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By G. A. Van Wielingen

"The conditioning of natural gas to meet contract pipeline specifications involves in the majority of cases in Western Canada, the appropriation of substantial capital expenditures for treating and processing installations. It is therefore of vital importance to the owners and producers of natural gas to arrive at an appreciation of the economics pertaining to the production and surface handling of their gas reserves at the earliest possible stage of field development. The treating and processing of natural gas often results in considerable changes in composition and related physical characteristics between the wellhead and the point of delivery of the saleable gas. This paper presents a general outline of engineering calculations which can be applied in the pre-determination of the effects that surface handling of gas will have on the composition and physical characteristics of sale-able gas. Emphasis has been placed on the calculation of hydrocarbon dew-points, heating values and shrinkages prevailing at the various stages in the surface handling of natural gas. It is believed that advance information indicating the approximate ranges of these physical properties will facilitate process selection and will provide a basis for the estimation of capital and operating costs of process installations."

Jan 1, 1960

By W. van der Merwe

ABSTRACT With the gold industry processing more complex ores, the online measurement and control of cyanide addition to the gold leaching circuit has become more critical. This paper compares the two commonly employed ‘free’ cyanide online analysis methods (amperometric and potentiometric endpoint silver nitrate titration) with the rhodanine endpoint silver nitrate titration and ion selective electrode methods common at site laboratories. Measurement differences between these methods are presented and discussed for cyanide solutions containing copper and zinc with varying cyanide to metal ion ratios. The resulting cyanide available to leach gold is also compared using these measurement techniques.

Jan 1, 2013

By B. Wasmund, M. Y. Solar, I. Candy

The nickel laterite industry is divided into two camps when it comes to the grade of the ferronickels produced. One group, led by Falcondo and Cerro Matoso, markets high-grade ferronickels in the range of 35 to 40% nickel, while another group, led by SLN and the Japanese smelters, favour lower grades in the range of 20 to 25%. Because the ores processed by these smelters vary widely in terms of nickel content and iron to nickel ratios, it is probably more accurate to classify these smelters in terms of their iron recovery: Falcondo and Cerro Matoso smelt at lower reduction potentials and thus recover only 15 to 30% of the iron in their ores, while SLN and the Japanese smelters are very reducing and recover 45 to 65% of their iron. Low reductions generally imply higher slag losses and lower nickel recoveries, but also lower power and reductant requirements; higher reductions, the reverse. The question is, therefore, whether an economically optimum ferronickel grade exists for processing any given ore. This paper proposes a methodology for determining this optimum grade and concludes that nickel laterite smelters should favour low reductions and production of high-grade ferronickels.

Jan 1, 2008

By James A. Robertson

"The Pronto Mine located at the east end of Lake Lauzon, Long Township, some 12 miles east of Blind River is of historic note being the discovery locality and the first producing mine of the Elliot Lake uranium camp. Radioactive bedrock was discovered in 1949, a commercial deposit was verified in 1953 and production commenced in 1955. Production continued to April 1960: total tons milled 2,264,404 from which 4,643,835 pounds U,O, were recovered at a recovered grade of 2.05 pounds U3O8 per short ton.The orebody is in a bed of pyritic quartz pebble conglomerate at the base of the Matinenda Formation of the Elliot Lake Group of the Huronian Supergroup. The rocks strike east and dip 15 degrees to 20 degrees south and unconformably overlie Early Precambrian granite, the upper surface of which is marked by a regolith. Several diabase dykes cut the orebody which is also affected by albite, chlorite, and carbonate-rich alterations. To the south the orebody is cut by a fault. The orebody is 6to 10 feet but locally 10 to 15 feet thick, has a strike length of 3,500 feet and extends down dip for 3,600 feet to a depth of 1,000feet. Some 300,000 tons of ore grade mineralization remain in the deeper portion of the mine.IntroductionThe Pronto Mine, (Photo I) at the east end of Lake Lauzon in Long Township some 12 miles east of Blind River, is of particular interest as being the discovery site and the first producing mine of the Elliot Lake camp.Production at the Pronto Mine commenced in 1955 and continued until 1960 when the mill was converted to treat copper ore from the nearby Pater Mine at Spragge. A description of both mines, based on material provided by the mine staff, was given in the report on ""Geology of the Spragge Area"" (Robertson, 1970).As little study has been done on Pronto geology or petrology since mine closure, the earlier description of exploration and geology is essentially repeated, but shortened, here- the main change being that the stratigraphic terminology has been amended as recommended by the Federal-Provincial Committee on Huronian Stratigraphy (Robertson et al., 1969)."

Jan 1, 1986

By Dianne M. Lapierre

Mining firms in Canada are increasingly incorporating the social and environmental interests of their stakeholders into their projects in an effort to become more sustainable. Such initiatives have included negotiating Impact and Benefit Agreements (IBAs) directly with would-be impacted, often aboriginal, communities near resource developments in the Canadian north. Why does a mining firm take on this extra time-and cost-intensive initiative when governments and regulatory measures are in place to address social and environmental issues? Past research has paid little attention to the corporate rationales for IBAs. Based on document review and interviews with mining executives, this study investigates the rationales of mining firms that ?over-comply? with legislative requirements by negotiating IBAs or similar types of agreements with communities. The results indicate that mining firms increasingly recognize IBAs as an intrinsic part of the permitting process. When queried, executives regularly identified the negotiation of agreements as ?the right thing to do?. While this response could be read in ethical terms, a commercial rationale is also clearly present. By building strong relationships with nearby communities, addressing community concerns, and directing benefits to local people, all of which are explicitly achieved with an IBA, mining firms are maintaining their long-term financial viability, thus their sustainability, within an evolving industry.

May 1, 2008

By D. M. Baird

"Enormous deposits of gypsum of exceptionally high grade are readily accessible in southwestern Newfoundland. Coming large-scale production from one of these is resulting in renewed interest in deposits which have been known for more than a hundred and twenty years. General stratigraphy and structure of the Carboniferous rocks in which the gypsum occurs are de-scribed. The stratigraphic position of the basal gypsum-anhydrite zone is described. This massive evaporite horizon, which reaches a thickness of about 1,0001 feet, appears at Fishels-Heatherton, where it is largely undeveloped, and again on the nose of an anticline east of Flat bay, where a present production of 20,000 to 40,000 tons per annum is soon to be expanded to make it one of Canada's major producers. Detailed descriptions are given of the several types of gypsum, the relation of the gypsum and anhydrite, and the distribution of sodium chloride in the evaporite beds, and the bearing of all these on the origin of the gypsum are discussed. Brief reference is made to relation to world markets, mining and transportation, grade, and reserves."

Jan 1, 1959

By P. Cleyle, K. McDermott, M. Hall, C. A. Harris

"This paper describes the implementation of an expert system for monitoring and control of the NO. 4 autogeneous mill and spiral circuits at Wabush Mines.This process control system incorporated the mill operating expertize of Wabush Mines operating personnel and was implemented to improve spiral iron recovery and mill productivity by:1. Continuously monitoring the mill power draw and ensuring that the mill feedrate is regulated to prevent damage to the mill motor, while simultaneously maintaining the feedrate at or as close as possible to the maximum feedrate determined by the process supervisor.2. Improving control over the spiral density and feed rate.3. Improving control over both tbe rougher and cleaner wash water.4. Reducing the frequency with which pumps are plugged.5. Allowing modifications to be made easily and quickly to test various operating strategies.This system was installed using COMDALE/C, a real-time Expert System for Process Control. It was readily accepted by the process operators and produces higher production performance in comparison to the other 5 parallel mill lines at a lower power draw."

Jan 1, 1992

By I. E. Wahn, E. A. Boutin

"The Manibridge Mill is unique in its treatment of relatively high grade nickel-copper ore because in the mill design are included one 10' diam. x 10' Maxwell cell, and three 12' diam. x 12' tank cells. These large cells are used as rougher-scavenger cells. Three 8' diam. x 8' tank cells as well are used for cleaning and recleaning of the tank cell concentrate.Flexibility of flow is the main criterion in the tank cell circuit. Targets from these cells are a high grade nickel-copper product with a minimum of talcose gangue.The operation of the tank cells has been encouraging and they have performed well with both low and high grade heads, yielding a high grade concentrate product.Manibridge Tank CellsDescription:The tank cells at Manibridge consist of one 10' x 10' Maxwell cell, three 12' x 12' tank cells, and three 8' x 8' tank cells. The four large cells are currently being used as rougher scavenger cells. The three small cells are used as cleaner cells.Both sets of tank cells consist of Denver steel tank and Super Agitator Mechanisms with steel beam super-structures. The agitator mechanism has a totally enclosed ball bearing spindle housing with a cold rolled steel shaft, and a stanclard standpipe with adjustable collar.The air rings for the tanks were fabricated by Nelson Machinery. Both large and small cells have injection rings with equally spaced air holes in the bottom centre line of the ring.Air is supplied to the tank cells by a Dresser Clark low pressure air blower.The following is a table of pertinent data on the tank cells:"

Jan 1, 1974

PRESENTATION PURPOSE ? Provide an overview of BC?s Environmental Assessment Actand environmental assessment process ? Identify key issues influencing environmental assessments in BC ENVIRONMENTAL ASSESSMENT ACT ? Major project proposals require an EA before a project can proceed ? Considers potential effects of proposed projects and ways to minimize or avoid adverse effects Minister of Environment and the Minister designated as responsible for project category decide whether or not to certify a project or order further assessment

May 1, 2006

By J. A. Allan

OCCURRENCES of salt in Alberta have been mentioned and described by the writer in 1929 (l) and by Cole in 1930 (2). Brine springs occur at a number of places along the valley of Athabaska river north of latitude 56 degrees, and also on the south margin of Salt prairie, twenty-five miles west of Fitzgerald in the vicinity of the 60th parallel of latitude, which is the boundary between Alberta and the Northwest Territories. These salt springs were visited by Sir James Richardson in 1820, and in the same year D. W. Harmon stated that " ... clown Salt river there are several places where almost any quantity of excellent dean white salt may be taken with as much ease as sand along the seashore" (3). One hundred years later, in 1920, when the writer first visited these springs, the "dean white salt" which had accumulated about the springs was about 400 tons ( 4). This paper deals with a thick deposit of rock-salt which has been proved by drilling in the vicinity of McMurray. Particular attention will be given to a well drilled at Waterways early in 1936 by Industrial Minerals, Limited, when a continuous bed of rock-salt was penetrated with a thickness of 199 feet. As this paper is being presented, a salt plant is being completed and a production well is being drilled at the plant. < is salt deposit is in the vicinity of McMurray, close to the junction of the Clearwater and Athabaska rivets, in township 89, range 9, west of the 4th meridian. McMurray is about 240 miles northeast from Edmonton. As shown on Figure 1, Clearwater river, which rises at Methy portage, in Saskatchewan, enters Athabaska river at McMurray. Some three miles above the mouth of Clearwater river, the Hangingstone enters from the southwest. Waterways, where the latest salt development has taken place, is situated at the end of the Northern Alberta railway, a distance of 304 miles from Edmonton. This railway reaches the bottom of the Clearwater valley at Draper station, about 3 miles east of Waterways and near the mouth of Deep creek. The Draper bituminous sand plant is approximately half a mile east of Draper station. About one mile south of the townsite of McMurray, Horse river enters the Athabaska from the east.

Jan 1, 1937

By Wayne D. Goodfellow, William M. Luff, Steven J. Juras

Abstract-Brunswick No. 12 is a vent-proximal massive sulfide deposit that formed above a feeder pipe with associated hydrothermal alteration. Because of the replacement of bedded sulfides deposited above the hydrothermal vent, individual sulfide lenses show the following vertical and lateral zoning outward from the vent complex: massive pyrite-pyrrhotite-chalcopyrite core - interlayered pyrite-sphalerite-galena (Pb-Zn ore zone) - bedded pyrite. The feeder zone which underlies the Cu-rich core consists of an anastomosing network of pyrite-pyrrhotite-chalcopyrite­ quartz veins with variable and generally minor contents of ferroan carbonate, Fe-rich chlorite, sphalerite, galena and arsenopyrite. Hydrothermal alteration of felsic igneous rocks hosting and adjacent to the feeder pipe is represented by an inner zone (zone 1) characterized by sulfide stringers, Fe-rich chlorite, muscovite, quartz, and ferroan carbonate that formed at the expense of feldspars and what was probably glass; outer zones (Il and III) are represented by Mg-rich chlorite and muscovite formation, and the albitization and silicification of K-feldspar. Accompanying these alteration trends is a marked decrease of Na + Ca, and an increase in Fe + Mg + C03 in zone 1, and increases in Mg + Na in the outer zones. The classic zoning of metals within the sulfide lenses, the formation of a feeder pipe below the vent-proximal sulfide core, and the hydrothermal alteration of felsic volcanic rocks cut by the feeder pipe all support a vent-proximal origin for the Brunswick No. 12 deposit. Furthermore, restriction of sulfide stringer mineralization to the footwall sequence, the folding of the stringer zone by an F1 fold, and the difficulty of long distance mass transfer of metals from the sulfides into the host rocks all argue against a tectonic origin for the stringer zone. All of the evidence indicates that the feeder pipe formed during the ore forming hydrothermal event, but has been distorted and in some areas detached from the overlying massive sulfides during subsequent deformation.

Jan 1, 1992

By Bahram Samani

The Bafq - Saghand ore belt (metallogenic zone) is the main region, where the major discovered Uranium resources are located. This belt is a unique Upper Precambrian terrane experienced Katanga ? Pan African tectono ? thermal events. The oldest sialic crust was formed during the middle Proterozoic and followed by K-granite intrusions of Lufilian Cycle (850-800 M.Y.).This event caused Tectono ? Magmatic ? Activization (T.M.A) characterized by intracontinental rifting and associated ore formations. This zone was considered as an iron ore belt in 1960s ? 1970s, and U ? Th ? REE belt in 1980s ? 1990s, but by new discovered of U ? Mo (Co, Au, As, Cu) mineralization is assigned as a U - Polymetal zone, hosting the full sequences of iron oxide (Cu, Au, U) ore forming groups. On the basis of detailed investigations this zone is characterized by the following peculiarities: This zone is the vestigial vessel of Gondwana basement, where the oldest granite and the first platform clastic cover is exposed. This zone is marginal part of Precambrian continental crust, consolidated in 1.3-1.0 B.a. The sub mature continental crust experienced Lufilian Orogenic and Katanga ? Pan African Tectono ? Thermal event by intercontinental rifting, and ore mineralizations. The ore forming stages were sequential processes, started by enriched mantle derived metallogeny, and ended by interaction of silanes/ HACONS (derived from outer core) with crust. The magnetite- apatite (REE, Ti) metallogeny developed from alkaline- ultrabasic magmatic differentiation, capable to from Au- Ni- Sulfide intrusive massifs during 850- 800 Ma. Degassing of silanes/HACONS from deeper level, not only caused mantle enrichment, and plume upwelling as a frontal load, but also played the main role to develop regional Si (-Na-K-Mg-Ca-Co3) metasomatism, and formation of U- Th- Ti- REE- (apatite, magnetite) deposits. The latest (583-510 Ma old) felsic magmatism was major IGU from U-Mo (-Co-As-Au-?Cu?) hydrothermal vein- type deposits. The albitite- type U- Ti- REE (Th) mineralization could be formed by interaction of ascending, and descending solutions along the deep- rooted structural conduits.

May 1, 2007

By S. Kwon, J. W. Wilson

"In salt and potash mines, the time-dependent deformation mechanism should be clearly understood based on in situ measurements to predict the performance of a mining design. In this study, in situ deformation measurements from the Waste Isolation Pilot Plant (WIPP) and other salt and potash mines were used to determine the transition time from the primary to the secondary creep stage and to investigate the influence of adjacent excavations such as a nearby tunnel excavation, panel excavation and/or pillar extraction on rock deformation. IntroductionThe deformational behaviour of underground excavations in salt and potash mines is complex due to the time-dependency of the rocks. When the material properties are determined from laboratory tests, they should be carefully applied to in situ conditions, because in situ conditions are completely different from laboratory conditions. For instance, in situ deformation measurements show that the deformation rate decreases with time similar to those observed in the laboratory during the early stages. However, the rapid decrease of deformation rate does not come from the microscopic strain hardening effect observed in laboratory tests, but mainly from stress relief around the opening after its excavation (Baar, 1977). It is, therefore, recommended to undertake in situ measurements and use them to understand the deformation mechanism.Even though in situ measurements are widely accepted as important information for understanding the deformation mechanism of salt and potash (Barr, 1971; Kovari and Amstad, 1993), not many publications have focused on the fundamentals of data measurement, the application of the measured data, and the development of data analysis techniques. Recently, several new techniques for better understanding the deformation mechanism of rock salt have been developed that are based on in situ measurements. Kwon and Miller (1995) developed a new technique for describing the actual deformational behaviour of an underground excavation in rock salt. The migration of “zero strain boundary,” which represents a no movement boundary around an underground excavation, could be calculated by the technique developed by Kwon and Miller (1996). Kwon and Wilson (1997, 1998) applied neural network techniques to in situ deformation measurements to predict the deformational behaviour of the underground excavations at the Waste Isolation Pilot Plant (WIPP) located in the United States.In this study, in situ deformation measurementsfrom the WIPP site and other salt and potash mines in the United States were extensively analyzed to understand the deformation mechanism of the underground excavations in the rock mass."

Jan 1, 2002

By J. M. Cummings

CONSIPERABLE information on the industrial or non-metallic mineral resources of British Columbia has been published. For a general resume of the subject, reference may be made to a paper presented by A. M. Richmond before the Annual General Meeting of the Institute in 1935 (1). To avoid duplication, the present paper is confined to a discussion of the existing industrial mineral industry of the Province and of the factors governing its present and future development. British Columbia&apos;s mineral production in 1936 had a value approximately 15 per cent of that for the whole of Canada. Preliminary estimates for 1937 indicate that this proportion has been maintained, although the totals have increased about 25 per cent. The following table presents comparative figures, for the year 1936, illustrating the relative importance of the major divisions of the mineral industry in British Columbia and in Canada as a whole.

Jan 1, 1938

By F. McCarthy, W. Zhang, R. McDonald

"The processing of nickel laterites has been a topic of major interest at CSIRO for almost twenty years. During this period CSIRO has collaborated with other researchers and industry in developing a better understanding of existing processes and been actively involved in testing/developing new beneficiation and process options for these ores. The current paper summarises the results of selected studies and highlights improvements that have been achieved. Key topics to be discussed include enhancements in the mineralogical characterisation, beneficiation approaches, improvements in the understanding and application of leaching technologies, the development of synergistic solvent extraction (SSX) for the recovery of nickel/cobalt from laterite leach liquors and the collaborative development of the Direct Nickel process. Future opportunities and key research questions will be briefly examined.INTRODUCTION Nickel laterite ores comprise a significant resource in Australia and according to United States Geological Survey data nearly a quarter of world reserves are located there (USGS, 2016). More specifically, around 95% of Australian nickel resources (laterite and sulfide) are located in Western Australia (Australian Government, 2017). Given the recent closure of Queensland Nickel, essentially all of Australian nickel production occurs in Western Australia and the primary producers of processed nickel products include Nickel West (Kwinana) with ~84,000 t saleable nickel metal in 2016 (BHP Billiton, 2017), Minara Resources (Murrin Murrin) with 46,700 t nickel metal produced in 2015 (Glencore Australia, 2017), and First Quantum Minerals Ltd (Ravensthorpe) who sold 25,882 t nickel as mixed hydroxide product in 2016 (First Quantum Minerals, 2017). The total sales of nickel from Western Australia in the 2015-16 financial year were 175,722 t. The study of nickel laterites at CSIRO recommenced at the time second generation High Pressure Acid Leaching (HPAL) plants were being commissioned at Bulong, Cawse and Murrin Murrin in the late 1990’s. A combination of technical and engineering issues meant that the ramp-up times at these operations were slower than expected and the outcomes resulting from the attendant problems are well documented (e.g. Griffin & Becker, 2000; Reid & Barnett, 2002; O’Callaghan, 2003) while the issues faced at the BHP-Billiton-built Ravensthorpe plant have been addressed by the current owners of this project, First Quantum Minerals Ltd (Piper, 2012)."

Jan 1, 2017

By Robert B. Parsons

"Finance Minister Paul Martin&apos;s second budget might be good for Canada&apos;s mining industry in the long run, but the budget raises a number of concerns for the industry in the near term. The budget papers suggest that the 25% resource allowance is not working as intended, and report that the Department of Finance will be reviewing this valuable allowance. The so-called ""large corporations tax"" rate will be increased. This annual tax, which is imposed on a corporation&apos;s capital even when the corporation is not in production, is particularly harmful to the mining sector.IntroductionThe Honourable Paul Martin, in his second federal budget, emphasized spending cuts and made only modest tax changes. However, two of these tax changes could have a serious impact on the Canadian mining industry: the proposed review of the 25% resource allowance; and, the increase in the large corporations tax rate.Personal Tax Measures Personal Tax Rates UnchangedThe government has been under political pressure not to increase personal tax rates. Mr. Martin&apos;s announcement that rates would not change will be popular."

Jan 1, 1995

By François Robert

The rate of new mineral discoveries in Canada has been declining in the last two decades. In response to the challenge and to stagnating investments in mining-related R&D, twenty Industry partners, supported by PDAC and Natural Resources Canada, established in 2010 the Exploration Innovation Consortium (EIC). This Consortium seeks to promote the discovery of new resources in Canada through coordination and sponsorship of industry-focused innovative and collaborative research and technology development, as well as training and education in mineral exploration. The two main themes of the integrated R&D program focus on exploration targeting in Deep and Mature Environments and in Remote and Covered Terranes.

May 1, 2011

By G. M. Brownell

THE Falcon Lake stock is a small igneous mass, 2.6 square miles in area, which has intruded a belt of older lavas and metamorphosed sediments. It is well exposed and the entire area of its outcrop is taken up with surveyed mining claims, the claim lines forming a grid which makes ideal conditions for a detailed petrographical study of the unusual variations which are found in the composition of this unit (see Figure 1). The study of this mass, which has revealed features of both scientific and economic significance, began in the summer of 1939 when trainees in a Prospectors&apos; Training Camp, a Do-minion-Provincial youth-training project under the writer&apos;s supervision, were, detailed to map rock outcrops on various mining claims. Microscopic study of rock specimens taken on a line across this stock were made during the following winter and proved to be of such interest that a special trip was made the following summer for the purpose of gathering more data, the results of which are presented here. Location The stock is close to the southeast corner of the province of Manitoba, about three miles from the Ontario boundary. It lies between Falcon and West Hawk lakes and less than a mile south of the Trans-Canada highway. It is easily accessible by motor car, as a branch road from the highway leads to the Sunbeam Kirkland gold mine, which is within the inner core of the stock. Previous Work This area was the first in the Province to receive attention from prospectors, who entered it from the adjacent Lake of the Woods district during the days of the mining boom in the 1890&apos;s. Small occurrences of gold, copper, molybdenum, and tungsten ores were found, but to date there has been no production from the district, except for small shipments of gold ore. The regional geology has been mapped by the Manitoba Department of Mines and Natural Resources, the Falcon Lake stock being shown and recorded as of "varying composition". The more detailed work involved in preparing the accompanying map has necessitated only minor changes in the outline as previously mapped.

Jan 1, 1941

By Pingchao Ke, Zhihong Liu

"To overcome the problem that scoroditeis not stable in neutral and alkaline solutions, we proposed and investigated a synthesis method of scorodite coated in-situ with hydrated ferric oxide in the Fe(II)-As(V)-H2O system at the initial Fe(III)/As(V) molar ratios larger than 1.0.The synthesis was carried out at 90?,pH 1.5 under atmospheric pressure. During the synthesis, oxygen gas was conducted and bubbled into the system to oxidize Fe(II) ions into Fe(III)ions, and Na2CO3aqueous solution as neutralizing agent was added controllably into the system for keeping the pH constant at 1.5. In this study, three samples of scorodite were synthesized at the controlled initial Fe(II)/As(V) molar ratios of 1.0, 2.0 and 3.0, respectively. The characterizations of the samples by HRTEM, TEM/EDX, and chemical composition indicated that the particle surfaces of scorodite synthesized at the initial Fe(II)/As(V) molar ratio of 2.0 and 3.0 were coated in situ by a film of hydrated ferric oxide with the thickness of several nanometers, while the sample synthesized at the initial Fe(II)/As(V) molar ratio of 1.0 was uncoated scorodite. The TCLP and long-term leaching for the toxicity characteristic of the samples showed that scorodite coated in situ with hydrated ferric oxide was stable in a wide pH range from 3.0 to 10.0, with the arsenic concentrations in the leaching solutions less than 1.0mg/L. Nevertheless, uncoated scorodite was unstable under the conditions from weak acidity to alkalinity, with the arsenic concentrations in the leaching solutions larger than 5.0 mg/L.INTRODUCTIONArsenic pollution is a challenge for environment and health and has been an important issue for scientists (Hopkin, 1989).Arsenicis commonly associated with ores or concentrates of nonferrous metals, mainly as independent arsenic bearing minerals such as arsenopyrite (FeAsS), tennantite(Cu12As4S13), enargite (Cu3AsS4), cobaltite (CoAsS), and gersdorffite (NiAsS), realgar (As2S2), orpiment(As2S3), etc.(Matschullat, 2000; Mandal & Suzuki, 2002; Long & Peng, 2012). In the nonferrous metallurgical processes, arsenic is enriched mainly in such arsenic bearing materials as various flue dusts, residues, and anode slimes, which results in the accumulation of arsenic in the system owing to the circulation of those arsenic-bearing materials back to the system and the pollution to the environment (Harris, et al, 2003).In addition, the utilization of arsenic is limited and has been decreasing owing to its toxicity and carcinogenicity. Therefore, arsenic has to be removed from those arsenic-bearing materials and discarded safely (Dutrizac & Jambor, 1988; Monhemius & Swash, 1999; Drahota & Fillippi, 2009).In this case, how to immobilize arsenic has become a difficult problem which must be solved. Among the methods of immobilizing arsenic which have been proposed and investigated, immobilizing arsenic into a stable mineral to fix it, has been realized as a promising method and becomes a research focus(Dutrizac et al, 1987; Dutrizac & Jambor, 1988; Demopoulos et al, 1995; Fujita et al, 2008a; 2008b).Scorodite has been known as one of the best minerals for immobilizing arsenic, owing to its high stability under weak acidic condition, the arsenic content as high as 32wt%,and good crystallinity benefiting the separation of solid to liquid(Daivid et al, 1999; Zhu & Merkel, 2001). Scorodite can be synthesized from arsenic containing solutions under both hydrothermal and atmospheric conditions, and a lot of work has been done on the synthesis of scorodite and its leaching stability characterization (Filippou & Demopoulos, 1999; Gomez et al, 2011).Two plants for the immobilization of arsenic as scorodite have been putin to operation in Chile and Japan, respectively (Filippou & Demopoulos, 1999; Amir et al, 2016)."

Jan 1, 2017

By Corrie Pitzer

Safety performance in many companies and even industries has stalled in the few years. Accidents rates are at a ?plateau? and yet, serious accidents and fatality rates are not. In more dramatic cases, such as in the BP Texas disaster, organizations that have ?exemplary? safety statistics, suddenly have a catastrophic or multi-fatality event occurring. Other classic examples are the Piper Alpha disaster and NASA?s Challenger and Columbia disasters and even the Chernobyl nuclear reactor. Looking into the root causes of these accidents provides an insight into the events and deficiencies that led up to the accident, but what are the common features in the organization?s mindset? What characterizes these organizations? decision making, their approach to safety and to risk and are there specific cultural features that can be delineated? The research and review presented in this paper covers a period since 1994, which started in the Australian resource industry and since then covered international events. The features of these organizations are summarized as the seven deadly delusions, based on extensive research since 1997 of organizations that suffered unexpected disasters. Their huge focus on safety, the achievement of lofty goals and celebration of safety successes led to ?mindset? that they are leaders in safety, protected by an extraordinary safety system and that their safety incident figures indicated a truly world-class safety performance. It led them into the trap of the seven deadly delusions?

May 1, 2011