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By J. Grubb

"The undertakings described in the paper titled “Study on correlation of quantified coal rank with self-heating temperature” by Wang and Luo in the November 2015 issue of Mining Engineering (Wang and Luo, 2015) are mathematically sustainable and an acceptable extension of work performed by Smith and Lazzara (1987) for the U.S. Bureau of Mines. The paper is not an accurate explanation of the currently accepted leading practice for determining the propensity of a coal seam for spontaneous combustion. The paper could lead a practitioner to an oversimplified conclusion on how to determine the propensity of a coal seam to spontaneously combust.The spontaneous combustion of coal is a complex and not fully understood reaction. What is understood is that many more factors other than selfheating temperature (SHT) and coal rank are required to sufficiently evaluate the risk of spontaneous combustion in a particular coal seam. A superficial assessment can lead to an improper response to the risk. Some statements on the next steps through an appropriate literature search would have made the authors’ conclusions more credible.The SponCom 2.0 software, updated by the National Institute for Occupational Health and Safety (NIOSH) in 2011, provides a path for evaluating the susceptibility of a coal seam to spontaneous combustion. In addition to proximate and ultimate analyses to establish coal rank, and therefore an estimate of SHT, the program includes the history of heatings, friability, seam thickness, overburden thickness, rider seam presence, pyrite presence, face and butt cleat densities, geothermal source presence and other geological features in the assessment. Mining conditions including floor heave, rib sloughage and rate of advance are also assessed to conclude a propensity for spontaneous combustion."

Jun 1, 2016

By H Arvidson, Rondinelli Sousa, Nic Pollock, Cesar Carrasco, Boz Elloy

Global public mineral reporting codes have driven strong governance of public disclosures of minerals information. Recently, we have seen an increase in disclosure of information related to Environmental, Social and Governance (ESG) issues, and governance of ESG information in mining companies has arguably reached a similar level of governance and diligence afforded mineral reporting. We define Resource Governance as the conjunction of environmental, social and minerals governance. A modern systems approach to Resource Governance, which combines mineral and ESG information, would provide not only reporting and governance capability, but also has the potential to sense/respond, predict, and manage ESG risks.

Feb 1, 2024

By C. Fuellenbach, J. Brune

"INTRODUCTION Mining activities must be safe and profitable. These two requirements influence each other. The purchase and implementation of safety improvements costs money. Injuries and illnesses at mines stop or delay production and may result in additional costs or a loss of profit. Other effects of injuries and illnesses include the negative influence on employee morale, corporate reputation and conflicts with contract partners. Based on this researchers asked the question: are mines with lower rates of injuries and illnesses more profitable than mines with a higher frequencies? One aspect of this research is the evaluation of the safety situation and the measurement of benefits of safety improvements in the German mining industry. In the following paper, this part of the research will be examined. The main aim is the evaluation of injury rates in different German mining sectors and regions in Germany. SELECTION OF GERMAN MINING OPERATIONS The research team decided to focus the study on the salt and potash and the aggregate and industrial minerals mining industries in Germany. These two mining industries are different in the number and size of operators, structure of the industry, pricing and markets. The selection of two different industries adds to the clarity of the evaluation. Salt and potash mining industry The German salt and potash industry is primarily located central Germany. All salt and potash mines in Germany are underground operations. In 2015, the German potash industry employed 8,100 employees and generated a total revenue of 2 billion Euros. German potash reserves include magnesium compounds like kieserite (MgSO4·H2O), in addition to sylvite (KCl) and carnallite (KMgCl3·6(H2O)). The German salt industry employed 2,300 people in 2015 and generated revenue of 800 million Euros (Krueger, 2015) There are seven mining companies with salt and potash operations: esco-european salt company GmbH & Co. KG, K + S Kali GmbH, Saline Luisenhall GmbH, GSES Glückauf Sondershausen Entwicklungs- und Sicherungs-gesellschaft GmbH, Südwestdeutsche Salzwerke AG, Wacker Chemie AG and Südsalz GmbH. In this way, esco – european salt company GmbH & Co. KG is an affiliated company. Esco was founded as a joint venture of K + S and Solvay in 2002, since 2004 K + S is the sole holder (esco - european salt company GmbH & Co. KG, 2016). Likewise, the Südwestdeutsche Salzwerke AG has a controlling interest in Südsalz GmbH (Südsalz GmbH, 2016). Aggregate and industrial minerals mining industry The aggregate mining industry in Germany is comprised of many small mining operations and relevant companies. According to the German Department of Economics (BMWi, 2015), the following industrial materials are classified as aggregates: fluorite, barite, kaolin, quartz and quartz sand, quartzite, silica, loamy and foundry sand, pegmatite sand, shale, clay, bentonite, schistose, limestone and dolomite, gypsum and anhydrite, basaltic lava and lava sand, gravel and split, pebble and silicic sand and peat."

Jan 1, 2017

The methods used by Newmont Gold Company for deposit modeling are illustrated by examples taken from current operations and advanced projects. These methods vary depending on a number of factors, including geology, mining and processing methods, economic feasibility, and availability of historical information. It is argued that successful modeling requires understanding these factors, knowing the strengths and weaknesses of the various modeling techniques, and being flexible in selecting the appropriate methods.

Jan 1, 1997

By Michael Cruickshank

All life on Earth relies on the ocean and yet the ocean is 95 percent unexplored, unknown and unseen by human eyes,? said Paula Keener, director of education programs for National Oceanic and Atmospheric Administration?s (NOAA) Office of Ocean Exploration and Research. ?To better understand, manage and protect the ocean and its resources, NOAA believes it is critical to use the best technology to explore, discover, inform, educate and motivate? (MTS, newsletter, January 2011). In the last few decades, our understanding of the global mineral resource base has been drastically changed by some surprising new developments. The potential for commercial minerals per unit area in the oceans and seabed appears to be similar to that of the terrestrial lands. Thus, almost three-fourths of the global mineral resources are in, or under, the sea and are virtually undeveloped. The area of the Pacific seabeds alone is greater than the total area of the global lands. Half of the global seabed minerals are now controlled by nation states within their Exclusive Economic Zones (EEZ). The other half is controlled by the United Nations (UN) through the International Seabed Authority (ISA) within the ?areas beyond national jurisdiction? known as The Area. Thus, the Law of the Sea, ratified in 1994, has resulted in the largest transfer of control of natural resources in the history of mankind. This paper was prepared by the Society for Mining, Metallurgy and Exploration (SME) Committee on the Offshore Technology Conference for the SME Board of Directors and other interested parties. As the premier professional society for the mining and mineral community in the United States, with a history dating back to the 19th century, SME?s mission is to encourage and support young men and women engineers in the minerals industry, provide the services they need, improve the image of the industry, strengthen the networking among global industry professionals and engage in proactive collaboration among industry, government, academia and nongovernmental organizations (NGOs). The accomplishment of this mission can be strongly advanced by highlighting what is probably now the most significant development in the history of the modern minerals industry - the exploration of the marine environment and the understanding of the potential for the development of the minerals therein.

Jan 1, 2011

By A. E. Koski

This paper describes the implementation of specialized software in mine planning at the Cleveland-Cliffs' managed Empire Mine on Michigan's Marquette Iron Range. The application puts together years of mining experience on the eastern end of the Marquette Range beginning in the early 1960's. The Empire Mine, in its thirty-fifth year of production, uses the software to model a complex and highly variable low grade magnetite ore body, capturing the economics of mining and processing to the final product. With special attention given to geostatistical methods, the software is used for all geologic modeling, ore reserve estimation, ore control, pit design and short and long range planning.

Jan 1, 1999

By H. V. Scotland III

Lafarge Corporation's Texas Quarry, in Baltimore MD, achieved a substantial expansion of pit reserves by removing an inactive underground mine. The day lighting program, designed, and completed in 1997, open pit mined more than 400 meters of room and pillar workings which were originally developed to recover high brightness Calcium Carbonate. The project proved to be a challenge throughout its course as the pit plan was modified and successful daylighting techniques were developed to remove the mine without adversely affecting the safety of the operation, quality of the stone recovered, or negatively impacting the surrounding community. The design parameters and techniques developed and implemented at Texas may prove of interest to other operators as they are faced with daylighting opportunities. This article will detail the challenges we faced and the solutions which made the project a success.

Jan 1, 1999

By G. Vogt

Water is one of the most important ressources of our planet. Unlike many other natural resources, water cannot be substituted by anything and must therefore be handled with the utmost care. Depending on the region and the possible shortage of water, the importance of water increases even further. Water consumption is not the only factor. In the construction industry, water pollution from auxiliary and operating materials and processes as well as other contaminants and their resulting load on wastewater play an important role. The sources for wastewater on tunneling construction sites are various: Washing water, seepage water accumulating in construction pits, tunnel water, water used in the slurry circuit in fluid-assisted tunneling methods or water from concrete work and stone cutting all these waters are contaminated with a range of pollutants like solids, hydrocarbons, heavy metals, etc. These contaminants can be removed or treated/reduced with the help of specifically designed wastewater treatment plants (WTPs). After the treatment the cleaned water can be either, in best case, reused on the construction site itself or discharged into water utilities like the available sewer or river pin respecting their discharge requirements. Due to dwindling water resources globally, the continuously rising discharge limits and the ever more important aspect of sustainability the use of WTPs on tunneling construction site will be indispensable. In this paper, it will be presented how these systems are designed and work, what advantages they offer environmentally as well as financially and what to look out for when planning and implementing such a system onto jobsite.

Jun 23, 2024

By Giuseppe M. Gaspari, Tamara Kondrachova

Contract practices affect cost and schedule of tunneling works, impacting risk allocation between Owners and Contractors. The Authors compiled a dataset of projects constructed in the Toronto Area between 1990–2020 procured either Design-Build or Design-Bid-Build. Data were analyzed identifying independent cost variables across the two methods. Overall industry efficiency further comparison with historical information demonstrates the costs of engineering ongoing escalation due to rising trends in environmental requirements and public consultations stirred through modern communicative platforms. These hard to predict and estimate costs need to be included in the risks evaluated and managed by Owners and not by Contractors

Jun 13, 2021

By David J. Hatem, K. Bhattarai

The increasing popularity of alternative methods in delivery of underground infrastructure projects has given rise to innovative and collaborative contracting strategies to allocate and manage the unique risks associated with the work. This paper presents approaches and recent examples of how risk has been dealt with using various alternative delivery methods, including Progressive Design Build (PDB) and Construction Manager/General Contractor (CM/GC). Based on the experience gained from these examples, recommendations for an innovative and collaborative risk baselining approach using contingency sharing are presented that should advance the overall goals of equitable risk sharing and compensation.

Jun 13, 2023

Contents

Jan 1, 1985

By Claude Boisjoly, Pierre de Courval, Don Nguyen

The Sainte-Marguerite-3 (SM3) hydro project, presently under construction, requires the excavation of an underground powerhouse and large water conveyance tunnels. This paper describes the planning of the project, main features of underground structures, excavation techniques and ground support.

Jan 1, 1997

By D. D. Potter

ABSTRACT OF ORAL PRESENTATION Extraordinary conditions are often encountered when designing large blasts for in situ mining methods and spatial or innovation techniques are sometimes required. Some of the considerations in designing these large blasts will be discussed with emphasis on those factors that concern powder factor, rock movement and fragmentation. Sources of basic data will be described, along with some of the methods for obtaining these data.

Jan 1, 1977

By Mary C. Jennings, Peter F. Marcus

This paper examines the dynamics of aluminum consumption (all products), scrap recovery and primary aluminum capacity for the Western World through 1995, with particular emphasis on the U.S. aluminum industry. The relationship between the prices of ingot, sheet and extruded products is also explored.

Jan 1, 1986

By Stuart M. Jones, Eugene E. Hively

The Tower Mill is a vertical "stirred" ball/pebble mill recently Introduced In the Western Hemisphere This device offers a significant power savings on wet fine grinding applications when compared to conventional tumbling mills This paper describes the laboratory application of this mill In wet grinding hydrated alumina to products of 50 percent passing 2 to 6 microns

Jan 1, 1983

By Georgy Cherkashov

The geological setting, morphology and physical properties of massive sulfide deposits must be taken into account when designing the underwater systems being currently constructed for mining of this type of marine minerals. Based on more than 20 years experience of hydrothermal mineralization studies in the northern equatorial part of the Mid Atlantic Ridge (MAR) we have provided the following conclusions:

Jan 1, 2008

By B. Suresh, Kalyan K. Das, Pradip

A series of salicylaldoxime derivatives with alkyl group substitution in the main chain and the side chain were synthesized and evaluated for the flotation of malachite, cerussite and smithsonite. The effect of chain length and the position of the substituent group on the selectivity of separation amongst oxidized copper, lead and zinc minerals are discussed in this paper.

Jan 1, 1995

By J. J. Lewis

The chapter describes how several OR techniques assisted the planning of a major new UR project. A computer system was developed to analyze reserves distribution and potential of possible underground layouts, to assist in choosing the location and size of access points. Manpower requirements of each proposed working plan were assessed and matched with the potential recruitment of skilled and unskilled labor. Computer simulations were used to determine the optimum capacity for coal preparation plant and surface bunkerage. For the overall assessment of robustness, financial modelling and risk analysis techniques were adapted to the special requirements of new mines.

Jan 1, 1979

By Vljay K. Chhipa

Artificial intelligence is" an emerging technology in the field of computer application. Expert system have been developed to imitate human intelligence and reasoning process. Expert systems have much scope of application in the decision making process in mineral exploration as such decisions are highly subjective and expert opinions are very helpful. This paper presents a small expert system to analyze reasoning process in exploring for uranium deposits in sandstone.

Jan 1, 1989

By R. C. Freas

Limestone is a basic raw material in the production of cement, lime, a wide variety of industrial products, and a significant percentage of the crushed stone produced in the United States annually. It is used in fluxes, glass making, mineral fillers, environmental applications such as flue gas desulphurization and water treatment, soil conditioners, animal feeds, and as a construction aggregate. This presentation provides an overview of limestone distribution in the United States, it’s production, the variety of products produced, and a brief review of the primary uses for limestone.

Jan 1, 2006