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By R. L. Miller

Two samples of iron enriched basalt (IEB) containing simulated nuclear fuel and having two distinct microstructures were prepared and tested for uranium recovery. The IEBs are refractory towards leaching by ground water. However, the uranium content (15.8%) is high enough that if aggressive leaching techniques are used for uranium recovery, these materials could be considered as man-made uranium ores. The IEBs discussed in this report were prepared to simulate Three Mile Island-2 core debris. The crushed IEBs were treated using three different methods simulating potential industrial scale processes. In one method the IEBs were fused with sodium hydroxide then the cooled mass leached first with water then with dilute sulfuric acid; about 52% of the uranium was recovered in this case. In the second method the IEBs were treated with a sulfuric acid/hydrogen peroxide lixiviant and about 13% of the uranium was recovered. In the third technique the IEBs were leached with a sodium carbonate/sodium bicarbonate/hydrogen peroxide solution. Only about 0.1% of the uranium was recovered. The results of these screening tests suggest that the IEBs can be successfully treated for recovery of the contained uranium. Other studies would be required to determine if other values, such as zirconium or silver, could be recovered from the IEBs.

Jan 1, 1984

By D Brown, K Markovic

The world is becoming an increasingly complex environment to operate within. Adoption and evolution of technology is occurring at a rapid pace and operating spaces are growing in interconnectedness and interdependency. In mining this is evidenced by the large-scale adoption of autonomous machinery, intelligent systems, Internet of Things (IoT) devices, and robotics to realise benefits in optimisation, productivity, and safety. To enable continual delivery and growth in operational performance, and to realise the aforementioned benefits, a new approach for managing mining and metals is required (Mining Review Africa, 2023). This means that an already talent constrained workforce must learn to manage the complexity inherent, evolving, and growing in the environment (Abenov et al, 2023). A key skill that needs to be further developed and deployed to combat these challenges and to enable robust problem solving is that of systems thinking, which is already practiced in pockets within the mining industry. Experience and learning can be leveraged from other industries and their application of systems thinking to ensure that focus is maintained on areas where the benefits from which will be optimised. With targeted application, a workforce capable of effective systems thinking can be the catalyst to optimisation across mining organisations.

Sep 1, 2024

"WELFARE…Welfare endeavor in connection with both the metal and the coal mines of Utah has shown gratifying progress during recent years and both the operators and their employees are deserving of much credit for the efforts put forth to better living, working, educational and receational conditions in most of the mining camps of the state.In the older metal mining camps of Utah, where the towns are incorporated and independent of the mining properties operating in the vicinity, less opportunity is pre¬sented for the companies to exercise efforts looking towards improved welfare conditions than is the case of camps located on company ground and under the full control of operators.Even in such camps, however, as illustrated in Bingham, the companies can do much to better welfare conditions. In this camp the Utah Copper Company has spent $800,000 since 1 920 in the erection of modern brick cottages, apartment houses and the Gemmell Memorial Club. The cottages and apartments have every convenience to be found in up-to-date city homes. The Gemmell Memorial Club, erected and equipped at a cost of $1 75,000, was provided by the company for the benefit of the Utah Copper Company employees living in the canyon and has been made the recreational center for the camp."

Jan 1, 1925

By Arthur Notman

THE raw material men in all industries, and copper is no exception, are accustomed to think of them- selves as the whole show, and not without justice, for if there were no copper mines the world would have no copper. Nevertheless, many different things costing money and resulting in profits must be done to their product before it is ready for the world's use. In other words, they are making the frequent mistake of Chinking in terms of partial costs. Nobody really uses electrolytic copper. Possibly that is why nobody seems willing to pay anything for it. The manufacturers, being canny, do not buy any more electrolytic than they feel that they can work up and sell profitably, although they like to make the raw material men Chink that they will take all that can be produced. This is a state of affairs that has aroused my sympathy and curiosity, and has induced me to study the financial history of the copper wire and brass industry of the country or such portion of it as publishes any records readily available to the curious minded. About 60 per cent of the electrolytic copper used in this country is drawn into wire and consumed by the electrical industries. The remaining 40 per cent is

Jan 1, 1926

By Omar. M. Arafat, Edgar Pérez, Kyle. M. Bartholomew, Robert. E. McIvor

The “circulating load” confounds understanding of ball milling circuits. Conflicting opinions exist as to its role. Should it be high, or low? Why does it even exist? It is commonly accepted in the plant as a given, the outcome of largely unknown factors. As such, it may often go unmeasured or even ignored. This paper describes the importance of the circulating load in wet ball milling circuits. It is characterized not only in terms of solids mass flow (or ratio of mass flows), but also by its other key physical characteristic, its size distribution. Its effect on grinding circuit performance is explained. The equipment application design steps to achieve a desired circulating load, in terms of both its mass flow and size distribution, are described. Finally, its pivotal role in grind control is specified. Our goal is for the reader to come away with a fresh understanding of the role of the circulating load in wet ball milling circuits, including how and why it should be measured and managed.

Feb 22, 2026

By M. Tadie, J. Wiese, K. Corin

The use of potential control in the flotation of ores has been applied in a variety of operations and presents an opportunity for improvement of selectivity and recovery of valuable minerals. Although it is possible to vary the redox potential (Eh) using chemical additives such as sodium hypochlorite or hydrogen peroxide this is more commonly done by varying the pH and dissolved oxygen (DO) concentration. The present study involves an investigation into the effect of varying dissolved oxygen concentration, ionic strength (IS) and pH on the flotation response with the aim of application to a South African lead-zinc ore. In all cases the Eh is measured as a function of the different DO, IS and pH values. The main objective was to achieve selective flotation of galena from sphalerite. The first part of the work was micro-flotation tests conducted on single minerals with galena used as the basis for effect of the factors studied on redox potential and ultimately recovery. The DO was varied by alternating between the use of air and nitrogen as the gas source to the micro-flotation cell. PH was varied between pH 9.2 and pH 11.8 using sodium hydroxide. In the first part of this study a factorial design approach was used to determine the interactive effects of the variables tested, viz. DO, ionic strength and pH, on the Eh and on the recovery. Redox potential was measured using a combination electrode made up of platinum wire and Ag/AgCl reference combination. Recoveries indicated that pH had the most significant effect on recovery and Eh. The influence of redox potential on recovery was found to be of relevance to the condition of high dissolved oxygen concentration and less so at low dissolved oxygen concentrations. It was also noted that that the combined interaction between ionic strength and dissolved oxygen concentration had a positive effect on recoveries, however this was not so with Eh. The chemistry of the ions in solution was observed to play a dominant role on the recovery due to changes in solubility arising to pH modification. The longer term objective of this work is to determine the optimal Eh conditions for the separation of galena from sphalerite.

Jan 1, 2016

By P. L. Sibrell

Electrorefining of Ti in nonaqueous solvents has been studied by the U.S. Bureau of mines as a method for recycling impure scrap Ti. Electrochemical behavior of Ti species was investigated using cyclic voltammetry. Research results showed that Ti metal can be dissolved in polar solvents such as dimethylformamide or dimethyl sulfoxide. However, deposition of Ti from these solvents was not successful. Several solvent systems were investigated for electrodeposition of Ti but no deposits were obtained. Reduction of Ti4+ complexes to Ti3+ proved to be straightforward, but reduction to lower oxidation states could not be confirmed. In dimethylformamide solutions, cyclic voltammetry results demonstrated the reduction of Ti to an oxidation state of less than three, but no Ti metal was identified. In dimethyl sulfoxide solutions containing LiCl, it was possible to deposit Li metal. After adding Ti salts to the solution, electrolysis quickly passivated the electrode. Deposition of Ti was also investigated in solutions of dimethoxyethane and propylene carbonate but, again, no reduction of Ti to oxidation states of less than three occurred. Therefore, the prospects for a nonaqueous electrorefining system for Ti metal do not appear promising.

Jan 1, 2010

On Monday, June 27, 1921, at 6 p. m., twenty-four members of the Institute from. Colorado and New Mexico, left Denver on the Union Pacific for Rock Springs, Wyoming, arriving there at 9:42 a. m., June 28th. The party was met at the depot by the Rock Springs committee and a large number of the local Institute members. The day was spent in visiting the Central Power Plant of, the Union Pacific Coal Company and adjacent mine, the new 'E Plane, the Reliance, Dines, Winton and Sweetwater coal properties in the district. At noon a very elaborate lunch was served in the First Aid Building at the Reliance mine, which was most heartily enjoyed by all. In the evening the members and friends visited the new Rialto theater and saw the pictorial exposition of the' "Sky Pilot". The evening terminated with a dance in the ballroom of the Masonic Temple from 9:30 until midnight, concluding one of the most enjoyable days which the Institute has ever spent in Rock Springs. At 12:3o a. m. the original party, augmented by six members from Rock Springs, were again enroute to Salt Lake City, arriving there at 8:30 in the morning of Wednesday, June 29th. The Hotel Utah had been selected by the local, committee as the headquarters for the convention, and the majority of the -members at once proceeded to that place where the books were opened and the paying of dues and registration of the members were carried on until 11:45 a.m. At noon a majority of the members were entertained at the L. D. S. Tabernacle with an organ recital, which was up to its usual standard of excellence.

Jan 1, 1921

By V. Yahorava

Mintek has developed a non-destructive Resin-in-Leach method for the recovery of Rare Earth Elements (REE) from phosphogypsum (PG) waste dumps. However, PG from different sources was found to be highly variable in terms of REE recovery and physical properties. Development of a pre-treatment process was initiated to improve the robustness of the current REE recovery process in order to render it effective for any type of PG. Extensive research into the mineralogy of REE associations with PG revealed that the majority of REE are trapped inside phosphogypsum clusters which inhibits their recovery. Hydrothermal treatment of PG-containing slurry was found to result in re-crystallisation of gypsum with the release of REE phases encapsulated in it. This process was tested on various PG samples and subsequent REE recoveries improved from 5 to 80%. This approach carries a large potential for unlocking value associated with gypsum dumps worldwide.

By Robert O. Vernon

The discussion of water and pit mining together is most appropriate. In fact, water can be considered a mineral and a well a narrow pit. Thus, of all the mineral resources mined, water is probably the cheapest, most valuable and least valued. The delivered price, including mining, transportation, storage and marketing rarely exceeds ten cents per ton, and our economy would cease without it. The time has come when the public must recognize that the extraction of a mineral resource from the land is a necessary and inevitable result of the industries? attempt to meet the demands of a growing economy. In so much of Florida, the lands mined can, with forethought and planning, be left as improved real estate, water conservation and management lands. On the other hand, the mining industries must face up to the need for the reclamation of land and compact with themselves, appropriate governmental agencies and with the mining states to restore mined lands to usefulness. Of limestone, sand, and clay 90 to 100 percent of the mined material is used, but with planning and specing, these pits, if they penetrate the water table, become valuable as real property. Phosphate, which returns about 70 percent of the mined materials to the pit, can reclaim the land for many purposes.

Jan 1, 1966

By S Nie, I Bergqvist, F Ouchterlony

In blasting, a few or many cracks are driven from the borehole into the rock. But what causes the cracks? The most common theory of breakage consists of two stages; first the shock wave causes radial cracks to form around the hole then the gases penetrate into the cracks, and widen them and make them longer. Another theory presented by Brinkmann suggests that the back damage is primarily controlled by shock and that the gas penetration is the mechanism controlling breakout of the burden. He did his experimental work using blasthole liners. Recent research at SveBeFo has examined this matter further. In a quarry a number of benching holes have been blasted simultaneously. In some of these holes tubular Swellex bolts were inflated and decoupled charges put inside the tubes without stemming. Other holes were identically charged but without the lining. Finally some holes were also stemmed. After blasting the cracks in the remaining rock were studied. There was no difference in crack lengths between holes charged normally (no stemming) and holes where the charges were inside the bolts. On the other hand when stemming was used, the crack lengths increased for some explosives but remained the same for an emulsion explosive. In another set up blasted granite blocks were charged in the same way as above. Then we could also measure the bore hole pressure. The pressure gauge consists of a small carbon resistor inside a steel cylinder. It is called LHM (Location-fixed Hydrodynamic Measuring Cup) and is placed at the bottom of the hole. A smaller exit hole from the bottom is drilled for the cables. The paper presents the technique and the results obtained from both the quarry blasting and the blasting of the blocks.

Jan 1, 2001

By Frederic Laist

IN the spring of 1931 an experiment was made at Anaconda with a small reverberatory furnace, with which was combined a roasting shaft. The arrangement is shown in the accompanying drawing (Fig. 1) and requires but little explanation. The general idea was to roast .flotation concentrates, mixed with the proper fluxing materials, by dropping them down a heated shaft, from which the calcines would enter the smelting zone of the reverberatory furnace through an opening in the roof. The hearth of the reverberatory was 3 ft. wide by 21 ft. long. The roasting shaft was 3 ft. square inside and had an effective height of about 20 ft. . The reverberatory furnace was arranged so that it could be charged either directly through the roof with regular hot calcines, in the usual manner, or by means of the shaft, at the top of which were a feed-ing arrangement by which cold flotation concentrates, suitably fluxed, could be fed continuously and a pipe through which cold air was blown in. Means were provided for distributing the feed over the cross-section of the roasting shaft. At first a mechanical arrangement was used but later it was found that a simple cone served the purpose equally well and gave less operating trouble. On account of the small size of the equipment, it was realized that absolute capacity and fuel consumption figures would mean but little. It was not to be expected that ratios comparable to those obtained in large furnaces could be gotten, and the only way in which any idea could be obtained as to the possibilities of the combination furnace was to run it in parallel with the reverberatory furnace charged in the usual manner and operating without the shaft. The results of such parallel runs are given in Table 1. The amount of oil burned in the reverberatory was purposely maintained at substantially the same rate during both runs in order that the benefits resulting from the shaft might be gaged.

Jan 1, 1933

By Calvin C. Brown

A university is a place to build minds and develop leaders. It provides the tools necessary for the development of new ideas which come from the inquisitive mind and is one of the stepping stones to management responsibilities for the truly ambitious. However, it is not always a financially sound investment! Lately, there have been several articles published on the economic advantages of a college education. These articles tend to average wages together according to education and years of service. Their tabulations generally include the chairman of the board, various vice presidents and plant managers and do not reflect the achievement of the average graduate. They consistently fail to include an analysis of the investment a college education requires. In reality, the bright high school graduate would make more real money over a 20-year period if he went directly to work "on the hill" than he would if he graduated from college. Furthermore, he would find little difference between his wages and those of the college graduate in the period from 20-30 years after high school graduation.

Jan 1, 1971

By Larissa Manso Miguel Gonçalves

A partir da latente necessidade de se manter competitivo perante seus concorrentes, as empresas vêm buscando se diferenciar através de inovações e melhoria contínua de processos. Com base nesse conceito a Logística CSN Aços Longos realizou mapeamento dos seus processos para que fosse possível mensurar sua eficiência. Avaliando o ciclo total do pedido através da medição dos tempos de Coleta (entrada do pedido à oferta de veículo), TPV – Tempo de Permanência do Veículo (carregamento) e Entrega (viagem), foi desenvolvida uma ferramenta para medição do Nível de Serviço da operação. Com a constante evolução do mercado e à elevada exigência dos clientes, isso se torna um diferencial, agregando valor aos produtos e fidelizando clientes. A ferramenta contribuiu para melhora significativa na tomada de decisões quanto às atividades críticas e sua consequente contribuição à satisfação dos clientes.

Oct 30, 2017

By Frank J. Wiebelt

The Mohawk lead-zinc mining in San Bernardino County, Calif., was examined by D. W. Butnor, an engineer or the Bureau of Mines, at the request of Dunton, Ray, and Greenwood, leaseholders. Current operations were on a marginal economic basis, and government aid was sought in an endeavor to outline ore reserves so that production might be maintained.

Jan 1, 1949

By O S. Maluleke

In some deposits valuable heavy mineral quality is poor due to increased mineral surface coatings from higher slimes and more competent sand orebodies. Mineral surface coating can include silica or aluminium rich clay minerals and iron based minerals that render the final product quality off-specification, in this case specifically ilmenite and zircon. Conventional physical beneficiation processes such as magnetic separation, electrostatic separation and gravity separation are not able to remove these surface coatings. Surface dependent separation techniques such as electrostatic separators are affected by these coatings which hinders the rejection of non-valuable mineral from product. Attrition scrubbing is the most commonly used technique to reduce surface coatings, using mechanically induced particle to particle interaction, abrasion and shearing.In many cases it is a challenge to measure the surface removal efficiency of these scrubbing units. Elemental analysis techniques (ie X-ray flourescence) (XRF) in a multi mineral environment are unable to measure surface impurity reduction with enough precision. Mineralogical analysis (in this case Qemscan®) has constraints in terms of sample preparation with highly coated particles being plucked out during block polishing. This paper suggests a combination of laboratory separation techniques coupled with elemental analysis to evaluate the surface removal efficiency. Three different types of feed materials were used to analyse the efficiency of surface removal using production attritioner scrubbers. This approach relates the downstream beneficiation plant’s expected performance with that of the attrition scrubber’s scrubbing efficiency.

Oct 5, 2011

By R. Carter, C. S. Samis

"SummaryThe results of this investigation indicate that the gold in the cyanide tailing of refractory gold cyanides is occluded in fused •particles formed during roasting. This conclusion was reached following microscopic examination of calcines produced at various furnace temperatures with different atmospheres, and a •comparison with calcines produced by decomposing samples of completely sulphated concentrate under conditions such that the maximum particle temperature varied between 6•50°C. and 1,100°C. This comparison showed that the particle temperature during a normal roast may be several hundred degrees higher than the furnace atmosphere, or that the fusion is associated with a low melting (950°C.) eutectic mixture of FeO and FeS.Because of the unavoidable particle fusion during a furnace roast, and because low particle temperatures are essential for gold extraction by cyanidation, aqueous medium oxidation under high oxygen pressures was studied. Gold recovery from calcines produced by this means was over 98 •per cent •compared with a maximum of 80 per cent from furnace calcines.IntroductionMANY arsenical gold ores are called 'refractory' because much ' of the gold cannot be satisfactorily extracted by cyaniding the raw ore or concentrate. Even when such ores are roasted to oxidize .the iron and arsenic and 'release' the gold, often 10 to 25 per cent of the gold present is lost in the cyanide residues."

Jan 1, 1952

By C. M. EYE

IN the spring of 1905 I was employed by Messrs. Bradley and Requa, under our fellow member, Thomas Cox, on the mill plans for the Nevada Consolidated, when an opportunity came to go to the Philippines to erect a small mill on the property of the Benguet Consolidated. This I accepted, expecting to be away eight months or so, but it was seven years before I got back. .I sailed in May, on the Coptic, having as room-mate as far as Kobe, A. E. Drucker, who was going out to Korea for the Oriental Consolidated. It was the first trans-ocean trip for either of us, and we had some rather unusual experiences. This was toward the close of the Russo-Japanese war and the Russian fleet was known to be on the way from Suez to Asiatic waters, but it was a matter of doubt whether they would risk a passage between Japan and the mainland, or take the longer but obviously safer route outside of Japan. The Coptic carried much contraband of war for Japan, so naturally did not care to meet this fleet. No definite word being available at Honolulu, we went to the Midway Islands, but the cable station there had very little information to offer, so we proceeded cautiously toward Japan. On the last afternoon out, we steamed due north at half speed for several hours, and finally sneaked into Yokohama at night, to learn that ' the Russian fleet had met the Japanese the day before and had been annihilated. We sailed over the spot in the Sea of Japan a week later, and when we got to Manila we found three of the Russian boats interned and being guarded by the monitor Monadnock and a cruiser. This was only a matter of form, as the Russians were only too glad to be there for the rest of the war, and the boats could not have gone far anyway, for they were literally shot to pieces. The Admiral's flagship had a hole within 3 ft. of the water line, for ward, through which a man could enter by stooping.

Jan 1, 1929

By Maria Kuttig, Christian Ruback, Gerhard Tober, Petra Maier

"It has been demonstrated that there is a strong relationship between work hardening with various post heat treatment and cyclic deformation behavior of structural steel S275. This study contributes to a project developing a process for the complex forming of steel, which combines rolling and bending. Due to the complex geometry of the final work piece, the deformation degree varies greatly. The forming temperature, as well as post heat treatruent, influences recrystallization processes in dependence of the local deformation degree, resulting in inhomogeneous microstructure of the work piece, which affects the quasi-static and dynamic properties. Cyclic creep and hardening or softening has been monitored during constant amplitude loading at stresses near fatigue strength in normalized condition. Work hardening, stress relief or recrystallization influence the cyclic deformation behavior and produces cyclic creep effects. Cyclic softening or hardening and creep were observed to occur in parallel. To what extent these properties are noted depends on the deformation degree.IntroductionThis work is part of a research project developing a new process for the three dimensional forming of steel. For the final product the fatigue strength influenced by the forming parameters is very important. Due to its complex geometry, the formed final plate has different deformation degrees. This leads to different recrystallization behavior and heat treatruent will have different effects on the microstructure. The peak deformation degree cp of the plate will be around -0.5 what leads to the analysis using rolling from 22 mm to 13 mm of thickness. The quasi-static material properties are very important for calculating the preliminary design. However, work pieces which are cyclic loaded need fatigue tests to describe the in-service material behavior. [l] For the prediction and to guarantee the wanted life-time of the part cyclic deformation tests are important. [2, p.23-32] When it is assumed that the work piece will only loaded in cyclic tension, fatigue testing will be done from zero to a maximum force value. In preliminary tests this value is the tensile fatigue strength from a Smith diagram. During processing, here forming, work hardening takes place resulting in strengthening. Therefore, in further tests maximum load can be increased to monitor cyclic deformation mechanism in more detail. However, to study cyclic creep and hardening and softening data should be evaluate over sufficient life time and should not fracture too soon."

Jan 1, 2013

By H. Sahay

"DISCLAIMER NOTICEThe views and conclusions contained in this presentation are those of the author and should not be interpreted as necessarily representing the official policies or recommendations of the Department of Mines and Energy, Government of Newfoundland and Labrador. ABSTRACTThis paper describes the main testing procedures that should be carried out to evaluate the capacity and capability of the service brakes on the large-size diesel-electric trucks now in common use at open-pit mining operations. Brake testing programs in general are described, and then consideration is given to different techniques of service brake testing, brake performance evaluation, braking energy and typical performance characteristics.IntroductionThe first diesel-electric truck with a capacity of about 85 tons was introduced in 1963 by Unit Rig and Equipment Company of Tulsa in cooperation with General Electric Company, who successfully developed and supplied the most important component- motorized wheels. Since then, its popularity and numbers have continued to grow, and now more than 3700 such units are in operation in mines around the world. In Canada alone, their number is more than 700, including about 150 in the Province of Newfoundland and Labrador. Similarly, their size has also grown from that initial capacity of 85 tons to 350 tons.Although the introduction of the electric trucks proved to be invariably economical, their indiscriminate use was not without severe consequences. Many runaways and even fatalities occurred when the dynamic retarder failed while the truck was travelling loaded down severe grades. The service brakes in such cases proved incapable of stopping runaway trucks, mainly due to their limited capability and the fading caused by excessive heat produced during the act of braking itself. This eventually led the various governments, the open-pit operators and the manufacturers to seriously question the braking capability as well as function of both service brakes and dynamic retarders. Extensive testing"

Jan 1, 1980