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By D-J Min

Strategies and achievements in the Asian steel industry to construct industrial ecological chain are reviewed largely in the case of Japan, Korea and China. Emphasis is placed on the development of resource circulatory system for the minimisation of various wastes and emissions of green house gases (GHG), toxic gases and polluting particulates. The minimisation includes:Rationalisation of iron and steelmaking processes; Implementation of available relevant measures/technologies; Life cycle assessment in designing steel from semis to assembled products; Reduction, reuse and recycling of materials and energies; and Utilisation of core competence technologies to process domestic and industrial wastes. In view of global nature of the above wastes- and emission-issues, inter-industrial linkage and international cooperation across the borders in the Asian countries have become more important. Inter-industrial linkage definitely serves to cut back the wastes and emissions. Examples of such linkage and factors influencing the sustainability of the linkage are described with expectation for further development of the linkage. Importance of international cooperation cannot be overstressed under the circumstances where steel production in China exceeded 220 Mt and world production exceeded 945 Mt in 2003 and is still increasing. Practical measures are discussed to enhance the linkage and cooperation for effectively promoting the reduction, reuse and recycling, including implications for the nonferrous industry.

Jan 1, 2004

By H. R. Stoger

"In 1994 world trade grew by 9%, the fastest annual increase since 1976. Dry cargo shipping rates are at an all time high.Panamax size bulk carriers are receiving19 000 US dollars per day for trans Atlantic round trip voyages. This is good news for the ship owners but not such good news for the industrial users of ocean shipping.The main emphasis of this paper will be on bulk carriers, the charter market and what industrial companies can do to reduce their costs of ocean transportation which is critical to Canadian exporters. Let us look at the charter market in general.Bulk carriers come in four main sizes:1.The Capesize bulk carriers of 110 000 to160 000 tons that are primarily used to transport iron ore and coal;2.the Panamax bulk carriers of about 70 000tons dwt. This is the largest size (with a beam of 105 ft) that can transit the Panama Canal.3.the Handymax bulk carriers of 40/45 000tons dwt; and4.the Handysize bulk carriers of 20/35 000tons dwt.The handysize vessels are usually craned or geared and carry a variety of bulk cargoes including steel. Ship sizes have increased over the years and the mining industry now uses primarily capesize or Panamax bulk carriers.International chartering is conducted through an international network of shipbrokers. There is usually one broker representing the ship owner and another broker who represents the charterer. The major chartering centers are London and New York but a great deal of chartering activity is conducted in regional markets such as Hongkong, Oslo, Montreal and Hamburg.The Biffex Index or Baltic Freight Index is a good measure of dry bulk freight rates. The Biffex is composed of ten major routes. In May1995, the Biffex was at 2310 points. A year earlier it was at 1354, an increase of about 56%."

Jan 1, 1996

By C. E. Hunt

Since the turn of the century, copper-nickel sulphide ores have been processed at the Sudbury, Ontario operations of INCO Limited, currently the largest integrated mining, milling, smelting and refining complex in the free world. Through the years operational, ecomomic, social and legislative changes have dictated the need for research and development directed at mitigating the impact of existing operations on the surrounding natural environment and also the reclamation of areas affected by earlier mining activities. Approximately one hundred years of mining history and the current annual processing of some 12 million tons of ore presents significant challenges with respect to waste disposal, liquid effluent treatment and land reclamation, particularly in light of rapidly evolving environmental regulations' and controls within the Province of Ontario.

Jan 1, 1992

The risk associated with mining induced seismicity is one of the major threats to the safety and sustainability of deep underground mines. This paper describes techniques that allow site practitioners to efficiently control such risks in mines. The proposed approaches rely on ground support to strategically control seismic risk and re-entry time to tactically control this risk. The strategic approach is based on the detailed understanding of past seismicity to as certain the seismic hazard of individual sources throughout the mine. This approach also relies on assessing the potential damage that these sources can induce on nearby excavations using the excavation vulnerability potential (EVP) and rockburst damage potential (RDP) concepts proposed by Heal et al. (2006). It is then possible to investigate how to reduce the risk of experiencing damaging seismicity in mine drives by locally enhancing the ground support system. The tactical approach relies on a proposed methodology to estimate reliable re-entry times or exclusion periods based on the seismic decay following blasting. Some examples of how these techniques have been applied in Australian mines are given.

Jan 1, 2009

By Alfredo O. Del Campo

Copper concentrate smelting has been the subject of significant improvements during the last three decades. Several new processes are being successfully applied at industrial scale, and probably no new copper smelter will be built with the old-fashioned reverberatory furnace. However, because of financial reasons, the existing reverberatory furnaces, which smelt a significant part of the copper produced worldwide, are likely to last at least another decade. Some improvements have been introduced in reverberatory smelting practice, the best known being the use of oxyfuel burners. However, efforts to optimize the reverberatory furnace operation through automatic control have not been reported. The complex and semi-continuous nature of the process makes it dificult to find a suitable strategy for its automatic control. Many factors, like fuel economy, productivity, boiler capacity, refractory wear, converter slag return, copper losses in discard slag, etc. are interconnected. The chosen control strategy should take into account all these factors to achieve good economic results. A detailed discussion of these problems is presented.

Jan 1, 1984

By C. Kosloski, E. McCullough, A. Fox, S. Reed

This paper serves as a reference guide for creating or strengthening student chapters of the International Society of Explosives Engineers. This includes chapters that are just starting, currently undergoing transition in leadership, or that are in the process of rebuilding. ISEE student chapters have great potential to increase student involvement and national membership, and can benefit from formalized strategies to help them do so. Several key strategies are introduced and should be employed to promote organizational participation throughout the university system.

Jan 1, 2016

The mining industry continues to experience a skills shortage and this is having an impact on the ability of mining companies to operate sustainably. Apart from a few exceptions, there is a dearth of geologists, mining engineers, metallurgists as well as environmental scientists and other professionals in the global mining industry. This relates to both quantity and quality. It makes good business sense for mining companies to employ local professionals rather than expensive expatriate staff. In some cases a mining company could employ more than 10 local mining engineers for the cost of one expatriate. However, in many countries local professionals are not always equipped professionally to work on mine sites. The result is that many companies are not operated optimally due to human resources gaps. In some cases, particularly in key areas such as mine planning, this threatens the sustainability of the operation or at the very least results in sub-optimal resource utilisation. This paper briefly presents some of the issues and strategies being implemented and that might be implemented to maintain a sustainable supply of quality minerals graduates to the industry in 2011 and beyond.

Jan 1, 2011

By ManhKha Trinh, Neal Pyke

Dofasco was the first company to adopt oxygen steelmaking in North America in 1954, two years after the first LD vessel installed and operated successfully in Linz, Austria. Since then, Dofasco has investigated and implemented several strategies to maximize hot metal usage and minimize overall cost. Some key strategies -low hot metal silicon, combined blowing conversion, vacuum degassing tank upgrade and BOF slag carryover control - are discussed. Post combustion, scrap preheat, carbon injection trials along with current operating philosophies are described.

Jan 1, 2004

The resources industry is unique in that the finite nature of resource deposits requires a participant to be constantly locating and developing new ones to replace those that are depleted. An effective growth strategy that enables new project developments to be brought on line in time and within budget is therefore of fundamental importance to any mineral resources company. This paper seeks to identify the role of the development project in the company's overall growth strategy and the key performance criteria that a development project must achieve in order to allow a company to meet its growth objectives.

Jan 1, 1997

By Ruifeng Li, Yanghui Ren, Hua Gao

"Since entering the new century, China’s coal industry has witnessed the rapid development, and provided a reliable energy supply for the national economic and social development. But after the “golden decade” of rapid development, the coal industry now is facing overcapacity, low industrial concentration and production efficiency, high pressure of production safety and environmental protection and other prominent issues. Based on defining the connotation of highly-efficient recovery of coal resources, this paper established the relevant 8 indicators to reflect the highly-efficient recovery level of coal resources, summarized the present situation of China's coal resources recovery and the main problems, analyzed the development environment of China's coal industry under the new situation, and finally put forward the strategic measures to promote highly-efficient recovery of coal resources in China.1. Background Coal is the main energy in China. Since entering the new century, China's coal industry has made significant progress, and the level of production safety, resource recovery rate and mining mechanization increased significantly, which provided a reliable energy supply for the rapid development of the national economy. However, due to the changes of China's economic environment, slow growth of energy demand and other factors, some prominent contradictions in the coal industry have significantly restricted the healthy development of the industry. The first problem is serious overcapacity. In the past few years, 16 industries including coal, electric power, chemical and others have invested in coal mines. It is reported (Han 2016) that only during the nine years from 2005 to 2014, the fixed assets of coal industry increased totally more than 3.3 trillion RMB, which brought a large number of production capacity. Affected by the slowdown of economic growth and energy structure adjustment, Chinese coal demand has reached the peak platform and caused the overcapacity of coal supply, so shutting down the backward capacity is the most important task in the future. The second problem is the low efficiency of coal production. There are about 4.3 million coal mine workers in China, and the annual coal production per capita is less than 900 tons, while it was reported (EIA 2016) that the annual production per capita in the United States is more than 10 thousand tons. The third problem is that the green coal resources are not rich. Among the 1.53 trillion tons proven reserves, only about one third are green coal resources in accordance with the principle of ""safety, technology, environment and economy"". The coal resources with high quality and easily mining conditions are not abundant."

Jan 1, 2017

By -Ing. Alexander Dohmen, -Ing. Gunter Hagen

In order to improve the thermal environment in deep coal mines, two principles can be applied: firstly, the reduction of heat flow into the air stream, and secondly, cooling of the air current. First of all one should try to minimize the heat-flow rate into the air stream underground by the mining method itself. German coal mines prefer the caving system of advance longwall mining simultaneously on several levels with ascensional ventilation. The effects of descensional ventilation and different face ventilation layouts on the thermal environment are discussed, besides the effects of pneumatic and hydraulic stowing. Application of all mentioned possibilities together instead of today's common mining method would reduce the Basis Effective Temperature considerably. In the future, hydraulic haulage of the raw coal underground substituting belt conveying may be a mean to improve the thermal environment further on. If the working depth of a coal mine exceeds about 1 000 m, cooling of the air stream under-ground will be necessary in addition to the above- mentioned measures. Generally, in German coal mines different types of indirect-contact air coolers located nearby the face are used. Besides such so-called cooling coils, large-capacity spray coolers are used because they work more efficiently if a great cooling duty is demanded. Common designs of both air cooler types and their possible utilizations are demonstrated. Deep coal mines in the Federal Republic of Germany need up to 30 MW of total cooling capacity. Mostly, the needed chilled water is cooled by large-capacity refrigeration plants placed on surface, underground or in combination of the above locations nearby the shaft. Due to the increasing underground cooling demand, the distribution of the chilled water and the control of the air coolers become more important. The conception of a control system is discussed, which is based on the control of the single air coolers. All air coolers of a mine are controlled so as to optimize the supply water-flow rate with regard to the demanded cooling duty of the coolers. On the next upper level of the control system the whole chilled water network and finally the refrigeration plant is regulated. Present research work deals with the use of ice for cooling mines. There are some unsolved problems in this new cooling concept. Some aspects of making, transporting and storing ice are described. The use of ice may probably reduce the cooling costs of German collieries, which are at present approximately 4 DM per ton of saleable coal.

Jan 1, 1989

By R. Elliott, C. A. Pickles, J. Peacey

As the nickel sulfide ore deposits become decreasingly viable as a source of nickel metal, increasing attention is being paid to the exploitation of the nickeliferous laterite ores. Attempts to produce a high grade ferronickel concentrate from these ores by pyrometallurgical methods face several challenges, in particular the selective recovery of the highly disseminated nickel from the reduced ore. The current work explores strategies for maximizing the size of ferronickel particles formed in order to improve the selective recovery of the ferronickel by magnetic separation. The effect of various coal, elemental sulphur, pyrite and sodium sulphate additions on ferronickel particle formation and size at 1000°C have been investigated. It has been observed that increased coal additions leads to a moderate improvement in the size of the ferronickel particles, while the presence of any sulphur bearing reagent leads to a significant increase in particle size. The retention of sulphur in the reduced material has also been studied, showing sodium sulphate has the highest retention, followed by pyrite and then elemental sulphur. An inverse trend was observed in the efficiency of sulphur retention on the basis of residual mass of sulphur per unit mass of reagent added.

Jan 1, 2015

By S Coward, C Xu, P A. Dowd

"This paper provides an assessment of the current challenges in strategic mine planning and design and suggested approaches for addressing them. The specific challenges covered are: realistic quantification of downstream processes applied to orebody models to provide an integrated approach to mine design and optimisation modelling, estimation and simulation of geometallurgical variables and their integration into resource and reserve estimation and mine planning modelling, estimation and simulation of new variables for new forms of mining – deep mining, particularly block caving, and solution mining flexibility in planning and design to manage risk and minimise its impact information technology (IT) infrastructure and platforms for rapid online data collection, storage, access and processing.Most of these challenges require new types of data, variables, modelling and estimation methods. Foremost among the new types of variables and data are geometallurgical and dynamic rock mass characterisation variables. New types of data and data collection include rapid generation of very large amounts of online sensor data and the consequent need for rapid processing and modelling of these data.This paper outlines the challenges and strategies in each of these areas and uses examples of models and outputs to illustrate approaches and potential solutions.CITATION:Dowd, P A, Xu, C and Coward, S, 2014. Strategies for mine planning and design, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 41–50 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 24, 2014

By R Trueman

An improved ability to predict dilution for narrow vein deposits enables more accurate economic comparisons between mechanised longhole stoping and other narrow vein mining methods, as well as reducing uncertainty surrounding dilution estimates for deposits at the prefeasibility/ feasibility stage. This paper proposes narrow vein dilution prediction and minimisation strategies for both greenfield sites and operating mines, respectively. The narrow vein dilution method (NVD method) is a tool for more accurately predicting longhole narrow vein dilution. The method is based on a new concept called benchmark stoping width. Benchmark stoping width is based on probabilistic analysis of overbreak distributions from a typical longhole narrow vein mine. The premise for the NVD method is that dilution associated with longhole stoping can be predicted using the benchmark stoping width. In addition to dilution prediction, the NVD method also includes strategies for narrow vein dilution minimisation generally, including; filling, cablebolting, stress relaxation, extraction sequencing and blast overbreak.

Jan 1, 2008

By Mehdi Razavi

Scope of the Study The possibility and risk associated with mining two stopes at the same time The influence of Creighton Fault on the stability and dilution The effect of irregular shape of stope walls on overall stope stability and ore dilution The support requirements for proposed mining plan

Oct 1, 2010

By Wayne Stange

Due to the availability of user-friendly microcomputer based packages, the use of simulation is increasing.. Users have however encountered problems inherent to the structure of sequential-modular simulators. These are the difficulties associated with estimating parameters for arbitrary' models and the solution of design and optimization problems. The implementation of an optimization routine in the simulator MicroSim has facilitated the solution of such problems. The literature indicates that more efficient numerical techniques for solving optimization problems than those presently used in MicroSim are available. These techniques, together with user-interfaces which allow such problems to be specified easily by users, will result in the development of simulators much more powerful than existing ones.

Jan 1, 1989

By David Martin Menne, Chris Campbell-Hicks

Optimisation of many oxide gold processing facilities, in most cases, either does not really take place or if it does take place it happens too late or takes too long. This is unf01tunate as extra profits and early cash flows are lost, in new projects, and/or may not be realised at all in others. The situation is easily avoid­ed by ensuring that the plant optimisation happens immediately following commissioning or for an established operation simply 'biting the bullet' and making it happen immediately as a 'better late than never' decision. This type of optimisation requires intense undiluted focus on each and every problem or restriction that contributes to reduced plant performance or bottlenecks, without letting go, until the predetermined outcome is produced. Thus a dedicated person with specific quantative goals is required for these tasks. Methodology and strategies for optimi­sation are discussed and numerous examples presented. The secret of successful heap leaching is discussed.

Jan 1, 1998

By V. Vekris

A diverse patent portfolio and an effective intellectual property strategy are vital in today’s small business world. Not only does a diverse patent portfolio enable a company to secure a monopoly within the market, it greatly increases the value of a company’s intangible assets and keeps competitors at bay. An overview of the patenting process as it pertains specifically to the materials science-related start-ups will be given, together with a summary of some general patenting strategies and a review of some patenting errors to be avoided, such as premature disclosure of the invention to the public. Additionally, a review of new “green technology” initiatives recently adopted by Patent Offices around the world is also provided. These initiatives are expected to greatly benefit patent applicants in the fields of metallurgy and mining, where research efforts are often directed to environmentally-friendly products and processes. INTRODUCTION Patents are playing an increasingly significant role in the business world. A diverse patent portfolio can enable a company to secure a monopoly within the market, which can provide a competitive advantage over competitors. At the same time, patent portfolio of any size can greatly contribute to the total value of a company’s intangible assets. As an example, Nortel entertained bids in 2011 for its portfolio of about 4000 patents, a large portion of which were directed to 3G- and 4G-mobile communication technologies. The portfolio was eventually sold for $4.5 billion to a consortium including Apple, EMC, Ericsson, Microsoft, Research in Motion, and Sony. Copper mining, and indeed the global mining industry as a whole, is facing challenges. Ore deposits are increasingly low grade, complex, and deeper in the ground, rendering copper mining operations more difficult and costly. Production costs are increasing. According to one study, the cost of producing copper has increased by an average of 10% per year since 2005 (Cantallopts, 2017). To illustrate, the cost of producing a pound of copper in 2005 was 90 cents, but had increased to 217 cents by 2014.

Jan 1, 2019

By J. H. Kempton, D. Atkins

Predictions of delayed environmental impacts from mining—degradation that won’t begin for hundreds of years, but will then continue for thousands—present new permitting challenges. Examples include evaporative concentration in pit lakes, which can eventually cause metals concentrations to exceed human and wildlife toxicity standards, and delayed degradation of groundwater by slow moisture percolation through acid-generating tailings and waste rock. Given the time-value of money, the present worth of such delayed impacts is insignificant, yet they are unacceptable undercurrent laws and cultural values. Long-term financial set-asides offer a possible solution, first funding infrequent, long-term monitoring, followed by more expensive mitigation when the set-aside has matured.

Jan 1, 2000

By Pratima Meshram Abhilash

In this review, availability of germanium in primary and secondary resources and its recovery from these resources are presented. With nearly 40% germanium consumed in fiber optics and scarcity of resources, the global consumption outplays the primary production. Germanium exists as a substituted element in zinc sulfide matrix of lead–zinc sulfides and lignites. Nearly 60% of the germanium supply is met by zinc refining residues, and about 20–30% of germanium is produced from coal and its by-products. Germanium recovery from various resources such as zinc plant residues, coal and coal plant waste, spent optical fibers, and copper flue dust has been examined. Bioleaching was exploited by few researchers to extract germanium from zinc sulfides, sulfide tailings, jarosite, coal fly ash, and flue dust. This review covers the various work carried out by different chemical separation processes, viz., chemical precipitation, solvent extraction (SX), ion exchange (IX), and membrane processes, as well as biological approaches.

Jan 16, 2022