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By A. Atef

Vulnerability is a measure of the extent to which a community, structure, services or geographic area is likely to be damaged or disrupted by the impact of particular hazard. Current asset management practices focuses on studying factors that affect performance of isolated infrastructure networks and model a set of actions to control the expected performance of these networks. This approach ignores the underlying spatial and functional interdependencies among these infrastructure networks and their vulnerability. The purpose of this paper is to introduce a new method that recognizes the effect of spatial and functional interdependencies on vulnerability rating of water, sewer and road networks. The proposed method consists of: 1) risk assessment model, 2) interdependency assessment model and 3) vulnerability assessment model. The risk model is composed of two modules: 1) water and sewer risk module and 2) road infrastructure module. The water and sewer risk module will cluster these assets into three risk categories based on environmental, social, operational and economical factors. The road infrastructure module will cluster road assets into three risk categories by using rational factorial technique based on road type, serviceability index, traffic load, and freeze and thaw index. The interdependency model will deploy the risk ranking to perform geospatial analysis in ArcGIS which results in determining the interdependent layers of waters, sewers and roads. The vulnerability model will deploy fuzzy neural networks technique to determine the vulnerability rating based on spatial and functional interdependencies. The fuzzy neural networks are utilized to overcome the lack of historical data and incorporate experts? preferences for establishing the knowledge base for vulnerability assessment. The expected contribution of this framework is to aid decision makers in understanding the interdependencies between civil infrastructure assets and to which extent such interdependencies can compromise assets performance.

Aug 1, 2013

By M. K. Aly

"ABSTRACTThis paper briefly describes the mining method proposed for the iron ore deposits in Wadi Shatti, western Libya. The iron ore produced will be used in the steel plant at Misurata on the Mediterranean coast. GeologyThe Wadi Shatti is located in the central part of western Libya. Flat iron-bearing sedimentary rocks are exposed with remarkable regularity in this valley. It occupies an area 200 km long by approximately 20 km wide trending in an eastnortheast direction between Jabal Fazzan in the north and Zel1af Sand Dunes in the south (Fig. I). Only a part of this valley has been ful1y explored by drilling on a 400- by 200-m pattern in an area of 18 km2 south of the town of Taroot. Farther to the south, no exploration by drilling can be done due to the presence of sand dunes .The iron-bearing bed is about 10to 15m thick, with a dip of 2 to 4 degrees in a southerly direction . The overburden consists mainly of clayey sandstones, 4 to 5 m thick, in the northern part, increasing to 35 m in the southern part. The iron ore bed consists of three different layers, from the floor upward: (1) Lower Reduced Ore (LRO), having a varying thickness of 1 to 7 m; (2) Magnetic Ore (MO), with a thickness varying from 4 to 12 m mainly in the central part of the area; and(3) Upper Reduced Ore (URO), with a bed thickness varying from 0 to 7 m."

Jan 1, 1980

By B. D. H. Knights, N. B. du Preez

The recovery of the economy of the Democratic Republic of Congo has allowed for the rapid increase in production of copper from this region, while the increased price of cobalt continues to support the recovery of that country’s economy. This has enabled the modernization of the process technology used, particularly the change from direct electrowinning of copper to solvent extraction-electrowinning. With this change has come a variety of technical challenges in optimizing the recovery of cobalt from these sources. In this paper, we discuss aspects of the flowsheets for the production of cobalt from the ores of the DRC and Zambia, highlighting the technological improvements that have been made. Following this description of the practice, we assess the challenges of further improving the recovery and purity of cobalt from these sources. INTRODUCTION The African Copperbelt (Figure 1) is by far the biggest producer and holds the greatest reserves of cobalt (Sheed, 2015). However, the ores of this great mining region are extracted primarily for their copper content, and cobalt is a by-product. The ratio of copper-to-cobalt is between 6 and 20 to 1, with the ores from the DRC richer in cobalt than those from Zambia. The overall supply of cobalt, shown in Figure 2, is increasing due to an increase in demand for its use as a battery material. Cobalt is used in superalloys, hard metals, pigments, catalysts magnets, tyre adhesives, lithium-ion rechargeable batteries, and wear-resistant coatings, amongst others. Although these generic categories persist, Figure 3 shows how the relative usage of cobalt is changing due to the uptake of electric vehicles in China and Europe. Cobalt is a key element in lithium-ion batteries, and because it is widely anticipated that electric vehicles will be legislatively encouraged, it is anticipated that the demand for cobalt will rise. This anticipated increase in demand resulted in an increase in the price for cobalt, to which suppliers responded over-eagerly, and the price has dropped dramatically in the first few months of 2019, as shown in Figure 4. However, there is a clear cycle of price peaks in cobalt’s history.

Jan 1, 2019

By J. I. Jr. Moore

Many articles have been written about the various operations of Britannia mines and mill, as well as treatises on the geology and ore deposits. A partial list of these papers is given below. Most of these papers have covered well the history of Britannia, and have included a thorough discussion of the geology and ore deposits; therefore, in this paper, no account of these subjects. is necessary. However, a short description of the ore deposits will be given as an aid to a clear understanding of the descriptions of the various mining methods. The Ore Deposits The ore deposits at Britannia occur along a shear zone and are five in number, named for the claims in which they lie, as follows: Jane, Bluff, Fairview, Empress, and Victoria. Each of these deposits is called a mine, as they are separated by 500 to 1,000 feet of barren ground. The Jane mine, although the first producer of the Britannia group, has not been in operation for a number of years. The deposit is a silicified replacement in sediments; with very little evidence of shearing. The Bluff deposit is a highly silicified replacement in porphyry, massive and irregular, very hard in the upper 600 feet with practically no shearing, and softer within chlorite schist in its lower 1,000 feet . The Fairview deposit consists of a series of twelve distinct veins or lodes, rather lenticular in shape, and occasionally merging.

Jan 1, 1928

By P. M. Solozhenkin, O. I. Ibragimova, I. P. Solozhenkin

Molecular models of complexes of poorly studied bismuth, gold, and arsenic mineral clusters and reagents were created for use in collector activity forecasting using Chem Bio 3D and ChemOffice2005, with optimization by MM2. The density functional theory approach was used to determine HOMO, LUMO, SOMO, and total energies, atomic charges, and s, p, d- populations for various compounds. The structure-based virtual screening (SBVS) and docking technique was proposed to reduce the vast number of compounds to a more manageable number for selection of potential flotation candidates. The prognosis of collector activity evaluation (PCAE) strategy was proposed as a consistent approach to estimate the interaction between a collector and a mineral cluster as the difference between the total energy and sum of cluster energy and collector energy to search the analogue of butyl xanthate. The negative relationship between PCAE and flotability was shown. The combinations of dialkylamino sulfhydryl collectors can be considered as prospective reagents for gold-bearing sulfide ore flotation. These results were confirmed by experimental data in ore flotation. The increase in recovery of gold and bismuth with the aid of a combination of reagents has been established and additional cyanidation of tailings has been avoided.

Jan 1, 2016

By O. Benavente, M. C. Hernández

Selenium is obtained mainly from copper anode slimes, which is a by-product of the copper electrorefining process. Selenium is present in copper anode slimes as silver and copper selenides. Traditionally, selenium has been obtained by pyrometallurgical processes; however, hydrometallurgy has now been incorporated either full or partial to the conventional process. Some hydrometallurgical processes are been developed and used at laboratory level an industrial scale. This document describes theoretical background and results of characterization and dissolution of selenium from a decopperized anode slimes in an alkaline oxidizing system. The results have indicated that the oxidizing leaching process reaches a practically complete dissolution of selenium (up to 90 %); the undissolved portion is due to the generation of a AgCl around the particle surfaces that delays the progression of the reaction. The results indicated that 90% of selenium extraction can be obtained by dissolution under moderate conditions of pH, temperature and reagent concentration in oxidizing medium. INTRODUCTION Selenium is distributed in the earth's crust in most rocks and soils. Selenium is essential, as it has wide range of applications in the medical and food industries as well as, used in semiconductor, sensors and photochemical devices. Selenium is rarely found in the native state, 90% of selenium is obtained from copper anode slimes, which is a byproduct of the copper electrorefining process (Lu, Chang, Yang, & Xie, 2015; Xiao et al., 2017; Yang et al., 2018). In anode slimes, selenium is present as an intermetallic compound, as Ag-Cu selenides. Currently, selenium is recovered from the anode slimes via hydrometallurgical and pyrometallurgical processes (Lu et al., 2015). The traditional pyrometallurgical method recovers selenium effectively, but faces difficulty as a result of increased energy costs and strict environmental regulations associated with the process (Li, Yang, Jin, Chen, & Tong, 2017). Therefore, hydrometallurgical processes are proposed in oxidizing medium such as nitric acid, alkaline leaching with sodium nitrate, wet chlorination and pressure leaching, amongst others (Hait, Jana, & Sanyal, 2012; Kim & Wang, 2010; Xiao et al., 2017; Yang et al., 2018).

Jan 1, 2019

By Gordon. I. M., J. Blackshaw

"The wet part of the Hollinger mill is housed in two buildings, the grinding plant and the treatment plant. In the grinding plant there are four 7xl5 ball mills which grind the ore to 60 per cent through 200 mesh. There is also one 7xl5 ball mill which grinds table concentrate to 9 5 per cent through 200 mesh.The primary classifier overflow is pumped to the treatment plant where it passes over shaking tables, producing a concentrate and a tail. The concentrate pulp is pumped to the grinding plant for secondary grinding. The secondary classifier overflow is pumped back to the treatment plant where it is thickened in two 40xl 5 tray thickeners and agitated in four 20x24 mechanical agitators arranged in series of two (with 2 spares).The table tail pulp is thickened in nine primary 40xl5 tray thickeners (with 2 spares). The thickened table tail pulp and the concentrate agitator discharge pulp are mixed and pumped to four rows of 15x45 pachuca agitators, arranged in series of five tanks.The pachuca discharge pulp is divided. The smaller part goes to two rows of 3-step decantation using 40xl5 tray thickeners (with 2 spare rows). The larger part goes to six 14xl6 drum filters. The repulped primary filter cake and the thickened pulp discharged from the decantation rows are fed to eight 14xl6 drum filters. The secondary filter cake is mixed with water and pumped to the tailing line."

Jan 1, 1968

By Gary Pattrick

A new class of spongy Au catalysts is studied for the selective catalytic reduction of NOx by propene under leanburn conditions. The spongy catalyst is an unsupported powdered Au that consists of micrometer particles (~5 microns) that have nanometer scale (~10 nm) internal skeletal structures. The effects of alloying 1 ? 50 atom % platinum group metals (M= Pt, Pd, Rh) and 5 wt% first row transition metals (M = Ti, Mn, Fe, Co) were studied. Even low additions of PGMs (1 at.%) cause significant shifts to lower temperature regions of activity and the largest shift is obtained for Rh. For Rh this is interpreted as a strong synergistic interaction between Rh and Au. Possibly related to the Rh effect, Co is the only other metal studied that lowers the temperature of NOx reduction. The other first row transition metals inhibit the reduction reaction.

Oct 1, 2003

By A. M. Bell

"Hallnor mine is in the township of Whitney, Porcupine district. To date, its production of gold has been second largest in the east Porcupine field. Ore was discovered in the property in 1936 by diamond drilling in overburdened country. This drilling was undertaken by Noranda Mines following the discovery of ore in conglomerate at Pamour 1 mile to the east.Milling commenced at the Hallnor in June 1938, and to the end of 1945 432,000 oz. gold had been produced from 889,000 tons of ore, giving an average recovery of 0.49 oz. a ton.The West mine of Pamour, the Broulan orebody, and the veins on the Hallnor and Bonetal are all parts of a mile long vein system that has been separated into three sections by cross faulting. In consequence, they could well have been described in one paper. In treating them individually the viewpoint obtained from each may lead to conflicting opinions, and any conclusions advanced in this paper on the general structure should be modified by the conclusions advanced in papers on the neighbouring properties.GENERAL GEOLOGYRock FormationsThe Hallnor orebodies occur within 400 feet of the contact between lavas and sediments, and may lie in either lavas or sediments. The lavas near the ore consist of flows of pillowed andesite and one flow of more acid and less sheared and chloritized lava locally named trachyte. These flows strike east-west and dip steeply. At the surface on the east side of the property the volcanics have been intensely altered to a massive carbonate rock having a north-south thickness in excess of 1,000 feet . This carbonate body extends west across the property with a plunge of 45° (Fig. 1)."

Jan 1, 1954

By J. Dubinski

This paper describes the key circumstances of the underground coal gasification (UCG) process, which is planned to be carried out in the Polish hard coal mine ?Wieczorek?. The construction and field tests of a UCG pilot plant have key issues that need to be addressed to realize the research project goal: the elaboration of a highly effective technology of fuel and electricity production. The project will conduct several monthly tests of gasification in the pilot geo-reactor, which will be constructed based on the results of laboratory tests. The realization of the process requires numerous appropriately prepared actions adjusted to natural conditions in the hard coal deposit. Based on scientific principles, it is necessary to elaborate the procedures related to the location of the UCG installation (including its legal and safety aspects), and to perform a technical risk analysis. In addition, it is necessary to determine the required mining, geological, technical, economic and organizational circumstances, while at the same time considering the real but constantly changing process conditions.

Aug 1, 2013

By Frank D. Shepherd

THE Gunnar Gold Mines property is on the west shore of Beresford lake, in the Rice Lake mining division, southeastern Manitoba. Gold was first discovered in place in the Rice-Beresford Lakes area in 1911 on the Gabrielle claim, now included in the San Antonio Mines property at Rice lake. Following an eastward trend of favourable prospecting ground, promising showings were next staked in the vicinity of Long lake during the years 1915 and 1916. At that time, William Walton and associates, among them Gilbert LaBine, staked the Eldorado vein, north of Long lake, and Eldorado Gold Mines, Limited, was formed to develop the property a Company that, later, was to become widely known through successful operation of its radium-silver mine at Great Bear lake, Northwest Territories. Continuing eastward from Long lake, Walton and his partners, Gunnar Berg, Leo Seaberg, and Wm. Quesnel, staked claims during the years 1920-24 in the vicinity of Beresford lake which, later, were to become incorporated into the Gunnar Gold Mines property. The presence of gold-bearing quartz on these claims had been known from the time they were staked, but an opportunity to consolidate them into a group was not forth-coming until early in the year 1933. Although promising gold showings had been disclosed during the performance of assessment work on individual claims, no continuous mineralization having mine-making possibilities was discovered until after the consolidation of the entire group. From this stage onward, progress was rapid. Active exploration was begun on August 1st, 1933, and late in October James Houston reported favourably on the property. On October 27th, Gunnar Gold Mines, Limited, was incorporated in the Province of Ontario to develop and operate the property. The Company is also registered in Manitoba. The authorized capitalization is 3,000,000 shares of $1.00 par value. Gilbert LaBine was appointed president of the Company, with James Houston as mine manager. Following completion of a diamond-drilling programme, planned in 1933, it was decided to install a mine plant capable of carrying development to a depth of 1,000 feet. A transmission line, 5 miles in length, was built to the Great Falls-Central Manitoba line of the Manitoba Power Company, Limited.

Jan 1, 1939

By J. P. Nowlan

"This paper is an attempt to outline the structural problems at the Cochenour Willans mine, in so far as their details have been tentatively worked out. It must be emphasized that there are considerable data that can be interpreted in more than one way, and that further work may modify or completely change some of the hypotheses presented herein. Certain features, however, are sufficiently constant to warrant reliance on them when searching for extensions of orebodies.As the individual ore shoots usually have relatively small dimensions, but are often very high grade, structural details are of more than usual significance in laying out a mining programme. An illustration of this is a small shoot recently located and mined as a result of studying a minor slip cutting off a part of high grade gold ore in No. 319 stope. The shoot, which is bounded on three sides by slips, and on the fourth by the original stoping, was roughly triangular in plan, 20 feet on the base, and 40 feet in length. The average width mined was 4.5 feet, but the gold obtained totalled over 1,800 oz.The property lies in Dome township, east of McKenzie island, and consists of an original group of thirteen claims acquired from the Cochenour Willans syndicate, plus one additional group of five claims obtained by purchase from the Kelson Red Lake Gold Mines, Limited, and one other claim that rounds out the southeast corner of the block.The claims of the original group were staked by W. M. Cochenour, Dan Willans, and Horace Young, during 1926 and 1927. The Cochenour Willans Syndicate was formed in 1928, and until incorporation of the present Company work was carried on at varying intervals by several different interests, including Ventures Limited, Hollinger Consolidated, who sank a shaft to open up the 150-foot level, and by the Syndicate itself. The first ore from the property was shipped to the Gold Eagle mill by the present Company in 1939, and amounted to 4,959 tons, from which 2,360 oz. gold was recovered. The first brick was poured in December, 1939, and production has been continuous since that date. To the end of June, 1946, gold having a value of $5,982,000 has been produced from 345,033 tons of ore treated."

Jan 1, 1954

By J. P. Thomson

Magnesium alloys are steadily improving their market share as structural components especially in the transportation sector. Therefore, there is a great deal of interest from the automotive and the metal casting industry to develop viable economic casting processes for magnesium-base alloys. This paper summarizes the preliminary results on the continuing projects within CANMET-MTL on casting processes such as gravity and low-pressure casting in sand molds, permanent molds and lost foam.

Jan 1, 2004

Productivity and efficiency of diesel-powered underground trucks and LHDs can be enhanced through the application of a range of advanced technologies. In addition, these machines are subject to ever more stringent emissions control requirements. This paper will review how various technologies can improve usability, maintainability, and performance of LHDs, through a number of examples. The use of instrumentation and monitoring to understand the role of operator practice on mucking efficiency, as well as the use of finite-element analysis to evaluate structural design, and the use of control techniques to modify operator inputs and hence decrease power consumption, will be presented.

May 1, 2002

By G. Bonin, A. Jamal, G. Preciado, S. Gillis

"Accurate, easy to obtain, and reliable methods of measurement are the cornerstone of shaft and tunnel developments - during their sinking, operation and maintenance, or in some cases, remediation. This paper presents a new methodology to capture existing shaft conditions in such a manner that they can be transferred from the field to a digital copy, where they can be stored and used for engineering design purposes in a space not directly affected by the costs associated with schedule and equipment performance. The methodology utilizes basic principles of excavation alignment (plumb lines and survey instruments) while adding modern LiDAR, geolocation and survey control tools that can more completely capture the surrounding environment. The complete cycle of collection, processing, and delivery of pertinent information underground can take under an hour. During sinking, capturing data as a live stream measurement and being able to assess the alignment of the shaft liner can be critical to meeting rigid design tolerances. As sinking progresses, small changes in alignment or liner deviations can be captured and immediately corrected. Likewise, post-construction as-built conditions can be recorded and digitized, which will allow the mine personnel to compare the proper working condition to the actual condition years later. Observed changes can be identified and planned as future shaft repair works. This methodology has been developed and successfully deployed during the on-going sinking works of the two shafts at the Jansen Potash Project in south-central Saskatchewan and is described in greater detail in this paper.INTRODUCTION Light Detection and Ranging (or LiDAR) scans of the BHP Jansen Production and Service shafts during construction identified sections of both shafts where the internal radius of the temporary primary liner was insufficient to accommodate the tolerances of the permanent liner that was to be installed inside the temporary liner. These locations are referred to as “tights”. The “Tights Removal Program” was designed to collect high resolution point clouds of the shaft, using stringent survey control, that could be compared to the design profile to generate a heat map of locations for removal of up to 75 mm of steel-fiber-reinforced, 70 MPa concrete liner. This work was all on critical path, which made it valuable to save time on the schedule. Because concrete removal was a time-intensive task, it was essential to locate and remove only the concrete that would encroach on the planned permanent liner, while attempting to maximize the amount of cutting time. Removal was carried by a road header attached to a Brokk(R) 160, a small multi-attachment demolition machine."

Jan 1, 2019

By J. Malone, D. Loth, J. Palmer

WMC Resources' Kalgoorlie Nickel Smelter was commissioned in 1972 at a design capacity of 30,000 tpa of contained Nickel in matte. A series of upgrades and progressive improvements have resulted in a design capacity increase to 110,000 tpa of contained Nickel in matte. The smelter sources nickel-in-concentrate from three Mine / Concentrators and supplies nickel-in-matte to WMC's Nickel Refinery and export customers. The Flash Furnace was last rebuilt in 1999, and is over halfway through the 10-year campaign target. The many modifications over the previous campaigns, including the Integrated Flash Furnace, are reviewed. Recent operation of the smelter and the development of the process during the current campaign are detailed herein. An overview of key interfaces with the Nickel Business Unit Concentrators and Refinery operations is provided.

Jan 1, 2005

By Lorant B. Geller

Sixteen miners died tragically at the Paymaster gold mine at Timmins, Ontario in February, 1945, when a badly corroded hoist rope broke. The investigation of the Royal Commission that followed arrived at a number of recommendations (Investigations, 1947) aimed at avoiding future disasters of this kind. One consequence was the development, and legislated use in Canada, several decades ago, of powerful electromagnetic (EM) instruments for the nondestructive testing of mine shaft wire ropes. The authors have been involved for many years in the design, production, and testing of EM instruments (Geller and Udd, 1990 and 1992, Geller and Kitzinger, 1991, Geller et al., 1993). Since the mid-1990s particular attention was paid to the design and operational results obtained from the computer- controlled portable MagnographJ II wire rope tester (Geller et al., 1995 and 1998). In the present article the authors summarize further hardware- and software-related developments of this instrument. Further, an account is given of the results obtained from the most recent design known as the PermaScanJ testing system. This is also a computerized dual-function system. In it, however, the sensor head is designed primarily, if not solely, for permanent installation and for remotely controlled operation. This represents a basic departure from traditional designs, which were intended for ad hoc temporary installations. The remotecontrolled instrument described in this paper has now been in operational use for more than 4 years.

May 1, 2003

By K. Ogawa, T. Yokoyama

Hydraulic fracturing technique, an applied technique to cause tensile fractures to rock by injecting water pressure to a certain closed section of the borehole, is a measurement method of in-situ rock stress. This technique has the highest track record for techniques used in sub 1000 meter. A feature of this technique is comparatively simple and easy for in-situ stress measurement, because the measurement is applicable when a drilled borehole is available. The predominant advantage of this method is that elastic constants such as Young’s modulus and Poisson’s ratio are not required for determining the value and direction of initial stress. The factors to determine the stress state are the water pressures of re-opening and shut-in of fractures around the borehole wall and its directions. With conventional methods, however, the accuracy of the derived stress states from the observation equations was often adversely affected by the lack of consideration of the remaining water pressure in fractures and insufficient stiffness of the pressurization system. We have developed a new hydraulic fracturing system based on a new test method concept overcoming these defects, and applied to a 300 meter deep borehole in granite. The most important improvement of the new system is an employment of a syringe pump which enables an accurate flow control of fluid with less than 1ml/min in the pressure of 30MPa. Therefore the new test system has a quick response for pressurising in the interval zone, and the measured data was confirmed extremely accurate.

Jan 1, 2015

By Patrick S. Hudd

Traditionally in hard rock mining, large diameter raise boring was thought of as 3.04 metre or 3.66 metre diameter holes 300 metres deep. Mine and ventilation engineers were challenged to design systems either incorporating such holes, or slashing and modifying to suit. Now, 5.49 metre diameter holes up to 1,000 metres deep are being excavated. The ability to pilot and ream such holes not only creates new options for mine engineers in mine ventilation system design, but also creates new opportunities in mine access. By combining holes of this diameter with the ability to accurately drill long pilot holes within the diameter of the pilot hole through the entire length of the hole, borehole hoisting systems are now fully capable of being main production or service accesses for mines. This paper will review the present day capabilities of large diameter raise boring, potential applications for such excavations and some considerations for companies contemplating using large diameter raise boring in their operations

Oct 1, 2010

By Richard Howie

Avian Diversity ?? Pre-mining ?? 110 - 125 species would have occurred ?? Dominated by forest species ?? Wetland productivity unknown ?? Post mining ?? 192 documented ?? Forested species in reduced numbers ?? Increase in wetland species ?? Increase in open country/grassland species

May 1, 2008