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The mining industry was one of the first to be directly regulated by legislation in the 19th century when British public opinion was mobilised by reformers seeking social change. In the next wave of mining safety legislation, account was taken of technological advances in the industry, but again, the amendments were in large measure driven by public expectations following a series of disastrous mining accidents with great loss of life. The result was the prescriptive and detailed type of regulation that has, to a great extent, remained with and become a way of life in the mining industry of today. In 1970, the then British Government appointed Lord Robens, a former Chairman of the National Coal Board, to head a Committee of Inquiry to consider the arrangements then in place for preserving the safety and health of people at work and to consider and make recommendations on the need for change in the legislation governing such matters. The result was the 1972 report Safety and Health at Work which, in turn, resulted in the Health and Safety at Work etc Act 1974 (UK). This Act, which embodied the now familiar concepts of consultation with the workforce on matters relating to health and safety and the statutory application of the previously existing Common Law concept of the duty of care, became the model for much occupational health and safety legislation in many places around the world, including the various States of Australia. As a result of the `Robens style' of legislation, the regulators of the mining industry have had the opportunity to become less prescriptive and to introduce an `enabling' style in their statutes. This has not always been welcomed by the industry which has, to some extent, missed the comfort of knowing exactly what is required of it in order to ensure compliance with the legislation while appreciating the `self-regulatory' opportunities that the new style of regulation offered.

Jan 1, 1995

TO THE BOARD OF DIRECTORS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS Gentlemen: - I herewith present a report of some. of the more important activities of the Institute for the year of 1922. The outstanding feature of the year is the optimism felt by our members despite the continued depression in the mining industry. January 1, 1921, found many of our members out of employment or drifting into other industries to tide them over the depression, but almost universally the feeling has been that this was but a temporary condition and that sooner or later the necessary production of raw materials would enable these members to return to their former activities and renew their participation in Institute affairs. As the year passed conditions improved and, before it ended, many had found employment in their previous occupations. Bearing in mind that this depression has been very real, we have reason to be well satisfied with the work that the Institute has been able to do. The loss of members through inability to pay, dues has been large, and income has been correspondingly reduced, but it proved to be materially in excess of that anticipated early in the year, so that a substantial and unanticipated balance was carried forward toward the activities of 1923. PUBLICATIONS Following the example of other technical societies, and to conserve our resources, no Year Book was published in 1922. The lack of an up-to-date membership list for the use of our members was regrettable, but the saving of $5000 proved to be worth while. During the year, Volumes LXV, LXVI, and LXVII were printed and sent to members. These volumes were composed largely of the papers of 1920 and 1921, publication of which had been delayed partly through lack of funds and partly for the purpose of segregating into volumes those papers dealing with the same general subject. The segregation of papers had been suggested by a number of members who had advised that they were not primarily interested in all subjects

Jan 1, 1925

By K. K. Cheng, Z. M. Chen, A. L. Mular

INTRODUCTION Since the nineteen fifties, process engineers have been seriously concerned with process models for various purposes (1,2,3). Models serve as subroutines to mathematical flowsheets which simulate circuits of interest. Simulators can serve to increase process know- ledge, assess circuit performance, investigate flowsheet modifications, evaluate new flowsheets, perform off-line optimization, and compare alternative control strategies. This chapter describes a methodology to develop a simulator of a bulk Cu-Mo circuit comprised of roughers, scavengers and 3 stages of cleaning. The simulator was employed to evaluate the influence of water addition at circuit points and to estimate the optimal number of cells for each stage in the circuit. DESCRIPTION OF CIRCUIT Figure 1 is a flowsheet of the Brenda Mines Ltd. (located near Peachland, B. C.) bulk Cu-Mo flotation circuit as simulated prior to an expansion/renovation which involved the installation of large, new flotation cells. Referring to the flowsheet, feed to rougher cells includes fresh feed, scavenger concentrate and 1st cleaner tailing. Rougher con, 1st cleaner (sect ion 2) con and 2nd cleaner tailing are fed to 1st cleaners (section 1). 1st cleaner (section 1) concentrate and 3rd cleaner tailing serve as 2nd cleaner feed, while 2nd cleaner concentrate is fed to the 3rd cleaners which produce a final bulk concentrate. Table 1 lists cell types and specifications important to the circuit. DEVELOPMENT OF MODELS To develop flotation cell models a systematic procedure was employed (4). This involves the selection of responses and factors, proposing models to be fitted, the acquisition of raw data, the statistical adjustment of raw data, fitting models to adjusted data and testing the adequacy of fitted functions. Responses and Factors Responses of interest included recoveries, concentrate grades and concentrate solids/water flow rates for each stage. Factors that influence these responses, such as reagent addition rates, air flow rates to cells, solids and water flow rates to stages and feed grades were not manipulated during the sampling period. Thus, the investigation was limited,

Jan 1, 1986

By Robin Perry, Claude Bazin

"Discrete transfer functions which use the grinding circuit feed tonnage to predict mass flowrates at reagent addition points in a flotation circuit were calibrated using a dynamic grinding/flotation circuit simulator. Predicted mass flow values are multiplied by reagent addition ratios to obtain actual reagent flow. The transfer functions are currently integrated into the distributed control system of Les Mines Selbaie.IntroductionThe development of adequate tools for the control of flotation processes is a continuous challenge. Since the early 1970s there have been numerous publications dealing with practical aspect of control of flotation processes. Most plants use a combination of feedback and feedforward controls to reduce the effect of the following flotation process disturbances (McKee, 1991):• changes in throughput;• changes in feed grade;• changes in particle floatability (size, liberation, surface oxidation ... ); and • deliberate changes of setpoint;Feedforward control manipulates variables such as reagent and/or air flow rate to attenuate the effect of disturbances such as changes of feed rate and mineral content. The feed forward strategy is driven by measurements of these disturbances. Feedback control is used to maintain process variables to targeted set-points of concentrate or tails grades. The feedback control action is driven by deviation from the set-point, caused by a deliberate change of set-point or disturbances.This paper proposes a method to improve feed forward control schemes by the addition of a simple model for solids transportation. The feedforward strategy considered in this paper is the ratio type, in which the manipulated variable is changed according to a predefmed ratio between this variable and the measured disturbance. A typical example is the ratio of the reagent addition to mass flow of ore.The paper reviews the state of the art in feed forward control strategy applied to flotation processes and describes the method used for predicting mass flow rates. The last section shows an application of the method in the Les Mines Selbaie flotation circuit."

Jan 1, 1994

By Hongzhen Yu, Xiaoping Ma, Jiansheng Qian

The paper introduces the design of an Intelligent Managerial Attendance Machine (IMAM) for coal mines. In the system, data communication is carried by Optical fiber communication, including industrial control computer on the ground and the car

Jan 1, 1998

By J Youngson

Gold placers can be difficult to locate in areas where tectonic activity and paleogeography have changed significantly since placer formation. Existing placer exploration models are useful in areas that have a relatively simple geological history, identifiable relationships with parent sources, or a history of placer mining. However, exploration becomes increasingly difficult in areas where tectonic activity and sedimentary recycling repeatedly redistribute the gold. Gold placers in the Waitaki River catchment, North Otago, New Zealand have no primary source within the catchment. During the Eocene placer gold was transported by a river ('Buster River') that flowed in a northeast direction from Central Otago toward a coastline at Maerewhenua, North Otago. This river and coastal system was inundated by marine transgression during the middle Tertiary. Since the Miocene its placer deposits have been uplifted and eroded and any links with parent sources have been severed. Changes in paleogeography resulted in local reconcentration and local dilution of placer gold in different areas in the Waitaki catchment. Thin veneers of old Waitaki River gravels (Kurow Gravels), containing gold recycled from the older placers, have been deposited unconformably on strath surfaces cut into Tertiary or older rocks. These gravels along with remnant Eocene fluvial and shallow marine strata provide potential placer exploration targets. Uplift and erosion of non-auriferous rocks in the Waitaki catchment to the west and north of the study area has resulted in considerable dilution of potential placer deposits downstream, especially in areas of gravel aggradation. We present a placer exploration model that is founded on answering fundamental questions pertaining to the paleogeography and geological history of the sediments associated with the placers.

Jan 1, 1999

By Michael K. O’Leary, William D. Coplin

"Risks from political instability and government policies restricting equity ownership, local operations and transfers of payments affect the profitability of foreign mining ventures. More than seat-of-the-pants judgments and old-boy networks are required to anticipate these risks and to take actions appropriate to offsetting them. A system for making political forecasts, called the Prince System, and a series of charts relaying risk s to a production of key minerals will be presented.IntroductionFirm s with extractive operations outside their home country do not have to be told that political stability and government decisions play a big role in the success o f their operations. The takeover of copper firm s in Chile during the Allende administration in 1971 and the recent decision by Venezuela to reduce Reynolds Metals equity share in a smelting operation from 50% to 28% are two examples of hundreds of events that have determined the profitability of extractive operations over the past decade. Both risks and opportunities for international firms seeking to produce and market raw materials are heavily affected by political conditions. While news of political events travel much faster than in the past and host governments are more clever in shaping the risks as well as the opportunities, politics has always been part of the mining business.What has changed is the need to be more systematic in approaching the assessment of political conditions and how it affects business. The increasing costs of extractive operations, the need for long-range planning, the importance of financial arrangements and the world-wide scope of man y firm s' activities require that the assessment be updated continuously and be comparable across different countries and different types of investments. Political risk analysis, the assessment o f macro-political changes and specific governmental decision s on the operations of extractive industries needs to become as systematic and integrated into corporate decision -making as economic analysis has become over the past two decade s."

Jan 1, 1983

Mine production planning and scheduling as a production planning problem can be handled using Linear (Goal) Programming. This approach is particularly useful when the product quality is important. This has been shown for many mine planning cas

Jan 1, 1998

Effect of Hydrophobicity and Frother Concentration on Bubble-Particle Interactions in Turbulent Flow

Sep 13, 2010

By G. Granger, D. Malhotra

The paper briefly reviews the criteria employed in the selection of chemical reagents for testing and discusses the steps involved in laboratory and plant evaluation of these reagents. An example of successful implementation of reagent change in the plant is illustrated.

Jan 1, 1986

By L. Janku, G. Hancox, M. Villenueve, C. Massey

Wellington lies in a seismically active area 150 km from a subduction zone and in the vicinity of several active faults, which poses a risk to its infrastructure and inhabitants. One of these major faults, the Wellington Fault, runs through the centre of the city and across several lifelines, including the natural gas pipeline and the freshwater pipeline. The first settlement in the area was severely damaged in 1848, soon after its establishment, by an earthquake of approximate magnitude Mw 7.4 - 7.5 (Grapes, Little, & Downes, 1998). In 1855, another earthquake of magnitude Mw 8.2 generated by a nearby fault uplifted the eastern part of the current Wellington area and caused several landslides in the surrounding hills (Grapes & Downes, 1997). The Central Business District lies in the area of a sedimentary basin and partly on reclaimed land. Many residential areas, as well as some vital infrastructure, however, lie on or along the slopes in the surrounding hills. The bedrock in the area comprises predominantly the Torlesse greywacke of Permian – Late Triassic age. The greywacke is tilted to a steep angle, intensively faulted and fractured (Cook, 2001). Even though several studies in the past assessed the seismic risk in the area (e.g. Brabhaharan, Hancox, Perrin, & Dellow, 1994), the studies either focussed solely on the area of the sedimentary basin or based their assessment of the hilly terrain purely on slope morphology (slope angle). Previous studies have shown that slope shape and contrasting materials in the slope can amplify earthquake ground motions, such factors are typically called site effects (e.g. Geli, Bard, & Jullien, 1988). Any attempt to systematically quantify the site effects and consequent seismic response of the slopes and use it to predict the consequences of the next large-magnitude earthquake, has not yet been carried out. In this extended abstract we outline the methodology of a PhD research project, focussed on investigating the site effects on the slopes around Wellington and on creating representative numerical models of ‘characteristic’ Wellington slopes and materials. This extended abstract presents the methodology adopted for the assessment using the Te Ahumairangi Hill site as an example.

Jan 1, 2015

By S. Asano

Hydrometallurgical processes for treating copper sulfide concentrates have attracted considerable attention over thirty years and many processes have been developed. However there have been still problems in those processes because of difficulties of iron removal and high purity copper production with low operating cost. Although SX-EW is highly cost effective method, it is difficult to process the chalcopyrite. Sumitomo Metal Mining Co., Ltd. (SMM) conducted a review of hydrometallurgical copper concentrate processing and has successfully developed a novel process for the hydrometallurgical production of copper from copper concentrate. In this process, copper sulfide is leached by chlorine gas under atmospheric pressure. Most of hydro metallurgical processes can leach only some of chalcopyrite under atmospheric pressure then they need high pressure leaching facility like autoclave. In this process, copper in chalcopyrite can be leached completely by controlling oxidation reduction potential and chloride ion concentration. Cu(I) ion in leached liquor is separated from Fe(I!) ion by SX using TBP then pure copper powder is produced by electrowinning. Results in batch and continuous testworks and pilot plant tests at Niihama Research Laboratories are presented in this paper. Cu2007

Jan 1, 2007

By Paine GG

The in-situ retorting of shallow oil shale deposits is an attractive alternative to the material handling problems of conventional open pit mining techniques, which involve removing overburden, fragmenting and transporting the shale to a fixed retort, and finally disposing of the hot spent shale.For in-situ retorting to be successful, the oil shale has to be fractured and the fragmented rock expanded into a void, to allow controlled propagation of a flame front through the in-situ retort. The principles of cratering with explosives have been used to develop a process for the in-situ fracturing of a thin oil shale deposit overlain by a formation of porous rock. The overlying porous rock formation is first compressed by explosive charges to create voids in the porous rock. The oil shale is then fragmented and pushed in to the voids with separate explosive charges. This paper discusses methods of creating voids in porous rocks with minimal surface disturbance, and then methods of obtaining the most uniform fragmentation of the shale. The whole process can be completed, in practice, in one blast. The results of an experimental blast are presented, and possible modifications are then discussed.

Jan 1, 1985

By Yanping Xiao

In submerged-arc furnace (SAF) for smelting chromite ores into ferrochrome, there exist large temperature gradients and wide distributions of mineralogy and compositions in the furnace, due to the complexity of feed structure and electrical-thermal-chemical interactions. This leads to various zones in the furnace and thus different reaction mechanisms. In the present paper, the behaviour of chromium in the submerged arc furnace is discussed in various reaction zones, including solid state chromite reduction in the packed bed zone, chromite dissolution and reactions in the smelting and coke bed zone, and recovering chromium from slag to metal. In the gas-solid reaction zone, the reaction mechanism is discussed based on the experimental observations and analysis. In the smelting zone, the behaviour of partially reduced chromite and slag formation are analyzed based on the information in literature. The slag in FeCr process contains mainly Al2O3, MgO, SiO2, CaO and CrOx, featured by chromium with both divalent and trivalent oxidation state, which plays an important role for chromium recovery into metal. The factors influencing the slag and metal interfacial reactions and the chromium recovery are addressed.

Jan 1, 2006

By F. Mauviel, J. Bernard, G. Herrouin, J. P. Lenoble, C. Charles, B. Taine

Manganese nodule projects were quite fashionable during the 1970s. At the beginning of the 1980s, low metal prices led to an almost complete reduction of such activities; however, the Law of the Sea incited the countries that signed it to build a strategy for this ocean resource. Gemonod was created in France in 1984 with a four-year mission. This paper presents the results of its program devoted to the technical and economic studies of nodule exploitation. A commercial mining system is presented. The nodules would be collected by a self-propelled miner and lifted hydraulically through a rigid pipestring. A complete optimized scenario has been built taking into account offshore mining, ore transfer at sea, transportation and processing to analyze the profitability of the project. Considering an average conservative basis for metal prices, after a deep analysis of the market, the return rate of investment of the project appears fairly interesting. These results are new and are explained in comparison with previous foreign studies. These results must not hide the innovative nature of the project nor the associated risks. This is why a mining pilot is required and has been specified by Gemonod.

Jan 1, 1991

The Pacific Rim and its environment involves a vast array of natural phenomena, and a vast array of situations which show the impact of man. Almost half the world's population of over five billion live in nations" which border the Pacific, but the concentration is focussed in the North. Great experiments are occurring in this region, the industrialization and energy development in- Japan and China, the growth of Indonesia, (now 168 million - soon 368 million; Brown and Jacobson, 1986), the enormous developments of agriculture and the metals resource base in Australia and China. At the same time, the Pacific Rim does not project images of hopelessness, the mood is upbeat. Over the past decade, incomes have increased substantially in most of the major countries of Pacific Rim (e.g. over the period 1980-86, + 58% in China, + 21% in Japan, + 34% in South Korea; Brown and Jacobson, 1986). In September, 1986, at the general assembly of the International Council of Scientific Unions (ICSU) in Bern, Switzerland, representatives of over 50 nations approved a new initiative, "The International Geosphere Biosphere Programme: A Study of Global Change". The focus of this new program is "To describe and understand the interactive physical , chemical , and biological processes that regulate the total Earth system, the unique environment that it provides for life, the changes that are occurring in this system, and the manner in which they are influenced by man. The IGBP will be a tightly-defined programme of research, directed at providing fundamental knowledge that will serve as a basis for assessing likely future changes on the Earth in the next 100 years" (ICSU, 1986). For the earth scientist, and all resource scientists, there is an emerging agenda; new priorities are appearing, new questions are being asked. The recent report of the World Resources Institute (1986) focusses on this emerging agenda. Topics which are at centre stage in this report include the following: The environment and human health Tropical deforestation The atmosphere as a shared resource and climates Soil-degradation Rural-urban migrations Food and agriculture The diversity of species-ecosystems Freshwater as a finite resource Coastal areas and resources

Jan 1, 1987

By J. B. C. Wu, B. McKee

"Mining along with subsequent processing of the minerals often presents conditions where a wear- and/or corrosion-resistant alloy is needed to minimize downtime and maximize efficiency. This paper is intended to give an overview of the alloys that are currently being used, as well as those developed in recent years that could be used in the mining industry. Emphasis will be put on the iron-, nickel-,cobalt-based alloys and composites containing a variety of carbides. The characteristics, properties, product forms, and methods of application are presented. In addition, examples of the actual use of these wear-resistant materials are illustrated.IntroductionPreventing wear and corrosion is important in any industrial operations. In the mining industry, the process equipment typically suffers many different types of material degradation. Abrasion, impact, erosion, metal-to-metal wear and corrosion are typically encountered. Each situation requires different material characteristics to retard the degradation process. Therefore, it is essential to understand the characteristics of the materials and the effects of the alloying elements.There are four common classes of metallic materials for resisting wear and corrosion; namely, iron-based alloys, nickel-based alloys, cobalt-based alloys, and carbide-containing composites. Each class of material has its own characteristics. Depending on the chemical composition, the materials within each class can be vastly different in properties. In recent years, there have been materials developed in each of the four classes using the knowledge of the metallurgical principles and the effects of the alloying elements on the material degradation process.To use a wear-resistant alloy, it is also necessary to understand the available product forms and their application methods. Weld overlaying is a traditional way of using these alloys (Wu and Redman, 1994). In recent years, thermal spray is becoming popular. For applications where over-laying and spraying are impractical, solid components can be made by a variety of casting and powder metallurgy techniques. They can also be fabricated from the wrought products.To select a proper material for an application, it is important to understand not only the characteristics of the wear-resistant materials but also the degradation process. Due to the complexity of the processing environments, past experience is also helpful in making the decision on the material selection."

Jan 1, 1997

By J. M. Ohm, C. M. Bunker

Two special tools for recovering gamma-ray probes and logging cable from drillholes have been designed by Ohm and Bunker and constructed by Ohm. Though intended specifically for U. S. Geological Survey equipment, they may be used with other equipment of the same general type. Fishing Tool for Probes: A fishing tool of the overshot type (Fig. 1) was designed to retrieve logging probes (sondes) that become disconnected from the logging cable and are trapped in the drillhole. When the tool slides over the top of the gamma-ray probe, studs on the bottom engage the shoulder near the top of the probe (Fig. 2), which is then pulled to surface. The barrel can be constructed from brass or steel tubing. Wall thickness is not a critical dimension, but the tool should be heavy enough to sink through mud or water in the drillhole. The internal length of the tool must be enough to prevent interference with the upper end of the probe head as the tool slides over it. The design of the probe head used by the USGS required a minimum free space of 2 1/2 in. inside the fishing tool, which was made 7 1/2 in. long to increase the weight. The lower end, which engages the shoulder of the upper end of the probe, contains three studs placed at 120" around the circumference of the tool and held in the engaging position by the tension of a spring wire. The studs can be made of any metal, such as steel, having high tensile strength. As the tool slides over the probe the studs are pushed outward from the center against the spring tension, allowing the tool to slide into position below the shoulder of the probe head. The spring tension forces the studs inward into the engaged position after they pass the shoulder. When the tool is raised the studs stop against the shoulder, preventing the tool from sliding up over the top of the probe. Once it engages the shoulder of the probe it cannot be freed until both probe and fishing equipment are recovered from the drillhole.

Jan 1, 1960

By J. E. Schaefer

A summary of oil and gas development in Ohio for 1936 is necessarily brief and, in some details incomplete, owing to the lack of a central state agency for the collection of data and statistics on well drilling and production. The information used in this report was compiled from the records of the several companies operating in the state. Drilling activity in Ohio increased during 1936 as compared to the two preceding years. During the year 1157 wells were completed, as compared to 1022 wells in 1935 and 1055 wells in 1934. However, in spite of this increase in drilling activity, both oil and gas production declined for the year. Activity by Fields Trenton Sand Field.—The Trenton sand field is located in 15 counties of northwestern Ohio, trending from Toledo on the north, south and west through Findlay into Indiana. About 40 years ago the Trenton field was one of the most important oil-producing fields in the United States, but it has declined to a position of minor importance. During the year 1936 there were 52 completions in this field—29 gas wells, 19 oil wells and 4 dry holes. Clinton Sand Field.—The Clinton sand is by far the most important gas-producing field in the state. Production is located in small pools separated by nonproducing areas, on a band of varying width reaching from Cleveland on the north to Lawrence County on the Ohio River on the south. During 1936 a small pool of patchy character was developed in Butler township, Knox County. Seventeen wells were completed in the Clinton sand, of which 13 were gas wells and 4 were dry holes. The average initial production secured per well drilled, including dry holes, was 1,288,000 cu. ft. The average depth of the Clinton sand was 3000 feet. A gas well was completed in lot 9 of Franklin township, Tuscarawas County. Production was found in the first Clinton sand at a depth of 4354 ft. The initial open flow after shot was 828,000 cu. ft. and the rock

Jan 1, 1937

By C. D. Anderson

"IntroductionTungsten carbide is a valuable material used in a variety of different applications, including the manufacturing of cutting tools, bearings and as a cost-efficient alternative to industrial diamonds. Both the high hardness value (Mohs 9) and scratch resistance of this material make it a valuable commodity for use in the mining industry.Usually, the production of tungsten carbide is a multistep process involving one or more of the following unit operations: hydrometallurgical digestion, solution purification, crystallization (as ammonium paratungstate), calcination, hydrogen reduction and carbon synthesis. The proposed three-step process eliminates three of these steps (crystallization, calcination and hydrogen reduction) by implementing a combination of hydro/pyrometallurgical techniques. These include alkaline pressure leaching, carbon adsorption and carburization roasting. By eliminating some of the intermediate processing steps, there is potential to reduce energy consumption and decrease overall operating costs.Methods and resultsInitially, alkaline pressure leaching with sodium carbonate (Na2CO3) was employed to selectively leach tungsten, as tungstate (WO4 2-), from an industrial Scheelite (CaWO4) flotation concentrate. Experimental variables included lixiviant (Na2CO3) concentration, temperature and residence time. Experimental constants, based on previous work, were percent solids at 13 wt% and agitation at 400 rpm (Queneau and Strathmore, 1969). Leaching results showed it was possible to extract 97% of the tungsten present. The most favorable conditions for leaching were determined: 2M Na2CO3, temperature of 180° C and a residence time of 30 minutes."

Jan 1, 2015