Search Documents

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

ONE of the morning sessions at the recent Annual Meeting was devoted to a Symposium on ways and means to expedite geological investigation, and also to promote greater prospecting activity, in Canada. It will be recalled that at the 1940 Annual Meeting, held in Winnipeg, a paper(l) prepared by Dr. G. A. Young, Chief Geologist of the Geological Survey, was presented, and was followed by a Symposium on Geological Investigations in Canada(2). On that occasion, the participants were in the main geologists, and they included the directors or other officials of each of the Provincial departments or bureaus of mines. At the Montreal meeting, the subject was discussed mainly from the point of view of the mining industry. The following pages present, in somewhat summarized form, the several contributions to that discussion.-ED. DR. J. J. O'NEILL(3), who was to have opened the Symposium, was unfortunately prevented through illness from attending the meeting. He had intended outlining the main features of his paper on The Exploitation and Conservation of Mineral Resources in a Balanced Development of Canada, presented at the last annual meeting of the Royal Society of Canada( 4). In his absence, DR.J. A. DRESSER presented a summary of the paper.

Jan 1, 1941

By George Hope, Dave Green, Jacques McMullen

The Est Malartic mill has been treating massive sulphide, copper/gold ore from the Bousquet 2 mine since 1989. The need to minimize copper content in flotation tails which are leached for gold recovery and to produce a saleable copper concentrate led to the evaluation of Conventional, Column and HG flotation methods. The HG method was preferred and two full-scale cells were installed and operated over a two-year span. In 1992, it was decided to expand the mill capacity from 1500 tpd to 2500 tpd. A total of nine additional HG Tank Cells were installed to provide additional roughing and cleaning capacity. The expanded plant has been operating since June 1993.

Jan 1, 1994

By N. Erarslan, M. Serati

"This paper attempts to provide a simple analytical solution for the calculation of the stress tensor induced in a two-dimensional elastic ring of a brittle material subjected to general loading on either its internal or external curved surfaces. Airy stress functions and Michell’s expression in polar coordinates are used, and parametric studies are performed to investigate the influence of loading angle and the geometrical aspect ratio of the ring on the maximum induced tensile stress. INTRODUCTIONA proper and accurate estimation of the tensile strength of a given material is a crucial step in many engineering projects; in particular in rock cutting, since rocks are much weaker in tension than in compression or shear. Both direct and indirect laboratory techniques such as the direct uniaxial pulling test, the Brazilian indirect tensile test (also known as the split cylinder test), and the ring test have been proposed and developed to estimate rock tensile strength. Among these, the ring test, initially suggested by Ripperger and Davids (1946), has become particularly appealing for its ease of sample preparation and its unique breakage mechanism in almost a pure tensile mode. Unlike the Brazilian test in which high shear stresses developed in the vicinity of the contact could interfere with the tensile breakage of the disc specimen, a tensile failure starts away from the loading platens in a ring test (Hobbs, 1964)."

Jan 1, 2015

By Owen Matthews

Introduction For the past year and a half, the mill of Cochenour Willans Gold Mines, Limited, McKenzie Island, Ontario has been roasting arsenopyrite-gold concentrates, prior to cyanidation, by means of a roaster employing techniques that are new and novel. The roaster is known as the Dorrco 'fluo-solids reactor', and the technique as 'fluidization'. The reactor has demonstrated its ability to roast a flotation concentrate containing arsenopyrite, pyrite, stibnite, small quantities of other sulphides, and some lime silicates and carbonates, yielding a calcine consisting mainly of porous iron oxide, plus the gold values. This calcine is readily amenable to cyanidation. Bulk shipments of concentrates to a distant custom smelter, as practised prior to this installation, has thus been eliminated, with appreciable savings in smelting charges, freight costs, and interest losses during shipment and smelting. This is the pioneer installation of fluo-solids roasting at a Canadian mill and up to the present performance results have not been published. It is the purpose of this paper to present the information now available for the benefit of other millmen who may be confronted with identical or similar problems to those encountered and solved at Cochenour Willans.

Jan 1, 1949

By J. Donnelly, A. V. Deev

Substitution of coal and coke by renewable carbon (charcoal) is a low-risk and low-capital path to 50% or more reduction in net CO2 emissions by the steel industry. However, the high cost of charcoal and its low availability in most countries are barriers for the implementation of this approach. Development of an efficient wood carbonisation technology (slow pyrolysis) capable of producing large-volumes of charcoal from low-cost wood feed (e.g. wood wastes or forest residues) is an essential step towards the use of renewable carbon by the iron and steel industry. This paper provides a summary of the progress made over several years of R&D covering: (1) development and piloting of a new energy efficient slow pyrolysis process for production of charcoal from woody biomass at a competitive cost to the PCI coal, (2) techno-economic evaluation of the process. The main feature of the process is that the material undergoing pyrolysis is heated spontaneously without the supply of heat or air to the reactor. This makes it possible to carbonize large volumes of small-sized wood (e.g. wastes and residues) in a single reactor unit and capture high calorific value pyrolysis by-products

Jan 1, 2015

By Karim Ramji

The extractive sector today faces growing social, legal and political risks (SLPs) from so many different stakeholders including national and local governments, name and shame groups, civil society and environmental groups, and the ?Occupy? movement. Beyond these stakeholders, there are the indigenous peoples who have growing legal, social, political and economic influence which can often determine the outcome of the Project. The development curve in the extractive sector from initial exploration to mine start-up has become longer, steeper and more risky and expensive as these SLPs have grown in scope and complexity. Even if a project is permitted or starts commercial production, its ongoing development and operations are also facing these SLPs. The continuous assessment of these SLPs and the strategy to mitigate for them has now become critical for every project in the extractive sector. A project will only be successful if it is able to obtain the legal permits to operate, then withstand any judicial reviews, and then also to be able to gain and maintain the Social License to Operate (SLO). Stakeholder identification, management and engagement are key risk-mitigation tools. This paper focuses on the growing influence that indigenous peoples are now enjoying and the impacts on the extractive sector. Indigenous peoples are a unique stakeholder group because their legal rights and interests to lands and resources, their aboriginal title and rights, are gaining more recognition. When indigenous peoples form alliances with other stakeholders, this simply adds to their growing momentum and leverage, and this can become a daunting challenge for the extractive sector. More due diligence is required by companies to understand and assess the challenges posed by operating in areas claimed by indigenous peoples. There is a real need for mining companies to develop an effective indigenous engagement strategy to address these challenges in order to successfully convert risks into opportunities. Early identification and engagement with the indigenous peoples is required and the goal should be to conclude an Impact Benefits Agreement (IBA) with the affected indigenous peoples. The real objective must be to develop a real and transparent relationship between the company and the indigenous peoples so as to gain and maintain the SLO.

Aug 1, 2013

By R. D. Brown

"When elephants fight, it's the grass that gets trampled". It is becoming increasingly evident that the federal and provincial governments are awakening to the fact that their vigorous scramble for a "fair share" of mineral revenues which kicked off in 1974 has done considerable harm to the Canadian mining industry. Recent public statements made by government officials, particularly at the recently held annual convention of the Prospectors and Developers Association, would indicate that there is a general consensus in the government sector that changes must be made to the mining tax system. However, there is no evidence as yet that there is any agreement among the various governments as to what form these changes should take , who should make them , or when. It would seem to be worthwhile at this time to reflect on where the Canadian mining industry has been vis-a-vis taxes and "where it is at ". This article is based on a recent address given by R. D. Brown, of Price Waterhouse & Co., Toronto, at the annual convention of the American Institute of Mining, Metallurgical and Petroleum Engineers in Denver , Colorado.

Jan 1, 1978

By G. Pouskouleli, T. A. Wheat

"The role and benefits of using statistical methodology in the development and optimization of materials and processes is examined. It is shown that considerable benefits accrue from the use of an appropriate design in which a number of factors (process parameters) are varied simultaneously while the system response such as percent recovery, degree of separation, purity, etc. is monitored and ultimately optimized.Compared with the commonly encountered one-factor-at-a time approach, this schema exploits reduced experimentation (thereby requiring reduced resources [staff, time, dollars, etc.]) yet yields quantitative information on the significance of each factor and their combinations on the measured response."

Jan 1, 1992

By G. H. Gale, M. A. F. Fedikow, L. B. Dabek

Abstract-Rare earth element (REE) data are reported for ores, sulfide-bearing rocks and host rocks from massive sulfide deposits and barren sulfide facies iron formations in Proterozoic volcanic rocks of the Flin Flon-Snow Lake area, Manitoba. Some of the rare earth elements (e.g., Eu), are selectively leached in zones of intense alteration and redeposited together with the sulfides and silicates in the uppermost parts of the alteration zones and at the rock-water interface. Chondrite normalized REE profiles of layered sulfide ores and exhalites proximal to the deposits typically have positive europium anomalies and are enriched in light REE. In contrast, barren sulfide facies iron formations exhibit negative or ‘normal’ Eu profiles. REE data are useful to explorationists in determining the presence of ‘off-hole’ metal-bearing sulfide zones, in distinguishing metal-poor sulfidic layers related to ‘economic’ hydrothermal activity from barren sulfide facies iron formation and in some instances as a means of establishing ‘ore-equivalent’ strata.

Jan 1, 1997

By I. Thobadi, C. Pawlik, K. Bisaka, S. Mokoena, M. Erwee

The PyEarth™ process developed at Mintek has been demonstrated successfully at pilot scale. Nine tons of ore containing 2.3 mass % of total rare earth oxides (TREO) from a dormant mineralogically complex iron-rich ore deposit, was subjected to a concentrating smelting step in a 200 kW DC open-arc pilot furnace and the rare earths from the resulting slag were extracted via a hydrometallurgical route. This ore deposit is practically not amenable to extraction by conventional methods. The testwork results proved that the PyEarth™ process was able to optimize the extraction of rare earths while minimizing waste through the removal of iron as a saleable iron alloy. Reduction of iron to the alloy in the smelting step was found flexible, efficient, and controllable, while rare earths were left virtually unreduced in the slag phase. The slag chemistry is selected to optimize both the smelting and leaching performances as well as the alloy composition. Leaching of the resulting slag was found possible and most efficient in hydrochloric acid amongst other lixiviants tested.

Jan 1, 2017

By D. E. G. Maschmeyer

The operation of the pilot plant for the S-C Copper Process during 1976 has provided the basic data for the design of a commercial-scale plant. This paper introduces the commercial aspects of the S-C Copper Process through the presentation of a process flow diagram, a schematic flow diagram and basic design parameters for 75,000 tonnes per year (tpy) copper rod production from chalcopyrite concentrate. Basic operating requirements are outlined and a preliminary estimate of operating and capital costs for a Western Canadian location are summarized. The results have been compared with a modern smelter/electrorefinery to highlight the advantages and disadvantages of these two alternatives and to show why the new S-C Copper Process technology should be of interest to the copper industry.

Jan 1, 1978

By Ralph L. Rutherford

Geologists or mining engineers familiar with geology are frequently requested by mine operators to give correlation in-formation regarding some mining property with respect to an adjacent area on one at some greater distance. It is the object of this article to mention a few of the difficulties involved in securing this information and to point out some of the salient factors upon which correlation is dependent. In view of the nature of the following discussion, a brief statement of the general character of coal formations .. seems appropriate. Coal formations, by reason of their environment of deposition which is in fresh or brackish water, exhibit the features common to continental deposits, in contrast to those of marine deposits. Such deposits are characterized by rapid variation in thickness and in lithological character both later-ally and vertically. (Plate 1 A). They consist essentially of sandstones and clay shales with all gradations between them, and also a few beds of coal and frequently some conglomerates.

Jan 1, 1924

By J. Gillies

"Those of you who were at last years C.M.P. meeting are aware there was discussion at that meeting concerning the best method of assisting the assayers of metal mines to exchange new ideas and methods of assaying. The opportunity to advise you of what came of that discussion is very much appreciated.There are several societies, including the Chemical Institute of Canada, the Spectroscopy Society and others that could be of some assistance to assayers. However, since these societies cover a rather broad field and not many mine assayers have the opportunity to attend their meetings, it was felt that an organization oriented to the specific needs of the mine assayers would be of more value to them.Several years ago an attempt was made to hold meetings for the benefit of assayers in conjunction with the Conference of Metallurgists held each year by the Metallurgical Society of the C .I.M.M. This did not work because very few of the mine assayers attended the meetings.With the very evident success of the type of meetings the C.M.P. have and the excellent groundwork done by your secretary, Mr. Stevens, in talking about this to mine management and assayers at many mines across the country, it was decided to hold a meeting at Noranda on October 8 to discuss how best we could help ourselves solve our problems.For the initial meeting it was felt that perhaps it would be better to start with a smaller group, so invitations were sent to mines in Ontario and Quebec that were geographically fairly close to Noranda."

Jan 1, 1970

By R. Q. Honaker

A significant problem in ultrafine particle classification is the significant amount of submicron particle by-pass to the coarse particle stream. In classifying cyclones, submicron particle by-pass to the underflow stream can be reduced by decreasing water recovery. Past studies have shown that a reduction can be realized when the feed solids concentration is increased or the apex diameter is reduced. However, both adjustments tend to increase the particle size cut point and negatively affect classification efficiency due to the impact on slurry rheology. The addition of a viscosity modifier to the feed stream of a classifying cyclone improved the classification performance and decreased the particle size cut point over a range of feed solids concentrations. The detailed test program investigated the use of the modifier in conjunction with varying apex diameters to identify conditions that minimize ultrafine by-pass. With small apex sizes, roping conditions were readily eliminated by the addition of viscosity modifiers. The addition of the modifier had no deleterious effect on froth flotation performance, which commonly serves as a downstream separation process. The fundamental and practical benefits of viscosity modifiers in classification processes are discussed in this publication.

Jan 1, 2006

By E. Swartzman

This paper presents a general re-view of the various methods of briquetting coals, with and without the aid of a binder, with special reference to the production of a suitable briquette from Nova Scotia 'fines' for re-blending with industrial coal. From the economic and technical viewpoints, either small stoker-sized briquettes made with about 4 per cent asphalt in standard low-pressure double-roll presses, or briquettes made without binder in high-pressure double-roll presses, appear to be the most reasonable solution at present.

Jan 1, 1959

By A. Chieregato, C. G. Oñate Salazar, D. Martinelli, D. Peila, M. Barbero

This paper is aimed to confirm the possibility to excavate fractured rock masses by using EPB shields, even in presence of relevant water tables. This verification is based on laboratory test experiences carried out at TUSC laboratory of Politecnico di Torino, where the natural material is tested in order to verify the suitability of a certain conditioning technique in particular conditions. This is due to the fact that every case should be studied apart from existing studies on a certain rock type, as other factors such as fragmentation of the rock mass, natural water content and porosity of the rock can considerably influence the final result of the conditioning process. The most important aspects that allow to consider the conditioning of fractured rock masses as suitable are: possibility to create a plastic paste that can transmit the pressure at the front in a effective way; reduce the permeability of the spoil material in order to reduce the possibility of water leakage inside the chamber and eventually in the tunnel; verify the consistency of the conditioned material for the extraction through the screw conveyors and the belt conveyors. For this research an argillitic schistose rock mass, with some quartzitic and calcareous inclusions, has been studied by using different level of conditioning in order to verify the suitability of an eventual EPB excavation through this formation.

Jan 1, 2015

By T. L. Tanton

"The New Helen mine is 12 miles east of Michipicoten harbour on lake Superior. It is 2 miles east of Wawa station, on the Algoma Central railway, with which it is connected by a spur line railway and a highway.The mine was discovered by Ben Boyer in 1898 during the gold rush near Wawa lake, Ontario. The original discovery was of solid hematite ore extending to a height of 100 feet on a hill rising abruptly on the east side of Boyer lake. The property was acquired by the Algoma Steel Corporation and mining was commenced in 1899. The first iron ore was shipped in 1900. The mine was operated until 1918 when the hematite became exhausted at a depth of 800 feet below Boyer Lake level.Drilling at the Helen mine, after 1910, revealed a large body of siderite both below and to the east of the hematite. By 1913, the body was known to be about 200 feet wide, 3,000 feet long, and at least 2,200 feet deep. In this there was estimated to be 100,000,000 tons of proved and probable siderite ore. An adit was driven into this body in 1917, and in 1918 work was suspended. In 1937 the Algoma Steel Corporation proceeded with the development of the New Helen mine by open-cut mining, and the beneficiation of the ore by sintering. Production commenced in 1939 and has since been maintained at the rate of approximately 500,000 tons a year.From 1900 to 1918, inclusive, the total production from the Helen mine was 2,823,369 tons of hematite ore and 51,930 tons of pyrite. From 1939 to the end of 1945 the total production from the New Helen mine was 3,921,455 gross tons of siderite ore.GEOLOGYThe Helen property is underlain by rocks of Precambrian age. For general description, and a statement on the structure of the iron deposits, the map-units are those shown in Fig. 1.The oldest rocks occur in a complex that lies north and south of an east-west trending zone, 1 ½ miles long and ¼ mile wide, in which the iron deposits occur. That part of the complex lying south of the iron deposits includes small masses of altered conglomerate and slate, and greenstones and pyroclastics. Other fairly abundant rocks are sericitic, chloritic, ottrelitic, and carbonatized schists of doubtful origin, and almost massive metamorphic rocks in which a development of carbonate, ottrelite, quartz, and other minerals has obscured a pre-existing schistose structure. Felsite and quartz porphyry are· prominently exposed south of the iron deposits."

Jan 1, 1954

By Yves Prévost, Guy St-Amant, Guillaume Dion

In 2010, the foreseen increase of copper grade in feed concentrate at the Horne Smelter was a significant challenge to maintain a steady copper flow throughout the process. The Horne Smelter process includes a Noranda Reactor, a Noranda Converter, pyro refining vessels and anode furnaces. Of the many challenges involved, improving the single casting wheel performance was one of the key topics. Its reliability had to be improved to meet the new production objectives, as anode copper production was to increase from 170 000 to 225 000 tonnes/year. A multidisciplinary team was dedicated to improve the casting wheel availability. The improvement project allowed pinpointing failure modes and reviewing operational and maintenance practices. The common understanding developed by the team allowed improving small components with a high gain-to-effort ratio. The project allowed reaching operational targets without any significant investment. INTRODUCTION In operation since 1927, the Horne Smelter, located in Rouyn-Noranda, in Quebec, has undergone several technological changes since its original construction. Built to smelt the Horne mine concentrates, the smelter also accepted some local custom feeds from the first years of operation. When the Horne mines stopped production in 1976, the plant became a 100% custom smelter. With the development of the Noranda Reactor (1973) and Noranda Converter (1997), the Horne smelter increased its productivity and improved its environmental performance. Continuous improvement of the Horne process allowed maintaining a high level of flexibility in the operation of the smelter, while improving its overall capacity.

Jan 1, 2019

By Robert D. Brown

"All ten Canadian provinces have now tabled their 1981 /82 budgets . Only the provinces of Ontario, Quebec and British Columbia made more than minor modifications to their tax structures, with both Ontario and Quebec imposing major tax increases. In the past year, the federal budget was also released in the spring. Not so this year: we have that to look forward to in the fall!This month, Tax Notes presents a brief summary of the more significant tax changes introduced at the provinciallevels in the last months.Summary of provincial tax rate changesThe tax changes in this year's provincial budgets were both up and down- but there were far more tax increases than tax cuts.At the corporate tax level, two provinces, New Brunswick and British Columbia, increased their general corporate income tax rate; the former by two percentage points and the latter by one percentage point. Quebec, rather unexpectedly, sharply cut its corporate tax rate on business income, but increased some of its other business taxes at the same time. British Columbia reduced its corporate tax rate on small business income by two percentage points and Saskatchewan by one percentage point."

Jan 1, 1981