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By G. Beckstead, L. F. Sawatsky, R. Nutbrown, D. Long, G. Gould

"This paper presents a case study for optimizing water management at Gregg River Coal Mine located near Hinton, Alberta. The optimization study was derived based on a review and assessment of existing management practices and plans for future operation and final reclamation. A proactive water management strategy was developed to assist mine staff in adopting a rational, environmentally sound, and economical approach to water management. A plan was developed to provide for safe operation, self-sustaining operation, low maintenance, minimum negative environmental impacts, and anticipation of future needs for existing and future operations. A plan for final reclamation drainage was developed including establishment of effective, sustainable, and maintenance-free water management systems. The study demonstrated the importance and benefits of a proactive approach for integrated mine water management. This approach is recommended for other similar mine operations because it will improve environmental compliance and reduce costs of water management. IntroductionGregg River Resources Ltd. (GRRL) operates an open pit coal mine on the eastern slopes of the Rocky Mountains, located about 45 km south of Hinton, Alberta. GRRL opened the mine in 1982 and expects to continue operations after Year 2000. GRRL has progressively reclaimed the disturbed area and expects to complete mine-land reclamation shortly after mining in the area is complete. The existing disturbed area and reclaimed area covers approximately 9.5 km2 and will expand to about 10.5 km2 upon mine closure.Like other coal mines in the mountainous areas of Alberta and British Columbia, the GRRL coal mine is subject to highly variable temperatures and moisture conditions. Average monthly precipitation varies from a low of 12.6 mm in January to a high of 113.0 mm in August, based on the precipitation record at the mine site since 1982. Despite the relatively high rainfall during the spring and summer months, excess water problems during rainfall events are quickly replaced by water deficit conditions during periodic droughts. Surface runoff varies from near zero in the winter to a mean annual monthly maximum of 78 mm during the month of June. The mean annual surface water yield is 345 mm."

Jan 1, 1997

By E. C. Sanford

A laboratory-scale batch extraction unit and operating procedure for studying the hot-water separation of bitumen from Athabasca tar sands are described. The extractor evolved from earlier units and has been in use by Syncrude Research for the past 10 years. By using a unit such as this, it is possible to study tar sand feed quality and the effects of chemicals on the hot-water extraction process, while process variables are held constant. Data are presented to demonstrate the importance of surfactants to the process and the interrelated role of inorganic bases and surfactants.

Jan 1, 1979

By L. T. Loe, A. S. Norsk, Mo i. Rana

High production rate and good stability demand the optimization of all phases of electric pig iron smelting. This is important with respect to slag chemistry, which to a large extent regulates the process temperature in electric smelting. Controlled basicity and slag volume. and a satisfactory screen analysis of the reduction material and sinter, are of the utmost importance for smooth furnace operation. Large variations in slag volume and in B/ A and C/Fe ratio will have an influence on the furnace resistance and thus the specific energy development in the furnace, which lead to variable reduction of SiO.. The result will be variable hot -metal quality and un-stable furnace operation.

Jan 1, 1970

By Paul B. Batten

Shutdown is a generic term for what may be called an Outage, Turn Around (TAR) or Overhaul etc. Running a plant shutdown well has always been key to the financial contribution of a mine. However, something important has changed. The post pandemic reality is that it is harder to retain workers and many of those near retirement just didn’t come back to work. This is creating a shortage of experienced people and a workforce that changes employers easily. We are seeing the impact of this manifested in the erosion of established maintenance and supply chain processes that now struggle to yield the plant runtime that could once be taken for granted. The scope, cost and duration of a shutdown varies widely depending on the nature of the work and the equipment being renewed. The PM of an electric shovel might require a week of downtime and cost $100,000. A gold plant may need to go down for 3 days when its time to change mill liners and cost $500,000. A turnaround in a refinery can take more than a month and cost multi millions. Despite the huge differences.

Jan 1, 2023

By B. Chareyre, H. Pourpak, L. Scholtès, E. Papachristos

"Numerical methods used to study hydraulic fracturing in low permeability rock masses need to take into account the interaction between the progressive failure mechanism of the intact rock matrix and the pre-existing natural fractures. A fully coupled hydro-mechanical 3D discrete elements model dealing with such interaction is presented here. The ultimate objective is to grasp the role of the rock-matrix failure on the propagation of the main fluid driven fracture under different stress fields and pre-existing fracture orientations. The proposed method provides the spatiotemporal distribution of the induced crack events which can be tracked during the simulations, making possible the identification of the local mechanisms leading to macro-failure in the rock matrix or reactivation of the discontinuity planes. Fluid flow inside a fracture, pressurized crack and hydro-fracking experimental tests were simulated as part of the validation process of the model and, are presented in this paper.INTRODUCTIONWith the expansion of shale gas and geothermal reservoirs exploitation, the technique of Hydraulic Fracturing (HF) has been widely used over the past years (McClure, 2012; Britt, 2012). Despite recent advances in micro-seismicity analysis or numerical modeling (Nagel et al., 2013), the way progressive failure of rocks affects the fluid flow depending on the in situ stress conditions or the rock heterogeneities is not fully controlled yet (Zoback, 2010).In this work we focused on setting up a three-dimensional discrete elements model to study fluid driven fractures propagation. The intact rock is modeled by a discrete element method (DEM) able to reproduce fracture initiation and propagation (Scholtès and Donzé, 2013, Garcia et al., 2013). The pre-existing fractures are explicitly modeled and can be individually defined or be part of a discrete fracture network (DFN) (Harthong et al., 2012). Their mechanical response is fully coupled with the fluid within a HM-DEM framework. The fluid flow and it’s interaction with the intact matrix and the pre-existing discontinuities is modeled through a Pore-scale Finite Volume (PFV) scheme specially enhanced for fractured rock modeling (Chareyre et al., 2012, Catalano et al., 2014) ."

Jan 1, 2015

By Roorda H. J, R. R. Saddington, Curlook W

THE copper-nickel sulfide ore deposits of the International Nickel Company of Canada, Limited contain the minerals pyrrhotite, pentlandite, and chalcopyrite. In the extraction of the nickel, copper, and iron, much of the processing involves oxidation of the metals as well as sulfur. Roasting plays a predominant role at several stages in the operations which prepare the constituent metals for refining. Copper, nickel and iron concentrates of various grades, ranging from low-grade nickeliferous pyrrhotite to high-grade nickel sulfide, must be partially or completely oxidized. Figure 1 shows the main points at which roasting is conducted at INCO. Roasting experience at INCO dates back to the time when lump ore was partially roasted in heaps. It has progressed through single hearth roasters, sinter machines, multiple-hearth roasters, flash roasters, and more recently has centered on the development and utilization of fluid bed roasters. The primitive, slow, and inefficient method of heap

Jan 1, 1961

By W. H. S. McFarland

THE Yukon Consolidated Gold Corporation, Limited, a Canadian company, operates alluvial gold dredges in the Klondike goldfields of Yukon Territory. Its operations are of unique interest to Canadian mining as it is the only large-scale placer mining operation of this type in Canada. Its properties lie in the valley of the Klondike river and its tributaries, Bonanza, Hunker, Bear, Last Chance, and All Gold creeks, and in the valley of Indian river and its tributaries, Dominion, Gold Run, Sulphur, Eureka, Montana, and Quartz creeks. At the end of 1938, they consisted of 1,650 placer mining claims and 9 leases or concessions. They cover a belt with an area of approximately 1,000 square miles. This vast area covers in part claims which have been previously worked by other methods such as 'drift' and 'open-cut' mining, and areas which were too low grade for such methods. The ground held by the Company is not held in freehold but in the form of mining claims and mining leases granted by the Dominion Government under the provisions of the Yukon Placer Mining Act. Full-size creek claims are 500 feet in length by 1,000 feet on either side of the base-line. Hill and bench claims are 500 feet up and clown the valley and 1,000 feet at right angles to the valley. All claims are held on the basis of an annual renewal fee of $10 for each claim plus 'representation work' of an assessed value of $200 per claim per annum. For the purpose of such representation work, claims may be 'grouped'. This means that work done by one dredge is sufficient to 'represent' a comparatively large block of claims. It is only in this way that it becomes possible to consider operations on a large scale over a term of years, for such operations would obviously be impossible on law-grade ground if representation work had to be done separately on each individual claim in each year.

Jan 1, 1939

By Lachezar Tsotsorkov

Being a mining company, Assarel-Medet has a significant impact upon the environmental components. In order to meet the legal requirements and the requirements stipulated by the effective permits as well as to reduce the environmental imprint throughout the years, the policy of the company to implement a number of projects to improve the environmental components quality and the environmental state in the company?s region. The projects associated with atmospheric air quality management and reduction of the impact exercised by Assarel-Medet JSC by implementing various measures to eliminate the potential sources of the impact, preventive and rehabilitation initiatives as well as organizational and administrative activities are among the most important ones. A stable improvement of atmospheric air quality in the region and minimization of the company impact upon the ground air state in the region was observed in the period from 2005 to 2012 due to the applied measures. This project is a contribution to the environmental protection, in particular to atmospheric air protection, by applying integral monitoring and modeling methods to identify the negative impact by the mining companies and plan measures to reduce and restrict it as well as to improve the quality of the environment and living area of people working and living in the impact range as an element of sustainable development.

Aug 1, 2013

By D. E. Keeley

lntroduction Some years ago it was general practice in Canadian mines to use the best timber available, just as it was cut from the tree. Later, to prevent 'borers' from getting into the wood while stacked in the yard, the bark was peeled off, cleaned up carefully, and burned to eliminate a breeding ground for these and other destructive insects. This practice of good housekeeping also decreased the hazard from fire in scattered bark. A few years after damage by borers had been minimized, it became apparent that increased temperatures in the mines, occasioned by deepening operations, were being accompanied by rapid growth of fungus and by decay in timber underground, greatly shortening its life. In places on upper levels where the air temperature was below 50 deg. F., untreated timber retained a large proportion of its strength for ten or more years. In other places on these levels, however; its life was short and it developed much dry rot and merulius lacrymans. In these latter places and on lower levels in the mine where temperatures ranged from 50 to 60 deg. F., approximately, the wood became infested with extensive growths of this white fungus. This development was accompanied by the production of millions of spores. Spread of infection was due mainly to the transfer of spores from the warm lower levels to the cool upper horizons by upcasting ventilation currents. So serious did this become that about twenty years ago Lake Shore, Hollinger, and McIntyre Mines decided to investigate the use of wood preservatives and the plant necessary to treat timber.

Jan 1, 1949

By J. E. Nesset

Significant progress has been made over the past few years on characterizing and understanding the hydrodynamic properties of frothers and collectors and their effect on flotation performance. This new understanding of the relationship between chemistry and hydrodynamics has dramatic implications for how flotation circuits should be controlled and optimized. Previous work has shown that choosing a frother of the right 'strength' is critical to the optimization process, and the work and discussion presented here serve to strengthen the argument. In addition, we know that collector chemistry may also influence hydrodynamic properties and needs to be taken into consideration. To achieve the desired outcome, the overall system of reagents and operating parameters must be considered. This paper describes and discusses some of the findings from recent research on frother and collector chemistry effects (on hydrodynamics), and how this knowledge can be used to improve flotation performance. Examples from plant experience are discussed.

Jan 1, 2009

By B. Calver, D. J. M. Farnsworth

"As open-pit operations expanded at Pine Point, hydraulic aquifer evaluation was undertaken to establish the criteria necessary for the design of a feasible dewatering system.The extreme climate of this northern location dictated that the ore zone under extraction be rendered as dry as possible to minimize freezing effects. The design and implementation of such a system necessitated detailed hydraulic evaluation, and the problems that occurred are typical of those inherent in open-pit mining operations in northern areas.The paper describes the problem solution as approached from a mine engineering point of view, with particular reference to the practical aspects of operation and installation. The hydrological analysis used is simple and readily applicable to most open-pit dewatering problems."

Jan 1, 1969

By J. L. Miller, R. W. Burns

This paper sets out the various phases of bringing a merchant bar mill into operation from feasibility consideration through financing, design and scheduling to completion.

Jan 1, 1967

By M. P. Sinha, Rashmi, Tata Steel Ltd., S. Jaiswal, A. Bhatnagar, P. Garg

Reagents form a crucial part of flotation process as they have the power to control the surface properties of minerals. In case of coal flotation, collectors and frothers are two the important and commonly used reagents. But other types of reagents such as promoters, modifiers and depressants are also finding wide applications because of their availability to improve selectivity and increase recovery. Because of these chemicals the scenario has changed from flotation being used mostly for high rank hydrophobic coals to low rank, oxidised or inferior coals. In the present work a case is presented in which two non-ionic surfactants (abbreviated as A & B) known to act as emulsifier have been studied to get a better flotation performance for a preparation plant with varying feed characteristics. Laboratory flotation tests were conducted with both the surfactants using three feed samples of the plant by varying the dosage at three different levels. The highest combustible matter recovery (more than 80%) was obtained for surfactant B at a dosage of 75 ppm (parts per million) for feed 1. But at the same dosage the recovery decreased by 21% and 10.2 % respectively for feed 2 and 3. On the other hand surfactant A showed a consistent result for all the three feed samples giving the highest value at a dosage of 50 ppm followed by a decrease beyond this point. The tests were complemented by contact angle measurements that demonstrated the same trend. In addition to this the reproducibility of data for Surfactant A was checked and found that the standard deviations for both separation efficiency and combustible matter recovery were within the permissible range (less than 5%). Finally an in-plant process optimization study to evaluate the performance and applicability of surfactant A at industrial level was done and has been discussed.

Jan 1, 2016

By E. B. Wright

THE property of Falconbridge Nickel Mines, Limited, is in Falconbridge township, approximately thirteen miles northwest of Sudbury. From the mine and townsite, a gravel road leads to Sudbury and a branch line of the Canadian National railway to Sudbury Junction. The ore deposit is at the southeastern corner of the 'Sudbury Basin'. It lies in a sheet-like mass, striking in an east-west direction, between norite to the north and greenstone to the south. The general attitude of the ore-body is vertical, but with frequent variations in dip of as much as 10° to the north or south. The deposit is very irregular in outline, the width varying from a few feet to eighty or ninety feet. In the vertical plane, rolls are frequently encountered. Gouge is very often present at one or both ore contacts. The norite to the north shows much jointing. The chief ore minerals are pyrrhotite, pentlandite, and chalcopyrite. The nickel content of the ore is usually double the copper content, average assays ranging from 2 to 2.5 per cent nickel and 1 to 1.5 per cent copper. The ore is of three main types: massive, breccia, and disseminated. The breccia ore, the most common type, consists of sulphides containing rounded inclusions of highly-altered country rock, which, in places, are so large that sorting is necessary in the stopes. In the norite, the breccia ore may grade into disseminated sulphides, which frequently are sufficiently concentrated for profitable mining. In places in the breccia ore, concentrations of solid sulphide masses occur. Until early in 1935, all mining at Falconbridge was by shrinkage scoping, but this method was found to be less and less suitable as greater depth was attained. When mining had reached the 1,000-foot level, ore drawn from large shrinkage stopes was found to have been diluted as much as fifty per cent by sloughing of the wall-rocks, caused by increased rock pressure and insufficient support. It was apparent that this method of stoping was un-suitable and -Mr. E. J. Martin was engaged to superintend the introduction of a method of cut-and-fill stoping.

Jan 1, 1938

By D. T. Pritchard

"Introduction""No accounting system is very good, and all of them are infinitely variable*.”The purpose of this chapter is to discuss those facets of a typical accounting system which are most commonly encountered by operating managers in mineral processing plants. However, before concentrating in any detail on these it is important to understand the broad purposes and basic techniques of any accounting system in any major business.The three broad purposes of an Accounting System are:- Administering, controlling, and recording the flow of cash in and out of the business. Cash is, of course, converted into other assets (or stores of value) such as inventory, plant and equipment, etc. These assets also have to be administered, controlled and recorded.- Internal reporting to Management for information, for control, and for use in making business plans and decisions. - External reporting to stockholders, government, lenders and other outside parties.In this chapter we shall organize our discussion of accounting practice in mineral processing plants around these three purposes of accounting and focus in some detail on specific practices and techniques with which operating personnel will be routinely involved. This chapter is divided into the following: Accounting Basics; Administration, Control and Recording of Cash Flows; Internal Reporting; Planning and Budgeting; Cost Control; and External Reporting."

Jan 1, 1989

By Dong-Hyeun Koh, Yun-Soo Lee, Min-Seok Kim, Hyoung-Wook Kim

High strength AA7068 (Al - 7.88 wt.% Zn - 2.68 wt.% Mg - 2.07 wt.% Cu) aluminum alloy strip was successfully fabricated by horizontal-type twin roll casting. A simulation technique was used to obtain the range of casting conditions for fabricating strip without defects. The cast strip with thickness of about 5 mm was hot rolled, intermediate annealed, cold rolled to final thickness and subsequently annealed at various temperatures. Tensile properties of annealed and the aged specimens were evaluated at ambient temperature. Tensile strength and elongation of the annealed sheet are about 365 MPa and 28%, respectively. Also, the tensile and yield strength after the aging at paint baking condition (180 °C x 0.5 h) are 586 MPa and 551 MPa, respectively. Therefore, it is expected to show good formability prior to press or stamping and also provide high dent resistance after paint baking treatment.

Jan 1, 2015

By H. A. Pearse

The history of the flotation process, as applied to the practical field of ore dressing, dates back somewhat less than twenty years; yet this fact may be overlooked in view of the present universal dependence on this process in the concentration of almost all classes of ore. It is therefore interesting to recall that Britannia was the scene of some of the earliest experiments with flotation on a commercial scale. In 1911, sixteen years ago, an Elmore vacuum machine was operated for several months with encouraging results. In 1913, some time before flotation was very generally adopted elsewhere, a Minerals Separation plant, capable of treating 600 tons daily, was operating successfully at Britannia. Considering how little was known of the theory and practice of flotation at that time, the recovery was remarkably good, but it was not until the present mill was completed in 1923 that any attempt was made to raise the concentrate grade by differential flotation, or, in other words, to float the chalcopyrite while rejecting the then worthless pyrite with the tailings. The first ore passed through the present concentrator in March, 1923. As originally designed, the rated capacity was for 2,000-2,500 tons, but this has been increased year by year, until at the present time 4,000 tons daily can be treated economically. During the first few months of operation the concentrate grade averaged only 10-11 per cent Cu, but by the end of 1923 this had been raised to over 20 per cent, due to the elimination of the pyrite by differential flotation. In 1923 the tailings averaged approximately 0.25 per cent Cu, but also in the matter of recovery a considerable improvement has been effected, for during the year 1926 an average tailing of 0.15 per cent Cu was maintained.

Jan 1, 1927

By S. Foged

Umicore and MWH jointly demonstrated that mechanical dewatering of goethite and neutralised tailings significantly increased the life of a 30 ha tailings pond and improved the operation of the pond. Umicore operates one of its zinc production plants in Balen, Belgium. As part of its production process, an excess of neutralised and goethite¬containing tailings is generated. These have historically been stored inside large lined ponds. As the storage area of the current goethite pond was nearing its capacity, Umicore studied the potential for an extension to the existing embankment. However, this extension would face intense regulatory scrutiny, because the environmental and safety impacts were considered important. Together with Umicore, MWH suggested and investigated an alternative treatment approach consisting of mechanical dewatering prior to storage. A feasibility study was prepared where wet storage was compared to dry storage. Differences in safety risks, environmental impacts and economic costs were outlined. The study demonstrated that the life of the tailings pond could be increased from 6 to 22 years, seriously reducing the environmental impacts and safety risks at no significantly higher cost than would have been incurred with the continued operation of the existing pond. The results of the study are presented in this paper.

Jan 1, 2006

By John B. Hodgeson

AMMONIA is an essential constituent in the production of the ammonium-sulphate and ammonium-phosohate soil fertilizers manufactured by the Consolidated Mining and Smelting Company of Canada, Limited. The fertilizer plant, built in 1930 at Warfield, near Trail, provides a means of utilizing the large amount of sulphuric acid produced from the sulphur dioxide which is removed from the smelter smoke. The plant has an avail-able source of cheap power which makes the production of fertilizer economically possible. The fundamental operations involved in the production of ammonia at the Warfield plant are, first, the manufacture of hydrogen by the electrolytic dissociation of water; next, the recovery of nitrogen by the fractional distillation of liquid air; and finally, the combination of hydrogen and nitrogen in proper proportions and under suitable conditions to form ammonia.

Jan 1, 1938

By John A. Legge Jr.

"ACCOMPANYING Alberta's great natural endowments of oil, wheat, scenery, fishing, and hunting is also a generous endowment of geophysical problems to plague the interpreting geophysicist. These problems — by no means unique to Alberta — are sufficiently numerous and outstanding to be of major concern in exploration. Some of them have been adequately solved, others are well on their way to being solved, and still others remain almost completely unsolved. Often a problem readily solvable in one area can be solved only with great difficulty in another. Many are closely allied with the geological conditions and require the best co¬ordinated efforts of the geologist and geophysicist for their solution.It is a fairly general practice to study rather carefully the geophysical characteristics of known producing reefs in order to obtain data on which to base an interpretation of unproven areas. This practice obviously has a very sound basis, for, as discoveries become more and more widespread in the Alberta basin, it is found that the variation' in geological conditions has a marked effect on the seismic results, as would be expected. By carrying this analysis over an area it is possible more and more to anticipate the geophysical picture which should be obtained in connection with reefing under the varying geological conditions. Another phase of this procedure, and one that has received less attention, though it is certainly of importance, is the analysis of the all too numerous failures. A study of these failures may be more fruitful than a study of the successes for it may indicate weaknesses of field procedure, computations, or in¬terpretation not particularly obvious in the discovery areas. These studies must not only include the geophysical characteristics of the observed `anomalies', but should also be coupled with a thorough geological study to ascertain whether some unanticipated geological condition is responsible for the erroneous geophysical interpretation."

Jan 1, 1953