Search Documents

By Christopher R. Davis

Resource modelling is the basis for any economic appraisal of a mining project and includes a number of steps from data acquisition and validation to resource reporting and classification. At each step in the modelling process it is necessary to define the specific objectives, the methodology proposed to achieve those objectives and to establish a set of checks and validation tools to assess the effectiveness of the proposed methodology. The data used has to be both reliable and relevant for the purpose of the modelling. QA/QC for database validation requires verification of sample location; including correct collar location, topographic modelling and down-hole surveying. Validation is also performed on assaying information such as checks for sampling bias and accuracy of core splits, proper use of pulp duplicates and standards, handling of calculated values, explicit/implicit absent data and data entry errors. The second step involves identifying the mineralized domains resulting from the mineralization process. This step requires a geometric interpretation of all relevant geological features that have influenced the spatial distribution of the mineralization including dykes, faults and alteration. In addition, a geologic reference system rather than a standard Cartesian system is established to measure distances between samples. Once the mineralized domains are established and the database has been validated, statistical and spatial description of the mineralized samples are examined in order to establish the histogram and the variogram of all variables of interest and their correlation. Results are also used to calibrate the global resource estimate within the mineralized domain and to establish the search strategy for grade interpolation. The mineral envelope is filled with polyhedral cells representing mining blocks. The average grade of these blocks is estimated using kriging techniques in order to eliminate global bias and to minimize the local error in the block grade estimate. Visual checks are made to validate the spatial trends in grade distribution while global bias and smoothing effect are assessed from the declustered sample statistics. When required, smoothing correction may be applied using ?change of support? techniques. Simulations are used to perform sensitivity analysis and the simulation models are used if severe smoothing of spatial variability makes the interpolated model inappropriate for mine planning. The keys to successful resource estimation are an integrated team of geologists, geophysicists, geostatisticians and mine engineers using the best available technology and reviews by independent auditors. The resource team is also responsible for performing a QA/QC program in order to measure the effectiveness of the methods in meeting the specific objectives at each step of the modelling process.

May 1, 2001

By J. E. Rehder

IN A DISCUSSION of use of any material of ?construction in the mining industry, two points of view must 'be kept in mind - that of the producer or manufacturer of mining and metallurgical equipment, and that of the maintenance and operating staff of the mining plant. In the first case, the choice of material of construction is up to the manufacturer and the user of the equipment has little direct say in the matter. However, if materials are badly chosen and the equipment does not function properly, wears out rapidly, or costs too much, repeat orders ?will likely go to a different manufacturer, so that, in the end, the consumer or mine operator does have the final voice. In the case of materials for maintenance work and plant operations, however, .the mill personnel have direct control over purchases and it is then that a well-balanced knowledge of materials, their properties, and their costs, can be directly useful. With all materials of construction, the final criterion is unit cost versus service performance, so that the lowest possible total operational cost will be obtained. Sometimes this means using the cheapest material available, sometimes the most expensive, but in any case careful analysis of service performance, replacement cost, and material cost is essential to determining the material that produces lowest total cost.

Jan 1, 1956

By Frank E. Lathe

During the war the National Research Council at Ottawa sent out questionnaires to the managers of nearly all the industrial plants in Canada. Inquiry was made as to the research equipment possessed, the number of research workers employed and the nature of the research problems which still remained unsolved. Practically all the companies reported that they had no special facilities for research, had no re-search workers and did not require the assistance of the National Research Council-because they had no research problems. Perhaps we have here one of the chief reasons why certain of our manufacturers find themselves unable to meet foreign competition. For hundreds of years the Indian tribes of northern Chile worked, in a small way, the copper deposits at Chuquicamata. They had no research problems and made no striking success of their mining operations. Then came an American company with a research problem, which they proceeded to solve. To-day the stock of that company has a market value of about $140,000,000.

Jan 1, 1926

By R. A. Nemchek

ABSTRACT Concentrator plant design has evolved from large numbers of small grinding mills to small numbers of large mills. Consequently, plant performance often hinges on the productivity of a single large semi-autogenous grinding mill. Industry attempts to address the grinding mills’ critical nature frequently result in specifications that can be made simpler, more economical, and better focused on the project’s goals. This paper surveys current specification writing practices and proposes an improved approach recognizing that product design, procurement, manufacturing, and quality are interrelated in a successful project. The lessons learned here can apply to all types of machinery specifications.

Jan 1, 2014

By D. F. VanDine, H. George

"The possibility of spoil pile failure at the Kara Kara bauxite strip mine, Guyana, South America, is of major concern to the mine operators. The current mining technique requires the continuous operation of an 11 ms bucket capacity walking dragline on top of 18 metres of freshly spoiled uncompacted overburden material consisting of varying mixtures of kaolinitic clay and quartzitic sand. A field biased geotechnical study of undisturbed overburden and corresponding spoiled material has identified site-specific, non-linear correlations between vane shear strength, standard penetration resistance and spoil pile composition. Readily available geological exploration borehole logs has enabled a composite clay isopach map of the entire mining property to be drawn and critical areas to be zoned according to expected slope stability. Stability has been assessed using simple hand calculation techniques. Use of the resulting stability map provides the mine operators with a means of forecasting the need for appropriate preventative measures at varying stages of mine development, throughout the life of the mine.A similar investigation procedure could be employed at many presently operating and future strip mines.IntroductionThe Kara Kara bauxite stripe mine is located at Linden within the bauxite belt of Guyana in South America. The mining property covers a total area of 88 hectares of flat to gently sloping ground of which some forty per cent is being actively mined or being preparatorily stripped of overburden, prior to eventual mining (George and Gordon, 1979). The regional climate is tropic and humid. Temperatures vary from 16°C to 38°C and yearly rainfall averages 2600 mm, with at least 55 per cent of this precipitation occurring during the 'wet season' months of May to July and December to January."

Jan 1, 1983

By B. R. Richards, B. G. W. Robinson

"This paper shows how metal values can be profitably won from a comparatively small and remotely located but high-grade orebody. To do so is not uractical for a large mining company, with its necessarily high overhead of services and organization essential to a large producer.To evaluate, develop and profitably exploit a limited but defined ore deposit becomes only a problem of determining the dollars required to win the dollars available. This paper will record how this was carried out during 1965 and at the same time describe the history, development and production plant of this property."

Jan 1, 1966

By W. G. Scott

IT IS APPROPRIATE that your Institute should have chosen, for its 1956 Annual General Meeting, the Capital City of a province which is making such rapid advances in mining. The railway industry is proud to be playing an active role in this development, expenditures on equipment and railway construction in the Province of Quebec alone in recent years being in ?excess of a quarter of a billion dollars. In looking up some background material for this address I ran across a definition of a mine by Mark Twain, the great American humorist, which I thought might amuse you. He said that a mine was "a hole in the ground owned by a liar". I am sure that if he were alive to witness the enormous value attached to Canada's mineral resources today he would quickly change his definition. Canada's postwar record of mining development has been staggering in its variety and enormity. Historically, only the ?construction of our transcontinental rail ways outranks the largest of three of these development projects - the aluminum undertaking at Kitimat; the Quebec-Labrador iron ore deposits ; and the petroleum and natural gas developments in Wes tern Canada.

Jan 1, 1956

By B. I. Boyko

As part of the Ministry of the Environment's Resource Recovery Program, the Province of Ontario has constructed a $13 million "Experimental Plant for Resource Recovery" in Metropolitan Toronto. The technology and unit operations involved in the processing of municipal solid wastes at a rate of 40 tons per hour at this facility are reviewed. Shredding, air separation and classification, screening, magnetic separation and composting are some of the operations featured at this plant. Recoverable commodities expected include paper, ferrous metals, an air-classified light fraction (shredded paper and film plastic), glass and compost. Existing and potential markets for these materials are discussed.

Jan 1, 1978

By S P. Giambra

The 50,000-ton-per-day Concentrator and Crushing Plant, complete with its related water supply, tailings disposal and concentrate handling systems, was started up in a five-month period, with the entire plant obtaining its design capacity six months after the first mill became operational. Individual mill lines, with their spiral circuits, achieved design capacities within a week after the first treatment of ore through each mill. Construction and start-up proceeded together in many areas of the plant, and considerable organization and cooperation between the Owner, the Engineer and the Contractors permitted a smooth transition from construction to operation. PLANT DESCRIPTION THE Carol Lake Plant of the Iron Ore Company of Canada l1as been well described in various technical magazines. The purpose of this paper is to present a brief outline of the start-up of the con-centration complex. This start-up was accomplished in a period of five months, with the plant producing one million tons of concentrate and achieving its design-rated tonnage less than six months after the first ore was treated.

Jan 1, 1963

By L Thompson, R C. West, T S. Kho

In 1978, the Outotec direct to blister flash (DBF) smelting process was commercialized with the commissioning of the Glogow 2 smelting facility in Poland. Since then four further DBF facilities have been constructed, two at Olympic Dam, one in Zambia and most recently one at Glogow 1 in Poland. The DBF smelting process differs considerably from conventional smelting process in both chemistry and unit operations, presenting opportunities for flowsheet capital and operating cost savings particularly when the concentrate copper grade is high. WorleyParsons has amassed considerable expertise in the Direct to Blister process and in this paper the process is compared to the modern two stage Double Flash process. The processes are modeled, and the key operating parameters, consumables and production metrics are directly compared. Subsequent flowsheets, key equipment lists and capital costs are also presented for comparison and discussion. The results show the range of concentrates which are most economically treated by the DBF process relative to those best treated in conventional processes along with those concentrates which could be treated by either process. INTRODUCTION The Outotec Direct to Blister (DBF) process was developed and installed at Glogow in 1978 (Czernecki et al., 2006). Currently there are a total of five DBFs built on three sites: Glogow No.2, Olympic Dam No.1, Olympic Dam No.2, KCM Zambia and Glogow No.1, being the most recently constructed. The DBF process was the first flash furnace process to produce blister copper and paved the way for the subsequent development of the flash converter and other continuous converting processes. Today four flash converters are in operation taking the total number of flash furnaces producing blister copper to eight. In all DBF operations it is the unique ore and concentrate composition which made selection of the DBF process the most attractive. In all cases, the concentrate is relatively high in copper but low in iron because chalcopyrite is not the major constituent. When considering smelting options for high copper, low iron concentrates a key question is then often asked, “At what point does it become economic to switch from two stage smelting and converting process to the DBF process?”

Jan 1, 2019

By François Charette

High stress conditions in weak rock masses lead to large deformation and breakdown of the rock material, while stress release events in hard rock mines can lead to sudden and usually violent rock failure. Typical support systems combine various reinforcement and support mechanisms to provide the required convergence control and retainment, but results are often mitigated by failure of surface liners, shotcrete and tendons. The paper reviews differing requirements of support and reinforcement for different failure types. In addition, the mechanical performance of a new reinforcing tendon is presented and analysed in view of the field requirements. Field tests results are presented.

May 1, 2011

By C. C. Li

The D bolt is a new type of energy-absorbing rock support element recently developed in Nor-way. The D bolt is not only able to accommodate large rock deformations, but can also provide a load-bearing capacity as high as that of rebar bolts. Furthermore, the anchoring quality of the D bolt is similar to rebar bolts because of its multi-point anchoring design.

May 1, 2009

By B. Courtaud, L. Donati, V. Weigel

As a growing mining company, ERAMET is looking for new positions in the strategic metals market. In this context, the Gabonese Maboumine pyrochlore deposit is currently being studied for the recovery of niobium, tantalum, rare earths and uranium. This ore shows mineralogical and chemical characteristics that make it challenging to process by existing practices, from both technical and economic points of view. ERAMET has developed since 2008 an innovative hydrometallurgical process, which has been successfully operated at a pilot plant scale (more than 35 weeks in continuous). The upstream part of the process aims to dissolve valuable elements in sulphuric acid. The first step is dedicated to dissolve the ore matrix, leaving the pyrochlore unleached. The second step consists in chemically breaking down pyrochlores in order to form soluble species of the valuable elements. After dissolution, the valuable elements are separated into different flows: niobium and tantalum are recovered and transformed as commercial ferroniobium on one side, and rare earths and uranium remain in the solution to be recovered in the downstream part of the process. The main goal of this paper is to discuss the upstream part of the process, which has given successful results.

Jan 1, 2014

By Wei Yun-Jie

Columnar jointed basalt is a fractured rock, with a lot of small spacing structural planes and poor integrity of the rock mass. On the basis of the comprehensive study of the columnar shape of Columnar joints, rugosity of the fracture surface and the chemical composition of basalt, columnar joints of Bai hetan dam area were formed as a result of the cooling and shrinkage effect of magma. Columnar joints basalt are mainly chlorite, kaolinite, epidote, tremolite chemical reactions and the content of columnar joints are mainly chlorite by slice identification and chemical analysis. Columnar joints basalt showed high uniaxial tension test, low coefficient of friction and high cohesion by indoor physical and mechanical test. Columnar joints rock mass showed high strength and large deformation by field shear test and deformation test. Columnar joints basalt can be used directly as a foundation of dam as long as we follow the rules and reduce disturbance strictly.

May 1, 2009

By M. C. Bétournay, J. E. Udd

"The legacy of abandoned mines in Canada creates issues that impact on both the health and safety of Canadians and the environment. Solutions to the problems of abandoned minesites require a detailed understanding of site conditions, the engineering solutions which may be relevant, and planning for effective use of the land. In this paper, the authors outline the basic thrusts that have been developed at CANMET to address this problem. These include: multiprovincial agreements to develop a national database; methods of site rendering; a ten-year research program to develop engineering approaches; the review of a large number of case studies; and outlining the associated risks. Examples of the applications of this research are provided in the areas of: municipal, provincial, and federal co-operative projects; site-specific applications; and international linkages."

Jan 1, 1997

By K. H. Concannon, K. I. Hindle

"The use of simulation modeling in the primary metals industry (including mining, smelting, and metals processing) is expanding as significant cost-benefits can be realized by companies employing capital intensive processes. The economic scale and complexity of operations found in this industry is well-suited to applications using this ""what-if' computer modeling technique, ranging from proof-of-concept projects to testing facility design or configuration, and determining resource requirements. More recently this technique is being used to support on-going planning and scheduling for operations using the simulation as the engine to derive the best schedule. With increased computer processing capability, deterministic models are now being developed to capture the workings of a production system or conversion process, allowing real-time monitoring and scheduling of these operations. This paper presents a sample of some recent discrete-event simulation modeling applications that demonstrate the capability and benefits of this technique in the primary metals industry. These include the use of simulation to support the long-range planning of underground mining operations; the modeling of a metals supply chain network that employs a multi-modal distribution system; the scheduling of a metals coil finishing process using a deterministic simulation model; and a more detailed description of the use of simulation to model furnace and converter aisle activities within a smelter operation in Northern Canada."

Jan 1, 2007

By M. T. Ho, D. E. Wiley

The iron and steel industry accounts for almost 5 % of the total world CO2 emissions. Optimisation of the steelmaking process has led to significant reductions in the energy intensity to the point where it is now close to the thermodynamic limit. Further reductions are not likely to be achieved with efficiency improvement alone and will require the development of novel or breakthrough technologies. This paper will show the costs of implementing CO2 capture at direct atmospheric emission points for a number of iron and steel production processes. These include a conventional process, top gas recycling processes, the Corex and Hismelt smelt reduction processes and the Midrex direct reduction process. Depending on the point source emission, costs of capture with existing chemical absorption technology at iron and steel plants can be similar to capturing CO2 at pulverised coal fired power plants.

Jan 1, 2015

By C. V. Corless

1. Introductory Some members may recall that at the Annual Meeting two years ago I read a paper, 'The Future of the Mining Industry in Canada." Discussing this large subject it was possible only to outline the facts and inferences leading to ?the conclusion that Canada is a country endowed with enormous mineral wealth, of which the fringes are yet scarcely touched. In the present paper, I wish to examine in somewhat fuller detail the evidence, both direct and inferential, concerning the mineral wealth of the greatest physical and geological feature of Canada-the Precambrian Shield. Many, if not most, of these facts are already familiar to you. But, since they will form the basis of the reasoning employed, they will be recalled for explicit reference. First, let us review very briefly the position and extent of the Shield. The area of the entire Shield is given in textbooks as 2,000,000 square miles, of which perhaps 10 or 12 per cent. is exposed in the south-easterly part of Canada's Arctic islands. The remainder occupies roughly two-thirds of the North-west Territory; the north-east corner of Alberta; one-third of Saskatchewan ;two-thirds of Manitoba; three-fourths of Ontario; and nearly ninety-five per cent. of Quebec.

Jan 1, 1924

By Jan E. Nesset, L. Paul Staples

"High Gradient Magnetic Separation (HGMS) technology, although developed over 2 decades ago, has not been widely applied to the separation of sulphide minerals. Under conditions of strong magnetic field gradients, weakly magnetic minerals such as chalcopyrite (CuFeS2) and marmatite (Zn(Fe)S, sphalerite with iron in solid solution) behave paramagnetically and can be effectively separated from diamagnetic minerals such as galena (PbS). The application of this technology to the separation of Cu-Pb and Zn-Pb bearing streams in the treatment of fine grained complex sulphides may in some cases be more effective than separation by flotation. A 2 TPH Sala HGMS pilot plant was operated at Brunswick for a nine month period, ending in March 1995. The testing demonstrated the mechanical reliability of the technology, the consistency of operating results and the scale up from laboratory testing. HGMS is seen as a complimentary technology to flotation, best suited to performing those separations of galena (and other diamagnetics) which flotation does not do as well.IntroductionBackgroundSince the turn of the century, the magnetic character or magnetic susceptibilities of minerals have been determined with increasing precision and accuracy. Figure 1 illustrates specific magnetic susceptibilities of some common minerals. As long as susceptibility ranges do not overlap, separation is possible.In 1937, the principle of using a magnetizable matrix material in a magnetic field to increase both magnetic flux density gradients and number of capture sites for susceptible minerals was first applied (Frantz). It was not until the 1970's, however, that the genuine development of wet high gradient magnetic separation began with the introduction of very fine matrix materials to the magnetized volume of large solenoid magnets. Today, dozens of HGMS units purify, filter and separate minerals, primarily for the removal of iron stained minerals from clays used in the paper coating and china clay industries and for the recovery of fine titanium and iron oxides in the iron ore industry. Only the Garpenburg mill in Sweden is currently applying a continuous HGMS machine to separate complex sulphide minerals; upgrading a lead concentrate since 1988."

Jan 1, 1996

By The Staff

Introduction It is the purpose of this paper to discuss a number of the metallurgical improvements in the technology of copper-nickel ore treatment which have been introduced during recent years in the plants of ?the International Nickel Company of Canada, Limited. In common with other ore treatment processes, the procedure for extracting nickel and copper is changing almost continuous! y. These changes are necessitated by reason of changes in ore grades and characteristics, rising material and labour charges, and the constant drive to maximize metal recovery and to minimize production costs. It is not possible to present a comprehensive list of all the changes made, and only a selected number of the improvements in the milling, smelting, and refining operations are covered. It should be clearly understood that some phases of the procedures described have been pioneered by others in kindred fields and due acknowledgment is given to their foresight and efforts. Articles have been published over the years describing the operations of the International Nickel Company plants and the reader is referred to the Engineering and Mining Journal, Vol. 130, No. 9, November 10th, 1930, and to the Canadian Mining Journal, Vol. 58, No. 11, November, 1937, and Vol. 67, No. 5, May, 1946. Other references are the Transactions of this Institute, 1932, 1938, and 1946; Metals Technology, American Institute of Mining and Metallurgical Engineers, February, 1938, and Canadian Chemistry and Process Industries, April, 1940.

Jan 1, 1948