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By M. S. King

"A simple method is proposed for determining the long-term deformation behaviour of evaporites. The theory developed can be tested by measuring the change in diameter as a function of time of a vertical mine shaft opposite evaporite strata. Ultimate shaft closures predicted by the theory agree well with those calculated with the very much more complex theory of Serata (1968), provided that sufficiently high octahedral shear strengths are used in the former.An analysis of measurements made in an isolated opening in a Saskatchewan potash mine shows that the octahedral shear strength of the surrounding potash and halite was approximately 500 psi several years after the opening was mined. This value is less than that deter-mined experimentally for halite by Serata. The same data indicate, furthermore, that the in-situ octahedral shear strength is decreasing slowly with time.The current controversy regarding the actual deformation of evaporites will only be resolved by the cooperation of potash producing companies in releasing data on the long-term deformation of their mine shafts."

Jan 1, 1971

By C. Rodgers, E. (Ted) Warren

"LocationThe Key Lake operation of Cameco Corporation is located at latitude 57°N in northern Saskatchewan, within the southem boundary of the Athabasca formation. The nearest city is LaRonge, located 240 km to the south. Access to the mine is by all-weather road and by private airstrip.Description of OperationThe mill was designed to produce twelve million pounds of uranium oxide (U3O8) a year from a feed grade of 2.4% U3O8. Current production is fourteen million pounds from 2.0% feed.Following grinding, the uranium is leached using sulphuric acid and oxygen in autoclaves. An eight thickener counter current decantation (CCD) circuit is used to separate the uranium-bearing solution from the solid waste residue. The uranium in solution is further purified in a solvent extraction circuit. The purified uranium is then precipitated using ammonia, calcined at 840°C, and packaged in drums for shipping to refineries. There is a crystallization circuit to recover excess ammonium sulphate produced in the process, and a waste treatment circuit.HistoryUranerz Exploration and Mining discovered the Gaertner and Deilmann orebodies in 1975 and 1976, respectively. Between 1975 and 1977, Uranerz conducted laboratory studies and delineated a process for the Key Lake ore known as the ""Bonn process."" In 1977, Sherritt Gordon Mines Ltd. was retained to conduct further studies in cooperation with U ranerz. The technical feasibility of the Bonn process was generally confirmed. Howeve1~ alternative processing methods also appeared feasible, and over the period 1978-1979, a detailed research and development program was conducted to finalize the processes to be used and to provide data for design of the plant."

Jan 1, 2000

By D. Ling, Santos. R. M., T. Van Gerven, M. Guo

The valorization of alkaline waste materials from thermal processes utilizing intensified mineral carbonation routes is investigated. The principal advantages of this approach are the chemical stability and storage safety of mineral carbonates, the opportunities for process integration presented by the technology, and the potential for conversion of low-value materials into useful products. Treatment and disposal of steel slags are a costly burden on steel plants. Sustainable solutions for Argon Oxygen Decarbonisation (AOD) and Continuous Casting (CC) stainless steel slags and Basic Oxygen Furnace (BOF) steel slag are desired. An integrated on-site mineral carbonation approach is envisaged as a favourable solution.

Jan 1, 2011

By B. Lewis

Paper did not make deadline for printing

Jan 1, 1982

The Environmental Excellence in Exploration (E3) project is driven by the recognition that the minerals industry can only maintain its long term viability by ensuring its continued access to lands to explore for, and develop, new mines. Widespread implementation of sound environmental management practices by the exploration community and improved education and understanding of that by stakeholders will help substantially in accomplishing this, and E3 is designed to meet these needs. Exploration crews are now viewed as ambassadors for the global mining community. Their performance in managing the environmental aspects of an exploration program can demonstrate a commitment on the part of the international mining sector to environmentally responsible exploration and mining. We have all observed that failure to behave responsibly can alienate local residents, encourage anti-mining NGOs and jeopardize development. As the saying goes, ?you don?t get a second chance to make a first impression?, and we want to make a favourable first impression. The E3 project is focused on creating an electronic manual, the e-manual, which will provide rapid access to the most up-to-date information on environmental management practices for minerals exploration globally. The e-manual will reflect current thinking and practices in environmental management. It will be richly illustrated with actual examples that reflect the realities of exploration. It will strive to identify the key environmental issues and concerns that apply to most exploration projects, and identify other sources of relevant information useful to field practice. It is our belief that E3, or something very like it, is central to ensuring that the industry survives the current challenges to its viability. E3 will be a cornerstone of the mining industry?s drive to sustainability simply stated, if we are not permitted to explore for mines, there will be none of them at some point in the relatively near future.

May 1, 2002

By W. Swidzinski

"Zelazny Most" post-flotation copper mine tailings pond is the only place to of storeing wastes for KGHM POLSKA MI EDZ S.A. The flotation tailings is are the main waste stream in copper mining in Poland. Sufficient storage capacity for tailings is crucial for , thus uninterrupted production of copper is crucially related to the possibility of storing wastes in the pond. The pond covers a Its over 14 km2 arca, almost 50 m high dams making this dame this construction one of the largest in the world. The risk assessment of potential damage due to un stable ility loss of dams or environmental contamination, as well as safely constructing damsincrease of dams within the design criteriaprocess, require quick access to a large amount of the monitoring data , which in vast amount have to be monitored, that needs to be analyzed and processed and reported, every day. This In the paper describes the numerical information system "SyZeM" , used for designated to the "Zelazny Most" pond, baseding on the Oracle database and Geographical Information System , to manage the graphical and descriptive data in coherent way., is presented. The main structure of the system, as well as the methodology of storing, processing and reporting the geological, geotechnical, hydrogeological, geophysical, chemical and survey data are shown. The aspects of Optimizing optimal and risk mitigation and safe management of copper wastes and risk mitigation with the help of "SyZeM" are discussed.

Jan 1, 2007

By P. C. Lighthall, D. W. Zandee, W. Shukin

"IntroductionThis chapter deals with the on land disposal and storage of fine tailing in slurry form behind dams. Other types of tailing, such as coarse dry cobbs from magnetic separation of iron ores and other dry materials, have special problems and are not addressed in this paper. The disposal of mine waste is not included, except as such materials may be of value in the construction activities related to tailing disposal.In earlier North American mining, mines were smaller and frequently disposed of their tailing by direct discharge into neighbouring streams or bodies of water. Where that was not practical or not permitted, the solids were collected in tailing ponds and only the effluent liquids were released or decanted. The dams used for these early impoundments were fragile structures and failures were common. With the advent of large, low-grade open pit mines, and increasing awareness of environmental and safety considerations, recently established mines have carefully-designed tailing disposal systems, with wellconstructed dams and attention given to protection of the environment. Older mines are being improved or at least being examined critically with a view to upgrading as necessary to meet the new standards.Modern tailing disposal systems are highly variable and unique to each mine. Tailing pond selection and design is dependent on available topography as also is the design of transport and water reclaim systems. Suitable sites that are at higher elevations than the mills or distant from them may require that the tailings be pumped. Dams, either earth or rock structures built of the most convenient and economic material, are usually a suitable mix of local borrow, mine waste and coarse tailings. The most economic structures are those built mostly of coarse tailing."

Jan 1, 1989

By R. Flood

"Oil has been discovered off Newfoundland in a number of locations on the Grand Banks, the most notable and exciting being in 1979 when Hibernia was discovered. This discovery has brought new challenges to the province as well as to all of Canada. During the seven years"" since its discovery, both industry and governments have attempted to define its parameters and to find the most efficient and economical way to develop the field.A number of studies have been completed during the interval and in 1985, Mobil Canada Ltd. and partners stated that they would prefer to develop the field by using a concrete Gravity-Based Structure (GBS). IntroductionHibernia is located in an environmental climate much more severe than that of any previously developed oil field. The wind and wave conditions are similar to those of the North Sea, but unlike the North Sea, any structure on the Grand Banks would have to contend with ice floes and icebergs. Decisions had to be made on whether fixed structures could be put in place that would withstand the pressures of the ice and the impact of an iceberg, or whether structures that could be removed when such impacts were imminent would be used.Early studies in 1981, determined that it was possible to build a concrete Gravity-Based Structure which could withstand the impact of the largest icebergs that are anticipated to float in that area of the banks.Additional studies increased the knowledge of icebergs: their patterns and size, and verified the original conclusions that Concrete Gravity-Based platforms would provide a practical solution."

Jan 1, 1988

By P. Shibley, P. R. Clarke

Since this was an interim report of the initial operation of a long term project it is not available for publication. It is expected when the project is completed a full report of the work will be published.

Jan 1, 1968

By V. Bazhko, V. Yahorava

The calcium sulphate waste stream of the wet phosphoric acid process, commonly called phosphogypsum (PG), contains the majority of rare earth elements (REE) initially present in the apatite feedstock. Mainly light and middle REE are present in PG and their total concentration ranges from 0.27% to 0.35% by mass. Worldwide, around 7 billion tonnes of PG have been produced to date at a current growth rate of 150-200 million tonnes per annum. In total, an estimated 21 million tonnes of REE are locked in PG waste dumps around the world. Due to the value of the REE contained in PG dumps a number of processes have been devised for their recovery. The majority of these processes applied complete or partial gypsum dissolution, but were deemed not viable due to high capital and operating costs. Mintek developed an alternative method for the recovery of REE from PG by applying Resin-in-Leach (RIL) technology. This technology was tested on PG sampled from dumps and current arisings from South African phosphoric acid production plants. The extensive testwork program included evaluation of various lixiviants and optimisation of lixiviant additions, optimisation of REE leach and adsorption conditions, batch equilibrium and kinetic adsorption tests, continuous RIL testwork and numerous variability tests. It was found that PG from different sources was highly variable, both in terms of REE recovery as well as physical properties of the material such as viscosity and filterability of the slurry. The recovery of REE varied from 15% to 80% depending on the origin of the samples. A high-level economic study indicated that at a price of >21 $/kg for mixed REE oxide product in conjunction with an overall REE recovery as low as 15% the economics of REE recovery from PG via RIL technology may already be favourable.

Jan 1, 2016

By J. T. Vehkala, S. S. Kerr, D. E. Robertson

"Since the late 1970s, extensive work has been carried out at Placer Dome Inc. 's Dome Mine to develop new mining methods and equipment to improve the productivity of narrow vein mining (Mining Magazine, Oct. 1986, pp. 308-317; Mar. 1988, pp. 176-/79). This work has been focused on mining veintype deposits varying from 0.9 m to 1.5 m in width using open stoping and cut-and-fill mining methods.In 1989, the Dome Mine entered into a contract with Ram Raising Ltd., a joint venture company of Angus Martin and I.S. Redpath Ltd., to develop and mine a narrow vein test stope using an Alimak Raise Climber. Early results have been favourable, indicating that Alimak methods can be used successfully to mine narrow vein are.HistoryThe Dome Mine, which has been in continuous operation since 1910, is located in South Porcupine, part of the city of Timmins, Ontario. The mine is wholly-owned and operated by Placer Dome Inc. and is part of Placer Dome Inc.'s international stable of of 19 mines."

Jan 1, 1990

By R. S. Fitzpatrick, P. Hegarty

"Gravity separation is a key technology in the recovery of a range of mineral ores including coal, tin, tungsten and tantalum. One of the problems associated with gravity concentration is that recovery is traditionally lower than for other separation techniques such as the flotation of base metals. Any improvements in recovery will, therefore, have a significant effect on the economics of operations of this type. More accurate, robust modelling of gravity separators is one means of achieving greater recoveries. Furthermore, better modelling can lead to more informed equipment selection and process design for potential economic deposits.Previous models for gravity separation equipment have typically relied on simple metal mass balances from samples of the separated products. However, with advances in technology there is a ready availability of analytical instruments for the automated quantitative determination of mineralogy. Instruments such as the Mineral Liberation Analyser and QEMSCAN make it possible to estimate particle size and density (related to mineral liberation and association) which are the primary factors in gravity separation. Models produced using quantitative mineralogy of feed streams will be potentially superior to those produced historically.This paper describes test work undertaken on a wet shaking table using a synthetic ore. The objective of this test work was to develop a model to predict the effect of changes in feed ore characteristics on shaking table performance by measuring quantitatively the mineralogy of the feed material. Particles were divided into size/density classes based on the results of QEMSCAN analyses.It was found that it was possible to use data from QEMSCAN to predict the recovery of size/density classes and to predict the effect of changes in the relative abundances of these classes on the separation. This model can potentially be used to adjust operating variables to maximise grade and recovery by monitoring the input feed. Care was needed when utilising QEMSCAN data to ensure representivity."

Jan 1, 2016

By Yong Kang, Bingyuan Yan, Dandan Zheng, Xiaochuan Wang, Dengfeng Su, Dongyang Li

"According to the characteristics of rock mass and the directional cutting technology of water jet, a new idea of light shock controlled blasting with water jet slotting was put forward. Based on the fracture mechanics theory and the stress wave theory, the mechanism of damping with water jet slotting was analyzed. On the basis of the above, the evolution law of the pressure wave and displacement field during the blasting were simulated by FEM software ANSYS/LS-DYNA. The result shows that: the oriented slot plays a good role in orientation during the blasting, and makes the energy generated by gas released by the explosives gather at the tip of the oriented slot, which makes it easier for the main crack to expand along the oriented slot and indirectly reduce the stress effect on the protected object. Meanwhile, the energy of the seismic wave is reduced while transmitting through damping slot. Finally, compared with the normal blasting with damping ditch, the maximum acceleration is reduced by 15.62%, the maximum velocity is reduced by 52.99%, and the maximum displacement is reduced by 68.32%. INTRODUCTIONIn recent years, with increasing demand for energy and space, an increasing number of underground projects have been under construction. Drilling-blasting method, as a traditional main method for rock excavation, is still an indispensable means in the engineering construction. As is known, blasting vibration will cause the deformation and unstable of the existing building structures, so how to reduce the influence on the existing building structures caused by the blasting vibration has become the focus. Traditional shock absorption measures mainly include three kinds: the first one is pre-splitting blasting, the second measure is to change the parameter of explosive filling, and the last one is to excavate damping ditch between the protected object and blastholes. However, engineering practices show that: the protected rock may be damaged in the process of pre-splitting crack construction by blasting, the second measure is difficult in operating, and the third measure is troubled by large work quantity (Song Guangming, 1999; Lou Jianwu, 2004; Lou Jianwu, 2005; Li Xibing et al., 2008)."

Jan 1, 2015

By L. Rosato

In the past decade, as a result of increasing iron loads, Canadian Electrolytic Zinc (CEZinc) has become a pioneer in understanding the critical factors that affect the roasting of concentrates with high pyrite contents as well as those factors governing the effects of high iron loads on the leaching circuit. De-bottlenecking efforts in the roaster and acid plant section of CEZinc have given rise to a better appreciation of the impact of iron on roaster productivity. High standards for impure solution quality, zinc recoveries and residue disposal have all led to an increased comprehension of the limits of the leaching circuit and the optimization potentials with respect to iron and ferrites. In this paper, the impact of iron on the roasting and leaching circuits of CEZinc will be reviewed and special emphasis will be given to some of the more recent process optimization and improvement activities.

Jan 1, 2006

By L. G. Morrell

Introduction A Self-Dumping cage which combines the features of a small skip and a cage has been used in a vertical winze between the 2,000 and 2,500 levels at the Coniaurum mine for the past three years, during which time its success has been demonstrated by uninterrupted service and low maintenance charges. lt was designed by John Reddington, mine manager, and was built under his supervision in the Coniaurum mine shops. Being new in many of its operating features, a small-scale model was made and tried before the final construction was undertaken. The mechanical performance of the model suggested a few minor changes that were incorporated in the final drawings. During its three years of use, the automatic dumping device has saved the expense of deck-handling of the cars. This actually represents a gross economy of something over four times the cost of construction and installation, which totalled $1,325. The cage, empty, weighs 2,200 pounds, of which 500 pounds represents the weight of the dumping accessory and necessarily heavier construction. Besides a considerable financial saving, the time saved in unloading increases the daily hoisting capacity of the winze. In raising ore from the 2,500 level, five minutes are required for a complete trip. Allowing one minute for the alternative of decking, we believe that the automatic dumping has increased the capacity of the winze hoist nearly 20 percent.

Jan 1, 1933

By D. Brossman

"The virtue of spray drying is that it is a drying method, and so far the only one by which it is possible in one operation to divide a mineral concentrate into its basic primary particles.,In so doing, each particle gets the same treatment and the result is a dry concentrate more homogeneous than any other known concentrate drying process. This is particularly good for a flash furnace requiring a bone dry finely divided feed. The spray dryer also features a very short residence time and due to the very quick operation the solids are kept cool thus preventing any risk of fire or explosions on these pyrophoric materials.There are many spray dryers now in operation in the mining industry and one of the latest applications is in South Africa where a spray dryer is treating a copper-nickel platinum concentrate which is, after drying, fed toan electric arc furnace. Experience has shown that the concentrate should contain 4% moisture for the furnace, and this is achieved by drying the concentrate bone dry and then back-mixing with thickener underflow pulp to provide an extremely homogeneous feed to the smelter. As mentioned before, mixing with pulp would be more of an advantage because we would not be evaporating water which would have to be added again afterwards.One of the first spray dryers to go in was at Western Mining Corporation in Kambalda in Western Australia. (A series of slides was then shown)."

Jan 1, 1972

By H. Hamza

Efficient and effective management of extraction process tailings is an essential ingredient for the continued success and development of Alberta's vast oil sands resources. Open-pit oil sands operations north of Fort McMurray recover bitumen from flotation circuits. Process tailings are managed in carefully engineered and monitored external tailings management facilities and in below-grade mine pits. In order to support reduction of production costs and improve upon established tailings management practices, CANMET has been working with the oil sands industry in a collaborative framework to assess the potential to integrate thickened tailings into oil sands extraction process flowsheets. Albian Sands has commercialized the process while others, including Syncrude Canada Ltd., continue to evaluate the suitability of the process for their operations. This paper provides an update on R&D work undertaken in recent years to assess and develop the potential of thickened tailings technology for the open-pit oil sands operators of northern Alberta. The aim of this work was to explore opportunities to optimize process efficiency and environmental sustainability by improving water and energy conservation and develop more alternatives for tailings management and reclamation.

Jan 1, 2004

By Gang Mei, Nengxiong Xu, Yanlin Zhang

After open-pit mining finishes, an iron mine with steeply inclined ore-bodies will generally transform to underground mining. Non-pillar sublevel caving method, with horizontal slice mining from up to down, is commonly used for mining deep ore-bodies under the open-pit bottom. As horizontal slice mining proceeds, a gradually enlarging goaf will be formed under the open-pit bottom, the rocks surrounding the handing and heading sides of the goaf will collapse continuously, and then these results in rock-mass failure with large deformation and displacement in the open-pit slope. Based on FLAC3D, a modeling approach to predict pit slope deformation and failure induced by transitioning open-pit to underground mining is proposed in this paper. This method mainly consists of three procedures of modeling, i.e., mining modeling, landslide modeling, and filling modeling, of which landslide modeling is the core of the proposed approach. In the procedures of modeling with FLAC3D, iteration non-convergence is taken as a local failure criterion of pit slope. When iteration calculation cannot converge, the sliding modeling will start by deleting some elements with large displacements, and finish until convergence. Before modeling landslide, several displacement contours of rock-masses in the pit slope are searched out, and each contour is an approximate possible sliding surface of the open-pit slope. From these contours, the most proper one is selected as the slope sliding surface by using the iteration calculation convergence and minimum element deletion as the judgment condition. Landslide modeling is then realized by removing the elements outside the slope sliding surface. Finally, to demonstrate the effectiveness, the proposed approach is used to simulate the process of open-pit to underground mining at Yanqianshan Iron Mine, and to predict the deformation and failure characteristics of open-pit slope during underground mining. The case study results show that: the prediction of the slope stability determined by using our method is consistent with that calculated by using the limit equilibrium methods.

Jan 1, 2015

By F. E. Lathe

The method of feeding blast-furnaces to be described below is simply the application of well-known principles, and an attempt to carry that application to its logical conclusion. It does not involve radical changes in equipment, nor does it require unusual skill on the part of the furnaceman. In fact, much of its value lies in its very simplicity. Before giving details of the method it will be well to consider briefly the conditions under which it was used at the Nickelton plant of the British America Nickel Corporation, in the Sudbury district, before that plant closed down. The Sudbury nickel ore consists chiefly of pentlandite, chalcopyrite and pyrrhotite in a gangue of norite or greenstone. The proportions of sulphide and gangue vary widely in different mines, the former constituting about 45 per cent of the total in the British America sorted ore. The gangue is fairly uniform in analysis, carrying about 55 per cent Si02, 18 per cent A120 3, 13 per cent FeO and smaller quantities of CaO, MgO, Na20 and K20. The ore has been frequently described as refractory, a word which seems suitable when one considers the many unsuccessful attempts to smelt it pyritically, as well as the high percentage of coke normally used at all the plants in the district.

Jan 1, 1925

By Douglas A. Sloan

AN INCENTIVE or bonus system of payment is commonly used for mine labour. The incentive rates are usually based on the variable units of production, such as dollars per foot of drift advance or cents per ton of ore broken. Portions of the work that must be done to achieve the units of ?production are independent of the production unit and tend to be fixed work for the shift or for the job, irrespective of the production achieved. This fixed work has considerable influence on the equity of incentive rates. The effect of fixed work is to accelerate the loosening or tightening of rates if the production task is over-achieved or under-achieved, and of increasing the loosening of rates loosely set and the tightening of rates tightly set. This gearing of mine contract rates is the reason why changes in conditions, materials, equipment, or methods will change the incentive earnings to a greater degree than would normally be expected. Obviously, therefore, care should be taken in the setting of the task for incentive rates as the gearing makes an inequitable rate even more inequitable.

Jan 1, 1958