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By A. G. Doll

"This paper expands the SAG mill survey database published by the Author at Procemin 2013. The new database includes 49 published SAG/AG mill surveys and includes mills from all over the world. The paper will compare the survey database to SAG mill models by Austin, Morrell and Hogg & Fuerstenau with the purpose of demonstrating the degree of fit of the models to surveys and validating any empirical “fitting factors” used in the models.SAG mill power draw models are used in mill design and grinding circuit modelling to predict how much power will be consumed by a particular mill geometry and operating configuration. The importance of conducting surveys suited to model calibration will be highlighted because the review of literature shows that survey information important to modelling is often missing or omitted. A recommendation for the collection of data during a mill survey is presented, along with some assumptions used by the Author in the absence of certain data. The benefit to mining companies of publishing their survey data, and thereby allowing modellers to improve their model calibration, is discussed.The comparison of models requires a discussion of the measurement of power in a mill drive system as the models use slightly different position in the electrical network for ""where power is measured"". The benchmarking of models against plant operations requires a similar discussion of power measurement."

Jan 1, 2016

By Pierre Rocque

The Red Lake Mine is located approximately 600 km northwest of Thunder Bay. This 545 tpd (600 tons/day) underground narrow vein gold operation is set to produce in excess of 14.8 tonnes (475,000 ounces) in 2001 at a cash operating cost below 75 U$/oz. The high-grade nature of this deposit (>55 g/t or >1.6 opt) coupled with its complex geological environment and relatively deep location dictated the choice of a very selective primary mining method, Mechanized Overhand Cut and Fill. In addition to geological challenges, mine design issues such as material handling, ground stability and requirements for yieldable ground support are also discussed in this paper.

Oct 1, 2001

By Bernard Jones

LTUG ? A meeting of many mining companies that are using large tires ? Introduction of the mines and size ? Companies go over their usage of tires and performance ? As a group we discuss how the manufactures are doing with supplies and performance (who's running what sizes and manufactures they are using) ? The mine's best practices they use (which ones work for them and which ones don't) ? Where the mines see themselves going in the future ? What type of tire management the mines have in place

May 1, 2009

By Jan E. Nesset, Colin Hardie, Peter Radziszewski, Donald P. Leroux

"The successful introduction of new high intensity stirred milling technologies (e.g. IsaMill, SMDetritor) to the mining industry in recent years prompted Noranda-Falconbridge to initiate a study comparing these technologies to the conventional technologies of ball milling and existing vertical stirred mills (e.g. VertiMill). The study was unique in that it utilized the same material (Brunswick Mine zinc cleaner regrind mill feed), the same sizing instrument (a Malvern laser difractometer) and sampling protocol, and media size and type (for the high intensity stirred mills). The paper compares the net energy efficiency (kWh/t) of the various technologies, their power intensity (kW/m3) and product size distribution spread (P80/P20). A key finding is that media size is critical to achieving optimal performance. As part of the performance comparison, an analysis of the four methods of power measurement was made (Prony brake, shaft torque, grinding chamber reaction torque, “no-load” correction) and followed-up with an experimental test procedure using three of these methods. The findings include divergent results for power measurements and some explanations based on the observations are proposed. The direct shaft torque and Prony brake calibration methods are shown to be the methods most suitable for stirred mills.INTRODUCTIONThe motivation for the investigation reported here was the lack of a suitable comparison within the available literature of relative grinding efficiency for the emerging crop of new industrial fine grinding technologies. Such comparisons are potentially fraught with inconsistency, from ore samples and grinding media used, to testing methodology, to size measurement techniques, to the power measurements themselves. The collaboration of the industrial suppliers (at the time MIM Technologies and Svedala, now Xstrada Technologies and Metso Minerals) and McGill University (P. Radsiszewski) were sought in order to ensure as valid a comparison as possible. The work was performed between October 2000 and November 2002, led by the mineral processing group at the Noranda Technology Centre (NTC) in Pointe-Claire, Quebec. The paper is presented in two sections; Part A considers the different power measurement methods and a comparison of the results for the SMDetritor (SMD) technology, while Part B reviews the grinding performance of the 5 technologies investigated using the selected performance criteria."

Jan 1, 2006

Westwood Quebec Long Life, Low Cost CONSTRUCTION UPDATE ? Shaft advanced to 840m (after 1 year), 3 km of down ramp and 2 km of exploration drift ? Head frame and hoist room structure completed ? 2009, 84,700m drilling program completed (increase 9%) 2010 OUTLOOK ? $102 million expenditures planned ? Shaft to advance to 1,300m and the first loading excavate 71,500m drilling program planned

May 1, 2010

By James Ransford Dankwah

This work investigates the effect of waste plastics addition on the reduction of iron oxide by sawdust. Composite pellets of iron oxide containing sawdust (SD), high density polyethylene (HDPE) and blends of SD/HDPE were fired under argon in a horizontal tube furnace at temperatures between 1300 and 1500 °C. Reduced samples were weighed after 10 minutes of reduction and the extent of reduction was calculated from the measured oxygen contents of the compact. The results showed improved extent of reduction when SD was blended with HDPE. The highest extent of reduction was achieved at SD:HDPE ratio of 2:3.

Jan 1, 2014

By Michel Doyon

Canadian Context: Exploration ??Space Exploration is within the unique mandate of the Canadian Space Agency ??Global partnerships ??Maintain close relationship with our partners ??New knowledge in S&T ??Retain and attract highly qualified personnel ??Participation in missions leads to design roles in industry and academia ??Collaboration between government laboratories, industry and academia

May 1, 2009

By Cardm Jeffrey W.

The decay of 222 Rn yields a series of short-lived decay products which become attached to the surface of a plate or wire exposed in a 222Rn-bearing atmosphere. The alpha-activity of two of the decay products, 218Po and 214Po, can be measured by simple counting techniques. This phenomenon may have direct application to uranium exploration. Laboratory studies have shown that: (a) radon decay products can be collected on a wide variety of materials (including various kinds of metals and plastics); (b) activity increases as a function of the surface area of the 'collector; and (c) the collection of the decay products is enhanced by applying a negative charge. The new technique was used in situ to delineate the anomaly above the South March uranium-copper occurrence. A related technique was developed to measure radium in soil samples. The results of both studies compared favourably with those obtained from conventional methods.

Jan 1, 1979

By Transfert Environment and Society

Transfert?s added value ? Building bridges between project promoters and communities ? Unique expertise in working toward Social License to Operate through meaningful community engagement ? 25 years of recognized innovation and a systematic approach ? Key mining clients: ? Royal Nickel Corporation ? IAMGOLD - Niobec ? Richmont Mines - Wasamac ? Mine Arnaud ? Managem

Aug 1, 2013

By R. E. McElvain

"Hydraulic transportation of solids in suspension with water or other carriers, such as oil is becoming more practical as economic situations develop with respect to the railroads and other carriers. Of significant importance, is also the increased size of the major operations and the total impact of larg- er tonnages and more critical sources of supply.There are several means of imparting energy into the solids and directing the material down a pipeline, but the centrifugal pump is emerging as the most practical piece of equipment when considering relatively large flows and recent development. We can now handle relatively high densities without interruptions. This provides the mining and transportation fields a more economical means of lifting and transporting coal and other mineral products.Equipment & MethodsWarman International has developed several methods of alternate PDP against high heads. We have, at least for the present time, shelved our pump which uses clear water to slurry method and have placed our major emphasis on the full development of the centrifugal pump. I personally see several similarities on the alternate reciprocating devices as compared with the steam piston type engine versus steam turbines. The centrifugal pump comes into its most advantageous position at about 2000 GPM and can also show advantages by means of increased mobility, when driving tunnels and in other difficult operations when considering the total economic results. We now have some interesting d<:ta on one 5 mile raw silica sand line designed for pumping at 200-400 tons per h:mr. This is a separate subject on a ""simplified approach to slurry transport"" and paper has been prepared for the Hydrotransport 5 proceedings in Germany this Spring. Reference 1 may be of interest to those who want to delve into the subject further, and I also have some advance copies of this paper."

Jan 1, 1978

By Brian Hart, Hong Zhong, Liuyin Xia, Kyle Douglas

"The application of hydroxamic acid as flotation collectors is fast becoming of significant interest for the selective flotation of oxide minerals along with upgrading oxidised based metal ores and minerals. In the hydroxamate molecule, both O and N atoms in the -CONHOH group are identified as coordination atoms in many complexes and their characteristic structure determines the strength of the chelation complex between the hydroxamate and metal ion. The chelating performance of hydroxamates with transition metals including Cu, Ni, Zn, Fe, Cr, Mn and Co, the alkaline-earth metals (Be, Ca) and heavy metal (Pb) has been studied. Cytec has developed and patented a range of alkyl hydroxamates as flotation collectors for oxidised base metal sulphides, metal oxide minerals and precious metals. This paper introduces two new structures of hydroxamate collectors (Cyclohexyl and 4-tert-butylbenzoyl hydroxamates) and evaluates their characteristics relative to alkyl and benzoyl hydroxamates. Laboratory small-scale flotation tests were conducted with ilmenite and wolframite. The use of 4-tert-butyl benzoyl hydroxamate resulted in a best flotation performance for ilmenite. A relatively low cyclohexyl hydroxamate dosage was required in the flotation of wolframite to obtain comparable results to the alkyl and benzoyl hydroxamates. It is also shown a significantly improved flotation performance with 4-tertbutyl benzoyl hydroxamate in the flotation of ilmenite plant ore in comparison to the oleic acid or fatty acid collectors typically used for ilmenite flotation.INTRODUCTIONHydroxamic acid has been reported as an effective collector in small-scale flotation tests for a wide variety of oxide minerals and ores including copper (Lee et al., 1998, Lee et al., 2009), iron (Quast, 2000), tin (Sreenivas and Padmanabhan, 2002; Wu and Zhu, 2006), tungsten (Marinakis and Kelsall, 1987; Xia et al.,2004), and rare earth metal minerals (Ren et al., 1997; Pradip and Fuerstenau, 1991; Assis et al., 1996; Pavez et al., 1996; Zheng et al., 1996; Chen et al.,2005).As part of our previous research project, a selected suite of hydroxamic acid collectors including fatty, aromatic and modified hydroxamates (naphthoyl, cyclohexyl, benzoyl, octyl, 4-tert-butyl benzoyl, salicylic hydroxamates) were tested in order to examine their potential for recovery and selectivity of rare earth minerals. In these tests it was shown that the flotation performance with the hydroxamate collectors was significantly better than the phosphoric acid collectors on no slimes removed samples (Brian, et al., 2014; Liuyin, et al., 2014 and unpublished internal technical reports). Furthermore the tests revealed that for most of the hydroxamate reagents tested, their dosage requirements to achieve recoveries at the same levels was less than that for the phosphoric acid collectors. Recovery of both La and Ce was significantly better for the salicylic hydroxamate and that Nb, Y and Zr recovery were favoured by the octyl and benzoyl hydroxamates (Brian, et al., 2014; Liuyin, et al., 2014). Comparison among the hydroxamate collectors showed that the flotation and recovery performance of cyclohexyl (CHH) and 4-tert-butyl benzoyl (TBH) was not as good as the other hydroxamates for rare earth recovery."

Jan 1, 2015

By D. Richardson

Presentation Objectives ?Demonstrate the utility of 3D modelling for visualizing exploration data ?Demonstrate the target generation ability of 3D model query methods Exploration Criteria -Example Given the Geology of Sudbury What Are Our Exploration Criteria? (selected examples) ?Geometry ?Trends ?Lithology ?Proximity to Sulphides ?Length and Grade of Anomalous Mineralization ?Distance from Footwall In Addition ?Geophysical Criteria ?Economic Criteria ?Amount of Available Space ? Depth

May 1, 2006

By J. F. Archibald

A research effort has been undertaken, under Workplace Safety and Insurance Board of Ontario (WSIB) sponsorship, to characterize the support capabilities of conventional and innovative spray-on lining materials for mitigating dynamic failure effects created by simulated rockbursts. Conventional spray support media, such as shotcrete and fibrecrete linings, and a variety of new spray-on lining materials [thin, spray-on liners (TSLs)], typically polymer-type thin coatings, were subjected to simulated rockburst influence. For baseline comparison, conventional rockbolt and bolt-and-mesh support products were also evaluated. Observation of lining performance was undertaken through completion of field-scale support and rock detonation trials. Controlled blasting tests were conducted at the Queen’s University Explosives Laboratory to examine the effectiveness of the variety of surface coating agents for modifying dynamic rock spalling processes. All tests were performed upon largely undisturbed and homogeneous rock materials in highly repeatable fashion. All blasts were observed seismically and photographically to provide detailed information concerning rock motion, surface fracturing, ejected fragment motion and support liner survivability characteristics. These material comparison trials were performed to assess the relative effectiveness of a wide range of currently available area support techniques for suppressing hazards associated with dynamic rock ejection. The results of this study validate that thin, spray-on linings may be equally as effective, and often better, than conventional support materials at mitigating rockburst or like damage in highly stressed mine environments.

Jan 1, 2004

By M. Melashvili

"The SART Process was introduced to the gold mining industry in the late 1990s and several commercial plants were built over the following 10 to 15 years. Most of these plants have operated well and enjoyed plant performance in line with expectations based on the underlying chemistry of the process. However, two of the plants have consistently suffered from high reagent consumption and poor product quality, which has motivated a re-examination of the process fundamentals in the hope of understanding the reasons for poor performance when it occurs, and developing mitigating strategies.This testwork along with a review of the relevant literature has demonstrated that the amount of sulphide added to the primary reactor, relative to the copper concentration, is the most critical parameter dictating plant performance, with pH and residence time important secondary factors. The primary product in the SART Process is synthetic chalcocite, Cu2S, and the stoichiometric requirement for sulphide addition is therefore 0.5 moles per mole of copper in solution. Testwork shows that when sulphide is added in excess of this amount (generally with the express purpose of lowering residual copper in solution) it not only fails in its intended purpose, but can have a negative impact on the settling and filtration characteristics of the copper sulphide product, as well as the final product quality. Moreover, these problems are exacerbated the higher the selected operating pH in the pH 3 to 5 range, and the longer the residence time of slurry in this pH range.Freshly precipitated copper sulphide compounds are known to be very fine and slimy, with poor settling and filtration characteristics. It is therefore important to engineer the SART Process in such a way as to encourage growth in the average particle size of the precipitate crystals. This was the rationale for recycling a portion of the thickener underflow to the primary reactor when the SART Process was developed. The theory of crystallization predicts that compounds of extremely low solubility, such as chalcocite (Cu2S: KSP = 10-48), are likely to experience growth in crystal particle size through aggregation rather than heterogeneous nucleation. On this basis, the SART practice of recycling a portion of thickener underflow to the primary reactor in the commercial plants is unlikely to lead to crystal growth via nucleation, and could in fact promote breakage of the aggregates that formed in the thickener. Recycling thickener underflow could therefore have the opposite of the desired outcome. The result of testwork that is reported here lends credence to this theory and questions the wisdom of recycling in the SART process.There is evidence to suggest that operating the copper sulphide thickener in the SART Process without flocculants may be beneficial. Thickener underflow densities could improve from the current 10 - 15% range to 40 - 50%. This will not only reduce the flowrate of slurry to the filter, but the filtration properties of the slurry (filtration rate, filter cake moisture content) will also improve. This is one of the most critical engineering and design aspects of the SART Process, and the achievement of high solids density in the thickener underflow will not only improve the health and safety aspects of the operation, but also has the potential to lower capital costs and improve the quality of the final product."

Jan 1, 2016

By Mehmet Canbazoglu, Kaarlo Haavanlammi, Hannu Laitala

Cobalt is currently a critical metal because of the increasing number of electrical vehicles forecast for production. Copper and zinc are base metals that are used in many everyday applications, including vehicle production. Eti Bakir Co. Mazidagi Phosphate Plants in the Mazidagi district of Mardin, Turkey is a multi-product facility that produces cobalt, copper, and zinc, as well as fertilizers, from the roaster calcine. Roaster off gas is treated in a sulfuric acid plant (SAP) and the acid itself is utilized in fertilizer production. The comminution circuit, roaster, SAP, and calcine leaching process were developed by Outotec and integrated with the fertilizer production process implemented by Eti Bakir A.Ş. This paper describes the hydrometallurgical calcine leaching process used at the plant, with a focus on the oxidative pressure leaching of the cobalt, zinc, and copper-containing calcine. The cold and hot commissioning phases of the pressure leaching autoclave start-up are discussed together with experiences from the ramp-up period. The production processes of the copper cathode and cobalt and zinc-containing salts are also presented together with some of the plant’s operating parameters. INTRODUCTION The ETI Bakir A.S. fertilizer plant, Turkey, is located in Mardin Province near the border with Syria, (Figure 1). The leaching plant project was started in 2012. The purpose of the plant is to separate the valuable metals from the calcine produced by the pyrite roasters, which are used to produce a SO2 containing gas for the new sulfuric acid plant. Fertilizer production requires sulfuric acid, and for this reason a sulfuric acid plant was built; customer already had access to pyrite concentrate, which is used as the roaster feed. During the engineering phase of the roaster and acid plants it was noticed that the roasted calcine contained considerable amounts of valuable metals like cobalt, copper, and zinc. To recover these metals, a calcine leaching process was developed at the Outotec Research Center in Pori, Finland. The main process connections of the Mazidagi site are shown in Figure 2.

Jan 1, 2019

By Patrick Pelletier, Pierre-Alexandre Bossé, Julie Fournier, Gianni Bartolacci, Jayson Tessier, Ahmed Bouajila, Carl Duchesne

"This paper summarizes research into the study of the control of flotation processes based on froth images. The use of numerical image analysis techniques for the extraction of significant patterns (froth structure and colour) from industrial flotation froths is discussed.First, the froth was analysed by the use of the Multivariate Image Analysis (MIA) method to extract the spectral variation contained in a RBG image. The Partial Least Squares (PLS) was applied to develop the empirical model for the prediction of froth grade. The results of this application are illustrated using one industrial case study.Second, the froth was also analysed by Gray Level Co-occurrence Matrix (GLCM) and Wavelet Transform Analysis (WTA) to extract features related more to morphological aspects. Since there is useful information hidden in froth texture, these methods are used as texture descriptor to classify different types of froths.Third, a control strategy based on a froth structure indicator was developed and implemented on an industrial zinc flotation circuit. The feedback controller uses a reagent flow-rate in order to maintain the froth structure at its set point. Process improvements obtained with the implemented control strategy are highlighted.Finally, the feasibility to implement a hybrid control strategy consisting in a froth structure supervision controller based on the froth concentrate grade estimated by MIA and recovery inferred by image analysis is discussed.INTRODUCTIONThe development of control strategies to achieve satisfactory control performance has always been a great challenge for engineers and the need for improved process diagnosis, control and optimization has become more and more evident for the mineral processing industry in the last decades. That is why new process variables need to be measured particularly in highly multivariable processes such as flotation. This industrial process is subject to a wide variety of disturbances mainly generated by frequent and sometimes abrupt changes in physical and/or chemical ore characteristics and also, due to some irregularities in manual process operating procedures. A flotation circuit scheme is always a complex network of more than two dozens slurry streams. Information about those streams (% solid, metal content analysis and flow rates) is important for process diagnosis performance evaluation and control. Also, because of the grade decrease and increasing complexity of the new processed ores, more instrumentation outputs and more powerful and significant pr"

Jan 1, 2005

By Benoit Bissonnette

"The need for production of a competent fill was recognized early by the project partners. Consequently, a 4000 Ud paste fill plant was constructed and commissioned in early August 1994.In order to fine tune the process without risk to the underground workings, a closed pumping loop was devised on surface. After two months of this exercise, the first underground slope was filled according to specifications obtained from the pilot plant trials.This paper will focus on the operational problems encountered and the solutions adopted so far, and on a comparison between expected and actual fill production and characteristics.RésuméLa nécessité de produire un remblai de propriétés mécaniques suffisantes a été rapidement reconnue par les partenaires du projet. Conséquemment, une usine de production de remblai en pate, utilisant les residus du concentrateur d'une capacité de 4000 t/j a été construite et l'opération a débuté au mois d'aôut 1994.Dans le but de roder le précedé sans mettre en danger les installations souterraines, l'usine a été testée dans un circuit de surface. Après deux mois d'essais, le premier chantier souterrain a été rempli avec du remblai en pate selon les specifications dérivées de l'usinage pilote.Cet article présente les problemes d'opération rencontrés et leurs solutions, en plus de faire une comparaison entre les résultats prévus et ceux actuellement obtenus sur la production et sur les charactéristiques du remblai."

Jan 1, 1996

By E. H. Smith

"The El Indio mine treats a complex mixture of copper and gold/silver ores at its plant located in the high Andes in Chile. The plant utilizes conventional crushing, grinding and flotation to produce a copper/gold/silver concentrate. Due to high levels of arsenic and antimony, the flotation concentrate must be roasted prior to custom smelting. The flotation tailings is leached and additional gold recovered from a CIP circuit. Present and future metallurgical developments are discussed in this paper. INTRODUCTIONIn late 1989, LAC Minerals purchased 65 % of Bond International Gold and as a result became controlling shareholder of the El Indio Mine through Bond and San Jose.El Indio is a world class, complex sulphide gold deposit located in the hydrothermal alteration belt of the Andes mountains in the 4th Region of Chile. The mine is located in the high Andes about 185 km east of La Serena at an elevation of 4000 meters. The 1450 workers at El Indio live in the mine camp at 3200 m and on days off are bussed to La Serena.The El Indio mine was started in 1979 by St. Joe Minerals Corp., bought by Bond in 1987 and subsequently by LAC in 1989. The mine has produced 2.7 million oz. of gold, 9.5 million oz. of silver and 170,000 t of copper since start of operation. The mill is currently operating at a rate of 2850 t/d and producing a copper/gold concentrate which is roasted to produce a copper/gold calcine and high quality, saleable crude AS2O3 . A small proportion of the precious metals are also produced as bullion from the leach circuit.Total production during 1989 was 224,197 ounces of gold, 1,309,342 ounces of silver and 26,968 tonnes of copper. The average cash cost of production for the period was U.S. $96 per ounce of gold, net of by-product credits. The average realized price was $5. 30 per ounce of silver and $1.14 per pound of copper."

Jan 1, 1991

By J. Maheu

Heap leaching is an old technique for the recovery of copper, but a fairly new technique for the recovery of gold.The paper outlines the equipment required for the establishment of heap leaching test facilities and the procedure required to insure meaningful results. Sampling methods, the metal balance, carbon adsorption and stripping and safety procedures are discussed in broad outline.

Jan 1, 1982

By A. I. Collins, D. Danninger

Newmont has installed advanced control and online optimization on the dry grinding circuit and both roasters on its Carlin Trend refractory ore treatment plant. Subsequently, Newmont has developed a master plan for institutionalizing advanced control and optimization on all its processing units. Newmont is committed to a program of applying advanced control and optimization from crushing of ore to pouring of gold. This paper describes Newmont&apos;s experience with implementing advanced control and optimization and the benefits received. In addition, identification of advanced control and optimization opportunities and their economic justification is discussed.

Jan 1, 2005