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By J. Perlacia

Introduction The Bulk Handling Technology has already started its transformation to the Industry 4.0. Having some of the harshest working and environmental conditions of the industry, the possibility of remote analysis and maintenance of the components seems a perfect target to focus on. The most important and expensive tools have been adapted to the digital era during last years, from remotely controlled haul trucks to monitored conveyor belts. However, these big parts of the installations rely in smaller parts that have been left aside for a while, mainly due to the difficulty to adapt them to IoT (Internet of Things). The paradigmatic example is the lack of monitored rollers whereas all the other components of the conveyor belt installations (the belt itself, motors, drums etc.) were monitored some time ago. The main problem is that a failure of a single roller can cause the stop of the whole conveyor, due to the possible damages to the belt, thus the implementation of an integral monitoring system of all the components of the conveyor is a must. The R&D Department of ULMA Conveyor Components, has been working since early 2012 on the development of Monitored Rollers, facing all the problems until its final installation in very different demanding conveyors, from the Australian extreme heat to the freezing cold Norway. All the tests done under actual working conditions, in real installations, have given a valuable knowledge in the identification of problems, their solution and the final advantages of a roller monitoring system. Background and Current State The malfunction of a single roller in certain conveyor belts can suppose the standstill of the whole installation until its replacement, due to the risk of greater and more expensive failures like the rip of the belt. In the case of a bulk handling installation where a continuous supply of material is necessary, an unexpected stop of one hour could entail huge economical losses. What’s more, many conveyor belts are several kilometers long or the access to some parts of them is very complicated. Due to these difficulties the inspection and maintenance operations can become expensive and hard going, with staff going over the whole area checking the correct condition of the conveyor and rollers, which means a dangerous activity. As in many other industry products, the condition of rollers can be recognized measuring key parameters like the temperature of the bearings, the vibration level etc. The traditional way is to use the characteristic noise of a failing bearing, but this method usually implies to change several rollers because the maintenance team is not able to identify a single source of the noise. In recent years different attempts to measure the temperature of the bearings have been made, but the result is not accurate enough due to the proximity of the rollers in the idlers

Jan 1, 2019

By M Bellamy

The DeGrussa copper deposit was discovered by Sandfire Resources in April 2009. Construction of the 1.6 Mt/a concentrator, open pit and underground mining operations commenced in March 2011 with first concentrate production achieved in October 2012. Over the next ten years, DeGrussa grew to include both the DeGrussa and Monty underground mines, establishing itself as one of the world’s premier copper producers with total production of 663 000 t of contained copper by the time the mine closed. Final ore was trucked from Degrussa on 5 October 2022. This paper examines the mine closure experience from both a planning and operational perspective. The paper provides an overview of the site’s mine planning process including the factors involved in determining the end of the mine life and how this was tracked and communicated in the lead up to the end of mining operations. It will also look at some of the specific operational aspects involved in maintaining steady state production all the way through to the last day while facing increasingly challenging conditions. These factors, along with the external factors faced by most of the industry such as labour shortages and COVID related disruptions, contributed to making it an interesting journey to the end of operations at DeGrussa.

Mar 29, 2023

By S van der Sluijs, M van Ende, Y Tang, A Emami

This paper presents a phenomena-based model for investigating the possibility of scrap melting in an Open Slag Bath Furnace (OSBF) for green ironmaking. The goal of this study is to enhance the circularity of the steelmaking process by utilising scrap as a green source of iron in OSBFs. The model takes into account the fundamental differences between OSBFs and traditional processes such as Electric Arc Furnaces (EAFs) and Basic Oxygen Furnaces (BOFs). The model considers three primary regions where scrap heating and melting occur: the solid feed pile, slag and hot metal. It accounts for factors such as the furnace geometry, scrap charging mechanism and specific heat and mass transfer properties of the reactor. The model was validated using literature data and was used to investigate the heating and melting behaviour of individual scrap particles under various process parameters. The study finds that the scrap melting process in OSBFs involves three stages: shell formation, shell remelting and subsequent melting of the parent scrap. The carbon content of the scrap and the liquid hot metal plays a critical role in determining the melting behaviour. Depending on the carbon concentration and temperature, the melting process can be heat transfer controlled or mass transfer controlled. The paper also examines the scrap feeding methods in OSBFs, including direct charging into the slag or charging through a feed pile. The model provides insights into the melting rate of scrap compared to Direct Reduced Iron (DRI) in OSBFs and highlights the role of carbon in this process. Overall, this phenomena-based model contributes to the understanding of scrap melting behaviour in OSBFs and provides valuable insights for optimising the circularity and efficiency of green ironmaking processes. The findings of this study can inform the design and operation of OSBFs, paving the way for increased utilisation of scrap as a sustainable feedstock in the steel industry.

Jun 19, 2024

By Karin Bäppler

Mechanized tunnelling is undoubtedly one of the most innovative disciplines in the international construction industry. Technological progress in the planning and production of most modern infrastructure is constantly striving for new records on basis of highly specialized solutions and know-how. Humans and technology have accomplished excellent achievements over the past few years in varied, difficult terrain. New length records are being set with the 64 km long Brenner Base Tunnel and the HS2 Railway system currently under construction in Europe. Cities are building ever longer and more demanding sewer tunnels. The paper highlights some of the challenges, trends and innovations of long-distance tunnelling projects.

Dec 1, 2022

By Yan Lap J. Kan

"A waterfront stabilization system consisting of Deep Soil Mixing (DSM) columns, vinyl sheet pile fascia, and concrete flood walls supported on shallow footings was designed and constructed for a high-density waterfront development in Northern California. The project site is underlain by soft, compressible organic soil locally known as Bay Mud that has been capped with loose sand and imported fill. The waterfront stabilization system constructed at the site mitigates liquefaction, consolidation settlement and seismic potential slope deformation along the waterfront; the system was designed to reduce lateral displacements to tolerable amounts for the proposed structures. This paper presents the general design methodologies, construction challenges and quality control of this waterfront stabilization system.INTRODUCTIONUrban development in Northern California is fueling innovations in geotechnical engineering as more complex sites are developed. ENGEO Incorporated introduced a deep soil mixing technology from Japan to the US and designed a waterfront stabilization system for a high density waterfront development project in Redwood City, California. The approximately 12½-acre project site, as shown on Fig. 1, is surrounded by water on three sides, with an inner marina at the center of the site.The project site is located in the seismically active San Francisco Bay Area in California. The San Andreas Fault, the Monte Vista-Shannon Fault, the Hayward Fault and the San Gregorio Fault are major active faults located within 25 miles of the site. Once a former marshland with a major slough until the late 1950s, the site was reclaimed by placing imported fill over the native compressible clay deposits, locally known as Bay Mud."

Jan 1, 2016

By Guy Bridges, Elton Ko, Cheng Ting Ning, Owen Ng, Giovanni Chang, Robert Anderson

"PROJECT OVERVIEWThe Liantang/Heung Yuen Wai Boundary Control Point (BCP) and Associated Works will be the seventhland crossing between Shenzhen and the Hong Kong Special Administrative Region (HKSAR) of China.The project includes site formation of about 23 hectares of land for the development of the BCP and anapproximately 11-kilometre (km) long dual two-lane trunk road (the “Connecting Road”), connecting theBCP with the existing Fanling Highway. The route alignment is within a relatively rural area of HongKong, with very limited similar infrastructure works carried out nearby. It passes beneath bothmountainous terrain, and alluvial plains, and falls within an area of several major regional faults andassociated metamorphism, resulting in a complex variety of ground conditions.ALIGNMENTThe Civil Engineering and Development Department of the Government of the Hong Kong SpecialAdministrative Region carried out extensive public engagement in selecting the alignment of theConnecting Road. Over 70 consultation forums with public bodies, including the District Councils, RuralCommittees, local representatives, etc. were held during the alignment design process. In order toalleviate the concerns of various nearby villages, and to minimize land clearance and environmentalproblems, the original alignment of 10 km long (3.5 km of tunnels and 6.5 km of viaducts) was revised toits final alignment of 11 km long which comprises 5.7 km of tunnels, 4.3 km of viaducts and 1.0 km of atgrade roads.The finally adopted alignment commences at the southern end with an interchange with the existingFanling Highway, part of Route 9, which is a dual three lane expressway currently being widened to dual4 lane. Alongside the expressway is the main rail connection to the mainland of China, and theinterchange viaducts connecting to the southern portal of the Lung Shan tunnel must cross over thisrailway. The southern portal is located in the foothills of Lung Shan, and the 4.8km long tunnel is alignedin a north-northeasterly direction. The southern half passes under mountainous terrain of Lung Shan,and then crosses a valley containing the Kwan Tei river. The northern section comprises low hillsseparated by an alluvial plain and Tan Chuk Hang village area. At the northern end, the tunnel turns tothe north-west to connect with Sha Tau Kok road, an existing single carriageway road, with a newroundabout interchange. Mid-way along this tunnel there will be a ventilation building, connected to the main tunnel by a 330m long ventilation adit. To the north-western side of this interchange is the900m long Cheung Shan tunnel, and after this the remaining 4.3km of the highway connecting with theBoundary Control Point is to be constructed as an elevated viaduct. The alignment is shown in Figure 1."

Jan 1, 2016

By P. Stefanek, N. Duda, B. Jachni, P. Stefaniak, B. Bursa

The Zelazny Most Tailings Storage Facility (TSF) is the largest reservoir of post–flotation tailings in Europe. The total amount of tailings from the mines in Lubin, Rudna, and Polkowice are stored each year at the disposal facility, which reaches approximately 30 million tons. It is crucial to accurately monitor and maintain such a huge storage facility, for the safety and economics of the entire region. In general, the monitoring network installed at the Zelazny Most TSF includes four groups of components: (a) geotechnical network (VW pore pressure transducers and inclinometers), (b) hydrological network (open piezometers, water level gauges, drainage discharge measurements, (c) geodetic survey network (e.g. surface and in-depth benchmarks, laser measurements, GPS measurements within GEOMOS network and (d) seismic network (e.g. accelerometer stations, cone penetration tests.) Apart from the above, chemical water analyses, tests of soil samples, monitoring of spigotting processes, and monitoring of relief wells’ discharge are also conducted. In total, approximately 2900 monitoring instruments are installed within the area of the Zelazny Most TSF. Such large amounts of data from the various information sources makes manual data analysis by the engineers almost impossible. In this paper we discuss a machine learning driven approach to improve the quality of the monitoring and maintenance of such facilities. We focus on the seismic cone penetration test (SCPT) data analysis. First, we carefully describe the collected data, its quality and availability. Then we discuss possible events that can occur in the TSF that need to be predicted using SCPT. Based on the information obtained in these two steps, the applicability of several machine learning methods is estimated. Some of them are then tested on available historical data. The algorithms described in this article will be further developed in the IlluMINEation project (H2020).

Sep 1, 2021

By J. Githiria, D. Wachira

The conventional truck and shovel haulage system has become expensive to operate in most mines due to current strict environmental conditions, increase in depth and size of open-pit mines, increase in labour costs, and fuel costs. These factors have motivated the search for alternative material haulage options in open-pit mines. In-pit crushing and conveying (IPCC) system has been regarded as a plausible alternative in material haulage systems. However, usage of IPCC has been limited to a few mines due to limited knowledge of IPCC performance, and other technical factors of the system. This paper investigates, and evaluates the productivity performance of four types of IPCC systems (fixed, semi-fixed, semi-mobile, and fully mobile IPCCs) using mine productivity index (MPi). Using a model developed by MATLAB, the MPi for the four systems is computed using input variables such as availability, utilisation, performance and number of trucks and shovels in a limestone quarry. The mine productivity index for fixed, semi-fixed, semi-mobile, and fully mobile IPCC is obtained as 67.13%, 69.02%, 70.52%, and 71.52% respectively. In conclusion, the fully mobile in-pit crushing and conveying system is the most appropriate IPCC in the quarry, due to its better productivity performance compared to the other three IPCC systems and the truck and shovel system currently in use.

Sep 1, 2021

By Jerry C. Tien

The rare earth elements (REEs) are a group of 17 chemical (metallic) elements which appear in the periodic table. The group consists of 15 lanthanide elements along with yttrium and scandium (Table 1). They share many similar properties, which is why they occur together in geological deposits. Although commonly referred to as rare, they are really quite common; the reason they are perceived as rare is because it is not common to find them in commercially viable concentrations. These metals are critical to advanced technology, ranging from smart phones to global positions system (GPS) receivers, medical devices and jet engines. They are critical in green, high-tech and defense industries (Fig.1 and 2). Although there have been increasing efforts to find alternative supplies, these efforts have been complicated by the pollution that rare earth mining and processing creates. To extract rare earths minerals from mined ore is a complicated and costly process. The ore is first mined through normal mining process, the bastnaesite, which generally contains a number of minerals of little value, is first removed through a floatation process. The bastnaesite containing the REEs is further separated into their respective pure forms in a separation plant using acid and various solvent extraction separation steps. Each element has its own unique extraction steps and chemical processes. At times, these elements, in the form of oxides, will require reprocessing to achieve ideal purity. The last steps would be to further process into metals first, then alloys for various applications. The entire process takes approximately 10 days. The mining and processing of REEs, if not carefully controlled, can create environmental hazards. This is one of the reasons the Mountain Pass Mine in California was closed down in the 1980s.

Dec 1, 2013

By Susanne Pignolet-Brandom

Reflected light microscopy scanning electron microscope energy dispersive spectroscopic analysis and backscatter electron image and electron microprobe chemical analysis have been used to study lead sinter and lead blast furnace slag. These studies provide invaluable information on the phases present their intergrowths, and their chemical composition. Such information increases the understanding of the nature of pyrometallurgical processes and the behavior of minor elements during these metallurgical processes.

Jan 1, 1987

By Alfred H. Brooks

The developments of the past five years have shown that Alaska, as a field for mining, stands in the first rank among the possessions of the United States. Its annual gold output is now about $8,000,000. It produces silver, copper and coal in commercial quantities and its recently discovered tin and petroleum promise to become important products. Concurrent with the gradual development of this wealth, the mining public has ceased to regard the territory simply as an arctic province where a few placer-miners struggle with adverse conditions to secure a grub-stake or a modest fortune. Of late years there has been a large influx of capital to investigate its mineral resources, but in its area of nearly 600,000 sq. miles there still remain large, unexploited and little-known fields. This work of investigation has been carried on under adverse conditions, and reflects credit on all who have shared in it, whether prospectors, mining engineers, or geologists. It is the purpose of this paper to outline briefly what has been, and is being, accomplished toward furthering the knowledge of Alaska's mineral wealth, and in this connection to present a brief history of the operations of the United States Geological Survey in the territory. A list of the publications of the Geological Survey, which pertain to Alaska, is presented as an appendix, in the hope that it may prove useful to those who are interested in the mining of this northern province. During the Russian occupation of Alaska, from 1783 to 1866, but little attempt was made to delineate its geographic features or to study its geology and mineral resources. The Russian-American Co., which long held control of the territory, was entirely absorbed in the exploitation of its fur trade,

Jan 1, 1905

By Fuad S. Maayeh, Robert J. Evans, Paul M. Yavorsky

A description and capabilities of the Mine Roof Simulator at the Pittsburgh Mining Technology Center is illustrated for testing longwall roof support equipment. This unique Mine Roof Simulator has the capacity to exert 3 million lbs. of compressive force vertically and 1.6 million lbs. of force horizontally to simulate loads on hydraulic supports typically found in longwall mining. The supports that undergo testing are instrumented with strain gauges and photoelastic coatings such that critically strained areas become readily apparent. These critically strained areas are redesigned or retrofitted with appropriate reinforcement and retested. A data base will be accumulated from several support designs that will lead to an optimized design that will have the potential to reduce downtime by malfunctions of supports and thus increase productivity. A typical test procedure and analysis is given for a two leg 350 ton shield along with a description for placement of strain gauges, displacement gauges, and hydraulic pressure monitors for critical sites.

Jan 1, 1982

By John T. Wizzard, R. P. Killmeyer, B. S. Gottfried

The Coal Preparation Branch of the Pittsburgh Energy Technology Center has developed a computer program to calculate the performance characteristics of coal washing devices. This program uses specific gravity analyses of the clean coal and refuse streams as input, and generates dependent and independent performance criteria for the washer. Partition curves are internally represented in a functional form by a Weibull function. Performance criteria generated by this computer program are compared to manually calculated performance criteria for air tables, Dynawhirlpools, Baum jigs, hydrocyclones, and dense medium cyclones. The comparisons show that the computer program gives results in close agreement with the hand- calculated values while greatly reducing the amount of time involved in performing the analyses.

Jan 1, 1983

By Sarkar B. C, Sen A. K

India is well endowed with vast reserves of banded hematite ore, about 12 billion tonnes, estimated by some conventional methods. Various authors have assessed this huge reserve using some advanced geostatistical methods. A Banded Iron Formation (BIF) belt named the `Singhbhum-Keonjhar-Bonai' belt in India has been chosen as a case study. In this paper, the experiences of Chiria iron ore, in particular, have been described. This study will finally create a dynamic mineral inventory after standardising the geostatistical parameters which will help to cater for the needs of the stringent quality requirements of the Indian steel industries.

Jan 1, 1995

By Henry Zhang

This paper presents two case studies of large diameter driven tubular steel piles for the ongoing Woolgoolga to Ballina Pacific Highway upgrade (W2B). This project forms part of Australia’s largest regional infrastructure project and will upgrade about 155 kilometers of highway to four-lane, divided road. There are more than 170 bridges on W2B, and driven tubular steel piles are adopted on 43 bridges between Glenugie and Ballina. Driven piles terminating in soil or basalt is a big challenge faced by both designers and piling contractors due to 1) the uncertainty of expected pile unit shaft and base resistance in different soils; 2) whether plugging is formed; and 3) highly variable basalt strength and thickness near top of the rock. If these risks are not adequately managed during design or construction stages, it could lead to unexpected project delay, extra time and cost or pile toe damage in basalt. This paper describes two case studies, one for piles designed to terminate in soils and the other for piles designed to terminate in basalt. How these risks were assessed and managed during detailed design, procurement, hammer selection, pile installation and verification will be discussed in details with lessons learnt summerised in the conclusion.

Nov 1, 2022

By Qingwei Joshua Ong

Tension piles, also known as uplift or anchor piles, are necessary to resist uplift forces that might cause structural distress. In excavation projects, most uplift forces are developed because of hydrostatic pressures, and so tension piles are subjected to a great deal of tensile forces. Most current methods of design for tension piles completely neglect the tensile strength contribution of concrete, relying only on the steel members to carry the tensile stresses, resulting in an overly conservative design. The stressstrain behavior of the composite material of concrete and steel must be considered for a realistic simulation of tension piles. This paper will examine a case on a tension bored pile in typical soft clay to demonstrate the importance of considering the tension strength and tension softening of the concrete.

Nov 1, 2022

By Nick M. Withers, Suthagarann Visvalingam, Cillian Mc Colgan

The level crossings removal project in Victoria is removing 75 level crossings across Melbourne to improve safety by separating trains from traffic, with other benefits such as reduced congestion, an upgraded road network, connected communities and support of urban regeneration. The level crossing at Station Street in Carrum forms part of the scope being delivered by the Southern Program Alliance (SPA), which is delivering level crossing removal works associated with the Frankston Train Line. At Station Street, a rail viaduct consisting of 19 spans and totalling approximately 545 m in length is under construction to remove the former level crossing. The viaduct consists of two parallel reinforced concrete Utrough girders and steel trough girders, one for each rail line. The foundations of the rail viaduct are founded on groups of Continuous Flight Auger (CFA) piles. The characterisation of geological units encountered at Carrum for the foundation design has been based on insitu testing and interpretation of test results from high strain dynamic pile testing (PDA) and Case Pile Wave Analysis Program (CAPWAP) from the Seaford Road Bridge, located approximately three kilometres South of Carrum, in similar ground conditions. By conducting pile load-deformation analyses based on pile testing significant savings were made for the client compared to the original design which was based on more traditional empirical correlations. This paper discusses the pile design methodology adopted using pile test data for this viaduct foundation. The results of this assessment are also compared to existing empirical correlations, and the limitations are discussed. The performance of the adopted pile design methodology using pile test data at Carrum rail viaduct is also discussed.

Nov 1, 2022

By George Moses K, Mahendran K

Grouting is performed in rock masses in order to increase its strength properties and also to reduce the seepage. In the design of underground structures such as tunnels or caverns located in weak rock masses, grouting plays an essential role. Grouting is a complex process demanding high degree of skill and knowledge in understanding of grout flow and requirements for certain geological conditions. This paper discusses the design process for grouting in rock masses adopted for a cavern project and the practical difficulties faced during the execution at site. The design parameters of grouting includes the injection pressure, grout material properties and stopping criteria. The paper also discusses the various tests performed at site to evaluate the efficacy of the grouting process which was initially defined based on the design and previous experiences. The final grouting scheme suiting to the present geological condition is arrived based on the test results. The practical difficulties faced during the execution and the measures taken to overcome these are discussed in detail. This work shows the importance of state of art in the development of a grouting process based on geological and hydrogeological conditions prevailing at site and can be helpful in grouting design for weak rock masses.

Nov 1, 2022

By Cláudio Antunes de Oliveira

O objetivo deste trabalho é utilizar o vasto banco de dados de informações de processo armazenadas pelo InfoPlus.21, que é um exemplo de sistema PIMS - Plant Information Managment System, para implementar um sensor virtual a partir de um modelo neural visando obter a tendência de resposta da variável consumo específico de uma caldeira. Propõe-se também, extrair diagnósticos do processo através do emprego da Lógica Fuzzy. As etapas de treinamento da rede neural e o desenvolvimento do diagnóstico envolveram simulações no software Matlab. Os resultados obtidos demonstraram-se bastante satisfatórios. Destaca-se a tendência de resposta do sensor virtual que apontou 97% de confiabilidade. Por fim entende-se que as propostas deste trabalho foram alcançadas, principalmente pela implementação inovadora do sensor virtual no InfoPlus.21 por meio da ferramenta SQLPlus, a qual possibilitará novas aplicações no meio industrial.

Jul 30, 2018

By H. R. Hernandez-Guerrero, S. A. Robles-Salazar, M. Marín-Pasillas, P. J. Pompilla-Rosales

Peña Colorada is a company dedicated to the exploration, exploitation, and beneficiation of iron ore, serving the national steel industry. Established in 1975 as a stateowned enterprise, it transitioned to operating as a private organization in 1991. It is jointly owned by two investors, ArcelorMittal and Ternium, each holding a 50% stake. The mining operation is situated in the municipality of Minatitlan, in the northwestern part of the state of Colima, Mexico (Figure 1). It comprises an open pit mine and a concentrator, covering an area of approximately 2,300 hectares. The pellet mill is in the town of Manzanillo, Colima state, a port on the Pacific coast, about 46 km southwest of the mine. The pellet mill occupies its own property with a total area of 60.4 hectares. A gravity-driven concentrated slurry pipeline connects the mine and the pelletizing plant, located at an average elevation of 1,020 meters above sea level and 20 meters above sea level, respectively. Currently, Peña Colorada produces 4.1 million tons of pellets and 0.4 million tons of iron concentrate annually. In 2018, due to a change in the cutoff grade, the processing volume of the beneficiation plant increased from 9 million tons to 16 million tons annually. This led to a greater amount of information to process and characterize the ore extracted from the pit before its processing in the beneficiation plant. Consequently, Peña Colorada sought new ore control technologies to enhance ore selection, optimize human resources and data management, as well as minimize discrepancies between planning and execution. To ensure adherence to quality agreements with stakeholders, it is crucial to understand the ore characteristics before initiating mining activities.

Feb 1, 2024