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By Paul D. Merica

This year of 1926 marks the 40th. anniversary of nickel mining in Canada. Although the first nickel mine of the Sudbury basin was discovered in 1883, it was not until 1886 that the Canadian Copper Company was organized and actually began to mine copper-nickel ore from the Lady McDonald, Stobie and Evans mines. The intervening years have witnessed some exceedingly interesting nickel history, particularly interesting and gratifying as well to Canadians. Forty years ago, at the inception of Canadian nickel mining, the world's consumption of that metal was about 1000 tons per annum and this was supplied largely from New Caledonia ores refined in France. This nickel was used principally for the production of nickel-silver, coinage alloys, and for nickel-plating. No processes were then known for refining the Sudbury ores nor for the separation of copper from nickel. Consequently, the pioneers in Canadian nickel mining faced the double problem of finding a method of treating their ores, and of finding a market for the nickel when and if they could extract it.

Jan 1, 1926

By P. T. O'Kane

The PLATSOL® process, initially developed for the treatment of the NorthMet Cu/Ni/PGM concentrate, has seen over the recent years its applicability extended to include numerous other Cu/Ni concentrates of the same type, as well as other precious metals-containing feedstocks. However, several concentrates were found refractory to the typical PLATSOL® conditions, more particularly so the platinum. Attempts to extend those conditions, such as higher temperatures (250°C), longer retention time, increased oxidation conditions, higher chloride additions, were not successful. Detailed mineralogical investigation of those PLATSOL® leach residues indicated the main refractory mineral to be cooperite (PtS). Further metallurgical investigations showed that a thermal pre-treatment of the concentrate effectively unlocked the refractory platinum minerals for the subsequent leach. Temperatures between 400 and 750°C were tested, with the optimum being found around 650°C. The kinetics of the pre-treatment process were fast, and one hour at temperature proved sufficient. Under those conditions, PLATSOL® extractions were re-established around 95% for both platinum and palladium. From a mineralogical examination of the calcine, it was shown that the effect of the pre-treatment was to transform the cooperite and other refractory sulphides into metallic platinum and alloys, amenable to the PLATSOL®. The implications of the pre¬treatment step for the processing of PGM concentrates arc briefly discussed.

Jan 1, 2004

By Shek N. Lau, Nicola Samman

"Enclosed gear cases on board heavy mining equipment have traditionally been lubricated with regular heavy duty gear oils. However, equipment manufacturers, have recommended the use of an ISO-1000 gear oil for this application to ensure adequate lubricant film strength, especially at the higher end of the working temperature range. The majority of these ISO-1000 gear oils are based either on residual/asphaltic oil or synthetics, primarily higher viscosity polyalphaolefins. Although the performance of these lubricants has been satisfactory, they suffered other shortcomings that equipment users have lived with over the years.The major requirement at the user’s mine was to provide lubrication for the shovel Hoist gear case. Within such a gear case design, the gears and the roller bearings, that have different lubrication requirements, are lubricated with the same lubricant. Several lubricants were used, light gear oils as well as the recommended ISO-1000 heavy gear oils. On the one hand, the lighter oils performed adequately for the lubrication of the bearings that formed part of the enclosed gear system. These lighter oils did not perform as well for the lubrication of the gears due to their lower viscosities, resulting in shorter gear servicelives.On the other hand, the ISO-1000 gear oils performed well for the lubrication of the gears, but were too viscous to creep into the bearing elements to lubricate them adequately, especially during the cold northern Canadian winters. This resulted in catastrophic bearing failures and secondary damages to the gears.The challenge, then, was to formulate a lubricant which met the 1000 cSt at 40°C viscosity requirement as stipulated by the equipment manufacturer, while satisfactorily lubricating the bearings at the full working temperature range. This was achieved by the development of a semi-fluid grease lubricant, which has proven in field trials to give adequate performance in this application for the lubrication of both the bearings and gears down to -40°C.This product met the equipment manufacturer’s performance criteria and resolved, to a large extent, leakage of the lubricant through seals experienced with the use of conventional and synthetic gear oils.Although the main performance criteria of the fluid was its capability to lubricate the “Hoist” gear case, it was also used during the field trial in other gear cases on board the shovel to test its full capabilities.This unusual alternative lubricant was field tested and evaluated for more than two years. Based on this assessment, the product was reformulated to improve its fluidity, slumpability and the settling of debris/wear metals to the bottom of the gear cases. This reformulated softer grade, a semi-fluid grease, has been performing satisfactorily for more than eight months and is still undergoing longer term assessment."

Jan 1, 1996

By M. Pearson, J. Irvine, L. Mercer, P. Lauzon

Severe service ball valve performance has a direct impact on the mechanical availability of high pressure oxidation and leach plants. The primary function of these valves is to isolate the autoclave for maintenance. Valve failure has historically contributed significantly to the maintenance downtime of these process plants. An understanding of the root causes of valve failures is the first step in increasing the reliability of the severe service ball valves. A rigorous failure analysis practice has been developed by Hatch for investigating refractory failures in furnaces and kilns based on Kepner-Tregoe methodology. The method has also been modified for valve failure analysis. From a root-cause failure tree analysis of each of the valve components, a list of all potential valve failure mechanisms was developed for ranking and evaluation, along with recommendations for further valve development. The purpose of this paper is to present the reader with the modified Kepner-Tregoe method and examples of this analysis.

Jan 1, 2004

By E. Fritz

This paper reviews the history, developments and 10 milestones of the oxygen steelmaking processes, with a special focus on conventional autothermic converters, high-speed converters with a blowing rate up to 5 m3n/t min and allothermic converters with coal addition, post combustion and the possibility to increase the scrap rate up to 50%. Related operating results are introduced. A new process route, which is based on hot metal and chromium ore, is outlined. The cost advantage for the production of 304 stainless steel grade is higher than 100 USS/t. The synthesis of EAF and oxygen converter steelmaking, a comparison of decarburization rates, refining combustion burners for optimized oxygen-management in EAF and an example for a large advanced EAF are outlined. Possibilities of flexible steelmaking and the growth and outlook of worldwide oxygen steelmaking are described.

Jan 1, 2004

By R. Boom

Corus Umuiden, formerly Hoogovens, was the first steel plant in Europe after Voest to introduce oxygen steelmaking. In the decision-making process contacts with Dofasco in Canada about the production of formability steel grades were crucial. In developing oxygen (LD-) steelmaking high liquid steel output rates had to be combined with accurate process control. For ingot casting static models with input control and sampling during interrupted blowing were sufficient to deliver liquid steel within the required carbon, phosphorus, sulphur and temperature windows. Computers were introduced to perform the complicated charge calculations. Continuous casting called for strict control of composition and temperature at process end point and made predictable timing crucial. Dynamic control was introduced based upon sub lance measurements and waste gas analysis. Reliable disposable measurement sensors were developed in a concerted international action. Dissolved oxygen at blow end deteriorated the quality of low carbon aluminium killed steel grades. Blowing gases through the converter bottom improved process kinetics, resulting in lower carbon-oxygen products, yield increase and better phosphorus removal and generated new families of hybrid blowing processes. Introduction of secondary metallurgy facilities such as argon stirring stations, vacuum degassers and ladle furnaces relieved the demands for strict BOF end point control. Desulphurisation of hot metal became standard practice. In regions with scrap shortage hot metal desiliconisation followed by dephosphorisation, was introduced in the blast furnace cast house and hot metal transfer ladles. Later redundant converter vessels were used for pre-treatment, resulting in a two-stage process. The fundamentals of oxygen steelmaking are described and a vision on the future is presented.

Jan 1, 2004

By G. J. Ackland, K. Saksl, F. Brunke, M. Kohnke, B. Tegner, C. Siemers

The application of titanium alloys is limited to 550°C due to their poor oxidation resistance. It is known that the addition of niobium decelerates the oxidation of titanium alloys whereas elements like vanadium do not improve titanium’s oxidation resistance. The underlying mechanisms are not yet well understood. In the present study, different binary titanium-niobium and titanium-vanadium alloys as well as commercially pure titanium were investigated. Oxidation experiments were carried out at 800°C up to 288 hours followed by metallographic analyses to study the oxide layer morphology as well as the microstructure at the interface. Energy-dispersive X-ray spectroscopy mappings were used to identify possible changes in the distribution of the alloying elements. In addition, micro-focused hard X-ray experiments were performed to layer-wise analyse the phase composition in selected samples. As expected, the niobium containing alloys show a better oxidation performance compared to commercially pure titanium and the titanium-vanadium alloys. The oxide layer consisted of TiO2 and Ti2O3. Depending of the niobium content, a niobium-rich layer developed below the metal-oxide-interface minimising oxygen diffusion into the titanium matrix. Based on these results, the minimal niobium content needed for improved oxidation resistance was identified so that alloys of technical relevance can now be developed.

Jan 1, 2014

By D. A. Pirttinen

The promotion of improved coal quality for thermal generation can benefit our national economy. The construction of electric generating facilities in Canada is expanding at a rapid rate to satisfy the demands of a rising population and new uses for electrical energy. With remaining economic water power resources in the process of development, generation from thermal sources continues to grow. The increase in thermal capability has been somewhat arrested by a de-pressed economy, widening of inter-provincial and state transmission networks and decisions to exploit certain water resources before high capital investment is further in-creased by rising construction costs. The introduction of extra high volt-age transmission lines will further delay thermal generation planning, but in due course, when the effects of restrictive factors have been dissipated, steam-electric generation from fossil fuels will rise to considerable proportions. In time, nuclear sources will contribute a growing share to thermal power, but, it is doubtful if nuclear participation will ever displace conventional fuels for steam rising, unless it can be adapted to operate efficiently for variable outputs in peaking service. It appears certain that fossil fueled

Jan 1, 1961

By S. U. Baltuch, E. G. Baltuch

"Ventilation in process buildings is key to proper mill function. Correctly engineered systems to evacuate surplus thermal energy from process areas allow optimized rates of air change, thus assuring the good functioning for the lifecycle of the process while demonstrating conformity with occupational hygiene standards. Computational fluid dynamic simulations, coupled with traditional calculations and physical modeling, can demonstrate to end users and assist engineers in the optimization of mill ventilation, reducing total installation costs while assuring that the proper solution is in place for the complete lifecycle of the process equipment. Results have been fully implemented on a number of steel mill and aluminium smelter applications and we continue to study, optimize, and innovate as new tools become available to provide the best possible engineered solutions for particular applications. INTRODUCTIONThe objective of this research project is the development and implementation of modern approaches and computational fluid dynamics (CFD) simulation in the engineering of green ventilation of hot process buildings. This will assure the predictive performance and improve the quality and ease of construction of industrial gravity ventilation equipment, along with the adjunct hot process buildings, while lowering the overall project costs and time to completion.In order for a hot process building, such as a steel mill, to properly function, heat must be extracted from within. This is accomplished by having air inlets at the bottom of the building and outlets at its apex. The reason for this is to maximize the potential chimney effect. When using stack (buoyancy) effect ventilation, the process heat becomes the driver. Therefore, increasing this distance (height) improves the ability of the heated airstream to utilize basic gravity for acceleration of the heat/air flow, allowing a regular number of air changes per hour while ensuring that the process environment remains weather resistant under normal operating conditions.This process has been understood since the time of King Charles I of England, who decreed in 1600 that buildings should have 10 foot ceilings and that windows should be made taller rather than wider to allow better smoke extraction.Figure 1 is a painting of the Bethlehem Steel Works in the 1860s, where the concept of air inlets and penthouses on the roofs for air outlet was already being put into practice. Figure 2 is an early photograph of the Pittsburgh Steel Works."

Jan 1, 2012

By Quenton Johnson, W. A. Gough, David Carr

"This paper describes the application of the BrainWave Model Predictive Controller (MPC) and Advanced Control Expert (ACE) Advanced Supervisory Control System on the SAG Mill, Ball Mill, and Rougher Flotation cells for a new gold processing line at the Oceana Gold - Haile Gold mine in Kershaw, South Carolina. For this project, ANDRITZ supplied the control system design and programming, operator-training simulator and advanced control. The advanced control was tested against the IDEAS™ dynamic simulator, and commissioned during the startup of the processing plant to help achieve target production as quickly as possible. Operators were able to run the equipment in a consistent and optimized manner from an early stage of the plant operation, increasing efficiency and profitability. MPC is able to reduce process variability beyond the best performance that can be obtained with conventional Proportional Integral Derivative (PID) control methods. MPC is able to optimize the control of processes that exhibit an integrating type response in combination with transport delays or variable interaction, which are characteristic of many gold processes including SAG mill weight control and Flotation cell froth level control. The experience and benefits of applying MPC during the startup of a new gold processing plant are presented in this paper.INTRODUCTION Mineral processing operations present many challenges for automatic process control due to variations in unmeasured ore properties, material transport delays, and non-linear response characteristics. Advanced process control technologies such as expert systems and multi-variable model predictive controllers are often used to improve the control of these processes to increase productivity and recovery efficiency. Typically these systems are applied after the mine has been in operation for a period of time. For this project, a complete dynamic process simulator was developed using the IDEAS platform for the purpose of training operators before the plant was constructed. Operators were able to become familiar with the process and the control system in order to become proficient in the use of the controls before the plant was ready to start. They were able to practice abnormal condition management including startup and shutdown of the process using the simulator and develop complete Standard Operating Procedures (SOPs) for these situations. The simulator was also used to test the control system functionality and operator Human Machine Interface (HMI) configuration to reduce errors and improve the performance of the control system during plant start-up."

Jan 1, 2017

By M. Kozlowski, I. Candy, S. Kashani-Nejad

The production of ferronickel and matte from nickel laterite ores is dominated by the Rotary Kiln, Electric Furnace (RKEF) process. Over time, major improvements have been made to kiln operation. In particular, kilns are now required to perform substantial amounts of reduction of the metallic oxides, thereby reducing the load on the electric furnace and substituting less expensive fossil fuel for electrical energy. To the basic refractory lined cylinder have been added: internal features such as dams and lifters, aimed at changing residence times in different sections of the kiln and enhancing gas/solids interaction, on-board fans to introduce tertiary air and on-board scoop mechanisms to allow reductant coal additions to be made at advantageous locations along the kiln. Many of these advances in design have been made on a trial and error basis and by 'borrowing' technology from related kiln processes, supplemented by proprietary modeling to various levels of sophistication. This paper presents a conceptual review of modeling components for the development of a computational model for granular material flow, combustion and heat and mass transfer in a nickel laterite kiln. These components include: granular material flow and segregation models for the simulation of bed motion, heat transfer models that simulate heat transfer by turbulent diffusion and radiation and the distribution of this thermal energy within the bed, and fluid flow models for the prediction of combustion aerodynamics.

Jan 1, 2005

By R. B. Hyde

"Severe drilling conditions and difficult mud problems are briefly out-lined as the major cost items in all production operations. The chief problems discussed are abnormal pressures, high temperature, trouble-some shales, and low rates of penetration. These problems have been eliminated or greatly reduced in many areas by• the proper application of recently developed drilling mud products and techniques. These severe problems and their solutions are discussed generally: the application of high-density weighting materials to overcome abnormal pressures; surfactant muds with sodium polyacrylate as a solution for deep and high-temperature drilling; shale control muds and new dispersants for severe shale problems; and low-solids emulsions and •extreme-pressure lubricants for greatly improved rates of penetration."

Jan 1, 1959

By Brad Hewitt, Jeff Belke

"Murrin Murrin Operations has not had a successful beginning. Numerous reliability and operability issues many of which are the result of design decisions have been addressed through mechanical and operational changes and the CCD circuit is no exception. Four design aspects of the CCD circuit that have caused and continue to cause operational problems are:1. the inclusion of solution neutralisation gypsum in the CCD circuit feed which was designed solely for HPAL residue without proper investigation of its impact on the achievable underflow density and resulting wash efficiency;2. the decision to construct the thickener base from thickened solids;3. the lack of redundancy in the overflow, underflow and tailings pipe work; and4. the lack of thickener operational flexibility in the central rake-lift and feedwell dilution system.In November 2002, the lack of operational flexibility in the rake-lift and the feedwell dilution system through mechanical modification as follows:•, CCD1 has a modified rake mechanism that now allows central vertical lift of 600 mm;•, CCD1 has forced dilution using the Outokumpu Turbodil® technology and replacing the E-Duc® technology of Eimco;The decision to install, the installation and the results of the CCD1 rake-lift mechanism and feedwell dilution system are discussed in this paper. The installation was justified on improved operational robustness and an increase in the in the underflow density of 1 per cent (per cent w/w). At approximately the same time process modifications in the solution neutralisation circuit were implemented and these changes altered the rheology of the slurry reporting to CCD1. Since the modifications to CCD1 and the solution neutralisation circuit, the CCD circuit has averaged a 2 per cent improvement in the circuit underflow density.The CCD1 modification was completed on time and mechanically has performed well. From a risk point of view, the central rake-lift and Turbodil®dilution system add a degree of freedom and robustness to CCD1 operation that has extended the range of operational confidence. In this respect, the modification has been a success and is complementary solution neutralisation improvements."

Jan 1, 2005

By A. Ignatieff

"THE WORLD'S coal resources represent the largest component of non-renewable energy resources. Coal is now regaining Its position following a temporary decline, particularly in North America during a period of about a quarter of a century. This period provided the opportunity to improve both surface and underground mechanization, thereby increasing the productivity and improving conditions for humans in the mines. Similarly, in preparation, improved cleaning of coal from various impurities including sulphur was achieved, to meet the more demanding requirements for coking coal. Progress was also made in combustion, particularly related to the reduction of pollution. Canada participated in most of these developments, despite the country's strong commitment of the use of hydrocarbons during this period. _Bearing in mind the vastness of this land (3.85 million sq. miles) by comparison with countries like U.S.A., U.S.S.R., and China, Canada's coal resources estimated to date are not large and they are scattered. The original evaluation of 1913 estimated the ""reserves"" from seams over one foot in thickness and a limiting depth of 4,000 ft at 1.2 trillion metric tons. D:. ~.R. MacKay, in his evaluation for the 1946 Royal Commission on the coal industry, known as the Carroll Commission, reduced the ""reserves"" to 99 billion short tons. The increased knowledge now available would indicate that the 1913 estimated was too liberal and the 1946 estimate too conservative but both were closer to a resource than to a reserve designation. Some adjustments of Dr. MacKay's estimates were made in 1970 by B.A. Latour of the Geological Survey of Canada and L.P. Chrismas of Energy, Mines and Resources Canada (EMR). In the last decade the Alberta Energy Resources Conservation Board has developed its own methods of evaluating coal resources and reserves. A methodical approach of exploration and evaluation was carried out by Saskatchewan jointly with the federal government of the lignite resources of Southern Saskatchewan. A similar joint program is in progress in Nova Scotia. Meanwhile, the industry itself carried on an extensive exploration program on the outcrops of promising projects in the Inner Foothills belt of Alberta and British Columbia in preparation for surface mining on a very large scale, with some development of hydraulic mines. All these activities have been reflected in the increase of the country's resources and reserves, which now fortunately are separately defined. In 1979 EMR issued Report E.R. 79/9(1>; the data were developed in 1978 and provided to the World Energy Conference Organization<2>. In 1980 the World Coal Study (Wocol), an international group that included Canada carried out a study which updated the W.E.C. data, indicating some reduction of the 1978 figures; quantities were reported in million metric tons of coal equivalent (C.E.)*(Jl."

Jan 1, 1985

By Y. Rama Murthy, Amit Ranjan, Pankaj Satija, Sunil K. Tripathy

"Chromite ore is one of the essential raw materials for ferroalloy and steel industry. Boula-Nuasahi belt of Sukinda region, Odisha, is the only resource of chrome ore in India. The Indian deposits are typically characterized as ferruginous and siliceous type ores. Chrome ore is generally mined by open cast mechanized mining method in these areas. The run-off-mine (ROM) ore from the various mines is sent to beneficiation plant via stack yard for further up gradation. The chrome ore beneficiation plant (COB) has two major circuits: comminution (feed preparation) circuit and beneficiation circuit. In the comminution circuit, the ore is reduced to <1 mm size ( for complete liberation of chromite) from -220 mm size in stage wise crushing (primary and secondary crusher) followed by screening and single stage grinding in a ball mill. Fraction having size <1 mm is further upgraded in the beneficiation circuit to produce three different concentrates having specific chemical composition and Cr: Fe ratio. The beneficiation plant is a complex circuit comprising of combination of unit operations (spiral concentrator, Floatex density separator, hydrocyclone, wet shaking tables). In the recent years the overall performance efficiency (grade and recovery) of the beneficiation circuit got affected with numerous changes in the run-off-mine ore quality (physical and chemical), mineralogical composition, etc.In this article, attempts made for improving the performance of chrome ore beneficiation circuit is discussed. The approach adopted and practical problems encountered while the process were also highlighted. The results of the trials has shown an improvement in the performance of the cyclone (d50 : 56 µm – 40 µm) and chromite losses into tailing to <12%.INTRODUCTIONChromite has a wide range of application, from refractories to metallurgical industries, and from chemical to non-ferrous alloy industries. Chromium ore (Fe2+, Mg) [Cr, Al, Fe3+]2O4) occurs exclusively in rocks formed by the intrusion and solidification of molten lava or magma which is very rich in the heavy, iron containing minerals such as pyroxene and olivine. With the richness of silica and iron, the chrome ores are broadly classified as siliceous type and ferruginous type. Pure chromite with composition FeCr2O4 is rare because magnesium usually substitutes for ferrous ion and aluminum and ferrous ion substitutes for chromium. Generally the associated gangue minerals are talc, quartz, hematite, goethite, limonite, gabro, serpentine, anorthosite, dunite, pyroxinite, etc. Around 96% of the chromite ore production is consumed for metallurgical applications of which 94% is converted into different grades of ferrochrome i.e., high carbon ferrochrome and charge chrome as shown in Figure 1. Stainless steel being the leading consumer of ferrochrome, any change in the dynamics of the stainless steel industry impacts overall chrome ore demands significantly."

Jan 1, 2016

By C. Turek, R. Henderson

Mine planning is the foundation of value for a mining company. Good mine planning requires solid understanding of the ore body, rigorous standards and processes, robust and useful information technology and skilled people. Life of mine planning is key to identifying strategic direction for any mine and short range mine planning is key to delivering forecast and budget expectations. Mine planning at Kinross has been identified as a critical success factor and initiatives are being prepared to improve the quality of our plans and to build bench strength in our teams. The Kinross Way for Mine Planning (KWMP) has been developed and implemented to establish the standards to ensure a strong business foundation. This paper briefly describes the process used to develop the KWMP and presents a selection of mine planning best practice initiatives at Kinross mines.

Jan 1, 2011

By S. Mostaghel, Fariba Azgomi, Steven Goodman, M. Oliazadeh

"It is known that copper loss to the slag phase can be in the forms of chemical dissolution and mechanical entrainment. The contribution of each mechanism to the total Cu-loss depends on different parameters and may vary significantly. To reduce emissions to the atmosphere and to shorten the converting cycle, most industrial processes are aiming at production of high matte grades. Increased oxygen-to-sulfur potential, required by these processes, results in a highly oxidized slag, which in turn leads to an increased concentration of the chemically dissolved copper in the slag phase. Hence, slag cleaning processes are becoming increasingly important for economic viability of the smelting operations. Hydrometallurgical, pyrometallurgical, and mineral processing routes have been used for copper recovery from slag. The current article reviews a trade-off study evaluating two of the commonly used methods (namely flotation and electric slag cleaning furnace) by comparing the technical pros and cons, operability/maintenance requirements, and capital/operating costs of the operations.INTRODUCTIONLarge volumes of smelter and converter slags are produced by copper smelters around the world. It is estimated that for production of each ton of metal 2.2 tons of slag is produced (Gorai, Jana, & Premchand, 2003). Considering the current pressure on the mining and metals industry for “zero-waste, sustainable and environmentally friendly” extraction of metals, it is absolutely essential for metal producers to improve their efficiencies in order to remain competitive. To meet these objectives, almost all metal producers, from steelmaking plants, ferroalloys, base and precious metals producers, are trying to reduce their metal losses to the slag phase. In particular, copper producers are aiming to produce higher matte grades in their smelting furnaces to reduce the converting time and improve their overall throughput. Copper smelters need to minimize their copper/precious metal losses to the slag phase before final landfilling/use of slag. The current article, therefore, briefly reviews the copper loss to the slag phase, methods of metal recovery from the slag and then presents a trade-off study conducted for a green field flash smelter of the sulfide concentrates. A comparison was made between two of the major process routes for metal recovery from slag, namely slag cleaning furnace and flotation."

Jan 1, 2016

By G. P. Kundargi

India is one of the fastest growing economies in the world. The role of the Iron & Steel industry is very important for the development of the country. Iron and steel are among the most important components required for the infrastructure development of the country. This is one of the fastest growing sectors. The demand drivers for the Indian Iron & Steel industry are increase in the activities of the manufacturing industry and infrastructure development. Indian Iron & Steel industry with its strong forward and backward linkages contributes significantly to overall growth and development of the economy. The industry today directly contributes 2% of India?s Gross Domestic Product and its weightage in the official Index of Industrial Production (IIP) is 6.2%. Manganese is a main ingredient for production of steel. Almost 90% manganese is being utilized by the steel industry worldwide. Globally, there is no substitute for manganese as on date. There is huge gap between demand and production of manganese ore in the country. To meet this demand gap and to support for growth of national economy, MOIL Limited (formerly Manganese Ore India Limited), a Government Enterprises, producing annually around 1.1 million tonnes (mt) of manganese ore and value added products, has geared up with various infrastructural activities to increase the present production capacity of 1.1?1.5 mt in 2016?2017 and 2.2 mt in 2020?2021. The paper deals with the technological improvements and infrastructural development activities of MOIL; this will help MOIL to become the market leader in manganese ore production globally in the coming years.

Aug 1, 2013

By Rick J. Chalaturnyk

In Alberta, oil sands bitumen is utilized for synthetic crude oil production by surface mining, bitumen extraction followed by primary (coking) and secondary (catalytic hydrotreating) upgrading processes, or by catalytic hydrocracking and hydrotreating replacing the primary and secondary upgrading processes. Oil sands tailings, composed of water, sands, silt, clay and residual bitumen, is produced as a byproduct of the bitumen extraction process. Several processes have been proposed for the treatment of oil sands tailings, resulting in different recovered water characteristics, consolidation rates and consolidated solid characteristics, which may have effects on the performance of the overall plant operations. A process for the same purpose has been developed by treating the oil sands tailings with CaO lime and CO2 and thickening it using a suitable thickener. In this process a release water of acceptable properties is recovered in a short retention time, which makes it possible to recycle the recovered water, probably after a reconditioning treatment, as warm as possible to improve the thermal efficiency of the extraction process. The paper presents the theory and laboratory results for the CaO and CO2 thickening of low temperature flotation tailings. The water release rates, segregation potential of the thickened underflow and chemistry of the release water are shown and discussed. It is suggested that in using the proposed process, the thickened tailings underflow can be disposed for further consolidation, or combined with the coarse tailings to produce Blended Composite Tailings, corresponding to the Composite Tailings process in the existing hot water extraction plants.

May 1, 2002

By L. Bichler, A. Siebert-Timmer

In this research, novel YSZ ceramics doped with 5 mol% Nd2O3 were manufactured via Spark Plasma Sintering (SPS) process. The sintered Nd2O3-YSZ ceramics were subjected to a static supercritical water environment at a temperature and pressure of 400 °C and 31 MPa, respectively. The weight loss and microstructure development of the sintered ceramic before and after exposure to supercritical water was studied. The results suggested that Nd2O3 addition significantly improved the degradation resistance of the YSZ ceramics. This was attributed to the improved phase stability of the 5 mol% Nd2O3-YSZ ceramics, since X-ray Diffraction (XRD) studies showed that the cubic stabilized matrix in these ceramics was retained after exposure to supercritical water. In comparison, pure YSZ ceramics exhibited a rapid degradation behavior as well as a phase change.

Jan 1, 2014