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By A. P. Das

Biomining technology focuses on achieving effective recovery of precious metals from their ores and concentrates using microbial techniques. Biomineral extraction of manganese from low-grade manganese ores using bioleaching was investigated in this paper. Five fungal strains were selected for screening of bioleaching of low-grade Mn ore collected from Sanindpur iron and manganese mines, Koira Sector, Keonjhar, Odisha, India. A fungal strain, Aspergillus niger was selected as it showed high efficiency of manganese leaching. Growth of the fungus was determined in terms of sbiomass dry weight and the final pH was monitored. The selected fungal strain was used for bioleaching of low-grade manganese ore of -150µm size particle size at 2 % pulp density with 2g/100ml sucrose concentration for duration of 20 days. About 60 % of Mn bioleaching was obtained with A. niger. The fungal species proved to be useful for manganese biomining.

Sep 1, 2012

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

In order to realize the resource utilization of spent hydrodesulfurization catalyst, a solvent extraction-oxalic acid precipitation process is studied in this paper for efficiently recovering vanadium, nickel, and aluminum from the acid leaching solution of spent hydrodesulfurization catalyst. The process conditions for extracting vanadium with Cyanex 272 and precipitating nickel using oxalic acid as a precipitation agent were explored in detail. The results show that vanadium (IV) in the sulfuric acid medium containing nickel and aluminum was efficiently and selectively extracted by Cyanex 272. After three-stage countercurrent extraction, the extraction efficiency of vanadium was 99.76%, and the co-extraction efficiencies of nickel and aluminum were only 2.47% and 1.87%, respectively. Thermodynamic calculation shows that the extraction of vanadium (IV) from the sulfuric acid medium with Cyanex 272 is an endothermic reaction. The innovative method of oxalic acid precipitation was used to recover nickel from the raffinate, achieving selective extraction of nickel from the solution containing a high concentration of aluminum. The precipitation efficiency of nickel was 98.58%, while that of aluminum was only 0.75% under optimal conditions. The proposed flowsheet for the separation of vanadium, nickel, and aluminum from acid leaching solution may provide a new idea for the comprehensive recovery of valuable metals from spent hydrodesulfurization catalyst.

Nov 30, 2022

By Zdenek D. Hora

British Columbia is an important producer of a variety of industrial minerals for both domestic and export markets. Some commodities such as limestone, dolomite, gypsum, calcium carbonate, silica, barite and magnetite are raw materials for well-established industries located in British Columbia, Alberta and northwestern USA. Others, like magnesite, sulphur, jade, asbestos, dimension stone and clay products, are mainly exported in processed form to overseas customers. Companies are developing markets for relatively new mineral products, including pumice, volcanic cinder and zeolites. A number of attractive geological targets have been identified by industry while research by government geologists has outlined the potential for refractory minerals, gemstones, garnet, nepheline syenite, carbonatites, residual kaolin, igneous apatite and peat.

Jan 1, 2001

By Biswajit Samanta, Pranjal Pathak

This article presents a customized genetic algorithms (GA) with new crossover and mutation operators to solve the short-term production scheduling problem of multi-mine mineral value chains (MVC). The preceding problem consists of determining the extraction sequence and destination allocation of blocks from all the mines collaboratively while closely meeting the quality and quantity requirements of the processing units subject to relevant technical and operational constraints. The short-term production scheduling is carried out at shorter scales wherein the operations are modeled in a great detail with large number of constraints. This makes the industry-scale instances of the problem computationally intractable for standard mixed-integer programming (MIP) solvers. Thus, a GA-based heuristic approach is developed to obtain nearoptimal solutions to the large-scale instances of the problem in a reasonable amount of computational time. Computational experiments show that the developed GA-based method is a promising way to handle industry-scale instances of the problem. Moreover, the sensitivity analysis on various parameter combinations of crossover and mutation operators indicates that the customized global mutation operator, when used in combination with the customized crossover operators, took on average 12.5% less time than the customized local mutation operator to converge to a solution.

May 21, 2022

By Joseph Sawicz

By now, the concept of remotely controlling heavy equipment in underground mines has become commonplace. Personnel safety is the biggest justifier for remote control, followed by an inherent cost saving (in certain cases) when wireless video is added to the mix. There are a handful of vendors targeting this need, and for years the mines have remained loyal to their brand. But as the number of remote-control related accidents and maintenance costs increase it forces our industry to take another look at this commonplace concept. And as the blinders are taken off, the mines are getting the revelation that not all remote control systems were created equally. This paper highlights the differences between various remote control systems, and then moves into an in-depth look at HARD-LINE?s package which drastically cuts maintenance costs, and also provides a solid investment toward full Tele-operation.

Apr 1, 2005

By Stephen Semeniuk

Working with junior mining companies as a valuer, my experience with regulators is that simplicity works and the sales comparison method is the way to go. What I like about Mr. Ellis?s approach (as in his Table 7) is the integration of commodity prices with the timing of acquisitions and the implication of price changes in gold on the adjustment of individual project valuations. However, the sample gold-related appraisals in Ellis?s paper are pre-2008 transactions and readers should be made aware of the current market for such projects. Before moving on, to be noted is that the effective date of the Las Brisas appraisal (Ellis?s sample Appraisal 3) is Feb. 10, 2006; given that the subject value of Transaction 9, Choco 10 in Ellis?s Table 6 was listed as $353 million for a 95% interest in the con-cession, I am uncomfortable accepting that the acquisition was suddenly worth the adjusted value of $1,205 million (as given in Ellis?s Table 7). In some cases, illiquidity discounts can apply, and commodity-wise, in the one-month period between the acquisition in January 2006 and the adjustment to the Las Brisas conditions as of February 10, 2006, the indicated gold price change was only 41 cents/g ($12.60/oz); i.e., from $17.50/g to $17.91/g ($544.40/oz to $557/oz).

Jan 1, 2012

By J. P. Morgan

The Vesta Preparation Plant of the Jones & Laughlin Steel Corporation is located on the Monongahela River, eight miles south of Brownsville, Pennsylvania. This plant is capable of cleaning 2400 NT/hr of a mixture of Pittsburgh seam high volatile coals from the Vesta and Shannopin mines to produce a metallurgical coal of 6.75% ash and a steam coal containing 14% ash. Heavy media vessels are utilized to upgrade the coarse coal while launders and tables. handle the -1/4" fraction of the raw coal feed. Cleaned -coal goes to boot classifiers where the +48 mesh material settles and is removed by bucket elevators. This 1/4 x 48 mesh material is then sent to centrifugal driers for dewatering. As designed, the minus 48 mesh fraction overflows the boot as a 7 to 8% solids slurry and is recovered by cyclones and a thickener and dewatered by filtration. The-products of the heavy media circuit, the launder-table-boot-drier circuit and the cyclone-thickener-filter circuit are combined to constitute the shipped metallurgical coal. This Vesta-Shannopin mix is combined at J&L's Pittsburgh and Aliquippa Works with purchased low and medium volatile coals for the production of metallurgical coke.

Jan 1, 1962

By Earl L. Phillips

The Bureau of Mines conducted laboratory tests on samples of pozzolaniccement concrete to develop a low- strength backfill . Results show that support costs can be lowered by replacing a portion of the portland cement in mine backfill with pozzolan ( fly ash ) and lime . Unconfined compression tests on various ratios of fly ash to cement in 84 samples produced compressivestrength curves that can be used to estimate the best backfill mix for any mine .

Jan 1, 1964

By Kenneth Williams

Cargas a granel, incluindo finos de minério de ferro, devem ser embarcadas de acordo com as diretrizes acordadas entre os membros da Organização Marítima Internacional (IMO). Uma medida de segurança crítica é o Limite de Umidade Transportável (TML), exigido para cargas do Grupo A (cargas que têm tendência à liquefação). Diversos acidentes com navios envolvendo finos de minério de ferro da India, cuja causa suspeita-se ser a liquefação da carga, trouxeram à atenção o tema do TML de finos de minério de ferro. Um trabalho extenso de pesquisa foi desenvolvido pelos principais produtores de minério de ferro da Austrália e do Brasil para dar suporte à IMO no desenvolvimento de normas para o embarque desse tipo de material. Com essa finalidade, mineradoras patrocinaram o projeto AMIRA P1097, que foi conduzido pela TUNRA Bulk Solids (TBS) e o Centre for Bulk Solids and Particulate Technology (CBSPT), CSIRO e a Universidade de Auckland, com a gestão do projeto sendo feita pela Creative Process Innovation, a fim de estabelecer uma abordagem modificada de testes de TML específica para finos de minério de ferro. Esse estudo deu suporte aos resultados dos testes e conclusões do Technical Working Group do IMO, que publicou suas conclusões e descobertas em Setembro de 2013.

Aug 16, 2017

By SAMUEL GOMPERS

THE name engineer makes a very strong appeal to one who appreciates the mechanism underlying the fabric of our civilization. Engineers are scouts of civilization. We send them ahead into the lone 'places-the wilderness, the jungles, the great watery expanses, to build the highways necessary for civilized man. The engineers must deal with Nature, with that mysterious dynamic thing we call "force," with materials. It is their function to direct the human activity necessary to coordinate these forces and material in order to make them serve the needs and aspirations of men. Because of my high conception of the engineering profession I was glad to accept the invitation to address The American Society of Mechanical Engineers to voice my understanding of the possibilities of your work as engineers of industry, and to suggest what seems to me the responsibility of the-engineer to the whole modern industrial system.

Jan 1, 1921

By Christian Heili

In 1991 the Government of the Republic of Zambia passed legislation providing for the privatisation of Zambia Consolidated Copper Mines Limited (ZCCM). The newly formed Mining Companies, established after nearly a decade of difficult and protracted negotiations on such matters as, cash at close; retained percentage interest by ZCCM; equity investment; future investment commitment and tax concessions, were faced with great internal challenges and a harsh external environment. There was a convergence of a number of negative forces that had and will continue to have an impact on the mining environment in Zambia. The most crucial of these being, the competitive pressures of the global economy, fluctuating copper price and the prevailing HIV/AIDS pandemic. In the short period after privatisation, the Industry has seen the collapse of Binani Industries (Luanshya Mine), the withdrawal of Anglo America Corporation from Konkola Copper Mines Plc and the disposal of Chambishi Cobalt and Acid Plants by Anglovaal Mining Ltd. The objective of this paper is to provide a theoretical and practically researched foundation, which may be used to assist Zambian Mining Companies in making informed decisions on the issue of Strategic Outsourcing and the degree to which this may support the successful and sustainable growth of the Zambian Copper Mining Industry. If judiciously implemented, Strategic Outsourcing has the potential to generate a practical business valuation and process to assist Mine Management in the achievement of their business goals and consequently the return on investment to their Shareholders.

Jan 1, 2005

By T Nassis, P Louw, M R. Fry, T du Toit

Business intelligence (BI) and business analytics (BA) are established IT technologies that are used extensively in the business environment. This paper discusses the use of these technologies in production environments and beneficiation plants.Assmang’s Khumani mine is an iron ore operation located in the Northern Cape, South Africa. Assmang Limited is jointly owned by African Rainbow Minerals Limited and Assore Limited. This paper presents a case study of a BI solution applied to this plant, which is used by metallurgists, supervisors and all levels of operations and management to extract and analyse data to control and optimise the operation of the plant.The main advantage of adopting an established BI solution is the ease with which production personnel can extract and analyse data. The data is easily presented in familiar spreadsheets and no IT staff or specific training is required to achieve this.The solution adopted at Khumani mine uses a data mart with a multidimensional model (called an online analytical processing (OLAP) cube) acting as the main repository and source of data. The OLAP cube simplifies the access and analysis of plant data.The OLAP cube stores data in a specifically-designed way, which allows extraction and analysis to be performed quickly. It is designed to hold large amounts of data on a long-term basis, which could be for the life of the plant. It also performs automatic aggregations over many dimensions on a background process.A major benefit in adopting such a BI solution is that it allows common BA methods to be applied. This is due to both the efficient long-term storage of data and the availability of standard BA tools. BA tools are now able to perform data mining, predictive analytics, forecasting and other machine-learning algorithms. This paper presents the possible use of such advanced data analysis methods in a beneficiation plant.CITATION:Fry, M R, Nassis, T, Louw, P and du Toit, T, 2015. The use of common business intelligence and analytics tools in the operation and optimisation of iron ore process plants, in Proceedings Iron Ore 2015, pp 129–138 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Wi11iam I. Rau

In the recent past, there have been numerous projections of the capital requirements for additional mine and processing capacities required to meet projected non-Communist World demand for minerals during the next 15 years. A consensus judgment would place this currently at $14 billion per year, with the largest expenditures required for increases in aluminum and copper production. Until the early 1960's, internally-generated funds were used to finance nearly all of the large mining companies' capital requirements. Since that time, however, the enormous rise in capital costs per ton of capacity, accompanied by a relative stagnation in the financial condition of many of the major mining companies, have caused the industry to begin to rely on external sources for financing expansion, most notably, project financing from commercial banks and institutional lenders. Seven years ago, it was estimated that, in the five-year period 1972-1976,75% of the total capital requirements of $10 billion per year would come from internally-generated funds, with the balance to be provided by external sources. l There is little doubt that, in the coming decade, the percentage provided by external sources will increase. There should be little difficulty in attracting the necessary investment within the U.S., particularly in view of the expected continuation of companies in diverse industries seeking mineral investment opportunities. The more serious question lies in the availability of internal and external sources of funds for the expansion of mine and smelting capacity in the developing countries. Recently, R. F. Mikesell projected an average annual investment of $4.7 billion (in 1977 prices) over the 1977-1990 period would be required from foreign sources to expand metal producing capacity in developing countries. Mikesell concluded that external financing of mining projects in the developing world has averaged less than $1 billion per year over the past five years, thereby requiring more than a quadru1ling of this financing over the next decade.

Jan 1, 1978

By Juan J. Monsalve, Nino Ripepi, Richard Bishop, Jon Baggett

"Terrestrial laser scanning (TLS) is a useful technology for rock mass characterization. A laser scanner produces a massive point cloud of a scanned area, such as an exposed rock surface in an underground tunnel, with millimeter precision. The density of the point cloud depends on several parameters from both the TLS operational conditions and the specifications of the project, such as the resolution and the quality of the laser scan, the section of the tunnel, the distance between scanning stations, and the purpose of the scans. One purpose of the scan can be to characterize the rock mass and statistically analyze the discontinuities that compose it for further discontinuous modeling. In these instances, additional data processing and a detailed analysis should be performed on the point cloud to extract the parameters to define a discrete fracture network (DFN) for each discontinuity set. I-Site Studio is a point cloud processing software that allows users to edit and process laser scans. This software contains a set of geotechnical analysis tools that assist engineers during the structural mapping process, allowing for greater and more representative data regarding the structural information of the rock mass, which may be used for generating DFNs. This paper presents the procedures used during a laser scan for characterizing discontinuities in an underground limestone mine and the results of the scan as applied to the generation of DFNs for further discontinuous modeling.INTRODUCTIONAccording to the Mine Health and Safety Administration (MSHA), between 2006 and 2016, the underground stone mining industry had the highest fatality rate in 4 out of 10 years, compared to any other kind of mining (MSHA, 2016). Additionally, during that same time, 40% of the fatalities were due to ground control issues, such as roof and rib collapses and pillar bursts. The National Institute for Occupational Safety and Health (NIOSH) developed guidelines for designing underground stone mines (Esterhuizen, Dolinar, Ellenberger, and Prosser, 2011). However, these guidelines do not apply to all underground stone mines.Monsalve, Baggett, Bishop, and Ripepi (2018) present a case study of an underground limestone mine experiencing a structurally controlled mode of failure. The authors analyze different methods to study that type of instability. They conclude that the integration of terrestrial laser scanning (TLS) with discrete element modelling (DEM) can be used to prevent rock falls in underground excavations to enhance worker safety. However, an adequate rock mass characterization and structural mapping must be performed in order to generate reliable models that allow the engineer to have a better understanding of the rock mass behavior."

Jan 1, 2018

By Mahmoud Sepehrmanesh, Verya Nasri, Maziar Partovi

"This paper presents an assessment of the impact of tunneling and its associated risks on pile foundations located in the influence zone of tunneling operation. Tunneling in proximity of pile foundations introduces deformations in piles and in turn induces additional axial and bending forces. In modern mechanized tunneling, ground convergence is controlled through balancing the earth pressure at the tunnel face as well as applying pressurized bentonite through the shield. Reducing ground deformation can consequently lower the additional deformations and forces developed in the pile foundation and lessen the associated construction risk. In this paper, comprehensive detailed finite element modeling was performed to quantify the effect of the different parameters on induced forces in piles. Finite element models took into account the nonlinear behavior of soil and pile-soil interface. The modeling results are of practical importance in risk evaluation of tunneling in vicinity of pile foundations. INTRODUCTION Tunneling operation in congested urban areas becomes more frequent as demand for further utilizing underground spaces grows. In urban settings, it is not uncommon for tunnel designers to plan a tunnel route in close proximity to other structures to satisfy other competing objectives like raising the alignment to reduce excavation volume. Setting the alignment close to existing structures increases the risk involved in the project. It is the responsibility of the designer to thoroughly identify, assess, and mitigate all design risks involved. In this paper, we focus on the aspects involved in tunnel construction in proximity to existing pile foundations. Tunnel operations introduce deformation in the soil mass. Consequently, a pile located within deformation zone experiences extra forces as a result of the imposed deformation. The developed forces and bending moments can be in orders comparable with the pile capacity depending on the relative horizontal proximity of the tunnel and the relative depth of tunnel with respect to the pile length."

Jan 1, 2016

By Frederic Souche, Andrew R. Klaetsch, Brian Hann, Nick Goodenow

This paper describes support of excavation (SOE) design and construction for three large diameter shafts excavated through glacial soil and controlled blasting in complex sedimentary rock formations. SOE in soil consists of unreinforced secant pile rings designed to resist lateral pressure in circumferential compression, eliminating costly steel core beam reinforcing. Controlled blasting at the shafts, adits, and tunnels in densely populated neighborhoods requires managing risks to the public, buildings, and utilities. Controlled blasting approaches limited adverse impacts to receptors nearby while achieving adequate production and fragmentation. A site-specific observational approach was used to adjust blasting parameters, limiting the impact on local stakeholders while maintaining daily progress and managing overbreak.

Jun 13, 2023

By Alexander Blatt, Franz-Werner Gerressen

Diaphragm wall technique is usually used to construct structural elements in the ground, commonly used for retention systems, permanent foundation elements or deep groundwater barriers, named Cut-Off-Walls (COW). Recent developments proof, that the technology also satisfies the demands for using the diaphragm wall technique for bulk sampling purposes. Such kind of new ideas required the adaption of equipment and tools for a depth capability never reached before by a trench cutter in any commercial application worldwide. Compared to the development of increasing depths, especially inner-city applications with limited space, demand a minimization of equipment to accommodate such projects. The paper will focus on the developments and solutions generated to fulfill these requirements and will give an outlook to future developments. Further it describes finalized reference projects and will give a general outlook on future trends and developments. The Paper/The Presentation explains as well the installation process in general.

May 1, 2022

By C. R. Mambote

Vanadium is an important metal that is used mainly in ferrous and non-ferrous alloys due to the high tensile strength, hardness, fatigue resistance and corrosion resistance. Vanadium consumption in the steel industry represents about 85% of the vanadium-bearing products produced worldwide. The primary sources of the metal are patronite, roscoelite, and mottramite. Vanadium has also been produced as a by-product of the uranium production program which uses carnotite ores as a source of uranium. Vanadiferous magnetite iron ores are used for producing vanadium as well. In addition, it is known that vanadium can be recovered from the ashes of crude oil and petroleum coke. The process for treating boiler residues, fly ash and petroleum coke is similar to the process used to treat spent catalysts and ores. However, some of these materials may contain high carbon that must be removed at specific stage of the operation. Several processes are available for obtaining vanadium from fly ash, such as roasting vanadium bearing materials in the presence of sodium salt. The salt roasted calcine is subsequently leached with an alkaline or acidic solution. To obtain a cal-cine from which the vanadium can subsequently be recovered, the carbon in the source materials has to be eliminated prior to the roasting process. Other processes use the conventional hydrometallurgical route, in which fly ash is leached with sulphuric acid to obtain an impure vanadium pentoxide. The impure vanadium pentoxide is then treated with a sodium carbonate solution under atmospheric conditions to subsequently precipitate vanadium as ammonium metavanadate. Actually, the salt roasting process is the only process used commercially. In the present study, the progress in the technology of vanadium extraction from secondary materials is reviewed. The perspectives and the challenges for new process development are discussed.

Jan 1, 2014

By R. C. Anderberg, F. J. Caervenyak, F. J. Frattali, H. J. Kandiner, R. A. Brown

"INTRODUCTION Considerable interest was shown .prior to and during World War II in the winning of metallurgical-grade alumina from anorthosite, kaolin, siliceous bauxites, diasporic clays, and other aluminum-bearing ores. Laboratory and pilot-plant investigations were made on many of these ores by the Bureau of Mines, and a series of reports on them is being prepared. This report covers the tests made on the application of the lime-soda-sinter process to anorthosite, which is a mixture of albite, NaAlS1308, and anorthite, CaAl2Si208. Extensive deposits of anorthosite occur in the Laramie Range in Wyoming and extend into Colorado; other deposits are found in New York, with outcroppings appearing in Vermont, Maine, and Labrador.Anorthosito can not be treated by the Bayer process for the production of metallurgical-grade alumina, because excessive losses of soda and alumina occur from the formation of sodium-aluminum silicate due to the large amount (50 percent) of silica in the ore.RESULTS OF INVESTIGATIONSSmall-scale laboratory tests supplemented by pilot-plant runs have demonstrated that the alunina and soda occurring in the Wyoming anorthosite from the Laramie Range can be extracted and recovered satisfactorily by the lime-soda process. It has been shown that liquors containing approximately 95 gram of A1203 per liter can be consistently produced at Na20:A1203 ratios from 1.75 to 2.27, and that these liquors can readily be desilicated and carbonated to yield high-grade alumina trihydrate of quality comparable to that essential for cell-grade alumina. The optimum results were obtained with Na20:A1203 mol ratio of 1.03 and Ca0:Si02 ratio of 2.14 in the sinter when calcined at an average temperature of 2,444ºF. for 25 minutes."

Nov 1, 1947

By Seth C. Schaefer

As part of the Bureau of Mines, U.S. Department of the Interior, effort to provide thermodynamic data for the advancement of minerals technology, the Gibbs energy of formation of sphalerite (zinc sulfide) was investigated with a high-temperature galvanic cell employing stabilized zirconia as the electrolyte. In the temperature range 948 to 1,210 K, potential measurements were obtained for the cell Pt, ZnS + ZnO, S02 = 1 atm // Zr02 // Cu20 + Cu, Pt, with the overall cell reaction ZnS(c) + 3 Cu20(c) = ZnO(c) + 6 Cu(c) + S02(g). (1) These results, combined with the best available values of ?Gf° for ZnO, S02, and Cu20 from the literature, give the Gibbs energy of formation of zinc sulfide for the reaction Zn(l,v) + 1/2 S2(g) = ZnS© (2) ?Gf° = -64.223 + 24.02 X 10-3T ± 0.650 kcal/mole (3) (948-1,180 K; standard states - pure liquid zinc and S2 gas at 1 atm), and ?Gf° = -92.720 + 48.17 X 10-3 ± 0.650 kcal/mole (1,180-1,210 K; standard states - pure zinc vapor and S2 gas at 1 atm). A third law analysis yields for the formation reaction Zn(1) + 1/2 S2(g) = ZnS(c), (5) a standard enthalpy of formation as follows: ?Hf298.15 = -63.64 ± 0.700 kcal/mole.

Jan 1, 1978