity of fiber reinforced shotcrete is usually assessed after 7 or 28 days. For this reason, re-entry criteria varies from one mining area to another and are usually based on compressive strength requirements. For example, in northern Ontario, Canada, one of the current practices in the mining industry consists of allowing safe re-entry once fiber reinforced shotcrete has developed a compressive strength of higher than 4 MPa (Dufour, O’Donnell, & Ballou, 2003). Flexural toughness requirements on fiber reinforced shotcrete are also typically based on evaluation after 28 days."

Jan 1, 2015

By MAX VOS

Lithium is the lightest and electrochemically most reactive of all metals. Renewed interest in lithium coincides with research in lithium batteries and power generation by atomic fusion. Ontario lithium resources are contained in spodumene pegmatites that can form where medium- to high-grade metamorphic volcanic-sedimentary formations are intruded by pegmatite and porphyritic granitic rocks. Spodumene pegmatites occur in at least twelve locales throughout northern Ontario, all of which are in the Superior Province of the Precambrian Shield. Tantalum, cesium, rubidium, beryllium, niobium and tin also were noted with lithium in spodumene pegmatites. Considerable potential remains for discovery of additional lithium and rare-element pegmatites in northern Ontario.

Jan 1, 1984

By J. Desrosiers

"Minnova Inc. has five operating divisions thoughout Canada. One of them is Lac Dufault which was established in 1964.Lac Dufault is located 15 km north of Rouyn-Noranda, in what is known as Noranda volcanic centre, in northwestern Quebec. For more than 25 years, Lac Dufault has produced copper, zinc, gold and silver from four different mines: Norbec, Millenbach, Corbet and now Ansil.Ansil, officially in production since July 1989, is one of the deepest mines presently in production in Quebec. This high-grade copper, gold, zinc and silver orebody is being mined at a rate of 1200 tonnes per day with a total workforce of 200 employees.Of particular interest are the high mechanization level of the underground mine, technical innovations also underground, and computer applications throughout the division.IntroductionMinnova Inc. was formerly known as Corporation Falconbridge Copper until 50% of its shares were bought by Kerr Addison Mines Ltd . in 1986 and it became a member of Noranda Group of Companies.Minnova stands for mining innovation. It means Minnovaaims to use state-of-the-art technologies in mining and exploration to achieve maximum efficiency and cost effectiveness. It also means that they aim to use both proven and innovative management principles to the optimum benefit of their employees and shareholders. Minnova has operations across Canada. Presently four mining divisions produce copper, zinc, gold, silver and lead. Two are situated in Quebec: Lac Dufault (established in 1964) and Lac Shortt (established in 1985); one in Ontario; Winston Lake (established in 1988); and one in British Columbia; Samatosum (established in 1989).Minnova has an annual exploration budget of $15 million divided 60/40 between base metals and precious metals. Most of Minnova's exploration efforts are concentrated around their existing mines. Exploration is carried out from six regional offices located at Rouyn-Noranda and Chapais in Quebec; Thunder Bay in Ontario, Vancouver in British Columbia, Reno, Nevada in the United State and Panama City Panama. Each of the Canadian offices maintains close liaison with nearby operations.Lac Dufault Division is located in the Noranda mining camp, approximately 15 km north of the city of Rouyn-Noranda, in northwestern Quebec (Fig . 1)."

Jan 1, 1991

By K. Kryst, K. Elkayar

The increasing need to process lower grade contaminated copper concentrates and simultaneously produce higher purity copper cathodes necessitates a more diligent control in the electrorefining process. Ion exchange processes can be a powerful tool in controlling electrolyte impurities to ensure trouble free operation within the tankhouse and to help maintain cathode purity. In addition, some impurities can be recovered as a value added product. The use of a short bed ion exchange process provides a unique opportunity for impurity management in copper refineries. Several metals are discussed in this paper, including Sb, Bi, As and Ni and their methods of control and recovery within the copper electrolyte circuit. INTRODUCTION To produce a high purity copper product by electro-refining a copper electrolyte, it is important to control the concentration of impurities such as arsenic (As), bismuth (Bi), antimony (Sb), and nickel (Ni). These impurities are introduced into the electrolyte from the copper anode and can affect the copper product and the production operation. The presence of As in the copper product results in a lower electric conductivity and reduced workability of the copper. High levels of Bi in the electrolyte will result in a copper cathode product containing Bi. High Sb concentration will cause undesired floating slimes. A variety of methods have been developed to control the level of these impurities in the copper electrolyte including precipitation, liquid extraction, and ion exchange. These impurities can be recovered and used. This paper discusses novel methods that utilize short bed ion exchange technology to control these impurities. Also, the use of ion exchange to recover acid from the liberator cells bleed for reuse in the tankhouse is reviewed. SHORT BED ION EXCHANGE Short bed ion exchange technology has been employed extensively in the metal finishing industries for over forty years. Unlike conventional ion exchange, short beds are fixed beds without freeboard space. The application of short bed technology results in significant benefits when compared to conventional ion exchange. The resin used in this technology has a significantly smaller diameter than conventional ion exchange resin. As a result of the smaller resin size, exchange kinetics improves dramatically. This facilitates operation at higher flow rates and the use of smaller beds with a small mass transfer zone length. Smaller beds are especially important for applications that use chelating resins due to the high cost of the resin.

Jan 1, 2019

By Jason Berenyi

Presentation Overview ? What is Potash? ? Where are the potash deposits? ? Current potash mines ? production, capacity and planned upgrades ? Saskatchewan Saskatchewan?s Potash Production Potential s ? Current Status of Potash Exploration ? Increasing Demand for Potash ? Saskatchewan global role

May 1, 2009

By Jianwen Yang, Yucai Zhou, Yanhong Dong, Daixiong Chen

"The study of combined depressants for flotation separation of lead from copper has been carried out to solve the copper-lead separation problem. Test results show that the depressant of CMC (Carboxyl Methyl Cellulose) or sodium sulfite plays an important role on the selective depression of galena flotation. When the two reagents above are combined, the selective depression effect on galena is further enhanced. When the mass ratio of CMC to sodium sulfite is 1:4, galena was best depressed, with the lowest lead content in the copper concentrateClosed-circuit tests indicate that under a certain pH value of the slurry, with the best ratio of CMC to sodium sulfite as depressants, the copper concentrate with the grade of 28.23% copper and 4.12% lead is obtained, and the copper recovery is 84.87%; the lead concentrate with 68.12% lead and 0.86% copper is obtained, and the lead recovery reaches to 92.20%. An efficient separation of copper and lead is achieved with the combined depressants. INTRODUCTIONComplex copper-lead-zinc sulfide ore is abundant in China. With the rapid increase of mineral consumption, it has become one of the important sources to produce copper-lead-zinc metals. However, it is difficult to achieve effective separation of copper and lead, due to the complicated ore properties, such as fine dissemination, low copper grade, complex symbiotic relationship and similar floatability of copper and lead.Poisonous reagents of bichromate and cyanide are often used as depressants for copper lead separation. They have good separation efficiency, but pose serious pollution issues. As the environmental protection is becoming more and more important, it is a trend to replace traditional toxic reagents with new nontoxic efficient chemicals. Organic depressant FCLS studied by Liu has strong selectivity against galena, and does not depress chalcopyrite. A new type of galena depressant of CLS-01 discovered by Jin-lin Yang shows good results in the separation a mixed copper and lead concentrate. In addition, dextrin, chitosan and some other natural organic compounds (Drzymala, 2003; Huang, 2012; Qin, 2013) have also been studied to separate copper and lead."

Jan 1, 2016

By D. B. Dreisinger, A. A. Gunaratnam

A pressure oxidation (POX)-hot cure (HC)-lime boil (LB) process is used in industry to recover silver from refractory gold sulfide ores containing minerals such as pyrite and arsenopyrite. Pressure oxidation is used to oxidize minerals and liberate occluded gold particles. As such, iron goes into solution and under acidic and high temperature conditions often precipitates as basic iron sulfate (BFS). BFS consumes excess lime during neutralization prior to cyanidation. Therefore, a hot cure stage is required to re-dissolve BFS back into solution. BFS re-dissolution consumes acid and produces ferric sulfate. In the presence of silver, these conditions favor the slow formation of silver jarosite. Silver jarosite is refractory to cyanidation, and must be broken down prior to cyanidation. This is done in the lime boil to produce a cyanide-soluble silver hydroxide. A study was conducted to investigate parameters that affect the precipitates that form in each stage of the POX-HC-LB process.

Jan 1, 2017