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By R. D. Clark, Heinz Althoff

"The advantages and disadvantages of a mobile crushing plant with a belt conveyor system compared to a stationary crushing plant with haulage by heavy trucks are described. The capital expenditure and operational expenses are compared and the individual cost factors are explained.Every open-pit mine or quarry, however, is different and has to be assessed and analyzed individually in order to find the optimum and most economical solution. Due to the high truck haulage costs, many open-pit mines tend to the more economical solution with mobile crushing plants and continuous belt conveyor operation. IntroductionFor the material haulage within an open-pit mine the heavy truck is the most flexible means of transportation. However, due to the high fuel consumption, wear and labour costs, it is also the most expensive one. Therefore, many open-pit mines are looking for alternative solutions for the material transport A mobile belt conveyor system is most likely to meet the requirements because it is efficient and economical with regard to the power consumption. The material , however, has to be crushed at the mining face to lumps which are suitable for conveyor operation. For this purpose a mobile crushing plant is required.In some open-pit mines the crusher is also used to crush the material to lumps of smaller particle sizes in order to save crushing costs in the preparation plant.Although a cost comparison between a system with stationary crusher and truck haulage and a system with mobile crusher and belt conveyors favours in most cases the belt conveyor system, up till now only a few open-pit mines and quarries benefit world-wide from the advantages of the mobile crushing plant with continuous belt conveyor operation."

Jan 1, 1986

By G. Barbery, P. Dauphin

"In order to obtain reproducible and reproducible results in batch flotation, researchers have tried various approaches, from normalized testing, to modifying existing cells, and even designing new machines. The paper reviews the basic concepts that must be fulfilled in a laboratory flotation machine, and present the FLOTOMATEC design, which results from five years of testing and development. In addition to providing accurate measurements of air flowrate, power consumption, agitation speed, the cell eliminates most operator induced errors. Results of experiments comparing FLOTOMATEC to a conventional cell, as well as reproducibility tests are given. Introduction The use of batch flotation machines in mineral processing research and development is very common. These machines have been used for many years without almost any change in their design, instrumentation or automation. Various authors since Raffinot (1960) have criticized the available designs, especially with respect to the large errors that are introduced by the manual mode of operation. Barbery et al. (1986) have presented a review of the problems involved in laboratory testing in flotation research.Batch laboratory machines should have the following characteristics:"

Jan 1, 1989

By Randy Billing, J. Fraser Wilson

"IntroductionThe job of designing and implementing effective environmental management sounds like what one executive, assuming responsibility for a very sick organization with lots of potential described as, ""an insurmountable opportunity"".Effective environmental management is an opportunity, no doubt. Its an unusual, if not unique opportunity. Insurmountable? Maybe not! Indeed, in the authors' experience, the keys to unlocking this opportunity are not in new or complicated technicalities; they are in the existing strengths and successful experience that one has in managing other complex and exacting management issues.To begin, it is necessary to understand what these issues of sustainable development mean to business. What is the nature of this opportunity? What makes it look unsurmountable?New Games: New RulesLawyers have described some of the new rules companies are facing and there is a new game being played; a game characterized by unique challenges.Take two, for example: • The ecological problems to be faced are Mother Nature's business, the political solutions required are our business. This combination of natural problems and political solutions requires the development of new management mechanisms, to bridge the gaps among us, as individuals, as professions, as interest groups and so on; indeed, even as countries;• and gaps there are : about as many gaps as the people involved : many of them with new and changing expectations, often mutually exclusive and not negotiable.The challenge of these relationships and communications among so many different interests is one of the keys to effective environmental management.Like any game, this one has rules and they are new, too. These rules are evident not just in new legislation - tough legislation with draconian penalties; they are also evident in new and exacting business policies, value driven and just as unforgiving of poor performance. Senior management of many companies are speaking about the role of enlightened corporate policies and how important it is for everyone involved that these policies drive and reflect business practices. Absence of day to- day behaviour which evidences the words in action, the policy on the wall of a corporate office or published in an Annual Report is first evidence for the prosecution , not the defence.The challenge of practical policies is another key to effective environmental management.This is a new game, with new rules: the challenge of change."

Jan 1, 1991

By Jonathan Peck, Jim Gray

"With the implementation of more advanced monitoring, control and locating systems in surface mines, there is an ever increasing need for their mine-wide integration toward achieving over-all optimization. AQUILA Mining Systems Ltd. is developing the basis for a comprehensive real-time monitoring, control and information system called the Total Mining System or TMS. This system is being designed to address both current and future needs of open pit mines toward improving productivity and minimizing costs, through better two-way information flow between each component in the operation. At a basic level, feedback from equipment and process monitoring will enable decision making to be based on quantitative, on-demand information, thus permitting proactive rather than reactive planning. Dynamic planning would be a valuable tool as market conditions fluctuate, equipment fleets age and variations in the grade, quality, geometry and hardness of the mined material all contribute to either changing production targets or levels of achievable performance. Such a capability could be implemented within the next two years.At a higher level, and within five years, autonomous operation and/or real-time supervisory control of mobile and stationary equipment in open pit mines will be achieved. A discussion is provided in regard to the development and implementation of an autonomous haultruck and blasthole drill, to demonstrate the need for such a system.This paper outlines a preliminary program for the design, development and implementation of this system, primarily in relation to high-level communications and its role in the future automation of open pit mobile equipment."

Jan 1, 1995

By H. Asgari, A. G. Odeshi, J. A. Szpunar

In the present study, the dynamic response of AZ and AE cast magnesium alloys to shock loading, are compared for strain rates ranging between 900 and 1200 s-1. Texture measurements showed that after shock loading, the (00.2) basal texture component of both alloys was strengthened. However, the strengthening magnitude was higher for AE samples. Also, it was observed that the twinning fraction decreased in both alloys with increase in the amount of alloying elements. In addition, cracks are formed at the interface between matrix and second phase particles in the AZ alloys. However, crack nucleation and fracture in AE alloys occurred at the sites where twins accumulated. Furthermore, analysis of the dynamic mechanical behaviors showed that the ductility of AE grade is higher than that of AZ alloy for all strain rates used in this research. This difference was explained by differences in deformation mechanisms of these alloys.

Jan 1, 2014

By Kr. N. Karparov

Measurements made with high precision GPS landmarks and geotechnical radar Reutech MSR- 300 associated with the observed movements in the north face of Assarel Mine, where on a horizontal distance of 50 m, 2 groups of landmarks indicated different deformation behavior. Measurements are made in order to confirm the applicability of the radar system in regions of complex geotechnical conditions. The standard deviation of each landmark is used as an accuracy standard between the separate measurements of the deformation vectors made by the high-precision GPS system for each landmark. A very good correlation between the displacement vectors can be seen based on the measurements made with the high-precision GPS system and the measurements made by the radar system MSR-300. Geological, engineering geological and hydro-geological conditions of the area of concern are discussed in this paper. The measured deformations and the FLAC/SLOPE analysis show similar results. In the paper is discussed their local character and their sensitivity to other geotechnical and hydro geological conditions.

Aug 1, 2013

By G. Sperlins

"IntroductionBrenda Mines Ltd. is a low-grade open-pit mining and milling operation located near Peachland, B.C. Brought into production in late 1969, the plant treats an average of 30,000 tons per day of an ore that contains 0.130% copper and 0.030% molybdenum.The operation is divided into six areas of responsibility, namely the mine, mill, plant, accounting, industrial relations and purchasing /stores departments.The purchasing and warehousing area handled in excess of 11,000 items valued at $31,000,000 in 198J. Over and above this, the warehousing area issued in excess of 74,000 line items valued at $15,000,000 during that same period.Materials Management- DefinitionWhat is meant by the term ""Materials Management""? Reference to the dictionary will reveal that a material is ""that of which anything is composed or may be constructed; the tools, instruments, implements', etc. for doing something"". Management is defined as ""the act, or manner of managing; the skillful use of means to accomplish a purpose"". Presumably combining these words defines materials management.Of greater importance are the materials managers who will carry out the function. At Brenda Mines Ltd., all employees and suppliers contribute to the materials management function. Each has a specialized knowledge of the materials used in his field. Each has a different view concerning the use and description of the same material. The key is to focus this knowledge so as to make the materials management system useful to everyone."

Jan 1, 1982

By Bian Xue, Wu Wenyuan

High quality, mono-dispersed, hollow CeO2 microspheres with high surface area were produced by a spray pyrolysis method at 700oC. CeCl3 was used as the raw material of the process rather than Ce(NO3)3 because the latter is relatively difficult to obtain in industrial quantities. X-ray diffraction and electron microscopy results confirm the high quality synthesis of hollow CeO2 microspheres with narrow size distribution, good mono-disperse, and good reproducibility. The process of the formation of mono-dispersive CeO2 microspheres was investigated by chemical dynamics and a possible mechanism is proposed. This simple method for synthesis of CeO2 microspheres is easily scaled up to fabricate other metal oxide nanostructured materials at industrial scale.

Jan 1, 2014

By H. Sakurai, M. Kato, F. Tanaka

The Mitsubishi Continuous Copper Smelting/Converting Process employs an electric furnace (CL- furnace) for settling the slag/matte mixture formed in the smelting furnace. The conditions in the CL- furnace change its settling efficiency, resulting in high variability of copper losses in slag. Modifications of the operation and maintenance procedures for the CL-furnace have significantly and sustainably reduced the copper losses in Gresik smelter to below 0.7%. A series of flow patterns evaluation in the CL-furnace demonstrated how the chemical reactions and settling conditions of the CL-furnace has been improved by the new operating procedures. Settling mechanisms for the matte droplets in the CL-furnace is also discussed using image analysis of solidified slag. INTRODUCTION The Mitsubishi Continuous Copper Smelting/Converting Process employs an electric furnace (CL- furnace) for settling the slag/matte mixture formed in the smelting furnace. Since the top-blowing in the S- furnace agitates the molten bath strongly, matte droplets are dispersed over the slag phase when melts flow out of the S-furnace. Thus, the CL-furnace has an important role to settle and recover matte droplets efficiently. Since many papers have ascribed major part of copper losses to matte droplets suspended in slag (Tanaka 2007; Genevski et al., 2008; Starodub et al., 2016), flow patterns of slag in the CL-furnace can affect greatly on the profitability of smelters which have adopted the Mitsubishi process. PROCESS DESCRIPTION Figure 1 illustrates the Mitsubishi process schematically. The Mitsubishi process is the only system for continuous production of blister copper from copper concentrates and consists of 3 furnaces connected by enclosed launders those ensure the minimum emission of fugitives. In a smelting furnace (S-furnace) copper concentrates are fed with flux, oxygen-enriched air to form a mixture of slag and matte which cascades down to a slag-cleaning furnace (CL-furnace). The CL-furnace settle matte droplets in the mixture on the crucible from which matte is siphoned to a converting furnace (C-furnace), while discharging the cleaned slag (CL-slag). The C-furnace converts matte to blister copper by the top-blowing of oxygen- enriched air.

Jan 1, 2019

By A. McLean, X. Men

"With high quality sulphide ores diminishing, nickel production from low-grade oxide ores becomes increasingly important and a major concern is the high sulphur level in the resultant ferro-alloy. So, desulphurization of the ferronickel becomes an important consideration. Red mud is a waste product of alumina industry and causes adverse effects on environment. In the present study, experiments were conducted to determine feasibility of using red mud as a major ingredient of refining fluxes for ferronickel desulphurization. In view of their influence on slag-metal separation, contact angle measurements between ferronickel alloy and molten slag made from red mud were also determined. INTRODUCTIONNickel is a very important metal that finds a variety of applications including consumer products, building, automotive and electronics. There are two kinds of ores containing nickel, namely oxide and sulphide ores. Anthony and Flett [1] reported that about 55% of the world’s nickel production originates from sulphide ores while the balance of new nickel is derived from oxide ores. However, oxide ores count for about 70% of the worldwide reserves. Apparently, oxide ores will play a significant role in the production of nickel in the future. Most of nickel produced using oxide ores is from pyrometallurgical processes namely ferronickel smelting or matte smelting. So, we can draw such a conclusion that using nickel oxide ores to produce ferronickel will become more and more important .Before used to make stainless steel or other materials, the ferronickel need pretreatment to remove impurities especially sulphur and phosphorus that will cause negative influence on the properties of steel product. Red mud is a by-product during alumina production. Usually, about 1 to 1.5 tons of red mud will be produced when we get 1 ton of alumina. About 90 million tones of red mud are produced every year in the world [2].Red mud is deemed as a toxic industrial waste which needs treatment before discharge because of alkalinity and chemical and mineralogical properties. Until now, the main means to deal with red mud are to store it in impoundments or dump it in the sea depending on local environment. Nowadays, how to recycle red mud has become a pretty hot topic around the world. The last 40 years have witnessed a lot of patent applications concerning the ways of red mud utilization. However, a little amount of red mud is consumed until now due to the limitations of recycling red mud."

Jan 1, 2012

By Dallas Bienhoff

Boeing Study Team Participants Andrew Daga & Associates American Aerospace Advisors Hamilton Sundstrand Harris Honeywell ILC Dover Lunar Transportation Systems Oceaneering Orion Propulsion SICSA Thin Red Line USA LSSCA BAA Topic 2: MFHE Definition Minimum Functionality Habitation Element Deployable Habitat DHE Update The Path to Growth

May 1, 2013

By Xueyi Guo

The total production of nonferrous metals in China is 31.35 million tons in 2010, which ranks first in the world for the past ten years. Large quantities of solid wastes including slag, residue, ash, and dust are produced every year in the production of nonferrous metals. These secondary resources are renewable, not only contain abundant valuable metals which can be recycled by metallurgical processing, but also could eliminate the pollution to the environment. In this paper, the status quo of the main nonferrous metals recycling in metallurgical industries in China was summarized, and the future development of waste processing and resource recycling was prospected.

Jan 1, 2011

By E. Sigal

Overview ?Intrinsik has completed several wide area HHRA and ERA studies of mining and smelting communities ?Several ?Lessons Learned? ?Key areas related to: ?Study Design ?Data Quality ?Bioaccessibility ?Speciation ?Weight-of-Evidence Approaches ?Advances in Ecological Risk Assessment Techniques

May 1, 2009

By A. Saki, P. Gebski, W. Ying

Industrial smelting furnaces are subjected to significant structural changes and deterioration caused by the conditions under which they operate. The current methods for the structural assessment of furnaces include visual inspections, analysis of thermal data, acousto ultrasonic-echo (AU-E) of the refractory lining and surveying of the key structural elements. Acoustic Emission (AE) non-destructive testing (NDT) technique has proven its capabilities for continuous monitoring of industrial installations and structures. Recently, Hatch Ltd. has been successful in applying acoustic emission for monitoring furnace tapblocks, and expanding the scope of the acoustic emission monitoring to the structural integrity of the entire furnace. The capability of detecting emissions related to the fracture development in the furnace shell, movement of the refractory, electrode arcing, combined with efficient source location algorithms makes an acoustic emission system a comprehensive tool for the real-time furnace integrity monitoring. In this paper the concept of such state of the art system for structural integrity assessment is presented. The initial results of the acoustic emission monitoring together with data analysis techniques are discussed.

Jan 1, 2011

By M. Reda

Because of the adverse environmental effect of Chromate, Molybdate ions had been investigated as replacement for Chromate and the results had shown not to be encouraging. Film deposited from peroxopolymolybdate (from reaction of Molybdenum meta, with excess Hydrogen Peroxide), are more robust than that deposited from molybdate solutions. This was shown to be due to higher fraction of Mo (IV) and Mo (V) that form from Mo (VI) in the peroxopolymolybdate deposited film than the film deposited from Molybdate solutions. The peroxopolymolybdate film contains 40% un-hydrated molybdic acid, tetraperoxodimolybdate and tetra peroxo tetra molybdate. The protective properties of peroxopolymolybdate were shown to be due to the effectiveness of the un-hydrated molybdic acid.

Jan 1, 2010

By W. Evans, T. Steis

"Sulphide ores under certain circumstances will react with explosives to generate an autocatalytic chemical reaction. This reaction is exothermic and results in the production of large volumes of poisonous gases and creates an unsafe, unstable condition with the possibility of a low energy deflagration or even a detonation of the loaded hole. This paper outlines the conditions that need to exist for such a reaction to take place and the precautions necessary to minimize or eliminate the problem in areas of reactive ore. A special case study involving a northern Ontario mine will be detailed.IntroductionOne of North America's leading underground gold producer's processes over 6500 tonnes of ore per day from an orebody containing high concentrations of sulphides. After six years of problem free operation, the mine experienced two serious reactions in two months between the sulphides and AMEX II, the ammonium nitrate and fuel oil explosive it uses."

Jan 1, 1995

AGENDA ? Company Overview ? Industry Direction ? Technology to support maintenance ? data access, connectivity, process historian, downtime & production reporting. ? Case Studies Company Overview Corporate Offices Client Base ?16 consecutive years of growth & profitability ?#39 of Top 50 Control Companies (Worldwide) ?470 employees ?TSX: MTK Industry Direction Improved visibility into the business so they can: ? Reduce cost through better understanding of where costs are being incurred and making timely decisions. ? Optimize operations while leveraging existing assets. ? Have a single version of the ?truth? ? Deliver reliably to stakeholders on the demand for increased accountability (safety, environmental, regulatory performance etc?). ? Respond quicker to market conditions in order to out perform the competition ? Best in Class approach. Web is becoming the standard user interface.

Apr 1, 2005

By Jun Shan

The preparation of poly(N-isopropylacrylamide)-monolayer-protected clusters (PNIPAM-MPC) of gold nanoparticles was carried out in a homogeneous phase using three ways, in which three types of PNIPAM ligands were employed. The first type comprised of PNIPAMs with narrow molar mass distributions, synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and thus, bearing a dithiobenzoate at the chain end. These polymers were used directly to passivate the gold nanoparticles upon the Schiffrin reaction in a one-pot synthesis. The second type of ligands was derived from the first one through hydrazinolysis, and they therefore contained a thiol end group. The third type of ligands was PNIPAMs obtained through conventional radical polymerization, post-modified to contain thiol end groups. The PNIPAM-MPCs were characterized by high-resolution transmission electron microscopy, and by dynamic light scattering. The one-pot synthesis utilizing the ligands of the first type turned out to be a simple and facile method, compared with the other two ways, with which the size of the gold nanoparticles can be easily manipulated mainly by adjusting the molar ratios of PNIPAM / HAuCl4. PNIPAM is a more efficient ligand to stabilize the gold nanoparticles in water and in organic solvents than alkanethiols. The surface density of PNIPAM chains ranged from 1.8 to 3.6 chain/nm2, which is much lower than that typical for alkanethiols. The thickness of a PNIPAM monolayer bound to the gold core is somewhat larger than the size of the random coil of corresponding free PNIPAM in aqueous solution, which suggests that the conformation of a PNIPAM chain bound to the gold core is to extended.

Oct 1, 2003

By Mengsu Hu, Yuan Wang, Jonny Rutqvist

Material interfaces and typical boundary conditions are boundaries influencing the existence, uniqueness and stability of numerical solutions of water flow in heterogeneous media. The Numerical Manifold Method (NMM) with a two-cover-meshing system is an ideal method to handle boundaries, considering its flexibility with no need to adjust mathematical nodes onto boundaries, the meshing efficiency, and its integration precision. In this study, we derive and compare two new approaches for boundary constraints, i.e., a discontinuous approach with Lagrange multiplier and a continuous approach with jump function in the frame of NMM. In the discontinuous Lagrange multiplier method (LMM), Dirichlet boundaries or the material interfaces are regarded as discontinuities which are linked by Lagrange multipliers. In the continuous Jump function method (JFM), the material interfaces are regarded as inner interfaces, where the refraction law is realized by constructing jump terms with discontinuity of hydraulic gradient in its normal direction. Both the continuous and discontinuous approaches make full use of the aforementioned advantages of NMM and are established based on a clear physical meaning of water flow by our energy-work seepage model. The newly derived boundary-constraint approaches were coded into an NMM water flow model and tested for precision and efficiency on different simulation examples. We first tested both LMM and JFM for an idealized heterogeneous model, comparing the numerical results with analytical solutions. Then we tested both approaches with a heterogeneous model and compared the results of hydraulic head and specific discharge. We proved that both approaches are very suitable for material boundaries considering the accurate realization of the boundary constraints and the flexibility with no need for mesh-conforming.

Jan 1, 2015

By Michel Grenier, Robert Scott, Mahendra Gangal, Andrew Dasys

This research project which took place at Brunswick Mining and Smelting's Brunswick mine, was undertaken to assess the ability of new diesel engine technology to meet current and anticipated underground worker exposure limits to diesel exhaust contaminants. Concentrations of CO, CO2 NO, NO2 SO2 and respirable combustible dust (RCD) were measured in a remote mine area where a haulage truck was operating under simulated duty cycles. The 26 ton haulage truck was equipped with a 300 hp, electronically controlled engine. Fresh air was supplied to the area as per the MSHA certification document for this particular engine. Results showed that while the vehicle operated in a normal and realistic duty cycle, the concentrations of contaminants remained well below the ACGIH guidelines for the threshold limit values (TLV)for exposure. While operating at 630/0 of maximum horsepower (26 tons of ore in the dump), the time-weighted average exhaust gases concentrations (CO, CO2 NO, NO2 and SO2) never exceeded 150/0 of their respective TL Vs. ReD concentrations in this instance were measured at 0.59 mg/mJ or 39.30/0 of the exposure limit suggested by the Canadian ad hoc Diesel Committee. The Air Quality Index was 1.55 or 520/0 of the maximum suggested value for exposure.

Jan 1, 1994