Search Documents

By Mark Fennel

The present paper describes the operation and application of the QEMSCANTM automated applied mineralogy technology and how it is been utilized for long range planning by characterizing and optimizing the primary sulfide reserve while providing operational support of the ongoing secondary sulfide leaching operation at the Cerro Verde Mining Complex in Arequipa, Perú.

Sep 12, 2005

By Clarence Karr

AN EXTENSIVE characterization was conducted on the neutral oil components in a low-temperature bituminous coal tar. A total of tai individual compounds identified with respect to individual isomers, and at least 55 other compounds were indicated to be present. The amounts were determined in all instances. A comparison of isomeric distribution in the tar with thermo-dynamic equilibrium distribution, and kinetic distributions indicated that the composition of the tar largely reflected the structure of the coal from which it was formed. Detailed descriptions are presented for the separatory and qualitative and quantitative procedures for the characterization of the neutral oil component. These include micro fractional vacuum distillation, displacement liquid chromatography, gas-liquid chromatography, countercurrent distribution, and infrared and ultraviolet spectrophotometry. Descriptions are given for the synthesis of authentic specimens of alkylindenes, The ultraviolet and infrared spectra of 134 polycyclic compounds, ranging from alkylindenes to alkylphenanthrenes, either found in the distillable neutral oil, or thought likely to be present, are also given.

Jan 1, 1967

By Tassos Grammatikopoulos, Mike Johnson, Niels Verbaan

Seabed polymetallic nodules, which contain significant quantities of metals key to electrification such as nickel (Ni), cobalt (Co), copper (Cu) and manganese (Mn) can be processed using several different metallurgical processing options, including direct smelting and subsequent hydrometallurgical refining of the copper/nickel matte; ammoniacal leaching (gas reduction or Cuprion); and acid leaching (often reductive). Many of these approaches suffer from reduced cobalt extraction, difficult physical performance, or overall circuit complexity in general, leading to increased risk to the overall project. SGS has considered the pressure acid leaching of nodules for further investigation, as publicly shared data on this processing route stem from the 1970s and 1980s, and are not always easily accessible. This article details the series of tests conducted and provides updated results obtained — high Ni/Co/Cu recovery with limited manganese/iron (Mn/Fe) — as well as comments on the potential treatment options on the product solution and residue.

Sep 1, 2025

By V. Bondarenko

The forecasting of floating earth inrush into the working is to a great extent connected with the investigation of the rock mass stressed-deformed state around the working. The aim of such investigations is to estimate the carrier ability of the protective layer (which is stabilized by the physico-chemical mode of fixing) and to determine it's thickness, which is to be sufficient to present the floating earth inrush into the working. We consider the protective layer to have exhausted it's carrier ability if the rocks of this layer reached the overlimit phase of deformation and it's greater part (section), which adjoins the working. is destroyed up to the limit of the remaining strength. So, the aim of investigations is to determine the size of the rocks inelastic deformation zone in the roof of the working. It is necessary to take into account the presence of water saturated seam in the roof and the overlimit characteristics of the rocks, their ability to lower the carrier capacity up to the level of the remaining strength.

Jan 1, 1996

By Ralph B. S

Bacterial leaching of low grade quartz felspar porphyry copper ore was studied in large-scale laboratory percolation leaching columns.Limitations in the release of soluble copper showed up before fifty per cent recovery, due to occluding precipitates of iron oxides and hydroxides. Precipitates were removed by increasing the acidity of irrigation feed four-fold with respect to sulphuric acid. However, irrigation at low pH (pH 1.5) inhibited copper leaching. Resumption of bacterial leaching at pH2 was achieved by introducing a period of non-irrigation. The results suggest a 'direct' attack by bacteria on the chalcopyrite substrate rather than an 'indirect' ferric-leach mechanism.

Jan 1, 1981

By Mike Cammack, Logan Huppert, Gustavo Azpilcueta

During the summer of 2015, Unisea Inc. sought proposals for the G1 Dock Replacement Project in Dutch Harbor, Alaska. It would be a one year project and construction was scheduled to begin in the spring of 2016. One aspect of the project was the requirement for a layer of armor stone to protect part of the dock. An estimated 30,500 tonnes (37,670 t) of armor stone were needed for the project. The source of rock was the Unisea Quarry due to its proximity to the project and the quality of the stone meeting all the required technical standards.

Jan 1, 2018

By M. A. Cook

Crude titanium metal, produced by the reduction of titanium tetrachloride with magnesium, is contaminated with some excess magnesium end adhering magnesium chloride when it is removed from the reaction pot. The method of vacuum 'purification is described in which the crude mixture is heated in a vacuum at a temperature of about 1,700° F. and the magnesium metal and chloride are volatilized away from the titanium, leaving it practically magnesium-free in a sponge-metal form. The pilot-plant equipment is described in detail, together with the technique of operation and methods of sponge recovery. Operating data is given, which compares ten 24- to 30-hour heats with ton 48-hour heats, and finally, power and labor requirements are discussed. Vacuum purification of raw titanium produced by the Kroll process has boon employed for treating of several tons of raw titanium with results for superior to those achieved by the method of leaching and grinding. The operations described, while on but little more than pilot-plant scale, indicate commercial feasibility of the process, even though it is a batch-typo operation. All equipment is either of standard manufacture or can be readily fabricated from standard materials, and operation of the units can be satisfactorily maintained by semiskilled labor.

Jan 1, 1952

By Gary Jobson

The Mt Todd Gold mine is situated near Katherine in the Northern Territory of Australia. Commissioning of an 8 Mtpa processing facility incorporating a four stage crushing circuit, ball mills, flotation, concentrate regrinding, high rate thickening and CIL processing was commenced during late 1996. A 4.5 M tonne /annum crushing and heap leach facility was commissioned during late 1994, and was subsequently upgraded to a nominal 6 M tonne / annum circuit during 1995. Processing equipment used included primary gyratory, secondary cone and tertiary Barmac VSI crushers. Some of the features of that crushing circuit and heap leach facility were presented at the Randol Perth 95 conference by myself. The location is described as sub tropical with average climatic conditions including 1100 millimetres annual rainfall, predominantly during the December. to March wet season, and 3000 millimetres evaporation and maximum temperatures ranging from around 26 to 46 °C. The main gold occurrence at the Mt Todd site is the Batman deposit, with current published Reserves of some 60 Mt@ 1.20 g Au / tonne ( 0.0425 oz Au / ton ). The primary ore from the Batman deposit is an extremely competent greywacke and is very hard at an average Bond Ball Mill Work Index of26.5 kWhrs/ tonne. Other indicators include a Bond Impact Crush Work Index of 20 kWhrs I tonne, an Abrasion Index of 0.15 and Ultimate Compressive Strength values of 100 - 200 MPa. The main gold occurrence is very finely disseminated free gold (at an average grain size of around 5 micron) within a combination of quartz and mixed sulphide. This gold bearing component is confined to largely parallel veins ranging from 0.5 to 25mm wide within a greywacke matrix. Although the gold is essentially non­refractory, there is a strong recovery versus grindsize relationship due mainly to the liberation characteristics and the relatively low permeability of the host greywacke rock.

Jan 1, 1997

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 J. P. McCullough

In 1943, the Federal Bureau of Mines began a program of thermodynamic investigations of petroleum constituents and related compounds. These systematic, long-range studies, which were conducted in the thermodynamics laboratory of the Bartlesville Petroleum Research Center and are still continuing, have resulted in a substantial quantity of data valuable to the petroleum industry and science in general. As separate phases of these studies were completed, the findings were promptly reported in the scientific press. During the past 16 years, 89 journal articles, giving the results obtained for individual compounds and small groups of related compounds, were published, mainly in the Journal of the American Chemical Society and the Journal of Physical Chemistry. In addition, members of the Bureau staff have contributed six chapters to specialized reference books. This circular, prepared in response to many requests, lists these 95 published papers, giving an abstract of the contents of each, as well as titles, authors, and literature citations. The journal articles are listed in the order of their preparation, which closely approximates the chronological order of their publication; hence, the item number to the left of each citation corresponds to the assigned contribution number. For the convenience of the reader, the abstract section is followed by a condensed bibliography, arranged alphabetically by senior author and keyed to the abstracts by appropriate contribution numbers in parentheses after the entry.

Jan 1, 1961

By CIM Environmental, Social Responsibility Society

Within the mining industry, the pathway from exploration, to planning, construction, operation and closure has become more complex over the last few decades. The current financial, environmental and social influences present the mining industry with unprecedented challenges and opportunities. In addition, international environmental and social reporting standards and codes are becoming increasingly robust. The reporting requirements provide an added impetus for issuers to effectively manage environmental and social impacts and risks. Reporting requirements also provide the opportunity to be transparent. The intended audience for these Environmental, Social and Governance (ESG) Guidelines for Mineral Resource and Mineral Reserve Estimation includes practitioners, industry participants at all levels of skill and experience, corporate management and board members, government agencies, academic institutions and interested parties. For practitioners, this document provides underlying key principles of environmental, social and governance practices. The ESG Guidelines provide guidance for those using environmental, social, governmental and governance information when preparing and implementing mineral exploration programs and contributing to the preparation of mineral resource and mineral reserve estimates for mineral properties that are either at the study stage (i.e., scoping / preliminary economic assessment, pre-feasibility, or feasibility studies) or in operation. The guidelines can also be used to help mineral resource and mining companies apply good practice to manage their environmental and social risks and opportunities. Companies can identify and retain appropriate professionals to prepare environmental and social materials to support company studies. The guidelines are also a resource for companies developing effective environmental and social management strategies at any project stage. This document is not intended to be prescriptive and is not intended to provide exhaustive guidance on what to consider in terms of environmental, social, legal and governmental modifying factors in the preparation of MRMR estimates. Rather, it is intended as general guidance to assist companies and practitioners in considering and applying these modifying factors for MRMR estimates. This document is also not intended to guide environmental and social impact assessment (ESIA); however, the measures needed to manage impacts help inform the constraints and costs for defining mineral resources and mineral reserves and inform the costs and schedules of mineral project studies. All documentation of MRMR estimates made by an issuer and intended to be, or reasonably likely to be, made available to the public in a jurisdiction of Canada must comply with the requirements of National Instrument 43-101 Standards of Disclosure for Mineral Projects (NI 43-101), as amended from time to time (Canadian Securities Administrators, 2016a and 2016b). Disclosure is not addressed in these ESG Guidelines. Determination of what to include in disclosures is defined in the applicable Securities’ legal frameworks. Appendix A presents a summary table showing the linkage of the principles and topics in these ESG Guidelines to the potential effects on project costs, schedules, government permits and approvals, social licence to operate and financing.

Sep 8, 2023

By Orlando E. Romig

As metals and alloys are composed of an aggregate of allotriomorphic crystals or grains, each possessing an individual orientation, the physical characteristics of a metal or an alloy are closely related to the properties of the individual crystals. The preparation and study of single metallic crystals are, therefore, matters of considerable importance. The advent of the X-ray spectrograph as a valuable metallurgical tool has magnified the importance of this subject, because the interpretation of some X-ray spectrographs is difficult unless single crystals are used in these studies. Previous Work The first paper, as far as the writer knows, on the behavior or preparation of single crystals of metals is by Baker.' He describes the behavior of extruded wires of sodium and potassium. These wires, when pulled in tension, instead of showing the usual conical fracture common to most metals, had a chisel-shaped fracture when they were broken. I and 11, Fig. 1, have a similar fracture. Baker checked his results by preparing single crystal wires from molten sodium and potassium and observing their properties. He pre- pared the wires by filling glass tubes, under oil, with the molten metal. The surfaces of the strained wires showed slip bands of remarkable clearness of which photographs are shown in his paper. He concluded that these wires were single crystals and "that the portions of the metal brought into play are cubes. Such cubes, when placed so that a plane through two opposite edges was parallel to the axis of the wire, would allow of lateral contraction by faces gliding over one another in one direction only and not in the direction at right angles."

Jan 1, 1927

By Kimio Ilagaki

The distribution ratios of Ag, Pb, As, Sb and Bi for the Cu2S-FeS or Ni3S2-FeS matte I FeOx-SiOl, FeOx-Si02-CaO or FeOx-CaO slag equilibration in a MgO crucible were determined experimentally at 1523 ~1573K under controlled partial pressures of S2 and 02 at given PS02 of 10.1,50.7 and 101.3 kPa(O.I, 0.5 and I atm), and the observed dependency of distribution ratio on the matte grade, S02 pressure and slag basicity were analyzed on the basis of thermodynamics.

Jan 1, 2003

By Cecil Q. Cupps

Results are presented of a comprehensive study of the characteristics of the original oil in the Weber sandstone reservoir, Rangely oil field, Colorado. Through the medium of subsurface sampling, adequately representative samples of the original reservoir oil were obtained from many parts of the reservoir over a period of 5 years concurrent with active development of the reservoir. Data of differential gas liberation, pressure-viscosity, and. pressure-volume-temperature relationships are shown for 12 subsurface oil samples. Data also are given of reservoir pressure and. temperature, composition of liberated or solution Gas, composition of 22 produced-gas samples, and Hempel analyses of crude-oil samples from 18 wells. The characteristics or physical properties of the 12 subsurface oil samples, as determined by laboratory analyses, were correlated with elevation of the top of the Weber sandstone. These relationships of oil characteristics to elevation in the reservoir show that only the oil in contact with the initial gas cap was gas-saturated at the existing pressure and temperature. The characteristics of the original reservoir oil were marked by an appreciable decrease of saturation pressure and solution gas-oil ratio and increase of viscosity and density with depth below the gas-oil contact. The composition of solution gas and of' produced was also was found to vary with elevation of the oil in the reservoir.

Jan 1, 1951

By K. E. Yassin, A. Yehia, M. Amar

Phosphate fines (size ≤ 45 μm), from the Red Sea Region, Egypt, were subjected to beneficiation process to recover the phosphorite grains from such fines. The sample is characterized by low P2O5 content (18.78%) associated with gangue minerals such as silica (22.77% SiO2) and carbonate (2.01% MgO) indicating its low grade. Phosphate pre-concentrate was prepared by gravity separation, using Falcon, where 63.37% of the phosphate, with 24.94% P2O5, 1.46% MgO, and 10.54% SiO2, was firstly recovered reducing the mass flow to the subsequent beneficiation process. However, the gravity tailing was the feed for the reverse phosphate flotation using bench scale column flotation where oleic acid was used as a carbonate gangue collector and amylase enzyme as a phosphate depressant. Under the appropriate flotation conditions (0.1% amylase, 5·10−4 mol/dm3 oleic acid, and temp. 30 °C), phospho-concentrate assaying 0.61% MgO, 13.14% SiO2, and 27.85% P2O5 with a P2O5 recovery of 55.45%, was finally obtained without the use of expensive depressants, e.g., phosphoric acid or sodium silicate. A tentative flow sheet for the whole process was postulated.

By R. G. Henley

Mount Isa copper concentrate was combusted in a laminar-flow furnace. The conditions simulated those likely to be encountered in flames in flash smelters of the Outokumpu (air as oxidant) and INCO (oxygen as oxidant) types. The range of conditions studied was as follows: T 400-1400°C, 02 0-100%, SO2 0-95% for residence times up to 0.23 s. The distribution of sulfur, arsenic and lead between the particles and the gas phase was studied. Combustion was very rapid provided the concentrate was adequately dispersed, i.e., no agglomerates. The importance of the latter is discussed. It was possible to oxidize 80% of the sulfur present in the con¬centrate after only 0.1 s reaction time at 1000°C in an atmosphere contain¬ing 8.5% 02 and 12.5% SO2. Best volatilizations (90% of the As, 52% of the Pb) were obtained under localized conditions attained in an air-type flame. Average volatilizations were: air-type flame, As 50%, Pb 32%; oxygen-type flame, As 40%, Pb 30%. The substitution of oxygen for air reduced the arsenic volatilization. The products of combustion were mainly cuprospinel and cuprite; small inclusions of elemental copper were found in some of the particles. At high temperatures, there was a loss of copper due to vaporization of CU( g) CuO kg) (g)

Jan 1, 1983

Geological information is essential for a diversity of public and other purposes, including land use planning, hazard mitigation, and the exploration and sustainable use of natural resources. This is especially important in New Zealand, where the complexity of the geology is due to its position on an active plate boundary - the ultimate cause of earthquakes, mountain building, subsidence and volcanic activity. The geological setting also controls the origin and distribution of New Zealand's varied mineral and energy resources. Providing information about the origin, quality and quantity of mineral resources has long been seen as a key function of national geological organisations such as the Institute of Geological and Nuclear Sciences. Such information is essential for wise land-use decisions under the Resource Management Act. One of the major goals of the Institute is to quickly and effectively disseminate research results to interested users. The most effective and internationally accepted method of presenting geological data is by means of geological maps, which show the distribution of rock types and structural features at the surface. Most countries have ongoing gelogical mapping programmes, and in recent years the need for up-to-date, reliable information has led to a trend to accelerate basic geological mapping (eg US National Geological Mapping Act 1992; Australian National Mapping Accord 1990; Plan 2000 in the UK). Over the last 25 years, the Institute of Geological and Nuclear Sciences and its predecessors (NZ Geological Survey and DSIR Geology and Geophysics) have concentrated on detailed mapping of priority areas selected on the basis of economic and scientific interest. This has included remapping of Nelson-West Coast and Coromandel, regions with high mineral potential, for which 1:63 360 or 1:50 000 maps have been prepared.

Jan 1, 1994

By Paul F. Ziemkiewicz, Aaron Noble, Christopher R. Vass

The conventional rare earth element (REE) industry has historically sought to develop ore deposits where geologic processes have produced mineralized zones with commercially attractive REE concentrations. These deposits are extremely uncommon, particularly in the USA. Given the criticality of these materials and the need for sustainable domestic supply, the current research seeks to leverage other autogenous processes that lead to concentrated REE resources. One such process is the generation of acid mine drainage (AMD). AMD is very common in many coal mining districts and results from the exposure and oxidation of pyrite during mining. During the generation and migration of AMD, liberated sulfuric acid mobilizes several metal ions including REEs. Treatment of AMD is required under U.S.C §1251, the Clean Water Act, and often consists of neutralization, oxidation, and metal hydroxide precipitation. To investigate the deportment of REEs during this process, a field sampling campaign was undertaken, whereby the concentration of REEs in AMD and AMD precipitates was measured directly. In the nine sites evaluated in this study, the REE concentrations of the precipitates varied from 29 to 1286 ppm with an average of 517 ppm among the sampled sites. The individual elements were enriched compared with the associated bulk Northern Appalachian (NAPP) coal material by factors ranging from 3 to 15. Furthermore, the distribution of REEs in all precipitate samples favored the heavy REEs (HREEs) when compared with traditional REE ores. This research represents the first part of multi-part research endeavor to characterize, classify, and determine the practicality of refining REEs from AMD and its by-products.

By Paul F. Ziemkiewicz, Aaron Noble, Christopher R. Vass

The conventional rare earth element (REE) industry has historically sought to develop ore deposits where geologic processes have produced mineralized zones with commercially attractive REE concentrations. These deposits are extremely uncommon, particularly in the USA. Given the criticality of these materials and the need for sustainable domestic supply, the current research seeks to leverage other autogenous processes that lead to concentrated REE resources. One such process is the generation of acid mine drainage (AMD). AMD is very common in many coal mining districts and results from the exposure and oxidation of pyrite during mining. During the generation and migration of AMD, liberated sulfuric acid mobilizes several metal ions including REEs. Treatment of AMD is required under U.S.C §1251, the Clean Water Act, and often consists of neutralization, oxidation, and metal hydroxide precipitation. To investigate the deportment of REEs during this process, a field sampling campaign was undertaken, whereby the concentration of REEs in AMD and AMD precipitates was measured directly. In the nine sites evaluated in this study, the REE concentrations of the precipitates varied from 29 to 1286 ppm with an average of 517 ppm among the sampled sites. The individual elements were enriched compared with the associated bulk Northern Appalachian (NAPP) coal material by factors ranging from 3 to 15. Furthermore, the distribution of REEs in all precipitate samples favored the heavy REEs (HREEs) when compared with traditional REE ores. This research represents the first part of multi-part research endeavor to characterize, classify, and determine the practicality of refining REEs from AMD and its by-products.

By LeRoy D. Loy

The disposal of excess overburden from surface mining can be accomplished by use of a reclamation technique entitled head-of-hollow or valley fill. This report attempts to assess current valley fill regulations and practices, identifies inherent benefits and deficiencies, and develops concepts to enhance fill technology.

Jan 1, 1978