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By HONGWEI YANG, Lili Zhang

Copper slag is mainly used in cutting tools, abrasives, asphalt pavement, road construction, and in the production of concrete as an alternative to sand and cement [1]. As a renewable resource, only about 15-20 percent of the slag is used for these applications, and the dumping or disposal of surplus unused slag results in waste of a certain amount of usable metal in the feedstock [2]. In this work, the oxidation behavior of copper smelting slag under nonisothermal condition is studied using data obtained by the thermogravimetric (TG) method, and the kinetics parameters and reaction mechanism of oxidation are determined. It provides a theoretical basis for the comprehensive recovery of iron resources in slag and the selection of reasonable slag-making conditions.

Oct 1, 2022

By Y. Pan, P. Tukkaraja, R. BHARGAVA, V.V.S. VYTLA, S.J. SRIDHARAN

Panel caving is an underground bulk mining method that uses gravitational force to mine massive, steeply dipping and deep-seated ore deposits at lower operating cost. To control dust and gas emissions entering the production level during the extraction of ore from the draw points in a panel cave, relatively negative pressure is created in the cave by installing an exhaust fan in the exhaust drift located on top of the cave. As caving is a dynamic process, designing an effective ventilation system is challenging; therefore, estimating the airflow resistance offered by the broken rock inside the cave is critical. This study investigates the effect of changes in the bulk porosity of the broken rock on the cave airflow resistance using the computational fluid dynamics (CFD) approach. The results show an inverse relationship between the cave airflow resistance and the bulk cave porosity. The pressure-quantity characteristic curves presented in this paper provide valuable information for sizing and operating an exhaust fan used for a mature panel cave ventilation.

Nov 1, 2022

By Dan Brunner, Scott Thomson, Ben Lyddall, Duncan Thomson

Geosensing is used in oilfield drilling in conjunction with geophysical tools to support characterization of rock properties, geology, and reservoir conditions. This technology is now available to the mining industry and has been successfully applied to underground in-seam directional drilling in Australian coal mines for geologic exploration and methane drainage. The system utilizes a range of drill rig and wellhead mounted sensors which, combined with analytical software, produce real-time data from which 3D spatial features can be accurately modelled significantly in advance of mining. This innovation greatly expands on the information obtained from current in-seam directional drilling practices and provides for improved characterization of coal seams, including soft and weak zones, locations of geologic discontinuities, and analysis of formation flow. This paper provides a description of the geosensing system and the interpretation of actual data from long in-seam directionally drilled methane drainage boreholes at mines in Australia, and discusses how this system increases the value of directional drilling as an exploration tool for the coal mining sector, and the evaporite and hard-rock mining sectors where directional drilling is also applied.

Feb 1, 2024

By Anand Kumar, Debasis Deb, A. K. Mishra, M V. N. S. PRASAD.

In the Adriyala project, shield-leg pressure data from all shields and shearer location with time stamp from a mechanized longwall face are monitored and recorded in a surface computer. The data contain random noise due to power failure, leakage of legs, bad sensor readings, and other maintenance or geomechanical problems. An algorithm has been developed to detect mining cycle parameters such as setting and final pressures and duration of the cycle from these data for the analysis of periodic roof weighting phenomena. The intensities and persistence of periodic roof weighting are vital information for mine management to make judicious decisions on longwall operation.

By Barbara J. Arnold

Combat Infantrymen’s Badge and Bronze Star Medal. Following his discharge from the Army, he re-entered SDSM&T in 1946 and earned a B.S. degree in Metallurgical Engineering in 1948. He then received an M.S. from Montana Tech (MT), worked several years in industry and then as an Assistant Professor at the University of Washington (Seattle). He joined his Montana Tech colleague, Douglas W. Fuerstenau, at The Massachusetts Institute of Technology (MIT), receiving his doctorate in 1957. While at MIT, he married Clare M. Donaghue of Dorchester, Massachusetts, in 1955

Jan 3, 2022

By Eckl, Martin, Stefan Lemke, Martin Londschien

"Tunnels are built with a design life expectancy of over 100 years. One key component of such a design is the waterproofing system, which must reliably fulfil its function during the whole service lifetime of the tunnel structure. This paper deals with the determination of test criteria for the durability assessment of geosynthetic products in tunnel sealing systems. Hereby the understanding of the individual aging processes is crucial along with the long-term experience with these materials to ensure the transfer of the laboratory results and performance to site practice (test calibration) and vice versa. To verify the results of the new test procedure the material properties of geosynthetic products samples removed from older tunnels are investigated. Based on the presented results of the still ongoing research programs some preliminary conclusion regarding the updating of regulations for tunnel sealing systems are given. INTRODUCTION Watertightness is directly related to the durability and serviceability of the concrete lining. Therefore, modern traffic tunnels and shafts (Figure 1) are generally protected against mountain/ground water and water penetrating through rock fissures by a sealing system, for example with a loose-laid polymeric sheet membrane. Hereby the waterproofing sealing systems must be reliably fulfilling their function during the whole service life of the tunnel structure, regularly of more than 100 years. In consequence, the quality and lifetime performance of the waterproofing materials—beside the correct professional and careful installation in a tunnel infrastructure, is of great importance. The challenge for the industry, owners, operators and designers is ultimately the development of qualification testing and requirements (acceptance criteria) for products to ensure the design lifetime performance. Hereby the qualification procedure is seen as a routine integrated in standards, norms or guidelines, wherein test procedures should cover typical environments for the specific application fields. Polymeric synthetic raw materials are increasingly used in products with long service lifetimes (e.g. in injections, gaskets, waterbars, spray-applied and sheet waterproofing membranes). During service they are subjected to chemical (e.g. oxidation processes) and physical (e.g. changes in morphology) influences from the environment, which affect their mechanical properties—and they age. Hereby organic materials are more affected than inorganic materials. Also, polymers show strongly temperature-dependent properties compared with other construction materials. However, their long-term aging behavior is not given per se and has to be explored extensively by suitable tests, which simulate—under accelerated processes—real exposures and loads. Hereby the understanding of the individual aging processes is crucial along with the long-term experience with these materials to ensure the transfer of the laboratory results and performance to site practice (test calibration) and vice versa."

Jan 1, 2016

By J. Sohn

The most promising near-term alternative to fuel cell driven vehicles is probably Hybrid Electric Vehicle (HEV or EV) technology. HEV technology combines the best characteristics of fuel-driven engines, electric motor drives, and energy storage components. It is designed with a combustion engine that functions as the primary power source, and an electric power storage system that functions as the secondary power source. The presence of the secondary power source allows designers to size the combustion engine for cruising power requirements. A new energy source for HEV or EV market will become lithium ion batteries (LIBs) in the near future. LIBs for HEV or EV has large scale about more 10,000 times than small size one for IT devices in order to achieve high electric density/capacity and high efficiency, etc. In those reasons, physical treatment of the batteries is more difficult for stable dismantling in comparison with the smaller one. Hybrid vehicle sales will grow by nearly 400 percent during the next seven years, according to a new report from analyst firm ABI Research. By 2013 hybrids will make up 6 percent of annual U.S. auto sales. The traction battery pack will become air-cooled LIBs which consists of several modules of Li ion battery and connected in series/parallel configuration to provide about >450 VDC, >150 kW peak power, and >80 Ah capacity. As the use of these batteries tends to increase significantly for the next years, it is relevant issues that development of new recycling methods as well as optimization of existing processes to treat spent LIBs for HEV have being addressed in order to obtain sustainability. In this study, physical treatment containing stable electrical discharge of spent LIBs for HEV was carried out for recovery of valuable metals from the batteries. Also In order to increase the yield of valuable metals through physical treatments such as electric discharge of spent batteries, crushing, and classification, we also focused on the recovery of cobalt from +8 mesh fraction due to its large portion in crushed intermediates.

Jan 1, 2010

By AJIT SWAIN, SUNATI MOHANTY

The ability to predict the dewatering performance of an industrial hydrocyclone from a laboratory-model hydrocyclone is of great importance. In this study, laboratory-scale hydrocyclone experiments were conducted using silica sand samples at 10 percent solid concentration for dewatering with Mozley hydrocyclones with diameters of 2 in. and 4 in. The objective is to predict the design parameters for an industrial dewatering cyclone to achieve higher solid concentration in the underflow. A model was developed based on the Nageswararao hydrocyclone model with the help of a commercial simulator for a hydrocyclone operating at 100 t/h and 20 percent solid concentration to achieve 80 percent solid recovery at 45 percent solid concentration in the underflow.

Mar 1, 2023

By C. Cardoso, G. Bermudez, A. Jalili

Bigger flotation cells can result in larger froth surface areas and longer froth transport distances, this has been credited to impact froth recovery. Thanks to recent advancements, the newer flotation machines can be designed with different launder and crowder arrangements to enhance froth management. Nevertheless, lower head grades, complex ores and even larger mechanical flotation cells can lead to insufficient froth collection, even if the cell is equipped with the most recent flotation advancements like the center launder design. Aforementioned issue can become critical at the end of the flotation row. Increased crowding has been proven to be a solution to overcome inadequate froth recovery. However, scaling-up crowders for larger flotation cells can rise challenges, particularly in terms of structural limits and design for service. This paper presents the development journey for the Spider Crowder Upgrade, an advancement to improve froth collection in large flotation cells that are already equipped with center launders.

Feb 1, 2024

By M. Tapper

If one considers that prehistoric man's first house may have been a limestone cave, calcium carbonate may be the most timeless of all building materials. Fanciful history aside, CaCO3 has been used for countless applications in human habitats. After all, tine marble block and tiles have always been the hallmark of eloquents and style. Mortars and cements derived from limestone have held together the very blocks of our civilization. In modem times, synthetic polymers are blended with ground limestone to produce everything from pipe, floor tile, cultured marble and house siding. All of these miracles of our technology contain CacO3 of various sizes and in varying amounts. This paper will discuss some of the critical attributes of CaCO3 which make it suitable for the new building products that have helped increase our standard of living. The vehicle of discussion will be a residential, single family house.

Jan 1, 1993

By F. D. Huntley

Raw materials used by the Flat Glass Industry are known in the Industrial Minerals geology sector as Specialty Products. These pro- ducts must meet specification limits usually not the same for all glass manufacturers. Evolving new glass compositions will require mineral concentrates of consistent purity being produced within economic limits that will assure market viability of the resulting glass product. The amount of success the Flat Glass Industry will achieve by developing and maintaining domestic production centers will be determined by many economic factors which affect the costs of doing business. Technological developments by mineral processors must continue in order to achieve more efficient production of high quality glassmaking raw materials.

Jan 1, 1986

By S. L. Bessinger

In the design and specification of a ventilation system for an underground mine, it is necessary to make reasonably accurate estimates of the pressure losses in the various airways of the mine. These estimates can be made with little difficulty for open airways with simple geometric cross-sections, such as those cut by continuous miners or tunnel-boring machines. The situation is much different on a longwall face, where the airway's complex geometric cross-section and the presence in the airway of obstructing equipment having a variety of shapes make it difficult, if not impossible, to estimate pressure loss using traditional methods of calculation. Headlosses in mine entries are calculated using Atkinson's Equation (1). [H = (English) H = (SI) (1)] where H = pressure ,loss, in. of H20 (Pa) K = friction factor, lbf min2/ft"4(Kg/m3) P = perimeter, ft. (m) L = airway length, ft (m) Q = airflow quantity, ft3/min (m3/sec) A = flow cross sectional area, ft2 (m2)

Jan 1, 1987

By S. Amirshenava, S. Nadimi

"Premature and unplanned mine closure can result in significant adverse impacts on the environment and community and need to be managed appropriately. Risk management techniques can reduce the negative impacts and risks of early mine closure. Risk Assessment 3D Model, is an efficient tool to quantify risk. The aim of this paper is to identify the mine closure risks in Choghart iron ore mine, and calculate the overall mine closure risk level. The result shows that 51.4% of assessed risks have low risk level and the overall risk level of early mine closure is low. Keywords: mine closure, risk assessment 3D model, Choghart iron ore mine INTRODUCTION The modern mining life-cycle can be divided into three main stages; exploration, mining (opening and production) and post mining (mine closure, and reclamation). Mine closure is the critical component of the modern mining life-cycle and it refers to the period of time when the operational stage of a mine has permanently ceases (Heikkinen et al, 2008). Planned closure occurs due to the depletion of ore reserves, but sometimes it is premature. Laurance (2006) shows that only 25% of mine closure in the past 30 years was due to resource depletion and in 75% of the cases the mines were closed for the other reasons. Ghanbari et al (2010) demonstrated that 48.6 % of copper mine closure in the past 100 years was due to resource depletion and 51.4 % of copper mines have been closed due to other reasons. The main reasons of premature mine closure are as follow (Laurance, 2006; Ghanbari et al, 2010; Maiti, 2013): • Economic, (low commodity prices or high costs) • Geological, (over-estimation of grade and tonnage) • Geotechnical (adverse geotechnical conditions) • Technical (equipment failure) • Regulatory, due to safety or environmental breaches • Social or community pressures • Closure of downstream industry or markets • Flooding or inrush Minaei Mobtaker and Osanloo (2013) developed a mine closure prediction model based on the data collected from closed iron ore mines in the past 100 years. They showed that economic factors, exhaustion of ore reserve and geological conditions are the main reasons of iron ore mine closure. They treated mine closure as a decision making problem in order to predict the causes of mine closure, including the uncertainties of some mine plan parameter such as iron ore price, production and consumption."

Jan 1, 2016

"The mining industry suffers from a number of incorrect perceptions, one of which is that it is an outdated industry that has not changed for hundreds of years. But the truth of the matter is that mining is a vibrant, highly complex industry that not only employs highly skilled and educated professionals but is also often on the cutting edge of technology. It is an industry with projects that are ever-evolving and among the most challenging engineering feats in the world.Take for instance the U.S. 53 Highway Relocation project in Virginia, MN. While more of a civil engineering job than a traditional mining project, it is still a complex engineering challenge taking place in a mining environment that has called on the skills of eight state agencies, three federal agencies, a host of contractors and many consultants, including many from the local mining industry in the Iron Range of Minnesota.In 1960, the Minnesota Department of Transportation (MnDOT) constructed U.S, Highway 53 on a private easement owned by US Steel that cut across a massive taconite deposit. MnDOT constructed the highway with the agreement that if the highway needed to be moved to access the taconite deposit before 1987, US Steel would foot the bill. And if the move was required after 1987, the responsibility would fall to MnDOT. In 2010, MnDOT received the notice that the highway would have to move as property owner United Taconite planned to access the ore, setting in motion one of the greatest engineering challenges, and the highest risk project, in the history of the states’ transportation department.Pat Huston, U.S. Highway 53 Relocation project manager, opened the 90th SME Minnesota Section Conference in Duluth, MN on April 19 with a presentation about the project that includes 5 km (3.2 miles) of fourlane highway and a new 345-m (1,132-ft) bridge that will be the tallest in Minnesota when it is completed later this year.“This project was not business as usual,” Huston told the packed crowd. “Highway 53 connects Canada and the Iron Range to Duluth and Lake Superior. It is an important highway.”During his presentation he spoke about many topics that were familiar to the more than 1,100 mining professionals who attended the conference. In his keynote speech,"

Jan 6, 2017

By Jonathan G. Price

The 2011 report titled ?Energy Critical Elements: Securing Materials for Emerging Technologies? by the American Physical Society?s Panel on Public Affairs and the Materials Research Society surveys potential constraints on the availability of these elements and identifies five specific areas of potential action by the United States to ensure their availability: 1) federal agency coordination; 2) information collection, analysis and dissemination; 3) research, development and workforce enhancement; 4) efficient use of materials and 5) market interventions. Energy-critical elements (ECEs) are a class of chemical elements that currently are critical to one or more new energy-related technologies. A shortage of these elements would significantly inhibit large-scale deployment, which could otherwise be capable of transforming the way in which energy is produced, transmitted, stored or conserved. The report addresses elements that have not been widely extracted, traded or used in the past, and therefore are not the focus of well-established and relatively stable markets (such as carbon in coal or uranium as fuels, copper, aluminum, nickel and iron, all of which are clearly vital in energy applications).

Jan 1, 2011

By S. N. Groudev

A process for the combined chemico-biological removal of iron present as oxide minerals in different mineral raw materials (quartz sands, kaolins, clays, etc.) was developed. In the process, mineral raw materials are leached at about 90 °C with lixiviant containing microbially produced oxalic and hydrochloric acids. The leaching is carried out in mechanically stirred acid-resistant reactors for periods of from 1 to 6 hours, depending on the iron content and the forms of iron in the raw materials being leached. The iron contents of some sands treated by this method were lowered from levels that were in the range of 0.035% to 0.088% Fe2O3 to less than 0.012% Fe2O3, making them suitable for the preparation of high-quality glass. The iron contents of different kaolins were lowered from levels that were in the range of 0.65% to 1.49% Fe2O3 to levels in the range of 0.44% to 0.75% Fe2O3. As a result, the whiteness was increased from values of 55% to 87% to values of 86% to 92%. The iron content of clay was lowered from 6.25% Fe2O3 to 1.85% Fe2O3, and this increased the “fireproofness" of the clay from 1,670°C to 1,750°C. A similar process was used for the leaching of aluminum from aluminosilicates, mainly clays and kaolins. However, in this case, the microbial fermentation fluid containing citric acid was acidified by means of sulfuric or hydrochloric acid or by means of different mixtures of mineral acids. For enhancing aluminum solubilization, the aluminosilicates were heated before leaching at 600° to 650°C for 1 to 2 hours. Over 90% of the aluminum present in different clays and kaolins were leached within 3 to 6 hours. "Silicate " bacteria related to the species Bacillus circulans were used to leach silicon from low-grade bauxite ores containing aluminosilicates as impurities. The bacterial action was connected with the degradation of the mineral structures (by means of microbial metabolites such as organic acids and exopolysaccharides), as well as with the selective separation of the rich-in-aluminum fine fractions, which were retained by the mucilaginous capsules of the bacteria. The solid residues after treatment were characterized by higher values of alumina and silicon module (A1203: SiO2 ratio), and they were suitable for processing by means of the Bayer process for recovering aluminum. The bending strength and other ceramic properties of kaolins were improved by contact with well-developed cultures of "silicate" bacteria. The improvement was caused mainly by bacterial metabolites (exopolysaccharides) that acted as resins during drying.

Jan 1, 2000

By A. Dell’Era, E. Ciro, C. Lupi

The paper explores the recovery of indium via electrowinning from sulfate baths, focusing on the impact of different cathodic supports (AISI 316L and nickel) on process parameters such as electrolyte composition, current density, and temperature. The study compares productivity, morphology, and structure of indium deposits on both cathodes, finding that nickel cathodes generally yield better results.

Nov 1, 2023

By Zengwu Zhao, Peng Xu, Jieliang Wang, Qingwei Bai, Xinyang Liu, Xiao Lei

The paper investigates the capture and recovery of rare earth minerals from Bayan Obo ore using superconducting magnetic separation. A finite element model (FEM) was established to study the influence of various factors on the capture of rare earth minerals under a high-gradient superconducting magnetic field. The study aims to improve the efficiency of rare earth mineral separation and recovery.

Oct 1, 2023

By R. Miller

Lowering our globe’s emissions is a major effort as we move toward a future net-zero carbon environment requiring significant investment in a new, low-carbon infrastructure, along with key market incentives to change. Industry will play a key part in this transformation, requiring expertise in both energy and emissions. Key elements of the de-carbonization strategy are: energy data, emissions reporting method, governance, de-carbonization project generation and drivers, the MACC, electrification, and the de-carbonization checklist. For a zero carbon future, it will be key for business leaders to understand decarbonization, anticipate technological changes, and implement new business me

Mar 2, 2022

By Takahide Wakamatsu

In Japan all the complex sulfide ore deposits of base metals have been developed as underground mining. The underground mining cost is extremely high as compared with open pit mining case. Therefore, in milling section of base metal mines, technical advance for maximum recoveries of valuable constitutents in ore has been required all the time to utilize as much ore mined as possible. At present, in mill plants treating "Kuroko", complex sulfide ore, concentrates of copper, lead, zinc, pyrite and barite are produced, with gold and silver contents in the copper, lead, and zinc concentrates being estimated as extra profit. As in the case of Kuroko milling plants, gold and silver contents in the lead and zinc concentrates of lead-zinc ore milling plants are also varuable from an economical viewpoint. Silver content is very high in Kuroko crude ore as well as lead-zinc ore.

Jan 1, 1982