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By J. Herhold, S. Plaum

"Current and future operational processes in the mining and underground construction sector are under the influence of the prevalent competition and the acute necessity of optimization approaches concerning corporate and project processes. Besides general construction procedures, especially underground construction procedures and procedures in the field of deep shaft construction are high-profile. Those processes describe high technical challenges as well as increased requirements to occupational safety and health. Therefor an occupational safety management, which should be adjustable to the company itself and adaptable to all kinds of projects, shall be created. The creation of such an occupational safety management would lead to an economically optimized and safe (within the scope of OSH law) implementation of internal activities for the performance of construction services underground and in the field of deep shaft construction. With this approach the satisfaction of the high safety request as well as the demand for process optimization, as part of keeping the own competitiveness, will be satisfied successfully at once. PROJECT BACKGROUND Introduction The health and safety protection as well as occupational safety look back on a long historical development, which had brought more important sectors and developments during the last years, not only in Germany but also on the European and international level. The accident insurance protected by law has already been reported in 1884, which is astonishing early. The launch time point is strongly connected with the on-going economic development in the end of the 18th century, but above all this increased in the 19th century. The progress of occupational safety and especially the interest in the integration and the concentrated consideration of occupational safety and the health and safety protection in the company process is strongly visible during the 19th century and directly connected to the industrial revolution. [9] The industrial revolution and with that the development of work places lead to changing demands in the field occupational safety and health and safety protection. Insufficient security precautions caused problems in the industrial revolution, such as personnel and material losses as well as serious injuries and their consequences. These and the fundamental economic endeavours of the entrepreneurs lead therefore to the important step to develop an occupational safety system. [9] The prevailing basic ideas seize the insufficient security precaution of work places as well as the economical and profitable ideas of the entrepreneurs and bring them together. From this the necessary entrepreneur’s task comes into being and that is bringing the work conditions to the way that life and health of employees are not in danger. [9]"

Jan 1, 2017

By CHENGLONG XU, HAORAN LI, YALI FENG, JINRONG JU, Shunliang Liu

With the depletion of mineral resources and the growing demand for metal resources from industrial development, the recovery of metal resources from secondary resources has attracted increased attention. Among all secondary resources, spent catalyst is one of the most important as it contains valuable metals such as vanadium, nickel, molybdenum, cobalt, and aluminum. Compared with the extraction of metals from minerals, the recovery of valuable metals from spent catalysts has the advantages of a simple process, a short production cycle, lower investment cost, and less environmental impact.

Apr 1, 2023

By F. Dehghani, M. Kebe, H. Askari-Sabzkoohi, T. Ghosh

The depletion of bauxite reserves around the world has necessitated the search for viable alternative sources of aluminum. The major non-bauxite source of aluminum is alunite [KAl3 (SO4)2(OH)6]. Lixiviation is the common industrial process to recover aluminum from alunite. Due to the presence of quartz (40%) as the main gangue mineral, this process causes the formation of Sodium aluminosilicate and Potassium aluminosilicate complexes that leads to loss of alunite, and chemical reagents. Thus, pre-concentration of alunite is required to remove the gangue minerals. Because of the low degrees of freedom (DOF) of alunite, froth flotation, as a preconcentration method, is a viable alternative to increase selectivity in downstream processes. In this work, the possibility of Alunite preconcentration with micro flotation and mechanical flotation cells was studied. The influence of type and dosage of collector, pH, solid percent, particles sizes were considered on the flotation. Flotation tests were designed based on Taguchi method, followed by performing based on surface charge differential between alunite and quartz on direct and revers flotation. In the reverse flotation, Ca+ 2 and Ba+ 2 were used to activate the quartz surface. Under optimum conditions of reverse flotation, alunite grade and recovery were 40% and 62.1% respectively. In the direct flotation, the surface of alunite was activated by F- . The grade and recovery were 50 and 89%, respectively.

Mar 2, 2022

By A. L. Mular

Se revisan brevemente varios procedimientos para el cálculo de coste de capital; no obstante, se discute en preferencia el método del factor estimado. Se proporciona una tabla de costes frente a los datos de parámetros de equipo, de donde los costes pueden ser adaptados a partir de los valores actuales de los índices de costes M&S para minería y molienda. Las ecuaciones de costes son utiles para preparar los programas de computador que realizan cálculos de coste de capital. Se ilustra la utilización del metodo del factor estimado.

Jan 1, 1982

Automated drilling in surface mines is here, it?s successful, and it?s already at work in mines around the globe. Coal, copper, iron and gold mines in large mining countries such as Canada, Australia, South Africa, the United States and Chile are meeting mining objectives previously ruled out as unattainable. Pit Viper automation enables operators to accomplish more objectives safely. Operator assist functions like AutoLevel, AutoDrill, Auto Rod Changer and multi-rig teleremote control are a few of the features mines are using to gain consistent, sustainable productivity.

By George E. Aiken

Agglomeration developments in the iron ore industry of North America are closely related to shifting patterns in commercially acceptable ore grades and even the definition of iron ores. These relationships have occurred mainly during the last 20 years. Many of these changes are an outgrowth of events which involved the history of the Mesabi Range. Although magnetic taconites had been discovered in the Lake Superior area about 1870, they remained unvrorked in part for lack of concentration methods and a generally unfavorable economic climate. Some 20 years later the rich Mesabi hematites were found beginning the era of direct shipping ores which continued through World War II. These Lake Superior iron ores included reserves of an estimated three billion tons. Following World War II, decreasing ore grades and rising costs began to force the closing of many underground iron mines. The early 50's saw the beginning of the decline in direct shipping ores and a spurt in produc- tion of natural iron concentrates. However, the market for unprocessed concentrates began to decline in the early 60's as agglomerated products and foreign ore s began to dominate the U. S. market.

Jan 1, 1973

By J. S. Ross

The significance and role of industrial minerals in Canada differ from those in the United States, The smaller Canadian industry has recently become well diversified and self-sufficient in most commodities, However, it depends on exports, principally to the United States, for much of its market, Imports are small, but imports of several basic products manufactured from industrial minerals are large. This nation is a leading world producer of asbestos, gypsum, sulphur, nepheline syenite, titania slag, potash and barite. It has reserves in asbestos for at least 30 years enough potash to supply the current world's needs for 2,000 years and sulphur reserves for 40 years of current world demand, One of the ilmenite deposits contains enough titania to supply the current world demand for at least, 25 years.

Jan 1, 1964

By K. Fair

Using an agitated column 203 mm (8") diameter by 1829 mm (72") tall with independent agitation units for the gas dispersion zone and the collection zones, respectively, permitted the independent evaluation of the attachment and the detachment mechanisms for the chalcopyrite/ silica system. Three particle size fractions were used in this study, i.e. coarse (+75 µ m), intermediate (-75 µ m + 10 µ m) and fines (-10 µ m). The optimum selection of the two agitation zones for the three particle size fractions were determined as a function of grade, recovery, residence time and air superficial gas velocity.

Jan 1, 1990

By E. A. Sigworth

Our interest in metallurgical applications for activated carbon was thoroughly aroused when laboratory studies indicated that each dollars worth of carbon could retain as much as four dollars worth of tin. Since then other data was developed suggesting many Potential uses in the metallurgical field it is hoped that, the information presented in this paper may encourage studies by knowledgeable individuals in metallurgical operations. Activated Carbon accomplishes its results by adsorption which involves selective removal of materials from solution by holding the compounds on the carbon surface at the active areas. An example of adsorption is the dyeing of cloth where the dye is selectively held on the cloth surface and the concentration in the dye solution is thereby reduced. Many theories exist on, adsorption, but the predominant factors involved in metallic ion adsorption probably are that adsorption is indirectly proportional to solubility and is benefited by high concentrations acting to squeeze out molecules in smaller amounts.

Jan 1, 1962

By Zhongran Dai, Nan Hu, Jianhong Ma, Hui Zhang, Zhihua Zhong, Han Zhou, Feng Li, Yonggen Qiu, Yang Ding, Yingchun Yang, Dexin Ding

In the traditional chlorination roasting-water leaching-solvent extraction process for the extraction of rubidium-bearing ore, Rb leaching from the ore and calcium removing from the leachate are conducted separately, and this results in the complicated process and high energy consumption. In order to integrate the Rb leaching and calcium removing processes, Rb-bearing polymetallic ore was firstly treated by chlorination roasting, it was then leached in a micro-reactor with raffinate, and the calcium ions in the leachate were removed in the reactor as carbonate precipitates by passing CO2 at certain pressure into the reactor. The effects of raffinate alkalinity, CO2 pressure, and CO2 reaction time on Rb leaching rate and calcium removing rate were investigated. The experimental results show that when Rb-bearing polymetallic ore was leached for 90 min by stirring with raffinate with 1.125-mol/L alkalinity, and the pulp was made to react with CO2 at 0.8 MPa for 15 min, the Rb leaching rate and calcium removing rate amounted to 92% and 98.2%, respectively. This integrated process including Rb leaching from Rb-bearing polymetallic ore and calcium removing from leachate could simplify the process for the extraction of Rb-bearing ore and increase its economic benefits.

Sep 27, 2023

By Ernest N. Wolff

You here are all familar with the myriad of new laws, some enacted and some pending, that affect the mining industry. These laws, for example those dealing with suspended matter, affect us in Alaska as they do you. Likewise, our friends in government, the Geological Survey and the Bureau of Mines, provide us with the same fine services that they do elsewhere. I am not going to speak today about these, but concentrate on one act of Washington, D.C. the impact of which is felt, for now at least, principally in Alaska. A little more than a year ago, I spoke in Spokane on the subject, "Governmental Challenge to Mineral Development in Alaska." I outlined some of the policies of Government which were operating to change the rules under which the industry operates and to alter the relation- ship between government, industry, and the individual. At that time the Native Claims Settlement Act had not been passed, but was on the verge of being so. In reading over what I said in Spokane, I note that I touched on many points where Government was actually challenging mineral development in Alaska. With the passage of the Alaska Native Claims Settlement Act, many of these actions were given a cloak of legality, and machinery was set up to concentrate the drive to tie up the public domain, machinery which will allow govern- mental control and interference with the actions of individuals on something like 90% of Alaska's land surface. This remarkable law is going to affect each and every one of you. Now, a year after its passage, we are only just beginning to see its lesson for the future. It was created by a coalition of powerful groups, who got other groups to support them by promising to deliver something they had no intention of delivering. Alaskan issues are again being used to get various groups not to oppose legislation which will severely harm them. It will help to understand the nature of this new drive if we understand the Native Claims Act and how it came into being.

Jan 1, 1973

By N. J. Themelis, W. H. Dresher

Research is probably the least understood and the most underrated or overrated, depending on the circumstances, function of the corporate enterprise. Some companies become engaged in research because they consider it to be vital to their very existence, others in order to develop new business, and some with no clearer objective than to keep up with the competition. Whole new industries have resulted from research activities, such as the Xerox copier, the transistor, the computer, and have affected considerably our way of life. Companies have prospered or perished by pursuing the successes or failures of their research organizations. However. despite the tremendous effect that research has had on our modern civilization and the billions which are spent on it annually, we have not as yet been able to develop many hard and fast rules as to how to conduct it effectively and to a successful end.1 This section discusses the role of research in the United States and in the mineral industry and describes a few of the criteria and guidelines which have been developed to assist in increasing the probability for success in industrial research. Broadly speaking, the purpose of industrial research is to make a significant contribution to the long-term viability and the profitability of the sponsoring company. The sum total of technological developments has been a principal factor in establishing the United States as a world leader and the controlling element in the nation's balance of trade with foreign powers. The international aspect of most mineral commodities is a significant factor in the business decision-making of most domestic mining companies and should be an important factor in the operation of research and development (R & D) programs in these companies. The National Science Board has reported that in recent yean other nations have been gaining on the United States over practically the entire range of science. 2,3 On the positive side, the NSB reported a strong position for the US in the results derived from its investment in R & D. If the United States is to maintain a favorable trade balance, it must create new know-how through technological innovation in order to create new industrial products, processes, and services for which there is a global demand. As expressed by Chauncey Starr, president of the Electric Power Research Institute, "Unlike resources found in nature, technology is a man-made resource whose abundance can be continuously increased, and whose importance in determining the world's future is also increasing."' In recent years, the greatly in- creased pressures for environmental quality and energy conservation have enhanced further the role of technical innovation in insuring the future survival of the domestic industry. Technology is the challenge of American industry, and it is a challenge which the mineral industry must also accept, for processed minerals are the very raw materials and energy on which all of industry is based, it is technology which makes a mineral deposit into an ore reserve. The Natural of Industrial R D Research is usually thought of as being either basic or applied. Basic or fundamental research is the quest for knowledge and need not have any practical objective. Applied research is the search for a solution to a particular problem and therefore has a specific objective beyond the acquisition of new knowledge. Development is the next stage to the applied research experimentation and it generally consists of larger-scale tests to establish the technical and economic feasibility of the new process or product and to provide design information for its industrial implementation. The terms research and development are usually interconnected for the good reason that in many cases it is difficult to define where one ends and the other begins. For instance, in many cases, thermodynamic, kinetic, corrosion, and other research studies, which are needed to provide design data for an industrial plant, may prod in parallel with the pilot plant activities preparatory for this plant in order to conserve time. Often the final stages of a development project may involve the trial production of a new product for markeing tests or the trial operation of a new process on a "semi-industrial" scale pilot plant. Such operations may be termed "demonstrations"; hence, more

Jan 1, 1985

By H. E. Rojas

The primary objective of most comminution operations is liberation; however, mill performance is generally quantified in terms of particle size. Only recently has the use of image analysis equipment made it possible to quantify mill performance on the basis of liberation. In this investigation, a series of tests were carried out to study the effect of mill operating parameters on the liberation of sphalerite from a sphalerite/dolomite ore. The parameters studied included mill rotational speed, mill loading and ball size. The results of this work appear to indicate that sphalerite liberation is improved under conditions that promote impact breakage, while dolomite breakage is enhanced under attrition conditions.

Jan 1, 1990

By Daniel Maine

Swelling clay soils have been problematic to many types of infrastructure in the United States. However, their impact on underground construction is often misunderstood. The use of swell pressures in design of initial tunnel and shaft support lacks proper guidance and is often mis-interpreted. This paper provides insight and guidance on how to implement a geotechnical investigation program to determine if swelling soil exists at a site and how it impacts the design of temporary support systems for underground projects. An example is provided for how swell pressures were incorporated into the design of an initial support system for a rib and lagging tunnel system and problems that occurred.

Jun 23, 2024

By Fan Yang, Zhiping Wen, Tiancheng Nie, Jinhe Pan, Ruibo Jia, Changchun Zhou

Rare earth elements have important strategic significance and economic value, and the rare earth elements in coal resources have considerable development potential. This study took coal refuse in the Jungar area of Inner Mongolia, China, as the research object, and investigated the occurrence modes of rare earth elements. A special sequential chemical extraction experiment was designed, and the results showed that the rare earth elements in coal refuse mainly occur in silicate and aluminosilicate form, accounting for approximately 65% of the total rare earth elements. According to the results of SEM-EDS, micro morphology of the sample belonged to the lamellar structure of clay minerals, and Al, Si, Fe, S, Y, and La were all present in the sample. Through SPSS software analysis, rare earth elements have an obvious linear positive correlation with Al, Si, and Fe elements, and a negative correlation with S elements. The rare-earth element occurrence mode in coal refuse can provide a definite theoretical basis for the later extraction and enrichment work.

Feb 18, 2022

By Cristian Saavedra, Patricio Zarate

Flotation collectors play a crucial role in mineral flotation by selectively adhering to mineral surfaces and aiding in their separation from gangue material. They are heteropolar molecules, as defined by Sutherland and Wark (1955), featuring non-polar hydrocarbon chains and polar groups interacting with mineral surfaces to induce hydrophobicity selectively. The importance of collectors in mineral processing, as underscored by Lotter and Bradshaw (2010), lies in their ability to enhance recovery rates and improve selectivity, thereby optimizing the extraction of valuable minerals from complex ores. Collectors are classified based on their mechanism of action, as proposed by Laskowski (2010). This classification categorizes collectors into three groups: water-soluble compounds, water-insoluble “oily” collectors, and water-insoluble amphipathic compounds forming molecular films at the water/gas interface. This complements the chemical structure-based classification by Sutherland and Wark (1955) and Suoninen and Laajalehto (1993), offering a comprehensive understanding of collector diversity in flotation systems. Collector selection is an iterative process crucial for optimizing mineral processing efficiency, as emphasized by Lotter and Bradshaw (2010). Understanding the significance of collector mixing or synergy outcomes is paramount for enhancing mineral flotation efficiency and sustainability. Taguta, O’Connor, and McFadzean (2018) demonstrate that mixed collector systems enhance interaction enthalpies and microflotation recoveries, indicating improved performance. McFadzean, Castelyn, and O’Connor (2012), along with Critchley and Riaz (1991), delve into investigating synergistic interactions between collectors, offering insights for strategic selection. Observations from the study of collector synergy, as noted by Wakamatsu et al. (1980), reveal nuanced relationships surpassing individual collector behaviors. The methodology outlined in this paper provides valuable guidance for classifying and selecting collectors based on specific application needs, while also suggesting the potential for synergistically improving recovery across fine, intermediate, and coarse particles.

Feb 1, 2025

By Ali Ekrem Aritan

Exposure to hand-arm vibration (HAV) among the labor force in the mining industry can result in permanent vibration diseases such as behavioral disorders, visual impairment, osteoporosis, pain (mostly in the hands, wrists, and shoulders), circulatory system disorders, and malnutrition. In this study, the vibration exposure of excavator operators working regularly in 25 different natural stone quarries was measured. In addition, the relationship between vibration exposure and rock properties was investigated. Gloved and ungloved vibration measurements were performed and revealed that antivibration gloves reduce excavator operators’ vibration exposure by 7.10–25.95%. Samples from each quarry were characterized with rock mechanics tests. The correlations between the hand-arm vibration measurements and the natural stone physical–mechanical properties (uniaxial compressive strength, Shore hardness, Knoop hardness, apparent density and total porosity) were determined to be over 70%. One finding of the study was that the health risk in excavators cannot be reduced sufficiently by the sole use of antivibration gloves. Furthermore, the excavation of any rock with a Knoop hardness above 121 is associated with an 81% risk of HAV. To increase awareness of the danger of vibration exposure for natural stone miners, training programs should be provided, and technical and operational changes should be implemented.

By Sean Dessureault

The mining industry has used fleet management systems (FMSs) for decades. These systems were developed long ago in large truck-and-shovel mines, where hardware sales were the core business driver for vendors. These traditional models can be overhauled in the era of the Internet of Things (IoT), Big Data, gamification and low-cost tablet technology. Relatively low-cost tablets are ubiquitous in modern life, and they are packed with communication radios and sensors like Global Positioning System (GPS) and inertial measurement units used widely for games, fitness measures and navigation. These powerful computer devices provide the same, if not more, sensing capability than traditional fleet management hardware, all at a fraction of the cost and without complicated cables or challenging supply lines. 

By Georgene Renner, Chee Theng, William Gleason

"More than 6,300 people attended SME’s 2016 Annual Conference & Expo in Phoenix, AZ and many of them made the trip to the conference to take part in the excellent technical sessions that are presented on a yearly basis by the Society.Holding true to form, this year’s conference was full of options. In fact, this year there were 121 technical sessions and 751 presentations to chose from. The following is a sample of some of the technical sessions as seen through the eyes of the editors of Mining Engineering and SME technical papers.SME Sections Sharing Success: Changing thePublic Perception of MiningThis session was a workshop on how several local sections were effective in getting the message out to their communities and schools about the value of the extractive minerals industry. Several sections shared their outreach successes, including the Mining in Society merit badge activities by the Minnesota Section by Julie Lucas and SME’s participation in the World Scout Jamboree in Japan by Frank McAllister.Dan Alexander highlighted activities by the Pittsburgh Section, such as preparing minerals kits and pamphlets for elementary school classes and regional science fairs. The West Virginia University Student Chapter used the kits as handouts at their local gem and mineral show. School speakers in full mining gear were especially interesting to the young children.Other speakers were Michael Linn, Paradise Valley Unified School District — Business and School Partnerships; and Greg Kruse, Central Wyoming Section of SME — What makes a successful section?Engineering Competency ModelAmerican Association of Engineering Societies and the U.S. Department of Labor, with a grant from the United Engineering Foundation, developed a guide to the set of skills necessary for success in the engineering community -- Knowledge – Skills – Abilities — needed for all disciplines.Various engineering societies are now writing the Tier 5 occupation-specific requirements. The Competency Committee is charged to write concise and discipline-specific mining engineering, mineral processing engineering, geological engineering, and geophysical engineering by Sept. 30, 2017."

May 1, 2016

By Lana Alagha, Fardis Nakhaei, Jose L. Corchado-Albelo, Noelia Munoz-Garcia, Michèle Heitz

Sulfide tailings from past and present mining activities are important hosts of critical elements and precious metals. This review paper presented a literature survey on the recovery practices of some critical minerals containing Te from sulfide tailings with a special focus on the physical beneficiation and hydrometallurgical separation methods. Finally, a conceptual framework and possible processing flowsheets were proposed. The findings of this review will be useful for the researchers in the field of geochemistry, mineral processing, and metallurgy to evaluate the separation processes for reprocessing of mine tailings for the recovery of critical minerals.

Feb 1, 2024