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By L. O. Filipov, N. E. Menad, A. Geneyton

"Zeta potential of synthetic monazites presenting various compositions were measured to investigate the effect of the main lanthanides substitutions on electrophoretic mobility and resulting IEP. The measurements are performed in a CO2 depleted and enriched solutions showing both reduced influence of monazite chemistry and strong influence of ions resulting from the solubilization and dissociation of CO2. The influence of oleic acid on the electrophoretic mobility of those monazites was also investigated. The influence of pH on oleate adsorption was studied using a bubble/particle adhesion system. Adhesion strength measurements were performed on pure synthetic monazite-(Ce) and monazite-(La). An extensive thermodynamic model of monazite in water was developed to highlight correlations between lanthanides hydroxides/carbonates species concentrations in the bulk solution and oleate adsorption. Based on electrophoretic measurements, advanced thermodynamic consideration and adhesion measurements, further details of the oleate adsorption model on monazite surface were proposed.INTRODUCTION Electrophoretic and potentiometric data on monazite and, a fortiori, other rare earth semi-soluble salts such as bastnaesite are extremely erratic (Chelgani et al. 2015). The isoelectric points measured with electrophoretic mobility methods range from 4.7 to 6.5 although sporadic data indicates an IEP (isoelectric point) far from that range. Different explanations are proposed in the literature to explain the IEP variability notably the numerous chemical substitutions that frequently occurred within monazite crystal lattice (Chelgani et al. 2015). Based on lanthanides speciation diagram, several authors highlighted the influence of specific lanthanide species on the flotation performance of rare earth semi-soluble salts when carboxylate or hydroxamate collectors are used. Although lanthanides ions have a great affinity for carbonates groups (Kragten et Decnop-Weever 1987), lanthanide (hydrogen) carbonates were not implemented in speciation diagrams. In this work, an advanced thermodynamic model is proposed to highlight correlation between flotation performance and lanthanide species predominance but also concentrations. Qualitative measurement of the monazite surface hydrophobicity are performed through tests of adhesion of coarse monazite particles onto bubbles. Since flotation and microflotation technics are highly influenced by hydrodynamic parameters, this method was investigated to obtain a sharp contrast between appropriate and inappropriate pH conditions. This paper is to investigate 1) the effect of lanthanides substitution on monazite surface properties through zeta potential measurements, 2) the mechanism of adsorption of carboxylates on monazite surfaces and 3) the effect of CO2 on monazite surface properties and carboxylates adsorption."

Jan 1, 2018

By D Symonds, S S. Kanchibotla, L Kennelly, G McNamara, J Gaunt, B Adiyansyah

Ban Houayxai is a gold-silver mine operated by Phu Bia Mining Limited in Laos since 2012. The first two years of operation processed predominately soft oxidised ore but subsequent years were expected to process more fresh hard ore. Fragmentation of the fresh primary ores was also expected to be much coarser than for the soft oxide ores. This coarser and harder ore is expected to significantly reduce mill throughput and mining productivity. The Ban Houayxai management realised the potential downside risk when processing fresh harder ores and implemented a blast optimisation project to deliver finer fresh ore to the mill without unduly increasing blast induced dilution and damage.JKTech and the Ban Houayxai drill and blast team began a joint blast optimisation project in April 2013 to achieve finer fragmentation from fresh ores. This was achieved by modifying the bench geometry, blast patterns and applying exceptionally high levels of quality control during implementation. Blast induced ore loss and dilution was controlled by adjusting the ore blocks for blast movement. Finer fragmentation from these modified designs improved mill throughput for the hard fresh ore by 46 per cent above design on average. These new practices have been embedded in site operating procedures and have provided a quick reference ‘cookbook’ document for the engineers.CITATION:Gaunt, J, Symonds, D, McNamara, G, Adiyansyah, B, Kennelly, L, Sellers, E J and Kanchibotla, S S, 2015. Optimisation of drill and blast for mill throughput improvement at Ban Houayxai Mine, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 307–314 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By John R. Troxell

"INTRODUCTION The Ahles iron mine, also known as the Pequest mine, in Warren County, N. J., was operated continuously for 15 years and was still in ore when it closed in 1916.Tie property was examined by an engineer of the Bureau of Mines in March 1943. 3/ This examination led to an investigation of the deposits by the Bureau by diamond drilling two holes under the old workings to determine whether the extends downward.This report describes the work done at the Ahles mine by the Bureau and presents the data obtained.ACKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. The Mining Division, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual investigative work, and prepares the final report.The Metallurgical Division, O. C. Ralston, chief, analyzes samples and performs beneficiation tests.The investigation was under the general supervision of J. B. Zadra, acting regional engineer, and under the immediate supervision of G. D. Jermain, district engineer for the States of Pennsylvania, New Jersey, Maryland, and Delaware. The author was in direct charge of the project.The chemical analyses for the project were performed at the College, Park, Md., laboratories of the Bureau of Mines under the direction of M. S. Sheftel. The ore-dressing tests were conducted at College Park under the direction of Frank Lamb. Preston E. Hotz, of the Federal Geological Survey, logged and interpreted the drill cores."

Apr 1, 1948

By Malti Goel

"The cost-effective capture of carbon dioxide (CO2) from the point sources for its reduction the atmosphere offers many challenges in materials science. Novel CO2 capturing approaches using chemical, physical and biological methods are in the research stage and are aimed to minimize the cost. Appropriate materials development , which can withstand required temperature or pressure as the case may be for CO2 emanating from coal gas or industrial waste gases form the minimum condition. Other requirements are reclyclability of material and cost of separation. Nano-material composites can be more effective in selective capture of CO2 and can offer solutions for large-scale separation process. Nano-porous material catalysis can enhance the reaction rate of CO2 with other chemicals and thus help in capture of CO2 and convert it into value added products. This paper reviews recent industrial scale developments. In the Indian context, R&D priority areas in CO2 capture process development with a focus on energy industry are presented.IntroductionScience of Climate Change is growing at an enormous pace. With the ultimate goal of stabilization of greenhouse gases in the atmosphere, new scientific approaches are being researched worldwide. A shift in policies from low carbon and no carbon energy sources to fossil fuel sources with capture of carbon and its permanent storage is taking place. The process of carbon capture is both energy and materials intensive and the cost of power generation may increase up to 40% when carbon capture and storage (CCS) technology is implemented. Development of cost effective R&D technology therefore remains the greatest challenge before the scientific community."

Jan 1, 2009

By A. C. Fieldner

Much activity is called for in the present period of hightened national effort, and wise direction of such a program must always be conditioned by positive knowledge gained in years of slow and painstaking study and development. Research and technologic investigations on coal by the Bureau of Mines have been described in a series of annual

Jan 1, 1941

By F. W. Horton

This paper covers the salient features of the occurrence and mining of sheet mica in the United States and the preparation of mica for market; presents the results of a study of the physical properties of domestic and foreign micas, which the author hopes may he of interest to every mica user, as it definitely answers many questions as to the suitability of various minas for particular purposes; and discusses mica-trade conditions and the future outlook for the domestic mica industry. ACKNOWLEDGMENTS The author takes pleasure in acknowledging his indebtedness to J. R. Thoenen, of the United Stator Bureau of Mines, under whose guidance the work reported herein was performed, and to Frank L. Hess, also of the Bureau, for information on the geological and mineralogical characteristics of mica-bearing pegmatites.

Jan 1, 1935

By O. H. Metzger

This is one of a series of capers being published by the Bureau of Mines on gold mining A the Western States. It describes the production of gold in the principal mining districts of New Mexico. The material was gathered red on a trip through tale State in the summer of 1936. ACKNOWLEDGMENTS The author acknowledges the aid and cooperation of mine operators in all parts of the State, who willingly contributed all information requested. Geological reports of the Geological Survey and the New. Mexico Bureau of Mince were drawn upon freely for information; credit to individual paper, is given in the text.

Jan 1, 1938

By Richard Lusignea

A single boom roof bolting machine was outfitted with measurement and recording systems for detecting changes in machine parameters while drilling. The purpose of this instrumented bolter or "smart drill" is to detect changes in roof conditions from the machine parameters of penetration rate, thrust, rotation rate, torque, rejected light from rock cuttings, and vibration of the roof during drilling. The system was demonstrated underground in coal mine conditions and showed correlation between rock type and drilling parameters.

Jan 1, 1982

By William J. Kemnitzer

This study was made to show the growth of petroleum coking and to determine trends and characteristics of marketing and utilization of coke on the West Coast, comparing these data with those of the United States as a whole. An earlier Bureau of Mines economic survey of petroleum coke was made in 1930 before the widespread use of coking processes. Data, derived from published and unpublished literature as well as from interviews with industry representatives, show a marked increase in the production of petroleum coke since the end of World War II. This increase resulted from the need of refiners to upgrade heavy residuums for which the demand was diminishing. Increasing coke production as well as significant market shifts away from California-produced coke have created excessive stocks of petroleum coke on the West Coast. The causes of these market shifts were based mainly on (1) economic factors and (2) certain undesirable qualities of some of the petroleum coke produced in California.

Jan 1, 1965

By A. C. Fieldner

This report is the fourth of a series of annual summaries of research and technologic work on coal by the Technologic Branch of the Bureau of Mines. The coal research program of the Bureau has been broadened and made more flexible to adapt it to changing conditions and needs of the coal industry, and as a result information as to the properties and composition of coal has been increased and new and improved practices in mining, preparation, and utilization of coal have been devised. The present

Jan 1, 1940

By William J. Kemnitzer

This study was made to show the growth of petroleum coking and to deter- mine trends and characteristics of marketing and utilization of coke on the West Coast, comparing these data with those of the United States as a whole. An earlier Bureau of Mines economic survey of petroleum coke was made in 1930 before the widespread use of coking processes. Data, derived from published and unpublished literature as well as from interviews with industry representatives, show a marked increase in the production of petroleum coke since the end of World War II. This increase resulted from the need of refiners to upgrade heavy residuums for which the demand was diminishing. Increasing coke production as well as significant market shifts away from California-produced coke have created excessive stocks of petroleum coke on the West Coast. The causes of these market shifts were based mainly on (1) economic factors and (2) certain undesirable qualities of some of the petroleum coke produced in California.

Jan 1, 1965

By Carl L. Bieniewski

In a Bureau of Mines supply evaluation, the known uranium resources in the United States are estimated to have a total recoverable uranium oxide (U3O8) content of 3,132,400 tons at prices up to $69.32 per pound. Only those resources were evaluated for which sufficient quantity data are available and process technology exists for recovering uranium. A total of 160,800 tons of U3O8 is available at $8 per pound from ore deposits presently mined and an additional 244,700 tons available at prices up to $30 per pound from similar but usually lower grade deposits. A total of 2,726,900 tons of U3O8 is available from four other resources: copper leach solutions, wet-process phosphoric acid, Florida phosphate rock Leached zone, and Chattanooga Shale. These resources contain from 30,000 tons of recoverable U30, at a price of $7.52 per pound as a byproduct of copper leach solutions to 2,557,300 tons at a price of $69.32 per pound from Chattanooga Shale.

Jan 1, 1971

By D. E. Redmon

The Federal Bureau of Mines has studied the locations and general features of 90 pegmatites found in north-central New Mexico. The dominant valuable product of the pegmatites is muscovite, both sheet and scrap. However, the Harding pegmatite in Taos County is mined only for beryl. Many attempts have been made to recover scrap mica on a large scale by mechanical beneficiation of pegmatite, but the operations heretofore have been short-lived. The Globe mine and the Apache mine, both near Petaca in Rio Arriba County, have been the most important sources of sheet mica in New Mexico. Recognition of the growing need for some of the minerals derived from pegmatites led the Bureau of Mines to investigate the occurrences of pegmatite.

Jan 1, 1961

By John G. Hall

Everyone forms his own mental picture when the subject of copper is mentioned. To an architect, copper is a warm, enduring metal with a quiet beauty; to the historian, man's first metal; to the product engineer, the best electrical and thermal conductor of all commercial metals; to the investor, a volatile stock; to the speculator, the daily price quotation; to those in the mining industry, the challenge of producing copper for rising needs in the face of rising costs and lower grades of ore. At this meeting, we will look upon copper as a key raw material in industry, in national defense, in technology, in world trade, and as a principal commodity in the economies of several developing countries. As miners, and most of us here are miners, we are prone to view our role as suppliers of copper. We locate, mine, smelt and refine the metal. In the complexities of today's world, however, following a period of the longest domestic copper strike in history which caused critical world-wide shortages and widely fluctuating prices; it becomes necessary for all of us to concern ourselves with the whole spectrum of copper affairs -"from mine to consumer " But first we need to look at the miner's side of the picture -- capacity and production. We will examine these functions in terms of the whole world -- not simply the free world. Nature did not endow all regions of the earth equally, and copper in world trade has a way of ignoring political boundaries. Science and technology, as well, know no national boundaries. It is said that the "Engineering & Mining Journal" has as many readers in the Communist World as in the Free World. Nor is this a one-way street. We presently have available to us in the. U.S., cover-to-cover translations of many Communist World mining and metallurgical journals.

Jan 1, 1968

By Orestis Zarzouras, Amalia Giannakou, Jacob Chacko

"When designing structures in seismically active areas, foundations of critical structures are typically located away from known faults. Indeed many seismic codes prohibit construction in the immediate vicinity of seismically active faults establishing minimum setbacks from the faults. However, for long structures such as bridges, tunnels and pipelines, a fault maybe unavoidable, and fault rupture risk impossible to preclude. This paper presents a case study of a bridge foundation design that incorporates the consequences of fault deformations passing through the foundation. A series of site surveys were conducted to characterize the fault environment, and fault displacement hazard analyses were conducted to develop design displacement demands. Subsequently, numerical analyses were performed to evaluate the fault rupture-induced demands on a pier foundation in terms of displacements and rotations. Initially, analyses were performed that model the free field fault rupture propagation to the ground surface of the fault to ensure that the basic site characteristics are captured. Subsequently, the foundation elements were introduced in the model and the fault rupture is simulated again. The interaction and influence of the foundation on the fault rupture propagation is calculated, and the consequent demands and distortions of the foundation block provide a basis for structural engineers to design the bridge.IntroductionThe Izmit Bay bridge, a 3-km-long suspension bridge that crosses Izmit Bay in Turkey, is planned to be constructed in one of the most seismically active places in the world. The south approach structures for the Izmit Bay Bridge along the western side of the Hersek peninsula bring the bridge down from on the order of El. 60 meters at the South Anchorage to an elevated embankment approximately 1.3 km farther south (Figure 1). The south approach structures are located within a zone of secondary deformation around the primary trace of the North Anatolian Fault. The concept design team has developed a concept design for a “viaduct” structure that consists of 10 spans with lengths varying between 136 m and 100 m and two back spans one of 125 m, attached to the main bridge and the other of 74 m attached to the south embankment."

Jan 1, 2017

By A. Klingberg, M. Svensson, N. Smolko Schwarzmayr

"Removal of silicates and carbonates from sedimentary phosphate ores by the use of new synthetic collector/formulations was investigated in a comparative study with traditionally used collector systems as references. In the direct carbonate flotation the new formulations showed higher efficiency, contributed to an improved balance of P2O5 recovery and P2O5 enrichment in the recovered material. Efficiency of the new formulations containing synthetic surfactants was 1.5–2 times better than potassium salt of fatty acid sulfonate based formulations that are traditionally used for that purpose. The new formulations also provided up to 7% increase in P2O5 recovery at the same P2O5 grade. The new synthetic collectors for removal of silicates showed extremely good selectivity towards silica bearing minerals. The selectivity factor for the flotation tests when new formulations were used was 32–52 and for the flotation tests with the traditional collectors: 20–32. The ratio between distribution of an amount of silicates (as SiO2) and distribution of phosphate in the froth (waste) is defined as the selectivity factor. The new formulations provided more than 2% decrease of the amount of SiO2 at the same P2O5 recovery.INTRODUCTIONPopulation growth and decrease of arable land are the main reasons for constant increase of consumption of apatite (phosphate ore) in the fertilization field (Lannefors, Gorochovceva, Klingberg, Lima, & Gustafsson, 2015). Fertilizers play a key role for farmers to produce more with less land. The phosphate component of the fertilizer is vital for producing healthy and large amount of crop. As a result the demand for phosphate rock is growing.The largest producers of phosphate rock are the Unites States, Morocco, Tunisia, China, Russia, and Brazil. The term “phosphate ore” includes all phosphate-bearing minerals and rocks, but only two of them are of industrial interest: apatite (igneous origin) and sedimentary phosphate (Peres, Araujo, El-Shall, Zhang, & Abdel-Khalek, 2007). The majority of the world’s phosphate deposits are of the sedimentary type. There are two different types of sedimentary phosphates: siliceous and carbonaceous which are categorized based on gangue minerals (such as quartz, carbonates, mica, and clay)."

Jan 1, 2016

By G. C. Amstutz

The topic of the industrial applications of mineralogy is a vast field which can be adequately covered only in a large book or by a two or three semester course. This paper recalls experiences of the writer in this field, a task requested by the Process Mineralogy Committee. Therefore, this paper is largely an account of the industrial mineralogy problems I was involved with, since my student years, Although I will treat each application only briefly, it is hoped that they will illustrate to the students in the field how varied are the applications of mineralogical methods. In this respect, I want to emphasize that it is important for mineralogy teachers to point out the usefulness of mineralogical methods much more often in their courses. Not only does that help prepare young individuals for industrial careers, but also it arouses their feeling of consciousness of public responsibility which is an important attribute for the world's scientists. When professors utilize the varied applications in their teaching of mineralogical methods students then understand better the significance of learning those methods and appreciate the many years of necessary university preparation. The first time I was involved in an application of mineralogical methods was about 1944 as a student of Professor Paul Niggli. He was asked to study the problems of ice crystallization on wings of airplanes. The ice formed at high altitudes and during the winter. This was not outside his realm of expertise because he was the main initiator of the Snow Research Institute on the Weissfluhjoch in Switzerland. I believe that the work of this Institute was an important factor in stimulating much of the snow research subsequently carried out at the United States Army Snow Research Center, which was located at that time in Willmette near Chicago. Dr. Bader, one of Paul Niggli's former students, was the Director of Research at Wilmette at that time and for quite a number of years thereafter. A mineralogist-crystallographer can make important contributions to a better understanding of the problems of snow and ice formation, avalanche hazards, and the prevention of hail. The habits of snow crystals are essentially a function of the temperature and the humidity,

Jan 1, 1982

By F. Chen, L. J. Gaydos, D. C. Kuhn, Demersm L. M., S. C. Sun

"Summary: In this report the differential regulation of NF-KB and nitric oxide (NO) was investigated in the mouse macrophage cell line RAW 264.7 following exposure to a mineral dust (silica) and /or an endotoxin (Lipopolysaccharide, LPS). The results indicated that silica and LPS can significantly induce the activation of NF-KB as well as elicit enhanced production of NO in RAW 264.7 cells as part of an early inflammatory response mechanism. A 24-hour time-course study showed that NO release from these cells continued to increase following the initial stimulus by LPS or silica. In contrast, activation of NF-KB was maximal at 6 hours and then showed a steady decline to 24 hours. The production of NO was suppressed by protease inhibitor and antioxidant, both of which block the activation of NF-KB. Surprisingly, the use of an NO synthase inhibitor resulted in an enhancement of NF-JCB activation. These findings suggest that NO produced in macrophage cells in response to an inflammatory stimulus like silica or LPS my be linked to a negative feedback role on the activation of NF-KB. It is now accepted that nitric oxide (NO) plays a pivotal role in the inflammation response process when macrophage cells are activated by a pro-inflammatory stimulus (l). Production of NO is dependent on the activity of the enzyme nitric oxide synthase (NOS). Up until now, at least three distinct genes have been described which encode different isoforms of NOS. NOS has been cloned from a variety of different mammalian cells, including constitutive neuron NOS, constitutive endothelium NOS and inducible NOS (2). Macrophages appear to be the principal cellular source for the inducible form of NOS (iNOS) activated in response to an inflammatory producing event. The mechanisms subserving the regulation of the iNOS gene and NO production have been under intense investigation in recent years (3-5). Several binding sites for transcriptional factors have been identified in the promoter region of iNOS gene, including NF-lCB, AP-1, NF-IL6, Oct-I to cite a few (5). NF-KB appears to play a"

Dec 1, 1996

By S. Z. R. Pinkney

Positron Emission Tomography (PET) is a medical technique that produces three dimensional images of the body, commonly to aid diagnosis and treatment of tumours. PET has been developed by the University of Birmingham in order to track particles in an opaque system which is known as Positron Emission Particle Tracking (PEPT). The object to be tracked is irradiated. As the radionuclide decays positrons are produced; when these collide with electrons a pair of concurrent parallel back-to-back gamma waves are emitted and detected, from which the position of the object can be calculated. Stirred media mills are used for particle size reduction. The mill is usually operated at high solids loading with grinding media and has a polyurethane or polyurethane-lined steel pot and is thus opaque. For this study grinding media has been directly irradiated and tracked using the PET camera during the grind. The stirred media mill can be divided into cells of equal volume known as voxels. The fraction of the total time the irradiated media spend in each voxel can be shown in an occupancy diagram. The mean velocity and kinetic energy of the media for each voxel are calculated and also plotted. In occupancy and kinetic energy plots colour indicates the value of the voxel, in dimensionless time and Joules respectively. The arrow in velocity plots shows direction and length of arrow indicates magnitude of the mean velocity for the voxel. From these diagrams and further data analysis a detailed understanding of the flow patterns, media behaviour and high energy areas of the mill can be developed. Variables considered were the tip speed of the impeller and density of the grinding media. It was found that the grinder has three distinct regions: above, at and below the impeller with each region having its own flow patterns and velocity and kinetic energy profiles. These are different for each variable and so are used to characterise the grind. Tip speed and density of the grinding media were shown to both affect the velocity of the media and the proportion of time spent in the each region of the grinder.

Aug 1, 2013

By P A. Kirsch, A Hine

Mining is a major global industry that requires the moving of considerable volumes of earth and rock (overburden) to win the valuable ore prior to mineral extraction and processing. As a result of this process, new landscapes are created, both extracted voids and overburden piles, as well as infrastructure for management of mine operations, wastewater, tailings, other raw materials, transportation and extreme rainfall events. Resource companies must develop and obtain regulatory approval for detailed plans that manage this displaced material through all phases of the life-of-mine and rehabilitate the site at the time of closure (including landform stability, revegetation and ongoing management).Individual mine sites operate in long time frames (ten to 50 years), with several mines often operating in the same region, generating cumulative overburden volumes and heavily altering the original landscape. These impacts are universally framed as a negative consequence of the industry, especially by modern society that values natural (and some agricultural) landscapes as pristine and almost sacred. Overburden and tailings are also seen as a problem, and are a significant business cost to mining practice.This paper looks to investigate perceptions of mining and post-mining landscapes, questioning the aesthetically driven emphasis on the ‘natural’. It proposes instead an opportunity to reframe the way we look at overburden and landscape impacts from mining, exploring the possibility of imagined post-mine landscapes unburdened by traditional aesthetic expectations. These landscapes, to be conceived by regional stakeholder roundtables, have the capacity to be built by regional mining consortia as a foundation for sustainable post-mining economies.Post-mine regeneration offers both the motivation and the basic materials to create an altogether new environment from a blank slate. Few circumstances allow the opportunity to truly explore a re-envisioning of the land on a huge scale, and the possibilities merit serious consideration.CITATION:Hine, A?and Kirsch, P?A, 2014. Dreams of futures past – curating post-mining landscapes, in Proceedings Life-of-Mine 2014 , pp 121–138 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014