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By J. E. Danoczi

Shore Gold Inc. (Shore) is presently designing a diamond processing plant for the Star and the Orion South kimberlite deposits in the Fort à la Corne (FalC) area in central Saskatchewan. The first step in the plant is diamond liberation and occurs in the comminution section. Diamond liberation is the process of breaking up the kimberlite rock, as gently as possible so as not to damage the diamonds. Autogenous grinding mills (AG mills) use a combination of impact crushing, abrasion and attrition to break up the kimberlite. The forces that occur during the actions of abrasion and attrition cause the kimberlites to break up preferentially along lines of weaknesses which offers a ?diamond friendly? method of comminution. Hard competent kimberlite is commonly found in the diatreme zone as well as the root zone of the volcanic pipe and is the source of kimberlite for most of the Southern African diamond mines. Softer kimberlite is typically found in and around the crater area of a volcanic pipe and it is this kimberlite that makes up the majority of kimberlite for both the Star and Orion South deposits. These softer kimberlites can be readily broken up using abrasion and attrition imparted by AG mills. In order for Shore to benefit from the softer kimberlite found in the Star - Orion South diamond project, two large (10.97 m diameter x 7.10 m long) AG mills were designed for the comminution section based on extensive test work and simulations by Metso Minerals (Metso).

Jan 1, 2012

By Dave Tahija

"Many investigations are being performed with the goal of removing carbon dioxide from the atmosphere and permanently storing it in geologically stable settings. At the same time, carbon dioxide in the form of dissolved carbonate is steadily accumulating in the world's oceans. Both carbon dioxide sequestration and oceanic accumulation are constrained by the aqueous thermodynamics of the carbonate system. These constraints are illustrated using the STABCAL computer model to generate potential-pH and aqueous distribution diagrams of seawater in contact with various pressures of carbon dioxide gas. STABCAL diagrams and titration simulations are also used to model some potentially useful cation-carbonate sequestrationsystems.IntroductionAtmospheric carbon dioxide concentrations have risen dramatically in the past couple of centuries and are rising still, primarily as a result of human activities, especially the burning of fossil fuels. Increased atmospheric carbon dioxide concentrations have been implicated as a main cause of global warming but have other effects as well.Rising levels of atmospheric carbon dioxide result in increased concentrations of dissolved carbonate complexes in water, including the oceans. These dissolved carbonates interact with other dissolved substances, altering overall seawater chemistry, most noticeably causing lowered pH levels.Some of these chemical changes are observed directly, for instance the general drop in oceanic pH, [1], while others can be inferred and predicted using thermodynamic modeling. The chemistry of dissolved carbonate in seawater is not especially intricate, as such chemical systems go, but neither is it simple enough to be worked out on the back of an envelope. Interactions between the several simple carbonate species and all the major dissolved cations in seawater should be considered, as well as the effects of competing anions, especially chloride and sulphate, since they are much more abundant than carbonate in seawater."

Jan 1, 2011

By R. Karl Zipf, Suresh Bhatt

Highwall mining is an important coal mining method. It appears that upwards of 60 highwall miners are presently in operation, and they may account for approximately 4% of total U.S. coal production. A review of the Mines Safety and Health Administration (MSHA) data over the 20 year period from 1983 to 2002 identified 9 fatalities attributable to auger and highwall mining of which inadequate ground control accounted for 1/3. In the past 5 years, 1 fatality occurred in highwall mining. Estimates of the manpower requirements in highwall mining suggest that its fatality rate is essentially the same as for surface coal mining, thus highwall mining appears to be a very safe modern mining method. Highwall stability is the major ground control related safety concern, and operators are required to develop and follow an appropriate highwall mining ground control plan. The plans usually specify the following geotechnical parameters: hole width, maximum hole depth, maximum overburden depth, seam thickness, web pillar width, barrier pillar width and number of holes between barriers. Calculated web pillar stability factor exceeded 1.3 for most designs evaluated. This study examined records from 5,289 highwall miner holes with a total completed footage of about 2,560,000 feet to understand the reasons for early pull out. Average lost footage is typically about 20% of planned footage. Only 35% of the holes reached planned depth, and 20% were short due to rockfalls. Water and adverse geology accounted for 15% of the losses. Mechanical/electrical problems, guidance, and slope stability problems accounted for the remaining 30%. Web pillar stability factor for these holes also exceeded 1.3 in 95% of cases. Best practices to avoid trapped miners include: avoid mining in stream valleys, avoid mining near outside corners, careful alignment of each hole and the use of an onboard guidance system. Several issues in highwall mining ground control require further investigation including highwall mining through old auger workings, highwall mining near old underground mines, multiple-seam and multiple lift highwall mining and finally the size and frequency of barrier pillars.

By R. Barbaroux, B. Dubreuil, D. Lemieux, K. Nasrallah, G. Garcia Curiel

"As conventional, base or precious metal ores are being depleted worldwide, the mining industry is being faced with an increasing exploitation of arsenical sulfidic ores. Enargite is a common example. The downstream processing of these ores poses several problems ranging from high smelter penalties to finding economical and environmentally acceptable means of disposing of the arsenic. Several hydrometallurgical processes have been proposed for extracting arsenic from enargite concentrates, notably using alkaline sulphide leaching (ASL). However, few alternatives exist for removing the arsenic from solution and stabilizing it in an approach that is both economical and environmentally acceptable.Dundee Sustainable Technologies (“DST”) has developed a technology for the sequestration of arsenic by vitrification. Originally optimized to cost-effectively stabilize arsenic trioxide (As2O3), DST has shown that vitrification could be successfully extended to the stabilization of other arsenical products, such as calcium arsenate (Ca3(AsO4)2) and sodium arsenate (Na3AsO4). In this paper, the vitrification of arsenic in the context of an enargite leaching was newly explored and demonstrated successfully.Two processing routes are being proposed by DST for the removal of arsenic from enargite concentrates and their stabilization by vitrification. In one route, arsenic is extracted by ASL and is then precipitated under atmospheric conditions and with minimal use of reagents and time. The resulting precipitate is an unstable hydrated ferric arsenate (FeAsO4•2H2O) that is then vitrified in a non-dilutive method, significantly increasing the stability of arsenic and meeting the TCLP guideline. Unlike is required for scorodite, stabilization was successfully achieved without concern for the crystallinity of the precipitate."

Jan 1, 2017

By Oliver Bowles

ASBESTOS is a name applied to a group of naturally fibrous minerals. As indicated in a later section devoted to a detailed discussion of the early history of asbestos, the tern may be defined as a. fibrous form of serpentine or amphibole. It does not include fibrous forms of other minerals, such as wollastonite, nemalite (fibrous brucite), or the fibrous forms of calcite or gypsum. A material that has the characteristics of silk or cotton and at the same time will not burn is unique. Because it combines these qualities with other advantageous properties, asbestos has specialized uses for which no substitutes are yet available. Asbestos furnishes a major raw material for a great variety of essential products and their manufacture constitutes a vast industry. The United States leads all countries in the manufacture of asbestos products. The value of such commodities manufactured in 1952 exceeded $332 million. They are not only of vast importance to budding construction and industry but axe absolutely, essential to certain important fields of use, for example, steam packings and friction materials, such as brake-band linings on automobiles.

Jan 1, 1955

The Illawarra District, from 50 to 100 miles south of Sydney, is one of the State's important coalfields. It extends from Clifton on the north, to the Shoalhaven river on the south, and from the coast westward beyond the coastal scarp.For descriptive purposes, this area falls naturally into two zones:(a) the coastal belt backed-by the eastern edge of the plateau;(b) the plateau, westerly from the coastal scarp.(a) The Coastal Belt.A triangular shaped area extending from Clifton to the Shoalhaven river, composed for the most part of soft coal measures strata of Permian age, which, on weathering, undermines the massive overlying Mesozoic sandstones and causes the gradual recession of thecliffs.South of Wollongong, upper marine sediments and contemporaneous igneous rocks make their appearance beneath the coal measure beds and occupy the greater portion of the coastal belt.(b) Plateau Area.Extending westerly from the coastal escarpment is a plateau known as the Robertson Tableland, composed of Triassic sandstone and shales dipping gently in a northerly direction, and capped in places by Wianamatta. shales and r.rertiary basalts. This tableland is approximately 2400 feet above sea level in the vicinity of Robertson, and gradually falls to about 750 feet at Waterfall.The plateau area for the most part is highly dissected, rough, steep gorges alternate with sharp ridges.A large part of the northern watershed of the Robertson tableland is a reserve for Sydney water supply, and large dams have been constructed at Cataract, Avon, Burke, and Cordeaux.

Jan 1, 1938

By M. S. Badollet

"The study of the physical properties of asbestos minerals requires a careful isolation of the fiber from the wall rock and, at a later stage, a comparison of these physical properties with those of fibers that have passed through the milling and beneficiation processes.The effects of mineral impurities, loss of fiber length and the formation of extreme fines (asbestic and/or associated minerals) often show up in the formation of special asbestos products as well as in the commercial production of asbestos papers, mill-boards, asbestos cement products, plastics and insulation materials, and in the filtration of blood plasma and wines.Numerous test methods have been developed in Canada and in England for use in the asbestos industry. Special treatments of asbestos fibers have been used to improve their physical and chemical properties and to eliminate impurities.Numerous problems connected with the use of asbestos fibers are discussed, such as the effects of asbestos on filtration, surface area, surface treatments using organic or inorganic materials, the surface charge on the fiber, the presence of magnetite and air pollution elimination. Biological studies on finely ground asbestos, when dispersed in 0.9 per cent sodium chloride solution and then sterilized and injected into hamsters, show that by reducing the dose, the tissue damage can be largely avoided. In these experiments, Arizona asbestos fibers were carefully extracted from the wall rock, finely ground, and examined chemically and micros-copically for any mineral impurities that might be present so that any effect on the hamsters would be directly due to the presence of the asbestos. The harsh Arizona fiber induced more extensive tissue response than the soft fiber when tested in hamsters."

Jan 1, 1969

Auger operations produced 14 million tons of coal in 1974, or approximately 5% of all surface mined coal. It was the most efficient of all coal mining methods, producing 40.0 tons per man-day. Exhibit 1.1 gives a breakdown of productivity of all coal mining methods. Exhibit 161 PRODUCTIVITY OF COAL MINING METHODS (Short tons per man-day) [Method - 1971 1972 1973 1974 Conventional 11.00 10.00 9.75 9.30 Continuous 13.00 12.50 12.25 11.90 Strip Mines 35.69 35.95 36.00 36.00 Auger Mines 39.00 43.00 45.33 40.00 ] Unlike other surface mining methods, augering produces clean coal, largely uncontaminated by foreign materials, other than those existing in the coal seam itself. However, compared to other methods, the coal recovery rate is relatively low. For example, a triple-headed auger in a 35-inch seam would recover approximately 50% of the coal in the seam as compared to a 90 to 95% recovery rate for strip mining and a 55 to 65% recovery rate for deep-mining. The low auger recovery rate is due to the circular cuts and pillars left in the seam.

Jan 1, 1975

By Thomas Hyatt, Brandon Phetteplace, Camilo Alvarez

A test pile program was undertaken at a project site in Ain Sukhna, Egypt for an import/export oil jetty. Two 1219 mm diameter open ended steel pipe piles were evaluated at two separate test locations. Each test pile was dynamically tested during initial drive utilizing a Pile Driving Analyzer (PDA). Restrike testing was also performed to evaluate the time dependent soil setup. One static compression test and one static tension test was performed at each test location. A correlation of the static and dynamic load test results was established to develop a driving criteria for the piling across the two kilometer project. The constructability benefits of shorter piles will be discussed in more detail, given that the pile lengths were shortened by 9 to 10 meters on average. Lastly, the use of a four pile linear layout to perform both compression and tension tests will be covered. INTRODUCTION With the increased number of Very Large Crude Carriers (VLCC) & Ultra Large Crude Carriers (ULCC) being used to transport oil products around the world, companies and/or nations are presented with the challenge of transferring these products to and from the carriers in deep water scenarios, typically 15 to 20 meter depths, to accommodate the vessels draft. One option for loading/unloading the oil products from a VLCC or ULCC would be to transfer to/from smaller vessels several miles offshore, whereas the most economical option is to unload directly to a pipeline via a berth/jetty platform near shore. These berth platforms must be designed to withstand multiple loading scenarios while these carriers are moored and transferring their products. The use of Large Diameter Open Ended Pipes (LDOEP) piles are a common foundation choice for this offshore application. One of the drawbacks of LDOEP piles, especially across a large project site, is that there can be extreme variability in the pile driving behavior. This can be caused by either a change in soil conditions or the performance of the soil plug. Due to this variability, it is important to verify throughout the duration of the project that the piling is being installed to the correct criteria as established during the load test program. A well designed driven pile load test program, preferably with the combination of Static Load Testing (SLT) and Pile Driving Analysis (PDA), should develop a driving criteria that can allow the contractor and owner to monitor any change in driving behavior.

Jan 1, 2019

By L. T. Pasiechnyk

After a brief review of the various hydrocarbon storage methods currently being utilized and statistics on underground hydrocarbon storage, this paper will briefly describe the technology involved in solution mining salt to create caverns of engineered shape and size and briefly discuss the economical and environmental advantages of hydrocarbon storage in solution-mined salt caverns. Other possible uses of salt caverns will be mentioned.

Jan 1, 1978

By G Baiden

The removal of rock blockages in mining operations has long been a risky undertaking, especially in high overhead conditions. Moreover, the assessment of where to put charges and the placement of them has been difficult due to the lack of visibility and safe access to the area. Traditionally, wedging long poles with explosives on them to keep the operator at a relatively safe distance has been the tried and true method of attempting to remove the blockages. Unfortunately, this is not a perfect system as it usually takes several attempts to remove the blockage. Each successive attempt results in even more dangerous conditions for workers and/or damage to the mine due to the successively larger amounts of explosives used until the hang-up finally comes down.Over the years, different ideas have been proposed to improve this process and reduce the inherent safety risks. Some of the technologies that have been trialled include projectiles fired at the hang-up; large, cumbersome arms; and massive amounts of explosives, each of which come with their own inherent safety risks that result in dangerous situations for miners and the mine.After gaining a thorough understanding of the process, Penguin Automated Systems Inc has developed a robotic system that is capable of working in a rock blockage safely. The idea combines the latest in telerobotics technology with 3D scanning and underground geospatial positioning. The hang-up removal is performed by scanning the inside of the hang-up to rapidly develop a geospatially placed 3D model for the operator to use. The 3D model is detailed enough that the operator can attempt to pick the ‘keystone’. A blasting engineer or the operator can then determine the exact position where the explosive charge should be placed in the 3D model and thus at the actual hang-up. The operator, controlling the robotic arm, uses the 3D virtual reality model of the robot system and the actual drawpoint information model to display the location information, the arm can then reach into the hang-up to position the charge using the kinematic model of the robot system. The 3D model is used to provide views inside the hang-up so that the operator can move the arm safely and precisely. This process allows the operator to place the charge (using the 3D representation of the drawpoint) from a long distance away. As the process continues, the end of the arm drills the rock and precisely loads the explosives. The robot then returns the blasting cable to the command station, which is located in a truck at a safe distance from the blockage.This paper will review the development of the system and present the results to date.CITATION:Baiden, G, 2016. Robotic hang-up assessment and removal of rock blockages in mining operations using virtual reality for safety, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 745–754 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By J. E. Gillespie

Introduction Mineral wool may be defined as "rock, slag, or glass fibres made by a process of melting and blowing by steam or air, containing a minimum of oil and unfiberized material" (U.S. Bureau of Standards CS 117-44). The earliest production of the material was in Wales, about one hundred years ago. In the United States, the industry daces from 1870 when a plant, using slag as raw material, was established in Greenfield, New Jersey. It was not until 1897, however, that large-scale production was commenced on this continent at a plant in Alexandria, Indiana, which utilized rock from nearby deposits. Today, mineral wool is manufactured in many parts of the United States and Canada, the plants for the most part being in close proximity to deposits of suitable rock or to sources of slag. In the United States there are some seventy-five producers with a total annual capacity of nearly one million tons of wool. In Canada, in 1946, eleven manufacturers produced about fifty million square feet of batt-type mineral wool insulation material. Mineral wool is, perhaps, the most efficient of all heat-insulating materials and, moreover, it is fireproof, extremely durable, and insect- proof. Its high efficiency is due to the very low thermal conductivity of the fibres themselves and to the fact that the produce as marketed contains up to 90 per cent non-conducting air space. Depending on the degree of compression of the fibres in the manufactured product, the specific gravity ranges from 2 lb. to 10 lb. per cubic foot. Products Marketed Following are the principal forms in which mineral wool is marketed: Blanket. - Mineral wool with or without reinforcing on one or both sides, with various types of confining media, all suitably bound together.

Jan 1, 1948

By C. S. Gibson

"MOST of the mines in the Province of Ontario in Canada are multi-level operations in steeply dipping veins; yet there is an appreciable number whose de-posits are relatively flat-lying, ranging up to 45° inclination.The veins vary in width up to several hundred feet and may or may not be branching systems. The depths of mines range from a few hundred to 8,000 feet, approximately. The primary products of the underground group are asbestos, gold, silver, cobalt, copper, nickel, iron, uranium, talc, fluorspar, gyp-sum and salt.There are a few open-pit mines. The majority are temporary in type because, as the outcrops are removed, mining is continued be-low surface. Primary products of the open pits are copper, nickel, iron, magnesium and nepheline syenite.The industry as a whole employs about 50,000 persons, approximately 60 per •cent of whom have dust-exposure occupations. The definition of a dust-exposure occupation and the requirements for •dealing with same are set forth in The Mining Act of Ontario.Results of extensive and continuing studies on the incidence and progression of silicosis have been reported periodically for years past, in annual reports of the Mines Accident Prevention Association of Ontario and in papers presented at Conferences sponsored by Mcintyre Research Foundation of Toronto, all of which have been published. The information provided therein proves the effectiveness of the means being used to prevent silicosis and allied disorders."

Jan 1, 1960

This Bureau of Mines report and its companion report (Information Circular 9143) have been prepared to assist in the preparation of prefeasibility type estimates for capital and operating costs of mining of various types of mineral occurrences using current technology. The handbook provides a convenient costing procedure based on the summation of the casts for the unit processes required in any particular mining or mineral processing operation. The costing handbook consists of a series of costing sections, each corresponding to a specific mining unit process. Contained within each section is the methodology to estimate either the capital or operating cost for that unit process. The unit process sections may be used to generate, in January 1984 dollars, costs through the use of either costing curves or formulae representing the prevailing technology. Coverage for surface mining includes dredging, quarrying, strip mining, and open pit mining. The underground mining includes individual development sections for drifting, raising, shaft sinking, stope development, various mining methods, underground mine haulage, general plant, and underground mine administrative cost. This system can be used for estimating cost data for an undeveloped deposit or for checking or verifying mining costs from a developed deposit, with a minimum amount of background information.

Jan 1, 1987

I once read an æarticleÆ in FHM Magazine entitled æThe Coolest Jobs There Ever WasÆ. It was about a group of guys who were pursuing careers that any person on the planet would just kill for. I distinctly remember drooling over the pages, thinking how much I would love to be Michael SchumacherÆs Chief Engineer at Ferrari, or the Principal Designer and Tester for one of the big Dutch rollercoaster companies. From that moment on, I decided that I wanted a career that was cool enough to make it into the pages of that article. Throughout my time at university, I always had that article in the back of my mind. As a result I constantly wondered about what sort of job I could end up with once I left university. More importantly, I wondered if FHM would be banging down my door to put me in the magazine! After a long and stressful job hunting process (in between completing a thesis and studying for exams) I finally managed to land myself a job with Orica Mining Services. I can honestly say I didnÆt know what to expect when I first joined Orica. Most of my friends ended up working for big mining companies, while I was offered a position with one of the biggest suppliers to these mining companies. However, I had a feeling when I was discussing the role with my future supervisor during the interview process that the job was going to be awesome. I have now spent a year working for Orica and I absolutely love it! While I feel that my job is worthy of being in that FHM article, unfortunately, I donÆt think I am going to get my opportunity to be in the magazine. Apparently I donÆt look too good in a bikini! However, I would love to have the opportunity to discuss the journey that I have taken so far û from my time as an environmental science graduate, then moving on to mining engineering, to now, being part of the Orica Mining Services Graduate Program. My suggestion is to use this paper as a resource. I have learnt during my time at university, as well as my time in the workforce, that the best people you can learn from are your peers. Take what you feel is relevant from the paper; hopefully it will help guide you in shaping your own career.

Jan 1, 2005

By Samuel A. Reipas

Introduction The ore mining industry has been successful because of technological progress and huge sums of capital investment. But new technology and plants have not come cheap. The problem now is companies will run out of money before they run out of ideas. Survival Strategies Industry survival strategies demand restructuring and new plans. Inland's prescription for the future includes: • Continued emphasis on technological improvements to upgrade pellet quality and lower costs; • Effective use of human resources resulting in employee satisfaction and improved planning and productivity; • Deliberate, well planned, and documented cost-control programs for the short- and long-term; and • Capital investments to support the first three initiatives. Technology Technological changes are not only required by the need for operational improvements, but by product quality improvement dictated by the user - usually the blast furnace operator. Established ambient measurements of pellet quality, such as tumble index, compression strength, porosity, size distribution, and chemical composition, are no longer considered meaningful in predicting pellet performance in a blast furnace. New specifications, called low temperature and intermediate temperature properties, have been recently introduced. Low temperature specifications are characterized by disintegration of pellets in the 500°C (930°F) range in the upper portion of the granular zone during the hematite-to-magnetite transformation in blast furnace stack. Intermediate temperature properties (measured by 1000°C or 1800°F) are characterized by swelling, reducibility, and compression strength after reduction, reflecting conditions in the lower portion of the granular zone of the furnace. These new parameters are being used for pellet quality evaluation at Inland, and will be introduced at its Minorca mine for more routine analysis and correlation with the pellet furnace operation. With increased emphasis on quality, effective communication between the blast furnace operator, research, and the pellet plant operator is critical. At Inland, this is accomplished through technical meetings where the opportunity is provided to solve problems, establish a common understanding on the value of quality, and develop future quality standards and programs. With the degree of sophistication in determining pellet quality as it affects blast furnace operation, the future pellet plant operator will actually be producing a custom pellet. Human Resources Technological change has been a strong point at Inland, and will continue to be. However, human resource management is equally important. Is management giving sufficient attention to employee motivation and involvement? It is a way to improve productivity, reduce costs, and enhance employee job satisfaction. The industry is beginning to understand the principles and the potential for tapping employee brainpower. The payoff can be handsome. Management has to be willing to share both information and power if participative management is to live up to its potential. It has to become more flexible and be willing to adapt to change on the human side. Management should embrace rather than fear employee involvement. Given time, joint problem solving will replace adversarial attitudes and pay dividends for both sides. Productivity and product quality will improve and new dimensions of employee job satisfaction will be achieved. But, it will not happen overnight. Attitudinal change must permeate the organization from top to bottom. This change is needed to support the working relationships and give everyone a sense of direct and meaningful involvement.

Jan 11, 1983

By L. J. Barnes, R. O. Koch, J. H. Versteegh, C. J. N. Buisman, P. J. H. Scheeren

Several water treatment options have been studied and piloted. A process based on activity of sulphate reducing bacteria combines sulphate removal and heavy metal removal in one process step. The anaerobic bacteria reduce the sulphate to sulphide and consequently metal sulphides will precipitate. The final design for the commercial scale plant is described.

Jan 12, 1992

By H. Merton Ruth

THE northern anthracite fields, although facing the same economic problems as the southern fields, are confronted with the additional problem of fast dwindling reserves of anthracite which can be conventionally and economically won. The mining of coal which remains in thin beds and the recovery of pillars from areas heretofore considered unrecoverable, either by reason of cost or surface restriction, pose problems of in- creasing importance to the economic life of the northern field operations. Successful approaches have Been made to this problem and other work is being performed that holds promise. There exists in the northern anthracite field millions of tons of solid coal, the recovery of which has not been too successful due to the following inherent operating faults: inability to concentrate producing areas; the great quantities of rock to be cut and handled, lack of consideration of proper sequence and speed of second mining, and the continued use of the mine car as the basis of payment. A mining system that has successfully solved these major problems has been in operation in the Scranton area since 1944. Over 1% million tons have been produced from veins varying from 3 to 4% ft thick by this method, which is known as the multiple panel-triangular system-conveyor mining.

Jan 1, 1950

By J P. Sykes, T C. McCuaig, M Jessell, A Trench

The election of Donald Trump and the Brexit referendum herald a shift towards a tighter definition of economic value, at the expense of the broader value concept of sustainable development; as well as a rise of protectionism, reversing a long-term trend of globalisation. However, the situation is complex, especially over the longer term in which mine project development and exploration operates. The minerals sector should proceed with caution. A greater focus on the local impacts of mining may be strategically beneficial, not only to mitigate against a potential protectionist future, but also because sustainable development has become more ‘localist’ via the concept of ‘social licence to operate’, whilst globalisation also seems to provoke increased ‘localist’ sentiments (known as ‘glocalism’). Localist strategies, therefore, seem a good hedge against multiple political futures. By contrast, moving away from sustainable development appears strategically riskier. Not only are ‘unsustainable’ activities, such as pollution and civil rights infringements harder to reverse, but a movement towards a more sustainable global economy may already be predetermined, even if the journey there may seem oblique. It appears that the increased economic development that is coveted globally is intrinsically linked to a rise in environmental and social consciousness.CITATION:Sykes, J P, Trench, A, McCuaig, T C and Jessell, M, 2017. Charles Dickens on the (potentially) changing role of globalisation and sustainability in the long-term future of mining and exploration, in Proceedings Tenth International Mining Geology Conference 2017, pp 239–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By G. L. Oldright

As sponge iron is much like porous, coarse sand, it is a tempting material to use in place of coarse scrap iron as a precipitant of metals, for scrap iron is relatively awkward to handle and exposes only a small amount of surface to pregnant solutions. The results of the experiments described in this bulletin are largely a record of the behavior of sponge iron as a precipitant of lead and copper under laboratory conditions comparable to those that would obtain in a commercial plant were it attempted to secure the maximum contact of surface between solution and precipitant. Physically, the study is largely one of the rates of diffusion of the metal ions in the solutions and through the metallic coatings surrounding the sponge iron particles. The practical objectives are to remove completely the valuable metals from solution and at the same time to obtain a precipitate of good grade. In order to fulfill this latter requirement, the precipitant should be almost completely consumed. These practical ends are usually secured by having the two substances involved pass each other counter-currently-that is, in such a manner as to have the strongest precipitant in contact with the most impoverished solution, and vice versa. EXPERIMENTS WITH LEAD SOLUTIONS In nearly all of the schemes involving the leaching of lead from its ores the metal has been put into solution as the chloride, and fairly concentrated liquors have been employed. The solubility of lead under such conditions is comparatively small at best; the hot pregnant liquors from which the metal is to be precipitated are then made nearly saturated with respect to lead, and only a very small amount of acid is used. Therefore it was not as necessary to learn the behavior of the sponge iron in precipitating lead from solutions of widely differing composition as to learn under what conditions, and with what mechanisms, this precipitation might be carried out most readily.

Jan 1, 1928