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By Carroll F. Hardy

THE position of the coal industry has been affected by a wide variety of developments in the production and use of energy. The tempo of development and change has been increasing and the end is not in sight. Legislation is currently being proposed for commercial use of atomic power, and the employment of atomic energy in significant quantity will probably occur about the same time as the decline in production of petroleum and natural gas. But these developments are in the future and have little immediate effect on utilization and marketing of coal. While no one should try to suppress or retard the development of a new and economical source of energy, both the coal and private utility industry should be allowed to question how the nuclear power is to be used, who is to use it, and who is going to pay for it. The taxpayers have a monopoly on fissionable material and the knowledge to employ it. Any commercial use must stem from this source. It is not hard to visualize either taxpayer- subsidized private utility atomic power plants on one hand and super TVA's on the other. In view of the gains of gas and oil in the home heating field, it is interesting to compare the 1940 and 1950 census reports on the kind of fuel used for heating in occupied dwelling units. Table I shows that whereas coal provided 77 pct of the fuel for central heating (furnaces and boilers) in 1940, it was down to 45.4 pct in 1950. However, only about 1 ½ million units were lost in this 10-year period.

Jan 3, 1954

By Harrison R. Cooper

Approximately 40 concentrators throughout the world have successfully adopted computer control for flotation circuit operation since 1969. Successful use of flotation control, gaining up to 2% efficiencies, has largely derived from effective employment of on-stream slurry analyzers and integration of key measurement data through digital processors. Requirements for reliable measurement have also led to improved functional reliability in magnetic flow meters, pH, reagent feed, and other key elements. Methods used in computer control of flotation will be reviewed and variations in operating philosophies will be described with reference to the approaches taken to flotation automation.

Jan 1, 1979

By K. V. Konigsmann

"Concentrate dewatering operations have a significant influence on the economics of base metal beneficiation. The expenditures f or energy and labour per tonne of product are high. The relatively low efficiencies of standard techniques present inducements for process modifications. Development efforts at several Noranda concentrators led to process changes which improved productivity, namely, agitated pulp storage in large vessels, process automation and pressure filtration.IntroductionA program was initiated in 1968 with the aim of improving utilization of manpower and equipment in dewatering operations. The following considerations motivated us in this effort: Firstly, filters and dryers had traditionally been operated continuously and in step with grinding and flotation circuits. The demand for labour and equipment operating time was fixed and was not determined by the rate of concentrate production.Secondly, dewatering equipment had usually been designed to handle the concentrate tonnages which were produced when mill feed grades were high; therefore the equipment operated at less than capacity when treating ores of average metal content. The first goal was the separation of the flotation process from concentrate dewatering by development of a practical storage system for concentrate pulps . A second objective was the gradual introduction of dependable automatic controls. The steep increase in energy costs after 1973 added urgency to the search for dewatering processes which were highly energy efficient."

Jan 1, 1984

By R. Marrill

Mining is a complex and intensive industry. Extracting raw material with different shapes, sizes, chemistry from the earth?s crust and transform them into a standardized and high quality final product is a big processing challenge - which involves energy and control on large scales. Not only is the physical work challenging, the mining industry today is facing unprecedented challenges: Decline of mineral grade and reserves, cost escalation for new developments and modernization, regulations, safety, lack of skilled people, and market uncertainty are the new constant. It is clear that process control and management of electrical power will be of increasing importance to the recovery rates the mine will achieve. The objective of this paper is to provide a quick vision about future trends and evolutions in technology related to these fields and their impact on Electrical Safety and Control of the mineral recovery. The paper will cover trends in safety, energy management and efficiency, communications of data, control room evolutions, plant integration, other control technologies, and we will examine how these technologies provide information and the benefits of aligned reporting systems to address current industry challenges. More than just the trends or breakthrough concepts, current technologies are available today that can be applied in the mineral recovery operations now to help overcome anticipated future challenges will be presented later in this document. Finally, a brief discussion to look at some real tools to help make real time changes to the process while maximizing recovery and optimizing cost.

Feb 27, 2013

With the continuing move towards digital signal based control and measurement, it is inevitable that such technology will be increasingly employed on remote sites. The benefits of increased metallurgical performance, of reduced energy and manpower requirements far outweigh the problems associated with high technology in remote locations, provided that the installation is well thought out from both technical and manpower viewpoints. The new accessibility of vast quantities of process data will uncover previously unthought of savings and profit opportunities but brings with it the responsibility to carefully design the data presentation methods. The resulting changes in installed hardware will force changes in the maintenance and engineering workforce and will affect even the stores and purchasing department methods.

Jan 1, 1985

By J. Standen T.

The main purpose of this publication is to present relevant advances in processes and technologies of importance for consideration in the design of new refineries and the modernization of existing refinery facilities. Operation at current densities of between 300 A/m2 and 350 A/m2 is already part of the criteria customarily implemented on recent projects. This is due in part to the development of permanent cathode technology. In recent years, this technology has also been integrated with process control and automatic electrode handling and preparation machines. The combined implementation of these technologies has the advantage of enabling the process to be monitored, thus assuring traceability and allowing greater knowledge of the process to accrue.

Jan 1, 2007

By Joseph G. Wargo

An investigation of trends in exploration expenditures for a selected group of mining companies was undertaken for the interval 1968-1971. These trends were compared with financial factors that are associated with various groups of companies and the implications of these trends are indicated. The sample consists of 21 mining companies, of these, 19 are listed on the New York Stock Exchange and 2 are listed on the American Exchange. Twenty are American, one is Canadian. All are fundamentally "mining companies" in that they derive the bulk of their income from the ex- traction, sale, and at times, fabrication of metals from their own mines. This is in contrast to companies which have mineral exploration departments but derive the bulk of their revenues from sources other than mining, such as oil and gas sales. No companies which can be considered strictly as exploration companies are included in the sample. This definition held up in 1968, however, its strict application became more difficult through the years. In 1971, three or four of the companies were changing their character in that they were phasing out of the mining business and deriving a substantial part of their income from activities other than mining.

Jan 5, 1973

By R. Stenne

This paper presents the trends in deep foundations in Europe, both in terms of design and construction. Eurocode 7 which is a design code for geotechnical engineering will be introduced in the European Union member countries, and will oblige geotechnical engineers to abandon traditional methods based on a global factor and adopt a new approach based on partial factors of safety. Execution codes (for construction of foundations and other geotechnical processes) are currently being introduced without problems. Ever more demanding environmental constraints push foundation contractors to adapt old techniques and develop new ones to comply with new regulations.

Jan 1, 2000

By Anthony T. Jones

Deep seabed mining requires technology to collect materials and transport them to the surface. An international patent search was conducted to define the state of the art in seabed mining technology. Over 350 patents were identified from 12 patent systems. The majority was from the United States, Japan, and the former USSR. Patent activity in this field peaked in 1983 when 34 patents were issued. Since 1984, on average 6 patents have been issued annually. The technology represents ten major classifications. With the exception of Deepsea Ventures, Kawasaki and International Nickel, it appears that much of the technology developed and tested in the 1970s by consortia active in seabed mining was never patented. Over the past two decades, identifiable trends in marine technology could influence seabed mining application such as more sophisticated communication systems, advances in hydraulic manipulators, improved computational technology in navigation, modeling of vessel ? ocean interactions, and improved materials. The most significant recent activity has been in European applications, which disclose remotely controlled subsea vehicles for mining diamonds.

Jan 1, 2001

By V. M. Paretsky

Recent developments made in the Gintsvetmet Institute in the field of autogenous smelting processes have confirmed that autogenous smelting continues to be the main prospective technology for pyrometallurgical processing of sulfide raw materials. This technology ensures energy conservation and environmental safety conforming to the current world standards for production of heavy non-ferrous metals. Two alternative processes of single-stage autogenous smelting producing white metal as well as high-basic ferrite-calcium slags have been developed and can be recommended for technical modernization of Russian copper smelters.

Jan 1, 2002

By A. Santha Ram

The Indian Mining sector is subjected to a number of trends including call for global transition towards the route to sustainable development. Several regulations were enacted by the Government departments, from time to time, in order to identify the problems faced by the mining industry, including small-scale mining operations and to suggest appropriate mitigation measures in the form of environmental standards and certifications. During this process, a pursuit of sustainable development is regarded as an important area responding to socio-economic conditions, priorities and thus guides eventually corporate policies and practices. Thus, there is a need to formulate strategies for sustainable development. Based on these strategies some environmental indicators were developed in order to track down the progress and to evaluate its success. A case study pertaining to a group of iron ore mines in North Goa and Chromite mines in Sukinda, Orissa was selected for this study. Base line environmental data has been generated in the respective study sites. A core set of environmental indicators monitoring environmental progress based on the P-S-R model pioneered by OECD is linked with indicators for assessing the integration of environmental concerns.

Jan 1, 2003

Financial markets are subject to constant change and project finance, as a product within these markets, adapts and will continue to adapt with those changes. A meaningful discussion of these adaptations requires an understanding of differences between non-, limited and full recourse project finance. The reasons sponsors seek and lenders provide project finance are also pertinent in this context. Arranging a project, financing package can be a canplex and time consuming task. An important first step is choosing the right advisor for the assignment and then structuring and tailoring the financing before approaching prospective lenders. The last thirty years has seen changes in the needs of sponsors and the ability of lenders to meet them. These shifts in preference may well be a guide to the future. Several major project financings successfully canpleted in Australia in the last few years and more recent examples are broadly discussed. Project finance will be keenly sought in the future and the form and nature it takes will continue to vary.

Jan 1, 1983

By Alan Bauer

New developments in drilling, blasting and explosives in both open-pit and underground mining operations are discussed, as well as novel surface blasting techniques such as are used in tar sand mining.

Jan 1, 1978

By Alan Bauer

During the past several years, the trend to large-diameter blastholes in both open pits and underground mines along with the continuing developments in slurried explosives and delay systems has kept things exciting for the drilling and blasting engineer. This has been particularly so in underground mining, where new mining systems having lower cost and higher productivity have emerged. Crater technology has produced new large-scale methods for resisting front penetration in tar sand mining and also new underground retreat mining methods and methods of raising.

Jan 1, 1978

Earnings of engineers in the period 1956 to 1958 continued the upward trend observed in the previous survey interval, 1953 to 1956. The overall median (all graduates) was $6500 in 1953, $7750 in 1956 (a 19 pct upstep or about 6.5 pct annually), and $8750 in 1958 (up 13 pct from 1956 or 6.5 pct average yearly). The latter represents an increase from mid-1956 to mid-1958. For this same two-year span the Consumer Price Index rose 1.5 pct and the Average Gross Weekly Earnings for Production (Manufacturing) climbed close to 10 pct. Median earnings for the major classifications studied are presented in Table I. The increase in engineering earnings are not distributed equally among the various activity classifications or among the experience levels of the survey. Summary results of the changes of the median lines for the major divisions are presented in Table 11. Data in this table are approximations- dollars are rounded to the nearest $50 unit and percentages to the nearest full percentage.

Jan 1, 1959

By James C. Cawley

This paper updates an earlier report by the authors that studied electrical injuries from 1992 to 1998. The previous information is expanded and supplemented with fatal and nonfatal injury rates and trends through 2002. Injury numbers and rates were used to compare and trend electrical injury experience for various groups and categories. This information allowed identification of at-risk groups that could most benefit from effective electrical safety interventions. The data presented in this paper are derived from the U.S. Labor Department?s Bureau of Labor Statistics? Census of Fatal Occupational Injuries, Survey of Occupational Illnesses and Injuries, and Current Population Survey. Between 1992 and 2002, 3378 workers died from on-the-job electrical injuries. Electricity remained the sixth leading cause of injury-related occupational death. From 1999 to 2002, 4.7% of all occupational deaths were caused by electricity, down from 5.2% in the 1992?1998 time period. The cause of death was listed as electrocution in 99.1% of fatal cases. Contact with overhead power lines was involved in 42% of all on-the-job electrical deaths. The construction industry accounted for 47% of all electrical deaths between 1992 and 2002 but showed overall improvement from 1995 to 2002 by reducing its electrical fatality rate from 2.2 to 1.5 per 100 000 workers. In addition, 46 598 workers were nonfatally injured by electricity. Contact with electric current of machine, tool, appliance, or light fixture and contact with wiring, transformers, or other electrical components accounted for 36% and 34% of nonfatal electrical injuries, respectively. Contact with underground buried power lines was involved with 1% of fatal injuries and 2% of nonfatal injuries. The research of the National Institute for Occupational Safety and Health aimed at evaluating commercially available overhead power line proximity warning alarms is described. This paper is expected to be the initial step for eventual development of a performance standard for such systems.

Jan 1, 2008

By Gerald T. Homce, James C. Cawley

This paper updates an earlier report by the authors that studied electrical injuries from 1992 to 1998. The previous information is expanded and supplemented with fatal and nonfatal injury rates and trends through 2002. Injury numbers and rates were used to compare and trend electrical injury experience for various groups and categories. This information allowed identification of at-risk groups that could most benefit from effective electrical safety interventions. The data presented in this paper are derived from the U.S. Labor Department’s Bureau of Labor Statistics’ Census of Fatal Occupational Injuries (CFOI), Survey of Occupational Illnesses and Injuries (SOII) and Current Population Survey (CPS). Between 1992 and 2002, 3,378 workers died from on-the-job electrical injuries. Electricity remained the sixth leading cause of injury-related occupational death. From 1999 through 2002, 4.7% of all occupational deaths were caused by electricity, down from 5.2% in the 1992 to 1998 time period. The cause of death was listed as electrocution in 99.1% of fatal cases. Contact with overhead power lines was involved in 42% of all on-the-job electrical deaths. The construction industry accounted for 47% of all electrical deaths between 1992 and 2002, but showed overall improvement from 1995 through 2002 by reducing its electrical fatality rate from 2.2 to 1.5 per 100,000 workers. An additional 46,598 workers were nonfatally injured by electricity. Contact with electric current of machine, tool, appliance, or light fixture and contact with wiring, transformers, or other electrical components accounted for 36% and 34% of nonfatal electrical injuries, respectively. Contact with underground, buried power lines was involved with 1% of fatal injuries and 2% of nonfatal injuries. NIOSH research aimed at evaluating commercially available overhead power line proximity warning alarms is described. This research is expected to be the initial step for eventual development of a performance standard for such systems.

In discussing the Asia-Pacific region weare talking about a region which has more than 60% of the world's population, a regional economy which will in 10 years be larger than the European Economic Community, and a group of countries with some of the highest electricity generation growth rates in the world. It is economically the most dynamic region in the world.

Jan 1, 1990

By A. C. Lordi

Present industrial plant design is influenced by motivators beyond the usual powerful one, creativity, on which Consultants thrive. The respected, although annoying, ever-present Return on Invested Capital becomes even more significant with anticipated escalation. Government regulations are having an increasing influence as air and water protection, sound and electrical safety requirements must be met And more recently, the increasing cost and uncertain availability of energy sources are having a revolutionary affect on plant design. More than ever before, the Consulting Engineer is faced with requirements and restrictions which tax even the most original thinkers -- and the result is good. This paper includes a brief review of recent trends in Cement Plant Engineering Design.

Jan 1, 1975

By Arthur Grounds

Historical In the course of a paper which is necessarily limited in length, such as the present one, it is obviously impossible to describe in detail the history, development, and present position of coal preparation in Western Europe. Great Britain has been blessed with large deposits of excellent coal of nearly every type, ranging from the high-grade anthracites of South Wales, which are characterised by their very low ash and volatile con-tents, to the superb coking coals of South Wales and Durham -probably the finest in the world -with their low ash and sulphur contents, the latter constituent often well be-low l per cent. Gas coals abound in Lancashire and Yorkshire, while coals from the East Midlands, Northumberland, and Scotland are excellent for steam-raising and other industrial purposes. The excellent quality of these various coals has, in years gone by, ensured ready .sales abroad and it is not surprising, therefore; that methods of coal preparation were largely developed on the Continent in an endeavour to upgrade the inferior fuels found there, so that the prepared product could compete with British coals on the European market.

Jan 1, 1951