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By R. Binning

"Economic high density mineral reclamation and subsequent transportation of solids through a pipeline presents many formidable engineering problems.Mineral reclamation system design by theoretical formulas is almost impossible because solids composition, ie. concentration, velocity, moisture content, solid size, etc. can only be controlled within a broad pumping range.Traditionally this has restricted pumping to relatively dilute slurries whereas it is usually preferred, because of economic considerations to reclaim as high a concentration as possible.At Toyo/De-Velde Corp. we recognized these pumping limitations and began to develop and manufacture a range of standard and auxiliary equipment that would exceed these technical restrictions.MATERIAL RECLAMATION & PIPELINE INJECTIONTo minimize fluid usage and increase material reclamation efficiency we designed a submersible dredge mixing pump that uses most of its energy to pick up material from rest, mix it with fluid into a highly concentrated slurry then push it firmly into a pipeline.Where material is too compacted to be mined by the standard submersible mixer pump, auxiliary high torque self contained submersible excavators can be fitted around the periphery of the mixer pump. This is to facilitate excavation and break up of the compacted material into a slurry.High flexibility of this system can be achieved by combining the many equipment variations available into the most efficient format to fit individual site requirements.Whatever combination of equipment is selected, torque is nullified by counter rotating excavators against each other. This increases effective excavator/material bite torque but also allows mixer/excavator rig suspension by cable for deep water material recovery."

Jan 1, 1985

By H. Wilhelm, W. I. van Drunick

The Anglogold Ashanti (AGA) Navachab single stage SAG mill has provided an excellent setting for incremental optimization. Over the past decades, several interventions have resulted in marked improvements in specific performance; including steel ball scat removal, re-design of the mill lifters, replacement the pebble crusher and cyclone cluster, as well as the use of a vibrating screen in place of a discharge trommel. Recent initiatives now include an operating fine DMS circuit, studies on pre-crushing of the ROM feed and also fine-screening as an alternative to hydrocyclone classification. The current optimized state of the Navachab mill allows it to operate at approximately 20% higher efficiency when compared to mills of similar shell dimensions in gold mining, treating similar ore. This paper describes the systematic improvement of the SAG circuit to its current state.

Jan 1, 2012

By Pierre Gy

"Abstract - This paper deals with industrial complexes such as: (1) a mine producing metal-bearing ore and a furnace(s)/converter(s) where the ore is melted into metal, either directly, or after a mineralurgical concentration; and (2) quarries producing the raw materials required for the manufacturing of cement and the kilns to which they are fed.Each mine or quarry operation results from the exploitation of a mineral deposit. This deposit is never homogeneous. The raw materials which are extracted from the mine/quarry can never be safely fed to a "process" such as a cement kiln or a metal smelter, because the devices involved lack the flexibility required to absorb a very inhomogeneous feed. Furnaces and kilns are known to be very sensitive, sometimes dangerously so, with regard to deviations from a certain ideal feed composition.The purpose of this paper is to present the conditions required to optimize the operation of such a complex, so as to maximize the production, the quality of the product, as well as the profit generated. Two key operations are involved: sampling (to know accurately the materials being dealt with) and bed-blending (to achieve the desired degree of homogeneity). The theories of sampling and bedblending have been developed by the author and presented in various books (Gy, 1992, 1998)."

Jan 1, 1998

By Rainer Süss

An investigation was carried out by Mintek to investigate the influence of a range of alloying additions (vanadium, cobalt, zirconium, antimony and germanium) on the formability and hardenability of alloys with gold content >90 wt%. This paper reports on the hardening mechanisms that can be utilised to increase the hardness of gold (>90 wt% Au) by conventional alloying, as well as the hardening effect obtained by alloying with specific elements. Preparation methods for the alloys are described, which include the steps of melting, annealing, quenching, cold working and age hardening. Focus is given specifically on alloys that were developed at Mintek with a gold content >90 wt%, which are not only harder, but exhibit good resistance to tarnishing and corrosion.

Oct 1, 2003

By T. Macpherson

Drawing on past research experience with sprayable polymer mine support agents (TSLs), Spray On Plastics Ltd. has developed a TSL ground support system called RockWeb. Using a relatively new polyurea polymer technology, RockWeb has been engineered to solve problems encountered underground with polyurethane liners by incorporating rapid curing, moisture insensitivity and superior physical performance. RockWeb possesses a unique, patented ability to be sprayed in a ?cobweb? like consistency allowing the applicator to span fissures in the rock, ensuring no initial defects in the liner, and maintaining design thickness over highly irregular surfaces. This ability, coupled with the high strength and elasticity of polyurea, allows RockWeb to mitigate rock movement through yielding, while maintaining intimate surface confinement. RockWeb provides reduction in logistics through the transport of 1/25 of the material quantities required for shotcrete, rapid deployment rates of as little as 30 minutes per round, and immediate return to the work area. This paper will discuss the technology and advantages of RockWeb as well as opportunities for overall mining cycle cost reduction. The safety benefits, as well as health and environmental considerations regarding application of isocyanate-based liners will also be discussed.

May 1, 2009

By L. Xia, B. Hart, K. Douglas

In the flotation of Rare Earth Element (REE) bearing minerals, oxalic acid is reportedly acting both as a depressant and pH modifier. Testing has established the significance of oxalic acid in the flotation process however its specific role in either the recovery or selectivity of REE over their gangue minerals is not well understood. Pulp pH reduction trials with alternative acids have not shown the same effect on the REE mineral recovery or the depression of gangue phases. This work examines the effect of oxalic acid on the surface of gangue minerals (quartz and carbonates (dolomite and calcite)) in a series of conditioning tests. Gangue surface analyses by TOF-SIMS indicate that oxalic acid inhibits the transfer of secondary ions generated during the conditioning process from one mineral phase to another. In this regard, the oxalate anion acts to fix ions in solution through chelation, limiting their participation in surface adsorption.

Jan 1, 2014

By T. G. Joseph, M. Welz

ABSTRACT: Joseph (2002) introduced passive seismic monitoring to measure mining equipment performance. This paper evaluates the potential of passive seismic monitoring to correlate mining equipment operation with oil sands surface response, with a mining hauler as the seismic source. When applied to moving haulers, this action–reaction approach is complex. Vibrations from on-board equipment, such as pumps and tires, dirty the signal with noise. To facilitate any correlation, the signal must be cleaned up. Existing geophysical analytical techniques were manipulated to evaluate the noise problem and to filter sufficiently to permit an evaluation of whether a mining equipment action–ground response relationships in fact discernable.

Jan 1, 2011

By Clifford R. Stanley

"Abstract - Reproducible analyses of representative samples for elements affected by the ‘nugget effect’ is vital in mineral exploration and reserve estimation. Unfortunately, a priori knowledge of what size of sample is representative from a mineral deposit or its dispersion train is commonly unavailable. Use of the simple ‘equant grain model’ and the NUGGET computer program facilitates determination of the sampling parameters that will produce appropriate samples for chemical analysis. Based on Poisson statistics, NUGGET can be used to determine: (1) the ‘effective grain size’ of nuggets in a suite of samples, (2) the level of representativity (precision) that samples with specific nugget grain sizes will exhibit, and (3) the sample size required to obtain a specific level of sample representativity. The program determines these sampling parameters for any element in any mineral, including solid solution minerals (e.g., Au, electrum, Pt-Fe alloy, diamond), and allows assumption of a variety of grain shapes (e.g., ellipsoids, cylinders, parallelepipeds, etc.). Furthermore, it outputs the effective number of nuggets expected in a sample of given size and the percentile confidence bounds on any element concentration affected by the nugget effect.Results from the software allow determination of effective sampling and analysis strategies that minimize the nugget effect in geochemical analysis/assaying used in mineral exploration and reserve estimation. This will not only improve confidence in the resulting exploration results or reserve estimate, but will facilitate estimation of the error associated with any subsequent interpretation or reserve figure."

Jan 1, 1998

By C. Sideco

"Concentrate drying at the Sullivan Concentrator goes back to 1937 when the original coal-fired dryer was put into operation. This was a second hand 8' dia. x 56' long Struthers-Wells rotary dryer that came from the phosphate plant in Warfield, B.C.In 1962, replacement of the old dryer was seriously considered. The shell and the auxiliary drive mechanism were badly worn and needed replacing. In April 1963, the new 8' dia. x 65' long fuel oil-fired Struthers-Wells dryer went in operation at an installed cost of $174,000.In 1965, it was apparent that a major rebuilding of the dust collecting system would have to be done. A study was carried out and a Ducon Dynamic Gas Scrubber was installed. The system went in operation in November 1966 and has fully met expectations.In the same year, the zinc dryer was converted from fuel oil to natural gas. The conversion has resulted in savings in fuel cost of 12 to 15%.Frame No. 1Zinc Dryer PerformanceDryer Make - Struthers-WellsDryer Size 3/4 8' dia. x 65' long Drum Drive - 100 HPSpeed of Rotation - 5 RPMFeed Rate - 50-65 TPHFeed Moisture - 10-12%Discharge Moisture - 4-6%Dryer Inlet Temperature - 1600-1800°F Dryer Outlet Temperature - 200-250°F Stack Gas Volume - 25,000-40,000 CFNDust Collecting Efficiency - 99.75-99.98% Duet Loss in Stack - 50-300 lbs./day"

Jan 1, 1972

By Daniel Gendron, Luc Morin

"Concentrate sampling is a growing concern in the world's mining and smelting industry. The main modes of transportation for concentrate to the smelter are by truck or rail car in a bulk form, thereby limiting access to sample extraction equipment. In many cases, concentrate is shipped to a smelter by several suppliers therefore requiring individual manipulation of different customer samples in a safe and reliable manner. The Heath & Sherwood Bulk Product Sampler offers this feature as well as an economical and effortless way of obtaining samples in rail cars or truck boxes.In 1994, Noranda Metallurgie in Rouyn-Noranda, Québec purchased a self contained Bulk Product Sampler to extract samples directly from inside rail cars before unloading the concentrate. After testing and comparing the results with the conventional sampling method, the bulk product sampler proved to be a practical and advantageous solution for concentrate sampling both for the customer and smelter. Since its installation at the Horne smelter in Rouyn-Noranda, the Bulk Product Sampler has been steadily used on rail cars which contain concentrates from around the world."

Jan 1, 1996

By J. A. Drozdiak, A. Bamber

In this paper we examine, through pilot-scale testing, the possibility of operating a circuit comprised of two stages of HPGR comminution, followed by grinding through a horizontal stirred mill. In order to assess whether the novel circuit design could achieve the reduced energy requirements indicated in the literature, two more-established circuits, a cone crusher / ball mill and an HPGR / ball mill, were examined using a combination of testing and flowsheet simulation. The results showed that, based solely on the specific energy requirements for comminution, the HPGR / stirred mill circuit achieved a reduction of 9.2% and 16.7% over the HPGR / ball mill and cone crusher / ball mill circuits, respectively.

Jan 1, 2012

By J. H. Pateson, D. C. Comrie, D. J. Ritcey

"Geopolymers are inorganic semi-amorphous three dimensional silico-aluminates of the poly(sialate) type (-Si-O-Al-0-) or of the poly(sialate-siloxo) type (-Si-O-Al-O-Si-0-). Polycondensation occurs at low temperatures with geopolymers being stable up to 12oo0 c. Research, development and application technology pertaining to geopolymers is being undertaken jointly with Dr. Joseph Davidovits of The Institute for Applied Archaeological Sciences of Florida, U.S.A. This joint focused upon the chemical Barry University in Miami Shores, research and development program has stabilization and solidification of various waste products through geopolymerization. Of particular interest is the geopolymerization of mine wastes including tailings and waste rock derived from the processing of base metals, precious metals, potash, coal and uranium deposits.INTRODUCTIOND. Comrie Consulting Ltd., in cooperation and technical liaison with CANMET, Ottawa has been testing the application of geopolymers to mining wastes. Corporate efforts to date have concentrated upon reactive acid tailings, principally from the abandoned Kam-Kotia Mine site, and dewatered paint waste sludges. Test work conducted to date has successfully yielded geopolymer treated materials and wastes with increased chemical and structural stability. Wastes containing heavy metals, cyanides, arsenic and sulphur dioxide have been successfully geopolymerized."

Jan 1, 1988

By B. Loveday, G. W. Delaney, S. Cummins

"Applying DEM to prediction of tumbling mill performance is challenging because several different modes of breakage are active in the process. As our knowledge of breakage and computational capacity improve, it is worth revisiting previous simulation tasks which did not produce a satisfactorily realistic description of a measured process. At SAG 2006, we reported the simulated and measured outcomes of treating a well characterised ore in a 1.2 m diameter mill. This well instrumented, pilot scale mill at the University of KwaZulu-Natal has been combined with some new approaches to ore testing to allow different modes of breakage to be tested. The mill design allows the rate of generation of fine material to be measured in close to real time for autogenous and SAG mill charges. The updated simulation model estimates mass loss with particle evolution and embeds the cumulative damage and breakage.The simulated results are compared with the measured results. Issues such as relating modelling inputs to particle breakage characterisation data and the accuracy of the predictions of the models are discussed."

Jan 1, 2012

By Christopher McElman

Real-time mine management solutions have evolved over time from closed, proprietary solutions, to a "system of systems" that may include a wide variety of off-the-shelf components and technologies. Modular Mining Systems has embraced open standards for their NextGen products to bridge the technology gaps between these systems. However, the remaining logical gaps must be overcome, in order to achieve truly seamless integration between discrete systems. When dealing with volatile real-time management problems, the effectiveness of business process modeling and middle-ware can break down. Scientific principles of military command and control applied to mining domain help to achieve better alignment and reach the highest level of integration. The combination of open standards and off-the-shelf hardware and software with a deliberately structured command-and-control approach provides a clear evolutionary path from ad-hoc connected systems towards real-time management of a seamlessly integrated digital mine.

Oct 1, 2009

By Andrew D. Lapworth

The use of geological and grade models has been standard practice in mine design for many years now, with a wide range of software available to create and analyze the models. Although geotechnical parameters are also of vital importance for mine planning, there has been very little in the way of commercially available systems for integrating geotechnical data into the mine planning and design process. Sirovision is a new technology based on digital photography for automated, safe and accurate 3D mapping of geological and geotechnical features in rock faces. Datamine has integrated this capability into its product range so that Sirovision becomes an integral part of day-to-day face mapping, mine geology and geological / geotechnical modeling in both open pit and underground mines. This results in improved fragmentation for loading, hauling and processing, and for open pits local geotechnical conditions can be taken into account to improve slope design and control. This paper describes some of the ways that geotechnical modeling can be used to create more refined and cost effective mine designs and then discusses the role of Sirovision in enabling the raw data required for such modeling to be collected quickly, safely and reliably.

May 1, 2007

By Gary Walters, Thomas Gonzales, David George, William Davenport, Andreas Siegmund, Suping Yao, Shijie Wang

The previous survey of world copper smelters was in 2016 (Copper, 2016). The copper smelting industry has grown and improved considerably since then, including continuing growth in China and modernization in Japan (Extraction, 2018). Outotec flash smelting and Outotec flash smelting/Kennecott - Outotec flash converting continue to be adopted while newer processes continue to be adopted in China. In addition, some of the world's original flash furnaces have been completely rebuilt (Extraction, 2018). This paper provides recent industrial production data and discusses these new developments. INTRODUCTION A world copper survey was redone in 2016 after a thirteen year lag since 2003. Some of the notable changes were the significant increases in production particularly from China. Since then, several smelters have gone through modernization processes and decommissioning of older technologies. This paper will review the notable changes since the last publication at Cu2016. In the last paper, Copper Smelting: 2016 World Copper Smelter Data, the author gave an audible sigh after observing that copper smelter sites as well as new and notable smelters have been spreading like wildfire in China since 2003. Indeed, seeing is believing. Figure 1 shows the Ningde Copper Smelter (double flashing, 400,000 MT Cu/Year capacity) that started up producing copper in 2018; Figure 2 shows the Nanguo Copper Smelter that is under construction with 300,000 MT Cu/Year capacity (first phase, side blown smelting and continuous top blown converting). We should not only admire the Chinese copper industry’s significant technological developments, but also the copper price support that it has provided throughout this century.

Jan 1, 2019

By R. Harris

The vacuum thermal route for magnesium production today accounts for roughly 80% of the global production of magnesium despite significant investment in the competing electrolytic technologies, This is up from 30% of the global production 10 years ago and is all the more significant because global magnesium production has more than doubled in the same time, A review of the sophisticated anhydrous magnesium chloride production technologies provides some explanation for this sea change in technology usage, However, an examination of the economic factors provides compelling reasons, The present review outlines some of the salient strengths and weaknesses of the competing technologies, It also offers suggestion as to where future R and D and economic effort needs to be vested to improve the sustainability of the world magnesium market in terms of its value and impact.

Jan 1, 2006

By P. B. Marchant

"Based on laboratory and pilot scale continuous biooxidation of complex sulphide concentrates, commercial processing design and scaleup considerations are discussed. Capital and operating cost estimates for commercial biohydrometallurgical operations are summarized and potential applications of biotechnology are discussed. Biooxidation as an oxidative pretreatment alternative to enhance precious metals extraction from refractory sulphide concentrates in stirred tank reactors has received considerable attention recently due mainly to advances in the practical applicability of the process. Biooxidation of sulphides is certainly not a new process, however, application and control in large scale hydrometallurgical operations to treat refractory sulphides remains conceptual and the limited data available is restricted to relatively small laboratory and pilot scale operations. It is the intent of this paper to indicate scaleup and plant scale process design considerations for commercial bioleach circuits, based on recent operating experiences with laboratory and pilot scale continuous bioleach systems. An indication of the expected range of applications will be presented parameters for optimization will be discussed."

Jan 1, 1986

By M. Moghadami

Design and construction of underground openings are associated with many uncertainties with regard to input data. In the construction process of underground openings various levels of risks exist and these affect the safety and profitability of the project. The development of underground openings can be broadly categorized into three major phases of data collection, design, and construction. A significant level of uncertainty is associated with some of the key parameters involved in the aforementioned development phases. Moreover, it is very difficult to evaluate and quantify the effects of uncertainties on the underground project construction process. Additionally, the interactions between important risk elements are typically not well understood. The intention of this study is to develop a general risk model for underground opening projects located in soils and weak rock masses. The goal of the research is to identify and quantify important geotechnical risk elements. Moreover, a weighting procedure will be proposed for the identified risk elements. Finally, all important risk elements will be assembled into a general model with emphasis on geotechnical parameters. The final objective of this study is to apply the proposed model to a real underground project scenario and verify it for actual field conditions. The proposed model, once calibrated properly, will provide a useful support tool for the decision making process.

Aug 1, 2013

By A. C. Drost

The mining industry has been put under closer scrutiny in recent years, which has led to the adoption of a plethora of initiatives in countries around the world and by international organizations, some voluntary and others mandatory, governing economic, ethical, social and environmental practices of this industry. In order to plan appropriately, secure project financing, build value and manage risks, it is imperative to identify and understand the application of this new and evolving regime, which can be described under the general label of corporate social responsibility (?CSR?) law, and to incorporate compliance policies into the day-to-day operations of mining companies. Our paper and presentation will describe this new legal framework, which includes both ?soft? law and ?hard? law adopted at the international and domestic level that governs the actions of mining companies, particularly when operating in developing countries. While the notions of hard and soft law may seem abstract and grounded in legal theory, this paper shall demonstrate how these concepts concretely apply to companies in general, and to mining companies in particular. An analysis of the recent case law in this area as well as examples of corporate ?best practices? will illustrate the application of this body of law. As will be demonstrated through the case law, non-compliance of CSR law (both ?soft? law and ?hard? law) can lead to economic penalties, difficulties in accessing capital, loss of social licenses and even the withdrawal of permits and concessions. This confirms that now more than ever, ethics and sustainable practices in mining are fundamental to building a successful business model.

Aug 1, 2013