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By Natalia Konstantinova, Georgy Novikov, Pavel Rekant, Goergy Cherkashov, Olga Bogdanova

The economic interest of oceanic ferromanganese crusts and nodules is determined by high grades of major, rare and earth rare elements in these types of marine minerals [1]. Modern oceanic ferromanganese deposits have a global distribution with the largest fields in the Pacific Ocean. The Arctic Ocean still remains a poorly explored region. The first ferromanganese deposits from the deep part of the Arctic Ocean were recovered almost at the same time in 2012 both in US and Russian cruises to the Chukchi Borderland (1) and Mendeleev Ridge (2). Preliminary results of mineral deposits from the first area were reported at UMI-2012 by James Hein et al. [2]. We present here the data of ferromanganese deposits from the Mendeleev Ridge.

Sep 1, 2014

The extraction and processing of minerals from surface mines and quarries can produce significant fugitive emissions as a result of site activities such as blasting, unpaved road haulage, loading, primary crushing and stockpiling. Uncontrolled fugitive dust emissions can present serious environmental, health, safety and operational issues impacting both site personnel and the wider community. Simulation technology is finding increasing use for the purposes of advanced warning of potential problem emissions in addition to providing a basis for future planning applications where demonstrable compliance with regulatory requirements are necessary. The initial re-entrainment and subsequent dispersion of fugitive dust presents a process complicated by the combination of the in pit topography, the surrounding natural topography and the dynamic nature of emissions from these sites. These factors impact upon the accuracy and reliability of the conventional Gaussian plume based computational prediction methods employed for regulatory compliance and IPPC applications. This paper proposes that optimal modelling of open pit emissions may be more accurately achieved by the use of a multi-scale predictive modelling approach utilizing computational fluid dynamics (CFD) methods for high resolution near source dispersion and conventional Gaussian based methods for far field dispersion modeling. This paper presents a numerical based flow and dispersion analysis of a typical UK based open pit utilizing CFD in conjunction with a conventional Gaussian plume based methods. Typical operating emissions and meteorological conditions are obtained from long term data records collected at a large operating quarry extraction operation in the UK. Emissions are modelled using a Lagrangian framework within conventional atmospheric boundary layer (ABL) profiles expressed as functions of turbulence and velocity parameters under assumed neutral conditions. Results are presented in terms of the impact of site topography on in pit retention as compared to the Gaussian based method.

Jan 1, 2009

Your assessment of the minerals business. The global mining industry is strong. I am convinced it will continue meeting the mineral needs of the world population for the foreseeable future. Two developments have greatly enhanced the industry’s ability to produce low-cost minerals. Technological innovations have resulted in increased productivity. And there has also been a dramatic expansion of the number of favorable countries in which to explore and mine. Capital expenditures have flowed to the low-production-cost mines and development projects as well as to the exploration projects and stable countries having the best potential for valuable mineral discoveries.

Jan 1, 2000

By James W. Marold

Tunnel and shaft plugs have been designed to assist in construction of new and rehabilitation of existing tunnels and shafts. Tunnel plugs have been used to provide construction access for side by side tunnels, separation of raw and treated water, and to allow operation of one tunnel during construction of a nearby tunnel. Shaft plugs have been used to seal up surface openings to tunnels and to prevent seepage of water to the surface through adjacent tunnels or shafts. The design construction details of tunnel and shaft plugs are provided. Typical examples of tunnel and shaft plugs are provided.

Jan 1, 2008

By D. Mohapatra

Extraction of Al(III) from aqueous sulfuric acid solutions into organic Cyanex 272®-carbon tetrachloride systems was investigated from a multi-component mixture containing aluminum, cobalt and nickel. Al(III) extraction efficiency was quantitative with 1.0 M Cyanex 272® in two stages at an aqueous: organic (A:O) phase ratio of 1:1 and an equilibrium pH of 3.2. The stripping of Al(III) from the loaded organic (LO) with different acids indicated sulfuric acid to be the best stripping agent. More than 99% stripping of Al(III) from the LO was achieved using 2 M H2SO4 at an A:O phase ratio of 1:1 in a single stage. The stoichiometry of the extracted species of Al(III) was determined by the slope analysis method. The extraction reaction proceeded via the cation exchange mechanism and the extracted species was assumed to be AlA3?3HA, where HA refers to the dimeric and A the anionic form of the extractant, Cyanex 272®. The extraction of Al(III) was studied in the presence of various ions to ascertain the tolerance limit of individual ions.

Jan 1, 2008

By P. James

"INTRODUCTION Control of target stream acidity is widely used in MIW (mining influenced water). Tailoring pH (a measure of acidity) finds application for controlling key chemistry in both process and waste streams. Traditional lime addition for neutralization and precipitation is most often used but has high reagent costs and results in large amounts of mixed metal sludge requiring costly disposal. A new adaptation of BPS’s patented DEMET™ technology (Dynamic Electrolytic Metal Effluent Treatment) platform offers a potentially improved and “reagentless” alternative to traditional chemical addition for pH adjustment. Electricity rather than chemical addition utilized in BPS’s proprietary approach controllably tailors target stream pH. The method offers a simple, low-cost processing technique yielding cleaner treatment chemistry. BPS’s “green” approach may yield lower operating (OPEX) and life cycle costs and significant reductions (up to 50%) in sludge generation compared to conventional lime treatment. It can also allow new opportunities to generate revenue via selective recovery of valuable processing byproducts. Specific savings and revenues depend on the target site chemistries, details, and processing goals. A more detailed discussion of the process and its operational principles may be found in Reference One.[1] Here application of the BPS treatment to POx (Pressure Oxidation) leaching as an alternative to traditional chemical addition is examined. An example operation process flow for gold mining is considered.[2] Promising processing points for potentially replacing conventional processes with DEMET are noted. The possibilities for lowering OPEX costs, lessening sludge creation, and capturing various valuable byproducts and residuals are examined. Financial life cycle benefit estimates of the principal gains provided by DEMET application to the example operation are noted. Extension and generalization of the analyses to a wider range of scenarios is explored."

Jan 1, 2016

By J. R. Heberger

"“Safety Pays in Mining” web application developed by the U.S. National Institute for Occupational Safety and Health Mining Program, helps mines determine the potential costs associated with mining injuries. This web app groups injuries by type, either by the cause of the injury or by the nature of the injury. When the user selects one of more than 30 common types of mining injuries, the app provides information on the distribution of costs of workers’ compensation claims for that type of injury. Based on other user inputs, the app will estimate the total costs of the selected injuries, including an estimate of additional indirect costs, the estimated impact of total injury costs on mining company profits, and provide some examples of other items, such as services or equipment, on which companies could spend the savings that result from the prevention of injuries. This paper reviews the app by discussing its development, how it is used to show the true costs of mining injuries, and how mines can benefit from using it.IntroductionInjuries on the job cause pain and suffering. They can also profoundly affect profits and daily operations. In addition to paying direct costs or increased premiums for workers’ compensation insurance, a company might need to pay overtime for other workers to fill an injured worker’s job role, cover training costs for a replacement worker or divert administrative resources in the wake of an injury. “Safety Pays in Mining” is a web app that estimates the distribution of these injury costs and assesses the impact that occupational injuries have on a company’s profits.The costs of specific types of occupational injuries in mining are not readily available as mining and insurance companies do not usually share this information. As a consequence, companies only have cost information based on previous experience with their own employees. Therefore, if a mine never experienced a finger amputation for one of its miners, for example, it would not be aware of the possible costs associated with this type of injury. In addition, injury costs are unique in that the cost distribution is so wide that just using the average cost of a specific injury type does not provide adequate information. Some injuries involve immensely high costs, and even though the risk of these high-cost injuries occurring is low, mines need to be aware of the potential impact on their company’s financial health."

Dec 1, 2018

By William H. Langer

Large amounts of limestone fines co-produced during the processing of crushed lime-stone may be useful in the sequestration of carbon dioxide (CO2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point sources such as cement manufacturing. AWL reactants are readily available, inexpensive and environmentally benign. Waste CO2 is hydrated with water to produce carbonic acid. This reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate. AWL waste products can be disposed of in the ocean. Feasibility requires access to an inexpensive source of limestone and to seawater, thus limiting AWL facilities to within about 10 km (6 miles) of the coastline. The majority of U.S. coastal power-generating facilities are within economical transport distance of limestone resources. AWL presents opportunities for collaborative efforts among the crushed stone industry, electrical utilities, cement manufacturers and research scientists. There is a concern that CO2 generated from human activities is contributing to climatic and environmental changes. Approximately one-third of anthropogenic CO2 emissions come from burning fossil fuels to generate electricity. Each power plant is capable of emitting several million tons of CO2 annually. A variety of other industrial processes, such as cement manufacture, oil refining, and iron and steel production, also emit large amounts of CO2. The level of atmospheric CO2 can be reduced by capturing CO2 from point-source emissions and storing or sequestering it in isolation from the atmosphere (U.S. Department of Energy, 2003). In 1999, G.H. Rau and K. Caldeira proposed a geochemistry-based method that is referred to as accelerated weathering of limestone (AWL) in a paper titled ?Accelerating carbonate dissolution to sequester carbon dioxide in the ocean ? geochemical implications.?

Jan 1, 2009

By Paul C. Schmall, John F. Donohoe, Arthur B. Corwin, Derek Maishman

Ground freezing was utilized to provide complete stability of the excavation face and complete groundwater cut-off for the jacking of the three tunnel boxes for the Interstate 90 / Interstate 93 approach to the Fort Point Channel crossing. Through a wide range of geological conditions and large buried obstructions, the freezing provided complete stability of the face so that a 11.5 m (38 ft) high free standing vertical face could be mined without the need for any additional face support. Obstructions were incorporated into the massive frozen ground matrix, and held in place so that they could be excavated with a minimum of disturbance. The freezing provided an absolute groundwater cut-off, and permitted the work to be done without disturbance to the active rail system immediately above. With the use of instrumentation such as borehole thermocouples, the effectiveness of the freezing was guaranteed and the jacking proceeded with complete confidence and assurance of the ground conditions ahead.

Jan 1, 2001

By G. Kosick, G. Dobby

CEET, an acronym for Comminution Economic Evaluation Tool, was jointly developed by MinnovEX Technologies Inc. and 13 major mining companies for the purpose of designing and predicting the performance of grinding circuits. It fundamentally differs from other methods by using as its’ data set a geostatistically significant population of hardness data distributed across the mine block model. Historically the characterization of an orebody for the purpose of either designing a grinding circuit or predicting the performance of an existing circuit has been done with a relatively limited number of discrete samples. In addition to power selection, shell sizing, and costing for multiple circuit options, CEET also outputs tons per hour, P80, and operating cost on every mining block for subsequent integration back into the block model. This paper will provide an overview of what CEET is and how it works.

Jan 1, 2001

By J. Perlacia

"As the bulk handling sector continues its transformation to Industry 4.0, the mining industry, and its harsh working and environmental conditions, provides a perfect spot to study the feasibility of remote analysis and maintenance of the components used for bulk handling. The most important and expensive tools have been adapted to the digital era in recent years, from remotely controlled haul trucks to monitored conveyor belts.However, the big items of the installations rely on smaller parts that have been leftaside, mainly due to the difficultyof adapting them to the Internet ofThings (IoT).The paradigmatic example is the lack of monitored rollers, while all the other components of the conveyorbelt installations (the belt itself, motors, drums, etc.) were monitored some time ago. The main problem is that a failure of a single roller can cause the stoppage of the entire conveyor, due to possible damage to the belt. Thus, the implementation of an integral monitoring system of all the components of the conveyor is a must.The research and development department of ULMA Conveyor Components has been working since early 2012 on the development of monitored rollers, testing all the problems until their final installation in different demanding conditions, from the extreme heat in Australia to the freezing cold of Norway. All the tests have been done under actual working conditions, in real installations and have provided valuable knowledge in the identification of problems, their solutions and the final advantages of a roller monitoring system.Background and current stateThe malfunction of a single roller in certain conveyor belts can force the standstill of the entire installation until its replacement, due to the risk of greater and more expensive failures, such as a rip in the belt. In the case of a bulk handling installation, where a continuous supply of material is necessary, an unexpected stop of one hour could result in huge economic losses."

Nov 1, 2019

By Peter L. McSwiggen

The mineralogy of the Biwabik Iron Formation changes dramatically from west to east as the formation nears the basal contact of the Duluth Complex. This reflects a contact metamorphism that took place with the emplacement of the igneous Duluth Complex at tem¬peratures as high as 1200 °C. However, the mineralogy of the Biwabik Iron Formation also varies vertically through the stratigraphy of the unit. This variability in both the vertical and horizontal dimensions makes it difficult to predict exact horizons where specific minerals will occur. The iron-formation has been subdivided into four broad stratigraphic units (lower cherty, lower slaty, upper cherty, and upper slaty) and into four lateral mineralogical zones (1-4). Zone 1, the westernmost zone, is characterized by quartz, magnetite, hematite, carbonates, talc, chamosite, greenalite, minnesotaite, and stilpnomelane. The silicate mineralogy in Zone 2 of the Biwabik Iron Forma¬tion changes very little. However, the minerals begin to change dramatically in Zone 3. Most significantly, Zone 3 is characterized by the appearance of grunerite in both a tabular form and a fibrous form. In Zone 4, the original silicate minerals have completely reacted, and a new suite of minerals occupies the iron-formation. These include grunerite, hornblende, hedenbergite, ferrohypersthene (ferrosilite), and fayalite.

Jan 1, 2007

By Peter L. McSwiggen

The mineralogy of the Biwabik Iron Formation changes dramatically from west to east as the formation nears the basal contact of the Duluth Complex. This reflects a contact metamorphism that took place with the emplacement of the igneous Duluth Complex at temperatures as high as 1200 °C. However, the mineralogy of the Biwabik Iron Formation also varies vertically through the stratigraphy of the unit. This variability in both the vertical and horizontal dimensions makes it difficult to predict exact horizons where specific minerals will occur. The iron-formation has been subdivided into four broad stratigraphic units (lower cherty, lower slaty, upper cherty, and upper slaty) and into four lateral mineralogical zones (1-4). Zone 1, the westernmost zone, is characterized by quartz, magnetite, hematite, carbonates, talc, chamosite, greenalite, minnesotaite, and stilpnomelane. The silicate mineralogy in Zone 2 of the Biwabik Iron Formation changes very little. However, the minerals begin to change dramatically in Zone 3. Most significantly, Zone 3 is characterized by the appearance of grunerite in both a tabular form and a fibrous form. In Zone 4, the original silicate minerals have completely reacted, and a new suite of minerals occupies the iron-formation. These include grunerite, hornblende, hedenbergite, ferrohypersthene (ferrosilite), and fayalite. © 2007 Elsevier Inc. All rights reserved. Keywords: Biwabik Iron Formation; Duluth Complex; Mineralogy

Jan 1, 2007

By Scott G. Britton

Mine exploitation is a broad subject whose focus is the technical skills or efforts needed for the extraction of mineral from a known ore body. Mine exploitation can be considered the very core of the mining engineering discipline. It begins at the conclusion of the exploration and development stages of mining and ends when the ore body is exhausted and the mine (or mines)closes and is reclaimed. Section 8 on mine exploitation is comprised of seven chapters: (1) classification of mining methods, (2) mine surveying and mapping, 3) systems engineering, (4) computer methods, (5) labor relations and training, (6) management and administration, and (7) mine closure, sealing, and abandonment. Each chapter focuses its efforts towards providing detailed and useful information for the engineer on basic mine exploitation principles. The information can be applied to a broad range of mining problems without regard to mineral type or mining method.

Jan 1, 2008

By M. Kuchta, A. Newman

LKAB’s Kiruna Mine, located in northern Sweden, produces about 24 Mton of iron ore yearly using sublevel caving. For efficiency, the mine must deliver planned quantities of three ore products. We use mixed integer programming to schedule Kiruna’s operations, specifically, which production blocks should be mined, and when they should be mined to minimize deviations from planned production quantities while adhering to mining restrictions (e.g., sequencing). A new production block database and a well-formulated mixed integer programming model dramatically reduce the size of the original problem; in less than ten minutes we generate five-year schedules with time fidelity of months.

Jan 1, 2002

By Jayant Khambekar

In a typical mining operation, run-of-mine (ROM) ore is crushed and screened to achieve a desired particle size distribution and then fed to processing equipment for further refining. For an operation to be profit-able, the ore handling system from the mine face to final product loadout must be reliable. However, the handling system components do not always perform as expected and production problems related to material flow occur. These problems include flow stoppages, limited live storage capacities, uncontrollable flow, segregation, spillage and dust emissions. These result in lost production, excessive maintenance, safety and environmental issues, and even structural failures, in some cases. Flow patterns Flow problems and their solutions can be best understood by first learning how bulk solids flow. As bulk solids discharge by gravity from a storage system, primarily two types of flow patterns can develop: funnel flow and mass flow. Figure 1 shows a schematic of these two flow patterns. In funnel flow, only a portion of the material is in motion during discharge, which flows toward the outlet through a channel that forms within the stagnant material. Funnel flow occurs when a hopper is not sufficiently steep and smooth to ensure flow along the walls or when the outlet is not fully effective. In mass flow, all of the material is in motion whenever any is discharged ? there is no stagnant material. Mass flow occurs when the hopper is sufficiently steep and smooth to ensure flow along the hopper walls. Shallow valleys are not permitted and the outlet must be fully effective. A third type of flow pattern, called expanded flow, can develop when a mass flow hopper (or hoppers) is placed beneath a funnel flow hopper or bin. The mass flow hopper is designed to activate a sufficiently large flow channel in the funnel flow hopper to avoid flow problems due to a rathole. The flow pattern in which a bulk solid discharges from a storage system strongly influences the flow problems that may occur in that facility.

Jan 1, 2009

By Scott Ellenbecker

The formation in Newmont Mining?s Phoenix Mine near Battle Mountain, NV contains high levels of abrasive quartzite as well as gold, copper and silver. Newmont started mining operations at Phoenix (formerly Battle Mountain Gold) three years ago and the planners knew they were working with a challenging geological formation. But as it turned out, it was more challenging than anticipated. Mine manager Mark Evatz said, ?Anything that touches Phoenix rock wears fast. The rock fights back here.? To contend with the hard conditions, Newmont uses Atlas Copco?s Pit Viper 271 (PV-271) blasthole drill. Because of the hardness of the rock, drilling at Phoenix requires hammer drilling and the mine uses Atlas Copco TD65 hammers with 171 mm (6.75 in.) bits. The mine?s PV-271?s are outfitted with a single 41 m3/min (1450 cfm), 2.4 MPa (350 psi), oil-flooded air compressor. Phoenix has six Atlas Copco PV-271 drill rigs plus an Atlas Copco DML and a DM45 midrange blasthole rig. The mine?s goal is to keep 3.6 Mt (4 million st) of muck in inventory to stay ahead of the shovels and support needed operational flexibility (ore control related). Drilling efficiency has been a continuous point of improvement since operations began at the mine. The single-pass depth capability of 16.5 m (55 ft) on the PV-271 helped with that. Originally, the plans called for 6-m (20-ft) bench heights, supported by 7-m (23-ft) drill depths, and time spent moving from hole to hole was eating up productivity. Drilling on that plan resulted in drilling an average of 14 m/h (47 ft/hour). When depths were changed to 13-m (44-ft) drill depth, supporting blasting of 12-m (40-ft) benches, they were able to use the single pass capacity of the PV-271. Performance increased to more than 18 m/h (60-ft/hour) an hour. Although the drill depth change largely supported the improvement, other aspects of continuous improvement associated with improved knowledge of the Pit Viper drills helped as well.

Jan 1, 2009

By K. W. Lee, C. Pound, J. Carmody, L. Petersen, C. Nelson, J. G. Cai

The feasibility of developing the Underground Science City below the Kent Ridge Park has been investigated. The primary aim of the study has been to explore the possibility of creating underground space to house a new community of research laboratories and offices. The investigation represents the first such study undertaken in Singapore for a non-military underground facility. The paper describes the geology of the Underground Science City site and illustrates the layout and plan of the Underground Science City. The geology and rock mass below the Kent Ridge Park is generally favorable for the development of an underground cavern complex. Underground Science City can be potentially developed housed in a cavern complex. Several potential development schemes are studied; with various combination of deep/shallow mined caverns of different span sizes and access options. The preferred scheme is shallow, mined room-and-pillar caverns with large spans and shaft accesses at both existing surface Science Park 1 and Science Park 2. The scheme can be potentially expanded laterally to create more underground space for new Underground Science Cities at Kent Ridge area.

Jan 1, 2001

By James Withers, Dongbo An, Jinhong Zhang

A micro-scale investigation was carried out by applying atomic force microscopy (AFM) to study in situ the adsorption of various collectors, i.e., oleic acid, octanohydroxamic acid (HA), and salicylhydroxamic acid (SHA), on bastnaesite in aqueous solutions. The obtained AFM images show that the surface morphology of bastnaesite changes greatly after it comes into contact with the solutions of the collectors, suggesting that all these collectors can effectively adsorb onto bastnaesite. Increasing temperature can facilitate the adsorption of oleic acid onto bastnaesite. Results from attenuated total reflectance–Fourier transform infrared spectrometry (ATR-FTIR) also show that all of these collectors adsorb strongly onto bastnaesite, with strong absorbance spectra being detected. The ATR-FTIR results confirm those obtained by AFM. In general, hydroxamic acid collectors (HA and SHA) adsorb onto bastnaesite mainly in the form of insoluble metal hydroxamate. This specific adsorption mechanism explains that a high selectivity with a moderate collectivity will be achieved with a hydroxamic acid collector for the flotation of bastnaesite.

By James Withers, Dongbo An, Jinhong Zhang

A micro-scale investigation was carried out by applying atomic force microscopy (AFM) to study in situ the adsorption of various collectors, i.e., oleic acid, octanohydroxamic acid (HA), and salicylhydroxamic acid (SHA), on bastnaesite in aqueous solutions. The obtained AFM images show that the surface morphology of bastnaesite changes greatly after it comes into contact with the solutions of the collectors, suggesting that all these collectors can effectively adsorb onto bastnaesite. Increasing temperature can facilitate the adsorption of oleic acid onto bastnaesite. Results from attenuated total reflectance–Fourier transform infrared spectrometry (ATR-FTIR) also show that all of these collectors adsorb strongly onto bastnaesite, with strong absorbance spectra being detected. The ATR-FTIR results confirm those obtained by AFM. In general, hydroxamic acid collectors (HA and SHA) adsorb onto bastnaesite mainly in the form of insoluble metal hydroxamate. This specific adsorption mechanism explains that a high selectivity with a moderate collectivity will be achieved with a hydroxamic acid collector for the flotation of bastnaesite.