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"Since World War II, urban communities have expanded at an unprecedented rate. The industrial mineral industry supplies the sand, grave], limestone, crushed rock, cement, gyp-sum, etc. for urbanization. Most de-posits in use are close to or within communities. Pollution of water and air has become a matter of public concern. Waste disposal and the effects of noise and vibration are subjects of public debate. Need for the reclamation of land after operations such as strip mining is discussed in magazine articles and on TV pro-grams; i.e., the general public is educated in the unattractive features of mining.Legislation is on the books and being drafted to regulate mining operations and their side effects. To avoid over-regulation and restrictive legislation, it is necessary that the public be educated and legislators informed of problems peculiar to the mining industry. Our side of the story needs publicity."

Jan 1, 1968

By L. Shasko, M. Hurlbert

As climate change is increasingly perceived as a problem, and fossil fuel based power production options are increasingly limited through regulatory restrictions and public distaste, future options become constricted. Reflexivity and social learning elicited through qualitative and mixed research methods offer important insight into what future power production pathways might be. Given factors of cost, baseload requirements, and energy density, options such as nuclear may be increasingly accepted. This paper explores this literature and possible methods of pursuing the reluctant acceptance of nuclear energy.

Jan 1, 2020

By Brien A. Perry, Art Wiebert

"Many organizations which have implemented Total Quality Management (TQM) are finding that the process has either stalled or is not working so well as originally envisioned. This can be particularly evident in an engineering environment where the uniqueness of engineers and their particular culture has not been adequately considered. Winning the commitment of a highly educated group ojprojemnnJJ1s to the TQM concepts, which are often initially 5W2 as too simplistic poses special challenges.Successful TQM implementations are found among technical groups where employees have significant input into creating the new work culture, feel empowered to make changes and are well trained in teamwork. A coach who is knowledgeable in implementation problems can, when working closely with the technical teams, help them circumvent obstacles and guide them successfully through the difficult early phases. The remaining key ingredient for success is supportive management which leads the change and is both informed and appreciative of the accomplishment being made.This Paper is based on first-hand experience with common problems and results encountered in implementing TQM in an engineering environment. Described in the paper are ways of avoiding these problems through awareness of the unique nature of engineering groups, implementation planning, just-in-time training and coaching people in the TQM process. The paper concludes with a focus on the opportunities and results from a successful implementation. These opportunities and results include the benefits each engineer can realize through process thinking, empowerment and teamwork."

Jan 1, 1995

"Cambior now holds a 49% interest in the Valdez Creek Placer, having acquired American Barrick's 23.125% interest in May 1990. At the same time, the company assumed the management of the operation and received environmental permits to divert the river. Plans are underway to divert the Valdez River in order to continue mining the deposit upstream, and to construct a new, higher capacity wash plant (by 60%) closer to the operations. Mining operations, which were suspended in October 1989 pending higher gold prices, resumed in August 1990. The mine is expected to produce 10000 ounces of gold in 1990and more than 80 000 ounces in 1991.IntroductionThe Valdez Creek Placer is located in the Valdez Creek mining district of Alaska on the western flank of the Clearwater mountain range, about 150 miles northeast of Anchorage by air (Fig. I) . The mine is accessible by air or by road.The mine is situated at an elevation of about 3000 ft and is isolated from towns and villages. Consequently, the mine site contains the facilities necessary to house and feed 135 people at any given time. The Valdez Creek Placer has 159 employees, including 130hourly and 29 salaried employees. The hourly employees are divided into three rotating teams. The daily schedule consists of two shifts of 12 hours, and each team works 14 days followed by seven days off, resulting in a weekly rotation of teams.The salaried employees work normal hours for ten consecutive days followed by four days off. A weekly rotation ensures continuity of services and management.Gold was first discovered at Valdez Creek in 1903, when a team of four men led by Peter Monahan left the village of Valdez to explore the area up the Susitna River, to the east of Mount McKinley. They discovered gold at the mouth of a creek that they immediately named Valdez Creek, in honour of their native town. In 1904, they discovered the Tammany Channel to the right of Valdez Creek. This was the beginning of a long period of mining in the area which continued until the beginning of World War II .In 1980, the Denali Mining Co. was formed. Geophysical work and drilling carried out through 1980 and 1981 led to the discovery of Channel A, a second channel which is older than the Tammany Channel. In 1983, Denali Mining optioned its claims to Camindex to explore, develop and mine the Valdez Creek property. A joint venture agreement was signed among Camindex, Talcorp, BCP Alaska (Barrick), Sum Resources (Cambior), Norfran and WGM to form Valdez Creek Mining Co., Inc., and production began in 1984. Valdez Creek Mining Co., Inc. (VCMC) was subsequently restructured and in 1989 was held by the following three companies: Camindex Mines Ltd. - 51070; Cambior Inc. - 25.875%; and American Barrick - 23.125%.VCMC is managed by a committee of the partners. Decisions made by the committee are subject to a 70% majority vote. Cambior receives its share of production in kind, and contributes in the same proportion to the expenses of the joint venture (VCMC)."

Jan 1, 1990

WHAT IF? ?Mine closure and reclamation liabilities were fully funded -at all times from current mine revenues ?Unexpected & catastrophic events were insured ?Remediation costs could be capped ?Risk management was improved ?best practice and independent oversight ?Host communities?concerns were adequately addressed If this could be achieved within a cost-effective financial structure, this may be a solution to a complex issue for the mining industry

May 1, 2006

By T. H. Etsell, P. C. Holloway

The fly ash produced by oil sands operations in northern Alberta represents a large, high-grade, potential resource for vanadium production in Canada. After extensive batch testing at the University of Alberta, a conceptual process flowsheet for the recovery of vanadium from oil sands fly ash has been developed. The various unit operations for this process, including decarbonization, roasting, leaching, desilication, precipitation, salt recovery and byproduct recovery, are described. Processes for the recovery of molybdenum and ammonium chloride from waste streams from this process, are proposed, as are potential uses for the ash residue; these byproducts represent significant potential sources of secondary revenue while reducing the environmental impact from the process. A preliminary economic analysis for vanadium recovery from oil sands fly ash using this process is also included and several major economic factors influencing its commercialization are discussed.

Jan 1, 2004

Ion Exchange is finding a greater role in copper processing, and hydrometallurgy in general, both as a technique for removing impurities and as a means of adding value through the recovery of secondary metals. Both the gold and uranium industries use resin adsorption as a primary production technique. While hydrometallurgical processes predominantly rely on solvent extraction as the mainstay of copper recovery there are a number of projects, in particular polymetallic deposits, which are considering the use of resin recovery as an alternative or supplemental production technique. A number of applications have been developed and proven at commercial scale for the removal/control of impurities (iron, antimony and bismuth) from copper electrolytes. These are well documented ion exchange applications. Increasing metal values and scarcity of certain metals are focusing companies to look at secondary metals recovery rather than losing these often highly valuable metals to tails residues. Bleed streams are being seen as valuable opportunities to recover contained metals; iron, copper, nickel, cobalt, bismuth, antimony and rhenium are all metals being targeted for removal or recovery from process solutions, electrolytes and bleed streams. An overview of currently applied techniques as well as some developmental technologies for impurity removal and secondary metals recovery is presented to provide insight into the advantages and flexibility of ion exchange applications in metals processing.

Jan 1, 2007

"These guidelines, implemented in 2003, were recommended by the Diamond Exploration Best Practices Committee established by the Canadian Institute of Mining, Metallurgy and Petroleum. The guidelines are applicable to public companies and their consultants reporting diamond exploration results.“The guidelines are referenced in the Companion Policy of NI 43-101 with a statement that disclosure regarding the reporting of diamond exploration sampling results should conform to them.”Reporting GuidelinesThe following guidelines have been recommended by the Diamond Exploration Best Practices Committee established by the Canadian Institute of Mining, Metallurgy and Petroleum. These guidelines are applicable to public companies and their consultants reporting diamond exploration results.In respect of these guidelines, Diamond Exploration Results are results derived from the initial activities undertaken to investigate a diamond bearing prospect or deposit, to generate tonnage, grade and value estimates that cannot be classified as a Mineral Resource or Mineral Reserve. They do not address the earlier stage reporting of geophysical, geochemical or kimberlite indicator mineral results.Public reports of Diamond Exploration Results relating to mineralization not classified as Mineral Resource or Mineral Reserve must address the confidence limits of the result and contain sufficient information to allow a considered and balanced judgement of the significance of the results.The objective of these guidelines is to assist public companies and consultants in making appropriate disclosure of diamond exploration results by reporting in a manner which is:Uniform within the diamond exploration industry; Consistent with reporting from other industry sectors .Comprehensive .Unambiguous .The guidelines are not prescriptive. Materiality is the overriding principle that determines the information that should be disclosed. However, where a company or consultant deviates from the guidelines, the disclosure or technical report should state the extent to which the guidelines have not been followed, and the reasons for the deviation.The guidelines do not in any way replace jurisdictional reporting requirements (For example, the requirement for Canadian reporting issuers to comply with Canadian Securities Administrators National Instrument 43-101 by having technical disclosure endorsed by a Qualified Person as defined in that legislation)."

Jan 1, 2003

By S. Asano

Hydrometallurgical processes for treating copper sulfide concentrates have attracted considerable attention over thirty years and many processes have been developed. However there have been still problems in those processes because of difficulties of iron removal and high purity copper production with low operating cost. Although SX-EW is highly cost effective method, it is difficult to process the chalcopyrite. Sumitomo Metal Mining Co., Ltd. (SMM) conducted a review of hydrometallurgical copper concentrate processing and has successfully developed a novel process for the hydrometallurgical production of copper from copper concentrate. In this process, copper sulfide is leached by chlorine gas under atmospheric pressure. Most of hydro metallurgical processes can leach only some of chalcopyrite under atmospheric pressure then they need high pressure leaching facility like autoclave. In this process, copper in chalcopyrite can be leached completely by controlling oxidation reduction potential and chloride ion concentration. Cu(I) ion in leached liquor is separated from Fe(I!) ion by SX using TBP then pure copper powder is produced by electrowinning. Results in batch and continuous testworks and pilot plant tests at Niihama Research Laboratories are presented in this paper. Cu2007

Jan 1, 2007

By John C. Loretto

"Answers to some of the problems ofRecovery and Metallurgical AccountingIn Gold and Silver Hydrometallurgical PlantsThe start-up over the last few years of new hydrometallurgical plants for the recovery of gold and silver has brought to the surface again a number of problems. Most of the problems have existed for some time and they manifest themselves mainly in two ways. Firstly, the plant results do not agree with the Metallurgical Test work figures and secondly, the Metallurgical Accounting figures do not balance.The plant results not agreeing with testwork figures are mainly due to:a) The testwork samples were not representative of the eventual plantfeed;b) Misinterpretation or misunderstanding of testwork;c) Plant losses;d) Plant design not allowing testwork results to be achieved;e) Operating deficiencies.a} The testwork samples being dissimilar to the plant feed occurs on a very high proportion of projects. The effects of this can beccr.ie exaggerated because the upper levels of the mining company often regard the original testwork figures as sacred and therefore base their judgement of current plant performance on these figures.Frequently the test work samples represent only a minor part of the orebody or alternatively a single composite of the whole ore body is used for the testwork long before it has been determined that all of the potentially different ore zones behave in the same manner. These errors can be compensated for by repeating the ""testwork tests 11 on current plant feed on a routine basis and using these tests to determine whether or not the plant is operating satisfactorily."

Jan 1, 1982

By I. Silin, M. Stapelmann, H. Wotruba, K. M. Hahn, C. Gerold, J. Katzmarzyk

New deposits are often characterized as low-grade and complex ore bodies. To date, processing of fine grained ore deposits implies complex processing routes with high energy consumption. For that reason, the investigation of dry grinding, e.g. with vertical roller mills (VRM), is an approach to save energy reserves. It is already proven that dry grinding can influence subsequent processing steps. In terms of flotation, the surface characteristics of the minerals are crucial for a successful flotation process, e.g. the sufficient adhesion of mineral particles and air bubbles. Wet grinding results in different surface properties of the product entering the conditioning stage than dry grinding, which has direct influences on the subsequent flotation process. To investigate the consequences for flotation, processing of a copper sulfide ore containing chalcopyrite and bornite was investigated, including grinding and rougher flotation. The effects of wet tumbling mill and dry VRM grinding on the degree of liberation of valuable minerals are characterized using mineral liberation analysis by scanning electron microscopy. The obtained flotation results, as well as the recorded flotation parameters such as dissolved oxygen, oxidation reduction potential and conductivity are presented and discussed. INTRODUCTION Copper production is mainly connected to porphyry copper deposits as main source for copper sulfides such as chalcopyrite and bornite. State-of-the-art processing of these deposits is already established worldwide for decades, combining crushing, fine grinding and subsequent flotation with rougher, cleaner and scavenger stages (del Villar, Desbiens, & Maldonado, Bouchard, 2010). While the demand for copper is increasing, copper grades of the deposits are decreasing and the remaining ore bodies have more complex mineralogy and finer particle size distribution. This implies processing routes with high water and – due to the liberation of fine grained valuable minerals – high energy consumption by fine grinding. One of the main energy consumers in processing plants is the grinding section, which accounts for more than 50% of the energy consumption in processing plants and even 4% of the worldwide energy consumption (Jeswiet, & Szekeres, 2016). Therefore, dry fine grinding alternatives are applied to enhance the overall energy consumption of mineral processing plants: high pressure grinding rolls (HPGR) and vertical roller mills (VRM).

Jan 1, 2019

By A. E. M. Warner, A. Vahed, P. J. Mackey

In the decade 2002 to 2012 some 6.7 million tonnes of new copper concentrate production capacity was brought on line, corresponding to 2 million tonnes of contained copper. This increase in concentrate supply necessitated the commissioning of a number of new copper smelters as well as the modernization and/or expansion of existing plants to meet the demand. This paper gives an overview of the copper extractive industry, reviews recent copper production trends and changes in the copper industry, including an examination of pyrometallurgical and hydrometallurgical technology developments. WorleyParsons has supported a number of the projects involved in these developments and this role is briefly discussed. The paper introduces a number of ideas related to possible future directions of the copper industry.

Jan 1, 2014

By Jean-Guy L. Gauthier

"With the Ontario Ministry of the Environment stipulating that the cumulative concentration of copper, lead, zinc and nickel in mine mill effluent must be no greater than 1.0 milligram per litre, it has become necessary for the mining industry of find some form of treatment for the removal of heavy metals from effluent waters.To comply with these guidelines, it became necessary for Mattabi Mines Ltd., which is situated 50 miles Northeast of Ignace in Northwestern Ontario, to develop a compact, cost effective and technically sound treatment process to remove heavy metals from their tailings overflow. A design committee consisting of mine metallurgists, environmental engineers, a Dutch research and development team and the equipment supplier engineering staff was set up to accomplish this.Using some new and innovative wastewater treatment equipment, the guidelines established by the Ontario Ministry of the Environment can now be met. The sludge produced from the precipitated heavy metals is sent directly to the concentrator, thus eliminating the danger of re-dissolution of the metals in a landfill site, while recovering some of the valuable metals that would otherwise be wasted in a sludge landfill."

Jan 1, 1980

By K. V. Konigsmann

"The mill at Mattagami Lake Mines treats 3,850 tons per day. The mill feed is a heavy sulphide ore. It is composed ofPyrite & Pyrrhotite - 40%Marmatite - 17%Chalcopyrite - 2%Magnetite - 10%Talc and other Silicates - 31%The sulphides are intimately associated with each other and often finely disseminated throughout the siliceous gangue. An abundance of middling particles exist in the circuit and a delicate balance has to be maintained between concentrate grades and metal recoveries.The metal content of the mill feed fluctuates between 0.4 to 0.7% for copper and 6 to 13% for zinc.The flow sheet of the concentrator is shown in Figure 1.Eight sample streams have been selected for on-stream analysis, namely1. Copper Concentrate 2. Copper Cln Tailings 3. Copper Tailings 4. Zinc Concentrate5. Zinc Rgh Concentrate6. Zinc Cln Tailings7. Zinc Rgh Tailings8. Flotation TailingsThe mill feed is not being analysed. Only a very coarse sample could be obtained which would be difficult to pump, and the fluctuations in the copper content are too small in absolute terms to have much of a bearing on circuit operations."

Jan 1, 1969

By G. G. Li

"A dynamic ventilation-modeling package, VREX, was used to simulate the mine activities through tracking the equipment movements in underground workings and determine the airflow demand for a new production scenario in a ventilation-on-demand (VOD) system. It incorporates the mine development data from a discrete event simulation and balances the ventilation network using the CANVENT ventilation solver. A case study was performed to demonstrate the capabilities of the software, evaluate the performance of the network and determine the potential energy savings for implementing VOD in a deep mine operation.INTRODUCTIONThe ventilation cost of an underground mine can be significant—up to 50% of the mine’s energy consumption could be used to run fans and provide heat/refrigeration to meet the specified production environment for workers and equipment. The VOD system has proven to be more efficient in operating the fans and supplying the amount of air corresponding to the mine activities taking place in underground workings (Hardcastle, Kocsis, & O’Connor, 2006). In order to properly solve and evaluate the VOD system, a dynamic ventilation modeling software VREX—the ventilation rules engine has been developed to simulate the mine activities and determine the airflow demand for each production scenario within an operation period (Dasys & Cameron, 2011).VREX is a decision support tool, backed by the CANVENT mine ventilation solver (Li, Kocsis, & Hardcastle, 2009), for determining the outcomes of network configuration changes over time. The software incorporates the mine development data with ventilation modeling through the discrete event simulation (DES) performed by SimMineTM. As it simulates the air requirements for different vehicles and activities, VREX can evaluate both the performance of the ventilation system and the potential economic benefits of making operational or technological changes (Pritchard, 2010). For example, the model can be used to assess the economic and environmental impacts arising from modifying regulations to support the use of electric or lower emission vehicles. The combination of DES and ventilation modeling provides a new technology to generate the production scenarios according to mine schedules and activities and to determine the potential benefits for various levels of ventilation control, such as time interval and work shift change."

Jan 1, 2019

By Masakazu Daté

Moisture effect has been studied for the CO oxidation over Au/TiO2, Au/Al2O3 and Au/SiO2, in the range of H2O concentration over four orders of magnitude. It has been found that the catalytic activity is generally enhanced by moisture in the reactant gas. The enhancement is as large as two orders of magnitude. Response to the moisture concentration, however, depends on the support oxide, indicating different contributions of the support to the reaction steps. The moisture effect is reversible and the activity is mainly determined by the amount of moisture absorbed by the catalyst. The apparent activation energies are not significantly influenced by moisture for Au/TiO2 and Au/Al2O3. On the contrary, non-uniform conversion curves versus temperature observed for Au/SiO2 are drastically changed, which indicates that the reaction over Au/SiO2 does not take place at low temperatures without moisture. The moisture effect may be probably attributed to the decomposition of carbonate species accumulated during the reaction, while the ?OH group might directly participate in the reaction pathways as a promoter.

Oct 1, 2003

By J. F. Vynne

ABSTRACT This paper examines several of the systems and processes that have been developed over the past few years and are now being utilized by major mining companies on draglines in North America, Australia and South Africa. These technologies include production monitors and reporting systems, GPS navigation systems, structural integrity monitoring systems, structural analysis studies to increase the dragline rated suspended loads (RSLs) and inspection and response strategies. The use of these technologies provides significant increases in dragline production and reduces maintenance costs, downtime and the chance of a catastrophic failure.

Jan 1, 2010

By Bong Sun You

AZ31 magnesium plate of 300mm in width and 40mm in thickness was produced by horizontal continuous casting machine, and its microstructures were analyzed on the surface and in the plate interior. The defect formation on the surface and subsurface, such as side cracks, buckling, pores and segregation, was very sensitive to the casting condition and processing parameters. Especially, casting speed and secondary cooling were the most dominant parameters to control the solidification behavior of magnesium melt, for example the position and shape of the solid/liquid interface in the mould. The cyclic marks on the surface were obvious because the plate were drawn by 4-step cycle and can not be removed. The average grain size of as cast plate measured as 50-65µm at the near surface and 300-400µm in the center of the plate was relatively small because secondary cooling water was applied to control the surface quality resulting in rapid solidification of the melt in the mould.

Jan 1, 2006

By W. Baranek

The paper describes activities undertaken for intensification of copper cathodes production in electro-refining plants of the Polish copper smelters: 'Legnica', `Glogów I' and `Glogów II'. In the 'Legnica' smelter, Outokumpu?Wenmec machine was used for preparation of copper anodes. Intensive studies were conducted in order to optimise copper electro-refining conditions. As the result of them, spacing between the electrodes was reduced to 99 mm, which enabled placing forty-one cathodes in each tank and increasing amperage from 10.8 to 13.0 kA. This modification resulted in the increase of electro-refining capacity to 103,000 tons/y. Intensification of the copper production at `Glogów II' by 18,000 tons/y became possible after development of new electro-refining procedures, including application of a regime of changes in electrolyte level during the cathode cycle, implementation of the changes in location of starting sheets relative to anodes, and in dimensions of the sheets, and modification in the shape of the anodes. Similar works have been performed at `Glogów I', which were concentrated mainly on defining of a new method of anodes preparation, modification of their geometry, determination of optimum current density, composition of a set of inhibitors and of a method of their introducing. The implemented solutions resulted in the increase in electro-refining capacity at `Glogów I' from 207,000 to 240,000 tons/y.

Jan 1, 2007

By B. Schulz, T. Leißner, R. G. Merker

"Ores enriched in critical rare earth elements (CREE) keep on being of particular interest. The CREE are Nd, Eu, Tb, Dy, including Y. In conjunction with beneficiation tests on Y-mineral bearing flotation tailings of complicated mineralogy, the Mineral Liberation Analyses (MLA) was used to work out processing characteristics fraction-wise in terms of modal mineralogy, mineral recovery, locking and liberation, and particle size.Size fractions from mechanical sieving (“real fractions”) as well as fractions created virtually by using filters on the MLA-data of the unsieved head material (“virtual fractions”) were investigated comparatively thereby. The ""virtual-sizing-approach"" features a much simpler sample preparation procedure and considerably lower cost if a fraction-wise investigation of a head sample is needed. It can be conveniently applied to intimately locked ores needing a fine grinding to a particle size distribution (PSD) range below 25 microns for instance. However, its practical use is sometimes disputed in terms of the reliability of the results. Results are shown for the main Y-bearing mineral xenotime and selected main gangue minerals of a low grade REE-ore.The influence of sample representativeness, sample preparation and particle counting statistics turned out to be of crucial importance. Given that all preconditions for reliable results are met, locking characteristics, modal mineralogy, and even PSD trends can be read from virtual fractions.The authors encourage processing engineers to use the virtual approach. They propose practical measures to improve the reliability of the MLA results, identify and tackle conflicting results, and mitigate evaluation problems that may arise."

Jan 1, 2016