Search Documents

By R. Rodgers

The Pinto Valley Concentrator of BHP Copper Inc. restarted its sulphide mining operations in September 2007 to produce copper and moly concentrates. During the plant production ramp up, the copper/moly circuit quickly reached the copper grade and recovery targets, but the production and quality of the moly concentrate continued to be a challenge. Even though several improvements in the moly circuit were completed, the final moly concentrate did not meet contractual specifications. After reviewing several options to improve grade and reduce contaminants, the installation of three flotation columns was chosen. The column design and construction were done utilizing in-house craftsmen and engineers. Ten days after commissioning, the columns successfully reached a steady operation and began producing moly concentrate to the required specifications, that is, high moly tenors and low copper and iron content. In this paper, the operating parameters, mass balance, design, installation, commissioning and operation of the new flotation columns will be discussed.

Jan 1, 2010

By Douglas R. Hardin, Stanley L. Worst, Joanna Mason

A challenging earth retention project presented itself in Washington, DC in the backyard of the historic House of the Temple (The Scottish Rite of Freemasonry, Supreme Council 33°). Located at 15th St NW and S St NW, a forty-foot-deep underground basement was to be installed adjacent to the existing Temple, a historic Carriage House structure dating back to the 1800’s and across a narrow alley from a four-story brick apartment building. The unique geology of the site included typical urban fill overlying a mixture of loose alluvial soils underlaid by dense marine deposits of the Potomac Formation. The clay, sand and gravel of the Potomac included nested boulders up to three feet in diameter. Design of the earth retention system accounted for ground conditions, installation methods and estimated movement of the system and adjacent structures. Anticipated ground water and unanticipated water from leaky sewers also proved obstacles to overcome during construction. Soldier beams were installed using a variable momentvibratory hammer to minimize disturbance to the historic and sensitive structures. Monitoring of the existing structures included both seismograph and optical targets during installation of soldier beams and as the excavation progressed. Micropiles drilled into the Potomac Formation were a part of the permanent foundation for the new structure. This local case history will delve into the details of the successful design, installation, and performance of an earth retention system and micropiles in a historic and highly congested urban environment.

Oct 1, 2022

By A Weber, L MacNamara, H Schreiber

Design and development of the world?s largest flotation cell was completed in 2002. This was the first 257 m3 flotation cell installed in the mineral industry and represents a major development in the design of larger flotation cells. This cell has a 50% increase in volume over the widely installed 160 m3 WEMCO® Smartcell? flotation machine. In the next few years it is anticipated that 257 m3 flotation cells will be incorporated into rougher-scavenger flotation circuits in many more world class copper sulphide concentrators. The prototype 257 m3 cell, No.250 Smartcell? flotation machine was installed at Minera Los Pelambres in the front of Row 1 in the existing rougher flotation circuit. This cell is followed by nine No. 130 Smartcell? flotation cells. After the successful development phase, this unit has been incorporated as part of a row of No. 250 Smartcell? flotation machines at Minera Los Pelambres. A key to the successful development of the equipment has been the emphasis placed on fundamental hydrodynamic scale-up criteria. Hydrodynamic factors include superficial gas velocity, water (pulp) circulation through the draft tube, and pulp mixing (distribution) characteristics. This paper will review the scale-up criteria of the No. 250 flotation cell, and present a case study of the in-plant equipment testing. The case study will document the metallurgical and hydrodynamic performance of the machine. It will also illustrate the economic benefits derived by incorporating larger flotation cells in a modern copper sulphide concentrator.

Jan 1, 2007

By Marco D. Boscardin, Kenneth A. Pidgeon, Adriane G. Boscardin

"Hollow bar tiebacks can offer an economical alternative to conventional solid bar and strand tieback systems for use in temporary excavation support construction. However, the limitations associated with the installation of hollow bar tiebacks require special attention during design, construction and load testing to verify conformance with conventional performance and proof testing criteria (PTI, 2014). In particular, providing a reliable free length is complicated by the 10-foot (3-m) -long, segmental, couplingto- coupling nature of the free length sheath in the hollow bar system, and addressing the fully grouted annulus of the bond zone and the free length zone at the end of installation are key concerns. In addition, it is often more convenient to install a greater number of more closely spaced, lower capacity tiebacks with the hollow bar system, compared to conventional tiebacks. This paper examines how these issues were addressed for a project involving a 60-foot (18-m) -deep sheet pile excavation through a highway embankment and a 70-foot-deep sheet pile and soldier pile and lagging excavation through a railroad embankment, both supported by a hybrid system of hollow bar tiebacks and hollow bar soil nails. The project involved approximately 300 tiebacks and 400 soil nails.INTRODUCTIONEngineers Construction, Inc. (ECI), constructed a pair of 32-foot (9.8-m) -wide (clear span), 30-foot (9- m) -high (21 feet (6.4 m) above the stream bed), cast-in-place concrete arch culverts as a design-build project for the Vermont Agency of Transportation (VTrans) in East Ryegate, Vermont. The new culverts replaced an existing 8-foot (2.4-m) -wide by 6-foot (1.8-m) -high cast-in-place concrete culvert under US Route 5 (RTE5), and twin, 2-foot (0.6-m) -wide by 5-foot (1.5-m) -high granite block culverts under the Washington County Railroad (WACR) alignment. The culverts convey Manchester Brook eastward, through the embankments for RTE5 and the WACR, on its way to the Connecticut River. The Connecticut River is located approximately 100 feet (30 m) east of the WACR embankment. The existing structures were undersized and backed up water behind the embankments during high flow events; and often trapped debris that flowed down the brook and became clogged. The existing culverts also had cracks and openings that have resulted in the loss of ground into the culverts and the formation of sinkholes in the sides of the embankments. Moreover, the reason for the large cross-sectional dimensions of the culverts was to make them of sufficient size and openness to encourage the migration of fish up the stream to spawn. The culvert through the RTE5 embankment is 144 feet (44 m) long, and the culvert through the WACR embankment is 128 feet (39 m) long, with a 57-foot (17.4-m) -long by 32–foot (9.8- m) -wide by 17-foot (5.2-m) -deep 10 feet (3 m) deep above the stream bed) open channel section between the two culverts. A plan view of the culvert alignment is presented in Figure 1."

Jan 1, 2016

By B Nielsen, H Lehto, B Musuku

"The demand for fine and ultra-fine grinding associated with the processing of more challenging, finer grained orebodies and the global driver of minimising energy consumption has been an increased focus in our industry. Outotec’s stirred milling technology, the high intensity grinding mill (HIGmill™), was launched in 2012 in response to this industry need. First Quantum Minerals Ltd selected HIGmill™ technology for its Kevitsa mine in Northern Finland. The 700 kW mill is grinding copper rougher concentrate to improve copper/nickel separation and copper recovery. Selection of the HIGmill™ followed mineralogy analysis and laboratory and pilot testing for HIG milling in parallel with flotation tests to determine optimum grind size and energy input.The paper discusses the challenges and successes of the test work, manufacture, installation, commissioning and subsequent operation of the mill. Grinding performance is presented and a comparison between predicted and operating energy efficiency is made. In addition, the various steps to optimise wear rate and minimise maintenance and downtime are made, with particular reference to internal geometry of the mill.Citation:Nielsen, B, Lehto, H and Musuku, B, 2016. Design, Installation, Commissioning and Operation of Fine Grinding Technology at the Kevitsa Mine, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 59–66 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Fallins J

THE John Darling Colliery, owned by The Broken Hill Proprietary Company Limited, is situated 12 miles south of Neweastle, NSW and about 1 mile from the ocean. The area of the holding is approximately 10,000 acres, about half of which underlies the Pacific Ocean. The area was proved to be coal bearing by diamond drill boring: this method not only proved the coal to exist, but gave the depths from which could be calculated. It also proved the existence or otherwise of heavy faulting, which is a very important factor in the design of the underground lay-out of a mine. The location of shafts had to be carefuIly studied, and, before final selection, the following salient points had to be considered:Railway communications.Flood waters.Boiler feed water.Surface buildings.Probability of coal washing.Underground haulage arrangements.Lengths of roadways from a ventilating viewpoint.Before the shaft sites were finally selected, an underground design was prepared to determine the direction of the main drives in relation to the boundaries of the holding, and the of the coal seam: the latter, being an important factor in this particular locality, was ascertained by a geological survey of rock outcrops in the neighbourhood. Size of shafts was the next subject for consideration. This was determined by output, number of seams to be worked, amount of ventilation required, and, on...

Jan 1, 1930

By Remmerswaal, U. Boin, M. B. G. Castro

"To design sustainable products that can be recycled with high resource efficiency, low environmental impact and economic feasibility, the choice of materials and materials combinations, made in the design stage, is fundamental. The products we design, manufacture and use now will be the resources of the future. Designers are able to select materials for a product according to the many functional requirements they must fulfil. But they have a limited knowledge of the recycling processes and its requirements regarding quality of the secondary material streams. Resource Engineers have to manage the processing of these streams, that are becoming more complex with the increasing variety of materials and decreasing size of components. After mechanical separation of the materials streams resulting from shredding of EOL (endof- life) products, there is always a degree of contamination, from two possible causes:Incomplete liberation: the bonds between different materials combined in a component are not completely destroyed by shredding, resulting in some particles containing two or more materials attached;Separation efficiency: the mechanical separation processes are not able to separate perfectly the many material particles; there are always a number of foreign particles in the recovered streams.Sometimes, those contaminants cannot be removed by the industrial metallurgic recycling processes, and a more serious problem occurs when the contamination levels compromise the recycling of the material stream by lowering its quality (i.e. the properties of the recycled material will be lower due to the contamination). As a consequence, the material must be diluted in virgin raw material and/or used in a less demanding application (downgrading), causing resource depletion and increased energy use, waste production and recycling costs. In order to make the best choice of materials combinations for a product, a systematic approach is necessary, that can close the gap between the knowledge areas of Product Design and Recycling Technology."

Jan 1, 2003

By Stephen Buttling

The construction of a water treatment plant in Dandenong, Victoria, required detention tanks and a pumping well. The design provided by the Engineer used conventional rectangular cast-in-situ reinforced concrete walls within a sheet piled cofferdam. It was decided to construct the tank and shaft using the diaphragm walling technique as an alternative and, for the shaft in particular, this involved a “circular wall”. Except where cutters are used, joints in diaphragm walls have to be made between colinear panels, with waterproofing provided by dumb-bell water stops held within trapezoidal forms. This means that the circle has to be approximated by a number of straight sides, which in this case was twelve. The requirement was to design the reinforcement for the strange shaped panels. Finite element analysis was used, in the first stage using an axisymmetric model to determine the profile of lateral earth pressures with depth. In the second stage a horizontal slice was modelled, without gravity which normally operates from the top to the bottom of the page. By considering appropriate possible earth pressures at different depths, a range of bending moments was calculated, which was used by the structural engineers to design the rebar. The tanks were successfully constructed, and inclinometers were installed in both the tank and the shaft. Measured deflection profiles show that the design was moderately conservative.

Nov 1, 2022

By Juan B. Yianatos

"After almost 100 years, since the first commercial application began in Australia, flotation has shown an extraordinary growth and nearly 2 billion tons of ore per year are presently treated by flotation processes. During this time flotation has promoted a wide scope of research activities ranging from fundamental chemistry and hydrodynamic studies to studies of industrial operations. In general, fundamental studies have been mainly related to ideal situations. In recent years, however, large efforts have been focusing on achieving a better insight into the actual sub-processes provided by the development of new and more sophisticated instrumentation. Since the massive incorporation of flotation columns, around 15 years ago, a renewed interest in flotation fundamental studies, process modelling and new cell designs have been observed worldwide. The key role of the froth has been recognized as an independent and sometimes rate limiting process step. Thus, separation of pulp and froth process stages seems the most appropriate in terms of process modelling, diagnostic, design and scale-up purposes.In relation to flotation equipment development, until the middle of the 1970’s, only the sub-aeration mechanical cells were dominant. Since the 1980’s, the use of pneumatic cells and forced air mechanical cells has emerged strongly. Also, in the last decade, flotation equipment has shown a dramatic increase in size, reaching values of 200m3 in unitary mechanical cells and more than 300m3 in columns. The general feeling, however, is that, despite the great advance observed in terms of process knowledge, the mechanisms and principles of industrial flotation cells design and scale-up are still not fully understood.Advances in process instrumentation and control now in use allow for more efficient operations, both in metallurgical performance and savings in operating costs."

Jan 1, 2003

By Juan B. Yianatos

"After almost 100 years, since the first commercial application began in Australia, flotation has shown an extraordinary growth and nearly 2 billion tons of ore per year are presently treated by flotation processes. During this time flotation has promoted a wide scope of research activities ranging from fundamental chemistry and hydrodynamic studies to studies of industrial operations. In general, fundamental studies have been mainly related to ideal situations. In recent years, however, large efforts have been focusing on achieving a better insight into the actual sub-processes provided by the development of new and more sophisticated instrumentation. Since the massive incorporation of flotation columns, around 15 years ago, a renewed interest in flotation fundamental studies, process modelling and new cell designs have been observed worldwide. The key role of the froth has been recognized as an independent and sometimes rate limiting process step. Thus, separation of pulp and froth process stages seems the most appropriate in terms of process modelling, diagnostic, design and scale-up purposes.In relation to flotation equipment development, until the middle of the 1970?s, only the sub-aeration mechanical cells were dominant. Since the 1980?s, the use of pneumatic cells and forced air mechanical cells has emerged strongly. Also, in the last decade, flotation equipment has shown a dramatic increase in size, reaching values of 200m3 in unitary mechanical cells and more than 300m3 in columns. The general feeling, however, is that, despite the great advance observed in terms of process knowledge, the mechanisms and principles of industrial flotation cells design and scale-up are still not fully understood.Advances in process instrumentation and control now in use allow for more efficient operations, both in metallurgical performance and savings in operating costs.INTRODUCTIONFlotation is a widely used process within the minerals processing industry, as well as being used for water treatment and de-inking of recycled paper. Froth flotation started in Australia at the beginning of the 20th century and since then flotation technology has made significant advances. Flotation was firstly applied to sulfide ores. The largest tonnages treated by flotation are copper and copper/molybdenum ores, handling about 50% of the total ore processed. Also significant are phosphate, iron ore and coal treatments. At present, Chile is the foremost copper producer in the world with around 35% of the world?s production. Figure 1(a) shows the evolution of copper production in Chile over the last decade. The total amount of fine copper produced in year 2001 was 4.7 million tons, from which 3.2 million tons was processed by flotation while 1.5 million tons went through LIX-SX-EW processes, which also showed significant development during the same period (Anon, 2001). The total flotation treatment of copper ores in Chile is about 325 million tons per year (Anon, 2002), so the world treatment of copper ore by flotation can be estimated at about 1 billion tons per year. Consequently a total of nearly 2 billion tons of ore per year is presently processed worldwide by flotation (Fuerstenau, 2001). In order to handle the higher tonnage of low-grade ore, a worldwide trend towards the development and use of larger flotation machines began in the 1960?s. Figure 1(b) shows that the trend became extremely marked from the beginning of the 1990?s, which is consistent with the strong increase in copper production during the same period."

Jan 1, 2003

By Tom Wynne

In order to shorten the time required and improve safety for a longwall face move, a 36-ft wide longwall recovery room was predriven. The room was supported with specialty bolts, trusses and concrete cribs. Rock mechanics instrumentation was implemented to evaluate the adequacy of the whole recovery system. This included instrumented roof bolts, entry convergence, load cells, and abutment stress in the surrounding pillars. This paper describes the methodology of support and instrumentation designs, and monitoring and evaluations. The results indicated that this method offers the safest and yet faster longwall recovery so far. But the rock mechanics monitoring also indicated some improvements are desirable in the truss system and concrete crib layout.

Jan 1, 1993

By J.N. Kohmuench

Teeter-bed (i.e., hindered-bed) separators are used throughout the mineral processing industry for both classification and density separation. The high capacity and sizing characteristics of these units make them ideal for feed preparation prior to coarse flotation (+0.100 mm) circuits. Teeter-bed separators are typically easy to control with two basic operating parameters, including fluidization water rate and bed level. However, data show that these two parameters greatly interact with one another. Given this finding, a high-level automatic control scheme was developed and implemented on a full-scale separator. In addition, dialogue with plant operators has led to several simple changes to an already established design that improves operational and maintenance characteristics.

Jan 1, 2010

Teeter-bed (i.e., hindered-bed) separators are used throughout the mineral processing industry for both classification and density separation. The high capacity and sizing characteristics of these units make them ideal for feed preparation prior to coarse flotation (+0.100 mm) circuits. Teeter-bed separators are typically easy to control with two basic operating parameters including fluidization water rate and bed level. However, data show that these two parameters greatly interact with one another. Given this finding, a high-level automatic control scheme was developed and implemented on a full-scale separator. In addition, dialogue with plant operators has led to several simple changes to an already established design that improves operational and maintenance characteristics.

Jan 1, 2010

By C. Stollberg

The recovery of valuable materials from electronic waste is of growing importance for the re-source management not only in the industrialized nations. Being a significant step in an innovative automated process for recycling of metals and plastics from used electric and electronic equipment, the results of the work introduced below, prove the applicability of microbial leaching of metals from printed circuit boards (PCBs) at industrial scale. Within the first project step, which started in March 2005, experiments in shaking flasks with a mixed culture of chemolitotrophic bacteria (mainly Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans) were carried out to study the solubilization of non-ferrous metals present in the electronic waste. It was found that the best results were achieved by means of a two-stage process in which leaching of these metals was carried out by acidified ferric sulphate solutions generated as a result of the prior bacterial oxidation of ferrous ions to the ferric state. Special reactor systems for bacterial generation of such solutions and for the subsequent leaching of non-ferrous metals from the waste were developed, constructed and tested under laboratory and pilot scale conditions. The optimum technological parameters such as concentration of iron ions, pH-value, temperature and presence of nutrients were established for both reactor systems. Parameters such as particle size, pulp density and flow rate of the suspensions being leached were established for the leaching process carried out under continuous-flow conditions. The complex flow sheet reflects a highly efficient technology on the basis of metal recovery, environmental effect and economical acceptance. The process was successfully implemented into an industrial demonstration unit.

Jan 1, 2014

By Frank Borda

Two recent projects were completed in Ontario, Canada for major hospital additions that involved excavation support of heritage masonry structures. Conventional continuous caisson wall schemes were replaced, with significant cost savings, by tied back shotcrete systems. Using a combination of conventional design and FLAC analysis, excavation support was designed to permit excavation in competent to weak soils that limited horizontal movements of the existing structures to between 3 and 8 mm. The use of vertical wall elements (micropiles) integral to the shotcrete wall to support both the vertical wall loads and the face of the excavation was deemed to significantly reduce lateral and vertical wall movements. FLAC analysis was used successfully to predict wall movements and optimize design. The shotcrete method proved to be flexible and adaptable to design changes during the project. This permitted convenient accommodation of changes to the building geometry after excavation support had commenced. In addition the method accommodated staged demolition and excavation support of portions of the existing structure at low cost, conveniently and without delays.

Jan 1, 2004

By J. B. Rubinstein

"The paper gives an overview of the history of flotation machine development. The laws of their evolution are stated and the place and role of column flotation are demonstrated.The major parameters of column cell diameter and height are discussed. Options are proposed for optimization of the hydrodynamic characteristics of large-capacity column cells. The high efficiency of columns with cell height of 4-6 m is demonstrated. The optimum parameters of multisectional column machines are determined. Their advantages compared to monocells are shown. A scaling-up procedure for column machines was developed based on flotation macro- and microhydrodynamics simulation."

Jan 1, 2003

By J. B. Rubinstein

"The paper gives an overview of the history of flotation machine development. The laws of their evolution are stated and the place and role of column flotation are demonstrated.The major parameters of column cell diameter and height are discussed. Options are proposed for optimization of the hydrodynamic characteristics of large-capacity column cells. The high efficiency of columns with cell height of 4-6 m is demonstrated. The optimum parameters of multisectional column machines are determined. Their advantages compared to monocells are shown. A scaling-up procedure for column machines was developed based on flotation macro- and microhydrodynamics simulation."

Jan 1, 2003

By Gerasimenko MP

The authors consider the features and advantages of a new promising trend in mineral processing - column flotation. Design aerohydrodynamic and process characteristics of pilot-scale columns are studied. Optimum process parameters for various ores and operations are studied. Flow patterns in cells of various cross-sections are investigated and the relationship between Peclet criterion and specific capacity of cell is determined. On this basis options were developed for optimisation of hydrodynamic characteristics of large capacity cells, including longitudinal sectionalising of the collection zone. It is shown that advantages of high column cells (10 - 13 m) produced in the West can be implemented in a sectionalised machine of smaller height (5 - 6 m). Investigations on the influence of slurry and air bubbles flow patterns indicated that to increase flotation rate of particles of various flotabilities it is expedient to combine co- and counter-current flows of phases in a single column. The proposed designs allow tailings to repeatedly return tailings to the collection zone and alternate co- and counter-current slurry and air flows. For the first time columns with alternating slurry flows (combination of co- and counter-current flows) are developed and commercialised. Unique multi-sectional cells having a number of essential advantages compared to monocells are developed. Design features of the cell allow: implementation of different flotation process flowsheets in a single unit, improved beneficiation process results, reduced specific power requirement, and elimination of sludging of the aerator and cell bottom part. Operational problems restricting introduction of column cells are connected with the aeration unit. The new cells are supplied with pneumohydraulic and stepped airlift spargers, allowing control of bubble size distribution with a service life of not less than three years. Successful operation of the new generation of columns with cell volumes of 15, 25, 40, and 80 cu m and the height of 5 - 6 m in copper, molybdenum, antimony, tungsten and nickel ores and coal slurry processing at different plants in this country illustrated their considerable process and operational advantages and verified the proposed options and relationships. A simulation technique of the flotation process and models for the solution of various problems are developed. A modular model of column flotation is constructed taking into account the kinetic relationship of the process and the hydrodynamic regime in the cell. Based on this, a technique of calculating the column parameters based on laboratory tests is developed (scaling-up), and applied for calculating the design of commercial-scale columns is developed.

Jan 1, 1993

By John S. Pack

The application of square shaft helical piers in expansive soils is a standard of practice in many areas of the United States. Over 20 years of performance monitoring show exceptional performance and economy will result if proper design procedures, specification requirements and installation procedures are followed. This is true for new foundations and the repair of existing foundations, including lightly loaded wood-frame structures on expansive soils. Proper design includes: 1) site geotechnical characterization, 2) pier layout such that each pier is loaded to its maximum design capacity, 3) maximize spans between piers, 4) minimize the number of piers, 5) isolate the structure from the expansive soil with an appropriate void zone below all grade beams, slabs or other components that would otherwise be in soil contact and 6) utilize only single helix piers. Proper specification employs a performance specification that specifies: 1) the design load on each pier with a suitable safety factor, 2) the minimum installation torque, typically 4,000 ft-lbs (5.4 kN-m), or refusal, 3) a minimum pier shaft steel Fy = 70 to 90 ksi (483 to 621 Mpa) and pier helix steel Fy = 80 ksi (552 Mpa), 4) 1.5 to 1.75 inch (38.1 to 44.5 mm) square shafts, 5) smooth shaft surface, 6) the ICC Evaluation Report (ER) number of the manufacturer and 7) the manufacturer ISO 9001 certification for material quality control. Proper installation requires: 1) equipment with sufficient axial compression force (crowd) on the pier shaft so the helix engages the soil and advances to the specified minimum installation torque or refusal, 2) additional specialized techniques for expansive soils and 3) qualified specialty helical pier installation contractors experienced in expansive soils who submit and utilize pier configurations, techniques and equipment that will most effectively and economically meet the specified performance.

Jan 1, 2007

By J. Garvey

The new Cyprus Miami electrolytic copper refinery was commissioned in October 1994. The refinery has been operating at its design capacity of 190,000 short tons per year, and in recent months to 110% of design capacity, producing high-grade electrolytic copper cathodes. Basic and detailed engineering, performed by Fluor Daniel Mining and Minerals, incorporated state-of-the-art technology, including stainless steel cathodes, automated electrode handling, fine-filtering of the commercial electrolyte, autoclave leaching of the anode slimes and other techniques. The major design goals have been safety of operation and quality of the product. Relatively high cathode current densities of 30 amperes per square foot and greater have been applied since start-up. Cathode current efficiencies of over 94% have been achieved since the latter part of 1997. The cathodes were certified on the Comex and LME markets during 1996. ISO- 9002 certification is in progress and should be completed during the first quarter of next year. This report discusses some of the studies that were performed to obtain an optimum layout for efficient materials handling and to create optimum conditions for producing high quality cathodes. A description of the design and operation of the anode slimes facility, including decopperizing with autoclave leaching, is provided. Finally, a description of the start-up experiences and present operation of the electrorefinery are presented.

Jan 1, 1999