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By Irene Bendanillo, Canon Cheung, Justin Lianides, Derek Penrice

The SLAC National Accelerator Laboratory’s two-mile-long particle accelerator generates the world’s brightest X-rays from its Linac Coherent Light Source (LCLS) freeelectron laser. This facility has driven groundbreaking discoveries in medicine and industry. The LCLS-II-HE project will provide a significant increase in laser energy, allowing cutting-edge research in fields including biology and environmental science. A key project component is the Low Emittance Injector Tunnel (LEIT), a 240-foot-long tunnel to be built alongside the existing accelerator and connected to it via a 30-footlong Transfer Tunnel. This paper discusses site and scientific constraints that led to the selection of the LEIT configuration: tunnels to be constructed using the sequential excavation method in mixed-face conditions comprising native rock and placed backfill, and critical design considerations including protection of overlying and adjacent historic structures and structural accommodation of near-fault seismic loading.

Jun 13, 2023

By David Atkin

This paper presents methods and results of environmental planning conducted for a proposed coal and iron ore transshipment terminal which would be located on reclaimed land west of Lisbon, Portugal. Oceanographic, navigational, marine, structural, material handling, and financial studies of the terminal were conducted along with the environmental analyses. However, because of the proximity of the terminal to heavily used recreational resources, residential areas, and biologically valuable habitat, anticipating and reducing the environmental effects of the terminal to minimum levels was a very important part of the overall project. The results of the study indicate that even the impacts associated with worst-case conditions would be acceptable because of appropriate pollution control measures and planning.

Jan 1, 1983

By Young C. Kim

Use of geostatistics to solve mining problems is gaining importance as the cost of developing new mines is increasing and there is a need to mine more marginal deposits. But, until recently, coal companies have shown little or no interest in geostatistics. However, the stringent quality controls on coal burning has led to a surge in interest in improved methods for estimating clean coal characteristics. Until now, most of the geostatistical applications have centered on the problems of estimating in-situ coal characteristics (Sabourin, 1975; Wood, 1976, 1979; Fang and Stark, 1976; Pauncz and Nixon, 1979; and Knudsen et al., 1980). Little work has been done in applying geostatistics to coal washability, except that by Armstrong (1980). Applying geostatistics to coal washability basically means the estimation of cleaned coal characteristics, with the aid of geostatistics. Cleaned coal estimation plays a very important role in overall emission control strategy, as can be seen by the general flow diagram of such a strategy shown in Figure 1. The scope of this paper is limited to one aspect of the overall emission control strategy shown in Figure 1; namely, the prediction of cleaned coal characteristics using geostatistics.

Jan 1, 1982

By Robert J. Henning

The term olivine was first used in 1790 by J. Werner, and the corresponding mineral was so named because of its olive-green color (Hunter, 1941). Olivine is the principal component of the rock known as dunite. While by classic definition dunite is composed of 90% or more olivine, commercial use of these terms has resulted in more specific definitions. Commercially, the term olivine is used to designate a material that consists of 85% or more forsterite and contains 45 to 50% MgO, 39 to 42% SiO2, 5 to 8% Fe2O3, and has an ignition loss (LOI) of 1 to 2%. The term dunite designates a rock that contains 36 to 45% MgO, 36 to 39% SiO2, and has an ignition loss of as much as 10% (Teague, 1983). GEOLOGY Olivine is found in basic igneous and basic metamorphic rocks whose age varies from pre-Ordovician to Tertiary. Economic deposits are of magmatic origin and are restricted to the dunite variety of the peridotite group of ultrabasic igneous rocks. Olivine also occurs in basic igneous rocks such as gabbro, basalt, and diabase and more rarely as an accessory mineral in granite and metamorphosed crystalline limestones. Mineralogy The term olivine refers to a group of orthosilicate minerals in isomorphous series with magnesium-rich forsterite (Mg2Si04) as one end member and iron-rich fayalite (Fe,SiO,) as the other. In most olivines the ratio of magnesium to iron varies from 16: 1 to 2: 1. Commercial olivine deposits contain a mixture of forsterite and fayalite with the fayalite content restricted to less than 15% (Reed, 1959; Teague, 1983). Accessory constituents may include primary minerals such as ilmenite, magnetite, diopside, chromite, and garnet and secondary minerals such as chlorite, serpentine, talc, and vermiculite as alteration products. Chemical and Physical Properties The chemical composition of olivine can be expressed as either (Mg, Fe), SiO, or 2(Mg, Fe)O.SiO,. Table 1 presents chemical analyses for some commercial olivines. The physical properties of olivine are shown in Table 2. Distribution of Major Deposits Commercial olivine and dunite deposits are found in Norway, Japan, Spain, India, Italy, the United States, Sweden, Austria, Pakistan, and Mexico. Noncommercial deposits have been reported in New Zealand, Zimbabwe, South Africa, New Caledonia, Greece, Brazil, and Canada (Teague, 1983). The present markets for olivine are characterized by low unit value, high volume, and high sensitivity to freight costs, so few deposits are commercially viable. Literature from the USSR indicates that considerable research on olivine refractories is being done. (Afansa'ev, 1988), lending credibility to the conjecture that commercial deposits are being mined there. In eastern Canada synthetic olivine is being produced by calcining chrysotile asbestos mine tailings. In the United States numerous lenses of olivine extend in a belt from northeast Georgia northeastward across western North Carolina. Total reserves in North Carolina and Georgia are estimated at between 125 and 200 Mt. The largest US deposit is Twin Sisters Mountain, located in Whatcom and Skagit Counties in the state of Washington. This deposit, which has an outcrop area of 93 km2 and a relief of about 1 525 m. is estimated to contain 1 800 Mt of fresh, unaltered olivine (Teague, 1983). In addition, the US Bureau of Mines reports reserves of 50 Mt on Cypress Island in the state of Washington, and the literature reports eight complexes in southeastern Alaska, some containing cores of olivine as large as 1.6 km in diameter (Taylor, Jr., 1967). The world's largest deposit of olivine occurs in the Aaheim area of Norway, where reserves are estimated at a 2 000 Mt. Several other Norwegian deposits contain as much as 5 Mt each. In Japan the production of ultrabasic rocks is currently about 6 Mtpy, but the bulk of this output is serpentinite. Olivineldunite accounts for only 17% of this production. The major olivine deposit in Japan is located at Horoman Hill on the northern island of Hokkaido. Reserves at this deposit are estimated at 100 Mt (Anon., 1990). Spain is one of the largest producers of dunite. Reserves in the La Coruna District in northwestern Spain are estimated at 100 Mt. India, also a major dunite producer, has a large deposit at Salem in Tamil Nadu. In Italy olivine/dunite is mined from a deposit near Turin. In Sweden the largest deposit is at Arutats and is reported to be comparable in size to the Twin Sisters deposit in the United States. At present the only production in Sweden is from a deposit 30 km south of the town of Gallivare. Reserves at this deposit are reported to be between 1 and 2 Mt. Other significant deposits are: 1) in Austria at St. Stefan near Leoben, 2) in the Swat District of the North West Frontier Province in Pakistan, and 3) in Mexico at Cuidad Victoria in Tamaulipas (Anon., 1990).

Jan 1, 1994

By John Relser

The production processes that are developed in the mining and minerals industry are manufactured to be exposed to very aggressive environments. Chemical, abrasion, and impact expose structures and equipment, steel or concrete, to a significant deterioration. This causes damage and adds high costs to operations that can be reflected in the destruction of equipment and structures in the arrest of the production process, which becomes very costly. Also, there is the potential for personnel accidents, which would require large sums of compensation for an employee, thus directly harming the image of the mining operation and company. Manufacturers of paints and coatings that have major centers for research and development (R&D Labs) distributed globally have developed high-tech products for durable protection from the elements for structures and equipment used in the mining industry. The difference between these paintings and coatings and what is normally known as conventional paints (e.g., those called domestic or decorative), is its chemical composition, structured around polymeric components that have highly resistant, chemical and physical properties to cope with extreme conditions to which they are exposed. With this, and only this, longer life of components can be achieved for equipment and structures used in the production processes of the mining industry. Today, in addition to the important features mentioned, some manufacturers of the paints and coatings dedicated to this highly modernized process have invested large sums of money in developing new products that add operational elements to the painting process. These coatings provide added value and significant performance to companies mining operations and that we can describe in three fundamental concepts:

Feb 1, 2014

By David X. Zhang

This paper describes the results of using shear flocculation and flotation known as aggregative flotation technique for the enrichment of coal-derived char produced from mild gasification process. Aggregative flotation is a separation process which involves the use of suitable aggregating liquid under the action of high shear forces to render hydrophobic surface of coal-derived char particles to aggregate in an aqueous slurry. The fine carbonaceous particles are aggregated into larger floes while the impurities remain hydrophilic. In subsequent flotation process, the char aggregates are then separated from mineral matters by aeration in the flotation cell. The floatability of char aggregates and removal of mineral matters from chars are studied in a lab scale flotation column cell. The effect of various operating parameters on the aggregative flotation responses is presented. Emulsification of aggregating liquid using high intensity agitation and ultrasonic energy provides excellent aggregating liquid dispersion and increases selectivity for char aggregation. In subsequent flotation process, it results in significantly increasing the flotation rate of char aggregates. The microscopic examinations of bubble attachment to coal-derived char particles under various aggregating liquid dispersion levels were conducted by induction time measurement. The distributions of hydrophobicity of char particles and char aggregates prepared under various aggregating liquid dispersion techniques were measured by film flotation. The char particles prepared under high intensity emulsification attach at significantly faster rates to air bubble and with lower mean critical wetting surface tension than that of char with direct aggregating liquid addition. An interrelationship of increasing in flotation rate/combustible recovery with decreasing in induction time, mean critical wetting surface tension and dispersion of hydrophobicity on the char particles and char aggregates were obtained.

Jan 1, 1992

By T. S. Golosinski

This paper identifies the components of belt conveyor shifting force as a vertical force. Pv, horizontal force, Ph, and longitudinal force, P1. A method for estimation of these forces is proposed, which relates their value to the properties of the conveyor structure and rails, shifting operation parameters, and other site-specific conditions. The effect of this force on shifter behaviour is analysed and guidelines are developed for selection of a suitable shifter. Also discussed are the requirements of the shifting operation for other equipment.

Jan 1, 1986

By G. Heinrichs

This paper is intended to provide information for one to be able to determine the slurry system head curve for pump applications. The slurry characteristics are the basis for what the size, material of construction, and critical carrying velocity of the pipe will be. The system head curve is adjusted by use of the pipe friction coefficient factor and slurry derate factors. An example using multi-staging of slurry pump curves is presented to compare the wear life relationship of pump parts for a tailing pipeline system head curve.

Jan 1, 1996

By Nathaniel White, Todd Kilduff, Justin Laviolette, Dan Laviolette, Randy Zeigler, Sean Sundermann

The Mitchell Point tunnel is a part of several ongoing efforts to connect the 12-mile-long Historic Columbia River trail between Mitchell Point Outlook to Mitchell Point Drive. The tunnel lies inside the Mitchell Spur entablature basalt geologic feature, extending 647 linear feet utilizing a typical horseshoe section with a height of 14.5 feet. The Oregon Department of Transportation (ODOT) required proper vibration control to minimize potential impacts to Interstate 84 and Union Pacific rail immediately below the tunnel excavations and sensitive, rare plants. The method of designing the vibration monitoring program and the results of its implementation show the iterative process of using monitoring to improve blast design as excavation proceeds, such as reducing air overpressure and COVID-related supply chain-constraints.

Dec 1, 2022

By V. Voller

A relatively simple model of grinding which incorporates both the Bond grindability equations and the population balance equations has been extended to form a comprehensive simulation package that can describe most kinds of conventional grinding circuits. The package has two programs, with the first consisting of an input program which helps the user to specify the prescribed circuit, while the second program performs the actual simulation. The package serves two main purposes - i) as a check on mill design, with the output providing not only predictions for the product passing size but also of the full product size distribution, and ii) as a means to assess the likely effects on the product size distribution of operating under different sets of conditions.

Jan 1, 1981

By L. Diestelow

Evaporation and crystallization processes are used extensively in the mining industry to provide many pro-ducts. In the case of solution mining evaporators are used to concentrate, or to concentrate and crystallize the raw materials being mined. In the case of underground, or strip mining dissolving and crystallization are used in many processes in order to purify the ore to saleable materials. Presently evaporators and crystallizers are being used in the production of sodium chloride, potassium chloride, sodium carbonate, sodium sulfate, lithium chemicals, aluminum, and many others. The evaporator is a device designed to remove water or solvent from a solution. In an evaporator the energy released by steam condensing on one side of the heat transfer surface is transferred to the product solution on the other side of the heat transfer surface. As long as the boiling temperature of the product liquor is below the condensing temperature of the steam, the product solution will absorb heat. This heat absorption causes vaporization of the water (solvent) in the product solution resulting in concentration of the product. The simplest evaporator is the single effect evaporator. If we assume the feed introduced into the single effect evaporator is at its boiling point, ignore radiation losses, and assume the steam into the heat exchanger is dry and saturated, then the heat transferred will correspond to the latent heat of vaporization. Therefore, one kilogram of condensing steam will produce one kilogram of evaporation. Economies in energy usage compared to the single effect evaporator can be made by using multiple effect evaporators, or vapor recompression evaporators.

Jan 1, 1993

By Marline J. Veesaert

Urban quarries offer one of the greatest opportunities for profit in non-metallic mining with limited financial risk IF properly evaluated, planned and developed to meet market needs. Location, with respect to market, is the prime consideration. Geologic considerations and quality of rock are nearly as important. Cost factors and return on investment (ROI) are the principal financial considerations. Risk of capital is determined by weighing all factors that should be considered and how well judgements are based on information acquired. It is a simple, true axiom of business that an investment must be founded on amount of capital required with its expected return plus profit, expertise required to operate and time involved. Urban quarries generally offer excellent stone product market opportunities. Costs of land with mineral containment and processing operations are much greater than in rural areas. Environmental problems have become increasingly severe. Competition from other quarries in the market area is usually directly proportional to the profit attractiveness. Risk of capital (initial, developmental and operational) can be evaluated and reduced only by thorough analysis of the entire situation. Time and money expended on planning and preliminary investigations probably represent the most productive investment of available company resources.

Jan 1, 1977

By J. D. Miller

The fossil resins of certain western coals are of significance and of sufficient value as a chemical commodity to justify a fossil resin industry. At the present time these valuable fossil resin resources, worth more than $0.50/lb as a chemical commodity, are being burned as fuel for electric power generation. This waste of our fossil resin resources corresponds to a loss in revenue of $200 million per year -equivalent to the value of the coal itself! Improved process technology for the recovery of fossil resin is under development and includes selective flotation of fossil resin from fine coal streams and solvent refining of the fossil resin flotation concentrate to produce a premium resin product. The most recent developments in process technologies are discussed with respect to separation efficiency and product quality. It is clear that the development of a fossil resin industry should not be limited by process technology.

Jan 1, 1994

By James S. Falcone

Soluble sodium silicate materials have well known applications in flotation for desliming, selective depression and corrosion control. Recent advances in the understanding of the complex polymeric nature of silicate solutions using NMR spectroscopy, combined with our studies of the effects of polymeric silicate anions on metal ion activities in solution, oxide mineral surface charges and surfactant adsorption on clays are related to beneficiation processes. The results of these studies indicate the sodium silicates can be used to cause a solution chemistry and particle surface charge characteristics favorable to enhanced effectiveness in typical ore beneficiation systems.

Jan 1, 1981

By D. R. Nagaraj

Based on our finding that commercial copper chelating solvent extractants such as LIX65N® and LIX63® are excellent collectors for copper minerals, a detailed study was made using several water-soluble chelating agents belonging to the class of aromatic hydroxyoximes and having a gradual structural variation. A basic study of the system salicylaldoxime-tenorite was also carried out. Microflotation tests as a function of concentration of oxime, pH, addition of copper etc., using oxidic copper minerals such as chrysocolla and tenorite, and batch laboratory flotation tests using synthetic mixtures of quartz and oxidic copper minerals were carried out. The studies were aimed at an understanding of the collector function of the hydroxyoximes and of the general flotation behavior in these systems, in addition to studying the structural aspects of oximes vis-a-vis flotation. The results have demonstrated that all of the hydroxyoximes studied here have comparable collector property, and in all cases the oxime was found to be partitioned between the mineral surface and the copper in the bulk aqueous phase in the form of a bulk copper chelate. The occurrence of the latter could be accounted for by the formation in the bulk phase of a chelate between oxime and copper released from the mineral and/or by the detachment of the surface chelate. The role of surface and bulk chelates in flotation is discussed based on the results of partitioning of chelating agent into bulk and surface chelates in the system salicylaldoximetenorite. The effect of substitution of CH2 groups or benzene ring in the chelating agent molecule on its collector property is also discussed, in addition to the finding that only the anti-isomer has the ability to collect.

Jan 1, 1979

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 Miles L. Silberman

Three major suites of igneous rocks were erupted in the Great Basin in middle and late Cenozoic time. The first, most likely, resulted from sub- duction of a Pacific plate (Farallon plate) beneath the North American plate, resulting in eruption of andesitic rocks in the northern Great Basin between 42 and 43 m.y. ago. Between 34 and 17 m.y. ago, igneous activity migrated to the southwest, largely as eruption of volumincus rhyolite-quartz latite ash-flow sheets, ending about 17 a.y. ago with the onset of crustal extension and north-south-trending Basin and Range (rift) faulting. The second volcanic suite erupted between 17 and 8 m.y. ago in the northern Great Basin; is mostly basaltic or bimodal basalt-rhyolite. The third volcanic suite consists of andesitic and rhyolitic lavas and some basalt erupted between about 22 to 6 m.y. ago in the western Great Basin along the northwest-trending Walker Lane fault zone. Hydrothermal ore deposits are associated with all suites of igneous rocks, but the largest production has come from mines associated with andesitic rocks of the third (western Great Basin) suite. The oldest (34 to 42 m.y.) andesitic rocks (first suite) of the northern Great Basin have produced some large deposits; slightly younger silicic rocks of this suite are mostly barren. Many small ore deposits are associated with the 17- to 8-m.y.-old basalts (second suite) of northern Nevada.

Jan 1, 1976

By Klaus Grebe

Recent investigations by Mannesmann Research have shown that disintegration of sinter with widely varying quality levels is subject to a much more complex set of influences than was previously assumed. It was confirmed that disintegration at temperatures between 300 and 600 °C is triggered by the degradation of hematite. The specific tendency of hematite to disintegrate is, however, not constant: sinters containing the same amount of hematite can show widely differing disintegration tendencies depending upon structural homogeneity, porosity and gangue quantity. Especially sinters with heterogeneous structures transmit stress to the hematite phase and this favours disintegration. Another factor is the brittleness of the glassy silicate phase, which can be influenced even by small modifications of minor gangue constituents.

Jan 1, 1981

The 86th Annual Meeting of the SME Minnesota section/74th Annual University of Minnesota Mining Symposium partnered with the Canadian Institute of Mining Metallurgy and Petroleum (CIM)?s Iron Ore Symposium for a historic joint conference, held this year in Duluth, MN, April 15- 17. One of a flurry of recent collaborations between SME and CIM, the joint conference was a natural fit for the conference held in the heart of the Iron Range. As CIM National President Terence Bowles said in his joint keynote with SME President Jessica Kogel, ?The U.S. imports $51 billion from Canada and Canada imports $38 billion the U.S.; that?s 50 percent of Canada?s exports and 51 percent of its imports.? The two countries? economies are linked, and nowhere more closely than in their iron ore mining activities. Kogel opened the conference with a plenary speech identifying the top 10 issues facing mining and how these issues present opportunities for mining companies. She said that it is important that the mining industry stay flexible and adapt to changing conditions, or it will go the way of the dinosaur. However, she said that these challenges can lead to new opportunities. For example, one of the major challenges facing mining is the current state of risk aversion among investors, which makes for ?less money in the pipeline.? However, this situation creates a better climate for mergers and acquisitions, which is another, less risky way to get funding. Likewise, another challenge globally is geopolitical risk; this challenge is likely to drive growth toward stable countries, which was good news for an audience composed mostly of Minnesota and Canadian mining industry personnel. One of the highlights of Kogel?s address was a triangle illustrating the interdependent nature of sustainable development and corporate social responsibility (Fig. 1). This triangle consists of four equal components: the social environment, transparency, local and global impact and future generations. The most important takeaway, Kogel said, was that sustainable development and environmental and social responsibility, while they do add to the cost of doing business, are no longer optional.

Aug 1, 2013

By H. Shafick Hanna

The beneficiation characteristics of low grade Birmingham red iron ores of the Big Seam and Ferruginous Sandstone seams were investigated using flotation and magnetic separation after reduction roasting. Samples of Bib Seam Ore responded more readily to concentration than the Ferruginous Sandstone ores. The impurities inherent with the iron oxide minerals limit the grade of concentrates recoverable from these ores to a maximum of about 61% Fe if reasonable iron recoveries are sought. Flotation concentrates assaying 60-61% Fe and about 0.1% P with attendant iron recoveries of about 63% were achieved from Big Seam ore charges while those obtained from the low phosphorus Ferruginous Sandstone samples analyzed 54-56% Fe. Reductive roasting and magnetic separation of ground charges of the two ore samples yielded concentrates assaying 60-61% Fe. Iron recoveries were better than those achieved by flotation, but the magnetic products of Big Seam ore were high in phosphorus (0.2-0.3% P).

Jan 1, 1983