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By A. O. Dufresne

A Step which, it is believed, will prove extremely beneficial to the Quebec asbestos-mining industry was taken during 1931, when the asbestos mine operators of the Province assembled to work out a uniform method of naming the products of their mines. The outcome of several meetings was the drawing-up of a classification which defined, limited, and designated anew the numerous grades of asbestos marketed. It entailed no drastic departure from the existing processes of grading, nor any revolutionary changes in methods of testing, but aimed rather to perfect existing methods. The classification proposed has been accepted by all operators in the Province, who, from January first of this year, began introducing the new nomenclature. Unless one is conversant with the properties and mode of occurrence of chrysotile asbestos, with the unique milling methods devised for its recovery, and with the history of the development of their technique, he may not readily understand the basis of the new classification. For information on these and other data concerning the industry, the reader is referred to a recent publication, Chrysotile Asbestos in (Canada, by James Gordon Ross, issued by the Mines. Branch of the Department of Mines, Ottawa. The object of this paper is to present briefly some of the phases in the evolution of the classification of Canadian chrysotile asbestos, in the hope that the recent effort to standardize the marketable products of one of Canada's most important non-metallic mineral industries will open a field for discussion, fruitful in new ideas and constructive suggestions. The necessity for the grading of asbestos results fundamentally from the fact that the price per ton depends on the length of fibre. At all times in the history of the industry, the very limited available supply of the longer grades, as well as the requirements of the trade, have caused relatively very high prices to be paid for fibre over half an inch in length, while for the shorter grades the price decreases rapidly, and at a rate which bears no proportionate relation to the length of fibre.

Jan 1, 1932

By J. S. Stachulak, K. A. Mackinnon

This paper deals with specifying and evaluating fans for mine ventilation projects. Topics such as fan and equipment design life, operating points, and operating conditions are discussed. Common operating problems, such as vibration, parallel operation, mechanical failure, erosion, corrosion, and deficient fan performance are covered. Apart from identifying the potential operating problems, likely causes and suggested remedies are given. Fan type, fan accessories, and likely system effects and fan testing are discussed. Suggestions on what should be covered when evaluating different fan options and proposals and suggestions on the verification of supplier claims and guarantees, including cost of operation, the evaluation of initial capital cost, estimate on maintenance costs, and likely replacement expenditure over the life of the fans. In addition, fan reliability, operational flexibility, suggested construction details and fan vendor past history and experience are reviewed.

Jan 1, 2004

By A S. Leitch

This paper is based on the accident prevention pro-gram carried out in the coal mines of Alberta. It defines the role of the Alberta Mines Branch and of The Work-men's Compensation Board, and relates how a safety pro-gram was initiated. The formation of the Alberta Class 1 Mining Safety Council is also described. The responsibilities of both management and the individual worker are then outlined, and the main features of a successful accident prevention program are delineated. T HE purpose of this paper is not to repeat generalities and platitudes about industrial safety, but rather to relate the experience of Alberta coal mines during the past number of years in their efforts to keep accidents to a minimum. It has been learned from experience that many basic principles are as sound today as they were 20 years ago. How-ever the complexities of modern mining methods and the modern man or miner have created problems that did not exist then.

Jan 1, 1964

By Jr. Blanchette, Claude Bazin, Paul Blatter

"Reporting of the gold production during a month implies to estimate the mass of gold that is processed by a mill, recovered as dorés, lost to the tailings and the change of gold inventory within the plant equipments. Carbon in pulp and/or carbon in leach tanks may contain gold inventory as large as 72 000 g (2 200 troy oz) of gold which needs to be estimated from measurements obtained from sampling the material contained in a tank. Sampling and analysis introduce measurement errors that could be systematic and/or random. This paper examines the effect of measurement errors on the estimation of the gold inventory and on the variation of the inventory in the carbon in leach tanks of the Agnico-Eagle Mines Limited Lapa concentrator. Results of the analysis demonstrate that the inventory is measured with ±10% reproducibility, while the variation of inventory used for mass balance is known with ±300% reproducibility.INTRODUCTIONThe preparation of a production report implies to reconcile measured data with the constraint of material balance over the considered period of production. The sampling and data reconciliation problems were recently reviewed by Morrison (2008) and Jansen (2009a; 2009b). Typically a production report is prepared to cover a period over which the mass conservation hypothesis can be considered valid. In gold processing plants, the change of inventory can seldom be neglected and plays a significant role in material balance calculations. This is particularly true for circuits using carbon adsorption, where the complete cycle of carbon is measured in days.In a 2000 t/d gold ore processing plant, the inventory can be as large as 140 000 g of gold in gravity concentrator bins, carbon in pulp tanks and in the electrolysis circuit. This is equivalent to the mass of gold that fed the circuit during 10 days of operation with 7 g/t feed assays. The change of inventory may therefore strongly impact the production figures and especially the plant recovery at the end of a week or a month. Despite the financial impact associated with gold inventory, few publications are devoted to the subject. Bruington (1991) and Morrison (2008) discussed the problem and stressed the need for the development of reliable methods to estimate the gold inventory in carbon in pulp or carbon in leach circuits."

Jan 1, 2011

By R. Grimard, M. Gamache, L. -P. Bigras, P. Cohen

This paper describes a real-time fleet management system for an undergroun mine. Dispatching, routing and scheduling are handled simultaneously, taking into account the mine status, operational constraints and vehicle location information. Each assignment decision takes into account the traffic on the road segments of the mine network, whether road segments are bi-directional or uni-directional, and ensures that each LHD (load-haul-dump) vehicle arrives at loading and dumping points with the correct orientation. Such a system can be used either as a simulation tool for strategic planning or as a real-time managing and optimizing system for operations. In the simulation mode, the system can accurately estimate the impact on productivity of decisions such as the development of waiting areas (bays, sidings), or the addition (elimination) of vehicles to the fleet in operation. When used for real-time dispatching, routing and scheduling of vehicles, the system can optimize production with respect to various assignment criteria such as cycle-time minimization or deviation from a target production plan.

Jan 1, 2004

By Kathleen A. Altman

"This paper supplements the information provided annually at the Canadian Mineral Processors Operators Conference regarding the education of Mineral Processors in Canada. The purpose of the paper is to provide information regarding the engineering accreditation process in the United States and the universities that offer programs in Mineral Processing and Extractive Metallurgy in the U.S.There is a critical shortage of trained Mineral Processors and Mining Engineers world wide. The Society for Mining, Metallurgy and Exploration (SME) formed a task force to evaluate the national needs for trained engineers and to track the number of engineers who graduate from U.S. universities each year. The statistical information for Mining Engineers is well-developed. The current effort is to assemble similar information regarding students who graduate with expertise in Extractive Metallurgy and Mineral Processing as well as to explore the limitations of the accreditation system in the United States and its impact on the education of Mineral Processors. The long-term objective is to develop a data base regarding Mineral Processing programs and Mineral Processing graduates that is as complete as the one that has been maintained by the Canadian Mineral Processors.INTRODUCTIONIn the United States engineering curricula are accredited by ABET, which was formerly known as the Accreditation Board for Engineering and Technology. The objective of ABET accreditation is to ensure that educational programs in applied science, computing, engineering and technology meet quality standards set in conjunction with the professional organizations that represent professionals in the industries which hire students graduating from those educational programs. For example, the Society for Mining, Metallurgy and Exploration (SME) is the lead society for accrediting Mining Engineering programs in the U.S. For Materials Science and Metallurgical Engineering programs, the lead society is The Mineral, Metals and Materials Society (TMS). SME is a cooperating society for accrediting Metallurgical Engineering programs. Cooperating societies for the accreditation of Materials Engineering include the National Institute of Ceramic Engineers (NICE), the American Institute of Chemical Engineers (AIChE) and the American Society of Mechanical Engineers (ASME)."

Jan 1, 2008

By P. Toscano

The objective of this investigation was to determine how the losses of nickel, copper and cobalt in fayalite slags could be controlled for nickel mattes with iron contents below 5 wt%. Laboratory-converting and slag-cleaning experiments were carried out at 1250°C. Several variables were investigated during and after converting to help minimize the amount of nickel and cobalt that reports to the slag. The variables used were oxygen concentration in the blast, coke breeze addition and nitrogen injection stirring. In all the experiments, slag and matte co-existed. Coke additions during converting have little effect on the losses of nickel, copper and cobalt. In fact, coke additions retard the converting process by consuming some of the oxygen injected. On the other hand, coke additions and nitrogen injection applied after converting was completed resulted in decreased slag losses.

Jan 1, 2004

By P. Toscano, T. A. Utigard

"The objective of this investigation was to determine how the losses of nickel, copper and cobalt in fayalite slags could be controlled for nickel mattes with iron contents below 5 wt%. Laboratory-converting and slag-cleaning experiments were carried out at 1250°C.Several variables were investigated during and after converting to help minimize the amount of nickel and cobalt that reports to the slag. The variables used were oxygen concentration in the blast, coke breeze addition and nitrogen injection stirring. In all the experiments, slag and matte co-existed.Coke additions during converting have little effect on the losses of nickel, copper and cobalt. In fact, coke additions retard the converting process by consuming some of the oxygen injected. On the other hand, coke additions and nitrogen injection applied after converting was completed resulted in decreased slag losses."

Jan 1, 2004

By Yannis Faitakis, Simon Bergeron

"This paper describes the implementation of model-based predictive control (MPC) on a vacuum heat exchange network at Alcan's Jonquière Complex. The plant produces alumina from bauxite ore using the Bayer Process.The MPC system was commissioned in 2000, by Alcan personnel and an Advanced Control Engineer from Matrikon. The application has achieved an uptime of about 97%.The benefits were:• Energy savings : 0.5% - live steam reduction• Reduced variation: standard deviation of key temperatures reduced by 50%• Plant throughput increase: via the automated use of surge tanks• Decreased supervision time: by plant operations• Faster and easier diagnosis of problems and plant constraintsThe benefits were higher than expected with a payback time around 12 months.The purpose of the vacuum heat exchange network is to recover energy from a hot stream (pregnant liquor) by transferring it to a cold stream (spent liquor). The system is very tightly coupled, and the main constraints of the multivariable control system are: • to control the many tank levels involved in the process (8 tanks)• to maximize the temperature of the heated streams (spent liquor)• to prevent cooled streams (pregnant liquor) from cooling to below a minimum temperatureThe system includes 9 manipulated, 14 controlled and 2 feedforward variables.The advanced control implementation runs under an expert system environment and provides added flexibility to the overall control strategy."

Jan 1, 2003

By Carlos Avalos Casillas, Saul Ortiz Landeros

The current work shows metallurgical results obtained at the Centro de Investigación y Desarrollo Tecnológico (Peñoles CIDT), as a continuation of the work first published in February 2012. With the aim of optimizing the economic values of the products, ores from San Julian (Fresnillo) were selectively floated to produce a lead concentrate and a zinc concentrate containing high silver values. In the laboratory, this included regrinding of the rougher and scavenger lead concentrate to increase the liberation of mineralogical species and thus lower zinc recovery. Cyanide leaching bottle tests were conducted to improve the value of the silver. It is proposed to leach the silver contained in the zinc concentrate and then recover the silver using the Merrill Crowe process. The results show a reduction of zinc recovery in the lead concentrate from 11.3% to 2.0% after regrinding to a P80 of 10 microns, improving the metallurgical quality and economic value of the lead and zinc concentrates. Also laboratory and pilot scale cyanidation tests showed that about 65 to 80% of silver will be leached from the zinc concentrate, after regrinding to a P80 of 10 microns. The proposed processing increases the economic recovery of silver from 72.7% to 78.8%.

Jan 1, 2014

By P. K. Naik, B. Das

Flotation studies were carried out to recover carbon values from blast furnace flue dust containing ~30.34% carbon, 4.6% volatile matter (VM), and 65.03% ash. The variables chosen for the experiments were dispersant (sodium hexametaphosphate), pH, collector (diesel oil), and frother (MIBC). The experiments were designed according to a 24 full factorial design method and regression equations for the recovery of carbon and product grade were determined from the data. Experiments were performed to optimize recovery and grade using the steepest ascent method. The maximum recovery of carbon was 90.0% with a concentration of 56.5%, whereas the maximum obtainable grade of carbon was 66.35% with 50.45% recovery.

Jan 1, 2005

By F. Lindroos

A cornerstone in the LKAB Green Pellet concept is to produce pellets with a small footprint in terms of energy con-sumption, CO2 emission and emission of other elements harmful to the environment, like dust, sulphur dioxides, nitrogen oxides, chloride and fluorine. The concept also encompasses our determination to make pellet products that contribute to low environmental impact and low energy consumption in our customer?s processes. The presentation will focus on the pelletizing process. It will describe both how we have attempted to decrease the generation of unwanted components in the process gas, and how we have tested or evaluated equipment for external gas cleaning. We will discuss and give examples from recent and on-going efforts and outline some of the future challenges we see, to meet our own environmental standards and also the tough demands imposed by EU and national legislation, while striving to boost production.

May 1, 2011

By P. Wells, P. Quinn

"A moveable flotation miniplant was designed and constructed at the research laboratory of Inco Technical Services Ltd. to address the need for flowsheet development with a limited amount of ore (such as drill cores). It consists of one rod mill, two regrind ball mills, one vibratory screen, 24 flotation cells of various sizes and two Venturi aerated flotation columns. The setup has continuous monitoring capability for pH, dissolved oxygen, oxidation-reduction potential, conductivity and temperature in conditioning tanks and flotation cells. Various options regarding flotation reagents, circuit configurations, and fineness of primary grind and regrind can be readily evaluated. The throughput of the miniplant is 20 – 30 kg/hour ore.Unit operations such as flash flotation, magnetic separation and gravity concentration can also be evaluated as an integral part of an entire flowsheet development.This communication describes the basic design features of the miniplant and some examples of applications are given.INTRODUCTIONInco operates numerous mines in Sudbury and Thompson and will shortly bring the Voisey’s Bay mine into production. It has long been recognized that the ores from different mines or from different depths of the same mine can give different responses in flotation. There is a growing need to properly evaluate the ores before feeding the mill to maximize the return of the mine/mill operation. Inco Technical Services Limited at Sheridan Park, Mississauga, Ontario has developed a batch laboratory procedure to address this issue. The results are considered in the overall economical assessment of new mine operations.For ores that cannot be processed by the existing mill operations or that will be processed by a new mill, it is necessary to develop a flowsheet that can maximize the economical return of the mine/mill operation. While recognizing the importance and contribution of the laboratory batch flotation procedure, it does not generate reliable data for flowsheet simulation and design. A full-scale pilot plant campaign is normally required to obtain the design data but often this is not possible due to a limited amount of ore obtainable from the drill core. A small-scale pilot plant (mini pilot plant or miniplant) capable of processing 20-30 kg/h ore can provide this data prior to a full-scale pilot plant campaign. A miniplant can also be used to optimize the circuit configurations, reagent additions and recycle options of process water before pilot plant work and can be used to test a different flowsheet configuration for an existing mill before re-piping a plant circuit."

Jan 1, 2003

By L. Parthasarathy, S. K. Pan, M. P. Srivastava

"Total iron ore reserves in India, as reported by the Indian Bureau of mines, are 23.6 billion tons. Hematite iron ore reserves constitute about 45 % of the total reserve. If we go by the National Steel Policy-2005 projections, India’s supply of hematite iron ore would not last more than 40 years. Laboratory investigations were carried out for the development of a process flow sheet for treating low grade as well as Banded Hematite Quartzite (BHQ) iron ore. The purpose of these investigations was to aim for better resource utilization.Beneficiation studies were conducted on samples of low grade and siliceous iron ore from the Dalli mines, a captive mine of the Bhilai Steel Plant and BHQ ore from Southern states of India. The process flowsheet, developed for upgrading of low grade iron ore, incorporates wet screening of the ore at 0.5 mm, followed by grinding of the +0.5 mm fraction to below 0.5 mm. The whole –0.5 mm fraction, after grinding, was treated in a conventional hydro-cyclone and stub cyclone followed by treatment in Wet High Intensity Magnetic Separator (WHIMS). This resulted in a concentrate product having >66% Fe content from a feed containing 55.5% Fe with an iron recovery of 48 %. The process flowsheet developed for treating BHQ ore in the laboratory resulted in an increase in iron grade in the concentrate from 43.4 to 61.3 Fe % with a yield of 51.7 % .INTRODUCTIONThe classification of Indian iron ore resources have been made compatible with United Nations Framework Classification (UNFC), which is more scientific and has been adopted in most countries in the world. Iron ore reserves and resources estimated using the UNFC classification system, as of April 01,2000 are about 12,906 million tons of hematite ore and 10,628 million tons of magnetite ore. The Indian Bureau of Mines (IBM) has given a breakdown of these reserves by designation as either lumps or fines of hematite iron ore (Table 1). The percentage of the reserves reported lumps and fines are 42 and 34% of the total reserves respectively. High grade iron ore is less than 10% of the total reserve."

Jan 1, 2008

By J. R. Goode

"The Las Cristinas deposit contains about 10.2 million ounces of gold at a grade of 1.3 g/t. The deposit comprises a layer of fully oxidized saprolite (SAPO), a layer of sulphide-enriched saprolite (SAPS), carbonate leached bedrock (CLB) and carbonate stable or un-leached bedrock (CSB). Gold occurs at about the same level in all lithological groups. The bedrock units contain minor amounts of copper (about 0.1%) as chalcopyrite, while SAPO contains virtually no copper it having been leached and deposited in the SAPS zone.A previous owner started investigation of the Las Cristinas deposit in Venezuela in 1991. Over the next seven years, 1174 holes with a total length of 159 km were drilled, extensive metallurgical testwork, including pilot plant operations, were conducted and feasibility studies were completed. Construction was started in 1997 and again in 1999 but was suspended.Crystallex has been producing gold in Venezuela since the early 1990’s. In 1997, Crystallex acquired Inversora Mael which had held two of the claims to the Las Cristinas concessions since 1986. In September 2002, Crystallex entered into a definitive agreement with the Corporación Venezolana de Guayana, (CVG), to develop the Las Cristinas deposit.An extensive program of studies and testwork was started in early 2003 to determine an optimum development plan for Las Cristinas. Mine Development Associates, SNC–Lavalin Engineers and Constructors, SGS Lakefield Research Limited, J.R. Goode and Associates, and Professor A. Laplante at McGill University acted as the main contractors.Because of the potential value of by-product copper, earlier flowsheets used carbon-in-leach for SAPO, but processed all other ore types by flotation to produce a gold-copper concentrate with cyanide leaching of cleaner tailings to maximize gold recovery. Cyanide recovery was necessitated by the high copper content of the leach feed. Initial studies of available data by Crystallex revealed that direct leaching of all ore types would provide about 11% more gold recovery than the previously selected flotation route with reduced capital and operating costs.Bench and pilot scale studies have confirmed that a SAG-ball mill-gravity-CIL route is very effective for all ore types and will give about 89% gold recovery. This paper describes the recent testwork, discusses the proposed plant design, and presents economic data."

Jan 1, 2004

By K. L. C. Gonçalves, V. K. Alves

"CVRD’s Department of Development and Technology – GETEK has been developing and perfecting a general methodology for scaling up flotation and grinding circuits over several years. This methodology has been applied in several prospective CVRD mining projects. It encompasses a procedure for variability analysis based on bench scale tests, pilot scale grinding and flotation tests and modeling and simulation for scaling up the industrial flowsheet.The bench scale tests include the determination of the Work Index, simplified DWT tests, rougher flotation and locked-cycle tests with samples that are representative of the ore body variability. After completion of these studies, continuous, pilot-scale flotation tests are carried out at a Mini Pilot Plant with drill core samples representative of different stages of the mine life. Finally, studies are carried out with large volume samples using a conventional grinding and flotation pilot plant. This sample is also used for liberation characterization, grinding kinetics, flotation kinetics and industrial circuit scale up. This methodology has been successfully employed in the development of CVRD’s new mining projectINTRODUCTIONCVRD has been developing and perfecting a general methodology for scaling up flotation and grinding circuits over several years. The definition of the processing route and the sizing and scale up of the processing system are some of the products generated during the pre-feasibility of a greenfield project. This paper is focused on the scale up of grinding and flotation circuits, operations known to be of the most importance in a mineral processing plant.The methodology for the definition of the flotation and grinding circuits is divided in the following stages: bench scale ore variability studies, pilot plant operation and modeling followed by simulation. The product of this work is a calibrated simulator that can be utilized for plant operation as well as mine planning, looking to achieve optimal operational conditions.The current models used for scale up of the grinding circuits are aimed at the generating information about the size distribution of the circuit product. However, it is well known that the liberation state of these products may be of critical importance for the performance of the concentration processes downstream. Nevertheless, CVRD has been developing a methodology for liberation kinetics during grinding, aimed at optimizing grinding circuit throughput together with downstream flotation recovery."

Jan 1, 2006

By M. J. Allan

"The paper describes the author's experiences in the startup of autogenous and semiautogenous grinding circuits gained over the last twenty years on both large and small grinding circuits. Typical phases in commissioning from construction to startup with ore are covered. The paper also describes experiences with material handling systems, slurry pumping, vibrating screens, trommel screens and pebbles crushing systems. INTRODUCTIONThe commissioning of any new mineral processing plant is an important and exciting milestone in any project. It is at this point in time that the efforts of developers, design engineers, equipment suppliers and operators culminate in a finished product. The successful completion of any project requires that the plant achieve design throughput as quickly as possible. The success of any startup can generally be anticipated by the amount of careful planning which takes place before equipment is operated. The first part of this paper describes the steps in going from construction through to introduction of ore. The organization and planning of startup activities is also covered.The second part of this paper describes some typical problem areas and past experiences in the startup of semi-autogenous grinding circuits. Semi-autogenous grinding circuits present some special challenges in the startup phase. The description of some of these problems and experiences will hopefully provide other operators with suggestions on how to avoid (or at least prepare for) these problems."

Jan 1, 1992

By Mario E. Rossi

The full economic evaluation of a mining project requires a block model that provides an estimate of the tons and grades of available resources. The model must be representative of the mineralization to be found at the time of mining for specified extraction periods and within acceptable error margins. In an operating mine, there may be a reasonable understanding and estimates of actual dilution and ore loss. This paper discusses the issue from the perspective of a project at a feasibility or preproduction level of development. Three types of dilution are discussed. Internal dilution (or change of support) is function of the spatial distribution of the mineralization and its relation to the operation?s selectivity. Geologic contact dilution is the unavoidable mixture at contacts or boundaries of material with different geologic characteristics, grades, or metallurgical performance. Operational planned and unplanned dilution should also be considered, sometimes incorporated by factoring the resource model, but more accurately by mimicking the grade control process. The resource estimation process always carries uncertainty, which is sometimes significant, and usually caused by several factors. These include quantity and quality of drill hole information; quantity and quality of geologic data; grade estimation methodology; dilution and mining recovery factors applied; etc. A key decision is to whether estimate as accurately as possible the in-situ geologic resource or to estimate the tons and grade of the material to be fed to the processing plant. The geologic modeling and grade estimation methods used are conditioned by this decision.

May 1, 2009

By Jim Truskoski, Alain Bouchard, Andy Kerr, Germain Labonté, Jim Barrett

"Improving mill grade recovery relationships is always good business. INCO’s Clarabelle Mill has just undergone a $16 million process upgrade that was designed to improve nickel recovery by 2%. The “Mill Redesign Project” was completed on time, under budget and delivered the promised improvement in recoveries.This paper describes the methodology of the Mill Redesign Team, details of the process improvements and the critical success factors that helped the team deliver on its promises.With a payback of under one year, the Mill Redesign Project will play a key role in ensuring a competitive edge as INCO embarks on its second century of operation.INTRODUCTIONIt is not uncommon in milling operations to encounter a crisis. That is the point when the process does not behave as expected and fails to respond to the increasingly desperate efforts of the metallurgists and operators. Flowsheet and process changes are attempted and abandoned. With luck, one or more of the changes achieves some mitigation of the original problem or more usually, the original cause of the problem disappears. Regardless, the metallurgist can sit back and bask in the apparent success of his or her endeavours.Less common is when a problem is carefully diagnosed, a team put together to explore all avenues and recommend a path of action that is implemented on time, on budget and immediately delivers on the promises which are sustained over time. This is one such story. It is the story of the Mill Redesign Project at INCO’s Clarabelle Mill in Copper Cliff, Ontario.BACKGROUNDThe Clarabelle Mill was built in 1971 on the southern rim of the Sudbury basin. At that time it was one of four mills operated by INCO in the Sudbury area. During the 1970’s, 80’s and 90’s, the need for increased process efficiency, higher levels of sulphur rejection to tails and the concurrent development of high capacity mills and flotation cells, resulted in the consolidation of INCO’s Sudbury area milling operations into a single, expanded facility at Clarabelle."

Jan 1, 2003

By David Meadows, John Starkey

"As part of the ongoing project development for the Tenke Fungurume Copper-Cobalt Project in the Democratic Republic of Congo, Phelps Dodge Corporation has examined methodologies for determining the size of grinding mills to support a 7000 mtpd operation. Six samples were tested by Hazen Research, Inc. (HRI) to obtain the JK parameters using the JK Drop Weight Test, standard Bond crushing, and rod mill work indices, abrasion indices and by Dawson for Bond Ball Mill Work Index tests using crushed feed, and Standard Autogenous Grinding Design (SAGDesign) Tests, patented by Outokumpu. (See reference 8 below).The comparison of these results gives context to how the various measurements relate to each other and how they can be used to obtain an accurate design for the grinding mills required for the Tenke Project. This is the first published direct comparison between JK Drop Weight, standard bond work indices, and SAGDesign test results. The SAGDesign test includes a SAG test followed by a Bond BM Wi test done on SAG ground material.INTRODUCTIONAfter the presentation of the paper “SAGDesign Testing – What It Is and Why It Works” at the recently concluded SAG 2006 Conference in Vancouver, a question was asked about how SAGDesign ore hardness measurements compared with other comminution tests, specifically the JK Drop Weight Test and the parameters that are derived from such testing. At that time it was noted that a paper was being prepared for the CMP Conference in January to show how various ore hardness measurements compare with each other when done on the same samples.This paper will therefore present the first such comparison using test results from the Phelps Dodge Tenke Fungurume Project where six composite samples were examined by the tests noted below. A seventh sample was tested at Dawson but not at other labs. The tests were done at four different laboratories listed below and included the tests shown."

Jan 1, 2007