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The production of metallic titanium and titanium-rich alloys in forms useful to the engineer involves the use of certain techniques not usually necessary in fabricating the commoner metals and alloys. However, not all stages in the handling and shaping of titanium-base materials require the application of unfamiliar methods. It is the purpose of this paper to indicate where the well-known techniques are applicable as well as to outline the unusual operations which are necessitated by certain chemical characteristics of titanium.In brief, the characteristics just mentioned are manifestations of the very great reactivity of titanium, especially at elevated temperatures. Liquid titanium burns vigorously when brought into contact with air. It also reacts with practically all refractories, causing damage to the latter as well as undesirable contamination of the metal. Even solid titanium undergoes serious superficial contamination when heated above 800°C. in air for more than a few minutes. In addition to an oxide skin being formed, oxygen enters into solid solution in the surface of the metal causing the latter to become hardened and eventually embrittled.Up to date, titanium has been made only on a pilot plant scale by methods which produce a spongy or powdered product. Refractory problems have prevented the development of chemical reduction methods for making titanium in the form of a liquid pool from which ingots of useful size could be cast. Therefore the first part of this paper will cover the consolidation of powdered or spongy titanium. The latter portion will provide a brief description of...

Jan 1, 1950

By A. Brown

This report details work performed and results obtained in a study of the water management aspects of oil shale mining and retorting in the Piceance Creek Basin. Three specific sites were investigated, and optimal water management systems for both conventional and in-situ extraction processes were generated. Water-related legal and environmental constraints on development were identified and the water management schemes were developed in compliance with these regulations. Limitations on shale oil production implied by limited water supplies were evaluated. Potential Basin-wide effects of development were evaluated using a computer model, and mitigation strategies were developed. Recommendations for additional investigation and analyses were presented.

Jan 1, 1977

By D. McCarthy

Contract is a PC-based software program designed to satisfy the main features that have been identified to be lacking from cost estimation systems currently in place in the Australian coal industry. Contract was developed in conjunction with an Australian contracting company to refine the existing core structure used by the company for project evaluation. The key feature of Contract is the availability of analysis functions to explore multiple options within a contract project by altering identified variables. The ability to update project files has been incorporated into Contract to ensure that it is user-friendly and relatively simple to use. Lists of mining equipment and consumables are stored in MS ACCESS database files, along with the supplier details for each item. Each time a project is initiated there is a dynamic link to the database files and the most recent current information is retrieved and linked with the project. Contract provides an option to calculate the changes in metre unit cost as a function of the average development cost. Keywords: Contracting, cost estimation, sensitivity analysis.

Jan 1, 2003

THE Talisman mine is situated on the Waitawheta (pronounced Wytaffetta) river just above its junction with the Chinemuri (pronounced Chinnemurre) river near Karangahake, NZ. The explored reef-bearing portion of the claim includes the angleformed by the junction of the rivers and extends southwards for slightly over a mile (See Plate V.). The country is mountainous both rivers flowing through precipitous gorges.The trig. station on Karangahake mountain is almost directly above the workings on the Bonanza section and is 1680 ft. above river level, the adit from the gorge giving 1200 ft. of backs measured vertically. The officers of the N.Z. Geological Survey are engaged in a detailed survey of the Waihi district and the rocks of Karangahake are under examination. The rocks of the district are andesites and dacites much altered and silicified. One of these exhibits a columnar structure in the mass in the Waitawheta gorge near the surface workings on Taukani hill, also on the southern bank...

Jan 1, 1912

By R. Curtis

To achieve compliance with 2015 EPA Tier 4 Final regulations, which permit only around 10% of Tier 3 particulate matter (PM) and NOx emissions, a number of technologies are being implemented. Use of a fuel borne nanoparticle combustion catalyst reduces the level of PM and unburned hydrocarbons exiting the combustion chamber, alleviating the burden on downstream exhaust after-treatment systems. The impact of an iron-ceria combustion catalyst (GO2) on carbon oxidation kinetics and on diesel engine emissions is presented. The iron-ceria nanoparticles catalyze carbon oxidation at lower temperatures and increase the oxidation rate by a factor of 18 at 400 °C. Engine tests on a generator powered by a John Deere Model engine and field tests on a Cummins ISC 330 tractor truck and CAT 3508B propulsion engines are presented. Use of GO2 resulted in a reduction in PM10 (particulate matter under 10 um) emissions of up to 26% and a hydrocarbon emission reduction of up to 41%. NOx emissions did not increase in these trials and the amount of change depended on engine type. Application of this fuel borne technology for emissions reductions in mining equipment offers significant benefits.

Feb 27, 2013

By Kanchan Mondal, Gopi Bylapudi, Anand Bhagwat

Corrosion of steel roof support systems can cause potential premature failure of the support, thus adversely affecting the excavation stability and rock-related safety. An in-house corrosion test system was designed and developed to test full-length roof bolts for material performance based on tensile load capacity and strength under different corrosive conditions found underground. The roof bolts tested are also used to identify the possible corrosion mechanisms that influenced the bolts’ performance over time. Initially, the most commonly used bolt material in the USA, the ASTM A615 grade 60 steel roof bolts, was tested with and without stresses in a simulated underground coal mining environment for approximately 6 months, and the results are discussed. Localized corrosion forms such as crevice and pitting were mainly observed after testing. The stressed and unstressed roof bolts with and without threads that were tested in alkaline coal mine corrosive environment for 6 months passed their load-bearing capacity as per ASTM F432 test standards. From the results, it is concluded that this test protocol could be applicable to test the material performance of different roof bolt metallurgies and coatings with desired modifications to the proposed methodology for the specific underground mine environment. This paper mainly discusses the test system and protocol and shortcomings of the system and makes recommendations based on the observations and results.

By Kanchan Mondal, Gopi Bylapudi, Anand Bhagwat

Corrosion of steel roof support systems can cause potential premature failure of the support, thus adversely affecting the excavation stability and rock-related safety. An in-house corrosion test system was designed and developed to test full-length roof bolts for material performance based on tensile load capacity and strength under different corrosive conditions found underground. The roof bolts tested are also used to identify the possible corrosion mechanisms that influenced the bolts’ performance over time. Initially, the most commonly used bolt material in the USA, the ASTM A615 grade 60 steel roof bolts, was tested with and without stresses in a simulated underground coal mining environment for approximately 6 months, and the results are discussed. Localized corrosion forms such as crevice and pitting were mainly observed after testing. The stressed and unstressed roof bolts with and without threads that were tested in alkaline coal mine corrosive environment for 6 months passed their load-bearing capacity as per ASTM F432 test standards. From the results, it is concluded that this test protocol could be applicable to test the material performance of different roof bolt metallurgies and coatings with desired modifications to the proposed methodology for the specific underground mine environment. This paper mainly discusses the test system and protocol and shortcomings of the system and makes recommendations based on the observations and results.

This paper deals with the application of table flotation to two unusual mineral dressing problems. Both problems involved the removal of interfering minerals at sizes too coarse to normal froth flotation.The first problem was the removal of arsenical minerals from Broken Hill gravity concentrates without further size reduction. Table flotation without grinding of the original concentrates gave almost complete rejection of the arsenic from the concentrates. A typical test result was a reduction of arsenic in jig concentrate from 0.75% arsenic to 0.007% arsenic.The second problem was to develop a method to produce a high grade calcium carbonate concentrate from coastal dune sands containing about 10% silica and about 80% calcium carbonate. The sands were about 30 mesh British Standard Screen (B.S.S.), and for economic and other reasons it was stipulated that the separation be made without grinding. Again, table flotation gave excellent results. A concentrate was produced containing 99.62% acid soluble material, representing a recovery of 98.69% of the calcium carbonate in the feed with a rejection of 96.44% of the silica.The investigations' were carried out at the Kalgoorlie Metallurgical Laboratory, under the Department of Mines...

Jan 1, 1954

By Adil Aledresse, Louis Mercier, Laxman Amaratunga

"The development of high capacity adsorbents with uniform porosity denoted, MP-HMS (Mercaptopropyl – Hexagonal Mesoporous Structure) using nanotechnology, and their ability to extract gold from solution, is presented. The preparation of highly effective heavy metal ion adsorbents by the incorporation of thiol moieties into the pore channels of mesoporous silica molecular sieves has been the subject of many nanotechnology research investigations. The unique feature of these nanoporous adsorbents is their ability to adsorb gold ions from ultra-low concentration solutions like mine effluent as well as from leached solutions in gold mills. The preliminary studies from laboratory simulated gold solutions show that the adsorption capacities of these materials are also among the highest reported. MP-HMS has shown the capability to adsorb 370 mg gold per one gram of the nanomaterials from Tetrachloroaurate solution (up to 37% of their weight). Experimental studies indicated that the maximum adsorption of gold (as high as 99.9% recovery). The current studies will be extended to investigate the interaction of ionic gold complexes with nanomaterials. Future development of this work may lead to either to replace the conventional CIP/CIL processes or use nanomaterials in tandem with the former, suggesting plausible use of mesoporous material in pulp, MIP or in leach, MIL, as a novel gold extraction process.INTRODUCTIONGold typically occurs at very low concentrations in ores less than 10 g/t or 0.001% (mass basis). At these concentrations the use of aqueous chemical (hydrometallurgical) extraction processes is the only economically viable method of extracting the gold from the ore. Typical hydrometallurgical gold recovery involves a leaching step followed by the separation of the gold bearing solution from the residues, or adsorption of the gold onto activated carbon adsorbent. After elution from the activated carbon the gold is further concentrated by precipitation or electrodeposition."

Jan 1, 2008

By S. Sun

Recent studies on the physico-chemical properties of molten slags and oxide solid solutions of interest is reviewed. The review covers redox and phase equilibria in slags, viscosity, diffusivity, electrical conductivity, kinetics of interfacial reactions between slags and CO-CO2, interfacial properties and phenomena. Some highlights from ongoing work on modelling phase diagrams, component activity, viscosity and electrical conductivity of multi-component slags will be presented and results compared with published experimental data on slags with or without suspended solid phases.

Jan 1, 2004

By D. Potter

In 1990, Freeport Exploration began regional reconnaissance exploration programs in Irian Jaya, the easternmost province of the republic of Indonesia (Fig. 1). Irian Jaya occupies the western half of the island of New Guinea. Freeport was awarded an initial contract of work that totaled 2.6 million hm2 (6.4 million acres). The company was subsequently awarded additional concessions that added 1 million hm2 (2.5 million acres). The concessions require work commitments and periodic relinquishments. Due to these relinquishments, Freeport’s current land position totals 1.9 million hm2 (4.7 million acres). Freeport began the exploration program to locate additional Grasberg deposits, the largest deposit in the Ertsberg district. But the company recognized that other types of deposits could be present in the largely unexplored area of Irian Jaya.

Jan 1, 1999

When the mining and milling of 1100 copper orebody commenced at Mount Isa a satisfactory grade of copper concentrate was difficult to produce. The major concentrate contaminants were fine pyrite and silica, particularly in the minus 10 microns fraction. Studies of the 1100 orebody showed that much of the fine grained pyrite and a proportion of the silica present in the ore contained carbonaceous matter in the form of complete or partial rims and as internal carbon films disseminated throughout grains. The hydrophobic surface property of the carbonaceous material resulted in inherently flotable fine pyrite and siliceous particles.The addition of a 60:40 mixture of nigrosine and dextrine, initially to a prefloat concentrate of the inherently flotable carbonaceous material and finally to the total copper flotation feed, successfully controlled the flotation rates of the carbonaceous pyrite and silica. The objective of a 25 per cent Cu concentrate grade was then achieved without decreasing copper recovery.

Jan 1, 1971

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Jan 1, 1938

The ability to optimise a concentrator from mill feed to final products requires a simulator which integrates comminution, classification and separation modelling. In order to model this range of processes, such a simulator must handle a variety of information about the ore. The AMIRA P9 project has developed a whole-of-concentrator simulation capability which brings together a texture-based model of mineral liberation, quantitative X-ray micro-tomography analysis to measure the inputs required by this model, and a multi-component simulator software framework. In the context of this approach, the term ?multi-component? implies the ability of the simulation to handle many particle properties simultaneously; for example size, composition, density, floatability etc. The simulation software framework provides the means to manage the flow of data around a circuit flowsheet, allowing each process model to access the information relevant to that particular model. A case study based on plant data from a gold-bearing pyrite concentrator is used to demonstrate the capabilities of the multi-component approach in simulating circuits which contain comminution and separation processes.

Feb 27, 2013

By Hugo Escóbar Alvarez

Con el objetivo de optimizar el desempeño del Sistema Experto Fuzzy en la operación de molienda de la Concentradora Cuajone ubicada en Moquegua, se ha desarrollado una investigación utilizando diseños experimentales operacionales. Esta técnica se basa en la aplicación inversa del diseño, es decir, a partir de los mejores resultados de tonelaje históricos hacia los rangos óptimos de las demás variables.

Sep 1, 2017

In a gravity separation device, particle shape, size and density all play a role. The combination of these determines where each individual particle reports to in the viscous fluid, where particle crowding (solids to water ratio) also plays a role. To understand the performance of gravity separation devices in the heavy mineral industry, these particle characteristics need to be measured. There are various challenges in analysing particle density and particle size simultaneously for the purpose of quantifying gravity separator performance, not to mention particle shape. These analytical challenges include the high cost of high-density sink-float fractionation, toxicity of high-density sink-float media, inability of sink-float media to fractionate at densities greater than 4.0 g/cm3, and the time-intensive nature of these fractionations. The use of the detailed particle-by-particle output from Qemscan® particle mineral analyses (PMA) as a fast and cost-effective alternative is evaluated. The size and density outputs from the Qemscan® were employed to characterize the performance of a heavy mineral spiral concentrator as an example. Critical analytical requirements are to be addressed before the Qemscan® output data can be utilized. Keywords Gravity separator, performance, heavy minerals, Qemscan® particle mineral analysis

Jan 1, 2011

By Allison

During the 1980’s, laboratories opened throughout the United States to serve the analysis needs of a rapidly growing asbestos abatement industry. The samples analyzed were either collected during the abatement of known asbestos-containing materials or were suspect asbestos-containing construction materials. Many asbestos analysts received minimal training and used analytical protocols that were industry specific. False positives (reporting a sample as containing asbestos when none is present) went unnoticed or had minor repercussions. The mindset of the industry was to err on the conservative side – it would be better to identify a non-asbestos fiber as asbestos than visa versa. With growing public awareness of the health hazards of asbestos, other materials began to be tested for asbestos content. Rock and ores began to be tested for naturally occurring asbestos by these laboratories using the same protocols or an in-house protocol. Analysts were given no additional training and accreditation, in most cases, it was not required. With no consistency in sample collection, testing protocol or expertise in analysis, significant discrepancies in final results can be expected. If we further complicate this scenario with misidentification of naturally occurring look-a-likes for asbestos, expensive false positives are likely. To avoid the repercussions of misidentification of naturally occurring chrysotile asbestos from look-a-like fibers in rock and ores, correct sampling and analysis protocols with more stringent scientific diagnostic criteria are needed.

Jan 1, 2005

By I. G. Gonçalves

For most industrial minerals, the color is directly associated with economic value. In terms of physics, the principal property that defines the term ?color? is the intensity of light reflected (or transmitted) by an object over the visible band, comprehended between 400 and 700 nm. This reflectance spectrum serves as the starting point for a variety of color-describing factors, the most common in the mineral industry being the brightness (TAPPI, 1977 and 1986) and the L*a*b* system (HunterLab, 2008). Quality specifications for mineral products are usually based on these colorimetric parameters. This market is becoming increasingly more selective and demanding over the quality of raw materials and alongside the traditionally controlled characteristics, such as particle size distribution and chemical composition, a trend exists towards the establishment of increasingly more strict specifications for the optical properties of these materials. This is due to the fact that most plants consuming these industrial minerals incorporate them into products in which the visual appearance is controlled. For these plants, most of them being the manufacturers of plastics, paper, paints, and ceramics, variations in the color of mineral materials result in difficulties to achieve the right color in the final product. Therefore, these plants set strict specifications for colorimetric parameters such as whiteness and yellowness, as well as colorimetric coordinates like L*, a*, and b*. For the manufacturer of industrial minerals, this translates into difficulties simply because many of these parameters are usually alien to the tradition of the mining industry. The main quality parameter in the kaolin industry is brightness, which is a weighted average of reflectance values over the range of 400-510 nm (TAPPI, 1977). Due to the lack of a better property, producers tend to use brightness to also assess the quality of the in situ ore and along the processing operations. However, the unprocessed kaolin is often accompanied by ?contaminant? minerals. For Brazilian kaolins, which are the object of this study, the most important contaminants are hematite (Fe2O3), goethite (FeOOH), and anatase (TiO2). Each of these contaminant minerals has a distinct color and behaves differently during the processing of the kaolin ore. Hematite and goethite in particular are particularly strong pigmenting agents and at concentrations as low as 100 ppm they can make the difference between a high-quality white pigment product for paper coating and waste material. As each Fe-bearing contaminant has a different color and responds differently to processing operations (for example, magnetic separation, chemical bleaching, selective flocculation, and/or flotation in the case of kaolin), the in situ brightness tends to show a poor correlation with the brightness of the final product. Brightness measurements are sometimes complemented with X-Ray Fluorescence (XRF) analysis of Fe and Ti, but the total oxide content provided by XRF is also poorly correlated with product quality because Fe may be in the form of goethite, hematite, or inside the crystalline structure of kaolinite. Thus, a more robust technique capable of distinguishing each mineral phase is desirable. Diffuse reflectance spectroscopy has been used to analyze iron oxide/hydroxide content both qualitatively (Torrent and Barrón, 2003; Liu et al., 2011) and quantitatively (Jiet al., 2002 and 2006). These authors correlate slopes and inflection points at characteristic absorption bands with oxide/hydroxide content in natural soils. The approach presented here involves the extensive use of the Kubelka-Munk (K-M) theory, which has been used for color matching (Schabbachet al., 2009 and 2011) and particle size determination (Otsuka, 2004) in a simplified version. Unfortunately, the scattering constant S is very difficult to measure for dry powders, because the equations require a thin layer of material. Attempts have been made (Gonçalves and Petter, 2007, and Gonçalves, 2009) but the experimental errors tend to be high. Thus, this paper aims to develop a tool for the quantification of contaminant minerals in kaolin based on the K-M theory without resorting to measurements over thin layers. This tool is based on a new two-constant approach, which takes into account differences in scattering between materials over the whole measured spectrum. The experimental dataset consists of the reflectance spectra of mixtures between a bleached kaolin and synthetic Fe pigments.

Feb 27, 2013

By N. L. Ayres

Tendon support systems have been successfully used to stabilize excavations. Tendon support systems are routinely designed using the axial load-bearing capacity of tendons, namely the tensile strength. To attain tensile strength the tendon must be loaded along its length, which often does not occur in practice. Tendons should optimally be installed at 90° to the surface of the excavation to achieve maximum penetration depth, yet this is often not physically or practically possible, and installations at angles less than 90° occur. Furthermore, the intersection of geological features within the rock mass frequently results in complex loading situations on tendons. The position and angle at which loading occurs results in different combinations of tensile and shear forces acting on the tendon, which can impact on the support performance of each unit and ultimately the whole system. All factors that influence the support system should be understood and taken into account to ensure a sound support design. Combination loading situations are further investigated and tested to obtain a better understanding of the mechanisms involved and the effects on tendon load-bearing capacity. Tendon support units were tested at different installation angles to establish the tendon performance, mechanical behaviour, and load capacity during these loading situations. The results and outcomes are aimed at providing rock engineers with additional data and improved understanding of how tendons could perform under certain conditions.

Jan 1, 2014

By J Wesseloo and Y Kim, Y Potvin, G Mungur, D Grant

At the previous MassMin conference held in Sudbury in 2012, the authors proposed a new framework going beyond dilution and equivalent linear overbreak sloughing (ELOS) for stope reconciliation in relation to the planned stope design. More specifically, the new process investigates performance outcomes including rock overbreak (OB) and fill overbreak (FOB), rock underbreak (UB) as well as geomechanical and operational aspects such as blasting, fragmentation and other production data.Based on the findings of the original 2012 study, a comprehensive data gathering program has been undertaken involving design and reconciliation data from 43 stopes mined between September 2012 and October 2014 at BHP Billiton’s Olympic Dam (OD) operation. The new database structure was based on four types of data:stope definition and performance datastope geometrygeotechnical parametersoperational parameters.The new database allows a more in-depth investigation of stope performance. It is now possible to quantify and analyse UB and OB performance from each wall individually as well as the crown. In this paper, the influence of several parameters on recent stope performance at OD is analysed. The underlying reasons for stope wall performance outcomes are discussed in this paper.CITATION:Potvin, Y, Grant, D, Mungur, G, Wesseloo, J and Kim, Y, 2016. Practical stope reconciliation in large-scale operations part 2, Olympic Dam, South Australia, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 501–510 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016