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By S Saydam

Professional engineers need to be able to apply university learning to practice. In particular, they have to take responsibility for interactions between technical systems and the complex social environments in which they operate. The most effective way of building this competency is through active experiential learning. We have been developing an advanced educational integrated simulation system to provide mining engineering students with an interactive and immersive learning experience that is not otherwise possible. This will give students an authentic experience in working with industry software packages, while also contextualising the learning in terms of the broader and longer-term impact of technical decisions. We have been piloting the system, in undergraduate courses in order to establish its effectiveness in building systems thinking competencies for mining engineering. For postgraduate students and professionals, the same tools and methods can support studies of more challenging and complex scenarios where mining engineers have to place their decisions within complex global industry contexts.

Nov 22, 2011

By Paul Pugsley

The EMSpec sensor employs the principle of measuring the complex impedance of the target steel over a range of frequencies these impedance values in turn varies with transformation fraction of the steel. A full scale implementation of the Real Time Transformation Monitoring has been installed at a quality large European steel producer to show the benefits of such a system. A total of three EMSpec sensor heads have been installed between the exit Finishing Mill and the Down Coiler on a HSM. For the successful production of Dual Phase, TRIP and TWIP steels increased control of the cooling regime is demanded; the use of surface temperature measurements alone cannot guarantee to achieve the desired mechanical properties. The EMSpec sensor, which is engineered to withstand this harsh environment, in real time directly measures the percentage transformation of the steel in the cooling area, typically in the accelerated water cooling zone. Using the information from the sensors integrated into the mill model enhances the models ability to predict the transformation profile.

Aug 17, 2017

By Alexsander Orrico Marchesi

Este trabalho foi realizado com o objetivo de identificar os motivos das trocas prematuras dos segmentos da máquina de lingotamento contínuo 1 da ArcelorMittal Tubarão e indicar propostas de engenharia para aumentar a sua confiabilidade e disponibilidade operacional . A metodologia utilizada foi a estratificação dos dados históricos, coletados no sistema informatizado de manutenção da empresa (SIM), para identificar, classificar e analisar as causas das trocas prematuras realizadas. A partir disso, baseado em conceitos de engenharia de manutenção, foram utilizados métodos de análises de falhas, como Diagrama de Pareto, Brainstorming, Diagrama de Ishikawa e Matriz Esforço x Impacto para elaboração de propostas de plano de ação modelo 5W1H visando à eliminação dos problemas.

Aug 7, 2018

By R. M. Santmyers

This paper represents one of a series of digests of foreign mining legislation that is being prepared in advance of a general report relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries . This interpretation of the mining legislation of Tunisia was prepared from a copy ( in French ) of the Mining Decree of Tunisia promulgated December 29 , 1913 , by the Resident General of France in Tunisia and effective January 1 , 1914. It is released subject to correction and amplification , if necessary , by the proper American diplomatic and consular officers , to whom it will be referred through the courtesy of the Department of State .

Mar 1, 1933

By Laurent Rus, Bakar Amara, Jean Habimana

The La Fontaine Tunnel in Montreal, Quebec is currently undergoing major structural rehabilitation work and systems upgrade work to comply with current codes, standards and best practices in fire life safety and to extend its lifespan of this 55-year-old immersed tube tunnel for at least another 40 years. The paper discusses design consideration of ongoing works that include structural analyses to evaluate repair strategies for the post-tensioned reinforced caissons, the scheme to repair two leaky joints between caissons, the design of passive fire protection that involved in situ and real scale laboratory tests, and other tunnel systems upgrades.

Jun 13, 2023

By Ali Hafiz, Aidin Golrokh, Tom Iseley, Kaz Tabrizi, Saleh Behbahani

In the USA many highway tunnels were built during the 1930s through 1960s. This indicates that these tunnels have exceeded their intended design service life. Based on the initial tunnel inventory conducted jointly by the Federal Highway Administration (FHWA) and the Federal Transit Administration (FTA), more than 526 highway tunnels have been identified in the USA. For understanding the condition of the tunnels and risks associated with deteriorating conditions, comprehensive condition assessments are necessary to mitigate risk and remediate works as required. Monitoring the condition and rate of deterioration of tunnels is vital for timely tunnel maintenance and rehabilitation to avoid sudden tunnel collapse. This session will explain the necessary steps for tunnel inspection and review some of the state of the practice information on tunnel inspection techniques.

Jun 13, 2023

By David I. Smith, Kenneth Arnold, Bryan Aweh, Vincent Falkowsk, Brian Lakin, Andy Fer

Nassau County, New York, is undertaking several projects to improve the water quality in the Western Bays of Long Island. A major step forward will be the completion of the Bay Park Conveyance Project, which will divert most treated effluent away from the Western Bays to an existing ocean outfall at the Cedar Creek Water Pollution Control Plant. The ongoing works include 3.6 miles of microtunneling, 7 miles of sliplining, 14 shafts, and a 75 MGD pump station. This paper provides an overview of the design and an update on construction progress through December 2022. The project is a collaborative effort between Nassau County, New York State Department of Environmental Conservation, the design-builder, and various consultants.

Jun 13, 2023

By Rodrigo Fina Ferreira

This paper presents a mineral liberation study on two iron ore samples from the Quadrilátero Ferrífero, in Brazil: compact itabirite of low-grade metamorphism (CI) and friable itabirite of high-grade metamorphism (FI). The quartz liberation spectrum for both samples have been obtained through QEMSCAN analyses, carried out for several comminution degrees, to compare the liberation characteristics and to evaluate the evolution of the quartz’s liberation degree after fragmentation. The results have shown significant differences in liberation spectrum between the itabirite samples studied. The liberation process of FI was easier than of CI, due its high porosity and larger crystal size compared with CI, which has shown more complex mineral assemblages with low porosity and smaller crystals. The quartz liberation spectrum has shown that grinding at P95 of 0.210 mm for the FI sample, and of 0.045 mm for CI sample, should result in satisfactory liberation for subsequent concentration step.

Aug 1, 2018

By Juan Ruiz-Ornelas, Yousef Mohassab, Ricardo Morales-Estrella, Hong Yong Sohn, Noemi Ortiz-Lara

The effect of mechanical activation on the reduction kinetics of magnetite concentrate by hydrogen was studied. The magnetite concentrate was milled for 8 h using a planetary mill. After the milling process, the average particle size was reduced from 14 to 4.4 m resulting in a lattice microstrain of 0.30. Thermogravimetric experiments were conducted to focus on the chemical reaction as the rate controlling factor by eliminating external mass transfer effects and using a thin layer of particles to remove interstitial diffusion resistance. The onset temperature of reduction was decreased due to the mechanical activation, and the degree of conversion was decreased by sintering of particles which was confirmed by SEM analyses. In view of the results, a reaction rate expression is discussed from which the activation energy is calculated.

Jan 1, 2016

By Yuan She, Qihang Liu, Keng Wu, Hailiang Ren

By observing different coal char’s microstructures and microscopic morphologies during the coking process, the characteristics of COREX coal char’s microstructure and properties were analyzed. MCRI and MCSR were used to respectively describe the reactivity and the strength after reaction of coal char, with those of BF’s coke for reference, and then the physical meaning of MCRI and MCSR were given. MCRI and MCSR were determined by the composition of coal char. For the two kinds of COREX coal, the formula to forecast the hot performance of coal char was set up by making a multiple linear regression between the hot performance and microstructure of the coal char at 1100℃, and the predictive values of coal char’s hot performance at 600℃, 800℃ and 1000℃ coincided well with the measured values.

Jan 1, 2015

By Bi Zongyue, ZhangYongqing, NiuTao, Guo Aimin

Over the past twenty years, significant advances have been made in the field of microalloying steels and associated applications, among which one of the most successful application cases is development and application of heavy-gauge X80 coil with high temperature processing HTP practice used for China's Second West-East pipeline, the longest X80 pipe in the world. During this process, HTP design concept has been sucessfully applied to develop 18.4mm X80 coil with demanding low-temperature fracture toughness requirements. In the meanwhile, China's metallurgical workers have further optimized HTP design concept with the aid of powerful rolling mill and coiling equipment, and made it possible to develop 21.4mm X80 coil used for Russia-China East line. In the paper, we would simply review the development history of high-strength pipeline steels, and then give more priority to the fundamental points for sucessful development of 18.4mm X80 coil and SSAW pipe, which paved the way for subsequent development of 21.4mm X80 coil and SSAW pipe. Finally, we would present the test results of mass production and burst tests, and dispel the suspicion that SSAW pipes made of X80 coil are more qualified to resist ductile fracture.

Oct 1, 2019

By S Bhandari

A model for predicting dust plume dispersion from blasting operations using the Eulerian mathematical algorithm has been developed. This model considers atmospheric stability, and wind velocity and direction for computing dust concentrations at different distances from the blast. Software has been developed which simulates the movement of a dust plume at a given horizontal distance from the blast location and time elapsed after the blast. The concentration of dust is also given in vertical planes. It takes into account ground profile and atmospheric conditions such as temperature, pressure, humidity, wind velocity, wind direction and shear. Experiments were carried out in two limestone mines to calibrate the accuracy of the predictions made by such model. High volume dust samplers were used to collect dust samples. Difficulties encountered in satisfactory dust sampling and quantification of results have been described.

Nov 8, 2011

By G Hart

As the iron ore/magnetite boom gains momentum, it is particularly important to question established past trends and explore the potential of alternative design options. Traditionally, ‘rule of thumb’ methods have been used to size dewatering equipment. Greater consideration needs to be given to technological advancements and specific throughput testing of each ore body type based on innovative developments.This paper will describe how an innovative approach resulted not only in significant savings in capital cost and site work hours but also delivered a truly optimised design for the thickener duty at Karara. Test work also played a crucial role and a comprehensive test work program on the ore samples showed the scale-up benefi ts of new technology in thickener designs. Working closely with the Karara team during the laboratory testing proved the old sizing theories for iron ore/magnetite processing have been superseded with the knowledge and results of the industry’s newest feedwell technology. Increased solids flux and rise rates in the testing process proved very successful, resulting in signifi cantly reduced thickener sizes and lower capital expense.Mechanical design considerations such as removal of underflow and pump access led to a preference for an above-ground thickener confi guration, and the economics of a completefabrication and installation package favoured steel construction for the thickener units.The ultimate choice of the bolted/fl anged tank methodology provides both economic and timely solutions for the site installation including reduced man power and quick and safe site-work. A benefits comparison between this design and other fabrication and installation procedures will also be analysed in the paper.

Jul 11, 2011

By W. J. Miles

Diatomaceous earth or diatomite is a sedimentary rock of organic origin that is composed principally of the silicious skeletal remains of diatoms. Diatoms are microscopic single cell acquatic plants that are related to algae. Diatoms first became abundant in the Cretaceous period from about 65 to 135 million years ago. Most of the commercial deposits are of Pliocene through recent age, and are younger than 35 million years. Diatoms are still abundant in present day lakes and seas. The living diatom is supported and protected by two half cell walls or valves united by a connecting band or girdle. These valves are composed of opaline silica extracted from the water in which the diatom lives. After death of the diatom, the silicious remains settle in the lake or sea and accumulate at variable rates approaching several millimeters per year for very active diatom colonies. This accumulation of silicious sediments, after decay of the organism, burial, and uplift, can result in the formation of diatomaceous earth deposits.

Jan 1, 1987

By Lionel C. Piuze

Introduction and Early History The British Canadian Mine is one of four operating properties of Asbestos Corporation, Limited, and is located in the town of Black Lake, Que., five miles southwest of Thetford Mines. In the early days of as1bestos mining, this .property was owned by a few small companies who later became part of the Asbestos Corporation. First .to commence mining operations on the property was the Coleraine Mining Company who, in 1885, began selling part of their large holdings in the area to various asbestos mining interests. Of these, the earliest active companies were Manhattan United Asbestos, the Glasgow and Montreal Asbestos Company, and the Anglo-Canadian, the last named later becoming the Standard and Dominion Asbestos Companies. Extraction of fibre was limited to what is now known as crude asbestos and the methods were primitive. Drilling was done .by hand and the ore was lifted by derricks operated by band winches. These were later replaced by horse power, but it was not until 1887 that the first steam-operated boom derricks were introduced, at the Anglo-Canadian mine. The ore was hand cobbled and the asbestos roughly classified and bagged. The waste rock, which by today's standards contained a considerable percentage of marketable fibre, was dumped near the pit. The first attempt to separate the asbestos from the host rock by mechanical means was made in 1888 by the G1asgow and Montreal Asbestos Company, then known as the Scottish-Canadian Asbestos Company, whose mill, erected in that year, was the world's first asbestos mill. Though the equipment was crude, the principles employed were the same as those used today with much larger units. The next steps were the use of rock drills, the adoption of steam rail transportation for moving mill rock, and conversion to the more flexible cable-derrick hoisting.

Jan 1, 1950

The Energy Authority of NSW has wide powers and responsibilities conferred by its Act which are pertinent to the State's coal industry and its development into the next century. With respect to coal, the broad objective is to maximise the benefits to NSW and its people derived from the State's coal resources. The initial focus of the Authority's coal-related activities in the late 70's and early 80's was on petroleum substitutes from coal. Research was supported, especially on hydrogenation, and the Authority participated in the Joint Australia/Federal Republic of Germany coal-to-oil feasibility study. It also co-ordinated a State Government initiative to involve the private sector in examining the possible establishment of a synthetic fuels industry based on Hunter Valley coal. With a short-fall in world-wide petroleum supply now seen as less likely for some years, the Authority is looking also at ways of working towards the broad objective in the field of coal utilisation on both domestic and export markets. Areas of interest include possibilities for using washery rejects, means of making NSW coal more competitive as an energy source, use of coal-seam gas and new or special technologies for burning coal. The future is expected to see renewed interest in producing petroleum substitutes, and coal - as the State's major energy resource - is seen as a strong contender as a basis for such an industry. Developments in coal-based power generation are also expected to have an impact, with advanced technologies having a possible place here as well as Overseas.

Jan 1, 1987

By John J. Laffin

"Nova Scotia Department of Mines and Energy Throughout the history of Nova Scotia, trends in the production and use of its coal resources have resulted in major impacts on the economy and society of the province. Current trends in coal demand locally, nationally and internationally are having and will have an increasing positive effect on Nova Scotia over the next twenty years-in terms of energy supply, job creation and general economic development. Coal for electrical generation is an immediate and key objective of Nova Scotia's energy plan; and, in the long term, coal-derived fuels will meet the province's needs for transportation fuels. Demand for metallurgical coal is also expected to increase, especially if the merchant coke plant currently under investigation becomes a reality.Meeting these coal supply and utilization objectives in the face of increasing environmental, social and economic constraints poses a tremendous technical challenge. Work has begun on projects to expand coal production capacity and to adapt new technologies for coal preparation and utilization to the specific needs of Nova Scotia; much more work will be required in the coming decade in order to succesfully tap this resource.IntroductionThe energy problem facing Atlantic Canada has a few unique features not found in the rest of the country. Canada, as a whole, has access to a diverse mix of energy resources, including crude oil, natural gas, coal, hydro and uranium, with the result that crude oil supplies only about 40 per cent of Canada's primary demand. In contrast, foreign crude oil dominates Atlantic Canada's energy mix, supplying over 70 per cent of the primary energy demand.This results in important differences in various sectors. Nationally, about 5 per cent of the electricity is generated from oil whereas last year in Nova Scotia approximately 40 per cent of the electricity generated was from imported oil. Residential, commercial and industrial space heating, and industrial process heating in Atlantic Canada was almost 100 percent dependent on foreign oil. This is in sharp contrast to the situation in central and western Canada, which have access to secure domestic natural gas, oil and hydro electricity."

Jan 1, 1982

By Rudolf Hubmer

In October 2013 JSW Steel decided to place an order to Primetals Technologies Austria (former Siemens VAI Metals Technologies) for the installation of a comprehensive Level 2 process optimization system for more than 20 existing production facilities of various suppliers. For SMS-I new L2 systems are provided for two hot metal pretreatment stations, three hot metal desulphurization stations, three ladle furnaces, two 1-strand slab casters, a ladle tracking system as well as a shop supervisory system. Additionally the existing L2 system for one 1-strand slab caster is being upgraded in the course of the project. In SMS-II new L2 systems for the 7 hot metal desulphurization stations, 4 ladle furnaces, 1 new RH vacuum degasser, ladle tracking system and a shop supervisory system are supplied. Despite of the challenging time schedule the commissioning of the single facilities started within less than 12 month after contract effectiveness. The installed Level 2 process optimization systems together with the achieved results are described in this paper.

Aug 16, 2017

By Hugo Leandro Rosa

A CBMM aplicou aços micro ligados ao nióbio em dois tipos de caçambas de carregadeiras de rodas que operam na usina de Araxá, Brasil. O objetivo foi avaliar os benefícios destes aços relacionados com redução dos custos, aumento da produtividade e vida útil dos componentes. Uma das máquinas analisadas coleta peças quentes de ferro nióbio para carregamento dos silos do britador. O uso de um aço ferramenta de alta resistência e resistente ao desgaste solucionou os problemas de deformação, desgaste e rachaduras durante o serviço, aumentando a vida útil da caçamba em cerca de 190%. A outra máquina avaliada foi uma carregadeira de rodas que opera na mina de minério de nióbio. O novo desenho com aços de alta resistência mecânica e resistente ao desgaste reduziu o peso em 14%, correspondendo ao incremento na capacidade de carga. A carga extra possibilitou um aumento na produtividade dos caminhões de 42 toneladas. Com os novos materiais, as trincas anteriormente encontradas na caçamba da pá carregadeira foram eliminadas, enquanto foi mantida a resistência ao desgaste antes oferecida pelo aço revestido com carbeto de cromo reduzindo também os custos de investimento em 7%.

Aug 17, 2017

By Kermit Reins

The most recent modernization phase of the wire rod mill at Sterling Steel involved installation of a pre-finishing mill, using a Morgan Vee Mini-Block, a new water box and shear with utility systems and automation. The new mill configuration adds more stands to the mill for better drafting and is designed to improve finished product quality by providing a more uniform entry temperature, better control of the feed section into the No-Twist® mill as well as enhanced surface quality. The new shear improves cut length accuracy as well as decreases the amount of trimming to reduce yield loss. This paper explains the changes made in the mill and the features of the new equipment and automation.

Aug 17, 2017