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By Barbara A. Filas

The IFC goal is to promote private sector investment in developing countries which will reduce poverty and improve people?s lives. The developing country goal is to promote health, education and employment opportunities that improve their economies and their standard of living. The mining company goal is to Promote successful ?triple bottom line? mining projects that will grow shareholder equity

May 1, 2002

By P. J. Oakley, W. M. Thomas, S. W. Kallee, D. G. Staines

A Friction stir welding (FSW) is now extensively used in aluminium industries for joining and material processing applications. The (FSW) technology has gained increasing interest and importance since its invention at TWI almost 15 years ago. The basic principle, recent applications and the continuing development of the FSW technology are described. The paper will introduce some of the variants of FSW, such as Dual-rotation, Twin-stir(TM), and the Stir-lock(TM) technique.

Jan 1, 2006

By Vlad Ruzicka

"Uranium deposits in the Rabbit Lake-Collins Bay area are associated with the sub-Athabasca unconformity which separates crystalline Archean or Aphebian basement rocks from Helikian clastic sedimentary rocks of the Athabasca Group. The basement rocks are a part of Wollaston lithostructural domain.Most of the high grade deposits, such as Collins Bay ‘A’ and 'B' Zones and Eagle Point are associated with altered rocks of the basal unit of the Wollaston Group. Some deposits, such as Raven and Horseshoe are confined to the uppermost unit of this Group. The Rabbit Lake deposit occurs in the middle, meta-arkose unit of the sequence. Locations of some deposits (Rabbit Lake, Collins Bay ‘A’ and 'B' Zones) are also controlled by thrust faults, such as Rabbit Lake Fault and Collins Bay Fault.The deposits contain either monometallic (uranium) mineralization (Rabbit Lake, Raven, Horseshoe) or polymetallic (mainly uranium-nickel) assemblages (Collins Bay “A’ and 'B' Zones).IntroductionThe Athabasca Basin region, a part of the Churchill Geological Province of the Canadian Shield, is composed of Archean and Aphebian crystalline basement and younger, Helikian, unmetamorphosed supracrustal rocks. The Rabbit Lake-Collins Bay area is situated at the eastern margin of the Athabasca Basin region, which hosts a substantial proportion of Canadian uranium resources.The crystalline basement complex was subdivided by Lewry and Sibbald (1979) into lithostructural domains and these domains were grouped into major crustal units designated, from northwest to southeast, as Western Craton, Cree Lake Mobile Zone, consisting of Wollaston, Mudjatic and Virgin River domains, and Rottenstone Complex (Fig. 1)."

Jan 1, 1986

By K. S. Coley, M. A. Rhamdhani, G. A. Brooks

Interfacial phenomena in high temperature reactions such as between iron alloy and slag is well documented but not fully understood. It is believed that a gradient of oxygen concentration plays an important role to the occurrence of such phenomena. This article describes the results from the continuation of the study of interfacial phenomena between Fe-Al alloy droplets and CaO-SiO2-Al2O3 slag. Materials characterization techniques involving microscopic observations, depth profiling, bulk, point analysis and were carried out. The roles of oxygen as well as other factors that contribute to the interfacial phenomena were evaluated. The results and their implications to steelmaking will be discussed.

Jan 1, 2004

By M. Connell, S. Bedrossian

Alkali cracking followed by chloride-based leaching is one of the prominent methods for rare earth element processing. Regeneration of the leach lixiviant, namely hydrochloric acid, is a critical operation in the process. A number of different process routes are available for recovery of hydrochloric acid from chloride solutions. The objective of this paper is to discuss various recovery routes and analyze the impact of several input variables on the variable operating cost.

Jan 1, 2014

By S. C. Cohen, A. F. Mikkelsen

"This paper describes the improvements made to the operation of a liquid phase, 300°C, heat transfer system in the paste plant of an aluminum smelter. These improvements were achieved by replacing the original heat transfer fluid, a synthetic aromatic, with a new technology, petroleum-based product. This new fluid, Calflo HTF, provided better thermal stability, with lower toxicity, and improved plant working conditions.The procedures for fluid selection, changeout and performance monitoring are described along with a summary of control analysis over the last three years."

Jan 1, 1993

By Marke Wong

? Vietnam?s economy is growing so fast that gross domestic product (GDP) growth remained above 8% in 2005 and exports are rising steadily at 25% per year. ? Demand for electricity is expected to increase 18% per year through 2010 requiring an additional estimated 7,547 MW before 2010 ? Domestic coal demand is expected to be over 45 Mt by 2010. ? The Quang Ninhcoal deposits are estimated at 6.5-7 billion tons (350m) Vietnam News Agency. Saturday, May, 6, 2006. ? National resources are now estimated at 10 billion tonnes; not including a relative new coal bed discovery estimated at 210 billion tonnesin the Red River Basin.

May 1, 2006

By P. M. Pearson

This paper describes the principles ()f systems engineering and their application to the various transport problems confronting the mining industry. The organization of mining operations into sub-system design problems is explained.

Jan 1, 1970

By Margarete Kalin

Mine Waste Management ?Reduction of Sulphideoxidation or inhibiting weathering of rocks Geologist - broken or ground rocks Hydrologist - sources of contaminants Mining engineer - waste sites Consulting companies - income units People - Ugly, bad, dead Ecological Engineer Landscapes which contain building blocks of an emerging ecosyste

May 1, 2013

By P. E. Weidmark

"PART 1-Published PapersAllcott, G.A., and Archibald, D.E.; ""Description of pillar behaviour at Heath Steele Mines""; Can Min Metall Bull; 74:834:80-87; 1981.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of rock Mechanics; 3:32-33; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:37-38; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:38; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses"" ; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:41; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:42; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:46; 1979.Baar, C.A.; Discussion of Theme 2: ""Tectonophysics""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:60; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3: 116; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:116-117; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:117; 1979.Baar, C.A. '; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:118-119; 1979.Baar, C.A.; Discussions (2) of Theme 4: ""Underground openings""; Proceedings 3rd Congress lntnl Soc of Rock Mechanics; 3:119; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:120-121; 1979."

Jan 1, 1982

By Qidong Xu

Abstract - The metavolcanic rocks of the Dahongshan area have been subjected to both widespread hydrothermal alteration from circulating seawater and to regional metamorphism, such that their mineralogic and chemical compositions have been changed significantly. Studies of immobile elements show that these rocks were originally tholeiitic basalts with geochemical characteristics of T-type MORB formed in a mid-ocean ridge environment. The accompanying Cu-Fe-rich VMS mineralization is in keeping with the original petrology and tectonic setting of these metavolcanic rocks. Regional alteration evident in K-Mg enrichment is related to sericitization and chloritization. Local alteration associated with Cu-Fe mineralization appears to have been accompanied by Si enrichment and Na depletion. P enrichment identifies metasomatism related to Cu-Fe reconcentration in the mineralized zone.

Jan 1, 1999

By Marek Mika

This Paper has been prepared to be presented at the 23rd World Mining Congress & Expo ? Montreal 2013. It presents the idea how to carry out the shaft sinking operation, going through highly water-bearing and very weak rock strata, giving as an example one specific shaft sinking project which is being executed for one of the Polish collieries by our Shaft Sinking Company Content 1. Introduction. 2. Hydrogeological conditions within the area of the shaft. 2.1. Hydrogeological conditions assumed at the stage of designing. 2.2. Hydrogeological conditions encountered in the course of sinking. 3. Designed shaft lining. 4. Procedures for the shaft sinking. 4.1. Designed procedures of the shaft sinking. 4.2. Procedures for preservation and strengthening of the shaft lining and the surrounding rock strata. 5. Technological guidelines for proceeding with the shaft sinking ? selection of special methods. 6. Options for mechanization of work for the selected method. 7. Conclusions.

Aug 1, 2013

By Ji Wang

Reflective in-seam wave detection has the advantages of a far detection range and wide applicability. It has been successfully used in detection of many abnormal geological structures in work-faces, such as faults and collapse columns. However, a reflective in-seam wave is a dispersion wave. It has weak energy and is always covered by the direct in-seam wave. In the past, underground seismic explorations were not able to image the opposite roadway using reflective in-seam waves. To solve this problem, we propose a new method of reflective in-seam wave imaging based on adaptive dispersion filtering. This method processes the reflective in-seam wave using a filter with the parameter of transmission distance. The degree of similarity of the filtered and the explosion signal is used to estimate the transmission distance and image the reflective objects. We test and verify this method using real underground seismic data. This research is helpful for the detection of coal mine goafs and abandoned roadways in work-faces or in front of tunneling ends.

Aug 1, 2013

By Andrew J. Freyman, Graham T. Armstrong

"In September, 1968, a survey of operating mines in the Yukon and the Northwest Territories was undertaken to determine the role of Indigenes (Indian, Metis, Eskimo) on the mines, and the attitude of mine management to these employees. The operating mines in the Territories had (at that date) a total employment of 2,002 men, of which 91 (4.5 per cent) were Indigenes. Indigenes make up 45 per cent of the Territorial population (18 per cent in the Yukon and 63 percent in the Northwest Territories). The paper documents some of the problems associated with indigenous employment in mines. A study was undertaken to determine the role of Indigenes (Indians, Metis, Eskimos) in operating mines in the Yukon and in the North-west Territories. In addition to the mines north of the 60th parallel, the experience of several other Canadian mines was examined. The general picture obtained is considered to be representative of the Canadian mining industry."

Jan 1, 1969

By Kazem Oraee

Implementing stable final pit walls in open pit mines during the open pit design phase and mine exploitation has become one of the most important concerns of mining engineers in recent years. Failure of mine walls can potentially cause loss of life, roads blocks, and damage to mining machinery, temporarily or permanently halt production at the face and in the worst case scenario, close the mine. Thus, the role of creating stable mine walls is crucial to safety and general operations of mines and any effort to optimize this process has great economic value for mine operators. This paper aims to illustrate the technical aspects of use of the successful presplit blasting method in metal open pit mines. It also shows that using this approach not only increases safety in mines through wall stabilization, but also will boost economic profits by savings in stripping ratio. In this regard, appropriate practical concepts for designing the drilling and blasting patterns and the role of selecting the correct drilling rigs are elaborated in detail through conducting a case study in Chador Malu iron ore mine in Iran.

Aug 1, 2013

By G. Q. Zhou, H. C. Liang, X. D. Zhao

"This study describes the strain behavior in vertical shaft lining (VSL) embedded in thick soil deposits and its application in assessment of concrete deterioration. The observed strain in VSL continuously decreased companied by a sinusoidal fluctuation due to the influences derived from negative skin friction (NSF) and temperature. The increase in strain increment between peak and trough at each year and compressive strain level as the servicing time continued and VSL depth increased implies that the concrete strength was attenuated, and this attenuation was significantly dependent on the existing compressive strain level in VSL. The reliability of the proposed approach was validated by Schmidt Hammer Technique (SHT) – based concrete strength, and is applicable in concrete assessment and then fracturing prediction of VLSs in thick soil deposits.Concrete strength, Field monitoring, Strain behavior, Vertical shaft liningINTRODUCTIONOver 100 VSLs in Southeastern China subjected to an unpredictable fracturing as shown in Figure1, and there are over 1,000 VSLs embedded in thick alluvium su?ering from challenges of damaging and potential fracturing (Cheng, Yang, Zhou, Li, & Hu, 1993; Zhou, Cui, Lv, Huang, & Chen, 1999; Li & Li,2005). Therefore, a reliable assessment of these VSLs is significant to the normal servicing of mine shafts and the recycle of underground space when these mine shafts were closed.The continuous increasing of NSF induced by the drainage of water–saturated deposits well interpreted such extensive fracturing phenomenon, and it is universally regarded as the governing indicator to determine the VSL stabilization (Cheng et al., 1993; Zhou et al., 1999). Based on this recognition, the fracturing prediction and VSL strengthening according to the field monitoring on hydrogeological characteristics, servicing environments, and mechanical behaviors of VSL were carried out (Zhao, Zhou, Zhong, Zhu, & Liang, 2009; Liang et al., 2009; Xie, Lv, & Wu, 2014). As known, the compressive strain level in VSL and the in–situ strength of VSL concrete were the main factors to perform such fracturing prediction. However, the existing studies in literatures were limited to the strain accumulating or releasing behaviors (Zhao, Zhou, Zhao, Kuang, & Hu, 2017), and lack of considering the VSL concrete strength and its attenuation. In this reported study, the in–situ monitoring data on the strain in typical VSLs and the VSL elevations between 2004 and 2014 were initially analyzed. Then, an observed strain behaviors–based approach was developed to quantitatively evaluate the VSL concrete deterioration."

Jan 1, 2019

By G. K. Quainoo

Investigation by researchers on the application of various thermo-mechanical process histories on 6000 series aluminum alloys have found improvements in mechanical properties of these alloys. However, natural aging, which is unavoidable in the automotive processing line, has been found to have deleterious effect on subsequent artificial aging properties in these alloys. In this study, the evolution of yield strength during natural aging modeled by Lloyd and Gupta has been adapted to investigate the effect of cold deformation on the natural aging kinetics in AA61 11 by means of tensile testing, differential scanning calorimeter (DSC) and scanning electron microscopy (SEM). Also, intermetallic particles in the alloy were extracted from the matrix and XRD performed on them to ascertain their composition and their role on the kinetics in the alloy. The results show that cold work effect on the natural aging kinetics of AA6111 is in very good agreement with the model proposed by Lloyd and Gupta. The kinetics of natural aging in AA6111 aluminum also decreases with increasing level of cold work. This is attributed to dislocations serving as sinks which consume quenched-in vacancies formed during the early stages of clustering. The phases of the intermetallic particles identified in AA6111 are those of a-A15Mn12Si7 and a-A15MnSi.

Jan 1, 2007

By D. Adiguzel

In this research, providing the sustainability of production quality was aimed for a quarry which is located in Istanbul western part of Turkey and producing concrete aggregates with different types of rock. First, research field was divided in 3 different areas in accordance with the geological differences and parameters that control their product quality, limit values of standards and effect levels were determined. Concrete aggregate conformity tests which are stated in international standards were applied on samples which were taken from these 3 different areas and physical, geometric and chemical properties of each rock type were revealed. The properties of the 3 different types of rock which were produced in the quary were determined and the binary blends were composed. Blending studies were conducted with linear programming technique. In the linear programming model, the cost of aggregate production was aimed to be minimal. The limit values that meet literature and national standards for usability of aggregates in concrete were defined as constraints in the linear programming model and evaluated with objective functions, thus the most suitable aggregate blends were composed. In conclusion, to provide the sustainability of product quality, the most appropriate product blends were composed for the research field and the usability of this model for those quarries were revealed.

Aug 1, 2013

By M. Piard

Fires and explosions are not likely to originate in clean gobs above pillar faces steadily driven through a solid panel in order to effect a complete extraction. As. to the storage which such a process implies where the market is intermittent, its cost will never equal that of abandoning large pillars in a fully developed property. Much less will that cost, thanks to the big sizes obtained, ever approach that of cleaning wet and dirty crushings robbed at great expense from small pillars exposed to many years of roof pressure. Even thick seams under bad roof may be fully extracted without the help of filling material. Fatal accidents from falls of roof owing to the great height of excavations, losses in coal, and the danger from fire, have compelled operators in South Staffordshire, England, to discontinue the stall-and-pillar system at one time supreme in the district, and to successfully adopt the following plan: A retreating' longwall is run along the top coal, as the first working; the bottom coal is taken in the same manner, after the fallen roof has become sufficiently consolidated to allow the mine to be reopened. A similar plan is suggested in this paper in order to deal with the outcropping and pitching seams found in the Kootenay measures.

Jan 1, 1930

By W. Lodge, G. Rasmussen

"The carbon-in-pulp (CIP) process has been the dominant gold recovery technology since the 1980s. During all this time carbon measurement, and control of the carbon transfer pumps has been largely manual in nature. Such manual operation inevitably limits process efficiency, potentially resulting in higher gold solution losses, and higher cost of circuit operation. Based on the authors’ experience, average plant solution loss is in the range of 0.02-0.03 ppm Au, as opposed to the general industry target of 0.01 ppm Au or less. Gekko Systems, in conjunction with Curtin University’s Gold Technology Group, has developed a carbon concentration meter, the ‘Carbon Scout’ meter. The meter automatically measures carbon concentration in all tanks, providing more frequent and more precise data. Combined with SIMCIL, a CIP circuit process model which is used to determine the optimum set points for the circuit, the meter should ensure lower gold solution losses, and more efficient operation of the carbon circuit. This paper will review they critical factors for good carbon management, the development of the meter and results from the first plant installation. Additional benefits of the Carbon Scout, including improved health and safety and the opportunity to measure other key variables in the leach/adsorption circuit from one central location will also be described.INTRODUCTION The carbon-in-pulp (CIP) process was first introduced to the gold industry in the early 1950s at the Carlton Mill in the USA (Fast, 1988), with the modern version of CIP becoming fully developed with large scale installations in South Africa in the late 1970s (Laxen, 1982). CIP quickly became the technology of choice for new operations, and for the retrofitting or upgrading of existing operations. In the 1980s the carbon-in-leach (CIL) circuit configuration became the process design of choice due mainly to its lower capital costs. With 40 years of operational experience, CIP/CIL for gold recovery is now mature a technology, whose operations and limitations are well understood. To extract further efficiencies from such technologies, by improving recoveries and/or reducing operating costs, is challenging and may require new approaches to circuit management. Gekko Systems, in association with the Gold Technology Group at Curtin University, has developed the Carbon Scout, an automated carbon measurement device. This device replaces manual measurement of carbon concentration in carbon adsorption tanks, providing more frequent and more accurate data for control of the CIP process. Data from the Carbon Scout can be used to automatically control the carbon forwarding pumps."

Jan 1, 2018