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By S. Hobo, M. Yagisawa, T. Uchida, C. Tokoro, T. Kato

In this study, quantitative modeling was carried out for the treatment of simulated waste water containing As(V), Zn(II) and Hg(II) as toxic elements, and Fe(III), Na(I) and sulfate as coaxing ions. The objective was to predict the pH and residual concentrations of all the elements in solution after the neutralization/co-precipitation treatment. To accomplish this, the removal mechanism for As(V) and Hg(II) by ferrihydrite precipitation was first investigated for simulated waste water containing only As(V) or Hg(II). From the experimental results, it was confirmed that the removal mechanism involves not only surface complexation but also surface precipitation. However, surface complexation is the main mechanism for As(V) and Hg(II) removal to meet the target levels regulated in Japan. Next, the surface complexation model was constructed for the removal of As(V) and Hg(II) by ferrihydrite. The specific surface area and site density were determined from reference values proposed by Dzombak and Morel (1990). By comparing the experimental and calculated results, it was confirmed that our constructed model could successfully represent the experimental results. Furthermore, the surface complexation model was coupled with chemical equilibrium calculations and applied to the neutralization of simulated waste water containing As(V), Hg(II), Zn(II), Na(I), Fe(III) and sulfate. The constructed model could successfully represent the pH edge for As(V), Hg(II), Zn(II), Fe(III) and SO42- removal. In addition, the constructed model could represent the ion balance. Thus, our constructed model is useful to estimate the amount of neutralizer that is needed to achieve a target pH.

Jan 1, 2016

By Eric D. Marks

Fatalities resulting from ground workers colliding with objects and construction equipment accounted for approximately 18% of the total construction fatalities experienced in 2010. Current injury and fatality measuring methods have proven to be inadequate due to their use of passive measures of safety rather than a more active approach, such as the use of leading indicator data (also called near misses) of hazardous proximity situations between ground workers and heavy equipment on construction sites. The objectives are to create and evaluate the effectiveness of a reliable algorithm for collecting and analyzing the resulting leading indicator data from hazardous proximity situations. Numerous experiments emulating typical interactions between workers-on-foot and heavy equipment are used to evaluate the proximity sensing and detection technology. Safety leading indicator data (also called near misses) generated by the proximity sensing and detection technology during the experimental trials are used to create and assess the resulting algorithm. Results from the experiments indicate that leading indicator data generated from these systems can be processed and analyzed to identify hazardous proximity situations and incidents on construction sites.

Aug 1, 2013

By P. Keller, T. E. Lister, G. G. Clark, L. A. Diaz

As electronic technology continues to evolve there is a growing need to develop processes which recover valuable material from antiquated technology. This need follows from the environmental challenges associated with the recovery of raw materials and fast growing generation of electronic waste. Although present in small quantities in electronic devices, the availability of raw materials such as rare earths and precious metals becomes critical for the production of high tech electronic devices and the development of green technologies (i.e. wind turbines, electric motors, and solar panels). Therefore, the proper recycling and processing of electronic waste presents an opportunity to stabilize the market of critical materials, providing a proper disposal and treatment of a hazardous waste stream. This paper describes the development and techno-economic assessment of a comprehensive process for the recovery of value and critical materials from electronic waste. This hydrometallurgical scheme aims to selectively recover several value streams (base metals, precious metals, and rare earths) present in electronic waste. The economic feasibility for the recovery of rare earths from electronic waste is mostly driven by the efficient recovery of precious metals, such as Au and Pd (ca. 80 % of the total recoverable value). Rare earth elements contained in magnets (speakers, vibrators, and hard disk storage) can be recovered as a mixture of rare earth oxides which can later be reduced to the production of new magnets.

Jan 1, 2016

By Werner W. Scholz

A corrosion-resistant lining is, quite often, selected on the merits of its corrosion resistance only. This paper demonstrates the effects of temperature, pressure, weather, design aspects and variances of physical properties within the scope of the generic designation of a corrosion-resistant material or materials. The base for the study is a rubber- and brick-lined steel vessel, with unchanged chemical conditions. Graphs and sketches illustrate the various effects of physical influences on the selected lining specifications.

Jan 1, 1979

By Ahmad Ghahremaninezhad, Noelene Ahern, Yeonuk Choi

Arsenic (As) is a toxic element and is a major contaminant in the extraction processes of some metals (e.g. gold and copper). Due to the toxicity of arsenic species, its removal from As-containing streams from extractive metallurgy processes and safe disposal is absolutely necessary. For nearly complete removal of waste arsenic species from metallurgical process streams, it is required to have arsenic in its pentavalent state (As5+ species). This study presents an oxidation process for arsenic species with air or oxygen gas as oxidant. Activated carbon (AC) or other carbon based materials are used to catalyse the oxidation reaction. Air or oxygen gas is the only consumed reagent which makes the economy of the process very attractive. The oxidation reaction can be carried out at ambient conditions (room temperature and atmospheric pressure) in less than 24 hours.

Jan 1, 2014

By Robert B. Parsons

"It is quite likely that more than a handful of junior exploration companies will receive some startling news from their accountants this spring when 1989s tax returns are being prepared. These companies could find that, for the first time ever, they will have to write a cheque to the federal government on account of a new federal capital tax which became effective July I, 1989IntroductionMany mining companies which have never had to pay a federal income tax are finding that they indeed have a tax liability for 1989. Non-producing companies, such as junior exploration companies, almost automatically assume that they don't have to pay any income tax. But, a new tax imposed under the Income Tax Act catches especially the company that has no income.Effective July 1, 1989, a federal capital tax (some call it a corporation minimum tax) is payable by any corporate carrying on business in Canada where the corporation has ""taxable capital"" exceeding $10 million. As a result of the popular use of flow-through shares in recent years, many junior exploration companies are finding that their balance sheets show capital stock over $10 million, and that they are consequently caught by the new tax. Further, some of these companies are finding, to their chagrin, that the tax for 1989 was due on February 28, 1990, and that non-deductible interest is ticking away on unpaid taxes."

Jan 1, 1990

By J. Font

New approaches for the fire refining process of blister copper have been carried out at the Codelco Norte Smelter. These have been mainly focused on modification and improvement of the process configuration based in fluid-dynamic and metallurgical studies of the oxidation and impurity treatment stages. This paper presents the results of the laboratory simulations and industrial tests performed in the 250 t anode furnace, evaluating two different process configurations: ? Bottom Bath Agitation System in the vessel during the oxidation stage, ? Dual Flux Injection System during the impurity treatment stage. The results show the possibilities of effective removal of high content of sulfur from the melt during the oxidation stage by using the bottom bath agitation. The use of the dual injection system demonstrated the significant improvement in the removal efficiency of impurities. Cu2007

Jan 1, 2007

By Robert B. Parsons

"Several recent cases indicate that the Courts may be leaning toward a more favourable treatment of mine closing and related costs. In this article, we look at two recent cases, Burnco Industries Ltd. and Nomad Sand & Gravel Ltd. The former was heard before the Federal Court - Trial Division and the latter before the Tax Review Board.It appears that in certain situations mining companies may now be able to sustain current deductibility of estimated mine closing costs during the productive years of the mine, rather than waiting until either the date on which mining ceases or the reclamation and similar activities commence. This would be of great benefit to the mining industry, as waiting until the bitter end often means that there are no revenues available against which the expenses may be offset and, hence, no tax relief.IntroductionUnder the Income Tax Act in Canada, taxpayers are not permitted any deductions in respect of an outlay or expense in determining income from a business or property, except to the extent that such expenditures are made or incurred by the taxpayer for the purpose of gaining or producing income. In addition, no deductions are permitted for amounts transferred or credited to a reserve, contingent account or sinking fund except as expressly permitted by the Act.In large measure, these provisions are relevant to the mining industry to the extent that they determine the periods during which expenses may be charged against revenues for income tax purposes. Several recent cases have indicated that the Courts are leaning toward a more favourable treatment of accrued costs in the mining industry than was previously considered to be the case."

Jan 1, 1982

By W. G. Schultz

"Sylvite's potash mine, which produces 8,000 tons of ore per day, probably ranks as one of the most highly mechanized and automated mining operations in the world. Employing, on a normal 10-hour production shift, one supervisor and a crew of seven operators, Sylvite is able to mine at an average rate in excess of 600 tons per hour. The ore is produced by two Marietta miners weighing 258 tons, the largest and heaviest pieces of equipment ever taken underground. The ore produced by these two Marietta miners is conveyed to the shaft area, cycled through a 15,000-ton storage system and hoisted to surface completely automatically. The operation of all equipment in the mine can be monitored and controlled from a central control panel located underground. Because Sylvite's mine is a new operation with equipment of a new design, the full potential of the operation has not yet been realized. The ultimate capability is clearly evident from the success Sylvite has had over the past year as the average mining capability has risen from 100 tons per hour to 600 tons per hour."

Jan 1, 1973

By R. L. Alexander

"Madawaska Mines Limited, incorporated in 1975 is the successor to Faraday Uranium Mines Limited. The history of the latter's mine development and corporate changes are outlined. This paper describes the geology of the Bancroft area and the rock types found in the mine, particularly the pegmatite which is the host rock for the uranium. The structure, mineralogy and distribution of the ore shoots are described with the method of grade control and mine development. The paper concludes with a summary of the production and mineral reserves.Location, Access, and PropertyMadawaska Mines Limited is located in Faraday Township, Hastings County, Ontario. The mine is in the N.T.S. quadrant 31 F/ 4, Bancroft sheet and near 46 degrees 01 minute latitude, 77 degrees 46 minutes longitude. The mine is one-half mile north of Highway 28, five miles (8 km) west of Bancroft, and is accessible by various highways from Toronto, Ottawa, Peterborough, and Belleville. (Fig. 1). A landing strip for small aircraft is located at the northwestern edge of Bancroft. Bancroft is a modern community with a population of 2,400. The company has the mineral rights to 2982 acres (1207 hectares) surrounding the mine workings and plant which are situated in the north parts of Lots 16 and 17, Concession XI, Faraday Township."

Jan 1, 1986

By J. Janzen

The cost to supply ventilation may exceed 40% of the total mine energy cost for underground mines and is often higher for deeper mines. The goal of Ventilation-on-Demand (VOD) is to ensure that the required quantity and quality of air is supplied to underground mining crews and diesel equipment at the least energy expenditure (minimum cost). A VOD system may include control of surface fans (Supply & Exhaust), underground booster fans, auxiliary fans and automated regulators/dampers to regulate the flow of air with more control elements providing more value. Strategically located Air monitoring stations measure air quantity and quality and provide feed-back enabling control. The modular design involving controls, intelligent instrument and intelligent motor control centres coupled with a communication network allows the quick installation, commissioning and expansion of the system as the mine develops. The result is a very robust, flexible system while reducing maintenance costs and spare parts. This paper discusses the impact of sensors, installation and commissioning on advanced controls and provides solutions for in-field applications.

Aug 1, 2013

By J. Reinhardt, R. Uken, S. S. Chinnasamy

Au mineralization in the Kilpwal Gold Mine is confined to laminated quartz-carbonate lodes and associated alteration along the Klipwal Shear Zone (KSZ) in the upper Mozaan Group of the Mesoarchaean Pongola Supergroup. The brittle-ductile shear zone is characterized by inner and proximal hydrothermal alteration domains that are comprised of chlorite, epidote, sericite, pyrite, arsenopyrite and gold. Possible sources of gold are: (i) paleo-placer U-Au rich conglomerates from the lower Mozaan Group; (ii) the underlying mafic volcanics of the Nsuze Group; (iii) greenstone belts in the basement to the Pongola basin. Post-Pongola granites probably provided the heat to mobilize auriferous fluids into the KSZ.

Jan 1, 2011

By Terry Aben

Outline ?Review of standards that can be used to identify current coating conditions and optimal points to perform coating maintenance. ?Identify how standards can be used to extrapolate the future condition of coatings to achieve predictive maintenance planning. ?Demonstrate how the above can be combined with project estimating to generate a data driven, quantitative, predictive, risk-based asset integrity maintenance program for Protective Coatings. The Value of Asset Integrity Programs ?Maximize the benefit produced from the investment in maintenance spending. ?Get the best bang for your buck! ?Don?t perform maintenance work before it is necessary ?Money is invested early with no increase in the service life extension. ?Don?t delay until it is too late. ?Planned Maintenance is far less costly than Reactive Maintenance. ?Identify the Optimal Point for Maintenance.

Nov 1, 2011

TIPS FOR SUCCESSFUL WASTE MANAGEMENT ? WASTE MANAGEMENT PLANS ? Define the question to be asked in waste characterization studies ? Calibrate assessments and designs with field conditions ? Ensure consistent with short, medium and long-term mine plans ? Design robust plans - goalposts and expectations will change ? Fully assess and integrate costs into economic models ? Integrate waste specialists into the feasibility and design teams ? Keep it simple and when you can?t, communicate it in simple terms ? PLAN EXECUTION ? Integrate the waste management plan into daily mine operations ? Identify the critical KPI?s , track them and set clear action triggers ? Know the difference between knowledge and data ?make sure you retain knowledge and document the important Maintain management, engineering and operational focus through the mine life

May 1, 2010

By F. Rosenblum, P. Spira

"A correlation has been established between the oxygen demand of Brunswick Mining and Smelting ore and flotation results at the bench, pilot plant and operating plant scale. A method of dete""1llining the aeration requirement of sulphide ores on the basis of this correlation is presented. It is shown that abraded iron from grinding media plays an important role in aeration and flotation. Laboratory grinding must therefore be conducted under controlled conditions with suitable grinding media in order to obtain the true aeration requirement of the ore.A method of evaluating aerator efficiency, also based on oxygen demand measurements, has been used successfully at Brunswick Mining to design pilot plant and full-scale aeration systems.1. IntroductionPre-flotation aeration of sulphide pulps has been practiced in the Noranda Group for many years to help in the depression of pyrite and pyrrhotite and to promote chalcopyrite and/or galena. Recently, two out of three parallel circuits at the Brunswick Mining and Smelting Corp. Ltd. concentrator have been converted on a test basis to a new flowsheet incorporating aeration as a basic step. Among other benefits, a substantial decrease in the middlings load has been achieved as a result of improved pyrite rejection. There has been increasing interest in other organizations in the potential advantages to be derived from' aeration in terms of improved metallurgy and/or decreased reagent consumption."

Jan 1, 1978

By Peter Van-De-Velde

"The results of applying Japanese pumping technology to North American reclamation projects will be discussed.IntroductionEconomic high-density mineral reclamation and subsequent transportation of solids through a pipeline presents many formidable engineering problems.In North America where space has rarely been a facto r, industry has generally relied upon the traditional dumping of material into various waste ponds, etc . In Japan, where confined geographies and stringent environmental regulations are enforced, alternative solutions for disposal or reprocessing of waste material had to be found.High-density mineral reclamation system designed by theoretical formulas is almost impossible because solids composition, i.e. concentration, velocity, moisture content, solid size, etc. can only be controlled within a broad pumping range.Traditionally this has restricted dredging of material to relatively dilute slurries whereas it is usually preferred to reduce water usage with its associated power and reclamation costs to a minimum and reclaim as high a concentration as possible.At Toyo Pumps North America we recognized these pumping limitations and began to develop and manufacture a range of standard and auxiliary equipment that would exceed these technical restrictions."

Jan 1, 1985

By Brian Penney

"The Iron Ore Company of Canada (IOCC} has mined and processed an iron deposit in Western Labrador along the Labrador-Quebec border since the early 1960' s. Current capacity is approximately 19 million tonnes of concentrate, 70% of which is converted to pellets at these facilities.The ore deposits are located in hills rising 150 to 300 meters above the adjacent lakes, and most of them are covered by very little overburden. The iron minerals are mainly specular hematite and magnetite hosted in a quartz formation. Crude ore averages 40% Fe that is concentrated to 65.5% Fe. IOCC is an extensive operation extending from Labrador City NF to Sept-Iles Quebec. It consists of open pit mining, concentrating, pelletizing, railway, and dock loading facilities.The Concentrator liberates iron from the silica by crushing and grinding the ore to -14 mesh (-1190 microns}. Ground ore is concentrated in spirals and filtered for transportation. Spiral tailings are treated in a Magnetic Recovery Plant (Mag Plant} that recovers lost magnetite. Mag Plant tailings are treated in a Hematite Spiral Plant (Hem Plant} that scavenges fine iron remaining in this stream.This report deals with ongoing iron recovery initiatives within the ConcentratorIron Losses in the ConcentratorIron recovery at IOCC is approximately 70.5%. This compares with recoveries that range from 65% to 86% for other iron mines in our area. Other world large iron ore producers dig and ship concentrate quality ore directly out of the ground and have an effective recovery of 100%. With increasing costs for labour, equipment, and supplies an increase in iron recovery is required to keep the operation viable.More than 90% of our iron concentrate is produced by gravity separation using spirals. The physical characteristics of the iron minerals that most effect recovery are mineral grain size and degree of liberation. We divide ground ore into three size categories -coarse, intermediate, and fines. A brief description of each size fraction follows:"

Jan 1, 1996

By J. F. Perreault, J. Paraszczak

"The profitability of an underground mine depends to a great extent on the production cost.Random equipment failures and their consequences have significant influence on the total operating cost of a mining system. Having this in mind, a reliability study has been initiated for loadhaul- dump machines in an underground mine. The main purpose of this study is to identify the critical machine subsystems, determine their failure pattern and help work out an effective maintenance strategy. In the first part of this study, the failure data of diesel powered LHDs, gathered during an I8-month period have been analyzed. For the purpose of the analysis, the machines have been treated as systems comprising seven subsystems connected in series. The most critical subsystems, i.e. electrical and hydraulic, were further investigated, and analyzed by graphical and analytical methods. Different failure distribution models were applied and discussed. Basic Defmitions and ConceptsIn order to avoid confusion, several terms used in this paper are defined below, as compiled by O'Connor (1991). The acronymsBS and MIL-STD stand respectively for: British Standard and US Military Standard.Failure: the termination of the ability of an item to perform a required function (after BS 4778).Time Between Failures (TBF): the length of time between two consecutive failures.Observed Mean Time Between Failures (MTBF): For a stated period in the life of an item, the mean value of the length of time between consecutive failures computed as a ratio of the cumulative observed time to the number of failures under stated conditions (after BS 4778).Maintenance, Corrective: The actions performed, as a result of failure, to restore an item to a specified condition (after MIL-STD-721 B).Maintenance, Preventive: The actions performed in attempt to retain an item in a specified condition by providing systematic inspection, detection and prevention of incipient failure (after MIL-STD-721B)."

Jan 1, 1994

By Isabel F. Barton, Matthew J. Gabriel, Mark D. Barton

Process control, mine-to-mill optimization, and other mining operations depend on having robust, comprehensive mineralogical and chemical characterization. However, current characterization methods rely primarily on analyzing samples from trenches, channels, blast holes, and drill holes and interpolating between them, and are not always sensitive to some minerals (such as clays) that cause major problems for mining and mineral processing. Continuous characterization is possible with techniques such as hyperspectral remote sensing, which measures reflectance or absorption of light in the visible to near infrared (VNIR) and short-wave infrared (SWIR) regions of the electromagnetic spectrum. Absorption and reflectance features are characteristic of different chemical bond types, so each spectrum corresponds to a different mineral or material. In remote sensing, each pixel in the scanned area has both a location and a spectrum. This makes hyperspectral remote sensing potentially useful for characterizing mine site materials. In this study, we tested a hyperspectral remote sensing system as a method of characterizing the mineralogy and material types at mine and metallurgical sites. Our test site was a small open-pit copper mine and leach operation in the southwestern U.S. We scanned mine highwalls, dump piles, leach pads, and nearby rock outcrops with drone- and tripod-mounted VNIR-SWIR spectrometers. We collected ground-truth data through geologic mapping, sampling, and spot analyses with a portable short-wave SWIR instrument. The results show that the hyperspectral remote sensing system that we tested is capable of distinguishing the types and distribution of spectrally active minerals and other materials in diverse mining settings, including showing wet and dry areas of leach pads; clay and carbonate type and distribution on mine highwalls, leach pads, dumps, and rock outcrops; plant type and distribution; fault zones, bedding planes, and other geological features; and qualitative spectral matches between dump piles and areas of the mine highwalls. Hyperspectral sensing proved particularly sensitive to the presence and type of clay and carbonate minerals, which cause geotechnical and metallurgical problems such as highwall failure, gangue acid consumption, and flotation sliming. Examples will be presented and discussed at the conference. Areas of continuing research include automating and streamlining the data reduction process, integrating hyperspectral data with block modeling and mine planning software, and testing the results of hyperspectral sensing in different geological environments.

Jan 1, 2019

"Cambior currently has nearly 80 exploration properties, acting as operator on about 60 of these. The company's exploration budget has increased to over $11,100,000 for 1990. On-going efforts recently yielded a new gold discovery on the Douay- Vezza property, a joint venture project with Inco and Vior. Cambior continues to seek out new opportunities, recently acquiring an option agreement on the Sleeping Giant project in Quebec and four new exploration agreements in the United States, through its Reno office. Other nearly-concluded joint venture agreements have also given the company entries into Indonesia and Guyana.SummaryWhen it acquired SOQUEM's assets on August I, 1986, Cambior also acquired interests in 45 exploration projects. The subsequent mergers with Aiguebelle Resources and Sullivan Mines in 1987 brought the total number of exploration projects to 83, most of which are concentrated in northwestern Quebec. Cambior's strategy emphasizes gold exploration, and exploration activities were, therefore, initially limited to the Val d'Or and Rouyn-Noranda mining camps, where Cambior has a large portfolio of properties. Approximately $25.8 million has been spent on surface exploration in this area since the formation of the company, resulting in the discovery of the Mouska deposit and four sub-economic zones on the Porcupine, Forbex, Bloc Sud and Flavrian project s. In 1988, Cambior became involved in projects in the United States to which the company expects to allocate about 38070 of its 1989 exploration budget."

Jan 1, 1990